Resolution of thoracic limb lameness associated with traumatic suprascapular neuropathy in a dog: case report

Resolution of thoracic limb lameness associated with traumatic suprascapular neuropathy in a dog: case report | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Resolution of thoracic limb lameness associated with traumatic suprascapular neuropathy in a dog: case report Afroditi Evangelia Pontikaki, Stephanie Mella, Gemma Walmsley, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8916595/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background: Traumatic suprascapular nerve injury is well recognized in both horses and humans, however, the condition has not been reported in dogs. The suprascapular nerve innervates the infraspinatus and supraspinatus muscles, and trauma of the nerve can result in profound atrophy of these muscles and mechanical lameness. Case presentation: A 4-year-old male neutered Cocker Spaniel was presented with moderate lameness of the left thoracic limb and severe muscle atrophy of the supraspinatus/infraspinatus muscles. Gait alterations included abduction of the elbow joint during the weight bearing phase, resembling those observed in dogs with infraspinatus contracture. Magnetic resonance imaging of the caudal cervical spine and left thoracic limb revealed segmental enlargement of the left suprascapular nerve at the level of the cranial endplate of C7 and marked diffuse homogenous signal changes and atrophy of the left supraspinatus and infraspinatus muscles. Electromyography revealed moderate to severe spontaneous activity isolated to the supraspinatus and infraspinatus muscles consistent with denervation. The patient was presumptively diagnosed with traumatic suprascapular nerve injury and, following a period of exercise restriction, exhibited a marked improvement in clinical signs. The owner reported a return to normal gait and exercise at 9 months follow-up. Conclusion: To the authors’ knowledge, this is the first case report to describe the presentation, investigations and management of suprascapular nerve injury in a dog. Traumatic injury of the suprascapular nerve, although rare, should be considered in dogs presented with unilateral thoracic limb lameness. Accurate diagnosis and appropriate management of the condition could lead to favourable outcome. Figures Figure 1 Figure 2 Figure 3 Figure 4 Background The suprascapular nerve (n. suprascapularis, SSN) supplies motor (general somatic efferent) innervation to the supraspinatus and infraspinatus muscles who provide stabilization of the lateral aspect of the shoulder ( 1 ). The nerve typically originates from the sixth and seventh cervical spinal nerves (C6 and C7) with contribution from the fifth cervical nerve (C5) ( 2 – 4 ). After exiting the cranial brachial plexus, the SSN enters the distal intermuscular space between the supraspinatus and subscapularis muscles medially, and travels towards and then curves laterally around the cranial margin of the scapular neck. The nerve is therefore vulnerable to trauma at this level where it runs in close proximity to bone ( 3 – 5 ). In 1943, Seddon described a classification system for nerve injuries based on the degree of damage to the axons and supporting connective tissues ( 6 ). The mildest form, neuropraxia, is a transient block of nerve conduction without loss of axon continuity; often occurring due to stretch or crush injury, demyelination and the resulting loss of sensory and motor function are fully reversible within days to weeks. Axonotmesis describes disruption of the axons; however, as the epineurium and perineurium remain intact, regrowth is possible but recovery is more prolonged (over months to years) and return to function less certain ( 6 , 7 ). The most severe form of nerve trauma is neurotmesis which involves complete transection of the nerve and surgical intervention is necessary to restore nerve function ( 6 – 8 ). In veterinary medicine, traumatic SSN injury has been described most commonly in horses where it is also known as Sweeney ( 9 ). The condition results in supraspinatus and infraspinatus muscle atrophy, accompanied by signs of pain, and varying degrees of thoracic limb gait abnormality caused by lateral shoulder joint instability. Resolution of the condition is determined by the severity of the nerve trauma ( 9 ). In dogs, contracture of the infraspinatus muscle has been described in active medium to large size dogs ( 10 ). Dogs are presented with acute thoracic limb lameness following vigorous activity. The exact aetiology of the condition remains unknown; however, data obtained from electrodiagnostic, and histopathological findings suggest a primary muscle disease ( 5 , 10 , 11 ). To the authors’ knowledge, traumatic injury of the SSN has not previously been reported in dogs. This case highlights a rare but essential differential diagnosis for unilateral thoracic limb lameness in dogs. Clinical suspicion of traumatic SSN injury should be raised in dogs with history of trauma in cases presented with unilateral thoracic limb lameness and associated muscle atrophy. Advanced imaging and electrodiagnostic studies play a key role to localise the lesion and support the diagnosis, while conservative management could lead to full recovery. This case report demonstrates the clinical presentation of SSN injury in a dog and offers valuable insights into the diagnostic approach, management and prognosis of such cases. Case presentation A 4-year-old male neutered Cocker Spaniel was presented to the Orthopaedic Service at a Referral Hospital for further investigation of chronic left thoracic limb lameness. The signs started acutely four weeks prior to presentation as a non-weight bearing lameness following a traumatic event - his left thoracic limb became trapped in a tree whilst exercising off lead. There had been no history of lameness or gait abnormality prior to this incident. Diagnostic investigations performed by the primary veterinarian revealed normal complete blood count and serum biochemistry [Table 1 , 2 ]. Radiographs of the shoulder joints, computed tomography of the thoracic limbs and cervical spine, and arthrocentesis of the left shoulder joint was also performed prior to referral and revealed no abnormalities aside from severe atrophy of the left supraspinatus and infraspinatus muscles. A course of pain relief [robenacoxib 2mg/kg per os (PO) every 24 hours, paracetamol 400mg /codeine 9mg (20mg/kg and 0.45mg/kg respectively) 23mg PO every 8 hours] was prescribed, no improvement of the lameness was reported. Table 1 Test Result Unit Reference Interval GLU 5.92 mmol/L 4.11–7.95 CREA 89 µmol/L 44–159 UREA 6.9 mmol/l 2.5–9.6 BUN/CREA 19 - - PHOS 1.03 mmol/L 0.81–2.20 CA 2.55 mmol/L 1.98–3.00 TP 65 g/L 52–82 ALB 31 g/L 23–40 GLOB 34 g/L 25–45 ALB/GLOB 0.9 - - ALT 18 U/L 10–125 ALKP 51 U/L 23–212 GGT 4 U/L 0–11 TBIL < 2 µmol/L 0–15 CHOL 3.94 mmol/L 2.84–8.26 AMYL 683 U/L 500–1500 LIPA 685 U/L 200–1800 cPL Normal Serum Biochemistry – Catalyst Dx Table 2 Test Result Unit Reference Interval RBC 8.52 x10^12/L 5.83–9.01 HCT 52.8 % 36.6–54.5 HGB 16.5 g/dL 12.2–18.4 MCV 61.9 fL 55.8–71.6 MCH 19.4 Pg 17.8–28.8 MCHC 31.3 g/dL 30.9–38.6 RDW 15.3 % 14.7–17.9 %RETIC 0.5 % - RETIC 46.4 K/µL 10.0–110.0 WBC 6.81 x10^9/L 5.50–16.90 %NEU 65.2 % - %LYM 19.9 % - %MONO 11.6 % - %EOS 2.8 % - %BASO 0.5 % - NEU 4.45 x10^9/L 2.00–12.00 LYM 1.35 x10^9/L 0.50–4.90 MONO 0/79 x10^9/L 0.30–2.00 EOS 0/19 x10^9/L 0.10–1.49 BASO 0.04 x10^9/L 0.00–0.10 PLT 283 K/µL 175–500 MPV 13.6 fL - PDW 17.1 % - PCT 0.39 % - Complete Blood Count (CBC) – LaserCyte On presentation, the dog was bright, alert, with an ideal body condition (body weight 17.4kg BCS 5/9). Subjective gait analysis found moderate lameness localised to the left thoracic limb, grade 3/10 ( 12 ). The observed gait pattern reflected circumduction of the limb during protraction, with abduction of the elbow joint during the weight-bearing phase, similar to alterations seen in dogs with infraspinatus contracture. Upon physical examination, severe muscle atrophy of the left infraspinatus and supraspinatus with complete prominence of the scapula spine was apparent. The triceps, biceps brachii, and brachialis were also mildly atrophied. There was no hyperaesthesia and the left shoulder joint had normal full range of motion with no instability noted. No pain was elicited on deep palpation of the left axilla, and there was no palpable axillary mass. The right thoracic limb was normal. Postural responses were normal, and cutaneous trunci, perineal and withdrawal reflexes were intact. No abnormalities were detected on cranial nerve examination, and there was no pain evident on spinal palpation. At this stage, the main differentials were traumatic, neoplastic or inflammatory lesions (including migrating foreign body neuritis, although it was considered less likely) localized to the left SSN or C5-C7 nerve roots. Magnetic resonance imaging (MRI) of the caudal cervical and cranial thoracic region was performed using a 1.5 T scanner (Philips Ingenia CX, Philips Healthcare, Best, Netherlands) obtaining T1 weighted, T2 weighted, fat supressed and gradient echo sequences. Gadobutrol (Gadovist) at a dose of 0.1mmol/kg was administered intravenously as a contrast medium. Magnetic resonance imaging revealed focal enlargement of the deep portion of the left SSN at the level of the cranial endplate of C7. The thickened nerve had a moderately heterogenous, but predominantly hyperintense T2W signal intensity, with heterogenous contrast enhancement (Figs. 1 – 3 ). The associated left supraspinatus and infraspinatus muscles were markedly reduced in volume with a diffuse, homogenous T2W-hyperintense signal. The right forelimb muscles were unaffected with normal signal intensity and muscle volume. The remainder of the MRI was unremarkable with the exception of multiple, non-compressive, cervicothoracic degenerative, intervertebral disc protrusions. Following the MRI, electromyography (EMG) of the left thoracic limb was performed under general anaesthesia. Localised, abnormal spontaneous electrical activity consisting of positive sharp waves and fibrillation potentials was recorded in the infraspinatus and supraspinatus muscles only (graded as + + in the infraspinatus and +++ in the supraspinatus; range 0 - ++++ based on Kimura 2001) (Fig. 4 ). This allowed us to exclude disuse as a cause for the atrophy and was most consistent with chronic denervation of the muscles innervated by the SSN. Other muscles evaluated were all normal (electrically silent) including the left biceps, triceps and subscapularis muscles which are innervated by the musculocutaneous, radial and subscapularis nerves respectively. Given the history and diagnostic findings, our presumptive diagnosis was neurogenic atrophy of the infraspinatus and supraspinatus muscles caused by a traumatic neuropathy of the left SSN. A peripheral nerve sheath tumour was also given as a differential, and we discussed with the owners that if clinical signs progressed repeat imaging would be warranted. Conservative management was recommended with rest and controlled increase exercise for the following 12 weeks. At this stage the patient was not considered clinically painful therefore analgesia was not indicated. Follow-up assessment was carried out after 12 weeks, when the dog exhibited a marked improvement in clinical signs. Orthopaedic examination was normal with no lameness at a walk or trot. Substantial palpable improvement of the muscle volume of infraspinatus and supraspinatus was documented, although moderate atrophy remained. No abnormalities were reported upon orthopaedic and neurological assessments. A repeat MRI to further assess the previous lesion in the SSN was recommended but declined by the owner given the dog’s clinical improvement. At the last telephone communication with the owner 9 months after injury, they reported that the dog’s lameness remained in complete remission, he had returned to normal activity and they had no other concerns. Discussions and Conclusions: To the authors’ knowledge, this is the first case report of a traumatic SSN injury causing supraspinatus/infraspinatus muscle atrophy in a dog. Several studies have documented nerve injuries affecting the thoracic limb in small animals, with brachial plexus injury resulting from road traffic accidents most common ( 13 – 15 ). The thoracic limb of small animals is mobile against the body wall and it has been suggested that the nerve roots are susceptible to traumatic avulsion at this level as they are relatively vulnerable to stretching forces ( 16 ). Specific injuries to the SSN are most frequently reported in horses, particularly in draft breeds, and are often attributed to repeated trauma from ill-fitting harnesses ( 9 ). The location of the nerve near the cranial border of the scapula predisposes it to direct compression injuries ( 9 ). In horses, SSN injury is typically diagnosed presumptively based on the key clinical findings of supraspinatus and infraspinatus atrophy; however, the clinical suspicion of SSN injury can be supported ultrasonography and EMG ( 9 ). In the case presented here, the neuroanatomical localization, MRI findings and EMG were all consistent with a lesion of the SSN. The acute onset history associated with trauma and diagnostic findings lead to a presumptive diagnosis of traumatic SSN injury which is strongly supported by the subsequent clinical resolution. Although both CT and MRI are useful imaging modalities for assessment of neuromuscular and musculoskeletal structures, MRI is by far the more superior modality for assessment of specific soft tissue structures. In particular, allows more accurate and detailed differentiation of soft tissue structures, such as nerves, from the adjacent soft tissue structures and vasculature ( 17 ). Various studies in both veterinary and human medicine have demonstrated the enhanced diagnostic quality of MRI images compared with CT for peripheral nerve pathology ( 17 – 22 ). In the context of imaging of the brachial plexus, CT is limited by its restriction to axial plain acquisition, and by artifacts associated with the adjacent tissues of the shoulder ( 17 – 22 ). In this case, CT imaging alone was inconclusive whereas a focal lesion within the left SSN was visible on the MRI study. Our findings are consistent with those described in dogs affected by inflammatory and traumatic lesion of the brachial plexus ( 23 , 24 ). Increased T2W hyperintensity has been associated with several peripheral neuropathies including degenerative, traumatic and neoplastic conditions in both humans and dogs ( 25 , 26 ).Nonetheless, increased nerve T2W hyperintensity remains a nonspecific finding. Interestingly, peripheral neuropathies demonstrate varying degrees of enhancement in both species and in some cases no enhancement is observed. These studies highlight that while MRI findings can be supportive of a neuropathy/nerve injury, changes in signal intensity such as T1W hyperintensity or contrast enhancement are not specific for the underlying cause ( 25 , 26 ). Another study shown that normal sciatic and femoral nerves in dogs do not show contrast enhancement on MRI ( 27 ). Thus, it has been suggested to use fat-suppression sequences in post-contrast T1W images when visualizing diseased nerves, as this allows differentiation of affected nerves from the surrounding fat based on their contrast enhancement ( 27 ). In the presented case, the SSN exhibited both T2W hyperintensity and contrast enhancement and therefore suggestive of a peripheral neuropathy. Muscle atrophy due to denervation is rapid and severe ( 28 ), electromyography found spontaneous activity in the supraspinatus and infraspinatus muscles which is also consistent with denervation due to a SSN lesion. Fibrillation potentials and positive sharp waves as seen in this case are non-specific findings and can also be seen in myopathies ( 8 , 28 – 32 ); however, our clinical examination and radiological findings make this less likely. Fibrillations and positive sharp waves associated with denervation arise due to hypersensitivity of myofibres secondary to sarcolemmal destabilization and develop typically 7–10 days following the injury ( 8 , 31 ). In the acute and subacute phase, reduced or absent voluntary motor unit action potentials (MUAPs) may be detected on EMG, as a result of loss of functional motor units ( 31 ). In contrast, during recovery, MUAPS become polyphasic, with prolonged-duration, and increased-amplitude. As hallmarks of re-innervation and collateral sprouting from surviving axons. In the line with this, spontaneous activity typically decreases ( 31 ). Conscious EMG was not performed in our case however the presence of marked spontaneous activity suggests denervation of these muscles at the time of the examination. The other muscles of the left thoracic limb were normal on EMG indicating that the milder atrophy noted throughout the limb was due to disuse. Peripheral nerve sheath tumor (PNST) was one possible differential diagnosis. Dogs with PNST are commonly presented with similar signs: lameness and muscle atrophy associated with the anatomic location of the lesion and the chronicity of the disease ( 33 , 34 ). The brachial plexus and the lumbosacral plexus are the most frequently affected regions ( 33 , 34 ). PNST in dogs have a guarded to poor prognosis, although outcomes can significantly improve following complete surgical excision or volumetric modulated arc radiation therapy ( 35 ). In a recent study investigating dogs with presumptive and confirmed PNSTs, regardless of treatment, median survival time was 4 months (range 2 weeks to 2 years, 8 months) ( 36 ). The study included different types of nerve sheath tumors (NSTs): cranial NSTs, NST with spinal canal invasion, and NSTs external to the spinal canal. Consistently, all dogs showed progressive clinical signs and were eventually euthanized ( 36 ). Although disease progression and imaging findings alone can be highly suggestive of neoplasia, a definitive diagnosis of PNST requires histopathological evaluation ( 36 , 37 ). In the current case, due to the invasive nature of the procedure and potential morbidity associated with fascicular nerve biopsy, histopathological evaluation was not considered clinically indicated following initial investigations. Instead, a follow-up MRI to monitor disease progression was recommended. Due to the patient’s return to normal mobility, this was declined by the owner. Nevertheless, given the dog’s resolution of lameness and the restoration of the muscle volume at 9 months, these findings would support a focal nerve lesion, secondary to trauma, not consistent with a PNST. To conclude, this case reports the cause of thoracic limb lameness with severe isolated muscle atrophy following a traumatic injury to the SSN which responded to conservative management. Trauma of the SSN, although rare, should be included in the differential diagnosis of the dogs with unilateral thoracic limb lameness with severe infraspinatus and supraspinatus atrophy. Abbreviations CT Computed tomography PO Per os SSN Suprascapular nerve MRI Magnetic resonance imaging EMG electromyography PNST Peripheral nerve sheath tumor NSTs Nerve sheath tumors Declarations Acknowledgements: Not applicable. Authors’ contributions: A. E. Pontikaki: conceptualisation, investigation, writing – original draft, writing – review & editing. S. Mella: investigation, writing – original draft, writing – review & editing. G. Walmsley: investigation, writing – review & editing. R. T. Bentley: conceptualisation, investigation, writing – review & editing. T. Cox: conceptualisation, investigation, supervision, writing – review & editing. Funding: Medivet Ltd. Data availability : No datasets were generated or analysed during the current study. 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Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 12 Mar, 2026 Editor assigned by journal 12 Mar, 2026 Editor invited by journal 25 Feb, 2026 Submission checks completed at journal 24 Feb, 2026 First submitted to journal 24 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8916595","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":606607712,"identity":"595fdad4-5f84-4da4-9567-d564a4da9a6a","order_by":0,"name":"Afroditi Evangelia Pontikaki","email":"data:image/png;base64,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","orcid":"","institution":"Hamilton Specialist Referrals","correspondingAuthor":true,"prefix":"","firstName":"Afroditi","middleName":"Evangelia","lastName":"Pontikaki","suffix":""},{"id":606607713,"identity":"60ffa79b-9a26-481c-a30e-5a9a3f1c7a1a","order_by":1,"name":"Stephanie Mella","email":"","orcid":"","institution":"ChesterGates Veterinary Specialists","correspondingAuthor":false,"prefix":"","firstName":"Stephanie","middleName":"","lastName":"Mella","suffix":""},{"id":606607714,"identity":"d3a98193-8daa-4d1b-96d4-ede54e832ac7","order_by":2,"name":"Gemma Walmsley","email":"","orcid":"","institution":"University of Liverpool","correspondingAuthor":false,"prefix":"","firstName":"Gemma","middleName":"","lastName":"Walmsley","suffix":""},{"id":606607715,"identity":"11ddfcca-1e4e-40d7-9477-12cba1fa0c86","order_by":3,"name":"R. Timothy Bentley","email":"","orcid":"","institution":"University of Liverpool","correspondingAuthor":false,"prefix":"","firstName":"R.","middleName":"Timothy","lastName":"Bentley","suffix":""},{"id":606607716,"identity":"4db7b6fe-4e5b-42a4-a950-d3d66bed0714","order_by":4,"name":"Thomas Cox","email":"","orcid":"","institution":"Medivet Dogwood Referrals","correspondingAuthor":false,"prefix":"","firstName":"Thomas","middleName":"","lastName":"Cox","suffix":""}],"badges":[],"createdAt":"2026-02-19 10:39:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8916595/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8916595/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104874392,"identity":"e1094b61-1b68-4a63-bc20-42c904f14998","added_by":"auto","created_at":"2026-03-18 08:31:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1319505,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTransverse T2W Gradient echo sequence post-contrast. \u003c/strong\u003eThe left suprascapular nerve is focally thickened with a heterogenous T2W signal intensity and contrast enhancement (yellow arrow heads). Distally the left suprascapular nerve tapers to a normal diameter (solid black arrow), similar in appearance to the unaffected right scapular nerve (open white arrow).\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-8916595/v1/05f0261722c4a46cf7fe8bdc.png"},{"id":104874395,"identity":"4a555c31-185a-47a1-b0bd-396a1127330d","added_by":"auto","created_at":"2026-03-18 08:31:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1967134,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTransverse images of the left suprascapular nerve on T2W images (A), T1W images (B) and T1W post-contrast images (C). \u003c/strong\u003eThe focally thickened left suprascapular nerve has a heterogenous T2W signal intensity, hypointense T1W signal intensity and moderate homogenous post-contrast enhancement (black arrow A, B and C). The right suprascapular nerve is normal in thickness and signal intensity across all sequences (open arrow A, B and C). The included portion of the left supraspinatus muscle (asterisk) is reduced in volume compared to the right, with an increased T2W and T1W hyperintensity suggestive of fat infiltration and neurogenic atrophy.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-8916595/v1/b6c6cf718fd0f16cc79fe9a6.png"},{"id":105034236,"identity":"486e510b-59d2-4e78-a8a6-49a4db854cba","added_by":"auto","created_at":"2026-03-20 07:22:55","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2213035,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDorsal T2W and T2W mDIXON (fat suppressed) images of the thoracic limbs\u003c/strong\u003e. The left supraspinatus and infraspinatus muscles are markedly reduced in volume compared to the right and have an increased T2W signal intensity (asterisk).\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-8916595/v1/e3b1e971c85844468cf3d86b.png"},{"id":105034111,"identity":"76313913-8ad3-4e65-9fa8-f46ed72c33bd","added_by":"auto","created_at":"2026-03-20 07:22:40","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":9882,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eElectromyography (EMG) of the left supraspinatus (A), infraspinatus (B) and subscapularis (C) muscles. \u003c/strong\u003eElectromyography revealed fibrillation potentials (A) and positive sharp waves (B) in the left supraspinatus and infraspinatus muscles graded +++ and ++ respectively (scale 0 – ++++) consistent with denervation. EMG of other muscles including the left triceps, biceps and the same muscles on the right was normal (not shown).\u003c/p\u003e","description":"","filename":"figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-8916595/v1/07f1c4629833d3664d93e6a4.png"},{"id":105036525,"identity":"dd152a81-44d0-42c3-8bfa-a9197af03881","added_by":"auto","created_at":"2026-03-20 07:33:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6904086,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8916595/v1/005f2ea3-e92d-4ff5-9b83-c2522b4d6bce.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Resolution of thoracic limb lameness associated with traumatic suprascapular neuropathy in a dog: case report","fulltext":[{"header":"Background","content":"\u003cp\u003eThe suprascapular nerve (n. suprascapularis, SSN) supplies motor (general somatic efferent) innervation to the supraspinatus and infraspinatus muscles who provide stabilization of the lateral aspect of the shoulder (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). The nerve typically originates from the sixth and seventh cervical spinal nerves (C6 and C7) with contribution from the fifth cervical nerve (C5) (\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). After exiting the cranial brachial plexus, the SSN enters the distal intermuscular space between the supraspinatus and subscapularis muscles medially, and travels towards and then curves laterally around the cranial margin of the scapular neck. The nerve is therefore vulnerable to trauma at this level where it runs in close proximity to bone (\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn 1943, Seddon described a classification system for nerve injuries based on the degree of damage to the axons and supporting connective tissues (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). The mildest form, neuropraxia, is a transient block of nerve conduction without loss of axon continuity; often occurring due to stretch or crush injury, demyelination and the resulting loss of sensory and motor function are fully reversible within days to weeks. Axonotmesis describes disruption of the axons; however, as the epineurium and perineurium remain intact, regrowth is possible but recovery is more prolonged (over months to years) and return to function less certain (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). The most severe form of nerve trauma is neurotmesis which involves complete transection of the nerve and surgical intervention is necessary to restore nerve function (\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn veterinary medicine, traumatic SSN injury has been described most commonly in horses where it is also known as Sweeney (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). The condition results in supraspinatus and infraspinatus muscle atrophy, accompanied by signs of pain, and varying degrees of thoracic limb gait abnormality caused by lateral shoulder joint instability. Resolution of the condition is determined by the severity of the nerve trauma (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn dogs, contracture of the infraspinatus muscle has been described in active medium to large size dogs (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Dogs are presented with acute thoracic limb lameness following vigorous activity. The exact aetiology of the condition remains unknown; however, data obtained from electrodiagnostic, and histopathological findings suggest a primary muscle disease (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTo the authors\u0026rsquo; knowledge, traumatic injury of the SSN has not previously been reported in dogs. This case highlights a rare but essential differential diagnosis for unilateral thoracic limb lameness in dogs. Clinical suspicion of traumatic SSN injury should be raised in dogs with history of trauma in cases presented with unilateral thoracic limb lameness and associated muscle atrophy. Advanced imaging and electrodiagnostic studies play a key role to localise the lesion and support the diagnosis, while conservative management could lead to full recovery. This case report demonstrates the clinical presentation of SSN injury in a dog and offers valuable insights into the diagnostic approach, management and prognosis of such cases.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA 4-year-old male neutered Cocker Spaniel was presented to the Orthopaedic Service at a Referral Hospital for further investigation of chronic left thoracic limb lameness. The signs started acutely four weeks prior to presentation as a non-weight bearing lameness following a traumatic event - his left thoracic limb became trapped in a tree whilst exercising off lead. There had been no history of lameness or gait abnormality prior to this incident. Diagnostic investigations performed by the primary veterinarian revealed normal complete blood count and serum biochemistry [Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e,\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e]. Radiographs of the shoulder joints, computed tomography of the thoracic limbs and cervical spine, and arthrocentesis of the left shoulder joint was also performed prior to referral and revealed no abnormalities aside from severe atrophy of the left supraspinatus and infraspinatus muscles. A course of pain relief [robenacoxib 2mg/kg per os (PO) every 24 hours, paracetamol 400mg /codeine 9mg (20mg/kg and 0.45mg/kg respectively) 23mg PO every 8 hours] was prescribed, no improvement of the lameness was reported.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003ctable id=\"Tab1\" border=\"1\"\u003e \u003ccaption\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e\u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003c/colgroup\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\"\u003e \u003cp\u003eTest\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\"\u003e \u003cp\u003eResult\u003c/p\u003e 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\u003cp\u003e10–125\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eALKP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eU/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e23–212\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eGGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eU/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0–11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eTBIL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e\u0026lt; 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eµmol/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0–15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eCHOL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e3.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003emmol/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e2.84–8.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eAMYL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e683\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eU/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e500–1500\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eLIPA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e685\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eU/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e200–1800\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ecPL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eSerum Biochemistry – Catalyst Dx\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003cp\u003e\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\"\u003e\u003c/div\u003e\u003ctable id=\"Tab2\" border=\"1\"\u003e \u003ccaption\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e\u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003c/colgroup\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\"\u003e \u003cp\u003eTest\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\"\u003e \u003cp\u003eResult\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\"\u003e \u003cp\u003eUnit\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\"\u003e \u003cp\u003eReference Interval\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eRBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e8.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^12/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e5.83–9.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eHCT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e52.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e36.6–54.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eHGB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e16.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eg/dL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e12.2–18.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eMCV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e61.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003efL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e55.8–71.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eMCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e19.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ePg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e17.8–28.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eMCHC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e31.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eg/dL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e30.9–38.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eRDW\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e15.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e14.7–17.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%RETIC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eRETIC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e46.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eK/µL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e10.0–110.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eWBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e6.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e5.50–16.90\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%NEU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e65.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%LYM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e19.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%MONO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e11.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%EOS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%BASO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eNEU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e4.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e2.00–12.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eLYM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e1.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.50–4.90\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eMONO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0/79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.30–2.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eEOS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0/19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.10–1.49\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eBASO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ex10^9/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.00–0.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ePLT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e283\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eK/µL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e175–500\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003eMPV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e13.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003efL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ePDW\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e17.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\"\u003e \u003cp\u003ePCT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e0.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eComplete Blood Count (CBC) – LaserCyte\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003cp\u003e\u003c/p\u003e \u003cp\u003eOn presentation, the dog was bright, alert, with an ideal body condition (body weight 17.4kg BCS 5/9). Subjective gait analysis found moderate lameness localised to the left thoracic limb, grade 3/10 (\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e). The observed gait pattern reflected circumduction of the limb during protraction, with abduction of the elbow joint during the weight-bearing phase, similar to alterations seen in dogs with infraspinatus contracture. Upon physical examination, severe muscle atrophy of the left infraspinatus and supraspinatus with complete prominence of the scapula spine was apparent. The triceps, biceps brachii, and brachialis were also mildly atrophied. There was no hyperaesthesia and the left shoulder joint had normal full range of motion with no instability noted. No pain was elicited on deep palpation of the left axilla, and there was no palpable axillary mass. The right thoracic limb was normal. Postural responses were normal, and cutaneous trunci, perineal and withdrawal reflexes were intact. No abnormalities were detected on cranial nerve examination, and there was no pain evident on spinal palpation. At this stage, the main differentials were traumatic, neoplastic or inflammatory lesions (including migrating foreign body neuritis, although it was considered less likely) localized to the left SSN or C5-C7 nerve roots.\u003c/p\u003e \u003cp\u003eMagnetic resonance imaging (MRI) of the caudal cervical and cranial thoracic region was performed using a 1.5 T scanner (Philips Ingenia CX, Philips Healthcare, Best, Netherlands) obtaining T1 weighted, T2 weighted, fat supressed and gradient echo sequences. Gadobutrol (Gadovist) at a dose of 0.1mmol/kg was administered intravenously as a contrast medium. Magnetic resonance imaging revealed focal enlargement of the deep portion of the left SSN at the level of the cranial endplate of C7. The thickened nerve had a moderately heterogenous, but predominantly hyperintense T2W signal intensity, with heterogenous contrast enhancement (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e–\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). The associated left supraspinatus and infraspinatus muscles were markedly reduced in volume with a diffuse, homogenous T2W-hyperintense signal. The right forelimb muscles were unaffected with normal signal intensity and muscle volume. The remainder of the MRI was unremarkable with the exception of multiple, non-compressive, cervicothoracic degenerative, intervertebral disc protrusions.\u003c/p\u003e \u003cp\u003eFollowing the MRI, electromyography (EMG) of the left thoracic limb was performed under general anaesthesia. Localised, abnormal spontaneous electrical activity consisting of positive sharp waves and fibrillation potentials was recorded in the infraspinatus and supraspinatus muscles only (graded as + + in the infraspinatus and +++ in the supraspinatus; range 0 - ++++ based on Kimura 2001) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). This allowed us to exclude disuse as a cause for the atrophy and was most consistent with chronic denervation of the muscles innervated by the SSN. Other muscles evaluated were all normal (electrically silent) including the left biceps, triceps and subscapularis muscles which are innervated by the musculocutaneous, radial and subscapularis nerves respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eGiven the history and diagnostic findings, our presumptive diagnosis was neurogenic atrophy of the infraspinatus and supraspinatus muscles caused by a traumatic neuropathy of the left SSN. A peripheral nerve sheath tumour was also given as a differential, and we discussed with the owners that if clinical signs progressed repeat imaging would be warranted. Conservative management was recommended with rest and controlled increase exercise for the following 12 weeks. At this stage the patient was not considered clinically painful therefore analgesia was not indicated.\u003c/p\u003e \u003cp\u003eFollow-up assessment was carried out after 12 weeks, when the dog exhibited a marked improvement in clinical signs. Orthopaedic examination was normal with no lameness at a walk or trot. Substantial palpable improvement of the muscle volume of infraspinatus and supraspinatus was documented, although moderate atrophy remained. No abnormalities were reported upon orthopaedic and neurological assessments. A repeat MRI to further assess the previous lesion in the SSN was recommended but declined by the owner given the dog’s clinical improvement. At the last telephone communication with the owner 9 months after injury, they reported that the dog’s lameness remained in complete remission, he had returned to normal activity and they had no other concerns.\u003c/p\u003e "},{"header":"Discussions and Conclusions:","content":"\u003cp\u003eTo the authors’ knowledge, this is the first case report of a traumatic SSN injury causing supraspinatus/infraspinatus muscle atrophy in a dog. Several studies have documented nerve injuries affecting the thoracic limb in small animals, with brachial plexus injury resulting from road traffic accidents most common (\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e–\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e). The thoracic limb of small animals is mobile against the body wall and it has been suggested that the nerve roots are susceptible to traumatic avulsion at this level as they are relatively vulnerable to stretching forces (\u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e). Specific injuries to the SSN are most frequently reported in horses, particularly in draft breeds, and are often attributed to repeated trauma from ill-fitting harnesses (\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e). The location of the nerve near the cranial border of the scapula predisposes it to direct compression injuries (\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e). In horses, SSN injury is typically diagnosed presumptively based on the key clinical findings of supraspinatus and infraspinatus atrophy; however, the clinical suspicion of SSN injury can be supported ultrasonography and EMG (\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e). In the case presented here, the neuroanatomical localization, MRI findings and EMG were all consistent with a lesion of the SSN. The acute onset history associated with trauma and diagnostic findings lead to a presumptive diagnosis of traumatic SSN injury which is strongly supported by the subsequent clinical resolution.\u003c/p\u003e\u003cp\u003eAlthough both CT and MRI are useful imaging modalities for assessment of neuromuscular and musculoskeletal structures, MRI is by far the more superior modality for assessment of specific soft tissue structures. In particular, allows more accurate and detailed differentiation of soft tissue structures, such as nerves, from the adjacent soft tissue structures and vasculature (\u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e). Various studies in both veterinary and human medicine have demonstrated the enhanced diagnostic quality of MRI images compared with CT for peripheral nerve pathology (\u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e–\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e). In the context of imaging of the brachial plexus, CT is limited by its restriction to axial plain acquisition, and by artifacts associated with the adjacent tissues of the shoulder (\u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e–\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e). In this case, CT imaging alone was inconclusive whereas a focal lesion within the left SSN was visible on the MRI study. Our findings are consistent with those described in dogs affected by inflammatory and traumatic lesion of the brachial plexus (\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIncreased T2W hyperintensity has been associated with several peripheral neuropathies including degenerative, traumatic and neoplastic conditions in both humans and dogs (\u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e).Nonetheless, increased nerve T2W hyperintensity remains a nonspecific finding. Interestingly, peripheral neuropathies demonstrate varying degrees of enhancement in both species and in some cases no enhancement is observed. These studies highlight that while MRI findings can be supportive of a neuropathy/nerve injury, changes in signal intensity such as T1W hyperintensity or contrast enhancement are not specific for the underlying cause (\u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e). Another study shown that normal sciatic and femoral nerves in dogs do not show contrast enhancement on MRI (\u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e). Thus, it has been suggested to use fat-suppression sequences in post-contrast T1W images when visualizing diseased nerves, as this allows differentiation of affected nerves from the surrounding fat based on their contrast enhancement (\u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e). In the presented case, the SSN exhibited both T2W hyperintensity and contrast enhancement and therefore suggestive of a peripheral neuropathy.\u003c/p\u003e\u003cp\u003eMuscle atrophy due to denervation is rapid and severe (\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e), electromyography found spontaneous activity in the supraspinatus and infraspinatus muscles which is also consistent with denervation due to a SSN lesion. Fibrillation potentials and positive sharp waves as seen in this case are non-specific findings and can also be seen in myopathies (\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e–\u003cspan class=\"CitationRef\"\u003e32\u003c/span\u003e); however, our clinical examination and radiological findings make this less likely. Fibrillations and positive sharp waves associated with denervation arise due to hypersensitivity of myofibres secondary to sarcolemmal destabilization and develop typically 7–10 days following the injury (\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e). In the acute and subacute phase, reduced or absent voluntary motor unit action potentials (MUAPs) may be detected on EMG, as a result of loss of functional motor units (\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e). In contrast, during recovery, MUAPS become polyphasic, with prolonged-duration, and increased-amplitude. As hallmarks of re-innervation and collateral sprouting from surviving axons. In the line with this, spontaneous activity typically decreases (\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e). Conscious EMG was not performed in our case however the presence of marked spontaneous activity suggests denervation of these muscles at the time of the examination. The other muscles of the left thoracic limb were normal on EMG indicating that the milder atrophy noted throughout the limb was due to disuse.\u003c/p\u003e\u003cp\u003ePeripheral nerve sheath tumor (PNST) was one possible differential diagnosis. Dogs with PNST are commonly presented with similar signs: lameness and muscle atrophy associated with the anatomic location of the lesion and the chronicity of the disease (\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e). The brachial plexus and the lumbosacral plexus are the most frequently affected regions (\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e). PNST in dogs have a guarded to poor prognosis, although outcomes can significantly improve following complete surgical excision or volumetric modulated arc radiation therapy (\u003cspan class=\"CitationRef\"\u003e35\u003c/span\u003e). In a recent study investigating dogs with presumptive and confirmed PNSTs, regardless of treatment, median survival time was 4 months (range 2 weeks to 2 years, 8 months) (\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e). The study included different types of nerve sheath tumors (NSTs): cranial NSTs, NST with spinal canal invasion, and NSTs external to the spinal canal. Consistently, all dogs showed progressive clinical signs and were eventually euthanized (\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e). Although disease progression and imaging findings alone can be highly suggestive of neoplasia, a definitive diagnosis of PNST requires histopathological evaluation (\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e). In the current case, due to the invasive nature of the procedure and potential morbidity associated with fascicular nerve biopsy, histopathological evaluation was not considered clinically indicated following initial investigations. Instead, a follow-up MRI to monitor disease progression was recommended. Due to the patient’s return to normal mobility, this was declined by the owner. Nevertheless, given the dog’s resolution of lameness and the restoration of the muscle volume at 9 months, these findings would support a focal nerve lesion, secondary to trauma, not consistent with a PNST.\u003c/p\u003e\u003cp\u003eTo conclude, this case reports the cause of thoracic limb lameness with severe isolated muscle atrophy following a traumatic injury to the SSN which responded to conservative management. Trauma of the SSN, although rare, should be included in the differential diagnosis of the dogs with unilateral thoracic limb lameness with severe infraspinatus and supraspinatus atrophy.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCT Computed tomography\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePO Per os\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSSN Suprascapular nerve\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMRI Magnetic resonance imaging\u003c/p\u003e\n\u003cp\u003eEMG electromyography\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePNST Peripheral nerve sheath tumor\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNSTs Nerve sheath tumors\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA. E. Pontikaki: conceptualisation, investigation, writing \u0026ndash; original draft, writing \u0026ndash; review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003eS. Mella: investigation, writing \u0026ndash; original draft, writing \u0026ndash; review \u0026amp; editing.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eG. Walmsley: investigation, writing \u0026ndash; review \u0026amp; editing.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eR. T. Bentley: conceptualisation, investigation, writing \u0026ndash; review \u0026amp; editing.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eT. Cox: conceptualisation, investigation, supervision, writing \u0026ndash; review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eMedivet Ltd.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e: No datasets were generated or analysed during the current study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eNot applicable; procedures were part of standard clinical care with informed owner consent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eUemura EE. Fundamentals of Canine Neuroanatomy and Neurophysiology. 1st ed. 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Veterinary Sciences [Internet]. 2024 May [cited 2025 Apr 14];11(5):192. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.mdpi.com/2306-7381/11/5/192\u003c/span\u003e\u003cspan address=\"https://www.mdpi.com/2306-7381/11/5/192\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTekavec K, Švara T, Knific T, Gombač M, Cantile C. Histopathological and Immunohistochemical Evaluation of Canine Nerve Sheath Tumors and Proposal for an Updated Classification. Vet Sci. 2022;9(5):204.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-veterinary-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Veterinary Research](http://bmcvetres.biomedcentral.com/)","snPcode":"12917","submissionUrl":"https://submission.nature.com/new-submission/12917/3?","title":"BMC Veterinary Research","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8916595/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8916595/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground: Traumatic suprascapular nerve injury is well recognized in both horses and humans, however, the condition has not been reported in dogs. The suprascapular nerve innervates the infraspinatus and supraspinatus muscles, and trauma of the nerve can result in profound atrophy of these muscles and mechanical lameness.\u003c/p\u003e\n\u003cp\u003eCase presentation: A 4-year-old male neutered Cocker Spaniel was presented with moderate lameness of the left thoracic limb and severe muscle atrophy of the supraspinatus/infraspinatus muscles. Gait alterations included abduction of the elbow joint during the weight bearing phase, resembling those observed in dogs with infraspinatus contracture. Magnetic resonance imaging of the caudal cervical spine and left thoracic limb revealed segmental enlargement of the left suprascapular nerve at the level of the cranial endplate of C7 and marked diffuse homogenous signal changes and atrophy of the left supraspinatus and infraspinatus muscles. Electromyography revealed moderate to severe spontaneous activity isolated to the supraspinatus and infraspinatus muscles consistent with denervation. The patient was presumptively diagnosed with traumatic suprascapular nerve injury and, following a period of exercise restriction, exhibited a marked improvement in clinical signs. The owner reported a return to normal gait and exercise at 9 months follow-up.\u003c/p\u003e\n\u003cp\u003eConclusion: To the authors’ knowledge, this is the first case report to describe the presentation, investigations and management of suprascapular nerve injury in a dog. Traumatic injury of the suprascapular nerve, although rare, should be considered in dogs presented with unilateral thoracic limb lameness. Accurate diagnosis and appropriate management of the condition could lead to favourable outcome.\u003c/p\u003e","manuscriptTitle":"Resolution of thoracic limb lameness associated with traumatic suprascapular neuropathy in a dog: case report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-18 08:31:10","doi":"10.21203/rs.3.rs-8916595/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-03-12T08:55:14+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-12T08:48:09+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-25T09:09:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-24T08:28:53+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Veterinary Research","date":"2026-02-24T08:23:38+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-veterinary-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Veterinary Research](http://bmcvetres.biomedcentral.com/)","snPcode":"12917","submissionUrl":"https://submission.nature.com/new-submission/12917/3?","title":"BMC Veterinary Research","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e7cd2b99-5d8a-490e-bc3d-b076520223fd","owner":[],"postedDate":"March 18th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-18T08:31:10+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-18 08:31:10","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8916595","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8916595","identity":"rs-8916595","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}