Bone oedema-like lesions at the enthesis of distal interphalangeal joint collateral ligaments: magnetic resonance imaging findings, management and outcome.

Bone oedema-like lesions at the enthesis of distal interphalangeal joint collateral ligaments: magnetic resonance imaging findings, management and outcome. | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL Equine Veterinary Education This is a preprint and has not been peer reviewed. Data may be preliminary. 3 January 2025 V1 Latest version Share on Bone oedema-like lesions at the enthesis of distal interphalangeal joint collateral ligaments: magnetic resonance imaging findings, management and outcome. Authors : Francesca Cavallier 0009-0009-6321-6398 [email protected] , Federica Cantatore 0000-0003-1745-6146 , Marco Marcatili 0000-0002-5449-6780 , and M. Biggi Authors Info & Affiliations https://doi.org/10.22541/au.173586947.70644878/v1 437 views 222 downloads Contents Abstract Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Bone oedema-like lesion is characterized by hyperintense signals in short tau inversion recovery (STIR) sequences on magnetic resonance imaging (MRI). The pattern of bone oedema-like lesions involving the enthesis of the collateral ligament (CL) of the distal interphalangeal joint (DIPJ) has not been investigated as a cause of lameness in horses. This pattern was detected in 10 forelimbs of nine horses, involving the medial collateral fossa of the distal phalanx in six feet. The STIR signal was graded as ‘severe’ in two feet, ‘moderate’ in two feet, and ‘mild’ in six feet, and involved the dorsal two-thirds of the fossa in seven feet. The bone lesion was the only lesion in six feet, while in three feet, the ipsilateral CL presented abnormalities. Follow-up MRI was available for three horses and revealed a reduction of the STIR signal. Five horses returned to a lower level of athletic activity, while four returned to the same or a higher level. Bone oedema-like lesion at the CLs enthesis is a potential cause of lameness even if the ipsilateral CL appears normal. The prognosis for return to athletic activity is good, although further studies with a larger number of horses are required. Bone oedema-like lesions at the enthesis of distal interphalangeal joint collateral ligaments: magnetic resonance imaging findings, management and outcome. RUNNING TITLE: Bone oedema-like lesions causing lameness. AUTHORS F. Cavallier 1 , F. Cantatore 2 , M. Marcatili 2 , M. Biggi 2 1 = Department of Veterinary Medicine and Animal Sciences, University of Milan, Lodi, Italy 2 = Pool House Equine Hospital, IVC Evidensia, Rykneld Street, Fradley, WS13 8RD, United Kingdom SUMMARY Bone oedema-like lesion is characterized by hyperintense signals in short tau inversion recovery (STIR) sequences on magnetic resonance imaging (MRI). The pattern of bone oedema-like lesions involving the enthesis of the collateral ligament (CL) of the distal interphalangeal joint (DIPJ) has not been investigated as a cause of lameness in horses. This pattern was detected in 10 forelimbs of nine horses, involving the medial collateral fossa of the distal phalanx in six feet. The STIR signal was graded as ‘severe’ in two feet, ‘moderate’ in two feet, and ‘mild’ in six feet, and involved the dorsal two-thirds of the fossa in seven feet. The bone lesion was the only lesion in six feet, while in three feet, the ipsilateral CL presented abnormalities. Follow-up MRI was available for three horses and revealed a reduction of the STIR signal. Five horses returned to a lower level of athletic activity, while four returned to the same or a higher level. Bone oedema-like lesion at the CLs enthesis is a potential cause of lameness even if the ipsilateral CL appears normal. The prognosis for return to athletic activity is good, although further studies with a larger number of horses are required. KEYWORDS: MRI, collateral ligament of the distal interphalangeal joint, bone oedema-like lesion , enthesopathy, desmopathy. INTRODUCTION The collateral ligaments (CLs) of the distal interphalangeal joint (DIPJ) originate and insert in depressions on the middle and distal phalanges (collateral fossae ), close to the joint margins (Denoix, 1998). The DIPJ is a hinge joint with motion in the sagittal plane, and the CLs function as part of the supporting apparatus of the DIPJ. Non-physiologic rotational movements or lateromedial movements of the joint can injure the CLs (Denoix, 1999). Therefore, exercise on uneven ground, foot imbalance, angular limb deformities, or tight turns may predispose horses to this condition (Zubrod, 2005). Desmopathy of the CLs of the DIPJ is a common cause of foot lameness in horses undergoing magnetic resonance imaging (MRI). A study by Dyson et al. (2005) showed that CL desmopathy was the second most common (31%) pathology in a large cohort of horses, often affecting the medial CL in the forelimb (Dyson, 2004). A more recent study found CL desmopathy to be the most significant imaging finding in 15% of Warmblood horses diagnosed with foot lameness (Gutierrez-Nibeyro et al., 2020). MRI is considered the gold standard for diagnosing desmopathy of the CLs of the DIPJ, as it allows for the characterization of the extent of the damage and concurrent pathologies, including bone damage (Dyson et al., 2004; Zubrod, 2005). Osseous abnormalities at the enthesis of the CLs of the DIPJ, including increased signal intensity in short tau inversion recovery (STIR), endosteal irregularity, enthesous new bone, and osseous cyst-like lesions (OCLLs), have been previously reported (Dakin et al., 2009). A prevalence of 45.7% of osseous pathology directly related to CL injury was identified. Although these abnormalities did not affect the prognosis, the different types of osseous pathologies were not evaluated separately. Bone marrow oedema-like lesions were first described in the human knee and were defined as regions of transient increase in bone marrow water content consequent to trauma (Yao and Lee, 1988). In the absence of bone marrow in the distal phalanx, the term ‘bone oedema-like lesion’ was used in this manuscript. This pattern is characterized by low signal intensity on T1-weighted (W) gradient echo (GRE) sequences and hyperintensity on T2*-W GRE, T2-W fast spin echo (FSE), and STIR images (Powell, 2010). Commonly found in the navicular bone (Dyson et al., 2005), these lesions have also been reported in both distal and middle phalanges (Dyson et al., 2005; Olive, 2009) and in the metaphysis and diaphysis of the third metacarpal bone (Powell, 2010). Bone oedema-like lesions within the collateral fossa are the most frequent type of osseous injury associated with CL pathology, occurring in 7.3% of feet diagnosed with CL desmopathy (Dakin et al., 2009; Dyson et al., 2004). While much attention has been paid to desmopathy of the CLs of the DIPJ and their associated osseous abnormalities, we identified a series of cases in which the bone oedema-like lesion at the enthesis of the CLs was considered the major cause of lameness. The objectives of the current study were to describe the distribution of the bone oedema-like lesion at the level of the proximal or distal enthesis of the CLs and to describe clinical findings, including outcomes and prognosis associated to it. METHODS Horses undergoing MRI of the foot at XXXXXXXX (blinded for review) between September 2016 and September 2023 were considered. Horses were included if the lameness was localized to the foot by diagnostic anaesthesia and CL enthesopathy was reported. Cases were selected if bone oedema-like lesion at the enthesis of the CL of the DIPJ was considered a major contributor to the lameness. MRIs were obtained using a standing low-field (0.27 Tesla) system (Hallmarq Veterinary Imaging) as previously described in the literature (Mair et al., 2005; Sherlock et al., 2007). All horses were sedated with an α2 agonist agent and morphine sulphate for the examination. A standard protocol, including T1-weighted (W) gradient echo (GRE), T2*-W GRE, T2-W fast spin echo (FSE), and short tau inversion recovery (STIR) sequences, was obtained in sagittal, transverse, and frontal planes for both front feet of all horses. All included studies were prospectively evaluated by a board-certified radiologist (X.X). All images were retrospectively re-evaluated for the presence of pathology of the collateral fossa (CF) and CLs of the DIPJ. Increased STIR signal intensity in the collateral fossa was subjectively classified as ‘mild,’ ‘moderate,’ or ‘severe’ (Figure 1), and its distribution was classified as involving the dorsal, middle, and palmar thirds of the CF or a combination of these. Thickening of the cortex of the CF and irregularities of its endosteal margin were subjectively graded as ‘mild,’ ‘moderate,’ or ‘severe’ on frontal T1-W GRE sequences. The presence of an indentation in the fossa, defined as a T1 linear hyperintensity extending through the cortex of the CF, was also recorded. If an osseous cyst-like lesion in the fossa was the predominant MRI feature, the case was excluded from the study. The presence of concurrent pathologies was extrapolated from the original report. Details of the treatment and rehabilitation program were obtained from the clinical history of the horses. When follow-up MRI was performed, the evolution of the bone oedema-like lesion was evaluated by comparison with the original MRI. CASES HISTORY and CLINICAL FINDINGS During the study period, 2016 MRI studies of the feet were performed. Of these, nine horses met the inclusion criteria, with ten forelimbs being affected (0.5% of the cases). The group included 2 Warmbloods, 2 Cobs, 1 Irish Sport Horse, 1 Gelderland, 1 Connemara, 1 Welsh, and one Oldenburg. Ages ranged from 6 to 20 years (mean 12.3 years). There were six geldings, two mares, and one stallion. Six horses were used for general riding and three for dressage. Eight horses presented with unilateral lameness (six in the right forelimb and two in the left forelimb), and one horse presented with bilateral forelimb lameness. No significant localizing signs, such as swelling, were identified in any of the horses. In two cases (case 1 and case 6), there was a history of trauma; Case 1 became lame after spooking during a hack, and case 6 sustained an unspecified field accident. The history and clinical findings for each horse are summarized in Table 1. MAGNETIC RESONANCE FINDINGS Bone oedema-like lesions involved the medial collateral fossa (CF) of the distal phalanx in six feet and the lateral in four feet. In one case (Case 6), the medial CF on both limbs was affected. In another case (Case 9), bone oedema-like lesions were concurrently observed at the distal and proximal enthesis of the medial CL. The STIR hyperintensity was subjectively graded as severe in two feet, moderate in two feet, and mild in six feet. It involved the entire dorsopalmar extent of the fossa in three cases, the mid and dorsal thirds in three cases, and the palmar aspect or middle third in one case. Thickening and endosteal remodelling of the CF were seen in most cases, with changes being symmetrical medio/laterally, except in cases with severe endosteal changes. These were identified in two horses ipsilateral to the bone oedema pattern. An indentation of the fossa was identified in four feet of three horses; in two horses, the changes were biaxial, while in case 6, bilateral indentations were seen medially, ipsilateral to the bone oedema. In three feet, there was an alteration in size and signal intensity of the ipsilateral CL of the DIPJ; the changes were mild in all but one case (case 7). In six feet (62.5%), the ipsilateral CL was normal, while in the remaining feet, the CL presented pathologies likely contributing to the lameness. Four horses (44.4%) had concurrent mild pathologies within the foot. Case 2 had mild irregularities on the lateral lobe of the deep digital flexor tendon in the presesamoidean region. Case 2 and case 6 had moderate DIPJ osteoarthritis, and case 6 also had fragmentation of the extensor process of the distal phalanx. A distal border fragment was seen on the navicular bone of case 3, with no significant associated navicular bone disease. Case 9 had biaxial desmopathy of the collateral sesamoidean ligaments and effusion of the navicular bursa. TREATMENT All horses were treated with corrective shoeing and box rest, combined with controlled walking exercises, predominantly in a straight line, for three to eight months. Additionally, three horses received injections of 10 mg triamcinolone acetonide into the DIPJ, and one horse was treated with allogenic stem cells. One horse underwent extracorporeal shock wave therapy (ESWT) with three treatments at two-week intervals. Four horses received oral non-steroidal anti-inflammatory drugs, and one horse received an intravenous infusion of tiludronate (1mg/kg). OUTCOME Follow-up data (>12 months) were available for all horses. MRI follow-up was available for three of the cases at 54, 116, and 322 days (mean 164 days) after diagnosis, revealing a reduction in bone oedema (Figure 2). In one horse (case 2), an osseous cyst-like lesion developed at the site of the indentation detected at the initial examination. Six cases underwent follow-up re-examination performed by the referring veterinary surgeon. All horses resumed ridden work. Five horses returned to a lower level of athletic activity compared to before the injury, two horses returned to the same level, and two horses returned to a higher level of athletic activity. There was no correlation between the degree of lameness and the grade of hyperintense STIR signal on MRI images as subjectively assessed. Additionally, there was no association between the grade and extent of STIR hyperintensity and the outcome. DISCUSSION Our results are in line with previous literature (Beasley et al., 2020; Dakin et al., 2009), showing that osseous pathology is more common at the insertion of the CLs compared to the origin and involving the medial collateral fossa . Despite the association between CL injuries and bone oedema-like lesions at their enthesis has been previously reported (Dakin et al.,2009), we identified a small number of cases where bone pathology was the predominant abnormality. In six out of nine horses the ipsilateral CL appeared normal on low-field MRI. It has been proposed that osseous pathology at the enthesis can exist without associated CL pathology visible on MRI. However, since MRI may underestimate CL pathology, mild changes could still be present in ligaments classified as normal on MRI (Dyson et al., 2008).The dorsal-palmar distribution of the STIR signal in the fossa has not been previously reported. However, it has been observed that osseous cyst-like lesions are typically located in the palmar aspect of the CF (Dakin et al., 2009). The mid and dorsal distribution of the signal intensity identified in this study may be related to joint instability. Anatomical differences in the direction of ligament fibers may also predispose fluid-type lesions to develop dorsally, while resorptive lesions are located more palmarly. In our study, bone oedema-like lesions had a low prevalence, suggesting that this lesion is uncommon. However, some horses with such lesions may have been excluded because other significant foot pathology was identified. Therefore, the actual prevalence of the lesion may be underestimated and not comparable with results from other studies. All nine horses included in the study were found to have bone oedema-like lesions at the insertion of the CL of the DIPJ, which was the most significant finding of the MRI study. Unexpectedly, there was no association between the degree of lameness and the severity of the imaging findings. The study is a retrospective case series, and therefore, the treatments were tailored to the referring veterinary surgeons’ preferences. Future studies with a larger population of horses are required to investigate the cause of this pathology and the efficacy of different treatments. Unfortunately, follow-up MRI was not performed in all the horses; therefore, the duration and evolution of STIR hyperintensity were not determined in all cases. However, resolution was demonstrated in the horses that did undergo follow-up MRI. Considering that the lameness was acute in all cases, we presumed that the bone oedema-like lesion was a stress reaction at the level of the enthesis of the CL. Although histological investigation of the present cases was not possible, the osseous changes observed on MRI were pathological, as they are not observed in sound horses. Nevertheless, the signal reduction in the available follow-up MRI corresponded with the clinical improvement of the horses. In conclusion, bone oedema-like lesions at the enthesis of the CL of the DIPJ should be considered a potential cause of lameness, even if the ipsilateral CL appears normal. Magnetic resonance imaging is essential to obtain a definitive diagnosis and characterize this lesion. The prognosis for return to athletic activity appears to be good to excellent, although further studies with a larger number of horses are required. Authors’ declaration of interests No conflicts of interest have been declared. Ethical animal research Retrospective clinical case study, no approval needed. The owners’ consent to participate to the study was retrospectively obtained. Acknowledgements The Authors would like to thank the referring veterinary surgeons for providing the cases. REFERENCES American Association of Equine Practitioners (2020). Lameness Exams: Evaluating the Lame Horse. www.AAEP.Org. https://aaep.org/horsehealth/lameness-exams-evaluating-lame-horse. Dakin, S.G., Dyson, S.J., Murray, R.C. and Tranquille, C. (2009). Osseous abnormalities associated with collateral desmopathy of the distal interphalangeal joint: Part 1. Equine Veterinary Journal, 41(8), pp.786-793. Denoix, J.-M. (1998). The collateral ligaments of the distal interphalangeal joint: anatomy, roles and lesions. Hoofcare Lameness, 70, pp.29-32. Denoix, J.-M. (1999). Ligament injuries of the distal interphalangeal joint in horses. Proceedings of the 6th World Equine Veterinary Association Congress, Paris, France, pp.41-46. Dyson, S.J. (1998). The puzzle of distal interphalangeal joint pain. Equine Veterinary Education, 10(3), pp.119-125. Dyson, S.J., Murray, R., Schramme, M. and Branch, M. (2004). Collateral desmitis of the distal interphalangeal joint in 18 horses (2001–2002). Equine Veterinary Journal, 36, pp.160-166. Dyson, S.J., Murray, R. and Schramme, M.C. (2005). Lameness associated with foot pain: results of magnetic resonance imaging in 199 horses (January 2001‐December 2003) and response to treatment. Equine Veterinary Journal, 37(2), pp.113-121. Dyson, S., Blunden, T. and Murray, R. (2008). The collateral ligaments of the distal interphalangeal joint: magnetic resonance imaging and postmortem observations in 25 lame and 12 control horses. Equine Veterinary Journal, 40(6), pp.538-544. Gutierrez‐Nibeyro, S.D., Werpy, N.M., Gold, S.J., Olguin, S. and Schaeffer, D.J. (2020). Standing MRI lesions of the distal interphalangeal joint and podotrochlear apparatus occur with a high frequency in warmblood horses. Veterinary Radiology & Ultrasound, 61(3), pp.336-345. Haussler, M.L., Rantanen, N.W. and Modransky, P.D. (1982). Ultrasound examination of the distal interphalangeal joint, navicular bursa, navicular bone, and deep digital tendon. Journal of Equine Veterinary Science, 2, pp.95-97. Mair, T.S., Kinns, J., Jones, R.D. and Bolas, N.M. (2005). Magnetic resonance imaging of the distal limb of the standing horse. Equine Veterinary Education, 17(2), pp.74-78. Mair, T.S. and Sherlock, C.E. (2008). Collateral desmitis of the distal interphalangeal joint in conjunction with concurrent ossification of the cartilages of the foot in nine horses. Equine Veterinary Education, 20, pp.485-492. McDiarmid, A.M. (1998). Distal interphalangeal joint lameness in a horse associated with damage to the insertion of the lateral collateral ligament. Equine Veterinary Education, 10, pp.114-118. Olive, J., Mair, T.S. and Charles, B. (2009). Use of standing low‐field magnetic resonance imaging to diagnose middle phalanx bone marrow lesions in horses. Equine Veterinary Education, 21(3), pp.116-123. Powell, S.E., Ramzan, P.H.L., Head, M.J., Shepherd, M.C., Baldwin, G.I. and Steven, W.N. (2010). Standing magnetic resonance imaging detection of bone marrow oedema‐type signal pattern associated with subcarpal pain in 8 racehorses: a prospective study. Equine Veterinary Journal, 42(1), pp.10-17. Sage, A.M. and Turner, T.A. (2002). Ultrasonography of the soft tissue structures of the equine foot. Equine Veterinary Education, 4, pp.278-283. Sherlock, C.E., Kinns, J. and Mair, T.S. (2007). Evaluation of foot pain in the standing horse by magnetic resonance imaging. Veterinary Record, 161(22), pp.739-744. Yao, L. and Lee, J.K. (1988). Occult intraosseous fracture: detection with MR imaging. Radiology, 167, pp.749-751. Zubrod, C.J., Farnsworth, K.D., Tucker, R.L. and Ragle, C.A. (2005). Injury of the collateral ligaments of the distal interphalangeal joint diagnosed by magnetic resonance. Veterinary Radiology & Ultrasound, 46(1), pp.11-16 Figure 1 Dorsal STIR sequences showing mild (case 7), moderate (case 6) and severe (case 2) signal intensity in the collateral fossa. Figure 2 Dorsal and transverse STIR sequences of the RF foot of case 1, medial is to the right of the image, initial and follow-up images. Note the intense STIR signal intensity involving the mid and dorsal third of the fossa (arrowheads) which has resolved in the follow-up images (arrow). TABLE 1: Summary of clinical history and findings from 7 horses with bone marrow oedema-type pattern at enthesis of the collateral ligaments of the distal interphalangeal joint. 1 6 F Oldenburg Gr RF Y 2/5 AAEP Ne I > 50% NP Sound 2 16 S Gelderland D RF N 2/5 AAEP - NP NP Sound 3 9 G Welsh Gr RF N 2/5 AAEP Ne I > 50% NP Sound LF 2/5 AAEP Ne I > 50% NP Sound 4 10 G Connemara Gr RF N 2/5 AAEP - NI NP Sound 5 10 G Irish Sport Horse Gr RF N 2/5 AAEP - I > 50% PI Sound 6 20 G Warmblood D RF Y 2/5 AAEP - NP NP Sound 7 14 G Cob Gr RF N 2/5 AAEP - NP NP Sound Lameness graded on the AAEP 0-5 scale (AAEP, 2020). G = gelding; F = mare; S = stallion; Gr = general riding; D = dressage; RF = right forelimb; LF = left forelimb; Y = yes; N = no; Ne = negative; NP = not performed, I = improvement; PI = partial improvement; NI = no improvement. Information & Authors Information Version history V1 Version 1 03 January 2025 Copyright This work is licensed under a Non Exclusive No Reuse License. Collection Equine Veterinary Education Keywords bone oedema-like lesion collateral ligament of the distal interphalangeal joint desmopathy enthesopathy mri Authors Affiliations Francesca Cavallier 0009-0009-6321-6398 [email protected] University of Milan View all articles by this author Federica Cantatore 0000-0003-1745-6146 Pool House Equine Clinic View all articles by this author Marco Marcatili 0000-0002-5449-6780 Pool House Equine Clinic View all articles by this author M. Biggi Pool House Equine Clinic View all articles by this author Metrics & Citations Metrics Article Usage 437 views 222 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Francesca Cavallier, Federica Cantatore, Marco Marcatili, et al. 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