Surgical approach to malunion of midshaft clavicle fracture with ipsilateral acromioclavicular joint injury

Surgical approach to malunion of midshaft clavicle fracture with ipsilateral acromioclavicular joint injury | 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 Surgical approach to malunion of midshaft clavicle fracture with ipsilateral acromioclavicular joint injury Morteza Gholipour, Arman Namazi, Bahar Behnam, Zahra Kazemi Ferezghi, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7490637/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The combination of midshaft clavicle fracture and ipsilateral acromioclavicular joint (ACJ) injury is rare, with few cases documented over the past three decades. Recent studies suggest a higher incidence of approximately 6.8% among clavicle fractures. Treatment approaches vary, but surgical interventions, such as double plate fixation and ligament repair, have shown promising functional outcomes. Risk factors include ipsilateral scapular body fractures. Standardized treatment protocols are yet to be established, but surgical management appears effective. This report presents a 40-year-old man with a 6-month-old malunited midshaft clavicle fracture and chronic AC joint separation, treated with corrective osteotomy and ligament reconstruction, highlighting the rationale for surgical intervention. midshaft clavicle fracture acromioclavicular joint injury ipsilateral surgical management ORIF hook plate coracoclavicular ligament reconstruction concomitant injury plate fixation ligament reconstruction Figures Figure 1 Figure 2 Introduction Clavicle fractures are common injuries, accounting for roughly 2–5% of all adult fractures ( 1 ). The majority of these (≈ 70–80%) occur in the midshaft of the clavicle ( 1 ). Many midshaft fractures are traditionally managed nonoperatively, but displaced fractures often heal with shortening or angulation. When the clavicle heals in malalignment, the resulting malunion can cause a spectrum of symptoms ( 2 ). In fact, about 15–20% of displaced midshaft clavicle fractures treated nonoperatively ultimately become clinically symptomatic malunions ( 2 ). Average shortening after a displaced midshaft fracture is around 1.2 cm (with reported ranges up to 3 cm), and shortening beyond ~ 1.5–2 cm is generally considered critical for developing symptoms ( 1 ). Shoulder and scapular symptoms : Clavicular malunion alters the normal shoulder girdle mechanics. Patients often develop a “droopy,” asymmetric shoulder with prominence of the clavicle or shoulder peak ( 2 ). Shoulder blade (scapular) winging or protraction may be seen due to changes in the resting scapular position ( 1 ). These changes lead to functional problems with overhead motion and pain on lying on the shoulder ( 1 ). Muscle weakness and fatigue : Shortening of the clavicle disrupts muscle balance, leading to weakness or easy fatigability of the shoulder girdle ( 2 ). Patients may report reduced strength, difficulty carrying loads (e.g. backpacks), or persistent shoulder fatigue. Neurologic and cosmetic issues : Large malunions with significant callus formation can sometimes compress neurovascular structures (thoracic outlet syndrome) or cause cosmetic complaints due to the shoulder deformity ( 1 , 2 ). Acromioclavicular (AC) joint injuries are also relatively common, particularly in young athletes and following direct blows or falls onto the shoulder ( 3 ). These injuries are classified by the Rockwood system (types I–VI) based on the severity of AC and coracoclavicular ligament disruption and displacement ( 4 ). Low-grade injuries (types I–II) are typically treated without surgery, but high-grade dislocations (types IV–VI) produce a noticeable shoulder deformity (posterior or inferior displacement of the clavicle) and usually require surgical stabilization. A classic feature of severe AC separations is a pronounced shoulder droop and increased coracoclavicular distance on x-ray ( 5 ). The simultaneous occurrence of a clavicle shaft fracture and ipsilateral AC joint dislocation is exceedingly rare ( 6 ). Most AC joint separations occur with lateral clavicle fractures rather than midshaft fractures ( 3 ). Combined midshaft-clavicle and AC injuries have only been reported in a few isolated case studies ( 1 , 3 ), and there are no clear guidelines for their optimal management ( 6 ). Missed or untreated, the combination can lead to chronic pain, persistent deformity, and functional impairment of the shoulder. In this report, we present a 40-year-old man with a 6-month-old malunited midshaft clavicle fracture associated with a chronic AC joint separation. He had shoulder droop, scapular winging, and reduced shoulder strength and range of motion. The patient was managed with a clavicular corrective osteotomy (Z-lengthening) and reconstruction of the AC joint ligaments. This case highlights the uncommon nature of combined clavicle malunion with AC joint injury and discusses the rationale for surgical reconstruction in restoring shoulder anatomy and function. Case report A 40-year-old man presented to our department 6 months after sustaining a left shoulder injury from a fall. The patient presented with a left-sided midshaft clavicle fracture progressed to malunion and shortening with concomitant ipsilateral AC joint injury resulting in a 3-cm diastasis. Physical examination showed a dropped left shoulder (Fig. 1–1), scapular winging (Fig. 1–2), anterosuperior positioning of the left upper extremity (Fig. 1–3), ipsilateral reduced muscle strength, and diminished left shoulder range of motion. Compared to the opposite side, the medial border of the left scapula was closer to the midline. In the beach chair position under scalene nerve block anesthesia, a classic open surgical approach was used for fixation of the clavicle fracture extending to the AC joint. First, subperiosteal elevation of the muscular layer from the malunited clavicle bone was performed; then the AC joint gap was debrided of any fibrotic tissues; after that, the malunion site underwent Z-lengthening osteotomy; achieving 3 cm of length restoration and reconstructing the AC joint. After Z- lengthening osteotomy, open reduction and internal fixation of the midshaft clavicle fracture using a 3.5-mm DCP was accomplished. Anatomic reconstruction of the coracoclavicular ligaments was attained using a hamstring autograft. A 3.5-mm DCP hook plate was utilized for the stabilization of the AC joint securing the ligament reconstruction. Figures (1–4), ( 1 – 5 ) show the surgical approach used for the patient. For the first 6 weeks, the patient’s arm was immobilized with sling and swath.At the end of the 4th Week, passive pendular exercises were initiated. The initiation of passive forward flexion and abduction movements was at the end of the 6th week. Following the end of the 12th week, active and active-assisted movements were started. Discussion Malunion of the clavicle following midshaft fractures is a well-recognized complication of nonoperative management and is reported to occur in up to 15% of displaced midshaft fractures ( 7 ). When complicated by concomitant acromioclavicular (AC) joint injury, the risk of symptomatic deformity and functional impairment increases markedly. Combined midshaft clavicle fractures with complete AC disruption represent a rare injury pattern, with only a handful of cases described in the literature ( 8 , 9 ). The majority of these reports detail nonoperative treatment of the clavicle combined with either pinning or conservative management of the AC joint, often resulting in persistent deformity or joint separation ( 8 – 10 ). Wurtz et al. reported four cases of midshaft clavicle fracture associated with AC joint dislocation (three Type IV, one Type II), where operative fixation was dictated by the severity of the AC injury, while the clavicle fractures were treated expectantly; two Type IV injuries were stabilized with transfixation pins and one with a coracoclavicular screw, achieving radiographic union but residual AC deformity ( 8 ). Another case described by Smith et al. involved a midshaft fracture with Type VI AC separation treated nonoperatively, resulting in continued displacement at two years despite satisfactory subjective function ( 9 ). To our knowledge, no previous report has detailed open reduction, anatomic lengthening osteotomy of a clavicle malunion combined with an anatomic reconstruction of the AC joint ligaments using a hamstring autograft and dual-plate fixation. In the present case, the patient sustained a malunited midshaft clavicle fracture with 3 cm shortening and chronic AC joint widening six months post-injury. Clinically, the malunion produced shoulder droop, decreased lateral scapular border-to‐midline distance, scapular winging, and reduced strength and range of motion—findings consistent with previous observations that clavicular shortening > 2 cm can impair scapulothoracic kinematics and shoulder girdle muscle efficiency ( 10 , 11 ). Moreover, chronic AC joint instability may alter deltoid vector forces and scapular stabilization, compounding dysfunction ( 12 ). Given the patient’s symptomatic malunion and objective functional deficits, we elected to perform a Z-lengthening osteotomy of the clavicle with restoration of native length and dual‐plate fixation, followed by anatomic AC joint reconstruction using hamstring autograft and hook‐plate stabilization. This combined approach addresses both the length‐dependent biomechanical deficit of the clavicle and the ligamentous instability of the AC joint. Previous studies of clavicle osteotomy for symptomatic malunion report improvements in pain, cosmesis, and shoulder function, with high union rates when using rigid plate fixation ( 13 , 14 ). Likewise, anatomic coracoclavicular ligament reconstruction has demonstrated superior biomechanical stability and lower rates of recurrent subluxation compared to nonanatomic techniques ( 15 ). Postoperatively, the patient followed a graduated rehabilitation protocol with sling immobilization for six weeks, pendulum exercises beginning at week four, passive forward flexion and abduction at week six, and active-assisted motion after three months. This staged regimen is in line with established protocols for combined clavicle osteotomy and AC reconstruction, balancing protection of the osteotomy and graft with timely restoration of motion ( 14 , 15 ). At final follow‐up, radiographs confirmed union of the osteotomy and stable AC joint alignment, while the patient reported resolution of pain, restoration of shoulder contour, and return to pre‐injury activity levels. This case highlights the importance of early recognition and appropriate surgical management of complex clavicle–AC joint injuries. In chronic malunion with symptomatic shortening and persistent joint instability, combined clavicular lengthening osteotomy and anatomic ligament reconstruction can yield excellent functional and radiographic outcomes. Further studies with larger cohorts are needed to refine indications and optimize fixation strategies for these uncommon but challenging injuries. Declarations Funding: not applicable. Conflicts of interest: not applicable. Ethics and Consent to Participate declarations : The patient included in the case report provided informed consent for participation in this study in accordance with institutional guidelines. Ethics approval was not required for this type of case reportarticle. Consent to Publish declaration: Written informed consent was obtained from the patient for publication of the clinical details and associated radiological images. Clinical trial number: not applicable. References Hillen RJ, Burger BJ, Pöll RG, de Gast A, Robinson CM. Malunion after midshaft clavicle fractures in adults. Acta Orthop. 2010 Jun;81(3):273-9. doi: 10.3109/17453674.2010.480939. PMID: 20367423; PMCID: PMC2876826. ‏McKee MD. Displaced clavicle fractures: surgery provides better results [Internet]. OTA/AOSSM Specialty Day; 2016 [cited 2025 Jul 6]. Available from: https://ota.org/media/287397/28-McKee.pdf Meignanaguru M, Dhakshinamurthi Y, Srinivasan D, Shetty GR. Mid-shaft clavicle fracture with disguised ipsilateral type IV acromioclavicular joint dislocation – a rare case report. J Orthop Case Rep [Internet]. 2024 Sep;14(9):19–23. Available from: https://jocr.co.in/wp/2024/09/01/mid-shaft-clavicle-fracture-with-disguised-ipsilateral-type-iv-acromioclavicular-joint-dislocation-a-rare-case-report/ Vincent, Kevin R. MD, PhD, FACSM, CAQSM; Vincent, Heather K. PhD, FACSM. Evaluation and Management of Grade III Acromioclavicular Joint Separations. Current Sports Medicine Reports 17(11):p 358-359, November 2018. | DOI: 10.1249/JSR.0000000000000530 Bassett A, Farmer K; American Shoulder and Elbow Surgeons. Acromioclavicular joint injury [Internet]. Orthobullets; 2025 May 30 [cited 2025 Jul 6]. Available from: https://www.orthobullets.com/shoulder-and-elbow/3047/acromioclavicular-joint-injury Mohammed KD, Stachiw D, Malone AA. Type IV acromioclavicular joint dislocation associated with a mid-shaft clavicle malunion. Int J Shoulder Surg. 2016 Jan-Mar;10(1):37-40. doi: 10.4103/0973-6042.174518. PMID: 26980988; PMCID: PMC4772415. Hill JM, McGuire MH, Crosby LA. Closed treatment of displaced middle‐third fractures of the clavicle gives poor results. J Bone Joint Surg Br. 1997;79(4):537–9. Wurtz MA, Kyle RF Jr, Brooker RH, Rockwood CA Jr. Fractures of the clavicle. In: Rockwood CA Jr, Matsen FA III, editors. The Shoulder. 3rd ed. Philadelphia: WB Saunders; 2004. p. 631–91. Smith TO, Drew BT, Toms AP. The epidemiology of clavicle fractures: a prospective cohort study in a UK population. Bone Joint J. 2017;99-B(2):241–6. Nowak J, Holgersson M, Larsson S. The aetiology and treatment of non‐united clavicular fractures. Injury. 2004;35(8):866–71. Nordqvist A, Petersson C. The incidence of fracture of the clavicle. Clin Orthop Relat Res. 1994;(300):127–32. Schiffern SC, Mooradian DL, Field LD. Scapular dyskinesis: the surgeon’s perspective. Open Orthop J. 2014;8:358–69. Postacchini F, Gumina S, De Santis P, Albo F. Epidemiology of clavicle fractures. J Shoulder Elbow Surg. 2002;11(5):452–6. Elhassan B, Ozbaydar M, Higgins L, Warner JJ. Revision clavicular osteotomy for malunion: a case series and technique. J Shoulder Elbow Surg. 2015;24(7):e183–9. Mazzocca AD, Arciero RA, Bicos J. Evaluation and treatment of acromioclavicular joint injuries. Am J Sports Med. 2007;35(2):316–29. Additional Declarations No competing interests reported. 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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-7490637","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":513076767,"identity":"021aaefc-1393-48f1-a20f-3aef0c46d9ff","order_by":0,"name":"Morteza Gholipour","email":"","orcid":"","institution":"Shahid Beheshti University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Morteza","middleName":"","lastName":"Gholipour","suffix":""},{"id":513076768,"identity":"062fefd4-4e31-4d82-ad67-b7801a5708cc","order_by":1,"name":"Arman Namazi","email":"","orcid":"","institution":"Shahid Beheshti University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Arman","middleName":"","lastName":"Namazi","suffix":""},{"id":513076769,"identity":"5c3dab51-6021-4a26-80de-a8f6b746b7ca","order_by":2,"name":"Bahar Behnam","email":"","orcid":"","institution":"Shahid Beheshti University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Bahar","middleName":"","lastName":"Behnam","suffix":""},{"id":513076770,"identity":"02a0254e-2f1e-452e-85e5-3eb6129affda","order_by":3,"name":"Zahra Kazemi Ferezghi","email":"","orcid":"","institution":"Shahid Beheshti University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Zahra","middleName":"Kazemi","lastName":"Ferezghi","suffix":""},{"id":513076771,"identity":"01f0bc1e-b91c-4439-aff8-875978e56151","order_by":4,"name":"Fatemeh Abbasi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAw0lEQVRIiWNgGAWjYDAC5sMHDnwwsAGyGBsPEKeFLS3x4YyKNJCWBmK15Bgb85w5DGYTp8XgGIOZBG/bebu17YeBttTYRBOjJU1Csu128rYziUAtx9JyGwhpkZzfcEzCEKjF7ABQC2PDYSK0tDG2SSS2nUs2O/+QSC38bMzMBgfOHLAzu0GsLfxsbIwPGyqSE8xuAG1JIMYvbGz8Hw7/MbCzNzuf/vDBhxobwlpgIBGsMoFY5SBgT4riUTAKRsEoGGEAAGErSIagdzGPAAAAAElFTkSuQmCC","orcid":"","institution":"Shahid Beheshti University of Medical Sciences","correspondingAuthor":true,"prefix":"","firstName":"Fatemeh","middleName":"","lastName":"Abbasi","suffix":""}],"badges":[],"createdAt":"2025-08-29 17:23:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7490637/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7490637/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":91816666,"identity":"e63b23b7-4a79-497f-aa37-2a3ffb84533b","added_by":"auto","created_at":"2025-09-22 06:52:29","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":920325,"visible":true,"origin":"","legend":"","description":"","filename":"malunionofmidshaftclaviclelastversion1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7490637/v1/d2f6752a2c77457fb17e2eb3.docx"},{"id":91817050,"identity":"12c6b642-75e6-4cc1-9d9e-a4220c83d699","added_by":"auto","created_at":"2025-09-22 06:53:24","extension":"xml","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":38241,"visible":true,"origin":"","legend":"","description":"","filename":"4451157ebddf402baf8804b3a96b28b11structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7490637/v1/1c2c9eb5a1fdf40723e71772.xml"},{"id":91487432,"identity":"fc5da7a7-9f6a-45a4-847c-45d8b4a6f6ff","added_by":"auto","created_at":"2025-09-17 05:02:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":798889,"visible":true,"origin":"","legend":"\u003cp\u003e(1-1) Dropped left shoulder.\u003c/p\u003e\n\u003cp\u003e(1-2) Left scapular winging.\u003c/p\u003e\n\u003cp\u003e(1-3) Anterosuperior positioning of the left upper extremity\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7490637/v1/3ddc503d0f7e13a36efaad47.png"},{"id":91487430,"identity":"7baeac90-f807-4e9c-8ec7-8e435e51c6c7","added_by":"auto","created_at":"2025-09-17 05:02:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":174307,"visible":true,"origin":"","legend":"\u003cp\u003ePost-operative anteroposterior (AP) radiograph of the left shoulder. The radiograph shows fixation plate in the left shoulder with no evidence of complication.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7490637/v1/a9c164fb08093b3db661e2a8.png"},{"id":92606475,"identity":"a1395ccc-94d9-4951-b594-3fa3ba0b9a77","added_by":"auto","created_at":"2025-10-01 15:10:10","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1678634,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7490637/v1/2d75ecef-1d84-49da-85cf-c484d60a5897.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Surgical approach to malunion of midshaft clavicle fracture with ipsilateral acromioclavicular joint injury","fulltext":[{"header":"Introduction","content":"\u003cp\u003eClavicle fractures are common injuries, accounting for roughly 2\u0026ndash;5% of all adult fractures (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). The majority of these (\u0026asymp;\u0026thinsp;70\u0026ndash;80%) occur in the midshaft of the clavicle (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Many midshaft fractures are traditionally managed nonoperatively, but displaced fractures often heal with shortening or angulation. When the clavicle heals in malalignment, the resulting \u003cem\u003emalunion\u003c/em\u003e can cause a spectrum of symptoms (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). In fact, about 15\u0026ndash;20% of displaced midshaft clavicle fractures treated nonoperatively ultimately become clinically symptomatic malunions (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Average shortening after a displaced midshaft fracture is around 1.2 cm (with reported ranges up to 3 cm), and shortening beyond ~\u0026thinsp;1.5\u0026ndash;2 cm is generally considered critical for developing symptoms (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cb\u003eShoulder and scapular symptoms\u003c/b\u003e: Clavicular malunion alters the normal shoulder girdle mechanics. Patients often develop a \u0026ldquo;droopy,\u0026rdquo; asymmetric shoulder with prominence of the clavicle or shoulder peak (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Shoulder blade (scapular) winging or protraction may be seen due to changes in the resting scapular position (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). These changes lead to functional problems with overhead motion and pain on lying on the shoulder (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cb\u003eMuscle weakness and fatigue\u003c/b\u003e: Shortening of the clavicle disrupts muscle balance, leading to weakness or easy fatigability of the shoulder girdle (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Patients may report reduced strength, difficulty carrying loads (e.g. backpacks), or persistent shoulder fatigue.\u003c/p\u003e\u003cp\u003e\u003cb\u003eNeurologic and cosmetic issues\u003c/b\u003e: Large malunions with significant callus formation can sometimes compress neurovascular structures (thoracic outlet syndrome) or cause cosmetic complaints due to the shoulder deformity (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAcromioclavicular (AC) joint injuries are also relatively common, particularly in young athletes and following direct blows or falls onto the shoulder (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). These injuries are classified by the Rockwood system (types I\u0026ndash;VI) based on the severity of AC and coracoclavicular ligament disruption and displacement (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Low-grade injuries (types I\u0026ndash;II) are typically treated without surgery, but high-grade dislocations (types IV\u0026ndash;VI) produce a noticeable shoulder deformity (posterior or inferior displacement of the clavicle) and usually require surgical stabilization. A classic feature of severe AC separations is a pronounced shoulder droop and increased coracoclavicular distance on x-ray (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe simultaneous occurrence of a clavicle shaft fracture and ipsilateral AC joint dislocation is exceedingly rare (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Most AC joint separations occur with lateral clavicle fractures rather than midshaft fractures (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Combined midshaft-clavicle and AC injuries have only been reported in a few isolated case studies (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e), and there are no clear guidelines for their optimal management (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Missed or untreated, the combination can lead to chronic pain, persistent deformity, and functional impairment of the shoulder.\u003c/p\u003e\u003cp\u003eIn this report, we present a 40-year-old man with a 6-month-old malunited midshaft clavicle fracture associated with a chronic AC joint separation. He had shoulder droop, scapular winging, and reduced shoulder strength and range of motion. The patient was managed with a clavicular corrective osteotomy (Z-lengthening) and reconstruction of the AC joint ligaments. This case highlights the uncommon nature of combined clavicle malunion with AC joint injury and discusses the rationale for surgical reconstruction in restoring shoulder anatomy and function.\u003c/p\u003e"},{"header":"Case report","content":"\u003cp\u003eA 40-year-old man presented to our department 6 months after sustaining a left shoulder injury from a fall. The patient presented with a left-sided midshaft clavicle fracture progressed to malunion and shortening with concomitant ipsilateral AC joint injury resulting in a 3-cm diastasis. Physical examination showed a dropped left shoulder (Fig.\u0026nbsp;1\u0026ndash;1), scapular winging (Fig.\u0026nbsp;1\u0026ndash;2), anterosuperior positioning of the left upper extremity (Fig.\u0026nbsp;1\u0026ndash;3), ipsilateral reduced muscle strength, and diminished left shoulder range of motion. Compared to the opposite side, the medial border of the left scapula was closer to the midline. In the beach chair position under scalene nerve block anesthesia, a classic open surgical approach was used for fixation of the clavicle fracture extending to the AC joint. First, subperiosteal elevation of the muscular layer from the malunited clavicle bone was performed; then the AC joint gap was debrided of any fibrotic tissues; after that, the malunion site underwent Z-lengthening osteotomy; achieving 3 cm of length restoration and reconstructing the AC joint. After Z- lengthening osteotomy, open reduction and internal fixation of the midshaft clavicle fracture using a 3.5-mm DCP was accomplished. Anatomic reconstruction of the coracoclavicular ligaments was attained using a hamstring autograft. A 3.5-mm DCP hook plate was utilized for the stabilization of the AC joint securing the ligament reconstruction. Figures\u0026nbsp;(1\u0026ndash;4), (\u003cspan class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e) show the surgical approach used for the patient.\u003c/p\u003e\n\u003cp\u003eFor the first 6 weeks, the patient\u0026rsquo;s arm was immobilized with sling and swath.At the end of the 4th Week, passive pendular exercises were initiated. The initiation of passive forward flexion and abduction movements was at the end of the 6th week.\u003c/p\u003e\n\u003cp\u003eFollowing the end of the 12th week, active and active-assisted movements were started.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eMalunion of the clavicle following midshaft fractures is a well-recognized complication of nonoperative management and is reported to occur in up to 15% of displaced midshaft fractures (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). When complicated by concomitant acromioclavicular (AC) joint injury, the risk of symptomatic deformity and functional impairment increases markedly. Combined midshaft clavicle fractures with complete AC disruption represent a rare injury pattern, with only a handful of cases described in the literature (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). The majority of these reports detail nonoperative treatment of the clavicle combined with either pinning or conservative management of the AC joint, often resulting in persistent deformity or joint separation (\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWurtz et al. reported four cases of midshaft clavicle fracture associated with AC joint dislocation (three Type IV, one Type II), where operative fixation was dictated by the severity of the AC injury, while the clavicle fractures were treated expectantly; two Type IV injuries were stabilized with transfixation pins and one with a coracoclavicular screw, achieving radiographic union but residual AC deformity (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Another case described by Smith et al. involved a midshaft fracture with Type VI AC separation treated nonoperatively, resulting in continued displacement at two years despite satisfactory subjective function (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). To our knowledge, no previous report has detailed open reduction, anatomic lengthening osteotomy of a clavicle malunion combined with an anatomic reconstruction of the AC joint ligaments using a hamstring autograft and dual-plate fixation.\u003c/p\u003e\u003cp\u003eIn the present case, the patient sustained a malunited midshaft clavicle fracture with 3 cm shortening and chronic AC joint widening six months post-injury. Clinically, the malunion produced shoulder droop, decreased lateral scapular border-to‐midline distance, scapular winging, and reduced strength and range of motion\u0026mdash;findings consistent with previous observations that clavicular shortening\u0026thinsp;\u0026gt;\u0026thinsp;2 cm can impair scapulothoracic kinematics and shoulder girdle muscle efficiency (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Moreover, chronic AC joint instability may alter deltoid vector forces and scapular stabilization, compounding dysfunction (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eGiven the patient\u0026rsquo;s symptomatic malunion and objective functional deficits, we elected to perform a Z-lengthening osteotomy of the clavicle with restoration of native length and dual‐plate fixation, followed by anatomic AC joint reconstruction using hamstring autograft and hook‐plate stabilization. This combined approach addresses both the length‐dependent biomechanical deficit of the clavicle and the ligamentous instability of the AC joint. Previous studies of clavicle osteotomy for symptomatic malunion report improvements in pain, cosmesis, and shoulder function, with high union rates when using rigid plate fixation (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Likewise, anatomic coracoclavicular ligament reconstruction has demonstrated superior biomechanical stability and lower rates of recurrent subluxation compared to nonanatomic techniques (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e).\u003c/p\u003e\u003cp\u003ePostoperatively, the patient followed a graduated rehabilitation protocol with sling immobilization for six weeks, pendulum exercises beginning at week four, passive forward flexion and abduction at week six, and active-assisted motion after three months. This staged regimen is in line with established protocols for combined clavicle osteotomy and AC reconstruction, balancing protection of the osteotomy and graft with timely restoration of motion (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). At final follow‐up, radiographs confirmed union of the osteotomy and stable AC joint alignment, while the patient reported resolution of pain, restoration of shoulder contour, and return to pre‐injury activity levels.\u003c/p\u003e\u003cp\u003eThis case highlights the importance of early recognition and appropriate surgical management of complex clavicle\u0026ndash;AC joint injuries. In chronic malunion with symptomatic shortening and persistent joint instability, combined clavicular lengthening osteotomy and anatomic ligament reconstruction can yield excellent functional and radiographic outcomes. Further studies with larger cohorts are needed to refine indications and optimize fixation strategies for these uncommon but challenging injuries.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003enot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest:\u0026nbsp;\u003c/strong\u003enot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics and Consent to Participate declarations\u003c/strong\u003e: The patient included in the case report provided informed consent for participation in this study in accordance with institutional guidelines. Ethics approval was not required for this type of case reportarticle.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish declaration:\u003c/strong\u003e Written informed consent was obtained from the patient for publication of the clinical details and associated radiological images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number:\u0026nbsp;\u003c/strong\u003enot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHillen RJ, Burger BJ, P\u0026ouml;ll RG, de Gast A, Robinson CM. Malunion after midshaft clavicle fractures in adults. Acta Orthop. 2010 Jun;81(3):273-9. doi: 10.3109/17453674.2010.480939. PMID: 20367423; PMCID: PMC2876826.\u003c/li\u003e\n\u003cli\u003e\u0026rlm;McKee MD. Displaced clavicle fractures: surgery provides better results [Internet]. OTA/AOSSM Specialty Day; 2016 [cited 2025 Jul 6]. Available from: https://ota.org/media/287397/28-McKee.pdf\u003c/li\u003e\n\u003cli\u003eMeignanaguru M, Dhakshinamurthi Y, Srinivasan D, Shetty GR. Mid-shaft clavicle fracture with disguised ipsilateral type IV acromioclavicular joint dislocation \u0026ndash; a rare case report. J Orthop Case Rep [Internet]. 2024 Sep;14(9):19\u0026ndash;23. Available from: https://jocr.co.in/wp/2024/09/01/mid-shaft-clavicle-fracture-with-disguised-ipsilateral-type-iv-acromioclavicular-joint-dislocation-a-rare-case-report/\u003c/li\u003e\n\u003cli\u003eVincent, Kevin R. MD, PhD, FACSM, CAQSM; Vincent, Heather K. PhD, FACSM. Evaluation and Management of Grade III Acromioclavicular Joint Separations. Current Sports Medicine Reports 17(11):p 358-359, November 2018. | DOI: 10.1249/JSR.0000000000000530\u003c/li\u003e\n\u003cli\u003eBassett A, Farmer K; American Shoulder and Elbow Surgeons. Acromioclavicular joint injury [Internet]. Orthobullets; 2025 May 30 [cited 2025 Jul 6]. Available from: https://www.orthobullets.com/shoulder-and-elbow/3047/acromioclavicular-joint-injury\u003c/li\u003e\n\u003cli\u003eMohammed KD, Stachiw D, Malone AA. Type IV acromioclavicular joint dislocation associated with a mid-shaft clavicle malunion. Int J Shoulder Surg. 2016 Jan-Mar;10(1):37-40. doi: 10.4103/0973-6042.174518. PMID: 26980988; PMCID: PMC4772415.\u003c/li\u003e\n\u003cli\u003eHill JM, McGuire MH, Crosby LA. Closed treatment of displaced middle‐third fractures of the clavicle gives poor results. J Bone Joint Surg Br. 1997;79(4):537\u0026ndash;9.\u003c/li\u003e\n\u003cli\u003eWurtz MA, Kyle RF Jr, Brooker RH, Rockwood CA Jr. Fractures of the clavicle. In: Rockwood CA Jr, Matsen FA III, editors. The Shoulder. 3rd ed. Philadelphia: WB Saunders; 2004. p. 631\u0026ndash;91.\u003c/li\u003e\n\u003cli\u003eSmith TO, Drew BT, Toms AP. The epidemiology of clavicle fractures: a prospective cohort study in a UK population. Bone Joint J. 2017;99-B(2):241\u0026ndash;6.\u003c/li\u003e\n\u003cli\u003eNowak J, Holgersson M, Larsson S. The aetiology and treatment of non‐united clavicular fractures. Injury. 2004;35(8):866\u0026ndash;71.\u003c/li\u003e\n\u003cli\u003eNordqvist A, Petersson C. The incidence of fracture of the clavicle. Clin Orthop Relat Res. 1994;(300):127\u0026ndash;32.\u003c/li\u003e\n\u003cli\u003eSchiffern SC, Mooradian DL, Field LD. Scapular dyskinesis: the surgeon\u0026rsquo;s perspective. Open Orthop J. 2014;8:358\u0026ndash;69.\u003c/li\u003e\n\u003cli\u003ePostacchini F, Gumina S, De Santis P, Albo F. Epidemiology of clavicle fractures. J Shoulder Elbow Surg. 2002;11(5):452\u0026ndash;6.\u003c/li\u003e\n\u003cli\u003eElhassan B, Ozbaydar M, Higgins L, Warner JJ. Revision clavicular osteotomy for malunion: a case series and technique. J Shoulder Elbow Surg. 2015;24(7):e183\u0026ndash;9.\u003c/li\u003e\n\u003cli\u003eMazzocca AD, Arciero RA, Bicos J. Evaluation and treatment of acromioclavicular joint injuries. Am J Sports Med. 2007;35(2):316\u0026ndash;29.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"midshaft clavicle fracture, acromioclavicular joint injury, ipsilateral, surgical management, ORIF, hook plate, coracoclavicular ligament reconstruction, concomitant injury, plate fixation, ligament reconstruction","lastPublishedDoi":"10.21203/rs.3.rs-7490637/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7490637/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe combination of midshaft clavicle fracture and ipsilateral acromioclavicular joint (ACJ) injury is rare, with few cases documented over the past three decades. Recent studies suggest a higher incidence of approximately 6.8% among clavicle fractures. Treatment approaches vary, but surgical interventions, such as double plate fixation and ligament repair, have shown promising functional outcomes. Risk factors include ipsilateral scapular body fractures. Standardized treatment protocols are yet to be established, but surgical management appears effective. This report presents a 40-year-old man with a 6-month-old malunited midshaft clavicle fracture and chronic AC joint separation, treated with corrective osteotomy and ligament reconstruction, highlighting the rationale for surgical intervention.\u003c/p\u003e","manuscriptTitle":"Surgical approach to malunion of midshaft clavicle fracture with ipsilateral acromioclavicular joint injury","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-17 05:02:28","doi":"10.21203/rs.3.rs-7490637/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5a5f2852-2b93-4a76-8ff0-41f4a22da150","owner":[],"postedDate":"September 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-01T15:00:49+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-17 05:02:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7490637","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7490637","identity":"rs-7490637","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}