Double-Screw Osteosynthesis in an Unstable Scaphoid Fracture Model: A Biomechanical Comparison of Two Screw Configurations.

PURPOSE: Although there is evidence that a single headless compression screw is sufficient for fixation of most scaphoid fractures, double-screw osteosynthesis has been shown to result in higher failure strength and stiffness than a single screw. However, the biomechanical effect of different screw configurations has not been determined. METHODS: A standardized unstable fracture model was produced in 28 cadaveric scaphoids. Specimens were randomly allocated to 1 of 2 fixation groups using 2 internal compression screws positioned in either the sagittal or coronal plane. A specimen-specific 3-dimensionally-printed customized screw placement and osteotomy device was developed using computer-aided design-generated models derived from computed tomography scan data of each individual scaphoid. Load to failure and stiffness of the repair constructs were evaluated using a mechanical testing system. RESULTS: There were no significant differences in size, weight, and density between the scaphoid specimens. The average distance between screws was significantly greater in the sagittal group than in the coronal group. There were no significant differences between the coronal and sagittal aligned double screws in load to 2 mm displacement (mean coronal 180.9 ± 109.7 N; mean sagittal 156.0 ± 85.8 N), load to failure (mean coronal 275.9 ± 150.6 N; mean sagittal 248.0 ± 109.5 N), stiffness (mean coronal 111.7 ± 67.3 N/mm; mean sagittal 101.2 ± 45.1 N/mm), and energy absorption (mean coronal 472.6 ± 261.4 mJ; mean sagittal 443.5 ± 272.7 mJ). CONCLUSIONS: There are no significant biomechanical differences between the sagittal or coronal aligned double headless compression screws in a scaphoid fracture model with bone loss. CLINICAL RELEVANCE: In cases where double-screw fixation of the scaphoid is being considered, the placement of double screws can be at the discretion of the surgeon, and can be dictated by ease of access, surgical preference, and fracture orientation.

Measurement of Scaphoid Bone Microarchitecture: A Computed Tomography Imaging Study and Implications for Screw Placement.

PURPOSE: High bone density and quality is associated with improved screw fixation in fracture fixation. The objective of this study was to assess bone density and quality in the proximal and distal scaphoid to determine optimum sites for placement of 2 screws in scaphoid fracture fixation. METHODS: Twenty-nine cadaveric human scaphoid specimens were harvested and scanned using micro-computed tomography. Bone density (bone volume fraction) and bone quality (relative bone surface area, trabecular number, and trabecular thickness) were evaluated in 4 quadrants within each of the proximal and distal scaphoid. RESULTS: The proximal radial quadrant of the scaphoid had significantly greater bone volume than the distal ulnar (mean difference, 33.2%) and distal volar quadrants (mean difference, 32.3%). There was a significantly greater trabecular number in the proximal radial quadrant than in the distal ulnar (mean difference, 16.7%) and in the distal volar quadrants (mean difference, 15.9%) and between the proximal ulnar and the distal ulnar quadrants (mean difference, 12%). There was a significantly greater bone surface area in the proximal radial and distal radial quadrants than in the distal ulnar and distal volar quadrants. There were no significant differences in trabecular thickness between the 8 analyzed quadrants CONCLUSIONS: Although there are differences in bone volume, trabecular number, and bone surface area between the proximal pole of the scaphoid and that of the distal pole, there were no significant differences in the bone quality (trabecular thickness, trabecular number, and relative bone surface area) and density (bone volume fraction) between the 4 quadrants of the proximal or distal pole of the cadaveric scaphoids studied. CLINICAL RELEVANCE: Insertion of 2 headless compression screws can be determined by ease of surgical access and ease of screw positioning and not by differences in bone quality or density of the proximal or distal scaphoid.

Fixation of the Fractured Lunate in Kienböck Disease.

PURPOSE: To describe an uncommon subset of fractured lunates in Kienböck disease that is salvageable by internal fixation. METHODS: We performed a retrospective review for patients with Kienböck disease treated by internal fixation. Demographic data, objective and radiographic measurements, patient-reported outcome measures (Disabilities of the Arm, Shoulder, and Hand and Patient-Rated Wrist Evaluation) and pain (visual analog scale) scores were collected. RESULTS: Of the 7 patients treated, 5 were available for review. At an average follow-up of 7.1 years (range, 1.5-15 years), all patients had activity-related wrist pain but were pain-free at rest. Radiographic assessment showed union in all lunates and a normal radioscaphoid angle and Stahl index. The modified carpal height ratio was reduced in 4 patients and normal in one. There was no observed narrowing or irregularity of the radiocarpal or midcarpal joints. Patient-reported outcome measures in 2 patients were unsatisfactory. CONCLUSIONS: Computed tomography of the lunate in Kienböck disease is an important investigative tool. A coronal split fracture of these lunates can be salvageable by internal fixation. Revascularization of the lunate can be performed when the fragment is of sufficient size. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Propionibacterium Acnes Infection of a Metacarpophalangeal Joint Arthroplasty.

Neglected and underestimated in the past, Propionibacterium acnes is currently the most prevalent organism associated with deep prosthetic infections around the shoulder. Surprisingly, it has never been reported as a cause of infection in the hand. Here we report a case of a late presentation of a P. acnes infection in a metacarpophalangeal joint replacement, resulting in chronic low-grade pain with movement. The patient underwent a 2-stage revision, with initial removal of the prosthesis. Positive cultures for P. acnes required 15 days of extended incubation. The patient subsequently had 6 weeks of oral antibiotics followed by a second-stage revision with a Silastic implant.

Outcomes after operative treatment of elbow contractures in the pediatric and adolescent population.

BACKGROUND: The role of elbow contracture release in the very young is unclear, with existing studies reporting conflicting results. This study evaluated the long-term results after open elbow contracture release in patients aged younger than 18 years. METHODS: Between 1994 and 2012, 32 patients underwent open elbow contracture release at a mean age of 13.8 years (range, 5-18 years), and their outcomes were reviewed. The primary cause was traumatic in 30 patients (4 radial head/neck fractures, 5 intra-articular distal humeral fractures, 11 extra-articular distal humeral fractures, 10 complex fracture-dislocations), and the mean time from the index injury to contracture release was 16.3 months (range, 3-82 months). The cause in 2 patients was nontraumatic (1 osteochondritis dessicans, 1 congenital). The mean follow-up period was 66 months (range, 7-202 months). RESULTS: At the latest follow-up, total arc of motion improved from 69° to 123° (P <.0001), with a mean increase of 54° (P <.0001). The function arc was >100° in 28 patients (88%), and 29 patients (91%) achieved >20° of improvement in their arc. Twelve patients (38%) underwent a gentle manipulation under anesthesia at a mean of 2.7 weeks (range, 1-5 weeks) for early recurrence of stiffness. There were 3 complications (1 deep infection, 1 hematoma, 1 humeral fracture through the external fixator pin site). No patients lost motion after surgery. CONCLUSION: Elbow contracture release in the pediatric and adolescent population can provide significant improvements in range of motion similar to that achieved in adults. The improvements in motion are durable.

Surgical treatment of isolated type II superior labrum anterior-posterior (SLAP) lesions: repair versus biceps tenodesis.

BACKGROUND: It is still unclear which patients with isolated type II superior labrum anterior-posterior (SLAP) lesions benefit from either superior labral repair or biceps tenodesis. This study evaluates the indications and outcomes of patients with isolated type II SLAP lesions who have undergone either procedure. METHODS: A retrospective analysis was performed of patients who had surgery for an isolated type II SLAP lesion between 2008 and 2011. There were 25 patients: 15 underwent biceps tenodesis, with a mean follow-up of 31 months (range, 26-43 months), and 10 underwent SLAP repair, with a mean follow-up of 35 months (range, 25-52 months). The mean age was 47 years (range, 30-59 years) in the tenodesis group and 31 years (range, 21-43 years) in the repair group. RESULTS: At latest follow-up, both groups showed significant improvements in subjective shoulder value and pain score. No difference was observed in American Shoulder and Elbow Surgeons score (93.0 vs 93.5, P = .45), patient satisfaction (93% vs 90%, P = .45), or return to preinjury sporting level (73% vs 60%, P = .66). Analysis of the indications for treatment showed that in the large majority, tenodesis was performed in older patients (>35 years) and patients who showed degenerative or frayed labrums whereas SLAP repairs were performed in younger and more active patients with healthy-appearing labral tissue. There was only 1 failure in the tenodesis group, and in the SLAP repair group, there were 2 cases of postoperative stiffness; all were treated nonoperatively. CONCLUSION: In this study, we show that both biceps tenodesis and SLAP repair can provide good to excellent results if performed in appropriately selected patients with isolated type II SLAP lesions.

A Comparison of Rib Osteochondral Graft to Medial Femoral Trochlear Osteocartilaginous Graft for the Salvage of the Fragmented Scaphoid Proximal Pole: A Single-Center Experience with Minimum 2-Year Follow-Up.

Purpose Fragmented fractures of the proximal pole of the scaphoid that cannot be internally fixed may be salvaged by four-corner arthrodesis or proximal row carpectomy. Replacement of the proximal scaphoid with costal-osteochondral graft (COG) or the medial femoral trochlea (MFT) graft are two alternative solutions for this clinical presentation. The purpose of this study was to compare the clinical and radiographic results of the COG and the MFT graft with a minimum 2-year follow-up from a single centre. Methods A retrospective study was performed to investigate the outcome of COG and MFT with a minimum 2 year follow up. Demographic data and clinical assessment including wrist range of motion and grip strength measurements and Oxford Knee score were collected. Patients completed the outcome measures of Disabilities of Arm, Shoulder, and Hand (DASH), the Patient-Rated Wrist Evaluation (PRWE), and a ten-point visual analogue score for pain (VAS). Radiological examination was performed on all wrists at follow-up. Results The visual analogue score, DASH and PRWE were similar between the two groups. There was radiographic evidence of arthritis between the radial styloid and distal scaphoid in all patients that underwent COG but no evidence in those that underwent MFT graft reconstruction. There were different complications in each group. Thirty percent of patients that underwent MFT reconstruction had persistent knee pain at follow up. Conclusion Though there are notable differences in the follow-up period, patients undergoing MFT risk developing knee pain, while those undergoing COG risk radiographic progression of wrist arthritis. Level of Evidence III - Comparative study.

A comparative analysis of fatty infiltration and muscle atrophy in patients with chronic rotator cuff tears and suprascapular neuropathy.

BACKGROUND: Little is known of the mechanisms that lead to the muscle changes associated with rotator cuff disorders. We have observed that the magnetic resonance imaging (MRI) appearance of fatty infiltration (FI) and muscle atrophy (MA) differ between chronic cuff tears and suprascapular neuropathy, suggesting different pathophysiology. This study compares the different MRI changes that occur in chronic cuff tears and suprascapular neuropathy. METHODS: Two groups were retrospectively identified: (1) RCT group (20 shoulders): patients with chronic tears of the supraspinatus and/or infraspinatus without electromyographic (EMG) evidence of suprascapular neuropathy; (2) neuro group (17 shoulders): patients with EMG documented suprascapular nerve dysfunction and absence of a rotator cuff tear. Magnetic resonance arthrograms were analyzed for the degree of FI and MA, and the morphology of the muscle was assessed, in particular the muscle border, pattern of FI, and extent of involvement. RESULTS: The muscle changes that occur following chronic cuff tears differ from that following denervation secondary to suprascapular neuropathy, especially with respect to the muscle border, degree of perineural fat, and overall distribution of FI. Highly specific and characteristic morphological patterns of FI exist for both chronic cuff tears and suprascapular neuropathy. CONCLUSION: Chronic rotator cuff tendon tears and suprascapular neuropathy are both associated with FI and MA of the rotator cuff muscles. The pattern of FI is markedly different in the 2 situations. These findings have diagnostic potential and may serve as a basis for further research concerning type, severity, and evolution of FI under different conditions and after treatment.

Accurate coracoid graft placement through use of a drill guide for the Latarjet procedure.

BACKGROUND: The Latarjet procedure has widely become the preferred treatment option for recurrent anterior glenohumeral instability in the presence of glenoid bone loss. The success of this procedure is largely dependent on accurate placement of the coracoid bone graft relative to the glenoid margin. With malpositioning of the coracoid graft, complications can arise, such as recurrent instability if placed too medially or impingement and subsequent early degenerative changes if positioned too laterally. To increase the accuracy and reproducibility of coracoid graft placement, we developed a simple and efficient drill guide that assists in accurate and safe positioning of the graft against the anterior glenoid to provide a congruent articular surface. MATERIALS AND METHODS: A new drill guide was used in 12 consecutive open Latarjet procedures. Accuracy of placement of the graft with respect to the anterior glenoid rim was assessed using postoperative computed tomography imaging. RESULTS: Accurate graft placement with a distance between the glenoid and the graft surface of less than 1 mm was obtained in all 12 interventions. The mean angulation of the screws relative to the glenoid face was 4.3° (range, 1°-7°). All screw heads were positioned medial to the articular edge of the graft, and the distance was always greater than 3 mm. CONCLUSIONS: The use of a simple drill guide allows safe and accurate graft placement during an open Latarjet procedure.

Reverse total shoulder arthroplasty for massive irreparable rotator cuff tears in patients younger than 65 years old: results after five to fifteen years.

BACKGROUND: The role of reverse shoulder arthroplasty (RTSA) in the relatively young individual is currently unclear. Our study evaluates the midterm to long-term results of RTSA for patients aged younger than 65 years with pseudoparalysis secondary to massive irreparable rotator cuff tears, with or without arthritis. METHODS: Between 1997 and 2006, 46 RTSAs (41 patients) were performed. Mean age was 60 years (range, 46-64 years). At the latest follow-up, 5 patients had died and 1 was lost, leaving 35 patients (40 shoulders) with a mean follow-up of 93 months (range, 60-171 months). RESULTS: The mean relative Constant score increased from 34% to 74% (P < .0001) and the subjective shoulder value improved from 23% to 66% (P < .0001). Significant improvements were seen in active forward elevation (72° to 119°), pain scores, and strength (P < .001). One or more complications occurred in 15 shoulders (37.5%), with 6 failures (15%) resulting in removal or conversion to hemiarthroplasty (3 with infection, 3 with glenoid loosening). Ten shoulders (25%) underwent partial or total component exchange, conversion to hemiarthroplasty, or removal. Of the 15 patients who developed complications, 9 did not require prosthesis removal or conversion and functional outcome and subjective shoulder value were similar to those with no complications (P > .4). CONCLUSION: RTSA in younger patients provides significant subjective improvement and substantial gain in overall function, which is maintained up to 10 years. Although the complication rate is high, most can be treated successfully without compromise to clinical outcome. However, it is imperative that the high complication rate is explained to patients, with the risks and benefits carefully considered.

Functional outcome of complex intercondylar fractures of the distal humerus treated through a triceps-sparing approach.

Complex intra-articular fractures of the distal humerus (AO/ASIF type C) pose a significant challenge to the treating surgeon. This study aimed to review the functional outcome of these fractures managed with open reduction and internal fixation through a posterior triceps-sparing approach. Nine cases were treated over a 7-year period, with 7 patients available for review. Of note, the majority of cases were accompanied with significant associated injuries, including vascular and soft tissue trauma. A retrospective analysis of a consecutive series, managed by a single surgeon, was conducted at a mean follow-up period of 35.1 months (range, 6-78). The mean age was 41 years (range, 12-73). At the time of review, all fractures had united and the median arc was 90 degrees (range, 70-115). All patients achieved good clinical scores as determined by the Mayo Clinic Performance Index. Quality of life assessment (SF-36) revealed no significant difference compared to the general population. The mean DASH score was 17.9, indicating mild residual impairment. There was no x-ray evidence of heterotopic ossification or post-traumatic osteoarthritis. The posterior triceps-sparing approach provides adequate exposure to the fracture site and allows early rehabilitation. Satisfactory functional outcome can be achieved for complex type C fractures of the distal humerus treated through this approach.

Inhibition of orthotopic osteosarcoma growth and metastasis by multitargeted antitumor activities of pigment epithelium-derived factor.

Osteosarcoma is major cause of cancer-related death in the pediatric age group, and this is due to the development of pulmonary metastases that fail to be eradicated with current treatment regimes. Although there have been significant improvements in the long-term survival of such patients, 25-50% with initially non-metastatic disease, subsequently develop metastases and this remains the major cause of death for these patients. In this study, we report the multimodal activity of pigment epithelium-derived factor (PEDF) in inhibiting osteosarcoma growth, angiogenesis and metastasis. In vitro, we found that administration of recombinant PEDF (rPEDF) on two osteosarcoma cell lines (rat UMR 106-01 and human SaOS-2) significantly reduced tumor cell proliferation and increased apoptosis, as well as decreased cell invasion, angiogenesis, and increased adhesion to collagen type-1. Administration of rPEDF upregulated the mRNA expression of phenotypic osteoblast differentiation markers (ALP, pro-alpha(1) collagen and osteocalcin) in a pre-osteoblastic cell line, UMR 201, and also increased mineralized nodule formation in both UMR 106-01 and SaOS-2. In vivo, rPEDF dramatically suppressed primary osteosarcoma growth and the development of macroscopic pulmonary metastases in an orthotopic model of human osteosarcoma (SaOS-2). Interestingly, no activity was seen in tumors grown subcutaneously, suggesting a paracrine interaction between PEDF and the bone microenvironment. Preliminary pharmacoevaluation studies demonstrated rPEDF stability within media containing serum and osteosarcoma cells, and no gross systemic toxicity was observed in vivo with rPEDF administration. These results suggest that PEDF is emerging as an attractive and clinically appealing drug candidate for the treatment of osteosarcoma.

PEDF: a potential molecular therapeutic target with multiple anti-cancer activities.

Pigment epithelium-derived factor (PEDF) is an endogenously produced protein that is widely expressed throughout the human body, and exhibits multiple and varied biological activities. Already established as a potent anti-angiogenic molecule, PEDF has recently shown promise as a potential anti-tumour agent, causing both direct and indirect tumour suppression. Here, we explore the unique anti-tumour properties of PEDF and discuss its role as an effective anti-angiogenic, anti-proliferative and pro-differentiation factor. We also discuss the prospects for PEDF therapy and the need for a closer evaluation of issues such as delivery, stability and potential toxicity.

Human xenograft osteosarcoma models with spontaneous metastasis in mice: clinical relevance and applicability for drug testing.

Osteosarcoma cells derived from patients have been isolated and subsequently cultured for the past 35 years. To date though, there have been no major breakthroughs in the development of a model for osteosarcoma that uses orthotopic implantation of human osteosarcoma cells and that closely emulates the clinical progression of this debilitating and fatal disease. Such a model is long overdue given the devastating demographics (second highest cause of cancer-related death in the paediatric age group) of the ailment and the lack of solid options for control, if not cure, for the disease, as it also is the most common primary tumour of bone. Only then can more robust R & D be undertaken in the search for efficacious anti-osteosarcoma agents. This review tackles this conundrum and lists the variety of models (that use human osteosarcoma cells) available and the types of studies performed with these.

Pigment epithelium-derived factor: a multimodal tumor inhibitor.

Pigment epithelium-derived factor (PEDF), a noninhibitory member of the serine protease inhibitor (serpin) family, is a well-known potent endogenous inhibitor of angiogenesis. It has been known for years to be aberrantly expressed in ocular disorders, but in recent years, down-regulation has been shown to be prevalent in a range of cancers as well. This review describes the trimodal anticancer activities of this interesting protein: antiangiogenesis, apoptosis-mediated tumor suppression, and tumor cell differentiation. The key to successful antitumor therapy with this protein is the ability to synthesize the recombinant form of the protein (or its active shortened forms) and deliver at therapeutic doses or alternatively to use gene transfer technology to prolong the effect in vivo. Although there is a substantial amount of work carried out at the preclinical stage with this protein, more groundwork has to be done before PEDF is tested against cancer in clinical trials.

Commonly used mouse models of osteosarcoma.

Osteosarcoma is the commonest primary tumour of bone and the second highest cause of cancer-related death in the paediatric age group. Little is known of the aetiology of human osteosarcoma and lesser still of the various interactions that occur between host and tumour cells that govern growth and progression of osteosarcoma in vivo. Although numerous osteosarcoma cell lines have been established and characterized in vitro, some as far back as in the 1960s, there is a scarcity of reliable and reproducible in vivo animal models that mimics all aspects of the human condition at the temporal, physiological and histopathological level, hence, making the accurate testing of therapeutic strategies difficult. Given that osteosarcoma is a disease that affects young people and better disease management strategies are essential, development of a robust human osteosarcoma model is long overdue.

Does the degree of intratumoural microvessel density and VEGF expression have prognostic significance in osteosarcoma?

The role of angiogenesis as a prognostic indicator in cancer has been extensively studied in recent times with several studies demonstrating a positive correlation for various malignant tumours. However, the role of angiogenesis in osteosarcoma remains a topic of debate. In this study, we aim to evaluate the significance of intratumoural microvessel density (MVD) and the degree of vascular epithelial growth factor (VEGF) expression as markers of angiogenesis and correlate this with disease outcome. Archival paraffin-embedded pre-treatment biopsy tissue of patients treated at St. Vincent's Hospital, Melbourne, with non-metastatic osteosarcoma at initial diagnosis was reviewed. Tissue was processed for immunofluorescent staining of the microvascular endothelial cells with antibodies directed against CD31 and CD34. The degree of angiogenesis was assessed, as determined by the microvessel density (MVD). Further histological examination was performed to assess the degree of VEGF expression. Histological observations were correlated with various clinicopathological factors and patient outcome in terms of recurrence, metastasis and death. Twenty-five cases were reviewed, 15 were male and 10 were female, and the median age was 26 years (range, 13-85). The mean follow-up was 21.5 months (range, 3-75 months). The median MVD was 43 microvessels/0.26 mm2 (range, 25-54) and 46 microvessels/0.26 mm2 (range, 30-58) for CD31 and CD34, respectively. Despite the moderate to high vascularity, there was no significant difference noted between the MVD and disease outcome factors for both CD31 and CD34. There was a trend towards a higher MVD in patients aged > 40 years compared to those < 40 years (p = 0.110 for CD31 and p = 0.097 for CD34). In terms of VEGF expression, 24 of 25 cases demonstrated either moderate or strong expression; however, no prognostic significance was determined. In this study, we were able to demonstrate that osteosarcoma is a relatively vascular tumour; however, the degree of MVD and VEGF expression does not provide prognostic information. It is likely that angiogenesis plays a key role in the pathogenesis of osteosarcoma and is, therefore, a potential target for novel anti-angiogenic therapies.

Outcome of patients with osteosarcoma over 40 years of age: is angiogenesis a marker of survival?

BACKGROUND: Osteosarcoma predominantly afflicts young people in their second and third decades of life. When osteosarcoma arises in patients older than 40 years, the prognosis is usually poorer compared to their younger counterparts. Although the clinical, histopathologic features and prognostic indicators are well defined for young patients, much less is known about affected adults. The purpose of this study is to describe our institution's experience with the management of osteosarcoma in patients greater than 40 years and also evaluate, by immunohistochemical analysis, the prognostic significance of microvessel density, as a marker of intratumoural angiogenesis. METHODS: A retrospective clinicopathological analysis was performed on 11 patients over the age of 40 years that were treated at our institution between 1996 and 2004. Archival pre-treatment biopsy tissue was retrieved for immunohistochemical staining against two endothelial cell markers (CD31 and CD34) and also against VEGF. Angiogenesis was assessed by determining the intratumoural microvessel density (MVD) and the degree of VEGF expression in these specimens. This was correlated with patient outcome in terms of local recurrence, metastasis and death. Histological results were also compared to a group of patients less than 40 years of age. RESULTS: Of the 11 patients, 9 were male and 2 were female and the mean age was 58 years (range, 42-85). In 7 patients, osteosarcoma arose secondarily from Paget's disease of the bone. The most common site involved was the humerus (7) followed by the femur (2) then pelvis (1) and ulna (1). At the time of diagnosis, 4 patients had metastatic disease. Preoperative chemotherapy was given to 4 patients, with a good response in 3 patients. Six patients underwent limb-sparing surgery, 4 had amputations and 1 was treated with radiotherapy alone. The mean follow up time was 31.5 months (range, 8-81). At this time, 4 patients (36%) had developed lung metastases and 5 patients (46%) had died. Overall survival was 54.5%. Intratumoural MVD was higher in patients over 40 years, although not statistically significant (p = 0.111, CD31; p = 0.134, CD34). VEGF was uniformly expressed in all sections, however no relationship was found between the degree of expression and patient age. CONCLUSION: The prognosis for older patients with osteosarcoma is generally poor. Initial presentation is commonly associated with metastatic disease and neoadjuvant chemotherapy is often avoided because of its side effects. Increased intratumoural vascularity may contribute to the poorer prognosis in these patients, however further studies are needed.

A Rare Case of Bipolar Clavicle Fracture.

Segmental or bipolar fractures of the clavicle generally refer to a concomitant ipsilateral distal clavicle and midshaft clavicle fracture. These injuries are exceedingly rare and are generally secondary to higher energy injuries. We report a case of a 38-year-old male who sustained a left bipolar clavicle fracture after falling from a push bike while riding recreationally which unusually involved the medial and lateral ends of the clavicle and not the midshaft as previously reported in other patients. The patient's exact fracture configuration was not immediately apparent highlighting the need for careful examination of the whole clavicle in order to not miss a bipolar fracture.