The influence of fracture location and comminution on acute scaphoid fracture displacement: three-dimensional CT analysis.

We aimed to assess the influence of fracture location and comminution on acute scaphoid fracture displacement using three-dimensional CT. CT scans of 51 adults with an acute scaphoid fracture were included. Three-dimensional CT was used to assess fracture location, comminution and displacement. Fracture location was expressed as the height of the cortical breach on the volar and dorsal side of the scaphoid relative to total scaphoid length (%), corresponding to the fracture's entry and exit point, respectively. We found a near-linear relation between dorsal fracture location and displacement. As dorsal fracture location became more distal, translation (ulnar, proximal, volar) and angulation (flexion, pronation) of the distal fragment relative to the proximal fragment increased. Comminuted fractures had more displacement. Dorsal fracture location predictably dictates the direction of translation and angulation in displaced scaphoid fractures. Surgeon attention to dorsal fracture location can help identify displacement patterns and provide guidance in adequately reducing a displaced scaphoid fracture.Level of evidence: III.

3D mapping of scaphoid fractures and comminution.

OBJECTIVE: Acute and subacute scaphoid fractures were assessed using 3D computer tomography (CT). The aims were to describe fracture morphology, to map fractures onto a 3D scaphoid model and to correlate this to scaphoid anatomy. MATERIALS AND METHODS: A retrospective, multicentre database search was performed to identify CT studies of acute and subacute scaphoid fractures. CT scans of scaphoid fractures less than 6 weeks from time of injury were included in this retrospective, multicentre study. CTs were segmented and converted into three-dimensional models. Following virtual fracture reduction, fractures were mapped onto a three-dimensional scaphoid model. RESULTS: Seventy-five CT scans were included. The median delay from injury to CT was 29 days. Most studies were in male patients (89%). Most fractures were comminuted (52%) or displaced (64%). A total of 73% of displaced fractures had concomitant comminution. Waist fractures had higher rates of comminution and displacement when compared with all other fractures. Comminution was located along the dorsal ridge and the volar scaphoid waist. CONCLUSION: Our study is the first to describe acute fracture morphology using 3D CT and to correlate comminution and displacement to fracture types. The dorsal ridge and volar waist need prudent assessment, especially in waist fractures.

A new radiographic view of the scaphotrapeziotrapezoid joint-a cadaveric study.

BACKGROUND: The scaphotrapeziotrapezoid joint (STTJ) has a complex osseous and ligamentous anatomy. Precise radiographic assessment is paramount when assessing osteoarthritic, post-traumatic, or post-operative patients. There has been no described technique to image the STTJ without any wrist movement, unobscured by the rest of the carpus. The aim of this study was to define an optimal radiographic method to assess the STTJ while maintaining the wrist in neutral position. METHODS: Computer tomography 3-D reconstructions of three uninjured wrists were initially used to determine an approximate beam angle. Serial radiographs of 12 cadaveric wrists were taken. The forearms were positioned in varying degrees of pronation and supination. The beam angle was concurrently adjusted to varying degrees of caudal tilt. From the images obtained, we assessed if the adjacent carpus obscured the view of the STTJ. RESULTS: Optimal STTJ imaging was in the semi-pronated wrist position with the X-ray beam tilted caudal. We found that the STTJ was best visualized at 48° supination from a fully pronated wrist and a caudal beam angle of 22°. CONCLUSIONS: The described wrist and beam orientation can aid in achieving an unobstructed view of the STTJ with little technical effort. This can aid in imaging ambulatory patients where symptoms prevent using other imaging techniques as well as patients in the operating room where imaging timing can be critical.

Hand infection patients presenting to an orthopaedic unit: An audit of incidence and demographics at a rural hospital.

OBJECTIVE: Hand infections are a common presentation to health services in the Northern Territory; however, little is known about these patients. This study aims to identify incidence, treatment and co-morbidities of hand infection patients and to pinpoint factors associated with poor outcome. DESIGN: A retrospective study of all patients presenting to Alice Springs Hospital with a hand infection during 2012. SETTING: Orthopaedic Unit at Alice Springs Hospital. PARTICIPANTS: All patients admitted with a hand infection were included. MAIN OUTCOME MEASURES: Admission duration, duration waited before first presentation, re-admission rate, duration of re-admission and rate of methicillin-resistant Staphylococcus aureus. RESULTS: One hundred fourteen cases of hand infections were admitted to Alice Springs Hospital during 2012, of which 87 (76%) were in Indigenous patients. Indigenous patients (P = 0.001) and older patients (P = 0.038) had significantly longer admissions. Indigenous patients were 9.52 times (P = 0.038) more likely to be re-admitted than non-Indigenous patients. The rate of methicillin-resistant Staphylococcus aureus was 24.6%, and this was associated with smoking (P = 0.049) and substance abuse (P = 0.036). Formal follow-up was not related to indirect measures of hand infection severity, such as admission duration or re-admissions. CONCLUSION: Hand infections are a common presentation to Alice Springs Hospital. Indigenous people are admitted 2.38 times longer after adjusting for age and alcohol abuse. They have a more than ninefold chance of being re-admitted to hospital than non-Indigenous people following a hand infection.

Dorsal Plating of Unstable Scaphoid Fractures and Nonunions.

Achieving stable fixation of displaced acute and chronic nonunited scaphoid fractures continues to be a challenge for the treating surgeon. The threaded compression screw has been the mainstay of treatment of these fractures for the last 3 decades; however, persistent nonunion after screw fixation has prompted development of new techniques. Recent results of volar buttress plating have been promising. We describe a novel technique of dorsal scaphoid plating. In contrast to volar plating, the dorsal plate is biomechanically more favorable as it utilizes the tension side of the scaphoid bone for dynamic compression. Dorsal scaphoid plating provides a more stable construct than the traditional Herbert screw and mitigates the need for vascular or corticocancellous bone grafting in most cases.

Azathioprine hypersensitivity presenting as cardiogenic shock and Sweet's syndrome in a patient with microscopic polyangiitis.

Azathioprine hypersensitivity is a clinical syndrome which may manifest from isolated fever and rash to multi-organ failure. This rare condition is usually self-limiting following the discontinuation of azathioprine. Therefore, it is important to maintain a high index of clinical suspicion for hypersensitivity reactions with azathioprine therapy. We report a case of azathioprine hypersensitivity in a 69-year-old woman who developed cardiogenic shock and Sweet's syndrome following the initiation of azathioprine for her underlying autoantibodies to neutrophil cytoplasmic antigens (ANCA) associated microscopic polyangiitis.