Reliability of two-dimensional computed tomography for measuring hip anatomy.

PURPOSE: To evaluate the reliability (inter- and intra-observer variability) of 4 hip anatomies using 2-dimensional pelvic computed tomography (CT). METHODS: Two-dimensional pelvic CT of 10 men and 10 women aged 33 to 89 (mean, 69) years presenting with non-orthopaedic conditions within one month were evaluated by 3 observers. The centre-edge angle of Wiberg, the Sharp angle, the acetabular depth ratio of Murray, and the acetabular anteversion angle of every hip were measured by each observer. After 6 weeks, these measurements were repeated. Reliability was evaluated using intraclass correlation coefficient (ICC), which represents the variation between patients as a percentage of the variation from all 3 sources (patients, inter-observers, and intra-observers). The ICC was classified as poor (<0.20), fair (0.21-0.40), moderate (0.41-0.60), substantial (0.61-0.80), and excellent (0.81-1.00). RESULTS: Reliability was substantial for the Sharp angle (ICC=0.74), the acetabular anteversion angle (ICC=0.69), and the acetabular depth ratio of Murray (ICC=0.62), and was fair for the centre-edge angle of Wiberg (ICC=0.40). CONCLUSION: The Sharp angle, the acetabular anteversion angle, and the acetabular depth ratio of Murray could be reliably measured using 2-dimensional CT. These measurements are appropriate for population-based studies of hip anatomy.

Acutely irreducible ankle fracture dislocation: a report of a Bosworth fracture and its management.

BACKGROUND: Acutely irreducible ankle fractures are uncommon. Irreducibility caused by interposition of soft tissue and entrapment of fracture fragments has been well described. An irreducible ankle fracture due to a locked fibular shaft fragment behind the tibia, a Bosworth fracture, is a rare injury. CASE REPORT: We describe a Bosworth fracture in a 19-year-old man subsequent to a fall. CONCLUSION: The Bosworth fracture dislocation is a rare injury to the ankle, the correct diagnosis of which depends on awareness of the variant and careful evaluation of the initial clinical and radiographic features. As with our patient, a good outcome is achievable despite the severe nature of these injuries.

Irreducible tibial pilon fracture caused by incarceration of the fibula in the tibial medullary canal.

Fractures can be irreducible for several reasons, including soft tissue or bone fragment interposition. We report an unusual fracture configuration of a comminuted tibial pilon fracture in which the distal fibular shaft fragment was occupying the medullary canal of the proximal tibial shaft fragment and inhibiting reduction and fixation. To the best of our knowledge, this has not been previously reported in a published study.