Introduction: Application of dynamic hip screw (DHS) implant for the treatment of unstable intertrochanteric fractures continues to raise concern related to risk of lag screw cut-out with or without subsequent damage to the acetabulum. Measurement of tip-apex distances (TAD) has been recommended to guide the optimal placement of lag screw and to predict subsequent risk of screw cut-out. In this study, the value of TAD was evaluated to verify its usefulness.
Methods: This is a retrospective study of 33 consecutive patients with intertrochanteric fracture treated with DHS. Demographic data of the patients were traced from their case notes. Post-operative radiographs were reviewed by focusing on measurement of TAD on anteroposterior and lateral radiographs. Radiographs at one year follow-up were reviewed to depict any fixation-related failure or complication.
Results: Fifty two percent of patients did not achieved the recommended TAD of ≤ 25mm. The mean post-operative TAD was 25.9mm and elderly patients were likely to achieve TAD of ≤ 25mm. The overall complication rate of 6% was attributed to screw cut-out in two cases. The unstable left-sided fracture was identified to be a potential risk for screw cut-out or migration.
Conclusion: TAD is a valuable measurement to guide optimal placement of lag screw during DHS fixation of intertrochanteric fracture.
KEYWORDS: Intertrochanteric fracture, dynamic hip screw, tip-apex distance, screw cut-out
Langerhans cell histiocytosis of the spine frequently presents as a solitary lesion and rarely results in neurological deficit. Involvement of thyroid tissue is also rare, even in multifocal disease presentations. We present an unusual variant of Langerhans cell histiocytosis in a 37-year-old man presenting with profound quadriparesis and incidental thyroid involvement. MR imaging and skeletal radiographs revealed widespread involvement of the spine. The patient underwent surgical resection of the tumour and stabilization of the spine. Diagnosis was confirmed by histological and immunohistochemistry analysis. Langerhans cell histiocytosis should be included in the differential diagnosis of radiolucent lesions of the spine in adults.
Spinal neurofibromas occur sporadically and typically occur in association with neurofibromatosis 1. Patients afflicted with neurofibromatosis 1 usually present with involvement of several nerve roots. This report describes the case of a 14- year-old child with a large intraspinal, but extradural tumour with paraspinal extension, dumbbell neurofibroma of the cervical region extending from the C2 to C4 vertebrae. The lesions were readily detected by MR imaging and were successfully resected in a two-stage surgery. The time interval between the first and second surgery was one month. We provide a brief review of the literature regarding various surgical approaches, emphasising the utility of anterior and posterior approaches.