Lag screw cut-out is a serious complication of dynamic hip screw fixation in trochanteric hip fractures. Lag screw position is recognised as a crucial factor influencing the occurrence of lag screw cut-out. We propose a modification of the Tip Apex Distance (TAD) and hypothesize that it could enhance the reliability of predicting lag screw cut-out in these injuries. A retrospective study of hip fracture cases was conducted from January 2018 to July 2022. A total of 109 patients were eligible for the final analysis. The modified TAD was measured in millimetres, based on the sum of the traditional TAD in the lateral view and the net value of two distances in the anteroposterior (AP) view. The first distance is from the lag screw tip to the opposite point on the femoral head along the lag screw axis, while the second distance is from that point to the femoral head apex. The first distance is a positive value, whereas the second distance is positive if the lag screw is superior and negative if it is inferior. Receiver operating characteristic (ROC) curve analysis was used to assess the reliability of various parameters for evaluating the lag screw position within the femoral head. Factors such as reduction quality, fracture pattern according to the AO/OTA classification, TAD, Calcar-Referenced TAD, Axis Blade Angle, Parker’s ratio in the AP view, Cleveland Zone 1, and modified TAD were statistically associated with lag screw cut-out. Among the tested parameters, the novel parameter exhibited 90.1% sensitivity and 90.9% specificity for predicting lag screw cut-out at a cut-off value of 25 mm, with a p-value < 0.001. The modified TAD demonstrated the highest reliability in predicting lag screw cut-out. A value of 25 mm may potentially reduce the risk of lag screw cut-out in trochanteric hip fractures.
This study analysed the clinical and radiological outcome of
anatomical reduction of a moderate or severe stable slipped capital
femoral epiphysis (SCFE) treated by subcapital osteotomy (a modified
Dunn osteotomy) through the surgical approach described by Ganz. We prospectively studied 31 patients (32 hips; 16 females and
five males; mean age 14.3 years) with SCFE. On the Southwick classification,
ten were of moderate severity (head-shaft angle >
30° to 60°) and
22 were severe (head-shaft angle >
60°). Each underwent open reduction
and internal fixation using an intracapsular osteotomy through the
physeal growth plate after safe surgical hip dislocation. Unlike
the conventional procedure, 25 hips did not need an osteotomy of
the apophysis of the great trochanter and were managed using an
extended retinacular posterior flap. Aims
Patients and Methods
