Outcomes of dynamic hip screw augmented with trochanteric wiring for treatment of unstable type A2 intertrochanteric femur fractures

Abstract

Background: Posteromedial and greater trochanteric fragments are a major cause of telescoping and medialization of the femoral shaft in an unstable intertrochanteric fracture. This leads to significant limb shortening, fracture collapse in varus position and implant failure, which can be prevented by trochanteric wiring in addition to dynamic hip screw (DHS) fixation. The purpose of our study is to assess the outcomes of DHS augmented with trochanteric wiring in unstable type A2 intertrochanteric fractures.

Materials and methods: One hundred and two retrospective cases of unstable intertrochanteric fractures treated with DHS between January 2010 and December 2015 with a minimum follow-up period of 12 months were reviewed. Out of 102 cases, 28 were treated with DHS and derotation screw alone (Group A), while in rest 74 cases trochanteric wiring was used as an augmentation to DHS and derotation screw (Group B). Patients were evaluated clinically for range of motion, Harris hip score and Oxford hip score. Radiologically, fracture reduction, change in neck shaft angle and neck length ratio in comparison to opposite hip and union status of greater trochanter were assessed.

Results: The mean age of the patients at the time of surgery was 72 years (range 23-94 years) with 48 males and 54 females. The mean follow-up period was 20 months (range 12-48 months). The Harris hip score, Oxford hip score, shortening, attainment of weight bearing and change in neck shaft angle was not significantly different between the two groups (all p values >0.05). Incidence of greater trochanter nonunion was greater in group A (17.85%) as compared to group B (6.75%). We found significant association between occurrence of limp with varus change in neck shaft angle, decrease in neck length ratio and greater trochanteric non-union (all p values <0.05). We had 7 complications, one superficial infection, one deep vein thrombosis, 4 screw cut out and one deep infection treated with implant removal.

Conclusion: DHS augmented with trochanteric wiring in unstable intertrochanteric fractures gives similar result to group without no wiring, although greater trochanter non-union rate was more in the latter group. Limp can be prevented by anatomical or valgus fixation, augmentation of DHS to support posteromedial and greater trochanteric fragments and delayed weight bearing.

Keywords: Dynamic hip screw; Trochanteric wiring; Unstable intertrochanteric fracture.