Critical analysis of prognostic factors in fracture dislocation of hip

Abstract

Background: Fracture dislocation of the hip is an absolute orthopaedic emergency which is increasing day by day. There are various factors determining the functional outcome in these patients. The aim of the study is to critically analyse various prognostic factors and effect of acetabular fracture index (AFI), posterior acetabular arc angle (PAAA), head wall index (HWI) on functional outcome as well as importance of timing of relocation in development of degenerative arthritis. Materials and methods: It is a prospective study including 23 patients, above 20 years of age with study period from January 2015 to May 2018. All the patients were evaluated clinically using modified Merle d` Aubigne Postel score and radiologically by Matta et al. criteria. The average follow up period was 2 ½ years. Results: 48% of cases had excellent outcome, 31% of cases had good and 13% of cases had fair outcome. 8% of cases end with poor outcome. The quality of reduction was anatomical in 61% of cases and imperfect in 30% of cases and poor in 9% of cases. The functional outcome was good in patients with higher value of acetabular fracture index, posterior acetabular arc angle and lesser head wall index. Conclusion: The quality of reduction of fracture remains the most important factor when compared to AFI, PAAA, HWI in determining the functional outcome. The timing of relocation of hip may be of less significance in fracture dislocation. Keywords: acetabular fracture index (AFI), posterior acetabular arc angle (PAAA), head wall index (HWI), fracture dislocation Introduction Traumatic dislocation and fracture dislocation of hip is an absolute orthopedic emergency that is steadily increasing in incidence. Early recognition of these fractures, and prompt, stable reduction is the essence of successful management [1]. Several authors have recommended urgent reduction of the dislocated hip in fracture dislocation as one of the most important factors to avoid the complications of secondary arthritis, avascular necrosis, but there is a lack of agreement with respect to the allowable timing, which ranges from less than six hours to within 24 hours [1-7]. Apart from timing of relocation, various factors like the quality of reduction of the fracture, severity of injury, the age of the patient, damage to the femoral head, incarcerated fracture fragments, associated injuries, acetabular fracture index, posterior acetabular arc angle, head wall index, acetabular impaction, timing of surgery and the type of fracture plays a role in determining the functional outcome. There are very few studies in the literature suggesting the importance of tomographic parameters like acetabular fracture index, posterior acetabular arc angle, head wall index as predictors of functional outcome. So the aim of our study was to critically analyses these parameters, and determine the importance of time of relocation in determining the incidence of avascular necrosis and degenerative arthritis.