Gait Analysis After Intertrochanteric Hip Fracture: Does Shortening Result in Gait Impairment?

Abstract

To determine the association between fracture collapse with altered gait after intertrochanteric (IT) fracture using the trochanteric fixation nail (TFN) and helical blade. Prospective cohort study. Academic Level I trauma center. Seventy-two patients with IT hip fractures (OTA/AO 31) treated between 2012 and 2016. The average age was 79.7 years (range, 51-94 years); there were 59 women and 13 men. All patients were treated with cephalomedullary nailing using the TFN (DePuy-Synthes, West Chester, PA) with a helical blade. At follow-up appointments, temporospatial gait parameters were measured and recorded. Radiographs were analyzed at the time of surgery and at each follow-up visit. Amount of radiographic femoral neck shortening was measured radiographically. Patients completed the Harris Hip Score, visual analog scale for pain, Short Form-36 Physical Component Score, and Short Form-36 Mental Component Score. The mean length of follow-up between the surgery and the gait analysis was 8.6 months (±0.7 months). The mean amount of shortening was 4.7 mm (±0.6 mm). Out of the 72 patients analyzed, there were 15 patients (20.8%) who shortened more than 8 mm, 7 patients (9.7%) who shortened 10 mm or more, and 2 patients (2.8%) who shortened more than 20 mm. Mean shortening was 3.0 mm for stable OTA/AO 31-A1 fractures, whereas the unstable patterns (OTA/AO 31-A2, 31-A3) demonstrated a mean shortening of 5.9 mm (P = 0.02). There was significant correlation between increased shortening and decreased cadence (P = 0.008), increased double support time (P < 0.001), decreased step length (P = 0.001), and increased single support asymmetry (P = 0.04) during gait analysis. The threshold of 8 mm of shortening predicted decreased cadence (P = 0.008), increased double support time (P < 0.001), and decreased step length (P = 0.006). Analysis of patient-reported outcome scores, including the Harris Hip Score, visual analog scale, SF-36 Physical Component Score, and SF-36 Mental Component Score, revealed no significant association with shortening. Results from this study indicate that shortening after cephallomedullary nailing of IT hip fractures using the TFN with a helical blade is associated with altered gait, specifically decreased cadence, increased double support time, decreased step length, and increased single support time asymmetry. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.