No difference in flexion power despite iliopsoas fatty degeneration in healed hip fractures with large lesser trochanter displacement

Abstract

ObjectiveTo evaluate iliopsoas atrophy and loss of function after displaced lesser trochanter fracture of the hip.DesignCohort study.SettingDistrict hospital.PatientsTwenty consecutive patients with pertrochanteric fracture and displacement of the lesser trochanter of > 20 mm.InterventionFracture fixation with either an intramedullary nail or a plate.Outcome measurementsClinical scores (Harris hip, WOMAC), hip flexion strength measurements, and magnetic resonance imaging findings.ResultsCompared with the contralateral non-operated side, the affected side showed no difference in hip flexion force in the supine upright neutral position and at 30° of flexion (205.4 N vs 221.7 N and 178.9 N vs. 192.1 N at 0° and 30° flexion, respectively). However, the affected side showed a significantly greater degree of fatty infiltration compared with the contralateral side (global fatty degeneration index 1.085 vs 0.784), predominantly within the psoas and iliacus muscles.ConclusionSevere displacement of the lesser trochanter (> 20 mm) in pertrochanteric fractures did not reduce hip flexion strength compared with the contralateral side. Displacement of the lesser trochanter in such cases can lead to fatty infiltration of the iliopsoas muscle unit. The amount of displacement of the lesser trochanter did not affect the degree of fatty infiltration.Level of evidenceII.

Inferior Outcome after Unstable Trochanteric Fracture Patterns Compared to Stable Fractures in the Elderly

“…A simultaneous clinical study reported improved functional outcome according to the Harris Hip Score after double loop cerclages compared to single loop cerclages for additional fracture reduction following nailing of trochanteric fractures, yet the study group was rather small with a limited follow-up period [ 21 ]. Contrary to these findings, Schenkel et al demonstrated no significant differences in flexion force of the hip after fracture fixation of trochanteric fractures with unfixed lesser trochanter fragments; only fatty infiltration of the iliopsoas muscle was observed [ 13 ].…”

“…Following the current opinion no specific surgical treatment of the lesser trochanter fragment is necessary during intra- or extramedullary fixation of these fractures, although it is the insertion of the iliopsoas muscle, which plays an important role for hip flexion. Study findings are contrary: while refixation of the lesser trochanter was shown to increase biomechanical stability, functional disadvantages in patients without refixation as well as no effects on flexion power after untreated trochanter displacement were observed [ 11 , 12 , 13 ].…”

The impact of the union of lesser trochanter fragments after intramedullary fixation of trochanteric femoral fractures: an X-ray based study

“…Indeed, Liu et al [ 9 ] compared intertrochanteric fracture patients with and without preoperative LT integrity retrospectively and reported no significant difference between the two groups, supporting the present study. Clinical studies reported no relationship between LT dislocation and strength of hip flexion [ 24 , 25 ].…”

When to Reduce and Fix Displaced Lesser Trochanter in Treatment of Trochanteric Fracture: A Systematic Review

“…Trochanteric fractures account for a significant proportion of hip fractures, ranging from 45 to 50%, in which 50-60% are classified unstable (2). According to the most used classification systems, Arbeitsgemeinschaft fur Osteosynthesefragen foundation and the Orthopedic Trauma Association (AO/OTA) classification and Evans-Jensen classification, this pattern of fracture may involve four fragments the distal femoral fragment, the femoral neck, the greater trochanter, and the lesser trochanter (LT) (3). It is accepted that orthopedists should try to anatomically reduce and fix the two main fragments and greater trochanter (4,5).…”

“…Lesser trochanter, an important structure of the femoral posteromedial wall, plays a pivotal role in stress distribution and reconstruction stability in trochanteric fracture (6). However, the necessity of reducing and fixing LT fragments remains controversial (2)(3)(4). At present, the most commonly used clinically operated protocols for trochanteric fracture include extramedullary fixation devices [e.g., dynamic hip screw (DHS)], intramedullary fixation devices[e.g., proximal femoral nail anti-rotation (PFNA)], and hip arthroplasty (e.g., hemiarthroplasty) (7,8), but none of them are designed to fix the displaced LT. On the contrary, those orthopedic surgeons who advocate fixing the displaced LT have proposed kinds of fixation devices and skills since last century, including lag screw (9), cerclage wire (Figure 1) (2), double cables (10), candy-package (11), modified candy-package (12), etc.…”