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

• Published in: European journal of orthopaedic surgery & traumatology Vol. 28; no. 7; pp. 1313 - 1319
• Main Authors: Schenkel, Matthias, Kaniewska, Malwina, Bühler, Tobias, Anderson, Suzanne, Eid, Karim
• Format: Journal Article
• Language: English
• Published: Paris Springer Paris 01.10.2018; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Female; Femur - diagnostic imaging; Femur - injuries; Femur - pathology; Fracture Fixation, Internal; Fracture Healing - physiology; Fractures; Hip Fractures - diagnostic imaging; Hip Fractures - pathology; Hip Fractures - physiopathology; Hip Fractures - surgery; Humans; Magnetic Resonance Imaging; Male; Medicine; Medicine & Public Health; Middle Aged; Muscle Strength - physiology; Muscle, Skeletal - diagnostic imaging; Muscle, Skeletal - pathology; Muscle, Skeletal - physiopathology; Muscular Atrophy - diagnostic imaging; Muscular Atrophy - etiology; Muscular Atrophy - pathology; Muscular Atrophy - physiopathology; Original Article • HIP - FRACTURES; Original • HIP - FRACTURES; Psoas Muscles - diagnostic imaging; Psoas Muscles - pathology; Psoas Muscles - physiopathology; Range of Motion, Articular - physiology; Retrospective Studies; Surgical Orthopedics; Traumatic Surgery; Wound Healing - physiology; Proximal femoral fracture; Iliopsoas muscle; Flexion strength; Fatty infiltration; Lesser trochanter
• ISSN: 1633-8065; 1432-1068
• DOI: 10.1007/s00590-018-2200-4

Objective To evaluate iliopsoas atrophy and loss of function after displaced lesser trochanter fracture of the hip. Design Cohort study. Setting District hospital. Patients Twenty consecutive patients with pertrochanteric fracture and displacement of the lesser trochanter of > 20 mm. Intervention Fracture fixation with either an intramedullary nail or a plate. Outcome measurements Clinical scores (Harris hip, WOMAC), hip flexion strength measurements, and magnetic resonance imaging findings. Results Compared 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. Conclusion Severe 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 evidence II.