Assessment of strength and gait following surgical repair of isolated diaphyseal femur fracture.

Background: Intramedullary nailing is the standard of care for isolated diaphyseal fractures with high union rates, yet patients will often report forms of long-term impairment. Studies have reported residual, long-term weakness of the quadriceps and hamstrings after injury. No manuscripts have characterized how this weakness affects gait years after fracture healing.

Research Question: Do patients have normal gait and full strength of the affected limb's quadriceps and hamstrings two or more years after repair of isolated diaphyseal fracture of the femur?

Methods: Eleven participants (36 ± 19 years of age; nine females; 6.4 ± 2.2 years postop) underwent lower extremity gait and bilateral knee flexion/extension and hip abduction/adduction strength analysis. Kinematic and kinetic data were compared between limbs and to historical control data. Differences in isometric and isokinetic strengths between the affected and unaffected legs were assessed using dynamometry. Functional outcomes were also collected using SF-36 questionnaires.

Results: Significant weaknesses of the quadriceps and hamstrings were observed in the affected limb. Gait analysis data demonstrated symmetric dynamics between limbs, but increased anterior pelvic tilt, decreased hip extension, increased internal tibial rotation, slower walking speeds, and shortened stride lengths compared to control data. These gait changes resulted in altered moment demands and diminished power. The SF-36 scores in all eight categories were significantly lower in the fracture population compared to control data.

Significance: This study demonstrated strength deficits, gait abnormalities, and lower functional scores in patients at least two years after repair of diaphyseal femoral fractures indicating residual functional impairment. Future work involving functional assessments at earlier time points after surgery may be beneficial to identify and implement postoperative therapy protocols to specifically address these deficits and provide a more comprehensive recovery.