Functional Movement Analysis in the Differential Diagnosis of a Patient with a Posterolateral Corner Knee Injury

Abstract

Study Design: Resident’s case study.
Background and Purpose: Functional Movement Analysis (FMA) including observational gait analysis are powerful tools that can be used to guide patient examination and differential diagnosis process.
Case description: An 18-year-old female was referred to physical therapy with a diagnosis of gait abnormality and a chief complaint of left medial knee and left medial hip pain. Two orthopedic surgeons suspected neurologic pathology due to inconclusive findings on physical examination, an abnormal antalgic gait pattern, and negative findings on Magnetic Resonance Imaging (MRI) and radiographic studies. The physical therapist gathered a comprehensive subjective history, and performed a functional movement analysis including observational gait analysis. The findings were used to guide a full musculoskeletal examination. Correlating the
functional movement analysis with subjective history and comprehensive musculoskeletal examination, the therapist found the patient to have subtle but definite lateral knee joint laxity. This was hypothesized to be driving the abnormal gait pattern and causing her hip and knee pain.
Outcomes: Stress radiographs, suggested by the physical therapist, were ordered and confirmed the therapist’s finding of lateral knee instability. The patient subsequently had surgery to repair and augment her popliteal fibular ligament and lateral collateral ligament. She underwent post operative physical therapy, and returned to her prior level of function with full resolution of her gait deviations and pain.
Discussion: Functional movement analysis is a powerful and unique tool that clinicians can use when evaluating and treating patients.
Level of Evidence: Therapy, level 4.