Functional Movement Analysis in the Differential Diagnosis of a Patient with a Posterolateral Corner Knee Injury.
A typical physical examination consists of visual observation, palpation, and range of motion, along with special testing for structural integrity. This information tells the diagnostician little about function. Currently, there is limited research on the diagnostic benefits of utilizing Functional Movement Analysis (FMA) and its role in the diagnostic process. This case report describes a false negative MRI and physical examination from two board certified orthopedic surgeons, which then required a systematic and thorough investigation of history, mechanism, and functional movement analysis by the physical therapist, leading to a non-traditional series of images to establish an accurate diagnosis.
The second orthopedic surgeon performed a comprehensive physical examination, which included special testing for ligamentous instability. Full-length bilateral weight-bearing radiographs were ordered to assess bony mal-alignment as a possible cause for the abnormal gait pattern. These films were negative for pathology. Strength, Range of Motion (ROM), and special testing for ligamentous instability and meniscal injury were all unremarkable.
The patient may have been avoiding the 15 degrees of knee flexion used for shock absorption during loading response in order to avoid the compressive forces at the patella associated with quadriceps contraction. A meniscal tear could cause the tibiofemoral joint to lock in extension during swing.9
A meniscal tear could also lead to decreased joint congruency, which decreases stability.10 Ligamentous laxity or a tear would also lead to decreased stability of the joint. A common compensation to improve joint stability is to fully extend the knee. Locking the knee in full extension makes the joint more stable by increasing joint congruency.
Sport Exerc Med Open J. 2015; 1(2): 47-53. doi: 10.17140/SEMOJ-1-108
