Knee Injury – Recreational Runner

Abstract

HISTORY: Case of a 41 year-old army soldier who had an acute bilateral knee giveaway weakness while jogging. After running for a mile, his left knee gaveway and he fell to the floor. He stood up without difficulties and ambulated for a short distance when he fell again due to right knee weakness. He had difficulty ambulating, although he felt no pain. During his ER visit, he had a third fall resulting in a right lateral malleolus fracture. Orthopedics was consulted and performed bilateral patellar tendon repair and right lateral malleolus ORIF. He was discharged home with bilateral hinged knee braces locked at full extension and weight-bearing precautions. Two months post-op, he was admitted to the acute inpatient rehabilitation ward of the VA Caribbean Healthcare. No past medical history of systemic conditions or regular medications. PHYSICAL EXAMINATION: Examination revealed bilateral knee valgus deformity, mild soft tissue swelling and bilateral pes planus. He had full knee extension and limited knee flexion to 90 degrees. Knee special tests were negative for meniscal, cruciate ligament or collateral ligament injury. Neurovascular exam was unremarkable. DIFFERENTIAL DIAGNOSIS: 1. Patellar tendon rupture 2. Quadriceps tendon rupture 3. Anterior cruciate ligament sprain 4. Meniscal injury 5. Collateral ligament sprain TEST AND RESULTS: 1. Bilateral knee MRI: Bilateral full-thickness tear of proximal patellar tendon with cephalad patellar displacement, medial and lateral patellar retinacula tears, and extensive soft tissue edema. Right high-grade partial versus full-thickness anterior cruciate ligament tear and anterior horn lateral meniscus tear. Left posterior horn medial meniscus tear. 2. Bilateral Knee X-ray: Bilateral patella alta. 3. Labs: Essentially normal except for low vitamin D and positive qualitative ANA test. FINAL/WORKING DIAGNOSIS: Atraumatic bilateral patellar tendon rupture TREATMENT AND OUTCOMES: 1. Outpatient-based physical therapy was provided with emphasis on ROM completion, progression of quadriceps strengthening and neuromuscular retraining. 2. He achieved full ROM in both knees and independence in ADL’s and ambulation. 3. Return to recreational sports recommendations included to avoid high impact activities, such as running, until 9-12 months post-op follow up.