Author: Joshua Sole, MD
Co Author #1: Jay Smith, MD

Patient Presentation:
A 61 year-old right-handed female presented to the Sports Medicine Clinic with bilateral knee pain and swelling.

History:
The patient's symptoms began in the left knee after starting Zumba classes 2 months prior. She was initially asymptomatic until the Zumba floor surface was changed. She endorsed lateral and medial left knee pain with posterior swelling 2 weeks after beginning Zumba. She denied anti-inflammatory use but had used ice. She denied systemic complaints or history of rheumatologic or connective tissue disease.

An Musculoskeletal (MSK) ultrasound guided left knee joint aspiration and injection was performed. Physical therapy, ice massage, and compressive knee sleeves were also recommended.

She returned 1.5 months later with continued left knee pain, which had initially improved following the injection. Upon resuming Zumba, her left knee pain and posterior swelling recurred, now with similar symptoms in her right knee.

A diagnostic MSK ultrasound revealed bilateral knee joint effusions and Baker's cysts. Bilateral MSK Ultrasound-guided cyst injections and aspirations and knee joint aspirations and injections were performed.

She then presented one month later with increased right calf pain, swelling, tightness and peri-malleolar ecchymoses. Her pain waxed and waned worsening by day's end. She denied knee trauma or injury. She denied any paresthesias.

Physical Exam:
Gait was non-antalgic. Single leg squat was difficult given her knee fullness. She had normal patellar mobility with palpable crepitus. Significant edema of the right gastrocnemius and soleus was apparent, tracking distally without a palpable popliteal mass. Remarkable tenderness across her medical gastrocnemius was appreciated. Knee ROM was 0-120 degree flexion with end-range posterior knee pain. Mild lateral joint line tenderness was appreciated. Pseudolaxity was apparent with valgus and varus stress. Grinding and crepitus with McMurray's was elicited without pain or locking. Ankle ROM was normal except pain with dorsiflexion. Neurovascular exam was unremarkable. Peri-malleolar ecchymoses were present across the medial and lateral ankle.

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