A 10-Year-Old Slides Past His Dad. An Uncommon Cause Of A Traumatic Injury.

HISTORY: 58-year-old male presented to clinic complaining of left knee pain. Patient reported that two weeks prior he was playing soccer with his 10-year-old son and was knocked to the ground. He reported falling to his left side, landing on his left hip. Denied any abrupt stop, twisting movement, or direct trauma to the knee. He noted an immediate burning sensation in the knee but was able to continue playing. Symptoms progressed over the course of two weeks with an increase in pain and swelling. Motrin and ice provided minimal relief. Pain intensified with bending the knee, prolonged standing, or going up/downstairs. Denied any feeling of joint instability or locking. Denied any past injuries. Past medical history included hypertension. PHYSICAL EXAMINATION: Vitals WNL. No gross deformity, but mild edema of the medial aspect of left knee. Palpable effusion overlying medial joint line. Tenderness of the medial joint line and superomedial pole of patella. No palpable deformity of the patella tendon, quadriceps tendon, adductors or abductor muscle groups. ROM grossly 0-130 bilaterally. Lachman’s, test McMurray’s test, varus/valgus stress testing, straight leg raise all negative. Patella grind positive. Strength grossly 5/5 throughout b/l lower extremities. DIFFERENTIAL DIAGNOSIS: MCL Sprain, Meniscus tear, Morel-Lavallee lesion. TEST AND RESULTS:X-Ray B/l Knee:No acute findings. Quadriceps tendon enthesophyte seen on the left patella. Mild joint space narrowing bilaterally. MRI L Knee w/o Contrast:Prepatellar bursitis and surrounding soft tissue edema. Large loculated fluid signal medially at the level of the medial patellar retinaculum and vastus medialis, deep to the subcutaneous tissues. This measures 10 cm x 5.7 cm in the axial plane maximally and measures 8 cm in superior to inferior extent. Surrounding subcutaneous soft tissue edema is seen extending posteriorly. Medial meniscus posterior horn vertical tear. Small effusion. FINAL/WORKING DIAGNOSIS: Morel-Lavallee Lesion. TREATMENT AND OUTCOMES:1. Ice and compression with ACE wrap.2. NSAIDs for pain and inflammation. 3. Initiated physical therapy for gentle ROM and modalities.4. Followed on a weekly basis for signs of improvement or infection5. There was gradual improvement in symptoms over the course of two months with return to pain free ambulation.