Ultrasound As A Cost-effective Alternative To Mri For Postoperative Knee Pain Evaluation

HISTORY: 69 year-old Female with a history of DM and atrial fibrillation, who was referred by orthopedics for right knee pain. She initially presented to the emergency room with acute nontraumatic right knee pain and was found to have crystalline arthropathy with superimposed infection. She underwent knee arthroscopic incision & drainage. However, she continued to have infrapatellar pain worse with stairs without instability and clicking. Physical therapy and corticosteroid injection provided no relief. X-ray only showed patellar enthesopathic changes and chondrocalcinosis. She was referred to Sports Medicine for further evaluation where ultrasound showed a foreign body. PHYSICAL EXAMINATION: Right knee examination revealed dimpling and discoloration over the medial joint line just medial to patellar tendon border, no effusion, tenderness to palpation over the dimpling, able to flex to 120 degrees with pain in flexion, strength 5/5, Negative McMurray's, Negative Clark's, Negative anterior and posterior drawer tests, negative valgus and varus stress tests DIFFERENTIAL DIAGNOSIS: 1.Osteoarthritis2.Abnormal Scar tissue healing3.Septic knee TEST AND RESULTS: Knee radiographs-Intact bones-Bilateral patellar enthesopathic changes-Maintained joint spaces-Bilateral chondrocalcinosis-Soft tissue are normal.Point of care ultrasound-Fiber discontinuation over the medial aspect of the knee located over the pinpoint region of pain at the medial scope portal compared to the anterolateral aspect shows improved healing with good fiber distribution. Noted foreign body approximately 0.5 cm under the medial scope portal entry. No blood flow on doppler showing evidence of tendinopathy. FINAL/WORKING DIAGNOSIS: Retained suture TREATMENT AND OUTCOMES: 1.Underwent foreign body removal significant for retained suture 2.Cleared for weight bearing as tolerated3.Began extensive course of physical therapy4.Experienced full resolution of pain and erythema5.Regained full strength and quality of life