Ultrasound-guided injection for the diagnosis and treatment of posteromedial knee friction syndrome.

Abstract

To describe an ultrasound guided injection technique for diagnosing and treating posteromedial knee friction syndrome, which occurs between the sartorius/gracilis tendons and medial femoral condyle (MFC). Our study was IRB-approved and HIPAA-compliant. We identified patients via a retrospective review of medical records and MRI with posteromedial knee pain and isolated edema between MFC and sartorius/gracilis tendons and no evidence for meniscal tear, ruptured Baker's cyst or degenerative joint disease. Patients were referred for an ultrasound-guided procedure to inject anesthetic and corticosteroid at the site of edema. Procedures were evaluated for technical success, which was defined as satisfactory identification of the injection site and adequate delivery of medication. Follow-up was available up to 8 weeks after the procedure to determine the response and any potential complications. Fourteen subjects with MRI and symptoms of posteromedial knee friction syndrome underwent 14 injections. Technical success was achieved in all procedures, with no complications. At 8 weeks' follow-up, 92% of patients had symptom improvement. VAS before and 8 weeks after the procedure changed from 5.2 ± 2.7 to 0.9 ± 2.1 (p = 0.0002), respectively. Ultrasound-guided injection of edema between the MFC and sartorius/gracilis tendons supports the diagnosis of a posteromedial knee friction syndrome and successfully treats its associated symptoms.