Abstract
INTRODUCTION: The tensor fasciae suralis is an aberrant muscle frequently identified in cadaveric studies and MRI studies; however, it has been rarely reported in clinical studies. We present a case of recurrent popliteal pain in a young adult male and our experience with its diagnosis and treatment. CASE PRESENTATION: A 20-year-old active-duty soldier presented with recurrent right popliteal pain, initially triggered by intense physical activity during military training. Pain subsided with rest but recurred after strenuous exercises, such as soccer. Examination revealed a palpable soft mass with mild tenderness and swelling in the popliteal region. Ultrasonography identified an aberrant tensor fasciae suralis muscle with perifascial edema, originating from the semimembranosus muscle and attaching to the fascia of the medial gastrocnemius. MRI confirmed the findings with edema at its boundary. Conservative management led to symptom improvement. A follow-up ultrasound six months later showed resolution of swelling. CONCLUSION: This case highlights the importance of recognizing the TFS muscle to avoid misdiagnosis and unnecessary interventions.