1410 - Diagnosis of Tibial Stress Fracture via Musculoskeletal Ultrasound: A Case Report

A 34 year old female was referred for left ankle pain. Pain began during a run 9 weeks prior. Pain localized to left medial ankle and medial tibia, and she could not bear weight. After 6 weeks of PT with WBAT, patient was still experiencing significant pain, prompting PM&R evaluation.

On exam, patient had decreased active ROM in dorsiflexion, plantarflexion, eversion, and inversion due to pain. There was diffuse soft tissue swelling along the left medial ankle and tibia, with exquisite tenderness along the medial distal third tibia. 

Tibia/fibula x-rays done at time of injury and 2 weeks post were normal. MRI of left lower extremity done 6 weeks post revealed stress reactive change but was negative for stress fracture. Diagnostic ultrasound of medial tibia done in clinic revealed focal hyperechoic elevation of periosteum, cortical irregularity and disruption of bony cortex consistent with stress fracture.

Discussions: Patient is an active young female who sustained a tibial stress fracture. While x-ray and MRI studies were negative for stress fracture, diagnostic ultrasound revealed bony changes consistent with stress fracture. Musculoskeletal ultrasound is a noninvasive, inexpensive, dynamic imaging technique that is a useful tool in diagnosing suspected stress fractures not visualized on x-ray or MRI.

Conclusions: Musculoskeletal ultrasound is useful for diagnosis of stress fracture where clinical presentation supports diagnosis but x-ray and MRI are negative.  Consistent utilization of diagnostic ultrasound offers additional clinical insight in these cases.  Musculoskeletal ultrasound skills improve a physician’s ability to diagnose and treat common musculoskeletal pathologies, like stress fractures, as early as possible. Musculoskeletal ultrasound enables physicians to deliver high value care to their patients with a cost-effective, real time, dynamic study of their injury.