A male adolescent aged 15 years presented with lumps on the lower extremities that have developed progressively over two months. The lesions caused him pain during physical activity and limited his ability to exercise. He was otherwise healthy, with no relevant medical history, and an athlete. The examination at rest revealed three lumps on the right lower limb (Fig. 1) and two on the left, soft to the touch, that were not tender, red or warm, located in the tibialis anterior region. The lumps disappeared upon muscle contraction (Fig. 2). The ultrasound scan revealed a defect in the muscular fascia, in absence of findings suggestive of lipoma or vascular lesions (Fig. 3) (Appendix B, Video). The patient was managed conservatively with rest from sports and referred to traumatology.

Figure 1.

Muscles at rest.

Figure 2.

Muscles contracted.

Figure 3.

Ultrasound images. Right side, muscles at rest; left side, muscles contracted.

Muscle hernias are a rare condition in clinical practice and tend to be underdiagnosed or confused with other soft-tissue disorders. Most cases occur in male young adults and tend to involve the lower extremities, particularly the tibialis anterior muscle.1–3 The approach to treatment is conservative and based on rest. Surgical treatment may be considered for cases with disabling pain.1,2