What is a myocele?

A myocele (or meningocele spuria) describes a protrusion of muscle through the skin. It can occur congenitally or traumatically.

Etiology

Congenital myoceles are rare. They are associated with:

* Spinal dysraphism

* Neurofibromatosis

Traumatic myoceles are typically the result of lacerations, punctures, or crush injuries. Muscle that herniates through a muscle defect is surrounded by a cuff of fascia. Herniation of muscle through defects of skin and fascia with no true sac results in a meatball-like protrusion.

Clinical features

Clinically, in both cases the following may be noted:

* Soft mass: soft swelling beneath the skin

* Tenderness: on palpation

* Impulse on coughing/straining: mass may become tenser or larger due to increased intra-abdominal pressure, although this may not be possible

Treatment

The treatment of choice for a myocele is surgical excision of the protruding muscle and primary closure of the wound in layers. This should not be attempted in the emergency setting due to the risk of underlying neurovascular structures which may be traumatized.