Imaging in the Diagnosis of Symptomatic Forearm Muscle Herniation.

ABSTRACT

Symptomatic muscle herniations are an unusual cause of upper extremity pain that is rarely reported in the literature. Out of 18 reported cases of upper extremity herniations, only 3 were caused by strenuous exertion6. Dynamic ultrasound and Dynamic MRI test are the very good tool for diagnosis of muscle herniation, FNAC and biopsy are rarely needed. This article describes a successful repair of a 22yr old manual worker’s ventral forearm herniation with polypropylene mesh. Prevalence Muscle herniation in an extremity is a well-known cause of pain, even though there have been extremely few documented cases. In a 2009 report published by the “Journal of Hand and Microsurgery,” only 200 cases of herniated muscles of the extremities had been reported since the mid-1800s, and only 17 cases of muscle herniation in the upper limb have been described10. Characteristics A herniated muscle in the forearm can cause mild to severe localized pain, affect grip, cause nerve pain or have no physical symptoms at all. Causes of documented cases include sporting or occupational activities, or an unrelated primary medical condition. Patients usually have a swollen mass that increases in size when the affected muscle is engaged and decreases when the muscles are relaxed. One differential diagnosis for a herniated forearm muscle is a tumor. Muscle herniation in the forearm typically affects males in their adolescent or young-adult years1. We report a case of a disappearing forearm nodule that appeared with muscle contraction. This is characteristic of a transfascial muscle hernia. Ultrasound and MRI are the key to identifying an area of fascial alteration. Treatment alternatives of this unusual condition are discussed.