Anterior Interosseous Syndrome is an entrapment of a nerve in the forearm resulting in numerous hand sensations and limitations. Anterior Interosseous Syndrome can occur in people with either forceful forearm muscle contraction or from repetitive activity. Pain and muscle fatigue occur in the forearm. In some cases the person has difficulty with fine hand movements, such as pinching the thumb and the index finger together or writing.
The Anterior Interosseous nerve is a branch of the median nerve. It can become entrapped or compressed at several locations. Since the nerve controls muscle function of the flexor policis longus and index finger flexor digitorum profundus, weakness in these muscles occur. They control the pinching motion that occurs with the tip of the index finger and thumb. Holding and writing with a pen becomes very difficult with entrapment of this nerve.
There should not be a loss of sensation with Anterior Interosseous Syndrome, since the nerve controls only muscle functions. A loss in sensation would suggest median nerve involvement before the branch of the Anterior Interosseous nerve.
Home treatment involves avoiding aggravating activities, such as pushing, picking, holding, and grabbing motions. Rest and ice therapy can be very helpful to reduce the pain and muscle spasms. Light stretching and self massage can be beneficial.
Conservative treatment is very successful and removing the nerve entrapment. Your provider will work to decrease the muscle spasms and inflammation in the offending musculature. Soft tissue therapy is very effective for entrapments that involve the muscles in the forearm. Graston Technique, Active Release, and massage therapy will decrease the pressure on the nerve.
Electrodiangostic studies are considered the gold standard for identifying denervation injuries. It may be considered by your provider.
If conservative treatment does not produce results within 4 to 6 weeks, a referral to a surgeon may be considered.
Anterior Interosseous Syndrome can easily be confused with Carpal Tunnel because of the hand muscle weakness; however, it is distinctly different and needs to be treated accordingly. Seek help from an experienced provider with works with entrapment syndromes.