A common problem among both acoustic and electric guitar players is the development of left forearm pain. This column will expand upon a specific type of injury, cubital tunnel syndrome, which affects mostly the inner side of the forearm and the pinky side of the hand. This syndrome is probably not familiar to most guitarists, so I'll discuss the typical pain patterns associated with it.
Cubital Tunnel Syndrome begins with pain in the elbow area, along the inner side of the forearm. The pain can travel downwards towards the pinky, and can be accompanied by tingling or numbness sensations to the pinky side of the hand. The forearm muscles can be painful, and can lead to a misdiagnosis of tendonitis by an inexperienced doctor. This syndrome will usually only involve the ring and pinky fingers, since these fingers receive their nerve supply from the ulnar nerve. If the syndrome progresses, it can cause decreased function of the hand, especially grip strength. Wasting or atrophy of the pad of muscles on the palm side below the pinky finger can develop as well. Typically, the person notices that flexing the forearm tends to irritate the symptoms.
The culprit in this syndrome is compression of the ulnar nerve. Just south of the elbow, the nerve passes through the flexor carpi ulnaris muscle to travel down to the hand. A small tunnel forms in this location, and the nerve becomes surrounded on all sides. In this tunnel, the ulnar nerve sits on top of the flexor digitorum profundus muscle. A ligament forms the top layer of the tunnel. It is important to understand the function of the muscles in this tunnel, because they have play a major role in the development of the syndrome. The flexor carpi ulnaris muscle attaches to the inner part of the elbow, and its function is to flex the wrist and laterally deviate the wrist to the pinky side. The flexor digitorum profundus attaches to the medial elbow and inserts into the tips of the fingers. This muscle's function is to flex the fingers (especially the tips).
Now that you've survived the anatomy lesson, lets discuss in real life how these anatomical structures are affected with guitar playing. As I stated earlier, this syndrome typically affects guitarists in the left hand (for right handed individuals - the opposite would apply for left handed people). Why? Because the guitarist uses the left hand for playing the fret board. If we dissect the playing of a simple bar chord, we would notice 1) contraction of the thumb against the underside of the neck of the guitar, 2) a counterbalancing contraction of the opposing fingers on the top fretted side of the neck, 3) bending of the fingertips to push against the strings, 4) flattening of one finger against the neck to form the bar (usually the first finger), 4) maybe some stretching of the pinky to reach a higher fret and 5) flexion of the wrist.
Since the ulnar nerve passes between the muscles that perform flexion of the wrist, bending of the fingertips, and lateral deviation of the wrist (used in stretching the pinky to reach the higher frets), you can see how a typical bar chord can affect the muscles surrounding this nerve. With constant overuse of these muscles, they can become inflammed, or actually form "microtears" at the attachments to the elbow. The swelling involved can start squeezing down on the ulnar nerve, causing the symptoms mentioned above. This is also why bending the forearm will worsen the complaints. The ulnar nerve becomes stretched upon flexion of the elbow. If the nerve already is being pinched, the stretching is going to amplify the symptoms.
So what's a guitarist to do? For those of you who do not have symptoms and would like to prevent them from ever occuring, there's a few simple steps to take:
If you do have the symptoms mentioned in this article:
You can contact Dr. Jameson at firstname.lastname@example.org for any musician injury related questions.