Radial nerve injuries are much less common than other upper extremity neuropathies. Proximally, the radial nerve is most vulnerable in the axilla, where it can be injured by hyperabduction of the arm, which puts traction on the nerve. This is the case with "Saturday night palsy," when an intoxicated person sleeps with an arm draped over a chair. A similar circumstance occurs when the nerve is compressed against the humerus at the spiral groove. It is also seen with improper fit or use of crutches. Other sources of compression that can injure the radial nerve along its course include lipoma, fibroma, and new or previous (from callus) humerus fracture.
The radial nerve is predominantly a motor nerve, so symptoms depend on the level of injury. If the compression is proximal enough, there will be sensory loss over the dorsum of the hand, along with weakened triceps (elbow extension) and brachioradialis (elbow extension and supination) motor function. The most obvious finding in radial palsy is wristdrop and drop finger (digital extensor paralysis).
In posterior interosseous syndrome (radial tunnel syndrome) the compression is more distal; the purely motor branch of the radial nerve, the posterior interosseous nerve, is entrapped at the supinator muscle, causing only weakness in the finger extensors without affecting wrist extension.
Was this article helpful?
Discover How to Heal Yourself Naturally! Safe, All-Natural Alternatives to Taking High-Cost, Side-Effect-Laden Prescription Drugs! If you are tired of paying the high cost of prescription drugs if you are tired of worrying about prescription drug side affects or if you just dont want to risk becoming dependent on prescription drugs then have I got great news for you!