Nerve Injuries Caused by Accident or Operation
Injuries to the ends of nerve branches are occasionally caused as the result of an accident or following certain operations, especially various foot-operations, but also blood vessel operations such as, for example, the removal of varicose veins because not all nerves can be protected.
In this case, surgery to release the scarred nerve or sink the injured painful nerve ends under the muscles (see neuroma) can be sensible and helpful.
A test-infiltration using local anaesthetic can aid diagnosis or possibly be very helpful in therapy. As well as having identified the characteristic symptoms of nerve injury, further neurophysiological tests are carried out in order to confirm the diagnosis. These tests measure the nerve conduction velocity (NCV), which can be reduced in damaged nerves. Electromyography tests can possibly also identify which muscles are affected. However, despite nerve compression being present, neurographic evidence of this can sometimes be very difficult to find or not possible to document at all, especially if there is additional nerve damage due to diabetes or another disease.
As further ambiguity concerning the exact position of the damage can exist, an experienced surgeon should never disregard thorough clinical testing (positive tap sign, Tinel’s sign). The possible results of the operation can be assessed pre-operatively in the form of creating a nerve block by injecting a local anaesthetic. If the symptoms are significantly relieved, one can assume they are being caused by nerve compression. An x-ray of the joint or the surrounding bones is necessary to rule out any compression caused by calcification.