We evaluated 56 patients for neurological deficit after enucleation of a histopathologically confirmed schwannoma of the upper limb. Immediately after the operation, 41 patients (73.2%) had developed a new neurological deficit: ten of these had a major deficit such as severe motor or sensory loss, or intolerable neuropathic pain. The mean tumour size had been significantly larger in patients with a major neurological deficit than in those with a minor or no deficit. After a mean 25.4 months (12 to 85), 39 patients (70%) had no residual neurological deficit, and the other 17 (30%) had only hypoaesthesia, paraesthesiae or mild motor weakness.
This study suggests that a schwannoma in the upper limb can be removed with an acceptable risk of injury to the nerve, although a transient neurological deficit occurs regularly after the operation. Biopsy is not advised. Patients should be informed pre-operatively about the possibility of damage to the nerve: meticulous dissection is required to minimise this.