A mucoid pseudocyst of a peripheral nerve is a rare and benign tumour of co
ntroversial origin. We have reviewed ten patients with a mean follow-up of
3.2 years. The tumour affected the common peroneal nerve in eight and the u
lnar nerve in two. The mean time between the onset of symptoms and diagnosi
s was 7.4 months (1.2 months to 2 years). On examination, there was pain in
eight patients and swelling in seven. Motor deficit in the corresponding n
erve territory was found in all. The diagnosis was usually confirmed by MRI
. Treatment was always surgical.
All the patients recovered, with a mean time to neurological recovery of 10
.75 months. Recurrence was seen in only one patient and was treated success
fully by further surgery. Our results are similar to those reported by othe
r authors. A successful surgical outcome depends on early diagnosis before
neurological damage has occurred.