Departments ofNeurosurgery, Newcastle General Hospital and Child Health, Royal Victoria Infirmary,

SUMMARY A 5 year old boy developed an implanta-tion dermoid tumour after a lumbar puncture in infancy. A survey of senior paediatricians has shown it to be common practice to use an unstiletted needle for lumbar puncture in small children. A stiletted needle is recommended for all such proce-dures. There is considerable evidence that epidermoid spinal cord tumours may be a late complication of lumbar puncture, particularly when it is carried out with a needle without a stylet.1 Because of this possibility it is recommended that lumbar puncture is always done with a stiletted needle.2 We report the occurrence of such a tumour in a 6 year old child who had had a lumbar puncture as an infant. Case report A chinese boy first presented at the age of 10 weeks with a short history of fever and vomiting. Menin-gitis was suspected and two unsuccessful lumbar punctures were performed. The type of needle used was not recorded. Subsequently pus cells were found in a specimen of urine and the urinary tract infection was treated with an antibiotic. An in-travenous pyelogram was carried out and was normal. He was well until 5 years and 9 months of age when he developed a pain in his left hip for which no cause was found. The pain persisted, however, and he also developed a dull ache in the lumbar region that radiated into the buttocks and was aggravated by coughing. Examination at this time showed a very stiff lumbar spine with straight leg raising limited to 450 on both sides. There was a mild weakness of hip flexors and reduced ankle jerks. There was no disturbance of sphincter function. There was no clinical evidence of either spinal dysraphism or neurofibromatosis. Plain radiographs of the lumbar spine were normal. A myelogram was then performed, and this showed a mass extending from L3 to L4 and displacing nerve roots bilaterally around it. Cerebrospinal fluid was normal. A laminectomy of L3 and L4 was carried out and a 'pearly ' mass was removed. The tumour measured 30x5 mm and was shown histologically to be a typical implantation dermoid. He made a complete recovery after the operation with no abnormal neurological signs, but he has developed noticeable keloid formation of the scar