The authors examined a case series of patients under the age of 18 years treated for lumbar intervertebral disc herniation. To evaluate postoperative and long-term results of surgery in patients younger than 18 years. There are only a few series, with controversial results, available on the surgical treatment of disc herniation in growing patients. Between 1975 and 1991, a consecutive series of 129 patients 9-18 years of age (average age, 16.2 years) underwent surgery for lumbar intervertebral disc herniation. Low back pain associated with leg pain was the main clinical symptom in 106 subjects (82%), back pain in 17 (13%), and leg pain in 6 (5%). Short-term results were excellent or good for 123 cases (95%), with complete pain relief in 97 (75%) and moderate but incomplete relief in 26 (20%). A total of 98 (76%) long-term responses obtained at a mean follow-up of 12.4 years revealed excellent outcomes in 40% of the cases, good in 47%, and poor in 13%. Ten patients (10%) underwent reintervention after 9 years on average (2 fusions and 8 re-explorations for herniated disc). Results have confirmed a tendency for outcomes to deteriorate between the short-term and long-term follow-up in young patients treated by discectomy: this tendency and the rate of reintervention (10%) confirmed the need for long-term follow-up of children and adolescents treated for disc herniation.