[Lumbar arthrodesis: results after more than 10 years]

Two hundred and seventy four patients had a lumbar spine fusion between 1949/1971. Seventy-five of them were available for review more than 10 years after the procedure. There were twenty spondylolisthesis, forty-eight degenerative discopathies, six cases of Pott's disease and one benign tumour. All the patients had been treated conservatively before the surgical procedure for an average of 7 years and were still complaining of chronic low back pain. All the cases reviewed had fused. The functional results were not related to the surgical technique, which varied during this period: eight posterior mid-line grafts, seventeen interbody fusions and fifty combined anterior and posterior approaches sometimes used because of a primary failure of fusion and no postero-lateral fusions. The average follow-up was 13 years with a range from 10 to 26 years. The clinical results were satisfactory in 74 p. 100 of the cases. There were thirteen failures. Seven of these patients had been operated on before the era of systematic preoperative discography and psychological evaluation and the failure was primary. Other failures were observed at about the tenth post-operative year. The results were better in spondylolisthesis with isthmic lesions, rather than in degenerative spondylolisthesis. They were better in pure low back pain than when the pain associated with sciatica. They were better when fusion was limited to one or two levels. Radiographs ten years after the procedure frequently showed evidence of degenerative lesions of the disc above the level of the fusion and, at the same time, some slipping of the upper vertebra. Fortunately, there was no correlation between the radiological appearances and the clinical results.