Correlation between inter-vertebral disc morphology and the results in patients undergoing Graf ligament stabilisation
Previous studies have shown Graf ligament stabilisation procedure to give mixed results in the short to medium term. The aim of this study was to correlate the pre-operative state of the disc, multifidus muscles, age of the patient, levels operated and the clinical outcome after a mean follow-up of 47 months. Graf ligament stabilisation procedure was carried out in 38 patients between 1996 and 1999. Their post-operative status was assessed using MacNab criteria. The postoperative follow-up was by postal questionnaires and review of the clinical notes. Disc morphology and multifidus muscle wasting was graded blindly and independently. The intra- and interobserver reliability was measured with kappa score and classified using the kappa classification of Landis and Koch. Correlation was measured with the help of Spearman correlation coefficient. Thirty-eight patients (100%) returned the questionnaires. Mean follow-up time was 47.55 months. Fifty-nine levels were operated on. Mean age was 39.68 years. The overall re-operation rate was 15.8%. The intra- and interobserver reliability was graded as good to substantial. Twenty-two patients (57.89%) were satisfied with the procedure. There was no statistically significant correlation between disc morphology, multifidus muscle wasting, sex, age, number of levels operated, the levels operated, and the satisfaction rate. The indications of Graf ligament stabilisation procedure are not clear. Further work is necessary to clearly identify the indication for the procedure.