OUTCOME OF ANTERIOR LUMBAR INTERBODY FUSION [ALIF] USING THE HARTSHILL HORSESHOE CAGE VS. SINGLE LEVEL GRAF LIGAMENT STABILISATION.

Abstract

To compare the effectiveness of ALIF, using the Hartshill Horseshoe cage, and Graf ligamentoplasty for stabilisation of comparable severity of degenerative disc disease.

Between 1995 and 1997, 27 patients who had single level ALIF with Hartshill Horseshoe cage [group A], and 28 patients who had single level Graf ligamentoplasty [group B] were assessed by Oswestry disability index, a subjective score, Zung Depression Scale [ZDS], and Modified Somatic Perception Questionnaire [MSPQ]. The two groups were similar in age and sex distribution. The patients were randomized, and procedures were all undertaken primarily for symptoms of back pain, although some patients in each group reported some leg pain. No patients with the ALIF group had any MRI evidence of neurological compromise. Where there was any degeneration at more than 1 level, discography was undertaken (8 patients in each group) confirming an isolated pain source at a single level. The duration of back symptoms and leg symptoms in the two groups was similar. There was some difference in the distribution of the MRI grade of disc degeneration between the 2 groups, but this did not reach statistical significance. Following is the characteristic of the 2 groups:

In this group, Graf ligamentoplasty procedure had a statistically significant better outcome than ALIF with the Hartshill horseshoe cage.

This may be due to the retention of some degree of normal mobility of the affected segments after stabilisation with Graf ligaments. However, at a minimum follow-up of 2 years, these represent only medium term results. There is a potential for a change in the outcome in the long term.