Abstract
The use of interspinous distraction devices should remain the subject of audit and research. They are a relatively new addition to the armamentarium of surgical treatment of lumbar spinal stenosis. The reported results are variable and there are a number of different devices available. It is recognised that there is an early failure rate with interspinous distraction devices. This is a report of the clinical results after conversion to segmental lumbar decompression following a failure of interspinous distraction procedure.
18 patients had removal of device and conversion to a standard lumbar decompression at an average of 13 months after the index procedure. There were 7 females and 11 males. The average age was 68 years (range 49-85). The two youngest patients had a decompression and instrumented fusion, the others had decompression alone. Prior to the Index procedure of stand alone interspinous distraction device the average Oswestry Disability Index (ODI) was 42 and Visual Analogue Score (VAS) leg 7.2. Prior to revision the average ODI was 42 and VAS leg 6.7.
Complications: One intra operative myocardial infarction, one incidental durotomy and one post operative infection (pseudomonas isolated).
At a mean of 9 months follow up the average ODI was 23 and VAS leg 2.1. The VAS back was 1.9. The walking distance was subjectively reported as 246 yards pre op and 1100 yards post procedure. There was a clinically significant improvement in all patients.
A failed interspinous distraction device can be satisfactorily salvaged with a segmental lumbar decompression.