gms | German Medical Science

Objective: Microsurgical decompression (MD) of lumbar spinal stenosis (LSS) is a high frequent spinal surgery. However, a certain amount of recurrences occur. We analysed therapy options as well as characteristics in spine imaging of patients with recurrent LSS.

Methods: In this retrospective monocentric study, we analysed 899 patients after MD of LSS within a 5-year period. Recurrent disease of the index segment was defined as recurrent narrowing of the central spinal canal, lateral recess or neural foramen, or new segmental instability, with new symptoms of claudication or sciatica. Ethical approval was obtained.

Results: 78 patients with recurrent LSS were identified (24% female, 76% male, average age 68 ± 10 years). A microsurgical decompression was performed in patients with new central spinal canal or recess stenosis without signs of instability (52 patients, 67%), and a spinal fusion was performed after occurrence of instability in dynamic X-ray radiographs, progressive spondylolisthesis, or neuroforaminal stenosis (26 patients, 33%). Average time between the first decompression and the operation on the recurrent disease was 3.7 ± 5.7 and 1.7 ± 1.1 years. In the instrumentation group, the rate of initial static spondylolisthesis was higher (23%) compared to the decompression only group (6%). In the instrumentation group, 19% were preoperatively diagnosed with new instability in functional radiographs and 58% had lateral recess or foraminal stenosis, compared to 0% instability in dynamic X-ray radiographs and 60% central spinal canal stenosis in the decompression group. In the stabilisation group, facet joints were always involved in the recurrent disease, compared to 60% in the decompression group. The percentage of initial Pfirrmann grade 4 - disc degeneration was 68% in the instrumentation group, compared to 51% in the decompression group. In the decompression group, 9 patients (17%) had to undergo a consecutive fixation operation(after 0.8 ± 1.0 years), due to new instability, progressive spondylolisthesis or foraminal stenosis.

Conclusion: Surgery of recurrent disease of lumbar spinal canal stenosis consisted either of MDor additional fusion. We characterized typical imaging characteristics in both treatment groups. The rate of spinal fusion after MD of the recurrent disease was high within 1 year after Redo-MD. Therefore surgeons should be very critical with their indication to perform a Redo-MD without instrumentation.