Lumbar Spinal Canal Stenosis is a common condition in the ageing population. In Spinal decompression surgery a balance needs to be struck between the need to decompress the neural elements in the spinal canal and the risk of worsening the segmental instability that often coexists in this condition. Traditionally decompression has been supplemented with rigid stabilization e.g. fusion, which is irreversible. Recently semi-rigid or ‘soft’ stabilization philosophies have evolved. The Wallis Device is a second generation interspinous distraction/stabilization implant designed to achieve ‘soft’ segmental stabilization. In addition to stabilising the decompressed segment, it also provides a ‘block’ to full segmental extension, helping to maintain spinal canal dimensions even in the erect position.

We followed up and assessed outcomes in 50 patients (25 spinal decompression + Wallis implant and 25 spinal decompression alone). The two arms of the study were matched for gender, age and level of lumbar decompression. A single surgeon was involved in each case and carried out a standard procedure of fenestration and medial facetectomy. Outcomes were assessed during clinical follow-up as well as by telephone, and included the VAS, the Oswestry Disability Index (ODI) and the EQ5D Health Domain.

Early results suggest decreased incidence of recurrent symptoms and global improvement in all parameters measured, in those subjects that underwent Spinal decompression with Wallis stabilisation.