To describe complications and reoperation rates associated with degenerative spinal deformity surgery

A retrospective review of prospectively collected data from a single spinal surgeon in the United Kingdom. A total of 107 patients who underwent surgery, of 5 or more levels, for primary degenerative kyphoscoliosis between 2006 and 2012 were identified. Clinical notes were reviewed and post-operative complications, reoperation rates, length of follow up and mortality were analysed.

A total of 107 patients, average aged 66.5 years (range 52 – 85), with 80% women. 105 patients underwent posterior surgery, two patients required both anterior and posterior surgery. The average number of instrumented levels was 8.3; 10% 5 levels, 15% 6 levels, 11% 7 levels, 14% 8 levels, 15% 9 levels and 35% had fusions of 10 levels and above. 58% included fixation to sacrum or pelvis. 93% had a decompression performed and 30% had an osteotomy. There were 40 complications recorded within the follow-up period. Infection occurred in 7 patients (6.5%). All were successfully managed with debridement, antibiotic therapy and retention of implants. There were 4 dural tears (3.7%). One patient developed a post-operative DVT (0.9%). No patients sustained cord level deficits. Prevalence of mechanical complications requiring re-operation was 26% (28 patients). 5 patients (4.7) required revision surgery for symptomatic pseudarthrosis, 7 patients (6.5%) underwent revision fixation for metal work failure (broken rods/screw pull-out) and 16 patients (14.9%) underwent revision surgery to extend fixation proximally or distally due to adjacent segment disease (symptomatic proximal junction kyphosis 4.7%; osteoporotic fracture 3.7% and junctional/nerve root pain 6.5%). Overall reoperation rate was 32.5% at an average of 1.9 years following primary surgery (range 1 week–6 years). 37% patients remain on regular outpatient review (average 3.8 years following first surgery; range 2–6 years). 52% have been discharged after a mean follow-up of 2.3 years. 11 patients had died since their surgery (10.2%) at an average 4.1 years following their spinal surgery (range 1 –5.9 years).

Overall complication rate was 37.3%. 32.5% of patients were re-operated for infective or mechanical complications. 52% of patients had been discharged at an average of 2.3 years following their surgery. 10.2% of patients had died within 6 years of surgery.

The prevalence of degenerative spondylolisthesis (DS) increases with age. With an ageing population there will be increasing demands for adult deformity surgery, with associated significant financial and complication costs. The prevalence of lytic spondylolisthesis (LS) is 6–8%. Our clinical observation is that it is extremely rare to see LS in the presence of DS and therefore the objective was to formally describe the prevalence of LS in combination with DS to assess the hypothesis that 6–8% of patients with DS should also have LS. If this is not the case it may further our understanding of the pathogenesis of DS, which could aid in future prevention or treatment.

A retrospective review of erect lateral lumbar radiographs demonstrating lumbar spondylolisthesis was performed. Radiographs were identified and analysed on the hospital Synapse Picture Archiving and Communication System (PACS). Search criteria were radiographs requested by primary care and patients aged over 60.

101 patients with spondylolisthesis were identified. 89% were requested for back or leg pain. There were 89 patients with DS (69.7% women) and 12 with LS (83% men). The average age of DS and LS patient was 75 and 70 respectively (not significant). There were no cases found with both DS and LS. This was significantly different to the expected amount of 6% (p=0.03). The level of DS was at L3/4 in 11.2% (n=10), L4/5 in 79.8% (n=71) and L5/S1 in 16.9% (n=15). 2 levels were involved in 7 patients. 94.4% (n=84) demonstrated a Meyerding grade 1 slip and 5.6% (n=5) grade 2 slip. For LS the slipped level was at L5/S1 in all cases. 66.7% (n=8) had a grade 1 slip and 33.3% (n=4) a grade 2 slip.

We found no cases of lytic spondylolisthesis in the presence of degenerative spondylolisthesis. We hypothesis that the presence of spondylolysis or lytic spondylolisthesis may be protective against development of degenerative spondylolisthesis. More work is needed to explore this further.