Does Kyphectomy Improve the Quality of Life of Patients With Myelomeningocele?

BACKGROUND

Lumbar kyphosis is a complex spinal deformity occurring in approximately 8% to 20% of patients with myelomeningocele. The resulting gibbosity may cause pressure ulcers, difficulty lying down in the supine position and sitting on the ischia without support, decreasing quality of life (QOL). Surgery is generally performed to correct kyphosis and maintain vertebral alignment, but high complication rates have been reported. Despite satisfactory radiological results, the impact of surgery and its complications on health-related QOL (HRQOL) has not yet been established.

QUESTIONS/PURPOSES: Among children with myelomeningocele undergoing corrective surgery for lumbar kyphosis: (1) What is the risk of complications and reoperation after this procedure? (2) Does this procedure improve HRQOL scores in these patients?

METHODS

Between 2012 and 2013, five surgeons at three centers treated 32 patients for myelomeningocele-related kyphosis with kyphectomy and posterior instrumentation. During that period, all surgeons used the same indications for the procedure, which were progressive postural decompensation and chronic ulceration at the apex of the deformity. Data were prospectively collected, and all patients who underwent surgery were considered in this retrospective study. The legal guardians of one patient declined to sign the informed consent form, resulting in 31 patients included. A total of 9.7% (3 of 31) were lost to follow-up before the 2-year period, and the remaining 90.3% (28 of 31) were seen at a mean of 3 years (± 9 months) after surgery. The average age was 10 years, 7 months (± 21 months) at the time of surgery. The patients had a mean kyphosis angle of 130° ± 36° before surgery. This technique involved posterior fixation using S-shaped rods inserted through the foramina of S1 and pedicle screws inserted in the thoracic spine. The patients' caregivers answered both the generic and specific (neuromuscular module) Pediatric Quality of Life Inventory questionnaires preoperatively and 2 years postoperatively. The minimum clinically important difference (MCID) considered for the instruments used was 5.

RESULTS

Reoperation was performed in 68% of patients (19 of 28), mostly to treat deep infection. In all, 18% of patients (five of 28) underwent implant removal to control infection. Eleven percent (three of 28) had a loss of reduction and pseudarthrosis. The HRQOL increased from 71 ± 11 preoperatively to 76 ± 10 postoperatively (p < 0.001), resulting in a 5-point increase (95% CI 3 to 7) in the generic questionnaire score and from 71 ± 13 to 79 ± 11 (p < 0.001), resulting in an 8-point increase (95% CI 5 to 10) in the neuromuscular Paediatric Quality of Life Inventory questionnaire score, mainly in the physical health domain on both questionnaires.

CONCLUSIONS

Kyphectomy was associated with a high risk of complications and reoperations and did not seem to deliver a substantial clinical benefit for patients who underwent the procedure. Most of our HRQOL score improvements were below the minimum clinically important difference for the Pediatric Quality of Life Inventory questionnaires. Although it seems that surgeons lack a better surgical alternative when facing the challenging health impairments these patients suffer, efforts should be made to improve the technique and reduce surgical complications. Additionally, patients and caregivers should be advised of the high reoperation rate and notified that the procedure may not result in a better QOL and should thus be avoided when possible. Future studies should verify whether decreasing the complication rate could imply improvement in the HRQOL of these patients after surgery.

LEVEL OF EVIDENCE

Level IV, therapeutic study.