Surgery of lumbar and thoracolumbar scolioses in adults over 50. Morbidity and survival in a multicenter retrospective cohort of 180 patients with a mean follow-up of 4.5 years.

INTRODUCTION: The increasing life expectancy of the population and the improvement in surgical and medical management of elderly patients mean that the indication for surgical treatment of adult lumbar and thoracolumbar scolioses has been extended. However the benefit/risk ratio of these procedures is still under debate. MATERIALS AND METHODS: We reviewed 180 patients, mean age 63years old with a minimum follow-up of 1year in a retrospective, continuous, multicenter study. The incidence rate of complications from surgery and the factors influencing their frequency were evaluated by uni- and multivariate analysis. The risk of a second operation was studied by actuarial survival analysis. RESULTS: After a mean follow-up of 4.5years, 79 patients (44%) presented with at least one complication, including 32% with a serious complication. The most frequent complications were mechanical. The risk factors were medical co-morbidities, the extent of fusion and the extent of the preoperative sagittal imbalance. A second operation was necessary in 25% of patients at 1year and 50% of patients at 6years of follow-up. DISCUSSION: Studies in the literature show that functional results are better with surgical treatment than with medical treatment in the management of thoracic spine and thoracolumbar deformities in patients over 50years old. An objective assessment of this deformity and associated co-morbidity should make it possible to reduce the rate of complications for this type of surgery. LEVEL OF EVIDENCE: Level IV.

Sagittal imbalance cascade for simple degenerative spine and consequences: algorithm of decision for appropriate treatment.

INTRODUCTION: The main objective of all the sagittal compensating mechanisms is to allow a subject to stand and keep an erect position. MATERIALS AND METHODS: The cascade of compensating mechanisms appears progressively with the increasing amount of imbalance of the spine until compensation is no longer possible. The loss of lumbar lordosis can be considered as the initiating event of sagittal imbalance. This loss of the normal lordosis pushes the C7 plumb line forward. RESULTS: The assessment of sagittal balance has to include to be complete: a parameter measuring the global balance of the trunk, either C7 plumb line and sacral plateau, the position of the pelvis rotation by the pelvic tilt, and a description of the position of the lower limbs. Those three parameters have been taken into account by the newly described method called full balance integrated (FBI). This evaluation is easily done on a sagittal full spine standing X-ray from C2 to the pelvis, including the first 10 cm of the femur. CONCLUSION: Three questions to answer: What is the value of the pelvis incidence? Is the patient balanced? Are there compensatory mechanisms?