Failures and revisions in surgery for sagittal imbalance: analysis of factors influencing failure.
BACKGROUND
Sagittal imbalance is an important risk factor for spinal disability, pain and loss of health related quality of life. Its correction has a positive impact on these outcomes. Still, it is a very aggressive surgery, with a high revision rate. The aim of this study is to analyze the most important causes of failure of surgery for correction of sagittal imbalance.


METHODS
In this retrospective observational cohort study twelve patients who previously underwent surgery for sagittal imbalance correction were revised in the period 2009-10. We analyzed angular parameters of sagittal balance before and after primary surgery, type of instrumentation, modality of fusion, implant density, instrumented levels, modality of failure, time from first surgery and angular parameters after revision.


CONCLUSIONS
Causes of failure were insufficient correction, junctional kyphosis, screw loosening and pseudoarthrosis with rod breakage. In every case, patients presented a new onset or a worsening of sagittal imbalance and pain.
IVth Spine Surgery Division, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy, pberjano@gmail.com.
P
P
Berjano
R
R
Bassani
G
G
Casero
A
A
Sinigaglia
R
R
Cecchinato
C
C
Lamartina
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016268:Internal Fixators; D007738:Kyphosis / Q000601:surgery*; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods*; D017211:Treatment Failure