Incidence and risk factors for postoperative shoulder imbalance in scoliosis: a systematic review and meta-analysis

Abstract

The pooled incidence of PSI in scoliosis was 25%. Risser sign, preoperative LC, postoperative RSH, correction rate of PTC at follow-up, correction rate of MTC at follow-up, and LC at follow-up were risk factors for PSI in patients with scoliosis. Adding-on might be a compensatory mechanism for PSI. It is recommended that (1) sufficient correction of PTC and moderate correction of MTC and LC in the operation should be performed; (2) PSI should be prevented not only for the patients' postoperative appearance, but also for preventing the adding-on phenomenon.

Hooks at the Upper Instrumented Vertebra Can Adjust Postoperative Shoulder Balance in Patients with Adolescent Idiopathic Scoliosis: 5 Years or More of Follow-up

“…Factors that can affect shoulder balance after AIS reportedly include the degree of the lumbar spine curvature and the PT and MT curves correction rates [4]. To prevent PSI, the PT curve must be adequately corrected while avoiding excessive corrections of the MT and lumbar curves.…”

“…In the Lenke 1 curve, various factors have been reported as risk factors of PSI [4,5,7,8,11-13]. Changes in the PT, MT, and lumbar curves from preoperative to postoperative affected the postoperative shoulder balance in a meta-analysis [4]. Excessive correction of the MT curve is a momentous cause of PSI.…”

“…Since spinal fusions for adolescent idiopathic scoliosis (AIS) are performed on adolescent patients, its appearance is one of the crucial concerns, along with back pain, function, and quality of life [1-3]. Although shoulder imbalance is a critical concern after spinal fusions, the prevalence of postoperative shoulder imbalance (PSI) is reportedly as high as 25% [4]. Reportedly, the self-image of the shoulder balance in postoperative patients correlates with X-ray evaluation [5].…”

“…Lately, segmental pedicle screw fixation has been extensively used, and a study has reported improvement in the correction rate [6]. In addition, PSI due to excessive correction of the main thoracic (MT) curve has been reported [4]. Namikawa et al [7] highlighted the significance of avoiding the shoulder balance defects immediately postoperatively, as PSI does not change after 29-month follow-up.…”

Association Between Incorrect Posture and Adolescent Idiopathic Scoliosis Among Chinese Adolescents: Findings From a Large-Scale Population-Based Study

“…Some potential influencing factors (such as genetic basis, neurophysiological dysfunction, or skeletal growth) have been identified but not confirmed (2). In previous studies, many researchers have discussed how a patient's body asymmetry [e.g., shoulder imbalance (7), scapular tilt (8), and asymmetric spinal loading (9)] occurred after being diagnosed with scoliosis. However, in our previous large-scale scoliosis screening study (10), we found that the majority of adolescents with scoliosis could be screened for body asymmetry (e.g., shoulder-height difference, scapula prominence, lumbar concave, etc.)…”