Proximal Junctional Kyphosis in Primary Adult Deformity Surgery: Evaluation of 20 Degrees as a Critical Angle.
ABSTRACT BACKGROUND:: Multiple studies have reported on the prevalence of proximal junctional kyphosis (PJK) following spinal deformity surgery; however, none have demonstrated its significance with respect to functional outcome scores or revision surgery. OBJECTIVE:: To evaluate if 20° is a possible critical PJK angle in primary adult scoliosis surgery patients as a threshold for worse patient-reported outcomes. METHODS:: Clinical and radiographic data of 90 consecutive primary surgical patients at a single institution (2002-2007) with adult idiopathic/degenerative scoliosis and 2 yr minimum follow-up were analyzed. Assessment included radiographic measurements, but most notably sagittal Cobb angle of the PJ angle at pre-op, between 1-2 months, 2 yrs, and ultimate follow-up. RESULTS:: Prevalence of PJK ≥ 20° at 3.5 years was 27.8% (N=25). Those with PJK ≥ 20° at ultimate follow-up were older (mean 56 vs. 46yrs.), had lower number of levels fused (median 8 vs. 11), and were proximally fused to the lower thoracic spine more often than upper thoracic spine (all P <.001). PJK ≥ 20° was associated with significantly higher BMI and fusion to the sacrum with iliac screws (P<0.016, P<0.029 respectively). Scoliosis Research Society (SRS) outcome score changes were lower for PJK patients, but not significantly different from those in the non-PJK group. CONCLUSION:: PJK ≥ 20° in primary adult idiopathic/degenerative scoliosis does not lead to revision surgery for PJK, but is univariately associated with older age, shorter constructs starting in the lower thoracic spine, obesity, and fusion to the sacrum. The negative results, supported by SRS outcome data, provide important guidance on the post-operative management of such PJK patients.
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ABSTRACT: Proximal junctional kyphosis (PJK) is a common radiographic finding following long spinal fusions. Whether PJK leads to negative clinical outcome is currently debatable. A systematic review was performed to assess the prevalence, risk factors, and treatments of PJK. Literature search was conducted on PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials using the terms 'proximal junctional kyphosis' and 'proximal junctional failure'. Excluding reviews, commentaries, and case reports, we analyzed 33 studies that reported the prevalence rate, risk factors, and discussions on PJK following spinal deformity surgery. The prevalence rates varied widely from 6 to 61.7 %. Numerous studies reported that clinical outcomes for patients with PJK were not significantly different from those without, except in one recent study in which adult patients with PJK experienced more pain. Risk factors for PJK included age at operation, low bone mineral density, shorter fusion constructs, upper instrumented vertebrae below L2, and inadequate restoration of global sagittal balance. Prevalence of PJK following long spinal fusion for adult spinal deformity was high but not clinically significant. Careful and detailed preoperative planning and surgical execution may reduce PJK in adult spinal deformity patients.European Spine Journal 09/2014; 23(12). DOI:10.1007/s00586-014-3531-4 · 2.47 Impact Factor
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ABSTRACT: To analyze risk factors for an increase in proximal junctional angle (PJA) after posterior selective thoracolumbar/lumbar (TL/L) curve fusion in patients with adolescent idiopathic scoliosis (AIS).European Spine Journal 10/2014; DOI:10.1007/s00586-014-3639-6 · 2.47 Impact Factor