Analysis of the incidence and risk factors for the progression of proximal junctional kyphosis following surgical treatment for lumbar degenerative kyphosis: minimum 2-year follow-up

Abstract

BACKGROUND CONTEXT. Proximal junctional kyphosis (PJK) following surgical treatment of lumbar degenerative kyphosis (LDK) is one of the critical complications leading to the failure of instrumentation and additional extensive surgery. However, most previous studies have focused on idiopathic scoliosis resulting from variable surgical techniques. LDK usually differ from other scoliotic deformities in terms of patient characteristics and disease mechanisms. PURPOSE. Identification of the prevalence of PJK after the surgical treatment of LDK and searching for the predictable value for the progression of PJK. Study design. Retrospective comparative study. Patient sample (must be included in clinical studies). Forty-seven consecutive patients who underwent surgical correction of a sagittal imbalance due to LDK, from January 2005 to December 2008 in a single spine clinic, were evaluated with a minimum 2 years follow-up (mean 3.8 years). METHODS. Patients were divided into 2 groups: with or without the occurrence of PJK, and three categorized factors according to patient characteristics, surgical variables, and the radiographic spinopelvic parameters were evaluated. RESULTS. PJK had occurred in 29 of 47 patients (61.7%). Among variable factors, old age, upper-instrumented vertebra below L2, lumbar lordosis to PI ratio, and the sum of lumbar lordosis, and the sacral slope related to PI were found to be statistically significant. CONCLUSIONS. The overall incidence of PJK following surgical treatment of LDK patients was higher than expected. Spinal biomechanics may be changed after long instrumented fusion surgery. Thorough consideration of these factors is needed in the treatment strategy of LDK patients. A long-term follow-up study should be conducted.

Proximal Junctional Kyphosis and Proximal Junctional Failure Following Adult Spinal Deformity Surgery

“…Several authors have analyzed the incidence of PJK following ASD surgery. It has been reported from 17% to 61.7% 7 , 8 , 18 , 24 , 31 , 33 , 34 , 49 , 51) . The incidence has wide range according to the study population and the period of follow-up (F/U).…”

“…They demonstrated 40% the incidence of PJK. Lee et al 31) reported 61% of PJK about 47 patients with lumbar degenerative kyphosis surgery during 3.8-year F/U. Whereas, the incidence of PJF was reported between 1.4% and 35% 16 , 45 , 52) .…”

Posterior Ligamentous Reinforcement of the Upper Instrumented Vertebrae +1 Does Not Decrease Proximal Junctional Kyphosis in Adult Spinal Deformity

“…Proximal junctional kyphosis (PJK) is a common occurrence following surgery for adult spinal deformity with reported rates from 17% to 61.7%. 1 , 2 Although a majority of patients with PJK are asymptomatic, 3 , 4 PJK can have a significant impact on clinical outcomes 5 , 6 and can result in neurologic injury and/or progressive sagittal plane deformities. 7 PJK is among the most common causes for revision surgery in adult deformity.…”

Incidence and risk factors for the progression of proximal junctional kyphosis in degenerative lumbar scoliosis following long instrumented posterior spinal fusion

“…Previous literature have addressed the long-term follow-up proximal junctional changes following posterior spinal instrumentation for adolescent idiopathic scoliosis (AIS), lumbar degenerative kyphosis (LDK), adult spinal deformity, and the risk factors for PJK have been determined in the respective study. [ 1 12 14 ] To the best of our knowledge, no studies have demonstrated long-term follow-up results of PJK following instrumented posterior spinal fusion for DLS patients. The purpose of this study is therefore to identify the prevalence of PJK after the surgical treatment of DLS, and to search for predictable risk factors for the progression of junctional kyphosis.…”