Dynamic Changes in Lumbar Spine Kinematics During Gait May Explain Improvement in Back Pain and Disability in Patients With Hip-Spine Syndrome

Hip Osteoarthritis in Patients Undergoing Surgery for Severe Adult Spinal Deformity: Prevalence and Impact on Spine Surgery Outcomes

BACKGROUND

Hip osteoarthritis (OA) is common in patients with adult spinal deformity (ASD). Limited data exist on the prevalence of hip OA in patients with ASD, or on its impact on baseline and postoperative alignment and patient-reported outcome measures (PROMs). Therefore, this paper will assess the prevalence and impact of hip OA on alignment and PROMs.

METHODS

Patients with ASD who underwent L1-pelvis or longer fusions were included. Two independent reviewers graded hip OA with the Kellgren-Lawrence (KL) classification and stratified it by severity into non-severe (KL grade 1 or 2) and severe (KL grade 3 or 4). Radiographic parameters and PROMs were compared among 3 patient groups: Hip-Spine (hip KL grade 3 or 4 bilaterally), Unilateral (UL)-Hip (hip KL grade 3 or 4 unilaterally), or Spine (hip KL grade 1 or 2 bilaterally).

RESULTS

Of 520 patients with ASD who met inclusion criteria for an OA prevalence analysis, 34% (177 of 520) had severe bilateral hip OA and unilateral or bilateral hip arthroplasty had been performed in 8.7% (45 of 520). A subset of 165 patients had all data components and were examined: 68 Hip-Spine, 32 UL-Hip, and 65 Spine. Hip-Spine patients were older (67.9 ± 9.5 years, versus 59.6 ± 10.1 years for Spine and 65.8 ± 7.5 years for UL-Hip; p < 0.001) and had a higher frailty index (4.3 ± 2.6, versus 2.7 ± 2.0 for UL-Hip and 2.9 ± 2.0 for Spine; p < 0.001). At 1 year, the groups had similar lumbar lordosis, yet the Hip-Spine patients had a worse sagittal vertebral axis (SVA) measurement (45.9 ± 45.5 mm, versus 25.1 ± 37.1 mm for UL-Hip and 19.0 ± 39.3 mm for Spine; p = 0.001). Hip-Spine patients also had worse Veterans RAND-12 Physical Component Summary scores at baseline (25.7 ± 9.3, versus 28.7 ± 9.8 for UL-Hip and 31.3 ± 10.5 for Spine; p = 0.005) and 1 year postoperatively (34.5 ± 11.4, versus 40.3 ± 10.4 for UL-Hip and 40.1 ± 10.9 for Spine; p = 0.006).

CONCLUSIONS

This study of operatively treated ASD revealed that 1 in 3 patients had severe hip OA bilaterally. Such patients with severe bilateral hip OA had worse baseline SVA and PROMs that persisted 1 year following ASD surgery, despite correction of lordosis.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surgical Management of Hip-Spine Syndrome: A Systematic Review of the Literature

BACKGROUND

Hip-spine syndrome (HSS) was first described in 1983 to describe the symptomatology resulting from concomitant lumbar degenerative stenosis and hip osteoarthritis. Numerous studies have sought to understand the underlying pathology and appropriate management of this syndrome. The purpose of this article is to review the literature for the specific imaging characteristics and the optimal surgical treatment of HSS.

METHODS

A systematic review was conducted via an electronic database search through PubMed to identify all publications related to HSS. All publications that contained data on patients who underwent surgical treatment for HSS and reported patient-reported outcome measures or radiographic data were included. Exclusion criteria consisted of publications in a language other than English, review articles, and technique articles.

RESULTS

Fifteen articles that focused on the surgical management of HSS were identified. Of these 15 articles, 8 reported radiographic outcomes, with most reporting no significant change in spinopelvic parameters before and after surgery. Thirteen articles reported clinical outcomes, with 8 of those 13 articles identifying patient-reported outcome measures to be significantly improved following surgery.

CONCLUSIONS

The data on the surgical management of HSS remains sparse. While there is some evidence that total hip arthroplasty in patients who previously underwent spinal fusion may have higher complication rates, there remains debate regarding which surgical problem to address first, the hip or the spine.