One-third of patients who undergo surgery for adult spinal deformity (ASD) also suffer from severe osteoarthritis (OA) of the hip, which correlates with poorer spinal alignment and physical functioning, according to a study published in The Journal of Bone & Joint Surgery. The Lippincott portfolio releases this journal in collaboration with Wolters Kluwer.
These discrepancies continue to exist even after the surgical treatment of ASD, as highlighted in new research by Dr. Alan H. Daniels and Dr. Bassel Diebo of Brown University, alongside colleagues from 20 North American spinal surgery centres. They note, “Concomitant hip and spine disease are frequent, presenting ongoing challenges for both joint arthroplasty and spine surgeons.”
The study sheds light on functional outcomes for patients suffering from both ASD and hip OA. Adult spinal deformity encompasses various irregularities in spinal curvature and alignment, often developing from degeneration over time, and is expected to increase with an ageing demographic. For those not responding to non-surgical interventions, spinal realignment surgery might be necessary.
Previous research has frequently observed hip OA in conjunction with ASD. Nevertheless, there is scant information regarding how OA impacts patient characteristics and surgical outcomes for ASD, particularly concerning spinal alignment and patient-reported outcomes like physical function and disability.
Dr. Daniels, Dr. Diebo, and their team analysed the prevalence and outcomes of hip OA among 520 elderly patients undergoing ASD surgery across thirteen centres in the US and Canada. Approximately two-thirds of the patients were female, with an average age of 59. Echoing past findings, 34% of these patients had severe OA affecting both hips.
The study compared the characteristics of ASD patients with and without severe hip OA, including essential patient-reported outcomes. These comparisons were also made during post-operative follow-ups with 165 patients: 68 with severe bilateral hip OA, 32 with severe OA in one hip only, and 65 without severe OA in either hip.
Patients with severe bilateral hip OA were found to be older (average age 68 years) compared to those with unilateral (66 years) and non-severe hip OA (60 years). Additionally, those with severe hip OA exhibited higher levels of frailty according to standard assessments.
Although all groups showed similar corrections in lordosis at the one-year post-operative mark, those with severe hip OA displayed poorer spinal alignment, as evidenced by a radiographic measure called the sagittal vertebral axis (SVA). This difference in SVA was significant both preoperatively and at follow-up.
Moreover, several patient-reported outcomes were notably poorer in patients with severe bilateral hip OA, who reported lower physical functioning both before and after surgery. While overall disability scores did not vary significantly between the groups, severe hip OA was linked to ongoing limitations in activities such as walking, travelling, and climbing stairs, with frailty influencing these functional outcomes.
This study is one of the first to examine both the alignment and functional outcomes of patients with concurrent hip OA at the time of surgery for severe ASD. The findings indicate that patients with severe OA in both hips are typically older, more frail, and suffer from poorer physical functioning and disability scores, even after adjustments for spinal deformity correction.
Dr. Daniels and his coauthors conclude, “Given the complexity of concurrent hip and spine disease and the relatively frail condition of these patients, they require careful evaluation and optimisation perioperatively.” They also emphasise the need for further research to determine how to improve outcomes for this complex patient group.
More information: Diebo, Bassel G. et al, Hip Osteoarthritis in Patients Undergoing Surgery for Severe Adult Spinal Deformity, Journal of Bone and Joint Surgery. DOI: 10.2106/JBJS.23.00818
Journal information: Journal of Bone and Joint Surgery Provided by Wolters Kluwer Health
