Relationship between hip osteoarthritis and degenerative disc disease in Chinese

Abstract

<p>Introduction: Spinopelvic motion has been compared to cogwheel system. We postulate patients with degenerative disc disease (DDD) are more likely to suffer from hip osteoarthritis (OA). The aim of the study was to identify the incidence of hip osteoarthritis in patients with DDD.<br>Methods: This is a retrospective cohort study looking at radiographic features of hip OA in our DDD cohort, an open population recruitment cohort of patients with back pain. Whole spine radiographic measurements include sacral slope (SS), pelvic tilt (PT), L1 to S1 kyphotic angle (L1S1), T5 to T12 lordotic angle (T5T12) and pelvic incidence (PI). Patients with available hip X-rays were included. Hip measurements included narrowing of superior or medial joint space, presence of osteophyte, subchondral sclerosis, subchondral cyst and Kellgren Lawrence grading. Pearson correlation was calculated between components of hip OA with sagittal spinal parameters.<br>Results: A total of 125 patients with available hip X-rays were analysed. Narrowing of superior hip joint space is negatively correlated to L1S1 (r=-0.439, p=0.025) and T5T12 (r=-0.648, p=0.003) respectively. The width of superior hip joint space is positively correlated with PI (r=0.414, p=0.036), while medial hip joint space has a negatively correlated with PI (r= –0.419, p=0.033). Other hip OA parameters did not show statical significant with spinal parameters.<br>Discussion and Conclusion: Joint space narrowing of the hip was more prevalent in patients with worse sagittal spinal parameters due to posterior pelvic tilt with less superior acetabular coverage predisposing to degeneration. This urges the importance of recognition of possibility of hip OA in patients with symptomatic DDD.<br></p>