Association between sagittal spinopelvic alignment and femoral head destruction in the early stage of rapidly destructive coxopathy

Abstract

Aims This study aimed to evaluate sagittal spinopelvic alignment (SSPA) in the early stage of rapidly destructive coxopathy (RDC) compared with hip osteoarthritis (HOA), and to identify risk factors of SSPA for destruction of the femoral head within 12 months after the disease onset. Methods This study enrolled 34 RDC patients with joint space narrowing > 2 mm within 12 months after the onset of hip pain and 25 HOA patients showing femoral head destruction. Sharp angle was measured for acetabular coverage evaluation. Femoral head collapse ratio was calculated for assessment of the extent of femoral head collapse by RDC. The following parameters of SSPA were evaluated using the whole spinopelvic radiograph: pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), sagittal vertical axis (SVA), thoracic kyphosis angle (TK), lumbar lordosis angle (LL), and PI-LL. Results The HOA group showed higher Sharp angles compared with the RDC group. PT and PI-LL were higher in the RDC group than the HOA group. SS and LL were lower in the RDC group than the HOA group. No difference was found in PI, SVA, or TK between the groups. Femoral head collapse ratio was associated with PT, SS, SVA, LL, and PI-LL. A PI-LL > 20° and a PT > 30° correlated with greater extent of femoral head destruction by RDC. From regression analysis, SS and SVA were significantly associated with the femoral head collapse ratio within 12 months after disease onset. Conclusion Compared with HOA, RDC in the early stage correlated with sagittal spinopelvic malalignment. SS and SVA may partially contribute to the extent of femoral head destruction by RDC within 12 months after the onset of hip pain. The present study indicates a potential role of SSPA assessment in identification of RDC patients at risk for subsequent bone destruction. Cite this article: Bone Jt Open 2022;3(1):77–84.

Rapidly Progressive Osteoarthritis of the Hip: A Prospective Study

“…Morphological factors associated with the appearance of RPOH have recently been described by some authors, such as increased pelvic tilt, alteration of lumbar lordosis [13], decreased sacral slope, and spinopelvic mismatch as sagittal spinopelvic malalignment [14] like the increased Tönnis angle, Wiberg angle, or acetabular extrusion index.…”

Osteoporosis, Osteoarthritis, and Subchondral Insufficiency Fracture: Recent Insights

“…Improper pressure induced by these pathological alignments may facilitate the localized accumulation of microdamage, potentially leading to SIFFH and SIFK. The etiology of both SIFK and SIFFH involves subchondral bone fragility [162,172] and distinctive morphological characteristics such as meniscal tears [167], an inverted acetabular labrum [195,196], knee varus alignment [168], hip dysplasia [193], and pelvic tilt [200]. Fragility, morphology, and fracture size accelerate collapse, leading to articular surface deformities.…”

“…Notably, SIFFH can progress to advanced OA or RDC due to femoral head collapse, ultimately necessitating THA [181,182,197]. Older age [178], female sex [174], the location [198] and length [199] of the fracture line as observed on MRI, biomarkers of joint space narrowing [175], pelvic tilt [200], and pelvic range of motion [201] have been identified as risk factors for SIFFH progression. Thus, subchondral bone fragility, fracture severity, and mechanical overload may be involved in SIFFH pathogenesis.…”

Anteroposterior pelvic radiograph findings correlate with sagittal spinopelvic motion

“…Ike et al 2 found that hip motion increases following THA. Onishi et al 18 found that patients with rapidly destructive hip OA and therefore significant bone loss had altered standing sagittal parameters compared to patients without significant bone loss, although they only reported static measurements. Buckland et al 9 studied the effect hip OA on spinopelvic biomechanics.…”