Mild degenerative changes of hip cartilage in elderly patients: an available sample representative of early osteoarthritis.
This study investigated the cellular and molecular changes which occur in cartilage from adults with femoral neck fracture (FNF) and osteoarthritis (OA), and explored the similarities in hip cartilage obtained from elderly patients and patients with early OA. Femoral heads were retrieved from 23 female patients undergoing total hip arthroplasty (THA). This group included 7 healthy patients with FNF (hFNF), 8 elderly adults with FNF (eFNF), and 8 elderly patients with hip OA (OA). After high-field MRI T2 mapping, osteochondral plugs were harvested from the weight-bearing area of femoral heads for subsequent macroscopic, histologic, and immunochemical evaluation. Additionally, the contents of cartilage matrix were analyzed, and gene expression was detected. The surface of cartilage from hFNF and eFNF patients appeared smooth, regular, and elastic, whereas it showed irregularities, thinning, and defects in OA patients. Elevated T2 values and decreased accumulation of glycosaminoglycans (GAGs) were detected in cartilage from eFNF patients. Furthermore, type I collagen accumulation was slightly increased and type X collagen concentration was obviously elevated in eFNF patients; however, type II collagen distribution and the contents and anisotropy of collagen fibrils in eFNF patients showed no significant changes. Consistent with histology and immunohistochemical results, aggrecan was downregulated and type X collagen was upregulated, while collagens types I and II showed no significant changes in eFNF patients. The cellular and molecular characteristics of hip cartilage in eFNF patients who showed no symptoms of OA were similar to those in patients with mild OA. Thus, eFNF cartilage can serve as a comparative specimen for use in studies investigating early OA.
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Bo
B
Wei
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Qiangrong
Q
Gu
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Dong
D
Li
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Junwei
J
Yan
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Yang
Y
Guo
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Fengyong
F
Mao
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Yan
Y
Xu
Department of Radiology, Jiangsu Key Laboratory of Molecule Imaging and Functional Imaging, Zhong Da Hospital, Medical School of Southeast University Nanjing, Jiangsu, China.
Fengchao
F
Zang
Department of Orthopedics, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China ; Cartilage Regeneration Center, Nanjing First Hospital, Nanjing Medical University Nanjing, Jiangsu, China.
Liming
L
Wang
D000368:Aged; D000369:Aged, 80 and over; D053674:Aggrecans / Q000032:analysis; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D015415:Biomarkers / Q000032:analysis; D002358:Cartilage, Articular / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D016022:Case-Control Studies; D003094:Collagen / Q000032:analysis; D005260:Female; D005265:Femoral Neck Fractures / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D006025:Glycosaminoglycans / Q000032:analysis; D006621:Hip Joint / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000235:genetics / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D012720:Severity of Illness Index
D053674:Aggrecans; D015415:Biomarkers; D006025:Glycosaminoglycans; D003094:Collagen
Femoral neck fracture; articular cartilage degeneration; available sample; elderly patients; osteoarthritis