Objective To explore the expressions of bone morphogenetic protein 2 (BMP-2) and runt-related transcription facotr 2 (Runx2) and microarchitecture of trabecular bone periacetabula in adult patients with developmental dysplasia of the hip (DDH). Methods Between March and September 2008, the trabecular bone periacetabulum was collected from 8 patients with DDH who were scheduled for total hip arthroplasty (aged 37-55 years, 3 males and 5 females, trial group) and from 8 patients with avascular necrosis of the femoral head (Ficat stage II) who were scheduled for hip resurfacing arthroplasty (aged 36-55 years, 3 males and 5 females, control group). The expressions of BMP-2 and Runx2 in the trabecular bone were determined by real-time quantitative PCR, and the microarchitecture was observed by micro-CT and the following parameters were determined: bone volume/total volume (BV/TV), connectivity density (Conn.Dens), trabecular number (Tb. N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), and structure model index (SMI). Results The expressions of BMP-2 and Runx2 were significantly lower in trial group than in control group (P lt; 0.05). The micro-CT showed sparse trabecular bone in trial group and dense trabecular bone in control group. BV/TV and Tb.N in trial group were significantly lower than those in control group, and SMI and Tb.Sp in trial group were significantly higher than those in control group (P lt; 0.05); there was no significant difference in Conn.Dens and Tb.Th between 2 groups (P gt; 0.05). Conclusion The trabecular bone is in a low metabolism condition and its microarchitecture is tendency to be osteoporosis trabecualr bone in adult patients with DDH. It may be related with the acetabular component loosening after total hip arthroplasty.
ObjectiveTo analyze the mid-and long-term effectiveness of the 3rd-generation ceramic-on-ceramic (CoC) total hip arthroplasty (THA) in the younger patients. MethodsA retrospective analysis was made on the clinical data of 68 younger patients (73 hips) who accepted the 3rd-generation CoC THA between March 2001 and May 2009. Of 68 cases, 39 was male and 29 was female with the average age of 38.6 years (range, 18-50 years); there were 15 cases (15 hips) of osteonecrosis of the femoral head, 9 cases (9 hips) congenital dysplasia of the hip, 5 cases (8 hips) of ankylosing spondylitis, 10 cases (10 hips) of osteoarthritis of the hip joint, 12 cases (12 hips) of traumatic hip arthritis, 12 cases (12 hips) of femoral neck fracture, 4 cases (6 hips) of rheumatoid hip arthritis, and 1 case (1 hip) of tumor of the femoral neck. The Harris score and University of California Los Angeles (UCLA) score were used to evaluate the hip joint function and activity level respectively. The visual analogue scale (VAS) was used to assess postoperative thigh pain. Radiological signs of osteolysis, loosening, and alumina ceramic related complications were evaluated continuously. And the KaplanMeier survival analysis was used to assess the prosthesis survival. ResultsThe average duration of follow-up was 9.7 years (range, 6-14 years). Sandwich ceramic liners fracture was observed in 3 cases (3 hips), and revision was performed; 1 case had "squeaking" hip because of physical activity. At last follow-up, Harris score and UCLA score were significantly improved when compared with preoperative scores (P<0.05). Bony healing was obtained in all patients, without osteolysis, loosening, and thigh pain. The VAS score was 0. The 5-year and 10-year cumulative survival rates for ceramic fracture revision were 98.6% and 95.9%, and the 5-year and 10-year cumulative survival rates for osteolysis and loosening revision both were 100%. ConclusionThe 3rd-generation CoC prosthesis offer an excellent option for younger patients in THA and the mid-and long-term effectiveness are satisfactory.