Establishment and assessment of rat models of glucocorticoid-induced osteonecrosis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To establish the rat models of glucocorticoid-induced osteonecrosis and evaluate the osteonecrosis by high-resolution micro-CT and histomorphology.</p><p><b>METHODS</b>Totally 30 Sprague-Dawley male adult rats (age:12 weeks; body weight:400-450 g) were randomized into two groups:one group received two doses of intraperitoneal injection of lipopolysaccharide (20 μg/kg) at an interval of 24 hours, 24 hours later, the rats received three doses of intramuscular injection of methylprednisolone (40 mg/kg) at an interval of 24 hours; in the control group,the rats received same amount of normal saline. Four weeks later, 5 rats in each group were sacrificed randomly.Eight weeks later, all the remaining rats were sacrificed and the femur specimens were scanned by micro-CT. The trabeculae parameters of the femoral head were calculated. The hematoxylin and eosin staining were performed to calculated the success rate.</p><p><b>RESULTS</b>The incidence of osteonecrosis was 80% in the experimental group. The micro-CT demonstrated broken and cystic degeneration. The quantitative analysis showed that the bone volume/total volume (experimental group:0.55 ± 0.13 vs.</p><p><b>CONTROL GROUP</b>0.68 ± 0.12;P<0.05), bone surface area / bone volume (experimental group:20.45 ± 5.13 vs.</p><p><b>CONTROL GROUP</b>24.00 ± 5.20;P<0.05), and trabeculae number(experimental group: 5.67 ± 0.50 vs.</p><p><b>CONTROL GROUP</b>6.24 ± 0.96; P<0.05) were significantly lower in experimental group than those in control group.</p><p><b>CONCLUSIONS</b>A rat model of glucocorticoid-induced osteonecrosis was successfully established by lipopolysaccharide and methylpredniso- lone. High-resolution micro-CT is useful for the qualitative and quantitative analyses of the morphology and structure of trabeculae, showing good consistence with the histomorphological findings.</p>

Ceramic on Ceramic or Ceramic-on-polyethylene for Total Hip Arthroplasty: A Systemic Review and Meta-analysis of Prospective Randomized Studies / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Wear debris of polyethylene has become a restraining factor of the durability for total hip arthroplasty (THA). Ceramic on ceramic (COC) has better wear resistance while the squeaking sound and prosthesis fracture are of concern. It is still a controversy that bearing couples are better for THA.</p><p><b>METHODS</b>We performed a systematic review of all English articles identified from PubMed (1966-), Embase (1980-) and the Cochrane Library. Clinical outcomes, complications, revision rates, and radiographic outcomes of COC-THA and ceramic on polyethylene (COP)-THA were compared and evaluated.</p><p><b>RESULTS</b>Eight prospective randomized trials enrolling a total of 1508 patients and 1702 THA surgeries were identified. Our results demonstrated the prosthesis fracture and the squeaking sound is significantly higher in COC group and higher wear rate of the COP. Hip function, loosening rate, dislocation rate, revision rate, and the osteolysis rate were comparable between two groups. According to Grading of Recommendations Assessment, Development and Evaluation system assessment, the strength of evidence was high for prosthesis fracture, dislocation, osteolysis, and moderate for radiolucent line or loosening, hip noise, and revision.</p><p><b>CONCLUSIONS</b>Up to now, there is insufficient evidence to identify any clinical advantage of COC compared with COP. Longer follow-up of larger randomized trial is needed to clarify the outcomes.</p>