Early Clinical Observation Of Different Head Diameter In Ceramic-on-ceramic Total Hip Arthroplasty

Objective:To observe the early clinical efficacy of28mm,32mm and36mm diameter of femoral head in ceramic-on-ceramic total hip arthroplasty.Methods:Weretrospectively analyzed54patients (56hips) for total hip arthroplasty in our hospital from January2011to April2012, of which52patients were followed up and2cases were lost. All patients were divided into3groups by different head diameter, where18patients (18hips) in the28mm group,17patients (18hips) in the32mm group, and17patients (18hips) in the36mm group. There were no statistical significance in terms of differences of general conditions like gender, age, and so on (P>0.05). It was kept consistent on preoperative preparation and postoperative medication of all patients, and all surgical procedures were done by the same surgeon to ensure the consistency of the surgical operation as much as possible. All patients were treated with the biotype ceramic-on-ceramic prosthesis from Depuy Company. The clinical outcome was evaluated by Harris score, and radiographic evaluations were made preoperative and during follow up.Result:The3groups had no significant difference in preoperative total Harris score, pain score, function score and range of motion score (P>0.05). Total Harris score improved from44.7to88.9after operation. All patients’ incisions were healing I after operations, and there was no postoperative complications such as obvious infection, neurovascular injury, DVT or prosthetic dislocation.2patients separately in32mm group and36mm group had squeaking after10months and15months after operation, and they relived by themselves with on other obvious abnormalities. Each Harris score of the3groups was more significant improved as compared with those of the3groups preoperative (P<0.05). X-ray:joint prosthesis were in place, press-fit acetabularliner: in all cases, the bone structure were normal, and there were no osteolysis and periprosthetic radiolucent line in the X-ray; acetabularanteversion and valgus angle were in the normal range; the periprosthetic bone inward ingrowth. Clinical outcome evaluation:excellent (>90) in26hips, accounting for48.1%, good(80-89) in26hips,accounting for48.1%, medium(70-79) in2hips, accounting for3.7%, and the excellent rate was96.2%. The3groups had no significant difference in postoperative total Harris score, pain score and function score (P>0.05). Postoperative range of motion score in the36mm group was improved more significant than that in the28mm group and32mm group (P<0.05)Conclusion:Contemporary ceramic-on-ceramic prosthesis can effectively improve clinical symptoms of severer hip diseases, and significantly improve the patients’ quality of life. At the same time, lager head diameter prosthesis is more effective to improve the postoperative range of motion, and if conditions permit, we suggest that36mm head diameter prosthesis can be the first choice for young patients or elderly patients with the requirement of a high quality of life.