ABSTRACT
[Objective]To report the mid-term results and main points of modular femoral prosthesis in total hip revision surgery for Paprosky type Ⅲ bone defect of the proximal femur.[Method]Nine cases of Paprosky type Ⅲ bone defect of the proximal femur were treated with modular femoral prosthesis MP and ZMR from May 2003 to October 2006.There were 5 males and 4 females with the age range of 39-65 years(mean age 57 years).All the patients were followed up for 8-34 months(mean 19 months).Causes for revision included loosening and osteolysis of primary cemented prosthesis in 7,and coral face prosthesis sterile loosening in 2.The shortest time from the last operation to the revision was 4 years,and the longest was 12 years.There were 5 of type ⅢA and 4 of type ⅢB according to the Paprosky bone defect classification.[Result]The Harris score was 35 points(28-54) before operation and 85(70-90) after operation.Seven patients walked without the help of crutches,one had a mild pain in the thigh and a leg crispation of 2.5 centimeter,and the other having a medium pain in the thigh limping with a crutch.No significant loosening,infection or osteolysis of distal femur was found.One prosthesis sinking 12 mm in 1 case.[Conclusion]Total hip revision surgery for Paprosky type Ⅲ femoral bone defect using modular femoral prosthesis has optimal mid-term results.It offers stabilization both in the initial and late stages.Due to the separation of prosthetic stem from the proximal prosthesis,the implantation is easy to fix.Modular femoral prosthesis,which is benificial to control offset,anteversion angle,and limb length makes the total hip revision surgery simpler and safer.