Revision of the femur component in total hip arthroplasty using impaction bone grafting (IBG) was performed in 140 hips of 136 patients in our hospital. The mean age of the patients at the time of the femoral component revision was 72 years. The median of follow-up time was 80 months. 140 hips were operated with use of YU stem (Yamagata university stem, collared, not polished)104, Exeter stem 2, CPT 2, Restration 5, and others 27.

The length of the stem was a regular stem 114, a long stem 26. The complications related to the revised hip consist of infection 5, dislocation 8, DVT9, fracture during operation 11. Four stems were revised due to infection and two due to loosening.

YU stem is made of titanium alloy with collar, the surface of that stem is not polished and Ra is 0.27 μm. We started to apply IBG in 1994, there were no IBG instrument set and system available such as Exeter, CPT in Japan, so we had used YU stem. However, the result with YU stem was preferable and the implant was stable. Thus, we have been using YU stem. In the process, there have been a number of improvements in IBG instrument and system since we started using them. At first, all medullar cavity is filled with grafted bone up to proximal entry with moderate impaction. Along with guide pin, new medullar canal is made by drilling and insert stem tamper into the space to tighten the layer of impaction, then cement fixation of the stem is performed. This method made the operative time short and operative technique easy.

There are several advantages of IBG technique we used. In revision THA, we can revise the stem with the same length of previous one again and exchange also a long stem to a regular length stem. In addition, the system make it possible to re-construct the case of distal medullar canal excessively filled with bone cement below stem, by digging about around 2 cm distally without need to remove all the cement. Severe bone atrophy and fragile of femur is also reconstructed by IBG.

Impaction bone grafting technique with modified system has great merit to recover bone stock and to obtain implant stability after femoral reconstruction of revision surgery.

MISTKA resulted earlier recovery of ROM, muscle power and shorter incision. But bleeding after operation did not decrease compared with conventional TKA. We compared MISTKA results between several approach mini arthrotomy, mini midvastus and mini subvastus. There were no difference in these series. We thought extramedullary femoral guide may be less invasive than intramedullary femoral guide system.

34 cases were performed by minisubvastus approach. 17 cases were using intramedullary method. 17 cases were using extramedullary method. We compared JOA score, ROM, muscle power, blood examination, X ray, and operation time. Total protein(TP), albumin(alb), prealbumin(prealb), hemoglobin(Hb), total lymphocyte content(TLC) and CRP were examined.

There was no difference in JOA score, ROM and recovery of muscle power. But there were statistically difference in prealbumine at 1 week after operation and TLC at 2 week after operation.

Extramedullary group showed earlier recovery than intramedullary group.

MIS TKA does not discuss about approach but also system of bone cut. Navigation system is very good method but it is very expensive and takes more time at operation. Extramedullary system we developed is simple and low technology method and useful for MISTKA.

Infection has been one of the serious complications after total hip arthroplasty. It forces physical and mental stress to the patients. We have routinely applied two-stage revision for infected replaced hip joint. Cement spacer mold technique has been used for the purpose since 2002. The purpose of this study is to analysis of peri-operative status and functional outcome of the patients underwent the two-stage revision procedure.

Nine joints of the eight patients were included in the study. Seven patients were female and one was male and its average age was 64 years (55–81 years). After removal of implant, antibiotic-loaded cement spacer prosthesis which was made by the cement spacer mold (Biomet, Warsaw, USA), was inserted. The leg length, range of motion of the hip, walking ability and complications between first and second-stage operation were analyzed. The change of leg length after first stage operation compared with prior operation was ranged from −18 mm to +13 mm with an average of 20 mm. Average range of hip flexion was 70°(40–90°). Patients could walk with crutches after first-stage operation. Complications after first stage operation were found in two cases; fracture of femoral cement spacer prosthesis and dislocation of the femoral spacer. There was no case of recurrence of infection.

Clinical assessment of two-stage revision for infected replaced hip joint with cement spacer mold showed favorable functional outcome and a few complications after first-stage operation. It also showed satisfactory short-term outcome after second-stage operation.