Preliminary results using Trabecular Metal (TM) acetabular component (made of tantalum) in primary and in revision total hip arthroplasty are encouraging in few published papers in the literature.

Patients and Methods: The outcome and survivorship of a TM revision uncemented acetabular cup were assessed in 85 consecutive patients (Male 48, Female 37, mean age 70,9 years, range 54–92) undergoing revision THA in the time period from 13.5.2004 to 8.6.2006. Years from previous operation to revision arthroplasty was in average of 10,0 years (range 1–23). Acetabular bone defects were assessed using Paprosky grading system. Monoblock TM cup was used in 26 operations(Paprosky grade I=13; grade IIa=1; Grade IIb=6 and Grade IIc=6). Modular revision TM cup was used in 59 operations (Paprosky grade I=7; Grade IIa=5; Grade Ibis=15;Grade IIc=24; Grade IIIa=5 and Grade IIIb=3). 55 allografts (femoral heads) were used to fill bone defects in 39 acetabulums. TM augment was needed in 4 operations. In 17 operations also the femoral component was revised. Seven of these operations were re-revision operations. Full weight-bearing was allowed after 44 operations, partial weight-bearing after 37 operations and no weight-bearing after 4 operations. In four operations, where TM cup was initially tried to use, the fixation was found to be insufficient. Consequently, the method of revision was changed either to plating and TM-cup (Paprosky grade IIIB, n=2) or protection cup-system (Paprosky grade IIc, n=2).

Results: Subjectively, the patients were satisfied with this operation at the follow-up (mean 14 months, range 3–26). 58 (68%) patients were painless and 72 (85%) patients walked without any support. X-ray studies showed good TM-cup fixation into acetabular host bone and bone defect filling in 84 out of 85 cases in this short follow-up.

Complications: 7 dislocations, 1 deep infection and 1 sciatic nerve injury. These complications were concentrated to alcoholic and patients with many other health problems.

Conclusion: TM implant has very good primary fixation properties in host bone. The cup shows reliable ingrowths and defect filling with host bone. Our good short-term results with TM-cup are similar to the few previously published papers. Further clinical investigation is needed to show the durability and functionality of this new prosthetic material.

Aims: The role of unicompartmental knee arthroplasty (UKA) in the treatment of medial knee osteoarthritis (OA) is controversial. The purpose of the study was to analyse our mid-term results of our UKAs operated in 1991–94. Method: Patient þles, the special knee arthroplasty form and radiographs were used to retrospectively analyse the results of 155 UKAs in 142 patients operated for medial knee OA. Results: The mean age of the patients was 66,4 years (39–86), and 65,5% of the patients were women. Good pain relief was reached in all cases with an average ROM of 0–121 degrees at 3 months postoperatively. The operations were complicated by superþcial wound infection in three patients (2,1%), deep vein thrombosis in one patient (0,7%), and limited ROM in one patient (0,7%). The survival rate of UKA was 91,6% at 9,4 years. A total of 13 knees were revised with a total knee prosthesis. Polyethylene wear (n=9), disease progression (n=2), aseptic loosening (n=1) and fracture (n=1) were the indications for the revision. The postoperative period was uneventful in all patients, and mean ROM was 0–108 degrees at 3 months. Conclusion: In our experience, UKA is a procedure with rapid recovery, good knee motion and patient satisfaction for the carefully selected patients in the treatment of medial knee OA. Once failed, UKA is safely revised with a routine TKA

Aims: The aim of this prospective study was to measure changes of bone mineral density (BMD) in the proximal tibia after cemented total knee arthroplasty (TKA) in osteoarthrotic knee joints. Methods: Sixty-nine patients were scanned by dual-energy x-ray absorptiometry (DXA) within a week postoperatively, at 3, 6 and 12 months follow-up. Results:Medial metaphyseal measurement region on interest (ROI) showed a signiþcant decrease in BMD values in preoperatively varus knees joints (p < 0.0005). In preoperatively valgus knees there was a slight non-signiþcant increase in BMD (p=0.184). At the baseline the medial ROI BMD differed from each other signiþcantly in these alignment groups (p= 0.023, independent samples T-test). Alignment correction in the both groups showed bone remodeling towards similar actual BMD values. Finally medial and lateral BMD values were also more similar suggesting that the bone became equally strong on both compartments of metaphysis. We could not trace the effect of increasing AKS score values to the bone remodeling. Conclusions: We suggest that loading effect on bone may be a major profound bone remodeling factor. Its clinical value can not be ignored nor determined by other changes in knee joint status and function. These results conþrm the clinical importance of recreating the proper valgus alignment of the knee joint in TKA operation, which offers possibly better proof for the longevity of the tibial component.

Aim of the study: The aim of the study was to register and þnd out the longterm femoral bone response after insertion of femoral stem with or with-out cement. Materials and methods: Seventeen patients (7 men, 10 women) underwent cemented and 22 patients (14 men, 8 women) uncemented total hip arthroplasty (THA). The mean age in the cemented group was 69 (58–74) years and in the uncemented group 58 (46–68) years. Femoral bone mineral density (BMD) was measured using Lunar DPX or Lunar DPX-IQ densitometry according to zones by Gruen (ROI 1–7). BMD measurements were made preoperatively, and postoperatively over four to 14 days, and at 3, 6, 12, 24, and 36 months after THA. Postoperative BMD changes were calculated using the immediate postoperative BMD value as a reference, the change being expressed as a percent. Results: Peri-prosthetic BMD decreased signiþcantly almost in all ROIs during the þrst three months after both cemented (5–18%) and uncemented (3–14%) THA (p-values < 0.05 to p< 0.001). At the end of the þrst year the most remarkable decrease in BMD was found in the calcar (zone 7) in both groups (cemented 25%; uncemented 23%). Low preoperative bone loss predicted higher periprosthetic bone loss in both groups. From one to three year only small changes in periprosthetic BMD were detected after THA. Conclusions: The present study suggests that postoperative bone loss is equal after uncemented and cemented THA. The bone loss is most pronounced during the þrst six months after THA and mainly associated in proximal femoral bone. After the phase of acute bone loss, further loss is minimal after uncomplicated THA, reßecting merely the normal aging of bone. Patients with poor bone quality at baseline are at higher risk to lose bone around the prosthesis after THA.

Aims: The aims of this prospective study was to elucidate, how the high tibial opening wedge osteotomy (OW-HTO) corrected the varus angle of the lower extremity to the desired valgus angle in arthrotic knee joint, and what are the typical complications concerning this operation method. Methods: Twenty-one patients were operated on by using the operation technique (Puddu 1998) from September 1999 to August 2000. Results: The mean preoperative femoro-tibial varus-angle of the þrst 21 patients was 1.4. degrees, immediate postoperative valgus-angle was 7.1 degrees and at the latest follow-up, the valgus angle was 5.6 degrees, respectively.

In 16 of these 21 patients the healing was uneventful. Five patients sustained complications. Three patients had fracture of the opposite tibial lateral cortex peroperatively. Two of these fractures healed without complication. One of these patients needed total knee arthroplasty later on because of pseudoarthrosis and loss of OW-HTO correction angle at the osteotomy site. Two patients sustained peroperative þssural fracture up to the lateral tibial joint articulation surface. These fractures healed uneventfully. Conclusion: A group of young, active heavy patients sustaining varus gonarthro-sis are candidates for HTO. After promising results of these 21 OW-HTO operations, we have operated 34 more patients. Complication rate has dropped because of better operative experience. However, OW-HTO is a sensitive operation with itñs possible complications. In experienced hands it is reliable and good operation. Also we have to remember, that this operation allow patients to keep their own knee joint with itñs normal kinesiology.