No abstract available.

No abstract available.

We studied the natural history of asymptomatic early avascular necrosis of the femoral head in forty-three patients(forty-three hips) who had been treated with arthroplasty due to progressed avascular necrosis of femoral head but had no symptoms in the other side. All initial lesions were classified with Ficat staging and International classification(ARCO). The duration until symptom onset and radiologic evidence of disease progression were evaluated. The average follow up period was over 37 months. Among forty-three hips, twenty-nine cases(67.4%) remained asymptomatic until last follow up but fourteen cases(32.6%) were symptomatic during the follow up, and twenty-six cases(60.5%) did not progress on the radiography but seventeen cases(39.5%) progressed to Ficat stage 3 or 4. Fifteen cases of IA, IIA, IB-cental and II B-central without lateral lesion did not occur symptom and didnt progress to Ficat stage 3 or 4 over a period of average 47 months(24-71 months). But fourteen cases of IB, IC, g B and II C progressed to Ficat stage 3 or 4 and they were all lateral lesion. These results suggest careful observation only can be done in the case of small involvement(less than 15%) and medial or central lesion relatively over a long period of time but for the large involvement(more than 30%) and especially lateral lesion, aggressive surgical treatment may be considered even though the early stage of disease for the prevention of progression. However it will need more period of time to accurately compare the results of various methods of treatment.
Arthroplasty ; Disease Progression ; Follow-Up Studies ; Head* ; Hip ; Natural History* ; Necrosis* ; Radiography

The purpose of this study was to investigate the gaps of bone-acetabular component interface, the initial mechanical stability and the effects of adjuvant screw fixation in the press-fitted two different shaped porous-coated acetabular components. Semi-hemispherical Harris-Galante II cup and full hemispherical Trilogy cup were press-fitted with or without adjuvant screw fixation in 40 bovine femur. The gaps of bone-implant interface were measured in each radiography of all specimen and axial compression tests and rotational stability tests were performed using servohydraulic tension-compression machine. There was significantly smaller gap at polar 1/3 region in the specimen implanted with Trilogy cup. But the adjuvant screw fixation did not affect the amount of gap. There was no significant statistical difference in axial load and rotational stability test in each situations of fixation. This study demonstrates that the initial mechanical stability is not influenced by the shape of semi-hemispherical Harris-Galante II cup and full hemispherical Trilogy cup and also independent of adjuvant screw fixation. But smaller gap of Trilogy cup at the polar 1/3 region indicates the possibility that less amout of wear debris of polyethylene or metal will be deposited and therefore less osteolysis or cup loosening will occur, but this hypothesis should be confirmed by the long-term clinical follow-up.
Acetabulum* ; Arthroplasty, Replacement, Hip* ; Femur ; Follow-Up Studies ; Osteolysis ; Polyethylene ; Radiography

No abstract available.
Humans

No abstract available.
Ankle*

No abstract available.
Femur Neck*

No abstract available.
Free Tissue Flaps* ; Upper Extremity*

The authors reviewed both the clinical and radiographic results of 36 bipolar hemiarthroplasty using the porous-coated Harris-Galante uncemented femoral stem performed for avascular necrosis in 30 patients from January 1985 to June 1992. The average age was about 45.6 years and the average follow-up was fifty-four months. Clinical results by the Harris evaluation method were excellent in 33 cases, good in 2 cases, and fair in 1 case. The radiographic fixation of the femoral stem at final follow-up was bony ingrowth fixation in 31 cases, fibrous ingrowth fixation in 4 cases, and unstable fixation in 1 case. There was neither medial nor superior migration of the bipolar cup of more than two millimeters.
Follow-Up Studies ; Head* ; Hemiarthroplasty* ; Humans ; Necrosis*

No abstract available.