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At least 865 records · Page 48Linked to original sources
PubMed1986

Experience with Charnley low-friction arthroplasty in Japan.

Of 300 hips operated upon from 1972 to 1983, 11 were followed for more than ten years and 107 hips were followed for more than five years. Only two hips had late infection and required Girdlestone resection. One hip with mechanical loosening was revised. The Charnley low-friction arthroplasty components have proved suitable and presented no special difficulties for Japanese people and their lifestyle. In the case of a severely anteverted femoral neck, a fixation of the stem was anteverted up to 30 degrees and sustained in good position. Acetabular dysplasia is a particular problem for Japanese surgeons but can be managed effectively by bone grafting procedures.

Adult↗
PubMed1986

Charnley low-friction arthroplasty of the hip. Long-term results in South Africa.

Long-term results of 98 Charnley low-friction arthroplasties were followed for a period of a mean of 12 years; 98 of 470 operations qualified for this strict long-term study, 78 (79.6%) with excellent results. If excessive medialization of the cup is avoided, socket complications appear to be minimal (4%). The majority of femoral component failures resulted from femoral stem breakage. Only four hips (4.08%) developed loosening of the femoral stem.

Adult↗
PubMed1987

Long-term review of the McGoey-Evans high-friction uncemented total hip arthroplasty.

To assess the long-term clinical results of uncemented total hip arthroplasty with the McGoey-Evans bipolar high-friction hip prosthesis, the authors reviewed the findings in 86 such hip replacements. The minimum patient follow-up was 5 1/2 years (mean 9 years). Overall, satisfactory results were obtained in 46.5% of cases. There were no deep infections. In contrast to the experience with the cemented hip replacements, the authors found that the results were better in men than women and that most of the revisions were done within 5 years of the original operation. Tissue hypersensitivity resulted in implant loosening in only two cases and no harmful systemic effects arose from the use of this uncemented cobalt-chromium prosthesis. Although this particular hip prosthesis is not recommended because of its inferior design, the findings of the study could be useful in the current practice of uncemented hip arthroplasty.

Adolescent↗
PubMed1984

Charnley low-friction arthroplasty for the treatment of hips with late complications of femoral neck fractures.

Two hundred five Charnley low-friction arthroplasties (LFA) were performed in 205 patients for late complications of femoral neck fractures. LFA was an excellent procedure for relieving pain and restoring function with a good range of movement. The deep infection rate was 3.9%. A detailed analysis of the patients with infection showed a high incidence of previous superficial wound infection or positive bacteriologic culture swabs obtained from the wound at the time of LFA.

Aged↗
PubMed1983

Hemiarthroplasty of the hip using a low-friction bipolar endoprosthesis.

A low-friction bipolar endoprosthesis was implanted in 200 patients. The primary indications for the procedure were acute fractures or failed internal fixation of the hip. The prosthesis was also implanted in a smaller series of patients who presented with pathologic lesions of the femoral head and minimal involvement of the acetabulum. Intrahospital results proved the morbidity and mortality rates to be well within acceptable limits for arthroplasty of the hip. Seventy-five patients were followed up during periods of one to eight years (average, 3 years). Sixty-nine patients (92%) with satisfactory results had a mean Harris hip rating score of 87 points. Six patients (8%) scored below 70, indicating a poor result. The biomechanical advantage of the bipolar endoprosthesis is reflected in the low incidence of failures.

Adult↗
PubMed1983

Charnley low-friction arthroplasty in patients with psoriasis.

A retrospective study of 38 patients with established psoriasis treated by 55 Charnley low-friction arthroplasties showed a superficial infection rate of 9.1% and a deep infection rate of 5.5%. All of the operations were carried out in the Charnley clean-air enclosure, without prophylactic antibiotic therapy. The incidence of postoperative sepsis in psoriatic patients was significantly higher than in patients with osteoarthritis (p less than 0.001) and rheumatoid arthritis (p less than 0.05). Hence, prophylactic antibiotic therapy appears beneficial in psoriatic patients.

Adult↗
PubMed1983

Gait patterns in above-knee amputee patients: hydraulic swing control vs constant-friction knee components.

Multiple displacement patterns, stride dimensions, and temporal components during slow, free-speed, and fast walking were compared in the same seven above-knee amputees using prostheses with constant-friction knee components and using hydraulic swing-control knee components. During walking with the hydraulic-type prostheses, the amputees showed a wider range of walking speeds, improvement in the equality of the durations of successive swing and stance phases, and greater uniformity of forward progression. Improvements toward normal were also seen in several of the displacement patterns of the prosthetic limb during walking with the hydraulic knee. Several gait abnormalities persisted with both types of prostheses.

Adult↗
PubMed1981

Iliotibial tract friction syndrome in athletes.

Over a two year period, 52 cases of iliotibial tract friction syndrome (ITFS) in runners were studied (34 males, mean age 30 years; 18 females, mean age 23 years). This represents 5.0% of the total overuse running injuries studied during this period. The purpose of this study was to determine clinical symptoms, etiological factors and appropriate treatment plans. Examination reveals pain on all flexion-extension movements of the knee, focal tenderness directly over the lateral femoral epicondyle and often slight crepitus and/or sharp pain radiating along the tract during a varus stress provocation test with simultaneous fast extension of the knee from a flexion of 45 degrees. The etiology in many cases was multifactorial and included training errors (22 cases), poor footwear and surfaces (4 cases), functional overpronation (47 of 48 cases with abnormal alignment). The treatment protocol consisted of ice massage, local physiotherapy, modified rest and anti-inflammatory medication for initial control of inflammation. Flexibility programmes were initiated as the pain resolved, and, were appropriate, orthotics (42 cases) were used. Evaluation of 48 patients on follow-up showed this treatment protocol to have a 94% success rate. This study illustrates the important role of proper training methods and orthotic foot control in the prevention and care of ITFS.

Adolescent↗
PubMedDate not supplied

Changes in the upper femur after low friction arthroplasty.

In 169 low friction arthroplasties, an extension to 10 years of the radiological appearances, noted at 4 years after acrylic cement had been in the medullary cavity of the femur, there was no grossly visible evidence of deterioration. An increased number of femora showed hypertrophy with normal bone texture. The number showing atrophy remained the same at about 4.8%. Absorption of the medial neck of the femur averaged 5.5 mm over the whole study and was often preceded by small cystic areas. Evidence of demarcation of cement from the endosteal surface of the femur was absent in 66%. When demarcation did occur, in most cases it was confined to the tip or below the midlevel of the stem. In only 2.4% did it reach slightly above the midlevel. No tendency could be found for the radiological appearances of medial femoral neck absorption or cement demarcation to predominate in patients with lower grade levels of function. Improved techniques, by which more perfect fixation between cement and bone in the upper level of the prosthetic stem is achieved, may eliminate instances of loosening and localized bone erosion encountered elsewhere.

Absorption↗
PubMed1995

Low friction arthroplasty at 10 to 20 years. Consequences of plastic wear.

One hundred eighty-seven patients, in whom 224 low friction arthroplasties were done by 1 surgeon from 1972 to 1983, were observed for 10 to 20 years. An attempt was made to reassess each patient annually. Pain, walking, and passive range of motion were graded on a 6-point scale (d'Aubigné and Postel assessment). Active movements, straight leg raising, and abduction against gravity were recorded in degrees. The average scores, based on 224 assessments done preoperatively, 1914 assessments done during the first 10 years, and 590 assessments done during the second 10 years, were as follows: pain--3.28, 5.71, and 5.59 points; walking--3.34, 5.16, and 4.87 points; passive range of motion--3.42, 4.61, and 4.54 points; straight leg raising--40.5 degrees, 60.8 degrees, and 54.9 degrees points; and abduction against gravity--8.8 degrees, 24.3 degrees, and 19.0 degrees points. The percentage of cases with no cement-bone interface demarcation based on > 2000 radiologic observations was as follows: cup Zone I--9.9%, Zone II--26.4%, and Zone III--26.3%; and femoral Zone 1--72.5%, Zone 2--96.7%, Zone 3--94.2%, Zone 4--89.6%, Zone 5--96.7%, Zone 6--96.3%, and Zone 7-72.6%. A relationship was seen between wear of the socket, and cup migration and revision, development of femoral endosteal erosions (significant at 95% confidence level), and femoral prosthesis migration and revision. Ultra high molecular weight polyethylene particles that migrate to the cement-bone interface are believed to be an important cause of loosening and failure in total hip arthroplasty.

Female↗
PubMed1995

Multiple revision for failed Charnley low-friction arthroplasty.

We reviewed 54 patients at a mean follow-up of 4 years 4 months after rerevisions for failure of Charnley low-friction arthroplasty. Rerevision for aseptic loosening in 26 hips was satisfactory; there were no clinical failures and at the latest radiological assessment only one stem and three sockets showed signs of loosening. By contrast, nine of 20 multiple revisions for recurrent dislocation failed, as did five of eight multiple revisions for deep infection. There was radiological evidence of loosening in one stem and nine sockets in the former group and in three stems and five sockets in the latter.

Adult↗
PubMed1994

[Stress analysis on the acetabular side of bipolar hemiarthroplasty by the two-dimensional finite element method incorporating the boundary friction layer].

We compared the biomechanical characteristics of bipolar and unipolar hemiarthroplasty on the proximal migration of the outer head by determining the von Mises stress distribution and acetabular (outer head) displacement with clinical assessment of hemiarthroplasty in 75 patients. This analysis used the two-dimensional finite element method, which incorporated boundary friction layers on both the inner and outer bearings of the prosthesis. Acetabular reaming increased stress within the pelvic bone and migration of the outer head. A combination of the acetabular reaming and bone transplantation increased the stress within the pelvic bone and grafted bone, and caused outer head migration. These findings were supported by clinical results. Although the bipolar endoprosthesis was biomechanically superior to the unipolar endoprosthesis, migration of the outer head still occurred. The bipolar endoprosthesis appeared to be indicated in cases of a femoral neck fracture or of avascular necrosis in the femoral head, but its use in cases of osteoarthritis in the hip required caution.

Acetabulum↗
PubMed1993

Low friction total knee arthroplasty with the alumina ceramic condylar prosthesis.

This paper evaluates the failure and wear properties of the alumina ceramic posterior cruciate condylar total knee prosthesis, and reports the preliminary clinical results of this prosthesis. Thirteen sets of the alumina ceramic prostheses were used for destruction and wear tests. The average ultimate load in the static destruction tests showed 2.63 x 10(4) Newtons in the femoral component, and 1.28 x 10(4) Newtons in the tibial component. The average ultimate energy in the impact destruction tests showed 22.1 Joules in the femoral components, and 20.3 Joules in the tibial components. The wear test demonstrated that the average depth of wear was 0.04 mm in the alumina ceramic prostheses, and 0.20 mm in the Vitallium prostheses. Observation of the UHMWPE wear surface with a scanning electron microscope indicated many deep scratches and a scooped concave lesion in the Vitallium prostheses; there were few deep scratches in the alumina ceramic prostheses. Thirty patients underwent 32 total knee arthroplasties using the alumina ceramic posterior cruciate condylar prosthesis between 1988 and 1990. The results were evaluated as excellent for 59%, good for 28%, fair for 10%, and poor for 3%. Critical roentgenographic review demonstrated no cases of loosening or sinking after arthroplasties using the alumina ceramic prosthesis. Radiolucent lines were observed only in 4 knees (12%) cases. All were observed around the tibial components, but were less than 1 mm in thickness. The frequency of the radiolucent lines is less than that observed in the Vitallium prosthesis at the same followup period. The alumina ceramic posterior cruciate condylar prosthesis may have sufficient durability and excellent wear properties for low friction total knee arthroplasty.

Aluminum Oxide↗
PubMed1993

A 12- to 18-year radiographic follow-up study of Charnley low-friction arthroplasty. The role of the center of rotation.

In a 12- to 18-year radiographic follow-up study of 95 Charnley low-friction total hip arthroplasties (THA), there was a statistically significant correlation between location of the center of rotation of the total hip prosthesis (notably the element horizontal distance cup to tear-drop) and long-term, unfavorable, radiographic signs, such as acetabular and stem demarcation, cup wear, cup migration, subsidence of the stem, and calcar resorption. Small differences, as little as 2 mm, in the placement of the cup in relation to anatomic landmarks were responsible for these findings. A logistical regression analysis showed that the horizontal distance cup to teardrop was the most significant parameter influencing long-term unfavorable radiographic signs of a THA in comparison with the parameters of age, gender, diagnosis, and body-weight.

Acetabulum↗
PubMed1993

Low-friction arthroplasty in severe acetabular dysplasia.

Eighty consecutive low-friction arthroplasties in 64 patients with secondary arthritis due to severe acetabular dysplasia (Crowe grades III and IV) are analyzed. Two groups of patients were considered. In group 1 over 20% of the cup was not covered by the acetabulum and was reconstructed with a femoral head graft (32 cases; in group 2) a femoral head graft was not used because the cup was adequately covered (48 cases). The mean follow-up period was 9.4 years (range, 3-17 years) for group 1 and 8.8 years (range, 3-18 years) for group 2. Early complications were frequent (19%). To study long-term results only 78 hips were assessed since two patients were excluded due to deep infection. In these 78 hips, group 1 patients showed "better" results after 16 years (69.6% good results) than group 2 (nongraft procedures) (52.2%), but these differences were not significant (P > or = .05). Early cup loosening was more frequent in group 2 than in group 1, and good coverage was obtained in 91% of the group 1 cups and in 71% of the group 2 cups (P > or = .05). Acetabular cup loosening was not correlated with acetabular cup position. Bone-grafts appeared consolidated in all cases, but resorption areas were frequently observed. Radiographic stem aseptic loosening appeared in 10 cases, cortical hypertrophy in 7 cases, and endosteal osteolysis in 3 cases. Although limb discrepancy was frequent in both groups (75%), the average discrepancy was 1.7 cm.

Adult↗
PubMedDate not supplied

Ectopic bone formation following low friction arthroplasty of the hip.

Ectopic bone formation after low friction arthroplasty (LFA) occurs nearly three times as often in males as in females and, in significant amounts, in 10 per cent of the total number of patients. The more limited the range of motion preoperatively, the more severe the degree of ectopic bone formation. The diagnosis does not closely relate to ectopic bone formation though the incidence is highest in osteoarthritis. The removal of osteophytes does not increase the incidence of ectopic bone formation. Trochanteric osteotomy in the surgical exposure is not an important cause of ectopic bone formation. A patient with ectopic bone after LFA on one side has a 92 per cent chance of developing it in a subsequent LFA on the opposite side. Systemic factors appear to play a dominant role in the production of ectopic bone.

Adult↗