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Biomedical subjects

M A Freeman

Publications and source records attributed to M A Freeman.

At least 109 records · Page 6Linked to original sources
PubMed1987

Presence of macrophages at the bone-cement interface of stable hip arthroplasty components.

The bone cement interface of four clinically stable hip-joint prosthetic components was examined histologically for the presence of macrophages using routine staining and a histochemical technique for acid phosphatase. Macrophages were found in the absence of wear debris in all four cases. Because these cells are capable of bone resorption, their presence at a well-fixed interface must give cause for concern.

Acid Phosphatase↗
PubMed1987

Resurfacing arthroplasty. Femoral head viability.

Although obvious theoretic advantages accrue from resurfacing arthroplasty of the hip, the indications for the procedure are controversial because the failure rate is high and loosening is unacceptably frequent. To determine the role of osteonecrosis in these failures, the viability of bone within the femoral head was determined by histologic examination of bone inside 25 failed femoral resurfacing components. The bone was substantially alive throughout the femoral head in 23 of 25 cases (92%). In two cases, the bone of the femoral head was dead. Both of these hips had clinically failed because of femoral neck fracture. This histologic evaluation indicates that bone death is not an inevitable consequence of femoral head resurfacing and the use of polymethylmethacrylate fixation.

Adult↗
PubMed1987

[Cementless fixation in endoprosthetics].

Prostheses have been fixed to the skeleton with polymethylmethacrylate for some 30 years. Many of these prostheses have failed with time, and failure has been blamed on the use of polymethylmethacrylate. Methods of fixing endoprostheses without cement have been developed in recent years. It is argued in this paper that the most important precondition for fixation is stable press-fit of the implant. Other methods of supplementary fixation, such as porous ingrowth, have been developed. However, there is little evidence to suggest that this ingrowth improves the immediate clinical result, if it occurs at all.

Biomechanical Phenomena↗
PubMed1986

British contribution to knee arthroplasty.

British surgeons and engineers contributed various types of knee prostheses, including hinged, unconstrained, and semiconstrained prostheses, in the development of total knee arthroplasty. Methods of implant fixation, the place of stems, pegs, the use of special instrumentation, and alignment procedures ensure both intrinsic and extrinsic prosthetic stability.

History, 20th Century↗
PubMed1986

Knee arthroplasty at the London Hospital. 1975-1984.

In the past ten years, three related prostheses (Freeman-Swanson, ICLH, Freeman-Samuelson) have been used at the London Hospital. The new findings reported in this article are the result of cementless fixation of the ICLH prosthesis has not deteriorated with time; the patellofemoral complications and postoperative limitation of movement seen with the ICLH prosthesis has been resolved by the Freeman-Samuelson design; and cementless press-fit fixation of all three components of the Freeman-Samuelson design resulted in a 1.6% (tibial) revision rate in the first four years.

Adult↗
PubMed1985

Cementless acetabular replacement using a pegged polyethylene prosthesis.

Acetabular replacement without cement using three types of pegged polyethylene prostheses was begun as a prospective trial by Morscher (August 1977). Ring (June 1979), and Freeman (January 1980); 1878 hips have been replaced using this technique and are reviewed. Follow-up averaged 2 years (range: 6 months-6 years). Successful pain relief and satisfactory walking ability were present in 97% and adequate flexion in 90%. Radiographic review showed the consistent development of a stable, uniform sclerotic line adjacent to the prosthesis. No component migration could be documented. Ten hips have been revised for obvious femoral loosening, and two acetabula showed slight motion during revision for femoral failure and were revised. Deep infection (0.37%) occurred only in patients not receiving perioperative antibiotics and not operated upon in unidirectional filtered air-flow enclosures. Postmortem histological evaluation of eight hips showed a thin fibrous membrane separating the prosthesis from viable bone. These results are preliminary, but nevertheless at least as good as those in any large series of cemented acetabula with the same follow-up. The advantages of this technique are its reproducible results, low complication rate, limited invasion of the skeleton, and easy revision should failure occur.

Acetabulum↗
PubMed1985

Stemmed revision arthroplasty for aseptic loosening of total knee replacement.

Fifty-three failed knee replacements were revised using minimally constrained implants with smooth uncemented intramedullary stems and metal-backed tibial components. Polymethylmethacrylate was used only to replace lost bone near the surface of the implant. Excluding four knees which had serious postoperative complications, 91% had successful relief of pain, 84% had over 90 degrees of movement and 80% could walk for more than 30 minutes. Review of the radiographs showed that there were no progressive lucencies at the interface between bone and cement, and no subsidence of components or changes in alignment. At the uncemented stem-to-bone interface, thin white lines developed near the metal, and their significance is discussed. This revision technique is an effective treatment for aseptic failure of primary total knee arthroplasty.

Adult↗
PubMed1985

The management of infected total knee replacements.

A review of patients with an infected resurfacing prosthesis is presented. Eight patients with a loose infected prosthesis were treated by a one-stage exchange arthroplasty; six others with a well-fixed infected prosthesis were treated by drainage and antibiotics. All eight treated by exchange arthroplasty remained free of infection as did five of those treated by drainage. In four of these last five patients, the prosthesis was inserted without cement; the possible role of polymethylmethacrylate in the persistence of infection is discussed.

Aged↗
PubMed1985

Total ankle arthroplasty. A long-term review of the London Hospital experience.

We report a retrospective study of 62 total ankle arthroplasties performed between 1972 and 1981. Forty-one of these have been reviewed clinically after an average follow-up of five and a half years; only 13 can be described as satisfactory. The complications encountered in all 62 arthroplasties are detailed, the most significant being superficial wound healing problems, talar collapse, and loosening of the components; 13 prosthetic joints have already been removed and arthrodesis attempted. The management of the complications is discussed. In view of the high complication rate and the generally poor long-term clinical results, we recommend arthrodesis as the treatment of choice for the painful stiff arthritic ankle, regardless of the underlying pathological process.

Adult↗
PubMed1984

[Patellar complications of ICLH knee prosthesis].

Three types of patellar complication following total knee replacement with a Freeman-I.C.L.H. prosthesis have been studied. They are: 1) Pain despite a satisfactory position of the patella. 2) Patella fractures and 3) Lateral displacement. Pain in spite of a satisfactory position of the patella occurred in 15 p. 100 of cases. The incidence of this complication was considerably diminished by the use of a patellar implant. The use of a patellar implant did not result in any specific morbidity. Five fractures of the patella were seen, three of them without displacement. Lateral displacement of the patella were seen in 5 p. 100 of cases resulting in instability of the knee and a higher risk of loosening of the tibial component. The authors propose a new type of patellar implant stabilized by a rail.

Female↗
PubMed1984

The composition of normal and osteoarthritic articular cartilage from human knee joints. With special reference to unicompartmental replacement and osteotomy of the knee.

UNLABELLED: The articular cartilage from nineteen osteoarthritic and fourteen normal control adult human knee joints was analyzed for changes in water content, proteoglycan composition and structure, glycosaminoglycan synthesis rates, and cell content. We found no significant differences between visually intact cartilage from osteoarthritic knee joints and cartilage from control joints for any of the parameters studied. In osteoarthritic specimens in which the cartilage surface was not intact the biochemical changes depended on the degree of fibrillation. Surface-fibrillated specimens had a higher water content in the surface layers but no change in the content or synthesis rate of glycosaminoglycan. Deeply fibrillated cartilage, however, had an increased water content through its full depth, and there was a decrease in both the rate of synthesis and the content of glycosaminoglycans. CLINICAL RELEVANCE: The results of this study suggest that degenerative changes in osteoarthritic knees are focal in origin and that corrective osteotomy or unicompartmental joint replacement might be rational procedures for knees in which the cartilage in all of one compartment is visually intact.

Aged↗
PubMed1983

ICLH surface replacement of the hip. An analysis of the first 10 years.

Clinical experience of the ICLH method of resurfacing the hip now spans 10 years. The first 36 arthroplasties, performed between 1972 and 1974, have been previously reported. This review covers in detail 204 such arthroplasties performed between 1975 and 1979 using a standard operative technique and prosthesis; these hips were consecutive and entirely unselected. Follow-up averaged 3.2 years (range two to six years). Successful hips are comparable to hips successfully replaced with stemmed prostheses. The rates of perioperative complications and failure due to infection, ectopic ossification, fracture of the femoral neck, and dislocation are favourably comparable to rates reported for stemmed total hip arthroplasties. The rate of aseptic loosening (17 per cent) greatly exceeded that found for stemmed total hip arthroplasties. Errors of patient selection, operative technique and prosthetic design have been identified. It is concluded that, although resurfacing arthroplasty of the hip may be an appealing procedure with theoretical advantages in certain instances, patient selection is essential, operative technique is demanding and changes in the design of the prosthesis are required. The procedure is still in evolution and therefore it should not yet be generally employed.

Adult↗
PubMed1983

Why not resurface the patella?

The results of resurfacing or not resurfacing the articular cartilage of the patella were reviewed in 71 knees--47 with rheumatoid arthritis and 24 with osteoarthritis--which had been replaced with the ICLH prosthesis. Two rheumatoid and osteoporotic patellae developed transverse fractures with separation and were excluded from the review. The results showed that resurfacing the patella greatly reduced peripatellar pain with no counter-balancing disadvantage.

Aged↗
PubMed1983

Replacement of the knee in rheumatoid arthritis using the Imperial College London Hospital prosthesis (ICLH) 1977-1979.

The Imperial College London Hospital (ICLH) technique and prosthesis for the total replacement of the knee was evolved over the period 1968 to 1977. The results now reported were obtained at The London Hospital on rheumatoid knees operated upon in the period 1977 to 1979. These knees were reviewed and the results published with a one to 2 year follow-up in 1981. In the present paper this review has been extended to 3 to 5 years. We find that in successfully replaced knees the quality of the clinical result has remained unchanged over the extended period of review. Certain further complications have been encountered which are described. These complications have led us to the conclusion that whereas we previously accepted post-operative alignments between one and 10 degrees of valgus, we should now adjust these limits. We now regard a knee having anything less than 5 degrees of valgus post-operatively as having been incorrectly replaced. The limits of valgus can perhaps be extended to 15 degrees. Experience over the period 1977 to 1980 suggested the possibility of further improvements in both the operative technique and the prosthesis. Accordingly the ICLH prosthesis has now been modified. The modified prosthesis (the Freeman-Samuelson prosthesis) is described in this paper but results with it are not reported.

Adult↗