We evaluated the outcome of 41 consecutive Charnley low-friction arthroplasties (LFAs) performed by a single surgeon in 28 patients aged ≤ 35 years at operation between 23 and 36 years previously. There were 20 women and eight men with a mean age of 32 years (23 to 35) at surgery. Two patients (three hips) were lost to follow-up at 12 and 17 years post-operatively, respectively, and one patient (one hip) died at 13 years post-operatively. These patients were excluded from the final evaluation. The survival rate of the acetabular components was 92.7% (95% confidence interval (CI) 88.7 to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1% (95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8) at 25 years. The results indicate that the Charnley LFA remains a reasonable choice in the treatment of young patients and can serve for comparison with newer techniques and implants.

Cite this article: Bone Joint J 2013;95-B:1052–6.

We studied survival to 38 years after Charnley low-friction arthroplasty of the hip. We used revision as an end-point, while adopting a policy of regular follow-up and early revision for radiological changes alone if indicated. Between November 1962 and June 2005, 22 066 primary low-friction arthroplasties (17 409 patients) had been performed at Wrightington Hospital by more than 330 surgeons. By June 2006, 1001 (4.5%) hips had been revised and 1490 patients (2662 hips, 12%) had died. At 31 years, where a minimum of 40 hips were still attending follow-up, survival with revision for infection as an endpoint was 95%, for dislocation 98%, for a fractured stem 88.6%, for a loose stem 72.5% and for a loose acetabular component 53.7%. Wear and loosening of the ultra-high-molecular-weight polyethylene acetabular component were the main long-term problems. We conclude that regular follow-up after hip replacement is essential and that all operative findings should be recorded at revision

A retrospective study of 44 diabetic patients who, between them, had 62 Charnley low-friction arthroplasties, showed a superficial-infection rate of 9.7 per cent and a deep-infection rate of 5.6 per cent. All the operations were carried out in the Charnley clear-air enclosure and prophylactic antibiotics were not used. A statistically significant increase in the overall rate of infection was found in diabetic patients when compared with non-diabetic osteoarthritic patients (P less than 0.001) and rheumatoid patients (P less than 0.01). Hence it is suggested that in diabetic patients there may well be a place for prophylactic antibiotics in hip replacement surgery in addition to the use of the clean-air enclosure

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

Between 1983 and 1988 we carried out 45 Charnley low-friction arthroplasties with autografts from the femoral head in 41 patients for developmental dysplasia of the hip. The preoperative radiographs were assessed for the severity of DDH according to the classifications of Crowe et al, Hartofilakidis et al and Sharp. The postoperative and follow-up radiographs were analysed for coverage of the socket by the graft, for loosening and for the outcome of the fixation of the bone graft. Two patients died (two hips) at four and seven years after THR from causes unrelated to the surgery and were excluded from the final radiological analysis. The mean age of the patients at the time of operation was 46 years 3 months. The autograft of the femoral head covered a mean 26% (16 to 35) of the acetabular component. All the grafts united. Some degree of resorption of the bone graft occurred in 27 patients, and always involved the lateral part of the graft, which was beyond the margin of the socket. After a mean follow-up of 11 years there had been no revisions and 38 patients had no pain or only slight discomfort. One socket migrated and four others were fully demarcated. Our findings indicate that the Charnley LFA with an autograft of the femoral head for DDH remains successful at a follow-up of 15 years

Twenty-one cases of the Charnley low-friction arthroplasty were revised because of recurrent or irreducible dislocation. Three main reasons for this revision, usually in combination, were identified: loss of the abductor mechanism due to trochanteric detachment; shortening of the limb due to high placement of the socket or low section of the femoral neck; and malorientation of the components. Sixteen patients had no further problems after revision. One patient had a single dislocation, four had more than one dislocation although they managed to cope with them and did not require a further revision

We report the long-term outcome of 218 Charnley low-friction arthroplasties in 141 patients who were 40 years old or younger at the time of surgery. The minimum follow-up was ten years with a mean of 16 years. The probability of the femoral component surviving 20 years was 86% and of the acetabular component, 84%. The chance that both components would survive for this period was 75%. The pathological diagnosis significantly influenced implant survival. In rheumatoid patients the probability of both components surviving at 20 years was 96% compared with 51% in patients with osteoarthritis. Clinical assessment of 103 patients (166 hips) in whom the arthroplasty was still functioning showed that 94% of hips had minimal pain or none. We conclude that in young patients cemented total hip replacement is a good procedure for those with rheumatoid arthritis but that the results are much less reliable in those with osteoarthritis

Twenty-two high-density polyethylene sockets from Charnley low-friction arthroplasties have been studied. Acrylic casts and shadowgraph techniques were used to measure both the real and radiographic rates of wear; these rates showed a significant correlation. In the sagittal plane, nine of the sockets had worn lateral to a line drawn vertically from the centre of curvature of the socket, 12 had worn medial to that line and only one was worn exactly in the line. In the coronal plane, nine sockets had worn in front of a similar vertical line, two behind that line and 11 had worn exactly in the line. Evidence of impingement of the neck of the stem onto the rim of the socket was found in 14 patients; this is considered to be one of the causes of socket loosening. The obvious solution is to reduce the diameter of the neck of the stem from 12.5 mm to 10 mm; provided that it is made of cold-formed, high nitrogen-content stainless steel, this narrower neck is strong enough not to fracture

A retrospective review of 1542 Charnley low-friction arthroplasties was carried out to compare the incidence of deep infection arising after plain and gentamicin-containing acrylic cement. There was no significant difference between the two series in primary operations, the infection rate being 1.72% and 1.65% respectively. However, in secondary operations (conversions and revisions) the gentamicin-containing cement gave significantly better results--a 0.81% infection rate as compared with 3.46%. All operations were performed in a clean air enclosure using total-body exhaust suits. Radiological diagnosis of deep infection was possible within one year of operation in all cases. Late haematogenous infection occurred in one case and was related to a skin lesion

Between 1981 and 1986 two groups of patients received either Charnley low-friction arthroplasties or the Wrightington Frusto-Conical hip replacement with otherwise identical management before and after operation. There were 260 consecutive replacements in 215 patients in the first group and 260 consecutive procedures in 211 patients in the second. Both components of each design were cemented and featured a 22.25 mm femoral head, but the geometry of the stems differed. Of the patients lost to follow-up, 16 (18 hips) were in the Wrightington series and 24 (36 hips) in the Charnley series, and of those who have died 20 (23 hips) were Wrightington and 14 (16 hips) were Charnley. All surviving patients have been followed up clinically and radiologically or until revision was necessary. The mean length of follow-up for original surviving components in both series was 140 months (120 to 180). Pain, function and movement were measured by the grading system of Merle D’Aubign′e and Postel and showed a marked improvement in both groups. There was little or no pain in 98% of patients in the Wrightington series and 96% in the Charnley series, while 93% and 85%, respectively, were entirely painfree. Trochanteric osteotomy was used in 292 cases overall, with a complication rate of 13% due to wire breakage, trochanteric bursitis or trochanteric detachment, requiring a further operation in 5.8% (17 hips). Heterotopic ossification was seen in 40% of cases in which trochanteric osteotomy had been performed (117 hips) but only 3% (10 hips) had clinically significant changes. After the direct lateral approach heterotopic ossification was seen in 24% (42 hips) with only 2% in class 3 or 4 (4 hips). Femoral osteolysis was more common in the Charnley series, occurring in 7.6% of cases (17 hips) as opposed to 2.1% (5 hips) in the Wrightington series. Ten acetabular and seven femoral components have been revised in the Wrightington series and 16 acetabular and 11 femoral implants in the Charnley series. Survivorship based on revision for aseptic loosening using the Kaplan-Meier technique showed survival of the femoral implant at 5, 10 and 15 years of 100%, 99% and 98%, respectively in the Wrightington and 100%, 99% and 87% in the Charnley series. The survival of the acetabular component at 10, 12 and 15 years respectively, was 100%, 99% and 95% for the Wrightington, and 99%, 98% and 84% for the Charnley. The survival of both the acetabular and femoral components of the Wrightington system at a mean of 11.7 years was better than that of the Charnley system, with a lower incidence of radiological loosening of unrevised components

In order to improve the fixation of the stem in primary Charnley low-friction arthroplasty, the medullary canal was routinely closed off with a cancellous bone block. A prospective study of 611 consecutive arthroplasties were carried out between 1 and 5 1/2 years (average 2 years and 9 months) after operation. There were two cases of radiological loosening of the stem, both of which could have been avoided. Five other patients showed demarcation of the bone-cement junction at the calcar; two of these are considered to be "at risk" of loosening. There was no evidence of radiological loosening of the stem in 604 cases and the method is recommended for routine use in primary total hip arthroplasty

During the years 1971 to 1975, 378 Charnley low-friction arthroplasties of the hip were performed on 278 patients with rheumatoid arthritis. The average age at operation was thirty-nine years. The follow-up time ranged from one to six years (mean two and a half years). Forty per cent of patients were receiving steroids at the time of operation. The most common complications were loosening of the prosthesis (3.4%), perforation of the femoral cortex and fracture. Deep infection occurred in 0.7%, dislocation in 0.7%, and thromboembolic episodes in 1.3%. Ninety-five per cent of patients were free of pain at follow-up compared to 84% who were severely handicapped by pain before operation. In addition, the increased mobility in 98.5% of patients and their improved independence makes hip replacement a recommendable procedure in these patients

We report a prospective study of the use of intramedullary bone blocks to improve the fixation of a matt-finish femoral stem in Charnley low-friction arthroplasties. There were 379 patients (441 hips), but at a minimum follow-up of ten years there were 258 arthroplasties in 221 patients including some which had been revised. The mean age at surgery was 41 years (17 to 51) and the mean follow-up was 13.4 years (1 to 20 including the early revisions). Nine stems (3.5%) had been revised for aseptic loosening, but there were no stem fractures. Survivorship of stems was 99.2% at ten years and 94.35% at 15 and 20 years. We found that the patient’s gender, the position of the stem and the experience of the surgeon all influenced the outcome. Our findings suggest that using our method of stem fixation, follow-up of over 11 years was needed to reveal the effects of endosteal cavitation of the femur, and of over 13 years to assess any divergence between the clinical and the radiological outcomes of stem fixation

Aims

To our knowledge, no study has compared the long-term results of cemented and hybrid total hip arthroplasty (THA) in patients with osteoarthritis (OA) secondary to congenital hip disease (CHD). This is a demanding procedure that may require special techniques and implants. Our aim was to compare the long-term outcome of cemented low-friction arthroplasty (LFA) and hybrid THA performed by one surgeon.

Increasing follow-up identifies the outcome in younger patients who have undergone total hip replacement (THR) and reveals the true potential for survival of the prosthesis. We identified 28 patients (39 THRs) who had undergone cemented Charnley low friction arthroplasty between 1969 and 2001. Their mean age at operation was 17.9 years (12 to 19) and the maximum follow-up was 34 years. Two patients (4 THRs) were lost to follow-up, 13 (16 THRs) were revised at a mean period of 19.1 years (8 to 34) and 13 (19 THRs) continue to attend regular follow-up at a mean of 12.6 years (2.3 to 29). In this surviving group one acetabular component was radiologically loose and all femoral components were secure. In all the patients the diameter of the femoral head was 22.225 mm with Charnley femoral components used in 29 hips and C-stem femoral components in ten. In young patients who require THR the acetabular bone stock is generally a limiting factor for the size of the component. Excellent long-term results can be obtained with a cemented polyethylene acetabular component and a femoral head of small diameter.

We assessed 41 patients with rheumatoid arthritis (47 hips) who had had revision hip arthroplasty, at an average follow-up of 7 years 4 months (2 to 19). The clinical results were excellent or satisfactory in 43 hips. Radiologically, 45 stems were secure. Fifteen sockets (36.6%) were radiologically loose. Three hips required rerevision. Socket failure is the predominant problem in rheumatoid patients after cemented revision arthroplasty.

An experimental evaluation was made of the efficacy of an unflanged cup, an ogee-flanged cup and the Exeter pressuriser in the pressurisation of acetabular cement. Only a very modest injection pressure could be generated through an unflanged socket and even this was readily lost as the socket "bottomed out". The ogee-flanged socket gave a consistently high injection pressure which could be maintained throughout the process of polymerisation. The Exeter pressuriser gave marginally better results. Of the two cements tested, Palacos with gentamicin showed better intrusion than CMW Type 1 cement, but it also allowed greater extrusion once pressure was released. The importance of maintaining a continuous pressure on the cement throughout polymerisation is emphasised.

We reviewed 249 consecutive Charnley primary low-friction arthroplasties in 191 patients performed by one surgeon using a transtrochanteric approach at a minimum follow-up of ten years. Of these, 37 hips in 32 patients showed osteolysis and were compared with 41 hips in 37 matched patients with no osteolysis. We assessed in each case the wear rate, stability of the prosthesis, acetabular angle, socket angle, thickness of the acetabular and femoral cement mantle, canal flare index, femoral score, stem alignment, implant:canal ratio and stem:canal ratio. We found that a high rate of wear, component instability and osteolysis were associated. Osteolysis was three times more common in men than in women. Factors which reduced osteolysis were cement mantles of 6 mm at the acetabulum and of 3 mm in all zones of the femur, a stem:canal ratio of 60% to 70% and an implant:canal ratio of over 99%. The overall incidence of osteolysis was 14.9% but when these technical criteria were met, the incidence was 5.2%. This suggests that careful technique can dramatically reduce the risk of this complication

We studied wear in the ultra-high-molecular-weight polyethylene offset bore socket in 54 hips which had had Charnley low-friction arthroplasty. At an average follow-up of 8.1 years, the mean penetration rate was 0.04 mm per year. Correlation between the depth of socket penetration and the incidence of socket migration was confirmed, but socket migration occurred with lower penetration than had been previously reported