Ultra high molecular weight polyethylene (UHMWPE) was introduced into clinical practice by Charnley in November 1962 and has remained the standard material for the hip and other total joint arthroplasties. Wear of the UHMWPE cup, although studied from the beginning, did not appear to be a clinical problem although Charnley suspected that this would be so in the long term. A review of the outcome of the Charnley low-friction arthroplasty in patients under the age of 40 years at the time of the operation has shown that the incidence of cup migration was exponentially related to the depth of cup penetration. A prospective study using 22.225 mm alumina ceramic (Al 20 3 ) head articulating with cross linked polyethylene was set up with the initial penetration of 0.2 – 0.4 mm in about 2.5 years with no further penetration. The clinical results mirrored closely the experimental results obtained with the identical set of materials and design. The clinical results have now reached 14 year follow-up and the initial total penetration of 0.2 – 0.4mm has remained unchanged. Review of long term results of the Charnley LFA has shown a mean penetration rate of 0.1 mm/year (0.02 – 0.6). With a mean penetration rate of 0.1 mm/year, the revision rate for cup wear and loosening in patients under the age of 50 at the time of the LFA, and with a follow-up to 32 years, is in the region of 10%. If the penetration rate remained at 0.02 mm/year or less then no cups have been revised for aseptic loosening. Ceramic / UHMWPE articulation is the next stage of evolution of the Charnley LFA. A prospective study using zirconia 22.225 mm head is approaching 7 year follow-up in over 1000 cases

Introduction: We previously reported our results of 98 Charnley Low-Friction Arthroplasty in 76 patients with Paget’s disease of the hip at an average follow-up of 10.4 years. The current report presents the outcome of this procedure at 15 to 30 years. Methods: A total of 98 Charnley low-friction arthroplasties were performed on 76 patients, 27 men (37 hips) and 49 women (61 hips) with an average age of 67.4 years (range 51–79 years). All operations were performed by the trans-trochanteric or antero-lateral approach. Results: When component revision was used as the endpoint, the survivorship of the acetabular component was 93% at 15 years (CI, 81% to 98%), 83% at 20 years (CI, 59% to 93%), 72% at 25 years (CI, 41% to 89%) and 36% at 30 years (CI, 2% to 78%). The survival of the femoral component was 91% at 15 years (CI, 80% to 96%), 84% at 20 years (CI, 60% to 94%), 84% at 25 years (CI, 60% to 94%) and 72% at 30 years (CI, 38% to 89%). The survival of both components was 89% at 15 years (CI, 76% to 95%), 81% at 20 years (CI, 56% to 92%), 81% at 25 years (CI, 56% to 92%) and 81% at 30 years (CI, 56% to 92%). When component failure was used as the endpoint, the survivorship of the acetabular component was 78% at 15 years (CI, 64% to 87%), 66% at 20 years (CI, 48% to 80%), 43% at 25 years (CI, 21% to 62%) and 12% at 30 years (CI, 2% to 32%). The survival of the femoral component was 76% at 15 years (CI, 62% to 85%), 67% at 20 years (CI, 48% to 80%), 47% at 25 years (CI, 25% to 67%) and 7% at 30 years (CI, 1% to 26%). The survival of both components was 74% at 15 years (CI, 59% to 83%), 64% at 20 years (CI, 44% to 78%), 43% at 25 years (CI, 20% to 64%) and 7% at 30 years (CI, 1% to 27%). Discussion and Conclusion: Long term results using Charnley’s Low Friction Arthroplasty achieved in this patient group are comparable to general arthroplasty population. (Previous report: Charnley low-friction arthroplasty for Paget’s disease of the hip. J Arthroplasty. 2000 Feb;15(2):210–9)

Total hip replacement is a successful and reliable procedure for the relief of pain, but the results achieved have been reported to be less successful in younger patients who tend to be relatively more active and place greater demands on prostheses than older patients.

Between 1966 and 1978, 226 Charnley low friction arthroplasties (LFAs) were implanted in young patients with an average age at operation of 31.7 years. Initial results were presented at an average of 19.7 years. We have performed a further retrospective analysis of this cohort at 10 years on from the time of data collection of the original study. Of the original cohort, 112 patients are alive and either under follow-up at our hospital or have been traced to other hospitals. 16 have been lost to follow-up. Mean follow-up was 26.4 years. At the time of final follow-up or death, rate of aseptic loosening of the stem was approximately 80%. Acetabular components proved to be less successful with less than 60% remaining well fixed. Differences in survival were apparent between subgroups with differing original pathology with stem survival greater in those with DDH as opposed to rheumatoid or degenerative arthritis and the opposite being true for socket survival.

This study adds to the available knowledge of the longevity of cemented total hip replacement as performed with unsophisticated cementation techniques and how it may perform in differing patients groups.

Introduction: We present our results of the first 413 Charnley arthroplasties performed by and under the supervision of the senior surgeon, using the posterior approach.

Methods: This is a prospective study of clinical and radiographic outcomes. Four hundred and thirteen hip replacements were performed in 380 patients (215 female and 165 male) between 1992 and 1996. The mean age at the time of primary surgery was 67 years (28 – 91 years).

Results: The primary aetiology in 297 of the hips was osteoarthritis. Eighty-two had rheumatoid arthritis.

Eleven patients (3%) had one or more episodes of dislocation.

There were 22 revisions. Three of the revisions were carried out for infection, and a further 2 for recurrent dislocation. Aseptic loosening was the cause of failure in the remaining 17.

Thirty three patients (36 hips, 9%) could not be traced at the time of the final follow-up. There was significant and maintained improvement in pain and function scores.

One hundred and thirty eight patients (146 hips) had died at the time of the final follow-up.

The best and worst case survivorship figures at 10 years were 93 +/− 2% and 83 +/− 2%, and those at 14 years were 88 +/− 4% and 78 +/− 4%, respectively, with revision for any reason as the end-point.

Discussion: Excellent results for the Charnley hip are possible using the posterior approach and surgeons of varying experience. The results presented compare favourably with the published data and confirm that the Charnley remains the gold-standard for longevity in hip arthroplasty. The newer and more costly implants not only need to reproduce these results but also match the cost effectiveness of this prosthesis.

Introduction and Aims: We present the results of 228 consecutive Charnley low-friction arthroplasties, inserted in 193 patients between July 1972 and December 1976. Unusually for this time, all hips were inserted by the posterior approach without trochanteric osteotomy. Method: All patients were enrolled into a prospective study and pre- and post-operative findings recorded. This series was reviewed in 1985 and once again in 2002. The survivors were scored clinically using the Merle d’Aubigné-Postel score with a mean value of 12. The reason for revision was also recorded and analysed. Results: The pre- and peri-operative findings are similar to contemporary series. Due to our stable population, only two patients were lost to follow-up. Our survivor-ship results show a 10-year survival of 93%, deteriorating to a 30-year survival of 73%. Conclusion: Overall our results are comparable to other studies and really vindicate the choice of approach, which at the time was a source of some controversy

Since wear and loosening of the ultra high molecular weight polyethylene is the one factor limiting the life of the arthroplasty we set out to identify factors associated with either low wear 0.02 mm/year or less, or high wear 0.2 mm/year or more. In a group of 1092 patients, 1434 Charnley low-friction arthroplasties 190 (13.2%) showed low wear while 149 (10.4%) showed high wear. We used Chi square test to assess the significance. The characteristics of the low wear group were: female gender (p=0.042) Rheumatoid arthritis (p= 0.014), Charnley category “C” patients (p=0.03) and varus position of the stem (p=0.003) The use of acetabular cement pressurization (p=0.07) and medialization of the cup (p=0.07) approached significance. In the high wear group there was a predominance of males (p=0.042) with primary arthritis (p=0.006) as the underlying hip pathology, and the stem in valgus position (p=0.023). Rim position of the cup was approaching significance (p=0.07). There was no statistical significance between the two groups for revision for aseptic stem loosening or stem fracture (p= 0.49). There was a highly significant difference (p< 0.0001) between the two groups for revision for wear and aseptic cup loosening: 5.3% against 40%. Changes in the cup geometry are sufficient to explain the increasing incidence with depth of cup penetration. There is much to be gained from the use of low wearing ceramic – ultra high molecular weight combination. Tissue reaction to the plastic particles cannot be the cause of stem loosening

A prospective study of Charnley low friction arthroplasty in patients under the age of 51 at the time of surgery. 1092 patients, 668 women and 424 men, mean age 41 years (12–51) at the time of surgery had 1434 Charnley low-friction arthroplasties carried out between November 1962 and December 1990. At mean follow-up 14.2 years (1 – 32), 742 patients (973 hips) are still attending and patients’ satisfaction with the outcome is 96.2%. Survivorship was 95.24% at 10 years and 58.67% at 27 years. Patients who had had previous hip surgery had revision rate 24.8% compared with 14.1%. Patients with rheumatoid arthritis had fewer revisions than those with developmental hip dysplasia or primary osteoarthritis. Large 43 mm diameter cup gave lower revisions for aseptic cup loosening as compared with 40mm cup. Presence and preservation of subchondral plate, rim support compared to medialization of the cup, use of acetabular cement pressurizer and the reduced diameter neck (10mm) all made a contribution to reducing the incidence of revisions for aseptic cup loosening. Closing the medullary canal with bone block reduced the incidence of aseptic stem loosening. Use of the brace reamers did not affect the outcome and there appears to have been no advantage with the flanged stem. The long-term problem was the increasing incidence of revisions for aseptic cup loosening. This was exponentially related to the depth of cup penetration by the head of the femoral component. The long term clinical results of the Charnley LFA remain excellent even in young patients. Rim support of the cup, preservation of the subchondral bone of the acetabulum, cup flange and pressurising of the acetabular cement all make a significant contribution. Distal closure of the medullary canal and central position of the stem are of benefit, but reaming the medullary canal to cortex must be avoided. The long-term problem has been highlighted again as: wear and cup loosening

Purpose of the study: Long-term outcome of Charnley low-friction arthroplasty in young active patients is impaired worldwide due to wear of the polyethylene (PE) component and osteolysis. In the late eighties, reports of possible low wear with some former metal on metal total hip arthroplasties led to the reintroduction of metallic bearings. The aims of this work were to examine the rationale for using metal on metal bearings in primary total hip arthroplasty (THA) and report preliminary results obtained with cementless Metasul™-Alloclassic™ hips. Materials and methods: From January 1994 to March 1997, 64 cementless primary Alloclassic-THA (grit-blasted titanium SL stems and CSF treaded cups) with 28 mm Metasul bearings were performed. Mean age at surgery was 60 years (range, 36–73). Diagnoses were usual, mainly primary osteoarthrosis in 70 p. 100 of the hips. Two bearing surfaces were exchanged for late dislocation at 2.6 and 2.9 years. Thus, 62 hips in 58 active patients (4 bilateral) were reviewed after a minimum 2-year follow-up (mean 3.2 years, range 24–66 months). Results: Clinical results according to the Merle d’Aubigne and Charnley rating system were graded excellent or good in all 62 hips. Radiologically, calcar, atrophy and spot welds were noted in 93 p. 100 and 82 p. 100 of hips respectively. Proximal reactive and lucent lines and mild proximal stress shielding were observed in 8 p. 100 and 4.8 p. 100 of hips respectively. No osteolysis granuloma has thus far been observed in the vicinity of any component. Cobalt blood level remained normal, except in 6 cases due to occupational exposure (n = 1), possible impingement (n = 1) or an unknown cause (n = 4). All elevated cobalt levels (range 7 to 25 mg/l) were nevertheless far below the toxic limit. Discussion: Dislocation may be due either to the posterolateral surgical approach and/or early impingement with the first Metasul bearing design (head sleeve). Metasul acetabular component fixation is not restricted to only cementless metal-backing, unlike alumina-ceramic cups. The concern about the toxicity of metallic wear debris dissemination and the hematocarcinogenic risk must be taken into consideration as for any metallic THA. Follow-up is too short for the new polys for significant comparisons. Conclusion: Metal on metal tribology is well known in vitro and Metasul™ bearings have functioned in vivo for 12 years (120 000 Metasul hips worldwide) as was expected from laboratory tests. Obviously, this friction couple is not the unique answer to PE-wear and THA longevity, but, in light of current data, appears as a trustworthy solution available today