Total hip arthroplasty for rheumatoid arthritis in younger patients: 2,557 replacements in the Finnish Arthroplasty Register followed for 0–24 years

Background?The results of total hip arthroplasty (THA) in young patients with rheumatoid arthritis (RA) have been reported in only a few studies. On a nationwide level, the outcome of THA in these patients is unknown. We evaluated the population-based survival of THA in patients under 55 years of age with RA and factors affecting the survival.

Patients?Between 1980 and 2003, 2,557 primary THAs performed for RA in patients less than 55 years of age were reported to the Finnish Arthroplasty Register.

Results?Proximally circumferentially porous-coated uncemented stems had a 15-year survival rate of 89% (95% CI 83–94) with aseptic loosening as endpoint. The risk of stem revision due to aseptic loosening was higher with cemented stems than with proximally porouscoated uncemented stems implanted during the same period (RR 2.4; p < 0.001). In contrast, Cox regression analysis showed that the risk of cup revision was significantly higher for all uncemented cup concepts than for all-polyethylene cemented cups with any cup revision as endpoint. There were no significant differences in survival between the THR concepts.

Interpretations?Uncemented proximally circumferentially porous-coated stems and cemented all-poly-ethylene cups are currently the implants of choice for young patients with RA.     

Total hip arthroplasty for rheumatoid arthritis in younger patients: 2,557 replacements in the Finnish Arthroplasty Register followed for 0-24 years

BACKGROUND: The results of total hip arthroplasty (THA) in young patients with rheumatoid arthritis (RA) have been reported in only a few studies. On a nationwide level, the outcome of THA in these patients is unknown. We evaluated the population-based survival of THA in patients under 55 years of age with RA and factors affecting the survival. PATIENTS: Between 1980 and 2003, 2,557 primary THAs performed for RA in patients less than 55 years of age were reported to the Finnish Arthroplasty Register. RESULTS: Proximally circumferentially porous-coated uncemented stems had a 15-year survival rate of 89% (95% CI 83-94) with aseptic loosening as endpoint. The risk of stem revision due to aseptic loosening was higher with cemented stems than with proximally porouscoated uncemented stems implanted during the same period (RR 2.4; p < 0.001). In contrast, Cox regression analysis showed that the risk of cup revision was significantly higher for all uncemented cup concepts than for all-polyethylene cemented cups with any cup revision as endpoint. There were no significant differences in survival between the THR concepts. INTERPRETATIONS: Uncemented proximally circumferentially porous-coated stems and cemented all-poly-ethylene cups are currently the implants of choice for young patients with RA.     

Total hip arthroplasty for primary osteoarthrosis in younger patients in the Finnish arthroplasty register. 4,661 primary replacements followed for 0-22 years

BACKGROUND: Many studies have found a higher risk of revision after hip arthroplasty in younger patients. We evaluated the population-based survival of total hip arthroplasty (THA) in patients under 55 years of age and the factors affecting survival. METHODS: The Finnish Arthroplasty Register was established in 1980, and 74,492 primary THAs were entered into the register between 1980 and 2001. 4,661 of these were evaluated, all of which had been performed for primary osteoarthrosis on patients under 55 years of age. RESULTS: Proximally circumferentially porous-coated uncemented stems implanted between 1991 and 2001 had a 10-year survival rate of 99 (95% CI 98.5-99.6)% with aseptic loosening as endpoint. The risk of stem revision due to aseptic loosening was higher in cemented stems than in proximally porous-coated (RR 5.5, p < 0.001) or HA-coated (RR 6.6, p = 0.01) uncemented stems implanted during the same period. According to Cox regression analysis of cups implanted 1991-2001, the risk of revision for all-polyethylene cemented cups was 3.0 times as high as that for press-fit porous-coated uncemented cups with aseptic loosening as endpoint (p = 0.01). However, when the endpoint was defined as any revision (including exchange of liner), there was no longer any difference between these two concepts, the 10-year survival rates being 94 (92.1-95.5)% for press-fit porous-coated uncemented cups and 93 (88.5-97.6)% for all-polyethylene cemented cups (p = 0.9). INTERPRETATION: Modern uncemented stems seem to have better resistance to aseptic loosening than cemented stems in younger patients. Thus, for younger patients, uncemented proximally circumferentially porous- and HA-coated stems are the implants of choice. Press-fit porous- and HA-coated uncemented cups may have better endurance against aseptic loosening than cemented cups in younger patients. However, when all revisions (including exchange of liner) are taken into account, the survival of modern uncemented cups is no better than that of all-poly cemented cups.     

The uncemented Bi-Contact total hip arthroplasty

We reviewed a consecutive series of 153 uncemented Bi-Contact (Aesculap, Tuttlingen, Germany) total hip arthroplasties (THAs) in 138 patients who had been followed for at least 5 years (mean, 6.8 years; range, 5-9 years). The Bi-Contact uncemented THA consists of a straight femoral stem made of titanium alloy. The proximal portion of the stem is titanium plasma-sprayed. The cup is press-fit with or without hydroxyapatite coating with a facility for anchoring screws with a snap-fit polyethylene liner. The mean age of the patients was 70.8 years (range, 41-94 years). The mean preoperative Harris hip score of 41 (range, 20-80) improved postoperatively to a mean of 92 (range, 56-96). Three acetabular cups were revised for aseptic loosening, and 1 cup was revised for recurrent dislocation. To date, none of the stems have been revised for aseptic loosening. Radiographic evaluation of the remaining 149 hips revealed that the acetabular cup was stable in 146 hips and possibly unstable in the remaining 3 cases with nonprogressive osteolysis behind the cup. None of the stems showed any evidence of instability. Using the recommendation of revision as the endpoint, the cumulative survival for the prosthesis was 97.3% at a mean follow-up of 6.8 years (95% confidence interval, 95.9-99.4), with stem survival of 100%. In the medium-term, these results are comparable to cemented primary THA and justify the continued use of this prosthesis.     

Total hip arthroplasty in patients less than 40 years old with avascular necrosis of the femoral head. A 5 to 19-year follow-up study

We evaluated 34 total hip arthroplasties (THA) for avascular necrosis of the femoral head in 26 patients who were younger than 40 years at the time of the index operation. The average age at the time of THA was 283 (17-38) years. The mean follow-up was 10.9 (5-19) years. We used 6 cemented and 28 cementless acetabular components and a cemented polished tapered stem in all hips. The mean Charnley modified Merle d' Aubigné Postel score was 8.9 points preoperatively and 16.6 points at final follow-up. Two cemented metal-backed cups were revised because of aseptic loosening at 10 years, one cemented polyethylene cup failed at 12 years and 2 more all polyethylene cups had pending failure. The metal-backed cemented cups and the all polyethylene cups had a longer follow-up than the uncemented cups. Therefore and because of the proven unfavourable long-term outcome of the cemented metal-backed Exeter cup we are not able to draw any firm conclusions regarding the preferred choice between cemented and uncemented cups in this particular group of patients. On the femoral site none of the stems had to be revised. Our results show that a cemented polished tapered femoral component has an excellent survival in primary total hip replacement in young patients with avascular necrosis of the femoral head.     

Total hip arthroplasty in patients with Paget's disease of bone: A systematic review

AIM To investigate the clinical and functional outcomes following total hip arthroplasty(THA) in patients with Paget's disease.METHODS We carried out a systematic review of the literature to determine the functional outcome, complications and revision rates of THA in patients with Paget's disease. Eight studies involving 358 hips were reviewed. The mean age was 70.4 years and follow-up was 8.3 years. There were 247 cemented THAs(69%), 105 uncemented THAs(29%) and 6 hybrid THAs(2%). RESULTS All studies reported significant improvement in hip function following THA. There were 19 cases of aseptic loosening(5%) at a mean of 8.6 years. Three cases occurred in the uncemented cohort(3%) at a mean of 15.3 years and 16 cases developed in the cemented group(6%) at a mean of 7.5 years(P = 0.2052). There were 27 revisions in the 358 cases(8%) occurring at a mean of 7 years. Six revisions occurred in the uncemented cohort(6%) at a mean of 8.6 years and 21 in the cemented cohort(9%) at a mean of 6.5 years(P = 0.5117). CONCLUSION The findings support the use of THA in patients with Paget's disease hip arthropathy. The post-operative functional outcome is largely similar to other patients; however, the revision rate is higher with aseptic loosening being the most common reason for revision. Uncemented implants appear to be associated with a lower failure rate, however, there were no modern stem designs fixed using current generation cementing techniques used in the reported studies, and as such, caution is advised when drawing any conclusions.     

Ten-year results with the Morscher press-fit cup: an uncemented, non-modular, porous-coated cup inserted without screws

Total hip arthroplasty (THA) with well designed cementless acetabular implants has shown excellent results. The purpose of this study was to assess our clinical and radiological outcomes using an uncemented cup. We conducted a prospective cohort study including all consecutive primary THAs performed with the Morscher press-fit cup, an uncemented non-modular acetabular component, between March 1996 and December 1998. Patients were evaluated at ten years with clinical and radiological follow-up, patient satisfaction and questionnaire assessment using the Harris hip score (HHS), Merle d’Aubigné and Postel score, the UCLA score, the 12-item short-form health survey (SF-12) and a visual analog scale. Five hundred sixty-one THAs were performed in 518 patients. At 120 months (± 7.3 months), 303 patients with 335 THAs were still available for follow-up. None of the patients had required cup revision for aseptic loosening. At ten years, the cup survivorship was 98.8% (95% CI 97.4–99.5) with cup revision for any cause as an endpoint. No radiolucencies were seen around the cups, but osteolytic defects involved 21 stems (8.3%). Mean total linear polyethylene wear was 0.9 mm. The Morscher acetabular replacement cup provides excellent results at ten years. There were no revisions for aseptic loosening of the cup, and no osteolytic defects were found around the cup. Patient satisfaction was high and the clinical results were very good.     

18 years of results with cemented primary hip prostheses in the Norwegian Arthroplasty Register: Concerns about some newer implants

Background and purpose Few studies have compared the long-term survival of cemented primary total hip arthroplasties (THAs), and several prostheses have been used without adequate knowledge of their endurance. We studied long-term outcome based on data in the Norwegian Arthroplasty Register.Patients and methods The 10 most used prosthesis brands in 62,305 primary Palacos or Simplex cemented THAs reported to the Register from 1987 through 2007 were included. Survival analyses with revision as endpoint (for any cause or for aseptic loosening) were performed using Kaplan-Meier and multiple Cox regression with time-dependent covariates. Revision rate ratios (RRs) were estimated for the follow-up intervals: 0–5, 6–10, and > 10 years.Results 5 prosthesis brands (cup/stem combinations) (Charnley, Exeter, Titan, Spectron/ITH, Link IP/Lubinus SP; n = 24,728) were investigated with 0–20 year follow-up (inserted 1987–1997). After 18 years, 11% (95% CI: 10.6–12.1) were revised for any cause and 8.4% (7.7–9.1) for aseptic loosening. Beyond 10 years of follow-up, the Charnley cup had a lower revision rate due to aseptic loosening than Exeter (RR = 1.8) and Spectron (RR = 2.4) cups. For stems, beyond 10 years we did not find statistically significant differences comparing Charnley with Titan, ITH, and SP stems, but the Exeter stem had better results (RR = 0.5). 10 prosthesis brands (9 cups in combination with 6 stems; n = 37,577) were investigated with 0–10 years of follow-up (inserted from 1998 through 2007). The Charnley cup had a lower revision rate due to aseptic loosening than all cups except the IP. Beyond 5 years follow-up, the Reflection All-Poly cup had a 14 times higher revision rate. For stems, beyond 5 years the Spectron-EF (RR = 6.1) and Titan (RR = 5.5) stems had higher revision rates due to aseptic loosening than Charnley. The analyses also showed a marked improvement in Charnley results between the periods 1987–1997 and 1998–2007.Interpretation We observed clinically important differences between cemented prosthesis brands and identified inferior results for previously largely undocumented prostheses, including the commonly used prosthesis combination Reflection All-Poly/Spectron-EF. The results were, however, satisfactory according to international standards.     

Effect of hydroxyapatite coating on risk of revision after primary total hip arthroplasty in younger patients: findings from the Danish Hip Arthroplasty Registry

Background The effect of hydroxyapatite (HA) on implant survival in the medium and long term is uncertain. We studied the effect of HA coating of uncemented implants on the risk of cup and stem revision in primary total hip arthroplasty (THA).

Patients and methods Using the Danish Hip Arthroplasty Registry (DHR), we identified patients less than 70 years old who had undergone uncemented primary THA during 1997-2005. 4,125 HA-coated and 7,737 non-HA-coated cups and 3,158 HA-coated and 4,749 non-HA-coated stems were available for analysis. The mean follow-up time was 3.4 years for cups and 3.2 years for stems. We estimated the relative risk (RR) of revision due to aseptic loosening or any cause, and adjusted for possible confounders (age, sex, fixation of opposite implant part, and diagnosis for primary THA) using multivariate Cox regression analysis.

Results The adjusted RRs for revision of HA-coated cups and stems due to aseptic loosening were 0.89 (95%CI: 0.37-2.2) and 0.71 (95%CI: 0.27-1.9) with up to 9 years of follow-up, compared to non-HA-coated implants. When taking all causes of revision into consideration, the risk estimates were 0.85 (95%CI: 0.68-1.1) and 0.81 (95%CI: 0.61-1.1) for HA-coated cups and stems, respectively.

Interpretation In this medium-term follow-up study, the use of HA-coated implants was not associated with any clearly reduced overall risk of revision compared to non-HA-coated implants.     

Ten-year results of uncemented hip stems for failed intertrochanteric osteotomy

Introduction Inferior survival of cemented total hip arthroplasty has been reported after previous femoral osteotomy. The purpose of this study was to evaluate the long-term survival of uncemented stems after femoral osteotomy.Materials and methods Forty-eight hips in 45 patients had undergone conversion THA for a failed intertrochanteric osteotomy of the hip after a mean of 12 years (2–33 years). Mean time of follow-up was 11 years (5–15 years).Results At follow-up, two patients (three hips) had died, and one patient (one hip) was not located. Three patients (three hips) underwent femoral revision—one for infection and two for aseptic loosening of the stem. Survival of the stem was 94% at 10 years, and survival with femoral revision for aseptic loosening as an end point was 96%. The median Harris Hip Score at follow-up was 80 points. Radiolucent lines in Gruen zones 1 and 7 were present in 14 and 18% of hips, respectively. Radiolucencies in other zones were not detected. There was no radiographic evidence of femoral osteolysis, stress-shielding or loosening.Conclusion The results with this type of uncemented tapered titanium femoral component after proximal femoral osteotomy are encouraging and compare to those achieved in patients with regular femoral anatomy.     

Cause-Specific Stem Revision Risk in Primary Total Hip Arthroplasty Using Cemented vs Cementless Femoral Stem Fixation in a US Cohort

BackgroundWe sought to evaluate the cause-specific revision risk following hybrid (cemented stem mated to a cementless acetabular implant) vs cementless total hip arthroplasty (THA) in a US cohort.MethodsPrimary elective THA for osteoarthritis was identified using Kaiser Permanente’s Total Joint Replacement Registry (2001-2018). Multivariable Cox regression was used to evaluate cause-specific revision, including aseptic loosening, infection, instability, and periprosthetic fracture (PPF), for hybrid vs cementless THA. Analysis was stratified by age (<65, 65-74, and ≥75 years) and gender.ResultsThe study cohort comprised 88,830 THAs, including 4539 (5.1%) hybrid THAs. In stratified analysis, hybrid THA had a higher revision risk for loosening in females in all 3 age subgroups. A lower risk of revision for PPF was observed following hybrid THA in females aged ≥75 years. For females ≥75 years, cementless THA had an excess PPF risk of 0.9% while hybrid THA had an excess loosening risk of 0.2%, translating to a theoretical prevention of 10 PPF revisions but a price of 3 loosening revisions per 1000 hybrid THAs. No difference in revision risk was observed in males.ConclusionWe observed differences in cause-specific revision risks by method of stem fixation which depended upon patient age and gender. Although the trend toward all cementless fixation continue, there may be a role for hybrid fixation in females ≥75 years to mitigate risk for revision due to PPF at the potential cost of a slight increase in longer term aseptic loosening.Level of EvidenceLevel III.     

Medium-term result of Elite Plus hip arthroplasty: the second modular evolution of the original Charnley low-friction arthroplasty

BackgroundThe Elite Plus total hip arthroplasty (THA) system was introduced as the second modular evolution of the original Charnley low-friction arthroplasty. However, the results of the Elite Plus THA are currently considered to be inconsistent. The aim of this study was to clarify the medium-term results and the factors affecting the results of Elite Plus THA.MethodsThe results of 97 Elite Plus THAs in 87 patients at 5 years or more postoperatively were reviewed. The patients’ mean age was 65 years, and follow-up averaged 8.0 years. The Elite Plus stem was used in all hips, and three designs of socket, Hylamer Ogee in 40 hips, Wroblewski Offset Bore in 38, and Charnley Ogee in 19, were implanted. The survival rates with loosening and revision as endpoints were analyzed. To clarify the risk factors affecting the survival rates, Charnley’s functional classification, Bombelli’s classification, Crowe’s classification, structural bone grafting of the acetabulum, cup design, stem position, and grading of the cement mantle were evaluated.ResultsThe stem survival rate with aseptic loosening as the endpoint was 96 %, and the rate with revision was 100 %. The cup survival rate with aseptic loosening as the endpoint was 80 %, and the rate with revision was 93 %. Using a Cox proportional hazards model, cup design was a potential confounding factor for acetabular loosening (p = 0.001). The loosening rates were 31 % for Hylamer Ogee sockets at 9.4 years, 8 % for Wroblewski Offset Bore sockets at 7.4 years, and 0 % for Charnley Ogee sockets at 5.6 years. No factors were significantly related to acetabular revision and femoral loosening.ConclusionsThe results of Elite Plus stem THA were excellent in the medium term. The cup design was a potential confounding factor for acetabular loosening, and the Hylamer Ogee socket was associated with a poor result.     

Is reverse hybrid hip replacement the solution?: 3,963 primary hip replacements with cemented cup and uncemented stem,from the Norwegian Arthroplasty Register

Background and purpose

Reverse hybrid hip replacement uses a cemented all-polyethylene cup and an uncemented stem. Despite increasing use of this method in Scandinavia, there has been very little documentation of results. We have therefore analyzed the results from the Norwegian Arthroplasty Register (NAR), with up to 10 years of follow-up.

Patients and methods

The NAR has been collecting data on total hip replacement (THR) since 1987. Reverse hybrid hip replacements were used mainly from 2000. We extracted data on reverse hybrid THR from this year onward until December 31, 2009, and compared the results with those from cemented implants over the same period. Specific cup/stem combinations involving 100 cases or more were selected. In addition, only combinations that were taken into use in 2005 or earlier were included. 3,963 operations in 3,630 patients were included. We used the Kaplan-Meier method and Cox regression analysis for estimation of prosthesis survival and relative risk of revision. The main endpoint was revision for any cause, but we also performed specific analyses on different reasons for revision.

Results

We found equal survival to that from cemented THR at 5 years (cemented: 97.0% (95% CI: 96.8–97.2); reverse hybrid: 96.7% (96.0–97.4)) and at 7 years (cemented: 96.0% (95.7–96.2); reverse hybrid: 95.6% (94.4–96.7)). Adjusted relative risk of revision of the reverse hybrids was 1.1 (0.9–1.4). In patients under 60 years of age, we found similar survival of the 2 groups at 5 and 7 years, with an adjusted relative risk of revision of reverse hybrids of 0.9 (0.6–1.3) compared to cemented implants.

Interpretation

With a follow-up of up to 10 years, reverse hybrid THRs performed well, and similarly to all-cemented THRs from the same time period. The reverse hybrid method might therefore be an alternative to all-cemented THR. Longer follow-up time is needed to evaluate whether reverse hybrid hip replacement has any advantages over all-cemented THR.The reverse hybrid method (also known as “inverse hybrid”) uses a cemented all-polyethylene cup in combination with an uncemented stem. This method is partly based on good clinical results of cemented cups and of some uncemented stems in the Norwegian Arthroplasty Register (NAR) (Havelin et al. 2000a,b, Hallan et al. 2007). The register has also shown that some uncemented femoral stems may have better long–term results (> 10 years) than cemented stems in patients 60 years of age or younger. Based on these findings, the NAR suggested 10 years ago that the use of cemented cups in combination with uncemented stems might be justified in young patients (Havelin et al. 2000a). In the Swedish Hip Arthroplasty Register, the performance of uncemented THR was found to be inferior to that of cemented THR (Hailer et al. 2010). The authors of that study found that cemented cups performed better than uncemented cups and that uncemented femoral stems had better survival than cemented stems, with aseptic loosening as endpoint. In the Finnish Arthroplasty Registry, Mäkelä et al. (2010) found better long-term survival regarding aseptic loosening for the best performing types of cementless stems compared to the cemented reference group, in the age group 55–74 years.McNally et al. (2000) studied survival of the Furlong HA coated femoral stem in combination with a cemented ultra-high-density polyethylene cup at 10–11 years, and found values of 99% for the stem and 95% for the cup. Alho et al. (2000) reported results with cemented Lubinus cups and uncemented Furlong stems, and they also pointed out the possibility of using the principle of reverse hybrid arthroplasty. We are not aware of any other reports on the reverse hybrid method.In a reverse hybrid THR, an uncemented stem and a modular head are most often combined with a cemented cup of another name or from another company. Combining implants that are not designed to fit each other might theoretically lead to unexpected complications such as increased wear, loosening, or dislocation. This concern was raised by the NAR already in their report from 2005 (Norwegian Arthroplasty Register 2005). As the use of reverse hybrids is increasing, we decided to evaluate the short- to medium-term results with this concept and to compare them with those from all-cemented THRs, using data from the NAR.     

Survival of Hydroxyapatite-Coated Versus Non-hydroxyapatite-Coated Total Hip Arthroplasty Implants in a Veteran Population

BackgroundHydroxyapatite (HA) coatings were introduced to improve uncemented implant osteointegration and to prevent loosening and osteolysis. However, data regarding these implants have been inconsistent. We studied the effect of HA coating of femoral stems and acetabular cups on component revision after primary total hip arthroplasty (THA) in the veteran population.MethodsWe identified patients who underwent uncemented primary THA at any Veterans Health Administration (VHA) hospital from 2000 to 2017 and who had implants that were available as either HA-coated or non–HA-coated models. The endpoint was removal of the component of interest for any reason. For each individual stem and shell, unadjusted and adjusted (for age and body mass index) Cox proportional hazards models were used to estimate hazard ratios for the risk of explantation between HA-coated and non–HA-coated implants of the same type.ResultsA total of 262 HA-coated cups, 4580 non–HA-coated cups, 4767 HA-coated stems, and 9397 non–HA-coated stems were available for analysis. The mean follow-up time was 9.01 years (43,627 total implant-years) for cups and 7.13 years (101,004 total implant-years) for stems. One of the two shells reviewed had significantly lower survivorship and an elevated hazard ratio for explantation with HA coating. Among the five implant pairs of stems, and the other shell, implant survival and hazard ratios for explantation were not affected by HA coating.ConclusionHA coating did not improve THA implant survival in our veteran population. Although HA-coated versions of hip implants tend to be more costly than their noncoated counterparts, these results do not support their general use.     

Advantages in Using Cemented Polished Tapered Stems When Performing Total Hip Arthroplasty in Very Young Patients

Background

The risk of revision following primary total hip arthroplasty (THA) is increased in young patients who undergo THA for pathologies other than primary osteoarthritis. We report the results of primary THA performed with cemented polished stems in patients aged 40 years and younger for pathologies other than primary osteoarthritis.

Dual-mobility cups in total hip arthroplasty after femoral neck fractures: A retrospective study comparing outcomes between cemented and cementless fixation

IntroductionTotal hip arthroplasty (THA) after femoral neck fracture (FNF) is associated with an increased risk of dislocation. The goals of our study were (1) to determine dislocation and revision rates when dual-mobility cups (DMCs) are used in these patients, (2) to analyze clinical and radiographic outcomes, survivorship, complications and mortality rate, and (3) to compare results between cemented and cementless cups.Patients and methodsWe retrospectively reviewed patients with FNF treated using DMC-THA between 2011 and 2018. A minimum 2-year follow-up was required for clinical and radiographic assessment. The clinical outcome was assessed using the Harris Hip Score (HHS) and Merlé D´Aubigné-Postel score (MDP). Radiolucent lines, osteolysis and cup loosening were analyzed.ResultsWe included 105 patients (105 hips) with a mean age of 75.5 years. There were no dislocations. One patient (1.0%) underwent cup revision at 39 months for aseptic cup loosening. The mean HHS and MDP were 80.5 and 14.2 respectively at a mean follow-up of 4.1 years. A higher MDP was found in patients with cementless rather than cemented cups (15.0 vs. 13.1; p = 0.006). Four patients had radiolucent lines > 1 mm, around cemented cups. At 6.8 years, estimated cup survival was 98.2% for revision for aseptic loosening and 97.3% for revision for any reason. The mortality rates were 6.7% at 1 year and 23.8% at last follow-up.ConclusionOur findings suggest that using DMC in THA for FNF may prevent dislocation with a low revision rate. Cementless cups had a higher MDP than cemented cups.     

Total hip arthroplasty with a cemented, polished, collared femoral stem and a cementless acetabular component. A follow-up study at a minimum of ten years

BACKGROUND: Recent studies have suggested that cemented femoral components with a polished surface may provide superior long-term fixation when compared with femoral components with a roughened surface. The purpose of this study was to evaluate the results of total hip arthroplasty with a cemented femoral component with a polished surface finish and compare them with the results of total hip arthroplasty performed with a similar design of cemented femoral component with a rougher surface finish. METHODS: We retrospectively reviewed a consecutive group of 132 patients (149 hips) in whom primary total hip arthroplasty had been performed by one surgeon using a cemented collared femoral component with a polished (0.1-microm Ra) surface finish and a cementless acetabular component. Ninety-eight patients (115 hips) were followed for a minimum of ten years. We compared the survivorship of this prosthesis with that of a femoral component of similar design but with rougher surfaces (matte or grit-blasted). RESULTS: No polished stems were revised because of aseptic loosening or demonstrated radiographic evidence of loosening; however, eight hips (5.4%) with a polished stem demonstrated osteolysis distal to the greater or lesser tro-chanter. In contrast, six stems (2.0%) with a matte surface finish of 0.8-microm Ra were revised because of aseptic loosening, and an additional five stems were seen to be loose radiographically. Eleven stems (9.2%) with a grit-blasted surface finish of 2.1-microm Ra were revised because of aseptic loosening, and an additional four stems were seen to be loose radiographically. The difference in the prevalence of revision due to aseptic loosening between the group with the 0.1-microm Ra surface and the group with the 2.1-microm Ra surface was significant (p = 0.001), as was the difference between the prevalence of revision due to aseptic loosening between the group with the 0.8-microm Ra surface and the group with the 2.1-microm Ra surface (p = 0.001). No cups were revised because of aseptic loosening, and one hip had radiographic signs of acetabular loosening. CONCLUSIONS: This study demonstrated excellent durability of a prosthesis consisting of a cemented, collared, polished femoral component and a cementless acetabular component. While no hips were revised because of aseptic loosening, distal femoral osteolysis was observed in eight hips (5.4%), a higher prevalence than has been reported by others after similar durations of follow-up of tapered, collarless, polished femoral components.     

Minimum 25-Year Results of a Tapered Titanium Porous Plasma Spray Coated Femoral Component

BackgroundPrevious studies have reported excellent results with tapered, titanium, porous plasma-sprayed components in patients undergoing uncemented primary total hip arthroplasty (THA). The purpose of this study was to examine survival and clinical results at a minimum 25-year follow-up.MethodsWe reviewed all patients who underwent primary THA at our center through 1995 with a specific femoral component that was essentially unchanged since its 1984 introduction, except porous coating was continued circumferentially in 1987, a hydroxyapatite-coated option was offered in 1988, and an offset option was added in 1999. There were 332 patients (396 THA) who had a minimum 25-year follow-up (range, 25 to 37). Mean age at surgery was 48 years (range, 21 to 70 years). Mean follow-up in nonfailed patients was 29 years (range, 25 to 37 years).ResultsThere were 31 femoral revisions (7.8%): 9 infections, 3 failures of ingrowth, 5 aseptic loosening, 8 osteolysis well-fixed, 2 periprosthetic fractures, 2 polyethylene wear with trochanteric avulsion, 1 component breakage, and 1 malalignment well-fixed. Kaplan-Meier survival with the endpoint of all-cause stem revision was 94.8% (95% confidence interval: ±0.9%) at 37 years, and with the endpoint of aseptic loosening/failure of ingrowth was 98.7% (95% confidence interval: ±0.5) at 37 years. Harris hip scores improved significantly from 43 preoperatively to 76 most recently.ConclusionThis tapered, titanium, porous plasma spray-coated femoral component continues to demonstrate high long-term survival with a low rate of femoral component revision for any reason or aseptic loosening/failure of ingrowth.