Resurfacing hip arthroplasty. A 3 to 5-year matched pair study of two different implant designs

We compared the 3 to 5 year clinical and radiological results of two different hybrid metal-on-metal resurfacing hip arthroplasty designs in 28 patients who had undergone bilateral hip resurfacing with ReCap implants on one side and BHR implants on the other side. Both hips were compared in each patient, to specifically evaluate the bone response to the cemented femoral component. Post operative function was measured with the Harris Hip Score and University of California at Los Angeles (UCLA) Activity Score, and was excellent in these patients. Mean cup inclination was 43.3 degrees +/- 7 degrees (43.3 degrees +/- 7 degrees for the BHR and 43.4 +/- 6 degrees for the Recap). The inclination angle was greater than 45 degrees in 15 patients: 7 with a BHR, 8 with a Recap; eight patients showed inclination angles greater than 50 degrees (4 patients in each group). All acetabular monoblock cups were well fixed. One patient (1.8%) had radiographs showing bone changes of uncertain significance around the stem of the femoral component. Three percent had femoral bone resorption in the BHR hip and two percent showed bone resorption in the ReCap hip. There was no evidence of migration of the femoral components. The dual energy X-ray absorptiometry (DEXA) scans identified no real reduction in bone density in these resurfacing hip arthroplasties. None of these hips showed any other adverse features. The biological response showed no difference for the two different designs of resurfacing hip arthroplasties.     

Treatment of the young active patient with osteoarthritis of the hip. A five- to seven-year comparison of hybrid total hip arthroplasty and metal-on-metal resurfacing

We compared the five- to seven-year clinical and radiological results of the metal-on-metal Birmingham hip resurfacing with a hybrid total hip arthroplasty in two groups of 54 hips, matched for gender, age, body mass index and activity level. Function was excellent in both groups, as measured by the Oxford hip score, but the Birmingham hip resurfacings had higher University of California at Los Angeles activity scores and better EuroQol quality of life scores. The total hip arthroplasties had a revision or intention-to-revise rate of 8%, and the Birmingham hip resurfacings of 6%. Both groups demonstrated impending failure on surrogate end-points. Of the total hip arthroplasties, 12% had polyethylene wear and osteolysis under observation, and 8% of Birmingham hip resurfacings showed migration of the femoral component. Polyethylene wear was present in 48% of the hybrid hips without osteolysis. Of the femoral components in the Birmingham hip resurfacing group which had not migrated, 66% had radiological changes of unknown significance.     

Results of metal-on-metal hybrid hip resurfacing for Crowe type-I and II developmental dysplasia

BACKGROUND: Modern hip resurfacing implants may increase stability and preserve more bone than conventional total hip arthroplasty. The purpose of this retrospective study was to analyze the mid-term results in a consecutive series of middle-aged patients with developmental dysplasia of the hip treated with hybrid resurfacing joint arthroplasty. METHODS: Metal-on-metal hip resurfacing was performed in fifty-one patients (fifty-nine hips), forty-two of whom were female and nine of whom were male. The average age at the time of surgery was 43.7 years. Radiographic and clinical data were collected at six weeks, at three months, and at yearly follow-up visits. Seven hips had Crowe type-II developmental dysplasia of the hip and fifty-two had type-I. RESULTS: The follow-up period ranged from 4.2 to 9.5 years (average, 6.0 years). Initial stability was achieved in all but three hips. The clinical outcomes, as rated with the University of California at Los Angeles (UCLA) hip score, improved significantly compared with the preoperative ratings. On the average, the pain rating improved from 3.2 to 9.3 points; the score for walking, from 6.0 to 9.7 points; the score for function, from 5.7 to 9.6 points; and the score for activity, from 4.6 to 7.3 points (all p = 0.0001). The mean Short Form-12 (SF-12) mental score increased from 46.6 to 53.5 points, and the mean SF-12 physical score increased from 31.7 to 51.4 points (both p < 0.0001). The mean postoperative Harris hip score was 92.5 points. On the average, the range of flexion improved from 106 degrees to 129.6 degrees ; the abduction-adduction arc, from 41.9 degrees to 76.9 degrees ; and the rotation arc in extension, from 32.1 degrees to 84.8 degrees (all p = 0.0001). Four patients delivered a total of six healthy babies since the time of implantation of the prosthesis. Radiographic analysis showed a decrease in the mean body weight lever arm from 118.5 mm preoperatively to 103.9 mm postoperatively (p = 0.007). There were five femoral failures requiring conversion to a total hip arthroplasty. One hip showed a radiolucency around the metaphyseal femoral stem. There were no complete acetabular radiolucencies, and all sockets remained well fixed. CONCLUSIONS: The mid-term results of metal-on-metal resurfacing in patients with Crowe type-I or II developmental dysplasia of the hip were disappointing with respect to the durability of the femoral component. However, the fixation of the porous-coated acetabular components without adjuvant fixation was excellent despite incomplete lateral acetabular coverage of the socket. More rigorous patient selection and especially meticulous bone preparation are essential to minimize femoral neck fractures and loosening after this procedure.     

Treatment of primary osteoarthritis of the hip. A comparison of total joint and surface replacement arthroplasty

Of 285 total hip arthroplasties (260 patients) performed for primary osteoarthritis during a six-year period, 135 were resurfaced using a Tharies prosthesis (total hip articular replacement with internal eccentric shells) and 150 were treated with the Trapezoidal-28 total hip replacement. From each of these two groups 100 hips (ninety-one patients in the Tharies group and eighty-six in the Trapezoidal-28 group) that had been followed for two to seven years were evaluated at the time of follow-up in accordance with a predetermined protocol. The patients were younger in the Tharies than in the Trapezoidal-28 group (average ages, fifty-eight and sixty-six years), included more men (sixty compared with thirty-five), and were more active postoperatively. The average follow-up was forty-seven months for the total joint-replacement group and thirty-eight months for the surface replacement group. At follow-up the ratings for pain, walking, and function according to the University of California at Los Angeles 10-point scale and the clinical results were identical in the two groups. Heterotopic ossification (Brooker grade III or IV) developed after thirteen Trapezoidal-28 and twenty-two Tharies arthroplasties. Radiographs made at six and twelve months and at final follow-up showed that the incidence of radiolucencies about the acetabular component was higher in the resurfacing group: fifty-seven with complete radiolucent lines after an average follow-up of thirty-eight months compared with thirty-six with complete lines after an average follow-up of forty-seven months. There were three failures in the joint-replacement group: a hematogenous staphylococcal deep infection that required a Girdlestone procedure, a femoral stem fracture that required revision, and loosening of an acetabular component for which revision was performed. There was also one dislocation, successfully treated by closed reduction. Similarly, in the resurfacing group there were three failures: two loose acetabular components, revised successfully, and one loose femoral component that necessitated total joint arthroplasty. Multivariate stepwise regression analysis showed that the factors that affected the final extent and width of the acetabular radiolucencies adversely after resurfacing were: any radiolucent lines that were visible at six months, a high level of physical activity after arthroplasty, and a thin superior cement mantle.(ABSTRACT TRUNCATED AT 400 WORDS)     

Alternative bearing surfaces in total hip arthroplasty: zirconia-alumina pairing. Contribution or caveat?

The aim of the present study was to evaluate the zirconia and alumina articulation in total hip arthroplasty in regard to clinical and radiological outcome. This is the first report concerning the clinical application of a hybrid ceramic articulation. Owing to ethical reasons, a limited number of patients was enrolled in the study. Ten consecutive patients with degenerative arthritis were randomly allocated after informed consent to hybrid total hip arthroplasty treatment using an alumina femoral head and an alumina acetabular liner (5 hips), or using a zirconia femoral head and an alumina acetabular liner (5 hips). The median age of patients at index operation was 57.8 years. Current criteria were used for clinical and radiological assessment. The mean follow-up was 5.1 years (5 to 5.3 years). No hip required revision, and no clinical and radiological differences were observed between the two groups of hips. The median preoperative Harris hip score was rated 55.3 points in the control group of hips with alumina head, and 55.6 in the group of hips with zirconia head. The median Harris hip score increased to 94.9 points at the time of follow-up in the control group, and 96 points in the zirconia group. No radiological signs of cup loosening or focal acetabular osteolysis were detected at follow-up. All stems showed stable fixation without radiolucent lines or focal osteolysis. Zirconia femoral heads and alumina acetabular liners have been successfully used in the present series of 5 total hip arthroplasties with a mean follow-up of 5.1 years. Nevertheless, the use of femoral heads made of zirconia in total hip arthroplasties remains an important clinical concern due to the potential genesis of wear microparticles which can lead to progressive osteolysis. Further in-vitro and in-vivo investigations are required to define the value of this alternative bearing surface.     

Second-generation cementless total hip arthroplasty. Eight to eleven-year results.

BACKGROUND: Second-generation cementless femoral components were designed to provide more reliable ingrowth and to limit distal osteolysis by incorporating circumferential proximal ingrowth surfaces. We examined the eight to eleven-year results of total hip arthroplasty with a cementless, anatomically designed femoral component and a cementless hemispheric acetabular component. METHODS: Ninety-two consecutive primary total hip arthroplasties with implantation of a femoral component with a circumferential proximal porous coating (Anatomic Hip) and a cementless hemispheric porous-coated acetabular component (Harris-Galante II) were performed in eighty-five patients. These patients were prospectively followed clinically and radiographically. Six patients (seven hips) died and five patients (seven hips) were lost to follow-up, leaving seventy-four patients (seventy-eight hips) who had been followed for a mean of ten years (range, eight to eleven years). The mean age at the time of the arthroplasty was fifty-two years. RESULTS: The mean preoperative Harris hip score of 51 points improved to 94 points at the time of final follow-up; 86% of the hips had a good or excellent result. Thigh pain was reported as mild to severe after seven hip arthroplasties. No femoral component was revised for any reason, and none were loose radiographically at the time of the last follow-up. Two hips underwent acetabular revision (one because of dislocation and one because of loosening). Kaplan-Meier survivorship analysis was performed with revision or loosening of any component as the end point. The ten-year survival rate was 96.4% +/- 2.1% for the total hip prosthesis, 100% for the femoral component, and 96.4% +/- 2.1% for the acetabular component. Radiolucencies adjacent to the nonporous portion of the femoral component were seen in sixty-eight (93%) of the -seventy-three hips with complete radiographic follow-up. Femoral osteolysis proximal to the lesser trochanter was noted in four hips (5%). No osteolysis was identified distal to the lesser trochanter. Periacetabular osteolysis was identified in twelve hips (16%). Five patients underwent exchange of the acetabular liner because of polyethylene wear. CONCLUSIONS: This second-generation cementless, anatomically designed femoral component provided excellent clinical and radiographic results with a 100% survival rate at ten years. The circumferential porous coating of this implant improved ingrowth and prevented distal osteolysis at a mean of ten years after the arthroplasty.     

Function and survival after revision of hip resurfacing

The purpose of this study was to compare functional outcome and survival of isolated acetabular, isolated femoral and both component revision after failure of primary Birmingham Hip Resurfacing. The Oswestry Outcome Centre prospectively collected data on 5000 hip resurfacing between 1997 and 2002. Of these, 182 hips were revised: 8% had revision of the acetabular component only, 42% had revision of the femoral component only to conventional stemmed prosthesis, and 50% had revision of both components to conventional total hip arthroplasty (THA). We used a postal questionnaire to assess function by Harris and Merle d'Aubigné and Postel hip scores and determined survival using re-revision as an endpoint. In patients with isolated acetabular revision, the median Harris hip score (HHS) was 74 at a mean of 4.5 years follow up. Isolated femoral revision had a median HHS of 82 at a mean of 3.8 years. When both components were revised, the median HHS was 85 at a mean of 4 years. We observed no difference in HHS between the groups. There was an average survival of 92% at 10 years. Survival was significantly lower for isolated acetabular revision (75%) than isolated femoral (93%) or both component revision (96%).     

Modular cementless total hip arthroplasty for multiple epiphyseal dysplasia

We analyzed a consecutive series of 23 total hip arthroplasties that had been performed using modular cementless prostheses in 13 patients with a confirmed diagnosis of multiple epiphyseal dysplasia and end-stage osteoarthritis of the hip. The average Harris hip score improved from 40.6 to 93.8 points. Postoperatively, all hips demonstrated favorable alterations in the biomechanical parameters including hip center of rotation, femoral offset, femoral neck length, and limb length. At a mean follow-up of 4.8 years, no hip required revision because of aseptic loosening of the acetabular or femoral component. One patient (1 hip, 4.3%) underwent reoperation for polyethylene wear and osteolysis 8 years after index arthroplasty. This study shows encouraging clinical and radiographic outcomes of modular cementless total hip arthroplasties for this technically difficult condition.     

Primary bipolar total hip arthroplasty

A retrospective clinical and radiographic review of 140 primary total hip arthroplasties using a bipolar acetabular component and an uncemented AML femoral component (Depuy, Warsaw, IN) was done. The length of follow-up was from 2 to 5 years with a mean of 44.2 months. A mean postoperative Harris hip score of 84.3 points and a mean postoperative Harris pain score of 38.8 points were identified. Five hips required revision surgery, three for recurrent dislocations and two for infection. Nine percent of acetabular components were noted to have migrated within the bony pelvis by 2 mm or more. However, the presence of migration was not statistically associated with low pain or function scores. Ninety-eight percent of patients with surviving implants felt satisfied with the results of their surgery. Total hip arthroplasty using a bipolar acetabular component appears to be a successful method of hip replacement.     

Hybrid total hip arthroplasty

One hundred twenty-six primary total hip arthroplasties composed of a hybrid cemented femoral component and a cementless acetabular component were followed for a minimum of two years (mean, 42 months). The average patient age was 63 years. The most common diagnosis was osteoarthritis (85 hips), although 13 of the cases were severe or total congenital dislocations. Overall, the results were excellent. The mean Harris hip score was 93. Postoperative pain was rated as none or slight in 94% of the cases. No patient had moderate or severe pain. No femoral or acetabular components were revised. Roentgenographically no femoral component was definitely or probably loose. One acetabular reconstruction component had migrated. The authors conclude that the selective use of cemented and cementless fixation by anatomic site in this hybrid form of hip arthroplasty provided excellent results for five and one-half years.     

Uncemented bipolar double-cup arthroplasty of the hip in inflammatory arthropathy

From 1979 to 1986, 42 uncemented surface arthroplasties were performed in 27 patients with an inflammatory arthropathy of the hip: median age at operation 40 years (range 19-65 ys), median follow-up period 73 months (range 36-120 mo). After 36 months, in 26 of 42 hips, the mean Harris Hip Score was excellent or good (mean 89, range 80-100). In 14 cases, the mean score was fair (76, range 70-79). Overall, those hips with the longest followup period (60-120 m) gradually improved over the years. No correlation was found between the clinical score and radiologic complications such as varus tilting of the femoral component, acetabular protrusion of the cup, or heterotopic ossification. Conversion to a conventional total hip arthroplasty was required in four patients. One patient required a total hip arthroplasty 86 months after the initial operation because of a femoral neck fracture. In two other patients, revision was performed after 60 and 32 months respectively because of a preexistent osteonecrosis and a severe foreign body response to polyethylene debris. Both patients had a varus tilting of the femoral component. In the fourth patient, in whom revision surgery was necessary 28 months after surface replacement there was no explanation for the varus shift of the femoral component. Regarding those problems that can appear after conventional total hip replacement in inflammatory arthropathy, we conclude that the uncemented surface replacement of the hip can be a reasonable alternative.     

The fate of revised uncemented acetabular components in patients with rheumatoid arthritis

The results of patients with rheumatoid arthritis who had revision hip arthroplasty have been studied infrequently. The purpose of this study was to review the authors' clinical and radiographic experiences and outcomes with revision hip arthroplasty. Revision total hip arthroplasties were done on 28 patients (30 hips). All hips had morselized bone grafting and four hips had bulk allografts for segmental defects. The mean age of the patients at the time of surgery was 50 years (range, 20-74 years). Patients were followed up for 4 to 15 years (mean, 7 years). At the latest followup, 14 hips (13 patients) of the 30 hips (47%) had good and excellent Harris hip score ratings. Mechanical failures included six hips (five patients) that had revision arthroplasty and two hips (two patients) that had resection arthroplasty. Six other hips (five patients) had poor Harris hip score ratings. The Kaplan-Meier survivorship curve for failure of the acetabular component revealed an 89% chance of survivorship curve for failure of the acetabular component revealed an 89% chance of survival at 60 months and a 44% chance of survival at 108 months. Based on the results of this study, revision hip arthroplasty for acetabular loosening with a cementless acetabular prosthesis has a low rate of success in patients with rheumatoid arthritis.     

Precoated femoral component in total hip arthroplasty. Results of 5- to 9-year followup.

One hundred nineteen consecutive primary hybrid total hip arthroplasties with a precoated femoral component were performed by one surgeon in 100 patients and followed up prospectively. Ninety-eight hips in 82 patients (mean age, 67 years) were evaluated clinically and radiographically at a mean of 6.5 years (range, 5-9 years). The hips were evaluated clinically using the Harris hip score, and radiographs were evaluated for femoral cement grade, loosening, and osteolysis. Ninety-five hips remained in place at the most recent followup. Two femoral components were revised for definite loosening, and one well fixed femoral component was removed because of late hematogenous infection. Excluding the three hips that were revised, the clinical result was excellent or good in 79 hips (83%), fair in 12 hips (13%), and poor in four hips (4%). All other femoral components were well fixed. There were defects of the cement mantles (C1 and C2) in 90 hips. No femoral component had a stem and cement radiolucent line. Focal femoral osteolysis was seen in only two hips. One acetabular component was removed at 5 years because of late hematogenous infection. One acetabular component had asymptomatic migration. The remaining 96 acetabular components were well fixed. Focal acetabular osteolysis was present in four hips. The mean linear polyethylene wear rate was 0.06 (+/- 0.05) mm per year. In contrast to other reports of early failure and osteolysis, the use of a precoated femoral component in this study did not adversely affect the fixation of hybrid total hip arthroplasty, with definite failure of only 2% (two of 98) of the femoral components.     

Long-Term Outcome of Small Head Metal-On-Metal Total Hip Arthroplasty: A 15-to-22 Year Follow-Up

BackgroundThe Metasul articular interface was a second-generation metal-on-metal (MoM) total hip arthroplasty (THA) that was introduced as a promising interface with improved manufacturing technology, better clearances, and enhanced metal hardness. In December 2001, the manufacturer recalled these implants due to the failure of cup osseointegration.MethodsBetween 1997 and 2004, 168 consecutive primary Metasul THAs were performed in 144 patients. Most patients received a cementless femoral and porous-coated acetabular component with 28 mm head. A competing risk analysis was performed for determination separately for bearing surface-related, recalled bearing failure, and end point revision for any reason. For clinical patient evaluation, we used Harris hip score and University of California at Los Angeles scores. Cobalt and chromium ion level measurement and standard radiographic assessment was performed.ResultsOf the 168 THAs, 19 hips were revised at a mean period of 15 years as follows: 12 of them were due to recalled acetabular component, five hips had noninterface-related complication, and two true interface surface failure. The survival distribution function of all hips with revision for any reason was 88.4%, for bearing interface relation 98.8%, and 92.6% for recalled cups. The mean Harris hip score and University of California at Los Angeles scores were 85 and 6, respectively, and the median Co and Cr blood levels were 1.0 and 0.91 μg/L.ConclusionExcluding the recalled components, Metasul articular interface has performed extremely well at a minimum follow-up of 15 years in this relatively young population. There were two interface-related revisions in the entire cohort.     

Gait analysis of patients with resurfacing hip arthroplasty compared with hip osteoarthritis and standard total hip arthroplasty

Patients with standard total hip arthroplasties may have reduced hip abduction and extension moments when compared with normal nonosteoarthritic hips. In comparison, patients after resurfacing total hip arthroplasty appear to have a near-normal gait. The authors evaluated temporal-spatial parameters, hip kinematics, and kinetics in hip resurfacing patients compared with patients with unilateral osteoarthritic hips and unilateral standard total hip arthroplasties. Patients with resurfacing walked faster (average 1.26 m/s) and were comparable with normals. There were no significant differences in hip abductor and extensor moments of patients with resurfacing compared with patients in the standard hip arthroplasty group. This study showed more normal hip kinematics and functionality in resurfacing hip arthroplasty, which may be due to the large femoral head.     

A randomised study comparing resection of acetabular bone at resurfacing and total hip replacement

We have undertaken a prospective, randomised study to compare conservation of acetabular bone after total hip replacement and resurfacing arthroplasty of the hip. We randomly assigned 210 hips to one of the two treatment groups. Uncemented, press-fit acetabular components were used for both. No significant difference was found in the mean diameter of acetabular implant inserted in the groups (54.74 mm for total hip replacement and 54.90 mm for resurfacing arthroplasty). In seven resurfacing procedures (6.8%), the surgeon used a larger size of component in order to match the corresponding diameter of the femoral component. With resurfacing arthroplasty, conservation of bone is clearly advantageous on the femoral side. Our study has shown that, with a specific design of acetabular implant and by following a careful surgical technique, removal of bone on the acetabular side is comparable with that of total hip replacement.     

Femoral component neck fracture after failed hip resurfacing arthroplasty

Failure on the femoral side after third-generation metal-on-metal hip resurfacing arthroplasty is suggested to be easily treated with conversion to conventional total hip arthroplasty. Clinical results of conversion for failed hip resurfacing arthroplasty with the use of primary femoral implants confirmed this for a short-term follow-up. We present a case of the occurrence of a stemmed femoral implant neck fracture in a patient who was earlier treated for a failed hip resurfacing. We advise to consider acetabular revision in case of (suspected) acetabular metal damage and to use a stem component with a relative large neck diameter.     

The five-year results of the Birmingham Hip Resurfacing arthroplasty: an independent series

Few independent studies have reported the outcome of resurfacing arthroplasty of the hip. The aim of this study was to report the five-year clinical outcome and seven-year survival of an independent series. A total of 610 Birmingham Hip Resurfacing arthroplasties were performed in 532 patients with a mean age of 51.8 years (16.5 to 81.6). They were followed for between two and eight years; 107 patients (120 hips) had been followed up for more than five years. Two patients were lost to follow-up. At a minimum of five years' follow-up, 79 of 85 hips (93%) had an excellent or good outcome according to the Harris hip score. The mean Oxford hip score was 16.1 points (sd 7.7) and the mean University of California Los Angeles activity score was 6.6 points (sd 1.9). There were no patients with definite radiological evidence of loosening or of narrowing of the femoral neck exceeding 10% of its width. There were 23 revisions (3.8%), giving an overall survival of 95% (95% confidence interval 85.3 to 99.2) at seven years. Fractured neck of femur in 12 hips was the most common indication for revision, followed by aseptic loosening in four. In three hips (three patients) (0.5%), failure was possibly related to metal debris. Considering that these patients are young and active these results are good, and support the use of resurfacing. Further study is needed to address the early failures, particularly those related to fracture and metal debris.     

Polyethylene Hip Resurfacing to Treat Arthritis and Severe Acetabular Insufficiency

Background

Hip dysplasia is the leading cause of hip arthritis in young adults. These patients often participate in active lifestyles that require a full and stable range of motion.