Marybeth Naughton

Alumina ceramic bearings for total hip arthroplasty: five-year results of a prospective randomized study.

Three hundred twenty-eight ceramic bearings were implanted by six surgeons in 316 patients as a part of a prospective randomized US Investigational Device Exemption study comparing alumina ceramic bearings with cobalt chrome-on-polyethylene bearings. There was no difference between the control metal-on-polyethylene and the alumina bearing couple patient cohorts regarding demographics or clinical scores through 7 years. Revision for any reason occurred in 2.7% of the patients with alumina bearings and 7.5% of the control patients with polyethylene bearings. Osteolysis was found in 1.4% of the patients with alumina bearings and in 14.0% of the control patients. At an average followup of 5.0 years (range, 1-86 months) no ceramic fractures or ceramic bearing failures have occurred. Results of this study suggest that alumina ceramics perform as well as the metal-on-polyethylene in clinical scores, but the patients with ceramic bearings had fewer revisions and less osteolysis. These results lead us to think that this new alumina ceramic bearing provides a safe option for younger and more active patients. Level of Evidence: Therapeutic study, Level I-1b (randomized controlled trial, no significant difference, but narrow confidence intervals). See the Guidelines for Authors for a complete description of levels of evidence.

Ceramic-on-ceramic total hip arthroplasty: update.

This prospective, randomized, multicenter study of alumina ceramic-on-alumina ceramic bearing couples includes 452 patients (475 hips). Their average age was 53 years with approximately two thirds men and 82% with osteoarthritis. At an average 8-year follow-up, clinical results were excellent and cortical erosions significantly less than in the conventional polyethylene-on-metal bearing group. Nine hips have undergone revision of one or both components for any reason. Of the 380 ceramic liners, 2 (0.5%) have fractured requiring reoperation, and 3 (0.8%) ceramic patients reported a transient squeaking sound, one of which had a head and liner change due to groin pain secondary to psoas tendinitis at 5 years. With no revisions for aseptic loosening and minimal cortical erosions, alumina-ceramic bearing couples are performing in a manner superior to the polyethylene-on-metal bearing in this young, active patient population.

Ceramic bearings for total hip arthroplasty have high survivorship at 10 years.

BackgroundCeramic bearings were introduced to reduce wear and increase long-term survivorship of total hip arthroplasty. In a previous study comparing ceramic with metal-on-polyethylene at 5 to 8 years, we found higher survivorship and no osteolysis for the ceramic bearings.Questions/PurposesWe asked whether ceramic bearings have equal or superior survivorship compared with that for metal-on-polyethylene at longer followup; we also determined survivorship of the implant systems, the presence or absence of radiographic osteolysis, and incidence of device squeaking.MethodsFive surgeons at five sites have followed 189 patients (216 hips) for a minimum of 10 years and average of 10.3 years (range, 10–12.4 years) comparing alumina ceramic bearings (144 hips) with cobalt chrome-on-polyethylene bearings (72 hips). We determined Kaplan-Meier survivorship of the bearing surface and implant systems and collected radiographic and clinical data.ResultsWe observed no difference between the control metal-on-polyethylene and the alumina-bearing couple cohorts with regard to bearing-related failures (98.9% versus 99.1%). Revisions for any reason occurred in 10.5% of the control patients and 3.1% of the patients with alumina bearings. All femoral implants remain well fixed (100%), whereas one acetabular component (1%) is unstable in the control group. Osteolysis occurred in 26% of the control patients and in none of the patients with alumina bearings. Squeaking occurred in two of 144 hips (1.4%) of the patients with ceramic bearings.ConclusionsPatients receiving the ceramic-on-ceramic bearings had fewer revisions for any reason and less osteolysis than the control metal-on-polyethylene at 10 years. Our data suggest ceramic bearings continue to provide an option for the young and more active patient and provide for a measure to compare other new alternative bearings that are currently available.Level of EvidenceLevel I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A titanium-encased alumina ceramic bearing for total hip arthroplasty: 3- to 5-year results.

We examined whether encasing the alumina ceramic total hip arthroplasty insert in a thin titanium sleeve would reduce significantly or eliminate insert chipping on impaction of the insert into the shell. We also compared results, including observations of osteolysis, of the Trident® study group with those of the predecessor alumina bearing couple design to determine clinical improvement and radiographic stability. Beginning in October 1996, 328 alumina ceramic bearings were implanted by six surgeons in 316 patients as a part of a prospective, randomized United States Investigational Device Exemption three-arm study comparing an alumina ceramic bearing with a control bearing of cobalt-chromium on polyethylene. In September 1999, a fourth arm of the study (Trident®) was added. The Trident® insert was recessed within a thin titanium sleeve. At three to five years followup, osteolysis was found in 0% of the patients with the Trident® insert and in 0.5% of the patients with an alumina bearing couple. At a mean followup of 4.2 years (range, 3-5 years) no ceramic chips, fractures, or ceramic bearing failures have occurred. Encasing the alumina ceramic insert in a titanium sleeve seems to have resolved the issue of insert chipping on impaction and supports the continued use of Trident® bearings in relatively young patients. Level of Evidence: Therapeutic study, Level II-1 (prospective comparative study-patients treated one way compared with a group of patients treated in another way at the same institution). See the Guidelines for Authors for a complete description of levels of evidence.

Results and lessons learned from a United States hip resurfacing investigational device exemption trial.

BACKGROUND Improvements in metal-on-metal bearings have made hybrid hip surface replacement a potential alternative for the young active patient with end-stage hip disease. Possible advantages include greater hip joint stability, bone preservation, and decreased osteolysis. In this study, we compared the clinical and radiographic results of a new resurfacing device with those in a historical group of standard total hip arthroplasties. METHODS In 2001, the Cormet 2000 Hip Resurfacing Investigational Device Exemption study was initiated at twelve centers. A total of 337 patients treated with unilateral hip surface replacement with the Cormet device were enrolled in that study. These patients were compared with 266 patients in a previous study who had undergone unilateral total hip arthroplasty with ceramic bearing surfaces. Clinical and radiographic results were compared at similar time intervals. A newly recommended performance standard, the composite clinical success score, was used to assess non-inferiority of the hip resurfacing compared with the total hip arthroplasty used in the historical comparison population. RESULTS At the time of follow-up, at a minimum of two years, the Harris hip scores were comparable between the resurfacing and total hip arthroplasty groups. Statistical evaluation of the composite clinical success scores confirmed the non-inferiority hypothesis. Revision was required in twenty-four patients in the resurfacing group and five patients in the total hip arthroplasty group. The most common cause of revision following resurfacing was failure of the femoral component (fracture of the femoral neck or loosening of the femoral component). CONCLUSIONS Careful review of this study population revealed several important criteria for successful introduction of this resurfacing device into the United States. These include careful patient selection based on clinical and radiographic parameters and attention to various surgical details of implantation. These findings can be used to focus the training process for surgeons who wish to add implantation of this device to their surgical armamentarium. Such efforts should help to ensure safe and effective introduction of this new technology.

Ceramic-on-Ceramic Hip Outcome at a 5- to 10-Year Interval: Has it Lived Up to Its Expectations?

This study reports revision and complication rates of a single cementless double-wedged tapered stem with an alumina-alumina bearing over 10 years since the beginning of premarket clinical trials. Of 930 hips (848 patients) implanted by 9 surgeons, there were 19 revisions at mean follow-up of 5.9 years compared to 10 revisions in the 123 hips implanted with the polyethylene control group at mean 7.8 years. The ongoing safety of alumina-alumina bearings is demonstrated through excellent (96.8%) survivorship at 10 years. Twenty-one patients reported 23 incidences of noise described as clicking, squeaking, popping, or creaking. Eight patients with 9 hips described the noise as squeaking, most occurring rarely and only 1 occurring frequently in a patient subsequently revised for a reason aside from the squeaking.

Use of an Alumina-on-Alumina Bearing System in Total Hip Arthroplasty for Osteonecrosis of the Hip

BACKGROUND The results of total hip arthroplasty in patients with osteonecrosis of the femoral head are not always optimal. The use of alumina-on-alumina interfaces in young and active patients may decrease wear and lower the rate of aseptic loosening of the implant and appears to be an attractive alternative to the use of conventional cobalt-chromium-on-polyethylene bearings. The purpose of this study was to evaluate the safety and efficacy of the alumina-on-alumina bearing in patients with osteonecrosis and to compare this group of patients to a group of similarly treated patients with osteoarthritis and a group of patients who received conventional cobalt-chromium-on-polyethylene bearings. METHODS Patients were selected from a United States Investigational Device Exemption multicenter prospective randomized clinical study that was initiated in 1996. Seventy patients with osteonecrosis of the femoral head (seventy-nine hips) received a cementless alumina-on-alumina bearing system and were directly matched to seventy-six patients with osteoarthritis of the hip (seventy-nine hips) who were managed with the same implant. Both groups were compared with twenty-five patients (twenty-six hips) with osteonecrosis and twenty-five patients (twenty-six hips) with osteoarthritis who were managed with a cementless cobalt-chromium-on-polyethylene bearing system. All patients received a cementless hydroxyapatite-coated femoral stem and were followed both clinically and radiographically. RESULTS The clinical outcomes for alumina-on-alumina bearings were similar for both osteonecrotic and osteoarthritic hips. The seven-year survival probability was 95.5% for the osteonecrotic hips and 89.4% for the osteoarthritic hips in the alumina-on-alumina bearing group and 92.3% for the osteonecrotic hips and 92.9% for the osteoarthritic hips in the cobalt-chromium-on-polyethylene bearing group. At the time of the most recent follow-up, the mean Harris hip score was 96 points for both the osteonecrotic and the osteoarthritic hips in the alumina-on-alumina group and 96 points for the osteonecrotic hips and 97 points for the osteoarthritic hips in the cobalt-chromium-on-polyethylene bearing group. CONCLUSIONS The results of the use of alumina-on-alumina and cobalt-chromium-on-polyethylene bearings in cementless standard total hip implants in patients with osteonecrosis and osteoarthritis were comparable. The low revision rate for the alumina-on-alumina bearing is encouraging and offers a promising option for younger, more active patients who have this challenging disease. LEVEL OF EVIDENCE Therapeutic Level III. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

The effect of preoperative planning and impaction grafting surgical technique on intraoperative and postoperative complication rate for femoral revision patients with moderate to severe bone loss mean 4.7-year results.

This study reports the results of 41 revision hips, implanted by a single surgeon using impaction grafting (mean follow-up, 4.7 years). All hips had Paprosky scores of III or IV. Harris hip scores improved from 43 to 82. There was 1 intraoperative and 2 postoperative fractures. A single stem was revised during the study. Radiographic review showed the 40 unrevised stems to be stable, and graft incorporation was seen in at least 1 zone in 100% of the femurs. There was no stem subsidence greater than 2.5 mm. The results of this study demonstrate that preoperative planning and a surgical technique, which emphasizes femoral support and vigorous impaction grafting, resulted in an acceptable incidence of complications.

Controversies Regarding Bearing Surfaces in Total Hip Replacement

• Understand the indications and known methods for the use of alternative bearing surfaces as compared with the use of conventional polyethylene • Describe the major disadvantages or potential risks of using the new alternative bearings as compared with conventional polyethylene.

Patient Factors Predict Functional Outcomes After Cruciate Retaining TKA A 2-Year Follow-Up Analysis

We analyzed preoperative patient characteristics and postoperative functional outcomes to identify the most predictive preoperative characteristics of postoperative functional outcome for Cruciate Retaining (CR) TKA. In a prospective, multicenter study, 307 knees with minimum 2-year follow-up were first divided into groups based on 2-year functional performance. Logistic regression then determined SF-36 General Health Score (GHS) to be the most predictive preoperative patient characteristic. Subsequently, a second analysis was performed using preoperative SF-36 GHS to stratify patients into groups. Statistical significance was achieved in both analyses by gender, BMI and hypertension. Statistical significance was achieved in a single analysis by age, preoperative narcotic use, preoperative metabolic medication usage, preoperative pulmonary disease and preoperative use of medication for anxiety or depression.