Biomedical subjects

Marybeth Naughton

Publications and source records attributed to Marybeth Naughton.

4 recordsLinked to original sources

PubMed2006

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.

Adult↗

PubMed2005

Five-year experience with Crossfire highly cross-linked polyethylene.

UNLABELLED: Our purpose was to compare the clinical wear performance of highly cross-linked (Crossfire) polyethylene with conventional (N2Vac) polyethylene total hip bearings. We implanted 56 hips (47 patients) with Crossfire acetabular bearing liners and compared their wear performance with 53 conventional polyethylene inserts. Wear and clinical data were collected retrospectively at a minimum 4-year and average 5-year followup. The linear femoral head penetration rate measured from plain radiographs was 0.055 mm/year +/- 0.022 mm/year for the Crossfire polyethylene and 0.138 mm/year +/- 0.073 mm/year for the control, a reduction of 60% for the Crossfire components. Calculated annual wear was 0.036 mm/year for the Crossfire components and 0.131 mm/year for the controls, a reduction of 72%. Radiographic review at most recent followup showed a reduction in erosive osteolytic lesions of the proximal femur for the Crossfire components compared with controls, also suggesting a reduction in debris release for the Crossfire components. Complications leading to revision were not seen in the Crossfire or control groups. These clinical findings suggest that this particular highly cross-linked polyethylene can provide wear reduction and an alternate bearing surface for active patient populations. LEVEL OF EVIDENCE: Therapeutic study, Level III (retrospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

Aged↗

PubMed2005

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

UNLABELLED: 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.

Aluminum Oxide↗

PubMed2005

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

UNLABELLED: 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.

Aluminum Oxide↗