Rim Cracking of the Cross-Linked Longevity Polyethylene Acetabular Liner After Total Hip Arthroplasty

Highly cross-linked polyethylene (HCLPE) has been used extensively to decrease osteolysis and related implant failure in THA. We compared the wear rate of HCLPE and noncross-linked conventional PE (CPE) liners and the rate of radiographic calcar resorption and osteolysis in young patients (35-60 years of age) who underwent THA by one surgeon. Thirty-four patients (41 THAs) who received a hybrid THA using a HCLPE liner were matchpaired for age, gender, body mass index, and diagnosis with a group of patients who underwent THA with identical implants but with a CPE liner. The minimum followup was 4 years (average, 5.3; range, 4-8 years). Using the Livermore measurement technique, the averages of total wear of the HCLPE and CPE liners were 0.01 mm (range, -0.23-0.4) and 0.64 mm (range, 0-1.7), respectively. The average annual wear was less for the HCLPE than the noncross-linked PE (0.002 mm, range, -0.05-0.1 versus 0.12 mm, range, 0-0.29, respectively). Four hips in the HCLPE group and 23 in the CPE group had calcar resorption measuring averages of 2.5 mm (range, 2-3) and 7.5 mm (range, 1.8-23.8), respectively. Periprosthetic osteolysis occurred in two and eight hips in the HCLPE and CPE groups, respectively. Longer followup is needed to determine if these findings will result in improved implant survivorship.

Section: Discussionmentioning

confidence: 99%

Wear is Reduced in THA Performed with Highly Cross-linked Polyethylene

Beksaç

Salas²,

Valle

et al. 2009

“…The mechanical properties and oxidation of the bearing surface in retrieved annealed bearings have not yet shown evidence of degradation with implantation [78], suggesting the femoral head reduces in vivo oxidation at this location. For remelted polyethylenes, rim fracture has been reported in several case studies requiring revision of the bearing [42,57,58,101,131]. Common threads among rim fracture case studies include thin remelted liners, sometimes with an elevated rim, and vertical orientation (malpositioning) of the shell.…”

Section: Discussionmentioning

confidence: 99%

History and Systematic Review of Wear and Osteolysis Outcomes for First-generation Highly Crosslinked Polyethylene

Kurtz

Gawel

Patel

2011

403

282

Background Highly crosslinked polyethylene (HXLPE) was introduced to reduce wear and osteolysis in total joint arthroplasty. While many studies report wear and osteolysis associated with HXLPE, analytical techniques, clinical study design and followup, HXLPE formulation and implant design characteristics, and patient populations differ substantially among investigations, complicating a unified perspective. Questions/purposes Literature on first-generation HXLPE was summarized. We systematically reviewed the radiographic wear data and incidence of osteolysis for HXLPE in hip and knee arthroplasty. Methods PubMed identified 391 studies; 28 met inclusion criteria for a weighted-averages analysis of two-dimensional femoral head penetration rates. To determine the incidence of osteolysis, we estimated a pooled odds ratio using a random-effects model.Results Weighted-averages analyses of femoral head penetration rates in HXLPE liners and conventional UHMWPE liners resulted, respectively, in a mean twodimensional linear penetration rate of 0.042 mm/year based on 28 studies (n = 1503 hips) and 0.137 mm/year based on 18 studies (n = 695 hips). The pooled odds ratio for the risk of osteolysis in HXLPE versus conventional liners was 0.13 (95% confidence interval, 0.06-0.27) among studies with minimum 5-year followup. We identified two clinical studies of HXLPE in TKA, preventing systematic analysis of outcomes. Conclusions HXLPE liner studies consistently report lower femoral head penetration and an 87% lower risk of osteolysis. Reduction in femoral head penetration or osteolysis risk is not established for large-diameter ([ 32 mm) metallic femoral heads or ceramic femoral heads of any size. Few studies document the clinical performance of HXLPE in knees.

“…Although contemporary THAs with highly crosslinked polyethylene (HXLPE) or hard-on-hard bearings offer great hope for reducing wear, the reduction in wear observed in THAs with HXLPE appears to be not quite as dramatic as seen in those with hard-on-hard bearings [19,32], and those with metal-on-metal bearings have problematic issues such as hypersensitivity and pseudotumors [34].…”

Section: Introductionmentioning

confidence: 99%

Do Alumina Matrix Composite Bearings Decrease Hip Noises and Bearing Fractures at a Minimum of 5 Years After THA?

Baek

Kim

et al. 2015

Background Ceramic-on-ceramic bearing couples are theoretically attractive in total hip arthroplasty (THA) because of low wear, but concerns regarding ceramic fracture and squeaking have arisen. Improved material properties of newer alumina matrix composite (AMC) materials, known as Delta ceramics, may reduce these risks. In addition, the use of thinner liners and larger femoral heads may be helpful clinically to lower the rate of dislocation. However, limited short-term clinical results are available and intermediate-term effects are unclear. Questions/purposes (1) What is the frequency of bearingrelated complications (dissociation, fracture, and noise) with ceramic-on-ceramic AMC bearings in cementless THA? (2) What other complications arose in patients treated with these bearings? (3) What are the Harris hip scores (HHS) and survivorship free from reoperation and revision at a minimum of 5 years after cementless THA performed with AMC bearings? Methods Over a 9-month period in 2009, one surgeon performed 125 THAs, of which 100 (80% of the total) were performed with cementless, AMC bearings. During the period in question, the exclusion criteria for this implant were primary THAs with severe acetabular or femoral bone defect and revision THAs. Of these, 94 hips (95%) in 91 patients were available for analysis at a minimum of 5 years (range, 5-6 years), because five patients (six hips) had died. Mean age at the time of arthroplasty was 55 ± 14 years. Prostheses with an identical design and Biolox 1 Delta ceramics were used in all patients. Noise was classified into squeaking, clicking, grinding, and popping. Ceramic fracture, dislocation, and any other complications associated with the use of AMC ceramics were also investigated. Clinical evaluation included the modified HHS preoperatively and at each followup. Survivorship free from reoperation and revision was calculated using the Kaplan-Meier method. Results Of 91 patients, four developed bearing-related complications, including one with liner dissociation despite initial square seating and three with clicking. No patients had ceramic fractures. A single event of perioperative dislocation occurred in one patient and postoperative periprosthetic fracture occurred in two hips. Mean HHS improved from 56 to 93 points at the final followup (p \ 0.001). Survivorship at 5 years free from reoperation and revision was 96.8% and 97.9%, respectively.