Ceramic-on-ceramic vs ceramic-on-polyethylene,a comparative study with 10-year follow-up

BACKGROUND In press-fit total hip arthroplasty(THA)ceramic-on-ceramic(CoC)bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene(CoPE)bearings,and can lead to wear-induced osteolysis,resulting in loosening of the implant.However,CoC bearings show disadvantages as well,such as squeaking sounds and being more fragile,which can cause ceramic head or liner fracture.Because comparative long-term studies are limited,the objective of this study was to determine the long-term difference in wear,identify potential predictive factors for wear,investigate radiological findings such as osteolysis,and evaluate clinical functioning and complications between these bearings.AIM To determine 10-year differences in wear,predictive factors for wear,and investigate radiological findings and clinical functioning between CoC and CoPE.METHODS This observational prospective single-center cohort study with a 10-year followup includes a documented series of elective THAs.Primary outcome was wear measured by anteroposterior(AP)radiographs.Secondary outcomes were potential predictive factors for wear,complications during follow-up,Harris hip score(HHS),and radiological findings such as presence of radiolucency,osteolysis,atrophy,and hypertrophy around the cup.Due to the absence of wear in the CoC group,stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis.HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis,adjusted for potential confounders.RESULTS A total of 17 CoPE(63.0%)and 25 CoC(73.5%)cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year(range 0.010;0.350)and 0.000 mm/year(range 0.000;0.005),which was significant(P<0.001)between both groups.Wear always occurred in the cranial direction.Cup inclination was the only predictive factor for polyethylene(PE)wear.No dislocations,ceramic head,or liner fractures were seen.The HHS showed a mean change from baseline of 37.1 points(SD 18.5)in the CoPE group and 43.9(SD 17.0)in the CoC group.This crude difference of 6.8(range-5.2;18.7)in favor of the CoC group was not significant(P=0.26)and was not significant when adjusted for age,gender,and diagnosis either(P=0.99).No significant differences in complications and radiological findings were seen between groups.CONCLUSION CoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications,HHS,and radiological findings.

Fourth-generation ceramic-on-ceramic total hip arthroplasty in patients of 55 years or younger： short-term results and complications analysis

Background The incidence of total hip replacement in the younger and more active patients is ever increasing.The ceramic-on-ceramic （COC） bearing was developed to reduce wear debris-induced osteolysis and loosening and to improve the longevity of hip arthroplasties.Few studies have reported the clinical results and complications of the new zirconia-toughened ceramic total hip arthroplasty （THA）.Methods A consecutive series of 132 young patients （177 hips） that underwent primary cementless THAs between January 2010 and December 2012 were included in this study.These arthroplasties all had fourth-generation COC bearings performed through a posterolateral approach.The average age was （41.8±8.3） years （ranging from 22 to 55 years）,and the mean follow-up period was （24.5±9.4） months （ranging from 12 to 47 months）.The results were evaluated both clinically and radiographically.Harris hip score （HHS） was determined before surgery and at the time of each follow-up.Presence of postoperative groin or thigh pain and squeaking were recorded.Other complications such as dislocations,periprosthetic fractures,and ceramic components fractures were diagnosed and treated in emergency.Results The average HHSs improved from preoperative 60.3±10.7 （ranging from 29 to 76） to 91.0±5.1 （ranging from 74 to 100） at the final follow-up （t=-45.064,P ＜0.05）,and 97.7％ of cases were scored as excellent and good results.At the last follow-up,incidental inguinal pain was found in three hips （1.7％） and thigh pain in 11 hips （6.2％）.Radiographs showed a high rate of new bone formation around the acetabular and stem components.No obvious osteolysis or prosthesis loosening was detected.Complications occurred in six hips （3.4％）：posterior dislocation in two hips （1.1％）,periprosthetic femoral fracture in one hip （0.6％）,asymptomatic squeaking in two hips （1.1％）,and ceramic liner fracture in one hip （0.6％）.Conclusions The fourth-generation COC THA showed excellent clinical results in younger active patients with no osteolysis-related prosthesis failure at a short-term follow-up study.Surgeons should still be aware of the potential risks of complications such as dislocation,periprosthetic fracture,squeaking,and ceramic components fracture.

Hip Squeaking after Ceramic-on-ceramic Total Hip Arthroplasty

Objective： The present study aimed to review the characteristics and influencing factors of squeaking after ceramic-on-ceramic （CoC） total hip arthroplasty （THA） and to analyze the possible mechanisms of the audible noise. Data Sources： The data analyzed in this review were based on articles from PubMed and Web of Science. Study Selection： The articles selected for review were original articles and reviews found based on the following search terms： “total hip arthroplasty”, “ceramic-on-ceramic”, “hip squeaking”, and “hip noise.” Results： The mechanism of the squeaking remains unknown. The possible explanations included stripe wear, edge loading, a third body, fracture of the ceramic liner, and resonance of the prosthesis components. Squeaking occurrence is influenced by patient, surgical, and implant factors. Conclusions： Most studies indicated that squeaking after CoC THA was the consequence of increasing wear or impingement, caused by prosthesis design, patient characteristics, or surgical factors. However, as conflicts exist among different articles, the major reasons for the squeaking rernain to be identified.

Restoring Natural Hip Movements with Large Head (Ceramic on Ceramic) Total Hip Replacement: Experience of Our 150 Patients over 6 Years

Background: Asian cultures require floor-seated positions demanding a high range of motion (ROM). Ceramic-On-Ceramic (COC) interface allowed the use of larger head with reduced wear debris generation and adverse tissue reactions. This study was conducted to analyze 6-year clinical-radiological outcome with large head fourth generation DeltaMotion&reg;ceramic-on-ceramic (COC) hip articulation, with special emphasis on postoperative ROM, ability to sit cross-legged, stability, hip noise and revision surgery. Material and Methods: 150 consecutive hips were operated for primary cementless Total Hip Replacement (THR) using DeltaMotion&reg;at a tertiary care center in Mumbai, India, between January 2010 and January 2015. Clinico-radiological outcome was assessed using the Harris Hip Score (HHS) and radiographs at 6 weeks, 6 months, and annually thereafter. Results: 108 (74.5%) patients were males and 37 (25.5%) were females with an average age of 50.87 years. Mean follow-up was 54 months (range: 37 - 86 months). The mean ROM was 120° in flexion, 10° in extension, 30° in adduction, 45° in abduction, 25° in internal rotation and 25° in external rotation. The mean HHS showed a statistically significant improvement of 64.5% (from 54.66 ± 6.42 pre-operatively to 89.95 ± 4.32 post operatively) (p-value: 0.001). 92% of patients were able to sit in squatting position and 92% were able to sit cross-legged on the floor at last follow-up. 0.7% joints (1 hip) had squeaking. Considering no revision surgery as the end point, 6-year prosthesis survivorship was 100%. Complications (superficial infection) occurred in three hips (2%). All patients reported to be satisfied with their outcome after surgery. Conclusion: We infer that DeltaMotion large head COC bearing allows scope for using larger head size in relatively smaller Indian hips due to factory fitted ceramic lining. At 6-year follow-up, high activity level was observed with excellent clinical-radiological outcomes and component longevity in relatively young Indian population.

Ceramic on Ceramic or Ceramic-on-polyethylene for Total Hip Arthroplasty： A Systemic Review and Meta-analysis of Prospective Randomized Studies

Background：Wear debris of polyethylene has become a restraining factor of the durability for total hip arthroplasty （THA）.Ceramic on ceramic （COC） has better wear resistance while the squeaking sound and prosthesis fracture are of concern.It is still a controversy that bearing couples are better for THA.Methods：We performed a systematic review of all English articles identified from PubMed （1966-）,Embase （1980-） and the Cochrane Library.Clinical outcomes,complications,revision rates,and radiographic outcomes of COC-THA and ceramic on polyethylene （COP）-THA were compared and evaluated.Results：Eight prospective randomized trials enrolling a total of 1508 patients and 1702 THA surgeries were identified.Our results demonstrated the prosthesis fracture and the squeaking sound is significantly higher in COC group and higher wear rate of the COP.Hip function,loosening rate,dislocation rate,revision rate,and the osteolysis rate were comparable between two groups.According to Grading of Recommendations Assessment,Development and Evaluation system assessment,the strength of evidence was high for prosthesis fracture,dislocation,osteolysis,and moderate for radiolucent line or loosening,hip noise,and revision.Conclusions：Up to now,there is insufficient evidence to identify any clinical advantage of COC compared with COP.Longer follow-up of larger randomized trial is needed to clarify the outcomes.

Pure alumina bearings with cementless stems versus sandwich bearings with cemented stems in total hip arthroplasty

Background Ceramic bearing surfaces have been introduced to prevent osteolysis after total hip arthroplasty （THA）,but little is known about the difference in clinical and radiological results between pure alumina and sandwich alumina bearings.The purpose of this study was to analyze the results obtained with third-generation alumina-on-alumina THA with two different designs both in liner and femoral stem fixation after a minimum follow-up of 4.2 years.Methods The results of 195 primary alumina-on-alumina THAs in 167 patients were evaluated.The procedures were performed between January 1998 and October 2006.Three patients died and 11 patients were lost to follow-up,leaving a total of 153 patients （181 hips） available for study.In the 88 group A patients,107 hips were implanted using pure alumina bearings with cementless femoral stems.These patients were followed for （6.84±1.49） years.In the 65 group B patients,74 hips were implanted using sandwich alumina ceramic bearings with cemented femoral stems.These patients had a follow-up period of （7.73±1.60） years.Patients in both groups were evaluated clinically and radiographically.Results One ceramic liner fracture occurred in group A and five took place in group B （P 〈0.05）,four of them revised for liner fracture.In each group,one acetabular shell migration happened without liner breakage and two hips developed deep infections,and all these six hips received revisions.Nine femoral components loosened in group B,with seven undergoing revisions.Kaplan-Meier survivorship at 5 years for revision of any component for any reason in group A was 96.26% compared to 90.54% in group B （P 〈0.05）.Better function was determined in group A （average Harris hip scores：92.13±2.85） than in group B （average Harris hip scores：86.03±4.21） and the difference was significant （P 〈0.05）.Squeaking was not recorded in either group.Conclusions The sandwich design of the acetabular bearings can not reduce the migration rate in ceramic bearings but increase the liner fracture rate compared to pure ceramic liners.The high loosening rate in fluted and taped designed cemented stems with sandwich liners warrant caution to their use.