The natural history of ceramic-on-ceramic prosthetic hip squeak and its impact on patients

Background

Ceramic-on-ceramic (CoC) total hip arthroplasty (THA) has been scrutinised for a high incidence of post-operative squeak. The psychological and social consequences, and subsequent request for revision surgery are not well documented.

Methods

Seventy consecutive primary CoC THA operated on by a single surgeon at a single institution were enroled and followed for an average 7.1 years. Information was obtained from routine post-operative review, medical records, mailed questionnaire and periodic phone interview.

Results

Of 70 THA, 69 were available for follow-up. Seventeen (24.6 %) reported at least one instance of squeak, occurring on average 34.2 months post-operatively. Five (7.5 %) recalled being warned preoperatively of squeak as a potential complication. Six reported infrequent squeak and 11 frequent squeak. Ten were concerned, reporting embarrassment, harassment and anxiety regarding the longevity of their THA. One patient was planning revision surgery.

Discussion

This study demonstrates the highest published prevalence of squeaking CoC THA and highlights the importance of warning patients of this potential complication.     

Comparison of the risk of revision in cementless total hip arthroplasty with ceramic-on-ceramic and metal-on-polyethylene bearings

Background and purpose — Ceramic-on-ceramic (CoC) bearings were introduced in total hip arthroplasty (THA) to reduce problems related to polyethylene wear. We compared the 9-year revision risk for cementless CoC THA and for cementless metal-on-polyethylene (MoP) THA.

Patients and methods — In this prospective, population-based study from the Danish Hip Arthroplasty Registry, we identified all the primary cementless THAs that had been performed from 2002 through 2009 (n = 25,656). Of these, 1,773 THAs with CoC bearings and 9,323 THAs with MoP bearings were included in the study. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk.

Results — 444 revisions were identified: 4.0% for CoC THA (71 of 1,773) and 4.0% for MoP THA (373 of 9,323). No statistically significant difference in the risk of revision for any reason was found for CoC and MoP bearings after 9 years of follow-up (adjusted RR = 1.3, 95% CI: 0.72–2.4). Revision rates due to component failure were 0.5% (n = 8) for CoC bearings and 0.1% (n = 6) for MoP bearings (p < 0.001). 6 patients with CoC bearings (0.34%) underwent revision due to ceramic fracture.

Interpretation — When compared to the “standard” MoP bearings, CoC THA had a 33% higher (though not statistically significantly higher) risk of revision for any reason at 9 years.     

High Incidence of Squeaking in THAs with Alumina Ceramic-on-ceramic Bearings

Ceramic-on-ceramic bearings in THA are a popular alternative to overcome wear concerns in traditional metal-polyethylene bearings. However, squeaking is a potentially worrisome phenomenon in ceramic-on-ceramic THAs which we observed in some of our patients. We reviewed all 42 patients who underwent 43 ceramic-on-ceramic noncemented THAs during the time of the study. Squeaking, defined as a reproducible sound of squeaking, clicking, or grating, occurred in nine of 43 implants (20.9%). Standard radiographs were normal. We used CT imaging to determine cup anteversion and inclination angles, comparing the squeaking hips with those of a randomly selected control group, but found no differences. We then hypothesized specific design features (stem size, cup size, head size, and neck length of the head) would be risk factors for squeaking. We found a difference in neck length between squeaking and nonsqueaking implants. A neck length of −4 mm or shorter resulted in a relative risk of 5.56 (95% confidence interval, 1.14–27.01) for squeaking. We found a high incidence of squeaking in our population, and we believe this phenomenon is an underreported side effect of these types of bearings. A short neck length of the femoral implant was a risk factor for squeaking in ceramic-on-ceramic THA. Level of Evidence: Level III, therapeutic study. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved or waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.     

Squeaking in ceramic‐on‐ceramic hips: No evidence of contribution from the trunnion morse taper

Squeaking in ceramic‐on‐ceramic (CoC) total hip arthroplasty (THA) was investigated with an acoustic monitoring device to distinguish between squeaking emanating from the trunnion morse taper (TMT) connection versus the articular surface. 82 patients with implant problems scheduled for revision were selected and acoustic emissions (AE) with simple movements monitored. Five of these patients with CoC implants underwent surgery and their retrieved implant components were analyzed in vitro. In vivo recordings of all 82 patients found audible squeaks produce frequency content across the entire 0–50 kHz spectrum. Of the five CoC implants the in vivo peak frequency range of flexion/extension motions was 0.8 kHz and comparable to the range of in vitro testing (0.2 kHz). In vitro TMT connection motions were very large comparatively, producing a higher average peak frequency range of 22.5 kHz. All retrieved implants showed evidence of wear at the TMT connection. These findings suggest, the TMT connection does not directly cause audible squeaking. Wear occurring at this junction may contribute to debris which disrupt lubrication, increase friction, and produce noise. This observation supports current evidence suggesting that squeaking is from the bearing surface. Our findings are the first to demonstrate that in CoC THA the recordable noise of a hip squeak does not originate nor have contribution from the TMT connection. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1793–1798, 2017.

     

Computer Navigation Helps Reduce the Incidence of Noise After Ceramic-on-Ceramic Total Hip Arthroplasty

Background

Noise after ceramic-on-ceramic (CoC) total hip arthroplasty (THA) is a well-recognized problem. Computer navigation has been shown to achieve desired implant orientation. Our aim was (1) to compare the incidence of noise between navigated and conventional CoC THAs and (2) to determine the factors associated with noise.

Hip squeaking: a 10-year follow-up study

The aim of the study was to analyze the incidence of squeaking with ceramic-on-ceramic total hip arthroplasty (THA) after 10 years of follow-up and the potential complications that could occur related to this phenomenon. One hundred THAs implanted between November 1999 and December 2000 were evaluated. Incidence of squeaking was investigated clinically with a questionnaire. Implant positioning was analyzed on x-rays and computer tomography. Of the 100 THAs, 5 patients presented with squeaking. All of them were active, sporty, and heavy men. Functional scores were comparable with nonsqueaking patients. There was no malpositioning on the x-ray analysis, no wear, and no loosening. We could not demonstrate any relation between squeaking and ceramic fracture. Squeaking noise appeared at a mean of 66 months postsurgery. It appears to be an isolated phenomenon without any consequences at 10-year follow-up.     

Fourth‐Generation Ceramic‐on‐Ceramic THA in Patients with Ankylosing Spondylitis: A Minimum 10‐Year Follow‐Up

ObjectiveTo report the long‐term outcomes of total hip arthroplasty (THA) with fourth‐generation ceramic‐on‐ceramic (CoC) bearing in patients with ankylosing spondylitis (AS).MethodsWe retrospectively identified 180 primary THAs performed in 110 patients with AS, including 100 (90.9%) men and 10 women (9.1%), from 2009 to 2011.The mean age of the patients at surgery was 33 years (range, 16 to 65 years). Cementless prostheses with fourth‐generation CoC bearings were used in all patients. Survivorship of the implants and postoperative complications were calculated. Functional improvement was assessed by the hip flexion‐extension range of motion (ROM) and Harris hip score (HHS). A special noise assessment questionnaire was performed at the last follow‐up. The cumulative incidence of noise was calculated by the Kaplan–Meier method with 95% confidence intervals (CIs). Clinical characteristics and functional outcomes were compared in the hips with noise to those without noise.ResultsThe mean follow‐up was 11 years (range, 10 to 12 years), and survivorship of the implants was 99.4% at the most recent follow‐up. The complications included dislocation (one hip, 0.6%), periprosthetic joint infection (one hip, 0.6%), mild to moderate pain (five hips, 2.8%), heterotopic ossification (12 hips, 6.7%), and noise (52 hips, 28.9%). The flexion‐extension ROM improved significantly with a median from 10° (range, 0 ~ 130°) to 100° (30 ~ 130°) after THA (p < 0.001), and the HHS increased significantly from 41 ± 20 to 90 ± 8 (p < 0.001). The cumulative incidence of noise at 0.5, 5, and 10 years was 6.1% (95% CI, 2.6 ~ 9.6), 16.7% (95% CI, 11.2 ~ 22.1), and 28.9% (95% CI, 22.2 ~ 35.5), respectively, and that of squeaking at 0.5, 5, and 10 years was 4.4% (95% CI, 1.4 ~ 7.4), 13.3% (95% CI, 8.4 ~ 18.3), and 23.9% (95% CI, 17.6 ~ 30.1), respectively. None of the patients with noise generation in the hip reported it affecting daily activities or causing dissatisfaction. No differences in age, sex, BMI, disease duration, bilateral THA, the frequency of bony ankylosis, the proportion of using a 36‐mm‐diameter femoral head, pre/postoperative flexion‐extension ROM, or pre/postoperative HHS were found between hips with noise and those without noise (p > 0.05).ConclusionTHAs with fourth‐generation CoC bearings exhibit excellent long‐term survival and clinical outcomes in patients with AS, with a very low dislocation rate. The incidence of noise associated with CoC bearings in THA performed in patients increases over time, but it does not affect postoperative hip function or daily activities.     

Do different types of bearings and noise from total hip arthroplasty influence hip-related pain,function, and quality of life postoperatively?

Background and purpose — Patient-reported outcome (PRO) is recognized as an important tool for evaluating the outcome and satisfaction after total hip arthroplasty (THA). We wanted to compare patient-reported outcome measure (PROM) scores from patients with ceramic-on-ceramic (CoC) THAs and those with metal-on-metal (MoM) THAs to scores from patients with metal-on-polyethylene (MoP) THAs, and to determine the influence of THA-related noise on PROM scores.

Patients and methods — We conducted a nationwide cross-sectional questionnaire survey in a cohort of patients identified from the Danish Hip Arthroplasty Registry. The PROMs included were: hip dysfunction and osteoarthritis and outcome score (HOOS), EQ-5D-3L, EQ VAS, UCLA activity score, and questions about noise from the THA. The response rate was 85% and the number of responders was 3,089. Of these, 45% had CoC THAs, 17% had MoM THAs, and 38% had MoP THAs, with a mean length of follow-up of 7, 5, and 7 years, respectively.

Results — Compared to MoP THAs, the mean PROM scores for CoC and MoM THAs were similar, except that CoC THAs had a lower mean score for HOOS Symptoms than did MoP THA. 27% of patients with CoC THAs, 29% with MoM THAs, and 12% with MoP THAs reported noise from their hip. For the 3 types of bearings, PROM scores from patients with a noisy THA were statistically significantly worse than those from patients with a silent MoP THA. The exception was noisy CoC and MoM THAs, which had the same mean UCLA activity score as silent MoP THAs.

Interpretation — A high proportion of patients reported noise from the THA, and these patients had worse PROM scores than patients with silent MoP THAs.     

Clinical Outcomes,Metal Ion Levels,Lymphocyte Profiles,and Implant Survival Following Five Different Bearings of Total Hip Arthroplasty: A Mean 10-year Follow-up Study

BackgroundDifferent bearings have been used in total hip arthroplasty (THA), but the long-term performance is still controversial. The purpose of this study was to investigate whether there are differences when comparing THAs with 5 different bearings at a long-term follow-up of more than 10 years.MethodsFrom January 2010 to May 2012, 101 THA patients (134 hips) were divided into metal-on-metal group (MoM, 31 hips), metal-on-polyethylene group (MoP, 23 hips), ceramic-on-metal group (CoM, 21 hips), ceramic-on-ceramic group (CoC, 33 hips), and ceramic-on-polyethylene group (CoP, 26 hips). The mean follow-up period was 10.3 years. The Harris hip score (HSS), Western Ontario and McMaster Universities Osteoarthritis Index scores (WOMAC), range of motion (ROM), blood cell count, and liver-kidney function were measured. Serum and urine metal ion levels were measured using high-resolution inductively coupled plasma-mass spectrometry (ICP-MS) and a blood lymphocytes analysis was counted by flow cytometry.ResultsNo difference was observed in the HSS, WOMAC, ROM, blood cell count, or liver-kidney function among any of the 5 groups. Metal ion levels were significantly elevated in metal-containing bearings. Flow cytometry showed that no differences were found. Revision was performed due to pseudotumor in 3 patients. The implant survival rate was 96.7% and 93.3% for the MoM and CoC groups, which was significantly lower compared with other groups.ConclusionsMetal ion levels were elevated significantly in metal-containing bearings, especially in MoM THA patients. The implant survival rate was significantly lower in CoC and MoM THAs, which was mainly due to pseudotumor formation.Level of EvidenceTherapeutic Level II.     

Third and fourth generation ceramic-on-ceramic total hip arthroplasty at a minimum of ten years

BackgroundCeramic on Ceramic bearings in Total Hip Arthroplasty (THA) afford a low friction coefficient, low wear rates and extreme hardness. Significant complications include hip squeak, ceramic fracture and poor polyethylene performance in revision procedures due to imbedding of abrasive microscopic ceramic fragments. We report on the results of this bearing at a minimum of 10 years.MethodsA single-centre retrospective review of 449 THAs was performed. Primary outcome measures included aseptic revision and all-cause revision rates at a minimum of 10 years post operatively. Evaluation of functionality was performed with WOMAC and SF-36 scores which were performed pre-operatively and at intervals of 6 months, one year, 2 years, 5 years and 10 years post operatively.ResultsThere was a 6.2% (n = 28) all-cause and 5.3% (n = 24) aseptic revision rate for ceramic on ceramic total hip arthroplasty at minimum of 10 years with a mean time to revision 4.8 years (range 2 months–11.6 years). Notably, there were 2 revisions for ceramic head fracture, one for ceramic liner fracture, 3 for aseptic loosening and 3 revisions for squeaking. Pain of unknown origin was the most common reason for revision. There was an improvement in postoperative WOMAC scores from a mean of 59.8 (range 15–95) pre-operatively to a mean of 15.6 (range 0–78) at 10 years.ConclusionThis study showed good functional outcomes but high revision rates for CoC THA at a minimum of 10 years. Our rates of ceramic fracture were consistent with other studies.     

Squeaking as a cause for revision of a composite ceramic cup

Squeaking in total hip arthroplasty (THA) has been observed only in hard-on-hard bearings, such as ceramic-on-ceramic or metal-on-metal. We report the case of a patient with a squeaking THA who had undergone multiple femoral head revisions combined with a composite ceramic cup (polyurethane, ceramic). Squeaking started 6 years postoperatively and acetabular revision was necessary to resolve the issue. Secondary deformation of the inlay resulted in clamping of the femoral head and increased friction. This should be considered when assessing and advising patients with squeaking THA when composite ceramic components are involved.     

The Acetabular Wall Index Is Associated with Long-term Conversion to THA after PAO

BackgroundPeriacetabular osteotomy (PAO) has been shown to be a valuable option for delaying the onset of osteoarthritis in patients with hip dysplasia. Published studies at 30 years of follow-up found that postoperative anterior overcoverage and posterior undercoverage were associated with early conversion to THA. The anterior and posterior wall indices are practical tools for assessing AP coverage on standard AP radiographs of the pelvis pre-, intra-, and postoperatively. However, no study that we know of has evaluated the relationship between the postoperative anterior and posterior wall indices and survivorship free from arthroplasty.Questions/purposesIn a study including patients after PAO for developmental dysplasia of the hip (DDH), we evaluated whether the acetabular wall index is associated with conversion to THA in the long-term after PAO. We asked: (1) Is an abnormal postoperative anterior wall index associated with conversion to THA after PAO? (2) Is an abnormal postoperative posterior wall index associated with conversion to THA after PAO? (3) Are there other factors associated with joint replacement after PAO?MethodsThis retrospective study involved pooling data of PAO for DDH from two previously published sources. The first series (1984-1987) comprised the very first 75 PAOs for symptomatic DDH performed at the inventor’s institution. The second (1997-2000) comprised a series of PAOs for symptomatic DDH completed at the same institution 10 years later. No patient was lost to follow-up. Fifty hips (44 patients) were excluded for predefined reasons (previous surgery, substantial femoral pathomorphologies, poor-quality radiographs), leaving 115 hips (102 patients, mean age 29 ± 11 years, 28% male) for analysis with a mean follow-up of 22 ± 6 years. One observer not involved in patient treatment digitally measured the anterior and posterior wall indices on postoperative AP pelvic radiographs of all patients. All patients were contacted by mail or telephone to confirm any conversion to THA and the timing of that procedure relative to the index procedure. We performed univariate and multivariate Cox regression analyses using conversion to THA as our endpoint to determine whether the anterior and posterior wall indices are associated with prosthetic replacement in the long-term after PAO. Thirty-one percent (36 of 115) of hips were converted to THA within a mean of 15 ± 7 years until failure. The mean follow-up duration of the remaining patients was 22 ± 6 years.ResultsA deficient anterior wall index was associated with conversion THA in the long-term after PAO (adjusted hazard ratio 10 [95% CI 3.6 to 27.9]; p < 0.001). Although observed in the univariate analysis, we could not find a multivariate association between the posterior wall index and a higher conversion rate to THA. Grade 0 Tönnis osteoarthritis was associated with joint preservation (adjusted HR 0.2 [95% CI 0.07 to 0.47]; p = 0.005). Tönnis osteoarthritis Grades 2 and 3 were associated with conversion to THA (adjusted HR 2.3 [95% CI 0.9 to 5.7]; p = 0.08).ConclusionA deficient anterior wall index is associated with a decreased survivorship of the native hip in the long-term after PAO. Intraoperatively, in addition to following established radiographical guidelines, the acetabular wall indices should be measured systematically to ascertain optimal acetabular fragment version to increase the likelihood of reconstructive survival after PAO for DDH.Level of EvidenceLevel III, therapeutic study.     

Cementless total hip arthroplasty with ceramic-on-ceramic bearing in patients younger than 45 years with femoral-head osteonecrosis

Despite improvements in the quality of alumina ceramics, osteolysis has been reported anecdotally after total hip arthroplasty (THA) with use of a contemporary alumina-on-alumina ceramic bearing. The purpose of this study was to evaluate the clinical and radiographic outcomes of THA using alumina-on-alumina ceramic bearing and to determine osteolysis using radiographs and computed tomographic (CT) scans in young patients. Consecutive primary cementless THA using alumina-on-alumina ceramic bearing were performed in 64 patients (93 hips) who were younger than 45 years of age with femoral-head osteonecrosis. There were 55 men (84 hips) and nine women (nine hips). Average age was 38.2 (range 24–45) years. Average follow-up was 11.1 (range 10–13) years. Preoperative Harris Hip Score was 52.9 (range 22–58) points, which improved to 96 (range 85−100) points at the final follow-up examination. Two of 93 hips (2%) had clicking or squeaking sound. No hip had revision or aseptic loosening. Radiographs and CT scans demonstrated that no acetabular or femoral osteolysis was detected in any hip at the latest follow-up. Contemporary cementless acetabular and femoral components with alumina-on-alumina ceramic bearing couples function well with no osteolysis at a ten year minimum and average of 11.1-year follow-up in this series of young patients with femoral-head osteonecrosis.     

Component positioning and ceramic damage in cementless ceramic-on-ceramic total hip arthroplasty

BackgroundIn ceramic-on-ceramic (CoC) total hip arthroplasty (THA), component positioning demonstrated to influence the bearing damage: however the connection between angles and clinical outcomes at long-term follow-ups is currently lacking. Aims of this study were: the computer tomography (CT) assessment of component positioning in CoC THAs; the correlation analysis between positioning and ceramic damage; the identification of safe zones.Methods91 consecutive post-operative CT scans including two types of CoC implants, with a mean follow-up of 12 ± 4.4 years, were evaluated. III generation (74.2%) and IV generation (25.8%) CoC surfaces were included. The angle measurements (cup abduction, anteversion, cup tilt, stem antetorsion, sacral slope) were automated using a CT-based software. The combined anteversion was assessed as well as the cup-neck position at −15°, 0°, 45° and 90° of flexion. Ceramic damage was diagnosed using synovial fluid analyses and radiological criteria.Results63.7% of THAs was inside the cup abduction target 30°–45° and 68.1% was inside the cup anteversion target 5°–25°. 19 patients (20.9%) showed signs of ceramic damage. High cup abduction and high cup-neck 45° minimum angle (which stood for high abduction and extreme combined version) significantly correlated with ceramic damage. No demographical features apart III generation ceramic bearings influenced the results. No safe zones could be detected.ConclusionsIn CoC THA, no safe zones can be described. However it is important to avoid cup inclination over 45° and a combination of steep cup and extreme combined version.     

Primary Total Hip Arthroplasty With Ceramic-On-Ceramic Articulations: Analysis of a Single-Center Series of 1,083 Hips at a Minimum of 10-Year Follow-Up

BackgroundThere are limited long-term results of using ceramic-on-ceramic (CoC) bearings in total hip arthroplasty (THA) in a large number of patient cohorts. The purpose of this study was to evaluate the minimum 10-year clinical and radiological outcomes and survivorship in a single surgeon series of CoC-THA.MethodsAmong the 1,039 patients (1,391 hips) who underwent primary THA at our institution between 2008 and 2011, 49 patients (69 hips) experienced paralysis or death, and 194 patients (239 hips, 19%) were lost to follow-up. The remaining 796 patients (1,083 hips) were assessed at a mean of 11 years (range, 10 to 13 years) using the modified Harris hip score (mHHS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and a questionnaire on articular noises. Survival analysis was used to estimate the survivorship. Radiological evaluation was performed on 869 hips at the final follow-up.ResultsSurvivorship at 11 years was 98.3% for revision or aseptic loosening, and 98.2% for reoperation. At the final follow-up, the mean mHHS and WOMAC scores were 93 (range, 12 to 100) and 14.4 (range, 3 to 66), respectively. There were 131 (12%) hips that experienced squeaking, but no patient required revision. No fracture of the ceramic was observed. Radiological evaluation at the final follow-up revealed that 3 (0.3%) hips exhibited loosening, 2 (0.2%) had femoral osteolysis, 81(9.3%) acquired radiolucencies, and 35 (4%) showed heterotopic ossification.ConclusionThis CoC bearing for THA had a high survivorship and excellent functional outcomes for at least 10 years.     

A Squeaky Reputation: The Problem May Be Design-dependent

Background  

Squeaking is reportedly a complication in patients having ceramic-on-ceramic total hip implants. The etiology remains unknown and multifactorial with recent studies suggesting a relationship between the audible squeak and implant design. When we evaluated our ceramic-on-ceramic cohort, we noticed squeaking primarily in patients receiving an acetabular system designed with an elevated titanium rim.     

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

BACKGROUNDIn 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.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up 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.RESULTSA 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. CONCLUSIONCoC 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.     

What Are the Frequency,Related Mortality,and Factors Associated with Bone Cement Implantation Syndrome in Arthroplasty Surgery?

BackgroundBone cement implantation syndrome (BCIS) is characterized by hypoxia, hypotension, and the loss of consciousness during cemented arthroplasty; it may result in death. Its incidence has only been explored for hemiarthroplasty and THA after fracture or cancer. To our knowledge, there are no studies that comprehensively explore and compare the incidence of BCIS in other arthroplasty procedures.Questions/purposes(1) To report the incidence of BCIS in TKA, unicondylar knee arthroplasty, hip hemiarthroplasty, THA, shoulder arthroplasty, TKA, and revision THA and TKA; (2) to determine whether severe BCIS is associated with an increased risk of death within 30 days of surgery; and (3) to identify factors associated with the development of severe BCIS.MethodsAll patients undergoing cemented arthroplasty for any reason (TKA [11% cemented, 766 of 7293], unicondylar knee arthroplasty [100% cemented, 562 procedures], hip hemiarthroplasty for femur fractures [100% cemented, 969 procedures], THA [8% cemented, 683 of 8447], shoulder arthroplasty [84% cemented, 185 of 219], and revision arthroplasty of the hip and knee [36% cemented, 240 of 660]) between January 2008 and August 2019 were considered for inclusion in the current retrospective observational study. Fixation choice was dependent on surgeon preference (THA and TKA), prosthesis design (shoulder arthroplasty), or bone quality (revision arthroplasty). The following procedures were excluded because of insufficient data: < 1% (1 of 766) of TKAs, 1% (4 of 562) of unicondylar knee arthroplasties, 6% (54 of 969) of hip hemiarthroplasties, 1% (6 of 683) of THAs, 6% (12 of 185) of shoulder arthroplasties, and 14% (34 of 240) of revision procedures. This resulted in a final inclusion of 3294 procedures (765 TKAs [23%], 558 unicondylar knee arthroplasties [17%], 915 hip hemiarthroplasties [28%], 677 THA [21%], 173 shoulder arthroplasties [5%], and 206 revision arthroplasties [6%]), of which 28% (930 of 3294) had an emergent indication for surgery. Of the patients, 68% (2240 of 3294) were females, with a mean age of 75 ± 11 years. All anesthetic records were extracted from our hospital’s database, and the severity of BCIS was retrospectively scored (Grade 0 [no BCIS], Grade 1 [O₂% < 94% or fall in systolic blood pressure of 20% to 40%], Grade 2 [O₂% < 88% or fall in systolic blood pressure of > 40%], and Grade 3 [cardiovascular collapse requiring CPR]). Procedures were dichotomized into no or moderate BCIS (Grades 0 and 1) and severe BCIS (Grades 2 and 3). The adjusted 30-day mortality of patients with severe BCIS was assessed with a multivariate Cox regression analysis. A multivariate logistic regression analysis was performed to identify factors associated with the development of severe BCIS.ResultsBCIS occurred in 26% (845 of 3294) of arthoplasty procedures. The incidence was 31% (282 of 915) in hip hemiarthroplasty, 28% (210 of 765) in TKA, 24% (165 of 677) in THA, 23% (47 of 206) in revision arthroplasty, 20% (113 of 558) in unicondylar knee arthroplasty, and 16% (28 of 173) in shoulder arthroplasty. Patients with severe BCIS were more likely (hazard ratio 3.46 [95% confidence interval 2.07 to 5.77]; p < 0.001) to die within 30 days of the index procedure than were patients with less severe or no BCIS. Factors independently associated with the development of severe BCIS were age older than 75 years (odds ratio 1.57 [95% CI 1.09 to 2.27]; p = 0.02), American Society of Anesthesiologists Class III or IV (OR 1.58 [95% CI 1.09 to 2.30]; p = 0.02), and renal impairment (OR 3.32 [95% CI 1.45 to 7.46]; p = 0.004).ConclusionBCIS is common during cemented arthroplasty; severe BCIS is uncommon, but it is associated with an increased risk of death within 30 days of surgery. Medically complex patients undergoing hip hemiarthroplasty may be at particular risk. Patients at high risk for severe BCIS (renal impairment, ASA III/IV, and age older than 75 years) should be identified and preventive measures such as medullary lavage before cementation, femoral venting, and avoidance of excessive pressurization of implants should be taken to reduce the likelihood and consequences of BCIS. Because of the increased risk of periprosthetic fractures in uncemented hip stems, factors associated with the development of BCIS should be weighed against the risk factors for sustaining periprosthetic fractures (poor bone quality, female sex) to balance the risks of fixation method against those of BCIS for each patient.Level of EvidenceLevel III, therapeutic study.