Cup Abduction Angle Research Articles

Bone morphogenic protein-2 use in revision total hip arthroplasty with acetabular defects.

The restoration of acetabular bone stock during revision hip arthroplasty remains a challenge. There have been no clinical series reporting the efficacy of bone morphogenic protein-2 (rhBMP-2) in the revision hip setting. We retrospectively reviewed the radiographs and records of 15 patients who received rhBMP-2 mixed with allograft bone chips (+BMP), and 14 who received allograft bone chips alone (-BMP) for their acetabular defect during revision total hip arthroplasty with a mean two-year follow up. Radiographs were evaluated for acetabular defect size, superior cup migration, and changes in the lateral cup abduction angle. Modified Harris hip scores were used for evaluation of clinical outcomes. Patients in the +BMP group compared to the -BMP group had significantly larger amounts of cancellous bone chips used (72.1±35.5cc vs. 38.6±14.1cc; p=0.003). Mean rhBMP-2 used per case was 7.4±3.1mg in the +BMP group. Three patients in the -BMP group had cup migration which was not observed in the +BMP group. Mean Harris hip scores (HHS) improved post-operatively in both groups (40.1±20.9 to 71.9±19, p<.0001). No local adverse reaction was noted in the +BMP group. rhBMP-2 had modest clinical benefit in the setting of revision THA. Cost of this synthetic biologic versus the added clinical benefit should be carefully considered when being used in the revision hip setting.

Intraoperative fluoroscopy with a direct anterior approach reduces variation in acetabular cup abduction angle.

The purpose of this study was to compare acetabular cup position for 2 cohorts of total hip arthroplasty (THA) patients who had a direct anterior approach. 100 THA cases were performed with an anterior approach using intraoperative fluoroscopy (IF) to aid in cup positioning. Another group of 100 cases underwent THA with an anterior approach without the use of any fluoroscopy. Postoperative abduction and anteversion angles were measured using Martell's hip analysis software. Mean abduction angle was 43.2° (standard deviation (SD) = 4.5°) for the IF group versus 37.5°(SD = 7.4°) for cases without IF (p<0.001). 18% more cases with IF fell within the Lewinnek safe zone (p<0.001); however, a similar number of cases had over 50° of abduction. The mean anteversion angles of the two groups were also significantly different (IF 21.8° vs. 24.9°) (p<0.01). There was significantly less variation in cup position among the cases using IF with regards to abduction.

Retrieval and radiographic analysis of the Contour antiprotrusio cage.

Acetabular reconstruction in the setting of severe bone loss or pelvic discontinuity remains a challenging problem. Multiple methods of treatment have been described including antiprotrusio cages (APCs). The objective of this study is to combine biomechanical analysis of retrieved APCs with radiographic and clinical data to determine which factors influence or predict APC failure. 41 APCs were identified. Sequential radiographs were examined for cage and polyethylene cup abduction angles, change in centre of rotation, screw placement, progression of cage failure, and failure mechanism. Cages were manually examined for gross macroscopic findings, breakage, and the location of breakage. High-resolution microscopy was used for further analysis. 24 cages were included in the analysis. Mean age of patients was 64.5 years (range 43-85 years); average length of implantation was 42.5 months (range 3-108 months). Average cage abduction angles were 56°; abduction for the cemented polyethylene cup was 44°. 14 of 24 cages were broken; 10 were intact. Of the broken cages, 10/14 broke through a screw hole in the ischial flange or just superior to the ischial flange. In the intact group, 6/10 failed due to pullout of the ischial screws. All cages had superior and lateralised centres of rotation. The majority of cages failed due to breakage or pullout at the ischial flange. Pelvic discontinuity was a large risk factor for a broken cage. Future design and technique modifications may result in superior outcomes in these complex acetabular reconstructions.

Spinal Realignment for Adult Deformity: Three-column Osteotomies Alter Total Hip Acetabular Component Positioning.

A goal of adult spinal deformity surgery is correction of sagittal imbalance by increasing lumbar lordosis (LL), allowing a previously retroverted pelvis to normalize as evidenced by decreases in pelvic tilt (PT). Realignment of pelvic orientation may alter the position of preexisting total hip arthroplasties (THAs). Twenty-seven patients with unilateral THA who underwent thoracolumbar fusions for adult spinal deformity from the pelvis to L1 or above were retrospectively reviewed (levels fused, 10.3 [range, 6 to 17]; age, 70 ± 9 years). Comparisons of preoperative and postoperative spinal deformity parameters, acetabular tilt (AT), and acetabular cup abduction angle (CAA) were performed, with subgroup analysis for those who had undergone three-column osteotomy and those who had not. Preoperative deformity was severe, with findings of a sagittal vertical axis >9 cm, PT >25°, and pelvic incidence-LL >20°. Postoperatively, AT decreased significantly (-7° ± 10°; P < 0.001), signifying relative acetabular retroversion. Comparing patients with three-column osteotomy versus those without, AT changes were greater in those with three-column osteotomy (11° ± 7° and -2 ± 10°, respectively; P = 0.024). AT was significantly correlated with changes of PT (r = 0.704; P < 0.001) and LL (r = -0.481; P = 0.011). AT decreased (ie, retroverted) 1° for every 3.23° of LL or 1.13° of PT correction. The coronal plane CAA did not change substantially. Spinal deformity correction, with techniques such as three-column osteotomy, result in significant THA acetabular component repositioning in the sagittal plane. Resultant decreased AT (ie, retroversion) theoretically may affect tribology, wear, and joint stability and warrants further investigation.

Combined effect of cup abduction and anteversion angles on long-term wear evolution of PCD-on-PCD hip bearing couple

This paper presents a three-dimensional (3D) finite element (FE) modelling for the estimation of wear evolution on the acetabulum cup against the femoral head for the combinations of different abduction angle (35°, 45° and 55°) and anteversion angle (0°, 10°, 20°, 30° and 40°) for PCD-on-PCD hip bearing components. By implementing the actual physiological hip gait loading conditions and the rotational movement of a normal walking cycle in the FE model, the contact pressure and the sliding distance were calculated to predict the wear. The cup surface was updated in a suitable interval of gait cycles for the estimation of wear. Wear was simulated for 20 years implant's life in a human body. Simulation results showed that higher abduction angle and lower anteversion angle result in the least linear and volumetric wear as compared to other conditions considered.

Combined effect of cup abduction and anteversion angles on long-term wear evolution of PCD-on-PCD hip bearing couple

This paper presents a three-dimensional (3D) finite element (FE) modelling for the estimation of wear evolution on the acetabulum cup against the femoral head for the combinations of different abduction angle (35°, 45° and 55°) and anteversion angle (0°, 10°, 20°, 30° and 40°) for PCD-on-PCD hip bearing components. By implementing the actual physiological hip gait loading conditions and the rotational movement of a normal walking cycle in the FE model, the contact pressure and the sliding distance were calculated to predict the wear. The cup surface was updated in a suitable interval of gait cycles for the estimation of wear. Wear was simulated for 20 years implant's life in a human body. Simulation results showed that higher abduction angle and lower anteversion angle result in the least linear and volumetric wear as compared to other conditions considered.

Patient-specific hip geometry has greater effect on THA wear than femoral head size

In vivo linear penetration in total hip arthroplasty (THA) exhibits similar values for 28mm and 32mm femoral head diameter with considerable variations between and within the studies. It indicates factors other than femoral head diameter influence polyethylene wear. This study is intended to test the effect of patient׳s individual geometry of musculoskeletal system, acetabular cup orientation, and radius of femoral head on wear. Variation in patient׳s musculoskeletal geometry and acetabular cup placement is evaluated in two groups of patients implanted with 28mm and 32mm THA heads. Linear wear rate estimated by mathematical model is 0.165–0.185mm/year and 0.157–0.205mm/year for 28 and 32mm THA heads, respectively. Simulations show little influence femoral head size has on the estimated annual wear rate. Predicted annual linear wear depends mostly on the abduction angle of the acetabular cup and individual geometry of the musculoskeletal system of the hip, with the latter having the greatest affect on variation in linear wear rate.

The study of wear behaviors on abducted hip joint prostheses by an alternate finite element approach

An acetabular cup with larger abduction angles is able to affect the normal function of the cup seriously that may cause early failure of the total hip replacement (THR). Complexity of the finite element (FE) simulation in the wear analysis of the THR is usually concerned with the contact status, the computational effort, and the possible divergence of results, which become more difficult on THRs with larger cup abduction angles. In the study, we propose a FE approach with contact transformation that offers less computational effort. Related procedures, such as Lagrangian Multiplier, partitioned matrix inversion, detection of contact forces, continuity of contact surface, nodal area estimation, etc. are explained in this report. Through the transformed methodology, the computer round-off error is tremendously reduced and the embedded repetitive procedure can be processed precisely and quickly. Here, wear behaviors of THR with various abduction angles are investigated. The most commonly used combination, i.e., metal-on-polyethylene, is adopted in the current study where a cobalt-chromium femoral head is paired with an Ultra High Molecular Weight Polyethylene (UHMWPE) cup. In all illustrations, wear coefficients are estimated by self-averaging strategy with available experimental datum reported elsewhere. The results reveal that the THR with larger abduction angles may produce deeper depth of wear but the volume of wear presents an opposite tendency; these results are comparable with clinical and experimental reports. The current approach can be widely applied easily to fields such as the study of the wear behaviors on ante-version, impingement, and time-dependent behaviors of prostheses etc.

Predicting long-term wear performance of hard-on-hard bearing couples: effect of cup orientation.

Wear is the major cause of implant failure, resulting in expensive revision surgeries of total hip arthroplasty. Therefore, understanding of wear mechanism and its progression is crucial to improve the physiological performance of implants. This paper presents a three-dimensional (3D) finite element (FE) wear modeling approach to estimate evolution of wear in hard-on-hard bearing components with the effect of cup abduction angle. Three bearing couples were considered, and they were PCD-on-PCD, Al2O3-on-Al2O3 and Si3N4-on-Si3N4, while the cup abduction angle varied from 35° to 70° with an increment of 5°. By adopting actual physiological hip gait loading and rotational movement for normal walking cycle in FE modeling, the contact pressure and the sliding distance were calculated to predict wear. A femoral head of 32mm in diameter was considered, while a constant frictional contact at the inference between head and cup was used. During simulation, the geometry of cup surface was updated at a reasonable interval of gait cycles to consider the effect of wear. Wear was simulated for up to 20 million cycles which is an equivalent of 20years of implant's life in human body. Simulation results showed that compared to other two bearing couples, the predicted linear and volumetric wear in PCD-on-PCD couple exhibited the least wear evolution for all cup angles considered. The increase in abduction angle from 35° to 70° decreases the volumetric wear by 28% for all three bearing couples, due to the reduction in sliding distance. Steep cup angle, e.g., 70° for Al2O3 and Si3N4 bearing couples, encountered edge contact, which leads to more wear. Further, wear results were discussed and analyzed with respect to in vitro and/or clinical studies available in the literature to justify the efficacy of wear modeling.

Intraoperative Fluoroscopy Improves Component Position During Anterior Hip Arthroplasty.

The goal of this retrospective review was to determine whether fluoroscopic guidance improves acetabular cup abduction and anteversion alignment during anterior total hip arthroplasty. The authors retrospectively reviewed 199 patients (fluoroscopy group, 98; nonfluoroscopy group, 101) who underwent anterior total hip arthroplasty at a single center with and without C-arm fluoroscopy guidance. Included in the study were patients of any age who underwent primary anterior approach total hip arthroplasty performed by a single surgeon, with 6-month postoperative anteroposterior pelvis radiographs. Acetabular cup abduction and anteversion angles were measured and compared between groups. Mean acetabular cup abduction and anteversion angles were 43.4° (range, 26.0°-57.4°) and 23.1° (range, 17°-28°), respectively, in the fluoroscopy group. Mean abduction and anteversion angles were 45.9° (range, 29.7°-61.3°) and 23.1° (range, 17°-28°), respectively, after anterior total hip arthroplasty without the use of C-arm guidance (nonfluoroscopy group). The use of fluoroscopy was associated with a statistically significant difference in cup abduction (P=.002) but no statistically significant difference in anteversion angles. In the fluoroscopy group, 80% of implants were within the combined safe zone compared with 63% in the nonfluoroscopy group. A significantly higher percentage of both acetabular cup abduction angles and combined anteversion and abduction angles were in the safe zone in the fluoroscopy group. Fluoroscopy is not required for proper anteversion placement of acetabular components, but it may increase ideal safe zone placement of components.

Importance of maintaining the basic stress pathway above the acetabular dome during acetabular reconstruction

The basic stress pathway above the acetabular dome is important for the maintenance of implant stability in press-fit acetabular reconstruction of total hip arthroplasty. However, information on the basic stress pathway and its impact factors remains unclear. The objective of this study was to investigate the effects of the orientations and positions of the acetabular component on the basic stress pathway. The basic stress pathway above the acetabular dome was defined as two parts: 3D basic trabecular bone stress distribution and quantified basic cortical bone stress level, using two subject-specific finite element normal hip models. The effects were then analysed by generating 32 reconstructed acetabular cases with different cup abduction and anteversion angles within a range of 35–50° and 10–25°, respectively, and 12 cases with different hip centre heights within a range of 0–15 mm above the acetabular dome. The 3D trabecular stress distribution decreased remarkably in all cases, while the 80% of the basic cortical bone stress level was maintained in cases when the acetabular component was positioned at 10° or 15° anteversion and 40° or 45° abduction angles. The basic stress pathway above the acetabular dome was disturbed when the superior displacement of the hip centre exceeded 5 mm above the anatomical hip centre. Positioning the acetabular component correctly contributes to maintain the stress balance between the acetabular cup and the bone during acetabular reconstruction, thus helping restore the normal hip biomechanics and preserve the stability of the implants.

Clinical Results and Metal Ion Levels After Ceramic-on-Metal Total Hip Arthroplasty: A Mean 50-Month Prospective Single-Center Study

BackgroundThe aim of our study was to investigate the clinical results and serum metal ion levels in a cohort of patients who received total hip arthroplasty (THA) with ceramic-on-metal (CoM) bearings. MethodsFrom September 2009 to December 2011, 78 patients (89 hips) who underwent THA with CoM bearings were involved in this study. Harris Hip Score, Short-Form 12, and Western Ontario and McMaster Universities Osteoarthritis Index scores were measured and radiographs were taken for radiographic analysis. Serum metal ion levels of cobalt (Co), chromium (Cr), molybdenum (Mo), and titanium (Ti) were measured using high-resolution inductively coupled plasma-mass spectrometry. ResultsSevery-four patients (85 hips) were followed up at a mean of 50 months. At the end of follow-up, HSS, Short-Form 12, and Western Ontario and McMaster Universities Osteoarthritis Index scores were improved significantly compared with preoperative values. No intraoperative and postoperative complications occurred, and no radiolucency, osteolysis, and loosening was found from radiographic examination. Metal ion analysis showed that serum metal ions levels were significantly elevated compared with normal values. Spearman correlation analysis revealed that there was a correlation between 3 metal ion levels and body mass index(Co: r = 0.49, P < .01; Cr: r = 0.47, P < .01; Mo: r = 0.36, P = .04). No correlation was found between metal ion levels and age, cup abduction angle, cup anteversion angle, acetabular version, bilateral arthroplasty, cup screw used, hip stem implant type, or femoral head size. ConclusionOur study concluded that the use of a CoM THA is effective clinically, but the systemic metal ion levels are significantly elevated at midterm follow-up. Whether the elevated metal ion levels will induce an adverse reaction is unknown and long-term follow-up is need.

How does pelvic rotation or tilt affect radiographic measurement of acetabular component inclination angle during THA?

BackgroundIt is unclear how radiographic measurements of cup position are sensitive to deviations from a perfect AP pelvis image. PurposeTo quantify changes in radiographic measurements of cup abduction angle due to pelvic tilt or obliquity. MethodsPart A, a retrospective comparison of radiographic cup abduction angle measurements from intraoperative and post-operative radiographs of 23 patients undergoing THA. Part B, a pelvic sawbones model was used to quantify changes in radiographic measurement of cup abduction angle due to known changes in pelvic tilt or obliquity. ResultsPart A, a perfect AP pelvis was obtained in just 30% of intraoperative radiographs. The mean intraoperative cup angle measurement was underestimated by 3.4° compared to post-operative standard radiographs. In Part B, pelvic tilt caused cup abduction angle measurement to decrease on inlet view and increase on outlet view. Pelvic obliquity caused cup abduction angle measurement to decrease on obturator oblique view and increase on iliac oblique view. ConclusionsA trend exists toward slight underestimation of cup abduction angle measurement using intraoperative radiographs. Pelvic tilt or obliquity alters the measured cup abduction angle in known directions.

Comparison of Cup Alignment, Jump Distance, and Complications in Consecutive Series of Anterior Approach and Posterior Approach Total Hip Arthroplasty

The purpose of this study was to compare cup position, jump distance, and rate of dislocations in 100 total hip arthroplasty (THA) cases performed with the direct anterior approach (DAA) and 100 cases performed with the posterior approach (PA). Abduction and anteversion angles were measured using Martell Hip Analysis software. The average cup anteversion in the DAA group (17.6°) was significantly different than the PA average (22.6°), P<.001. The average cup abduction angle was similar between groups (DAA 44.2° vs. PA 44.3°, P=.87), but the variance was significantly reduced with the direct anterior approach, P=.02. The use of intraoperative fluoroscopy with the DAA allowed for more accurate cup placement and eliminated severely vertical cups (>55°) seen with the PA.

Aseptic loosening of cobalt chromium monoblock sockets after hip resurfacing.

Acetabular component loosening is a leading cause for revision after metal-on-metal hip resurfacing arthroplasty (MMHRA). We aimed to identify potential risk factors and determine radiographic signs associated with this mode of failure. From a series of 1375 hips treated with MMHRA, 21 (20 patients) underwent revision surgery secondary to aseptic loosening of the acetabular component and 6 patients had a radiographically loose acetabular component. A control group of 27 hips (26 patients) was selected among the patients that did not have a revision, and was matched for age, gender, component size and diagnosis. Mean time to revision in the loosening group was 103.0 months and the mean time of follow-up in the control group was 161.4 months. We found greater activity levels, range of motion scores, and cup abduction angles in the loosening group. The centre-edge (CE) angle of Wiberg was 10° lower in the loosening group compared with the control group. In addition, 11 of the hips from the study group presented a sclerotic halo superior to the cup on the last radiograph vs. none in the control group. There was no difference in the prevalence of postoperative reaming gaps or radiographic signs of neck-cup impingement between the 2 groups. Risk factors for acetabular loosening included hip dysplasia with low CE angle, and a large cup abduction angle. The patient's level of activity influences the appearance of symptoms and the time to revision. We recommend selecting patients with a sufficient CE angle and properly orienting the cup.

Acetabular Cup Abduction Angle Determined by Digital Radiographic Software as Compared to CT-Based Measurement

Aim: Measurement of the acetabular cup orientation is critical in patients after total hip arthroplasty (THA). One important measurement is the acetabular abduction angle. The purpose of the present study was to compare the measurements of the acetabular abduction angle using radiographic analysis software with the measurements made by computed tomography (CT) analysis software. Methods: CT scans and radiograph exams were performed on 150 patients after THA. The acetabular abduction angle was measured from CT using CT-based image analysis software and from radiographs using the dedicated measurement tools of digital radiographic software. Results: The two measurement systems showed no significant difference in the calculation of the acetabular abduction angle (0.35±5.41°; p=0.425) and a moderate correlation was found between the two methods (r=0.619; p<0.001). Discussion: Digital radiographic software provides an accurate and precise measurement of the acetabular abduction angle.

Dual mobility bearings withstand loading from steeper cup-inclinations without substantial wear.

Steep cup abduction angles with adverse joint loading may increase traditional polyethylene bearing wear in total hip arthroplasties. However, there have been few reports evaluating the effect of cup inclination on the wear of dual-mobility devices. In a hip joint simulation, we compared the short-term wear of two-sizes of modular highly cross-linked dual-mobility bearings (28 mm femoral head diameter/42 mm polyethylene insert outer diameter/54 mm acetabular shell diameter; 22.2 mm femoral head diameter/36 mm polyethylene insert outer diameter/48 mm acetabular shell diameter) at 50 and 65° of cup inclination with modular 28 mm femoral head on 54 mm cup diameter metal-on-highly cross-linked polyethylene bearings. Increasing inclination from 50-65° had no changes in volumetric wear of 28/42/54 mm (mean, 1.7 vs. 1.2 mm3 /million cycles, respectively; p = 0.50) and 22.2/36/48 mm (mean, 1.7 vs. 1.2 mm3/million cycles, respectively; p = 0.48) dual mobility bearings. At 65°, 22.2/36/48 mm dual-mobility bearings had lower volumetric loss (mean, 2.2 vs. 6.3 mm(3) ; p = 0.03) and wear rates (mean, 1.2 vs. 2.7 mm3/million cycles; p = 0.02) compared to metal-on-highly cross-linked polyethylene bearings. Modern-generation dual-mobility designs with highly cross-linked polyethylenes may potentially withstand edge-loading from steeper cup-inclinations without substantial decreases in wear.

Effect of cup inclination on predicted contact stress-induced volumetric wear in total hip replacement

In order to increase the lifetime of the total hip endoprosthesis, it is necessary to understand mechanisms leading to its failure. In this work, we address volumetric wear of the artificial cup, in particular the effect of its inclination with respect to the vertical. Volumetric wear was calculated by using mathematical models for resultant hip force, contact stress and penetration of the prosthesis head into the cup. Relevance of the dependence of volumetric wear on inclination of the cup (its abduction angle ϑA) was assessed by the results of 95 hips with implanted endoprosthesis. Geometrical parameters obtained from standard antero-posterior radiographs were taken as input data. Volumetric wear decreases with increasing cup abduction angle ϑA. The correlation within the population of 95 hips was statistically significant (P = 0.006). Large cup abduction angle minimises predicted volumetric wear but may increase the risk for dislocation of the artificial head from the cup in the one-legged stance. Cup abduction angle and direction of the resultant hip force may compensate each other to achieve optimal position of the cup with respect to wear and dislocation in the one-legged stance for a particular patient.

Changes of Load Distribution on Cup-Bone Interface at the Different Positions of Non-Cemented Acetabular Cup

Objective To explore the relationship between acetabular cup position and the load distribution within the acetabulum and to confirm an optimal range of cup position, thereby providing a theoretical criterion from a biomechanical aspect for proper cup implantation in clinical work. Methods A male adult cadaveric pelvic was scanned with spiral CT, and then the two-dimensional images were evaluated using GE medical systems software and the outline of the pelvis was identified by the edge detective estimation. Pelvic coordinate data were put into the computer to build up a three-dimensional (3D) finite element model of the pelvic using Solidworks software . A φ48 non-cemented cup from Tianjin Huabei Medical Instrument Factory was used, and the 3D measurement of the cup was carried out by CLY single-arm 3D measurement apparatus, which was made in Testing Technology Institute of China. The measurement data were transferred into computer. Through the CAD Sliod Works 2010 software, the 3D model of the cup was automatically reconstructed. After wards, one-foot standing position was simulated to conduct the loading and constraint of the model, the Mises and shear force distributing of the cup were analyzed, forecasting the mechanical risk of prosthetic failure. Results In the 3D finite element model of human pelvis, the number of total nodes was 103043 and the number of total elements was 69271. Abduction angle did not affect the Mises and shear force distributions between the range of 40°-50°(P&gt;0.05). However, significant affects appeared in Mises and shear force once the abduction angle was &lt; 35° or &gt; 50°. The change of the cup anteversion within5°-30°would not affect the Mises and shear forces in the acetabulum (P &gt; 0.05). Conclusion A uniform load distribution on the cup-bone interface can be obtained when the cup abduction angle is from 40°to 50°. The change of the cup anteversion angle can not affect the load distribution in the acetabulum, therefore the cup abduction range of 40°-50°can be confirmed as the safe range for cup implantation.

Meta-analysis of the Incidence and Risk Factors for Squeaking after Primary Ceramic-on-ceramic Total Hip Arthroplasty in Asian Patients.

PurposeThe purpose of this study was to assess the squeaking incidence and risk factors after primary ceramic-on-ceramic total hip arthroplasty (THA) in Asian patients using meta-analysis.Materials and MethodsWe performed a meta-analysis of published data on the squeaking incidence and risk factors from 2000 to 2013. Eight studies in Asians were analyzed for both squeaking incidence and risk factors and 25 studies in Western patients were analyzed for squeaking incidence. The data collected were: patient factors, surgical factors and implantation factors.ResultsThe overall incidence of hip squeaking was 2.7% in Asians and 3.1% in Westerners. This difference was not statistically significant. The only significant risk factor was an increase in the acetabular cup abduction angle. Of the factors, the cup abduction angle was the only significant risk factor for the occurrence rate of squeaking, and the occurrence rate tended to increase with increasing angle.ConclusionThe incidence of squeaking in Asians after primary ceramic-on-ceramic THA is 2.7% and is similar to that in Westerners. The increased cup abduction angle is associated with squeaking; therefore, surgeons should be careful not to implant the cup at a too steep abduction angle.