Precision of GE Lunar iDXA for the Measurement of Total and Regional Body Composition in Nonobese Adults

Dual-energy X-ray absorptiometry (DXA) is a well-accepted technique for measuring body composition. Knowledge of measurement precision is critical for monitoring of changes in bone mineral content (BMC), and fat and lean masses. The purpose of this study was to characterize in vivo precision of total body and regional body composition parameters using the GE Lunar iDXA (GE Healthcare Lunar, Madison, WI) system in a sample of nonobese subjects. We also evaluated the difference between expert and automatic region-of-interest (ROI) analysis on body composition precision. To this end, 2 total body scans were performed on each subject with repositioning between scans. Total body precision for BMC, fat and lean mass were 0.5%, 1.0%, and 0.5% coefficient of variation (CV), respectively. Regional body composition precision error was less than 2.5% CV for all regions except arms. Precision error was higher for the arms (CV: BMC 1.5%; fat mass 2.8%; lean mass 1.6%), likely owing to the placement of arms relative to torso leading to differences in ROI. There was a significant correlation between auto ROI and expert ROI (r > 0.99). Small, but statistically significant differences were found between auto and manual ROI. Differences were small in total body, leg, trunk, and android and gynoid regions (0.004–2.8%), but larger in arm region (3.0–6.3%). Total body and regional precision for iDXA are small and it is suggested that iDXA may be useful for monitoring changes in body composition during longitudinal trials.     

A Cross-Calibration Study of GE Lunar iDXA and GE Lunar DPX Pro for Body Composition Measurements in Children and Adults

Objective: To cross-calibrate dual energy X-ray absorptiometry machines when replacing GE Lunar DPX-Pro with GE Lunar iDXA. Methods: A cross-sectional study was conducted in 126 children (3–19 years) and 135 adults (20–66 years). Phantom cross calibration was carried out using aluminum phantom provided with each of the machines on both machines. Total body less head (TBLH), lumbar spine (L2–L4) and left femoral neck bone mineral density (BMD), bone mineral content (BMC), and bone area were assessed for each patient on both machines. TBLH lean and fat mass were also measured. Bland-Altman analysis, linear regressions, and independent sample t test were performed to evaluate consistency of measurements and to establish cross-calibration equations. Results: iDXA measured 0.33% lower BMD and 0.64% lower BMC with iDXA phantom as compared to DPX-Pro phantom (p < 0.001). In children, TBLH-BMC, femoral BMC and area were measured 10%–14% lesser, TBLH area was higher by 1%–2% and L2–L4 area by 10%–14% by iDXA as compared to DPX-Pro. iDXA measured higher TBLH fat [15% (girls), 31% (boys)] than DPX-Pro. In adults, TBLH-BMD (1.7%–3.4%), BMC (6.0%–10.9%) and area (4.2%–7.6%) were measured lesser by iDXA than DPX-Pro. L2–L4 BMD was higher [2.7% (men), 1.8% (women)] by iDXA than DPX-Pro. Femoral BMC was 2.11% higher in men and 4.1% lower in women by iDXA as compared to DPX-Pro. In children, R² of cross-calibration equations, ranged from 0.91 to 0.96; in adults, it ranged from 0.93 to 0.99 (p < 0.01). After the regression equations were applied, differences in BMD values between both machines were negligible. Conclusion: A strong agreement for bone mass and body composition was established between both machines. Cross-calibration equations need to be applied to transform DPX-Pro measurements into iDXA measurements to avoid errors in assessment. This study documents a need for use of cross-calibration equations to transform DPX-Pro body composition data into iDXA values for clinical diagnosis.     

Cross Calibration of the GE Prodigy and iDXA for the Measurement of Total and Regional Body Composition in Adults

Dual-energy X-ray absorptiometry (DXA) body composition measurements are widely performed in both clinical and research settings, and enable the rapid and noninvasive estimation of total and regional fat and lean mass tissues. DXA upgrading can occur during longitudinal monitoring or study; therefore, cross calibration of old and new absorptiometers is required. We compared soft tissue estimations from the GE Prodigy (GE Healthcare, Madison, WI) with the more recent iDXA (GE Healthcare) and developed translational equations to enable Prodigy values to be converted to iDXA values. Eighty-three males and females aged 20.1–63.3?yr and with a body mass index range of 17.0–34.4?kg/m² were recruited for the study. Fifty-nine participants (41 females and 18 males) comprised the cross-calibration group and 24 (14 females and 10 males) comprised the validation group. Total body Prodigy and iDXA scans were performed on each subject within 24?h. Predictive equations for total and regional soft tissue parameters were derived from linear regression of the data. Measures of lean and fat tissues were highly correlated (R²?=?0.95–0.99), but significant differences and variability between machines were identified. Bland-Altman analysis revealed significant biases for most measures, particularly for arm, android, and gynoid fat mass (12.3%–22.7%). The derived translational equations reduced biases and differences for most parameters, although limits of agreement exceeded iDXA least significant change. In conclusion, variability in soft tissue estimates between the Prodigy and iDXA were detected, supporting the need for translational equations in longitudinal monitoring. The derived equations are suitable for group analysis but not individual analysis.     

Cross Calibration of Hologic QDR2000 and GE Lunar Prodigy for Whole Body Bone Mineral Density and Body Composition Measurements

The objective of this study was to undertake an in vivo cross calibration of body composition, whole body bone mineral content (BMC) and bone mineral density (BMD) between a Hologic QDR2000 and a GE Healthcare Lunar Prodigy. Twenty-one subjects attending for routine bone densitometry were recruited to the study (19 female and 2 male, aged 30–79 yr). Phantom cross calibrations were carried out using the Bio-Imaging Variable Composition Phantom (VCP) for percentage fat (%fat) and the Bona Fide Phantom (BFP) for BMD. There was no significant difference in whole body lean body mass between the QDR2000 and the Prodigy. Fat mass (FM) and %fat were significantly higher on the QDR2000. BMC and whole body BMD were significantly higher on Prodigy. As the BMC increased, so did the difference between the 2 instruments. The VCP did not provide an adequate cross calibration of %fat compared with in vivo. The BFP provided a good cross calibration of whole body BMD compared with in vivo. The results suggest that the partitioning of the soft tissue component between lean and fat in the 2 instruments is systematically different. The variation between instruments from the same and different manufacturers reported in the literature varies widely, as does the comparison with criterion methods. This makes it difficult to generalize the results of this study to other centers and it is recommended that each center would have to cross calibrate when changing equipment.     

In Vivo Precision of the GE Lunar iDXA for the Assessment of Lumbar Spine,Total Hip,Femoral Neck,and Total Body Bone Mineral Density in Severely Obese Patients

No study has evaluated the precision of the GE Lunar iDXATM (GE Healthcare) in measuring bone mineral density (BMD) among severely obese patients. The purpose of the study was to evaluate the precision of the GE Lunar iDXATM for assessing BMD, including the lumbar spine L1–L4, L2–L4, the total hip, femoral neck, and total body in a severely obese population (body mass index [BMI] > 40 kg/m²). Sixty-four severely obese participants with a mean age of 46 ± 11 yr, BMI of 49 ± 6 kg/m², and a mean body mass of 136.8 ± 20.4 kg took part in this investigation. Two consecutive iDXA scans (with repositioning) of the total body (total body BMD [TBBMD]), lumbar spine (L1–L4 and L2–L4), total hip (total hip BMD [THBMD]), and femoral neck (femoral neck BMD [FNBMD]) were conducted for each participant. The coefficient of variation (CV), the root mean square (RMS) averages of standard deviations of repeated measurements, the corresponding 95% least significant change, and intraclass correlations (ICCs) were calculated. In addition, analysis of bias and coefficients of repeatability were calculated. The results showed a high level of precision for total body (TBBMD), lumbar spine (L1–L4), and total hip (THBMD) with values of RMS: 0.013, 0.014, and 0.011 g/cm²; CV: 0.97%, 1.05%, and 0.99%, respectively. Precision error for the femoral neck was 2.34% (RMS: 0.025 g/cm²) but still represented high reproducibility. ICCs in all dual-energy X-ray absorptiometry measurements were 0.99 with FNBMD having the lowest at 0.98. Coefficients of repeatability for THBMD, FNBMD, L1–L4, L2–L4, and TBBMD were 0.0312, 0.0688, 0.0383, 0.0493, and 0.0312 g/cm², respectively. The Lunar iDXA demonstrated excellent precision for BMD measurements and is the first study to assess reproducibility of the GE Lunar iDXA with severely obese adults.     

Quantification of Scan Analysis Errors in GE Lunar DXA Visceral Adiposity in Adults

Utilization of dual-energy X-ray absorptiometry is increasing in clinical settings and the fitness industry as a viable tool to assess total and regional body composition, including visceral adiposity. Previous research using small samples (<50) has described several pitfalls in patient positioning, scan acquisition, and/or analysis that alter regional body composition values. Our aim was to quantify the largest probable error in measures of total, android, gynoid, and visceral fat caused by incorrect placement of the head cut-line, in a large sample of adults. Total body images (N = 436) from 196 women and 67 men (20–85 years) scanned on a GE Lunar Prodigy densitometer were analyzed using enCORE software in 2 ways: (1) placing the head cut-line just beneath the bony protuberance of the chin according to manufacturer recommendation (correct method); (2) placing the head cut-line at the lowest point below the chin and just above the soft tissue at the shoulders (incorrect method). All other cut-lines were fixed. Mean differences in adiposity were examined using Lin's concordance correlation coefficient; equality of means and variances were evaluated using Bradley-Blackwood F-tests. The limits of agreement were displayed as Bland-Altman plots and calculated as the mean difference ±1.96 times the standard deviation of the difference. Correlation coefficients for paired comparisons of adiposity for correct vs incorrect cut-line placement ranged from 0.983–0.999 for all variables (all p < 0.001). Significant mean differences were 172 ± 130, 201 ± 168, 65 ± 122, and ?143 ± 336 g for android, gynoid, visceral, and total fat mass, respectively (all p < 0.0001). These differences exceeded our site's least significant change in 66%, 37%, 29%, and 4% of participant scans for android, gynoid, visceral, and total fat mass, respectively. Our findings underscore the importance of careful review of the manufacturer's auto analysis and consistency in conducting serial scans to ensure accurate and precise measures of regional body fat.     

Same-Day Vs Consecutive-Day Precision Error of Dual-Energy X-Ray Absorptiometry for Interpreting Body Composition Change in Resistance-Trained Athletes

The application of dual-energy X-ray absorptiometry (DXA) in sport science settings is gaining popularity due to its ability to assess body composition. The International Society for Clinical Densitometry (ISCD) recommends application of the least significant change (LSC) to interpret meaningful and true change. This is calculated from same-day consecutive scans, thus accounting for technical error. However, this approach does not capture biological variation, which is pertinent when interpreting longitudinal measurements, and could be captured from consecutive-day scans. The aims of this study were to investigate the impact short-term biological variation has on LSC measures, and establish if there is a difference in precision based on gender in a resistance-trained population. Twenty-one resistance-trained athletes (age: 30.6 ± 8.2 yr; stature: 174.2 ± 7.2 cm; mass: 74.3 ± 11.6 kg) with at least 12 mo consistent resistance training experience, underwent 2 consecutive DXA scans on 1 d of testing, and a third scan the day before or after. ISCD-recommended techniques were used to calculate same-day and consecutive-day precision error and LSC values. There was high association between whole body (R²?=?0.98–1.00) and regional measures (R²?=?0.95–0.99) for same-day (R²?=?0.98–1.00), and consecutive-day (R²?=?0.95–0.98) measurements. The consecutive-day precision error, in comparison to same-day precision error, was significantly different (p < 0.05), and almost twice as large for fat mass (1261 g vs 660 g), and over 3 times as large for lean mass (2083 g vs 617 g), yet still remained within the ISCD minimum acceptable limits for DXA precision error. No whole body differences in precision error were observed based on gender. When tracking changes in body composition, the use of precision error and LSC values calculated from consecutive-day analysis is advocated, given this takes into account both technical error and biological variation, thus providing a more accurate indication of true and meaningful change.     

In vivo Precision of the GE Lunar iDXA Densitometer for the Measurement of Total-Body, Lumbar Spine, and Femoral Bone Mineral Density in Adults

Knowledge of precision is integral to the monitoring of bone mineral density (BMD) changes using dual-energy X-ray absorptiometry (DXA). We evaluated the precision for bone measurements acquired using a GE Lunar iDXA (GE Healthcare, Waukesha, WI) in self-selected men and women, with mean age of 34.8 yr (standard deviation [SD]: 8.4; range: 20.1–50.5), heterogeneous in terms of body mass index (mean: 25.8 kg/m²; SD: 5.1; range: 16.7–42.7 kg/m²). Two consecutive iDXA scans (with repositioning) of the total body, lumbar spine, and femur were conducted within 1 h, for each subject. The coefficient of variation (CV), the root-mean-square (RMS) averages of SDs of repeated measurements, and the corresponding 95% least significant change were calculated. Linear regression analyses were also undertaken. We found a high level of precision for BMD measurements, particularly for scans of the total body, lumbar spine, and total hip (RMS: 0.007, 0.004, and 0.007 g/cm²; CV: 0.63%, 0.41%, and 0.53%, respectively). Precision error for the femoral neck was higher but still represented good reproducibility (RMS: 0.014 g/cm²; CV: 1.36%). There were associations between body size and total-body BMD and total-hip BMD SD precisions (r = 0.534–0.806, p < 0.05) in male subjects. Regression parameters showed good association between consecutive measurements for all body sites (r² = 0.98–0.99). The Lunar iDXA provided excellent precision for BMD measurements of the total body, lumbar spine, femoral neck, and total hip.     

Precision Errors,Least Significant Change,and Monitoring Time Interval in Pediatric Measurements of Bone Mineral Density,Body Composition,and Mechanostat Parameters by GE Lunar Prodigy

Dual-energy X-ray absorptiometry (DXA) method is widely used in pediatrics in the study of bone density and body composition. However, there is a limit to how precise DXA can estimate bone and body composition measures in children. The study was aimed to (1) evaluate precision errors for bone mineral density, bone mass and bone area, body composition, and mechanostat parameters, (2) assess the relationships between precision errors and anthropometric parameters, and (3) calculate a “least significant change” and “monitoring time interval” values for DXA measures in children of wide age range (5–18 yr) using GE Lunar Prodigy densitometer. It is observed that absolute precision error values were different for thin and standard technical modes of DXA measures and depended on age, body weight, and height. In contrast, relative precision error values expressed in percentages were similar for thin and standard modes (except total body bone mineral density [TBBMD]) and were not related to anthropometric variables (except TBBMD). Concluding, due to stability of percentage coefficient of variation values in wide range of age, the use of precision error expressed in percentages, instead of absolute error, appeared as convenient in pediatric population.     

Effect of Chemotherapy on Dual-Energy X-ray Absorptiometry (DXA) Body Composition Precision Error in Head and Neck Cancer Patients

Background: Precision error in dual-energy X-ray absorptiometry (DXA) is defined as difference in results due to instrumental and technical factors given no biologic change. The aim of this study is to compare precision error in DXA body composition scans in head and neck cancer patients before and 2 months after chemotherapy. Methodology: A total of 34 male head and neck cancer patients with normal body mass index (BMI) were prospectively enrolled and all patients received 2 consecutive DXA scans both before and after 2 months of chemotherapy for a total of 4 scans. The precision error of 3 DXA body composition values (lean mass, fat mass, and bone mineral content) was calculated for total body and 5 body regions (arms, legs, trunk, android, and gynoid). Precision errors before and after treatment were compared using generalized estimating equation model. Results: There was no significant change in precision error for the DXA total body composition values following chemotherapy; lean mass (0.33%–0.40%, p = 0.179), total fat mass (1.39%–1.70%, p = 0.259) and total bone mineral content (0.42%–0.56%, p = 0.243). However, there were significant changes in regional precision error; trunk lean mass (1.19%–1.77%, p = 0.014) and android fat mass (2.17%–3.72%, p = 0.046). Conclusions: For head and neck cancer patients, precision error of DXA total body composition values did not change significantly following chemotherapy; however, there were significant changes in fat mass in the android and lean mass in the trunk. Caution should be exercised when interpreting longitudinal DXA body composition data in those body parts.     

Interpretation of Dual-Energy X-Ray Absorptiometry-Derived Body Composition Change in Athletes: A Review and Recommendations for Best Practice

Dual-energy X-ray absorptiometry (DXA) is a medical imaging device which has become the method of choice for the measurement of body composition in athletes. The objectives of this review were to evaluate published longitudinal DXA body composition studies in athletic populations for interpretation of “meaningful” change, and to propose a best practice measurement protocol. An online search of PubMed and CINAHL via EBSCO Host and Web of Science enabled the identification of studies published until November 2016. Those that met the inclusion criteria were reviewed independently by 2 authors according to their methodological quality and interpretation of body composition change. Twenty-five studies published between 1996 and November 2016 were reviewed (male athletes: 13, female athletes: 3, mixed: 9) and sample sizes ranged from n?=?1 to 212. The same number of eligible studies was published between 2013 and 2016, as over the 16?yr prior (between 1996 and 2012). Seven did not include precision error, and fewer than half provided athlete-specific precision error. There were shortfalls in the sample sizes on which precision estimates were based and inconsistencies in the level of pre-scan standardization, with some reporting full standardization protocols and others reporting only single (e.g., overnight fast) or no control measures. There is a need for standardized practice and reporting in athletic populations for the longitudinal measurement of body composition using DXA. Based on this review and those of others, plus the official position of the International Society for Clinical Densitometry, our recommendations and protocol are proposed as a guide to support best practice.     

Pediatric in vivo cross-calibration between the GE Lunar Prodigy and DPX-L bone densitometers

Dual energy x-ray absorptiometry (DXA) machine cross-calibration is an important consideration when upgrading from old to new technology. In a recent cross-calibration study using adult subjects, close agreement between GE Lunar DPX-L and GE Lunar Prodigy scanners was reported. The aim of this work was to cross-calibrate the two machines for bone and body composition parameters for pediatrics from age 5 years onwards. One-hundred ten healthy volunteers aged 5–20 years had total body and lumbar spine densitometry performed on DPX-L and Prodigy densitometers. Cross-calibration was achieved using linear regression and Bland–Altman analysis. There was close agreement between the machines, with r² ranging from 0.85 to 0.99 for bone and body composition parameters. Paired t-tests demonstrated significant differences between machines that were dependent on scan acquisition mode, with the greatest differences reported for the smallest children. At the lumbar spine, Prodigy bone mineral density (BMD) values were on average 1.6% higher compared with DPX-L. For the total body, there were no significant differences in BMD; however, there were significant differences in bone mineral content (BMC) and bone area. For small children, the Prodigy measured lower BMC (9.4%) and bone area (5.8%), whereas for larger children the Prodigy measured both higher BMC (3.1%) and bone area (3.0%). A similar contrasting pattern was also observed for the body composition parameters. Prodigy values for lean body mass were higher (3.0%) for small children and lower (0.5%) for larger children, while fat body mass was lower (16.4%) for small children and higher (2.0%) for large children. Cross-calibration coefficients ranged from 0.84 to 1.12 and were significantly different from 1 (p<0.0001) for BMC and bone area. Bland–Altman plots showed that within the same scan acquisition modes, the magnitude of the difference increased with body weight. The results from this study suggest that the differences between machines are mainly due to differences in bone detection algorithms and that they vary with body weight and scan mode. In general, for population studies the differences are not clinically significant. However, for individual children being measured longitudinally, cross-over scanning may be required.     

Effect of Hand Positioning on DXA Total and Regional Bone and Body Composition Parameters,Precision Error,and Least Significant Change

Dual-energy X-ray absorptiometry (DXA) body composition measurements are performed in both clinical and research settings for estimations of total and regional fat mass, lean tissue mass, and bone mineral content. Subject positioning influences precision and positioning instructions vary between manufacturers. The aim of the study was to determine the effect of hand position and scan mode on regional and total body bone and body composition parameters and determine protocol-specific body composition precision errors. Thirty-eight healthy subjects (men; mean age: 27.1?±?12.1?yr) received 4 consecutive total body GE-Lunar iDXA (enCORE v 15.0) scans with re-positioning, and scan mode was dependent on body size. Twenty-three subjects received scans in standard mode and 15 received scans in thick scan modes. Two scans per subject were conducted with subject hands prone and 2 with hands mid-prone. The precision error (root mean squared standard deviation; percentage coefficient of variation) and least significant change for each protocol were determined using the International Society for Clinical Densitometry calculator. Hands placed in the mid-prone position increased arm bone mineral density (BMD) (standard mode: 0.185?g*cm^?2, thick mode: 0.265?g*cm^?2; p?<?0.05), total body BMD (standard mode: 0.051?g*cm^?2, thick mode: 0.069?g*cm^?2; p?<?0.001), and total body BMD Z-score (standard mode: 0.5. thick mode: 0.7; p?<?0.001). This was due to reductions in bone area and bone mineral content. In standard mode, hands mid-prone reduced fat mass (0.05?kg, p?<?0.05) and increased lean mass (0.11?kg, p?<?0.05). There were no differences in body composition for thick mode scans. Hands mid-prone reduced lean mass precision error at the arms, trunk, and total body (p?<?0.01). DXA clinical and research centers are advised to maintain consistency in their hand positioning and scan mode protocols, and consideration should be given to the hand positioning used for reference data. As a best practice recommendation, published DXA-based studies and reports for clinic-based total body assessments should ensure that subject positioning is fully described.     

Vertebral Morphometry: Repeat Scan Precision Using the Lunar Expert-XL and the Hologic 4500A. A Study for the “WISDOM” RCT of Hormone Replacement Therapy

On radiation safety grounds there is concern about the morbidity attributable to routine radiographs of the spine for the identification of new fractures in large-scale trials of fracture prevention. However, the role of the potentially safer low-radiation-dose technique of vertebral morphometry performed by third generation dual-energy X-ray absorptiometry equipment requires evaluation for use in clinical trials. We have therefore investigated the short-term inter-scan imprecision as well as the imprecision attributable to different-day analyses by the same operator and differences in analyses by different operators. The volunteer subjects were participants in a pilot study for a randomized controlled trial of hormone replacement therapy (Women”s International Study of long Duration Oestrogen after Menopause, WISDOM). Each subject had two morphometric X-ray analysis scans separated by 2–4 weeks. Exclusions were women with densitometrically defined osteoporosis, as defined by the WHO criterion, and women with a body mass index exceeding 30.9 kg/m². On average, the women were 58.7 years of age and had bone mineral density values in the lumbar spine which were about 0.7 SD units higher than a reference US female age-matched population. Scans were assessed from vertebrae T7 through L4. In the study there were no clinically significant differences in performance between the Hologic QDR 4500A and the Lunar Expert XL equipment. Between-scan imprecision was significantly worse than imprecision attributable to reanalysis of the same scan by a different operator or the same operator after an interval. Vertebral level had an effect on measurement uncertainty, especially at the level of the diaphragm and at T7. Coefficients of variation, expressed as percentages of mean values, were better for absolute height measurements than for height ratios, ranging from 1.75% to 3.40% for the three heights measured on three separate machines and from 2.34% to 4.11% for the two height ratios. These results compared favorably with the equivalent figures from a parallel study of morphometry precision undertaken using standard lateral radiographs of the thoracic and lumbar spine (3.1–3.6% and 3.8–3.9%, respectively). We conclude that in trials of prevention therapy in women (or men) selected for not having osteoporosis, low-dose vertebral morphometry using the Hologic 4500A, the Lunar Expert XL or similar equipment is preferable on safety grounds to the classical technique based on standard radiographs, although conventional radiology may still be required in those with prevalent or incident deformities to exclude causes other than osteoporosis. The place of this low-dose technique in trials performed on patients with osteoporosis requires further study. Received: 29 June 1999 / Accepted: 15 December 1999     

Two Year Clinical Outcomes of Total Hip Arthroplasty Are Not Dependent on Femoral Head Composition

BackgroundAssessment of clinical outcomes and patient quality of life after total hip arthroplasty continues to grow in importance with the focus on how bearing surfaces affect long-term survival, wear, and cost. Further, as quality measures have become incorporated into reimbursement, there is a need to quantify factors which may influence these outcomes. Currently, there is a paucity of literature regarding the effects of the femoral head composition on clinical outcomes or quality of life.Questions/PurposesWe sought to determine if any difference in quality of life measures could be detected in patients treated with total hip replacement implanted with cobalt-chrome (CoCr) versus ceramic femoral heads at 2-year follow-up.MethodsWe compared the hip disability and osteoarthritis outcome score (HOOS) and EuroQOL (EQ5D) scores of a matched set of patients that underwent primary total hip arthroplasty with highly cross-linked polyethylene (HXLPE) and a single implant system consisting of either a metal or a ceramic femoral head.ResultsClinical outcomes and quality of life improved for both groups after hip replacement surgery. Patients with a ceramic head showed greater improvement than those with a metal head in HOOS pain and EQ5D VAS scores by a statistically significant margin (p = 0.0417 and 0.019, respectively), but the differences between the HOOS and EQ5D VAS scores (3.4 and 0.04, respectively) do not demonstrate a clinically significant difference.ConclusionsWe found that the femoral head composition has no effect on clinical outcomes or patient quality of life at 2 years.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-015-9433-0) contains supplementary material, which is available to authorized users.