共查询到20条相似文献，搜索用时 31 毫秒
1.
Michael T. Milone Ran Schwarzkopf Patrick A. Meere Kaitlin M. Carroll Seth A. Jerabek Jonathan Vigdorchik 《The Journal of arthroplasty》2017,32(6):1890-1893
Background
To our knowledge, no study has assessed the ability of rigid patient positioning devices to afford arthroplasty surgeons with ideal acetabular orientation throughout surgery. The purpose of this study is to use robotic arm–assisted computer navigation to assess the reliability of pelvic position in total hip arthroplasty performed on patients positioned with rigid positioning devices.Methods
A prospective cohort of 100 hips (94 patients) underwent robotic-guided total hip arthroplasty in the lateral decubitus position from the posterior approach, 77 stabilized by universal lateral positioner, and 23 by peg board. Before reaming, computed tomography–templated computer software generated true values of pelvic anteversion and inclination based on the position of the robot arm registered to the patient’s preoperative pelvic computed tomography.Results
Mean alteration in anteversion and inclination values was 1.7° (absolute value, 5.3°; range, ?20° to 20°) and 1.6° (absolute value, 2.6°; range, ?8° to 10°), respectively. And 22% of anteversion values were altered by >10° and 41% by >5°. There was no difference between hip positioners used (P = .36). Anteversion variability was correlated with body mass index (P = .02).Conclusion
Despite the use of rigid patient positioning devices—a lateral hip positioner or peg board—this study reveals clinically important malposition of the pelvis in many cases, especially with regard to anteversion. These results show a clear need to pay particular attention to anatomic landmarks or computer-assisted techniques to assure accurate acetabular cup positioning. Patient positioning should not be solely trusted. 相似文献2.
Keisuke Uemura Masaki Takao Yoshito Otake Koki Koyama Futoshi Yokota Hidetoshi Hamada Takashi Sakai Yoshinobu Sato Nobuhiko Sugano 《The Journal of arthroplasty》2017,32(8):2568-2573
Background
Cup anteversion and inclination are important for avoiding implant impingement and dislocation in total hip arthroplasty. However, functional cup anteversion and cup inclination also change as the pelvic sagittal inclination (PSI) changes. Therefore, PSI in both supine and standing positions was measured in a large cohort in this study.Methods
A total of 422 patients (median age, 61; range, 15-87) who underwent total hip arthroplasty were the subjects of this study. There were 83 patients with primary osteoarthritis (OA), 274 patients with developmental dysplasia–derived secondary OA, 48 patients with osteonecrosis, and 17 patients with rapidly destructive coxopathy (RDC). Preoperative PSI in supine and standing positions was measured by automated computed topography segmentation and landmark localization of the pelvis followed by intensity-based 2D-3D registration, and the number of cases in which PSI changed more than 10° posteriorly was calculated. Hip disease, sex, and age were analyzed if they were related to a PSI change of more than 10°.Results
The median PSI was 5.1° (interquartile range, 0.4°-9.4°) in supine and ?1.3° (interquartile range, ?6.5° to 4.2°) in standing position. There were 79 cases (19%) in which the PSI changed more than 10° posteriorly from supine to standing. Elder age and patients with primary OA and RDC were revealed to be the related factors.Conclusion
PSI changed more than 10° posteriorly from supine to standing in 19% of cases. Age and diagnosis of primary OA and RDC were the significant factors for the posterior rotation. 相似文献3.
Satoru Tamura Shunsaku Nishihara Masaki Takao Takashi Sakai Hidenobu Miki Nobuhiko Sugano 《The Journal of arthroplasty》2017,32(3):877-882
Background
Functional anteversion and inclination of the cup change as the pelvic sagittal inclination (PSI) changes. The purposes of this study were to investigate the chronological changes of PSI during a 10-year follow-up period after total hip arthroplasty (THA) and to report the characteristics of patients who showed a greater than 10° change in the PSI from the supine to the standing position.Methods
The subjects were 70 patients who were followed up for 10 years after THA. PSI values in the supine and standing positions were measured by 2D-3D matching using computed tomography images and pelvic radiographs. PSI values before THA and 1, 5, and 10 years after THA were compared in both the supine and standing positions.Results
Supine PSI showed less than 5° of change, whereas standing PSI showed a significant decrease with time over the 10-year period. Although 43% of patients with less than 10° of difference in the PSI between the supine and standing positions before THA increased PSI posteriorly (reclining) more than 10° in standing from the supine position at 10 years, no late dislocation was observed.Conclusion
Supine PSI showed no significant change, but standing PSI showed a significant increase posteriorly with time over a 10-year period. However, this PSI change did not reach the level that it caused negative consequences such as late dislocation. The pelvic position in the supine position might still be a good functional reference position of the pelvis for aiming to achieve proper cup alignment at 10 years. 相似文献4.
Melissa C. Soderquist Ryan Scully Anthony S. Unger 《The Journal of arthroplasty》2017,32(9):2748-2754
Background
Acetabular cup placement in total hip arthroplasty (THA) has been recognized as an important factor in operative success, and accurate cup placement has been the impetus for novel medical technologies.Methods
This article examines the cup placement in 955 THAs using a freehand Direct Anterior Approach on a standard operating table. Acetabular anteversion and inclination were determined using the circle theorem. Measurements were divided into safe zone placement determined by Callanan et al as 5°-25° for anteversion and 30°-45° for inclination, as well as by Lewinnek et al as 5°-25° for anteversion and 30°-50° for inclination. Dislocation rate was determined and correlated to safe zone placement.Results
Although technology has advanced for cup placement, this investigation shows that a freehand technique demonstrates 0.31% dislocation after THA with an accuracy of 85% for the Lewinnek safe zone and 61% for Callanan, potentially because of the sparing of the posterior hip capsule.Conclusion
The direct anterior approach to the hip on a regular operating table is safe and reliable. Our results demonstrate improvement in cup positioning compared with other freehand techniques. Surgeon awareness and control of the position of the pelvis within space optimizes acetabular component accuracy and precision without the need for special equipment, such as intraoperative fluoroscopy. 相似文献5.
Jean Y. Lazennec Ian C. Clark Dominique Folinais Imen N. Tahar Aidin E. Pour 《The Journal of arthroplasty》2017,32(10):3184-3190
Background
This study used EOS imaging of primary total hip arthroplasty (THA) patients, with and without predating spinal fusion, to investigate (1) the impact of spinal fusion on acetabular implant anteversion and inclination, and (2) whether more extensive spinal fusion (fusion starting above the thoracolumbar junction or extension of fusion to the sacrum) affects acetabular implant orientation differently than lumbar only spinal fusion.Methods
Ninety-three patients had spinal fusion (case group), and 150 patients were without spinal fusion (controls). None of the patients experienced dislocation. The change in sacral slope (SS) and cup orientation from standing to sitting was measured.Results
Mean SS change from the standing to sitting positions was ?7.9°in the fusion group vs ?18.4°in controls (P = .0001). Mean change in cup inclination from the standing to sitting positions was 4.9°in the fusion group vs 10.2°in controls (P = .0001). Mean change in cup anteversion from standing to sitting positions was 7.1°in the fusion group vs 12.1°in controls (P = .0001). For each additional level of spinal fusion, the change in SS from standing to sitting positions decreased by 1.6(95% confidence interval [CI], 2.2073-1.0741), the change in cup inclination decreased by 0.8(95% CI, 0.380-1.203), and the change in cup anteversion decreased by 0.9(95% CI, 0.518-1.352; P < .001 in all cases).Conclusion
Patients with spinal fusion demonstrated less adaptability of the lumbosacral junction. Longer spinal fusion or inclusion of the pelvis in the fusion critically impacts hip-spine biomechanics and significantly affects the ability to compensate in the standing-to-sitting transition. 相似文献6.
Friedrich Boettner Matthieu Zingg Ahmed K. Emara Wenzel Waldstein Martin Faschingbauer Maximilian F. Kasparek 《The Journal of arthroplasty》2017,32(4):1180-1185
Background
This study compares the differences in acetabular component position, leg length discrepancy, and hip offset between the anterior and posterior approach. A novel method is applied to determine the acetabular anteversion using the C-arm tilt angle for the anterior approach.Methods
Hundred consecutive anterior total hip arthroplasties were matched according to gender, body mass index, and age to a cohort of 100 primary total hip arthroplasties operated on through a posterior approach. Postoperative radiographs were analyzed to determine cup inclination, cup anteversion, leg length discrepancy, and hip offset.Results
The mean inclination was 40.8° (range 33°-48°) and 45.1° (range 33°-55°) for the anterior and posterior approach, respectively. Using the new C-arm tilt plane technique, an average acetabular anteversion of 18.4° (range 11°-26°) was achieved with the anterior approach compared with 23.6° (range 8°-38°) with the posterior approach. Hundred percent cups in the anterior group and 81% in the posterior group fell within the safe zone (P < .001). There was no difference in the overall hip offset between the operated side and the contralateral side for the anterior (P = .074) and posterior (P = .919) group. There was no difference in leg length discrepancy between the 2 approaches (P = .259).Conclusion
Intraoperative fluoroscopy-assisted direct anterior approach was associated with improved acetabular component positioning. However, no benefit was shown with regards to restoration of hip offset or leg length. 相似文献7.
Denis Nam Venessa Riegler John C. Clohisy Ryan M. Nunley Robert L. Barrack 《The Journal of arthroplasty》2017,32(4):1200-1205
Background
This study's purpose was to determine the impact of THA implantation on pelvic motion, and to assess motion in patients with a history of lumbar fusion or prosthetic dislocation.Methods
This was an IRB-approved, prospective investigation of 3 cohorts: (1) patients without a history of lumbar surgery undergoing THA (group A), (2) patients with a lumbar fusion (group B), and (3) patients with a THA prosthetic dislocation (group C). All patients received both standing and sitting lateral pelvis images to measure sacral slope and pelvic tilt in the sagittal plane.Results
Fifty-eight patients were enrolled (24 group A, 27 group B, and 7 group C), with no differences in age, gender, or body mass index (P = .1-.7). In group A, the mean change in sacral slope from standing to sitting was 22.1° ± 15.2° preoperatively and 19.5° ± 14.8° postoperatively. However, in 13 patients, the difference in pelvic motion from the standing to seated position, from preoperatively to postoperatively, was >5° and in 10 patients, this difference was >10°.The change in standing to sitting sacral slope was significantly less in patients with a lumbar fusion (9.8° ± 8.2°) and history of prosthetic dislocation (12.5° ± 4.7°) vs group A (P < .001 and P = .008).Conclusion
Implantation of a THA can increase or decrease sagittal plane pelvic motion from the standing to seated position with a high degree of variability. Thus, the ability to predict ideal component positioning from preoperative images may be challenging. 相似文献8.
Michael C. Worlicek Michael L. Wörner Benjamin S. Craiovan Florian Zeman Joachim Grifka Tobias F. Renkawitz Markus Weber 《The Journal of arthroplasty》2017,32(9):2892-2897
Background
Assessing femoral version in orthopedic surgery is important for preoperative planning of total hip arthroplasty, especially for recognizing excessive anteversion or retroversion. The present study addressed the following: (1) Is the position of the lesser trochanter correlated to the femoral neck axis? (2) If so, may femoral version be assessed by means of plain pelvic radiographs?Methods
Three-dimensional computed tomography scans of 60 patients undergoing minimally invasive cement-free total hip arthroplasty were retrospectively analyzed, particularly with regard to the relation between the femoral neck axis and the lesser trochanter, the femoral version, and the size of the projected lesser trochanter in different rotational positions. Based on linear regression, a biomathematical formula was developed to assess femoral anteversion on plain radiographs depending on the visible part of the lesser trochanter.Results
The mean difference between the location of the lesser trochanter axis and the femoral neck axis was 43.3° ± 6.2°. Eighty-seven percent of patients (52 of 60) had a deviation of <10° from the mean value of 43.3°. By virtual rotation of the femur in steps of 10°, the visible part of the lesser trochanter linearly increased with anteversion of the femur: femoral version = (lesser trochanter size ? 5.57) × 4.17. There was a high correlation between the visible part of the lesser trochanter and femoral version (R2 = 0.75; P < .001). The lesser trochanter was no longer visible with femoral retroversion in each of the 60 data sets.Conclusion
The projected size of the lesser trochanter as available on plain pelvic AP radiographs correlates with native femoral anteversion. 相似文献9.
Edward M. DelSole Jonathan M. Vigdorchik Ran Schwarzkopf Thomas J. Errico Aaron J. Buckland 《The Journal of arthroplasty》2017,32(6):1910-1917
Background
Changes in spinal alignment and pelvic tilt alter acetabular orientation in predictable ways, which may have implications on stability of total hip arthroplasty (THA). Patients with sagittal spinal deformity represent a subset of patients who may be at particularly high risk of THA instability because of postural compensation for abnormal spinal alignment.Methods
Using standing stereoradiography, we evaluated the spinopelvic parameters, acetabular cup anteversion, and inclination of 139 THAs in 107 patients with sagittal spinal deformity. Standing images were compared with supine pelvic radiographs to evaluate dynamic changes in acetabular cup position. Dislocation and revision rates were procured through retrospective chart review. The spinal parameters and acetabular cup positions among dislocators were compared with those who did not dislocate.Results
The rate of THA dislocation in this cohort was 8.0%, with a revision rate of 5.8% for instability. Patients who sustained dislocations had significantly higher spinopelvic tilt, T1-pelvic angle, and mismatch of lumbar lordosis and pelvic incidence. Among all patients, 78% had safe anteversion while supine, which decreased significantly to 58% when standing due to increases in spinopelvic tilt. Among dislocating THA, 80% had safe anteversion, 80% had safe inclination, and 60% had both parameters within the safe zone.Conclusion
In this cohort, patients with THA and concomitant spinal deformity have a particularly high rate of THA instability despite having an acetabular cup position traditionally thought of as within acceptable alignment. This dislocation risk may be driven by the degree of spinal deformity and by spinopelvic compensation. Surgeons should anticipate potential instability after hip arthroplasty and adjust their surgical plan accordingly. 相似文献10.
Raul G. Gosthe Juan C. Suarez Colin A. McNamara Cecilia Calvo Preetesh D. Patel 《The Journal of arthroplasty》2017,32(10):3052-3055
Background
Obesity has been described as an independent risk factor for acetabular component malpositioning. The purpose of this study was to determine if this could be overcome by use of fluoroscopic navigation in total hip arthroplasty (THA).Methods
The first, postoperative, standing, anteroposterior pelvis radiographs from 1599 consecutive patients who underwent fluoroscopic-guided THAs via anterior approach during a six-year period were obtained. We retrospectively reviewed this prospectively collected data. Inclination and anteversion were measured as described by Barrack et al. Intraoperative target ranges for inclination and anteversion angles were 30°-50° and 5°-25°. Patients were divided into 3 cohorts by body mass index, nonobese (<30 kg/m2) obese (between 30 and 40 kg/m2) and morbidly obese (>40 kg/m2), looking for significant differences in acetabular component positioning.Results
Of the 1599 patients, 1065 were nonobese, 506 obese, and 28 morbidly obese. Overall, average inclination was 37.7° and anteversion was 16.3°. Regarding inclination, 95.0% of cups were positioned in the safe zone, 95.7% for anteversion, and 91.2% for both inclination and anteversion. Analysis of each cohort individually revealed an average inclination of 37.5° in the nonobese, 37.9° in the obese, and 39.9° in the morbidly obese patients. For anteversion, each group's averages were 16.1°, 16.5°, and 16.0°, respectively. There was no significant relationship between a patient's body mass index and cup position for inclination (P = .867), anteversion (P = .673), or both inclination and anteversion (P = .624).Conclusion
Fluoroscopy is a useful tool for achieving a targeted acetabular component orientation in direct anterior THA, irrespective of patient BMI. 相似文献11.
Kentaro Iwakiri Akio Kobayashi Yoichi Ohta Kunio Takaoka 《The Journal of arthroplasty》2017,32(5):1520-1524
Background
Total hip arthroplasty in the lateral position involves particularly large variance in the sagittal tilt of pelvis fixation, which affects the imprecision of the cup anteversion leading to poor outcomes. We have added an additional compression pad to an existing device, also to be used in the lateral position, but theoretically enabling fixation on the anatomical pelvic plane (APP) serving as the reference plane. The present study aims to evaluate the usefulness of this device in comparison with the conventional device.Methods
We have studied 141 patients who underwent total hip arthroplasty at our hospital. Two frontal plain x-rays of the pelvis were obtained preoperatively for each patient after pelvis fixation; one with the conventional lateral fixation device and the other with an APP lateral fixation device. The sagittal tilt of the pelvis in each position was measured with 3D templating software, and variance in the sagittal tilt was compared between the 2 devices.Results
The mean bias in sagittal tilt relative to the functional pelvic plane (FPP) in the conventional device was ?5.0° ± 4.8° (minus mean backward tilt) and was within 5° relative to the functional pelvic plane in 43%. The mean bias in the sagittal tilt relative to the APP in the APP lateral position device was 1.7° ± 3.1° (forward tilt) and was within 5° relative to the APP in 89%. The APP lateral device significantly reduced the variance in the sagittal tilt.Conclusion
This device holds promise as a means of reducing the sagittal tilt in a simple, minimally invasive, and highly cost-effective manner. 相似文献12.
Naofumi Taniguchi Tetsuya Jinno Daisuke Koga Tetsuo Hagino Atsushi Okawa Hirotaka Haro 《The Journal of arthroplasty》2017,32(5):1547-1552
Background
Appropriate stem anteversion is important for achieving stability of the prosthetic joint in total hip arthroplasty. Anteversion of a cementless femoral stem is affected by the femoral canal morphology and varies according to stem geometry. We investigated the difference and variation of the increase in anteversion between 2 types of cementless stems, and the correlation between each stem and the preoperative femoral anteversion.Methods
We retrospectively compared 2 groups of hips that underwent total hip arthroplasty using a metaphyseal filling stem (78 hips) or a tapered wedge stem (83 hips). All the patients had osteoarthritis due to hip dysplasia. Computed tomography was used to measure preoperative femoral anteversion at 5 levels and postoperative stem anteversion.Results
The increase in anteversion of the tapered wedge stem group (22.7° ± 11.6°) was more than that of the metaphyseal filling stem group (17.2° ± 8.3°; P = .0007). The variation of the increase in the tapered wedge stem group was significantly larger than that in the metaphyseal filling stem group (P = .0016). The metaphyseal filling stem group was more highly and positively correlated with femoral anteversion than the tapered wedge stem group.Conclusion
Femoral anteversion affects stem anteversion differently according to stem geometry. The tapered wedge stems had greater variation of the increase in anteversion than did the metaphyseal filling stems. Based on the results of this study, it is difficult to preoperatively estimate the increase in stem anteversion for tapered wedge stems. 相似文献13.
Adam R. Boissonneault Takafumi Hiranaka James R. Roberson Thomas L. Bradbury 《The Journal of arthroplasty》2017,32(3):1018-1023
Background
Although preoperative templating in total hip arthroplasty is helpful to ensure appropriate component position, there is no single-view radiographic method to determine femoral anteversion (FA) preoperatively. The aim of the present study was to validate the use of radiographic measurement of FA using a modified Budin view.Methods
This prospective study reports on 105 limbs from 65 patients. Computed tomography (CT) scans and radiographs were obtained to measure native FA. Radiographs were obtained using the modified Budin protocol with 90° flexion at the knee and 90° flexion and 30° abduction at the hip. Pearson correlation analyses, paired-samples t-test, and Bland-Altman plots were performed to assess correlation and agreement between methods. Data were grouped into subsets based on CT-derived FA in 5° intervals. Groups included all limbs, FA < 35°, FA < 30°, and FA < 25°.Results
For all limbs, Bland-Altman analysis revealed a fixed bias (mean bias, ?0.8°; 95% confidence interval, ?1.4° to ?0.2°) and showed that radiographic methods underestimated FA. Subset analyses were performed and revealed excellent correlation between CT and radiographic measurements for all subgroups (r = 0.97, P < .001). Paired-samples t-tests revealed no significant difference between methodologies for any of the subgroups. Radiographic and CT methods showed excellent agreement, and the bias between methods was within 0.5° for all subgroups. There was no fixed bias and thus no systematic difference in methods within any of the subgroup analyses.Conclusion
Radiographic measurement of FA using a modified Budin view is a valid and reliable technique. 相似文献14.
Min Chen Zhengliang Luo Xiaofeng Ji Peng Cheng Guolin Tang Xifu Shang 《The Journal of arthroplasty》2017,32(1):131-138
Background
The direct anterior approach (DAA) for total hip arthroplasty (THA) is typically performed in the supine position using a specially designed operating room table, which makes this approach more accessible to orthopedic surgeons. We attempted to perform this procedure in the lateral decubitus position on an ordinary operation table to avoid dependence on a special operating room table. There is an obvious absence of literature regarding this subject.Methods
A total of 248 patients (295 hips) were recruited for primary THAs from July 1, 2014 to December 31, 2014. In total, 126 hips (42.7%) underwent THAs using the DAA in the lateral decubitus position. The technical feasibility and early results were evaluated.Results
The orientation of the acetabular component was 16.5° ± 4.9° anteversion and 43.3° ± 3.5° abduction. Intraoperative proximal femoral fracture occurred in one hip. The superficial wound complications occurred in 2 hips and the hematoma in one hip while in hospital. The lateral femoral cutaneous nerve injury was noted in 43 hips. The early dislocation occurred in 2 hips. Heterotopic ossification was Brooker class I in 5 hips and class II in 1 hip. No aseptic loosening, postoperative periprosthetic fracture, and deep infection occurred in our series.Conclusion
The DAA for THA in the lateral decubitus position may be a valuable alternative if the DAA in the supine position is difficult to implement owing to absence of a special operating room table. This technique also seems to provide satisfactory clinical and radiographic outcomes with an acceptable complication in our early follow-up. 相似文献15.
Kentaro Iwakiri Akio Kobayashi Yoichi Ohta Yukihide Minoda Kunio Takaoka Hiroaki Nakamura 《The Journal of arthroplasty》2017,32(12):3659-3664
Background
The acetabular component orientation in total hip arthroplasty (THA) is of critical importance to the good clinical results. However, traditional widely used cup alignment guides for cup placement are reported to be relatively unreliable. The present study aims at comparing a novel cup alignment guide, which can be attached to our anatomical pelvic plane (APP) pelvic lateral positioner for reducing discrepancies in sagittal pelvic tilt and indicate a targeted cup angle based on the APP, with a conventional cup alignment guide.Methods
The subjects were 136 hips of 136 patients who underwent unilateral THA using the APP positioner. The procedure was performed with the conventional cup alignment guide (conventional group; 60 hips) and with the novel cup navigator (mechanical navigator group; 76 hips). Postoperative cup angles and discrepancies of postoperative cup angles (inclination and anteversion angles) from the targeted angles were compared between the 2 groups to evaluate the usefulness of these navigators.Results
The mean cup angles in the conventional group were 39.0° ± 5.3° for the inclination angle and 21.7° ± 6.4° for the anteversion angle, whereas those in the mechanical navigator group were 40.6° ± 3.2° and 18.3° ± 4.6°, respectively (P = .018, P < .0001). The discrepancies from the targeted angles were 3.5° ± 3.1° for the inclination angle and 4.6° ± 3.4° for the anteversion angle in the conventional group and 2.3° ± 2.3° and 3.2° ± 2.7°, respectively, in the mechanical navigator group (P = .020, P = .012).Conclusion
The mechanical cup navigator easily attachable to the APP positioner is a tool that can improve the accuracy of cup placement in a simple, economical, and noninvasive manner in THA via the lateral position. 相似文献16.
Thomas F. McCarthy Jim Nevelos Randa K. Elmallah Morad Chughtai Anton Khlopas Vincent Alipit Timothy C. Wagner Michael A. Mont 《The Journal of arthroplasty》2017,32(11):3544-3549
Background
About 50%-70% of dislocators have cups placed within so-called “safe zones.” It has been postulated that factors such as femoral head size and pelvic tilt, obliquity, or rotation may influence postoperative stability. Therefore, we assessed varying degrees of pelvic tilt and head sizes on the range of motion (ROM) to impingement.Methods
A hip simulator was used to import models of 10 subjects who performed object pickup, squatting, and low-chair rising. Parameters were set for pelvic tilt, stem version, and the specific motions as defined by the subjects. Femur-to-pelvis relative motions were determined for abduction/adduction, internal/external rotation, and flexion/extension. Varying tilt angles were tested. Thirty-two millimeter and 36-mm head with a standard cup and 42-mm dual mobility cup were tested. Cup orientations for abduction and anteversion combinations were chosen, and computations of minimum clearances or impingement between components were made.Results
The ROM to impingement varied with the different pelvic tilts and femoral head sizes and with the different motions. The larger the head size, the larger the impingement-free ROM. Negative 10° of pelvic tilt led to the largest impingement-free zone, whereas 10° of forward tilt was associated with fewer impingement-free cup anteversion and abduction angle combinations. Variations in pelvic tilt had the greatest influence on object pickup and affected the impingement-free “safe zone.”Conclusion
Targets for impingement-free motion may be smaller when considering varying pelvic tilts and femoral head sizes, particularly for certain activities, such as object pickup. These findings may indicate the need for more individualized patient planning. 相似文献17.
Tim A.E.J. Boymans Hidde D. Veldman Philip C. Noble Ide C. Heyligers Bernd Grimm 《The Journal of arthroplasty》2017,32(2):581-586
Background
Accurate reconstruction of hip joint biomechanics is the key stone in total hip arthroplasty. Although proximal femur morphology is known to vary with both age and gender, few studies investigated this in the very elderly (ie, ≥80 years). The purpose of this study was to compare basic morphological parameters describing the position of the femoral head between very elderly and middle-aged subjects.Methods
Computed tomographic scans of the femur of 90 very elderly (mean 84 years, range 80-105 years) and 58 middle-aged subjects (mean 52 years, range 20-79 years) were made. After 3-dimensional reconstruction, the neck-shaft angle, femoral neck anteversion angle, femoral head height, femoral neck length, and mediolateral offset (ML-offset) were determined.Results
The neck-shaft angle was on average 3.6° less in elderly males (125.9° ± 5.0°) than in middle-aged males (129.5° ± 5.1°) (P < .001). The femoral neck anteversion angle was not significantly different between both age and gender groups. The femoral head height was ?12.3 mm in elderly females compared to ?10.5 mm (Δ 17%) in elderly males (P = .284) and even ?8.0 mm (Δ 54%) in middle-aged males. The ML-offset was 10% (4.1 mm) larger in elderly compared to middle-aged males (P < .001).Conclusion
These findings suggest that the femoral neck and head shift in a relative varus position during aging. Femoral prostheses with increased ML-offset and a lower caput-collum-diaphyseal angle are needed to accommodate the morphology of the femur in the very elderly. Care must be taken not to lengthen the operated leg, particularly in very elderly females. 相似文献18.
Jonathan G. Haw Andrew K. Battenberg Der-Chen T. Huang Thomas P. Schmalzried 《The Journal of arthroplasty》2017,32(4):1381-1386
Background
Cross-linked polyethylene (XLPE) has demonstrated significantly reduced wear and osteolysis into the second decade for total hip arthroplasty. There is a relative paucity of data with ≥36-mm bearings. Issues include potential effects of reduced liner thickness and component position on wear, osteolysis, and mechanical failure of the bearing.Methods
Radiographs of 48 primary total hip arthroplasties with ≥36-mm modular XLPE bearings were analyzed at a minimum 5 years postoperative on serial radiographs using a validated, edge-detection-based algorithm. Subgroups were examined to assess the effect of bearing diameter, liner thickness, acetabular abduction angle, and acetabular anteversion on XLPE wear.Results
There was no significant difference in volumetric wear when subgroups were stratified by component factors: liner thickness (<6.5 mm vs ≥6.5 mm) 40.69 mm3/y vs 24.47 mm3/y, respectively (P = .315); acetabular component abduction angle (<45° vs ≥45°): 38.68 mm3/y vs 27.8 mm3/y, respectively (P = .522); acetabular anteversion (<20° vs ≥20°): 41.32 mm3/y vs 31.79 mm3/y, respectively (P = .521). There were no dislocations, mechanical failures, or revisions. There were 7 hips with volumetric wear rates ≥80 mm3/y; 1 had possible osteolysis.Conclusion
Larger-diameter XLPE wear was not measurably affected by liner thickness, acetabular abduction angle, or acetabular anteversion. However, there is a trend for increasing volumetric wear with increasing bearing size. Wear outliers do occur, and continued follow-up of larger-diameter XLPE bearings is warranted. 相似文献19.
Jun-Dong Chang In-Sung Kim Sharad Prabhakar Sameer A. Mansukhani Sang-Soo Lee Je-Hyun Yoo 《The Journal of arthroplasty》2017,32(5):1576-1580
Background
The purpose of the study was to evaluate the implant positions and clinical results of revision total hip arthroplasty (THA) using an imageless navigation with the concept of combined anteversion.Methods
A total of 40 cementless revision THAs (24 men and 16 women) using an imageless navigation with the concept of combined anteversion were retrospectively evaluated. The concept of combined anteversion was applied in cup positioning based on Widmer's equation (cup anteversion + 0.7 × stem anteversion). The mean follow-up period was 80.7 months. Postoperatively, the inclination of the cup was evaluated on standard anteroposterior view of the radiograph, and the anteversion of the cup and femoral stem was evaluated using computed tomography scan. A cup inclination of 40° ± 10° and combined anteversion of the cup and femoral stem of 37° ± 10° based on Widmer's equation were regarded as the “safe zone.”Results
The average anteversion of the revised femoral stems was 15.3° ± 2.9° (range, 9.5°-21.5°), whereas that of the remained femoral stems was 17.4° ± 9.7° (range, 4.2°-29.8°). The inclination, anteversion of the cup, and combined anteversion after revision THA were 42.3° ± 3.1° (range, 32.1°-48.2°), 25.0° ± 2.9° (range, 16.9°-29.5°), and 36.1° ± 3.4° (range, 27.2°-42.9°), respectively. Therefore, the position of the implants, relative to the safe zone, showed no outliers after the revision surgery. Neither dislocation nor osteolysis was observed after the surgery.Conclusion
Favorable results of this study indicate that imageless navigation helps the surgeon in placing the components of revision THA in the safe zone. This study also shows that when this safe zone is consistently obtained, then no postoperative dislocations were observed in these patients over the 6-year follow-up period. 相似文献20.
Masanori Fujii Tetsuro Nakamura Toshihiko Hara Yasuharu Nakashima 《Journal of orthopaedic science》2017,22(6):1089-1095