Aims. This study aims to: determine the difference in pelvic
Aims. The direct anterior approach (DAA) for total hip arthroplasty (THA) has potential advantages over other approaches and is most commonly performed with the patient in the supine
Aims. The aim of this study was to examine the implant accuracy of custom-made partial pelvis replacements (PPRs) in revision total hip arthroplasty (rTHA). Custom-made implants offer an option to achieve a reconstruction in cases with severe acetabular bone loss. By analyzing implant deviation in CT and radiograph imaging and correlating early clinical complications, we aimed to optimize the usage of custom-made implants. Methods. A consecutive series of 45 (2014 to 2019) PPRs for Paprosky III defects at rTHA were analyzed comparing the preoperative planning CT scans used to manufacture the implants with postoperative CT scans and radiographs. The anteversion (AV), inclination (IC), deviation from the preoperatively planned implant
Aims. The primary aim of this study was to define and quantify three
new measurements to indicate the
A variety of radiological methods of measuring
version of the acetabular component after total hip replacement (THR)
have been described. The aim of this study was to evaluate the reliability
and validity of six methods (those of Lewinnek; Widmer; Hassan et
al; Ackland, Bourne and Uhthoff; Liaw et al; and Woo and Morrey)
that are currently in use. In 36 consecutive patients who underwent
THR, version of the acetabular component was measured by three independent
examiners on plain radiographs using these six methods and compared
with measurements using CT scans. The intra- and interobserver reliabilities
of each measurement were estimated. All measurements on both radiographs
and CT scans had excellent intra- and interobserver reliability
and the results from each of the six methods correlated well with
the CT measurements. However, measurements made using the methods
of Widmer and of Ackland, Bourne and Uhthoff were significantly
different from the CT measurements (both p <
0.001), whereas
measurements made using the remaining four methods were similar
to the CT measurements. With regard to reliability and convergent
validity, we recommend the use of the methods described by Lewinnek,
Hassan et al, Liaw et al and Woo and Morrey for measurement of version
of the acetabular component.
Aims. Posterior tilt of the pelvis with sitting provides biological
acetabular opening. Our goal was to study the post-operative interaction
of skeletal mobility and sagittal acetabular component
Aims. The aims of this study were to measure sagittal standing and sitting lumbar-pelvic-femoral alignment in patients before and following total hip arthroplasty (THA), and to consider what preoperative factors may influence a change in postoperative pelvic
The aim of this cadaver study was to identify
the change in
Aims. The aim of this study was to evaluate the accuracy of implant placement when using robotic assistance during total hip arthroplasty (THA). Patients and Methods. A total of 20 patients underwent a planned THA using preoperative CT scans and robotic-assisted software. There were nine men and 11 women (n = 20 hips) with a mean age of 60.8 years (. sd. 6.0). Pelvic and femoral bone models were constructed by segmenting both preoperative and postoperative CT scan images. The preoperative anatomical landmarks using the robotic-assisted system were matched to the postoperative 3D reconstructions of the pelvis. Acetabular and femoral component
Aims. The hypothesis of this study was that thigh circumference, distinct from body mass index (BMI), may be associated with the
The orientation of the acetabular component is
influenced not only by the orientation at which the surgeon implants
the component, but also the orientation of the pelvis at the time
of implantation. Hence, the orientation of the pelvis at set-up
and its movement during the operation, are important. During 67
hip replacements, using a validated photogrammetric technique, we
measured how three surgeons orientated the patient’s pelvis, how
much the pelvis moved during surgery, and what effect these had
on the final orientation of the acetabular component. Pelvic orientation
at set-up, varied widely (mean (± 2, standard deviation (. sd. ))):
tilt 8° (2. sd . ±32), obliquity –4° (2. sd . ±12), rotation
–8° (2. sd . ±14). Significant differences in pelvic positioning
were detected between surgeons (p <
0.001). The mean angular
movement of the pelvis between set-up and component implantation
was 9° (. sd. 6). Factors influencing pelvic movement included
surgeon, approach (posterior >
lateral), procedure (hip resurfacing
>
total hip replacement) and type of support (p <
0.001). Although,
on average, surgeons achieved their desired acetabular component
orientation, there was considerable variability (2. sd. ±16)
in component orientation. We conclude that inconsistency in positioning
the patient at set-up and movement of the pelvis during the operation account
for much of the variation in acetabular component orientation. Improved
methods of
We evaluated the accuracy with which a custom-made
acetabular component could be
We investigated factors that were thought to be associated with an increased incidence of squeaking of ceramic-on-ceramic total hip replacements. Between June 1997 and December 2008 the three senior authors implanted 2406 primary total hip replacements with a ceramic-on-ceramic bearing surface. The mean follow-up was 10.6 years. The diagnosis was primary osteoarthritis in each case, and no patient had undergone previous surgery to the hip. We identified 74 squeaking hips (73 patients) giving an incidence of 3.1% at a mean follow-up of 9.5 years (4.1 to 13.3). Taller, heavier and younger patients were significantly more likely to have hips that squeaked. Squeaking hips had a significantly higher range of post-operative internal (p = 0.001) and external rotation (p = 0.003) compared with silent hips. Patients with squeaking hips had significantly higher activity levels (p = 0.009). A squeaking hip was not associated with a significant difference in patient satisfaction (p = 0.24) or Harris hip score (p = 0.34). Four implant
There are several techniques for the accurate measurement of the migration of components after arthroplasty some of which require the operative placement of tantalum balls. We have reviewed the
We have reviewed 54 patients who had undergone 61 total hip replacements using bulk femoral autografts to augment a congenitally dysplastic acetabulum. There were 52 women and two men with a mean age of 42.4 years (29 to 76) at the time of the index operation. A variety of different prostheses was used: 28 (45.9%) were cemented and 33 (54.1%) uncemented. The graft technique remained unchanged throughout the series. Follow-up was at a mean of 8.3 years (3 to 20). The Hospital for Special Surgery hip score improved from a mean of 10.7 (4 to 18) pre-operatively to a mean of 35 (28 to 38) at follow-up. The
Aims. The aim of this study is to evaluate whether acetabular retroversion (AR) represents a structural anatomical abnormality of the pelvis or is a functional phenomenon of pelvic
Aims. Achieving accurate implant
Aims. This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different
Aims. Refobacin Bone Cement R and Palacos R + G bone cement were introduced to replace the original cement Refobacin Palacos R in 2005. Both cements were assumed to behave in a biomechanically similar fashion to the original cement. The primary aim of this study was to compare the migration of a polished triple-tapered femoral stem fixed with either Refobacin Bone Cement R or Palacos R + G bone cement. Repeated radiostereometric analysis was used to measure migration of the femoral head centre. The secondary aims were evaluation of cement mantle, stem
Aims. Acetabular retroversion is a recognized cause of hip impingement and can be influenced by pelvic tilt (PT), which changes in different functional