Aims. Spinopelvic mobility plays an important role in functional acetabular component position following total hip arthroplasty (THA). The primary aim of this study was to determine if spinopelvic
Aims. This study of patients with osteoarthritis (OA) of the hip aimed to: 1) characterize the contribution of the hip, spinopelvic complex, and lumbar spine when moving from the standing to the sitting position; 2) assess whether abnormal spinopelvic mobility is associated with worse symptoms; and 3) identify whether spinopelvic mobility can be predicted from static anatomical radiological parameters. Patients and Methods. A total of 122 patients with end-stage OA of the hip awaiting total hip arthroplasty (THA) were prospectively studied. Patient-reported outcome measures (PROMs; Oxford Hip Score, Oswestry Disability Index, and Veterans RAND 12-Item Health Survey Score) and clinical data were collected. Sagittal spinopelvic mobility was calculated as the change from the standing to sitting position using the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic-femoral angle (PFA), and acetabular anteinclination (AI) from lateral radiographs. The interaction of the different parameters was assessed. PROMs were compared between patients with normal spinopelvic mobility (10° ≤ ∆PT ≤ 30°) or abnormal spinopelvic mobility (stiff: ∆PT < ± 10°; hypermobile: ∆PT > ± 30°). Multiple regression and receiver operating characteristic (ROC) curve analyses were used to test for possible predictors of spinopelvic mobility. Results. Standing to sitting, the hip flexed by a mean of 57° (. sd. 17°), the pelvis tilted backwards by a mean of 20° (. sd. 12°), and the lumbar spine flexed by a mean of 20° (. sd. 14°); strong correlations were detected. There was no difference in PROMs between patients in the different spinopelvic mobility groups. Maximum hip flexion, standing PT, and standing AI were independent predictors of spinopelvic mobility (R. 2. = 0.42). The combined thresholds for standing was PT ≥ 13° and hip flexion ≥ 88° in the clinical examination, and had 90% sensitivity and 63% specificity of predicting spinopelvic stiffness, while SS ≥ 42° had 84% sensitivity and 67% specificity of predicting spinopelvic
Pelvic incidence (PI) is a position-independent spinopelvic parameter traditionally used by spinal surgeons to determine spinal alignment. Its relevance to the arthroplasty surgeon in assessing patient risk for total hip arthroplasty (THA) instability preoperatively is unclear. This study was undertaken to investigate the significance of PI relative to other spinopelvic parameter risk factors for instability to help guide its clinical application. Retrospective analysis was performed of a multicentre THA database of 9,414 patients with preoperative imaging (dynamic spinopelvic radiographs and pelvic CT scans). Several spinopelvic parameter measurements were made by engineers using advanced software including sacral slope (SS), standing anterior pelvic plane tilt (APPT), spinopelvic tilt (SPT), lumbar lordosis (LL), and PI. Lumbar flexion (LF) was determined by change in LL between standing and flexed-seated lateral radiographs. Abnormal pelvic mobility was defined as ∆SPT ≥ 20° between standing and flexed-forward positions. Sagittal spinal deformity (SSD) was defined as PI-LL mismatch > 10°.Aims
Methods
Use of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased in recent years due to proposed benefits, including a lower risk of dislocation and improved early functional recovery. This study investigates the dislocation rate in a non-selective, consecutive cohort undergoing THA via the DAA without any exclusion or bias in patient selection based on habitus, deformity, age, sex, or fixation method. We retrospectively reviewed all patients undergoing THA via the DAA between 2011 and 2017 at our institution. Primary outcome was dislocation at minimum two-year follow-up. Patients were stratified by demographic details and risk factors for dislocation, and an in-depth analysis of dislocations was performed.Aims
Methods
Periacetabular osteotomy is an effective way of treating symptomatic
hip dysplasia. We describe a new minimally invasive technique using
a modification of the Smith-Peterson approach. We performed a prospective, longitudinal cohort study to assess
for any compromise in acetabular correction when using this approach,
and to see if the procedure would have a higher complication rate
than that quoted in the literature for other approaches. We also
assessed for any improvement in functional outcome. From 168 consecutive patients (189 hips) who underwent acetabular
correction between March 2010 and March 2013 we excluded those who
had undergone previous pelvic surgery for DDH and those being treated
for acetabular retroversion. The remaining 151 patients (15 men,
136 women) (166 hips) had a mean age of 32 years (15 to 56) and the
mean duration of follow-up was 2.8 years (1.2 to 4.5). In all 90%
of cases were Tönnis grade 0 or 1. Functional outcomes were assessed
using the Non Arthritic Hip Score (NAHS), University of California,
Los Angeles (UCLA) and Tegner activity scores.Aims
Patients and Methods
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 position. A total of 161 patients were considered for inclusion. Patients had a mean age of the remaining 61 years (Aims
Patients and Methods
The hip’s capsular ligaments passively restrain extreme range of movement (ROM) by wrapping around the native femoral head/neck. We determined the effect of hip resurfacing arthroplasty (HRA), dual-mobility total hip arthroplasty (DM-THA), conventional THA, and surgical approach on ligament function. Eight paired cadaveric hip joints were skeletonized but retained the hip capsule. Capsular ROM restraint during controlled internal rotation (IR) and external rotation (ER) was measured before and after HRA, DM-THA, and conventional THA, with a posterior (right hips) and anterior capsulotomy (left hips).Aims
Materials and Methods
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 position. This was a radiographic study of 160 hips (151 patients) who
prospectively had lateral spinopelvic hip radiographs for skeletal
and implant measurements. Intra-operative acetabular component position
was determined according to the pre-operative spinal mobility. Sagittal
implant measurements of ante-inclination and sacral acetabular angle were
used as surrogate measurements for the risk of impingement, and
intra-operative acetabular component angles were compared with these.Aims
Materials and Methods
Down’s syndrome is associated with a number of
musculoskeletal abnormalities, some of which predispose patients
to early symptomatic arthritis of the hip. The purpose of the present
study was to review the general and hip-specific factors potentially
compromising total hip replacement (THR) in patients with Down’s
syndrome, as well as to summarise both the surgical techniques that
may anticipate the potential adverse impact of these factors and
the clinical results reported to date. A search of the literature
was performed, and the findings further informed by the authors’
clinical experience, as well as that of the hip replacement in Down
Syndrome study group. The general factors identified include a high
incidence of ligamentous laxity, as well as associated muscle hypotonia
and gait abnormalities. Hip-specific factors include: a high incidence
of hip dysplasia, as well as a number of other acetabular, femoral
and combined femoroacetabular anatomical variations. Four studies
encompassing 42 hips, which reported the clinical outcomes of THR
in patients with Down’s syndrome, were identified. All patients
were successfully treated with standard acetabular and femoral components.
The use of supplementary acetabular screw fixation to enhance component
stability was frequently reported. The use of constrained liners
to treat intra-operative instability occurred in eight hips. Survival
rates of between 81% and 100% at a mean follow-up of 105 months
(6 to 292) are encouraging. Overall, while THR in patients with
Down’s syndrome does present some unique challenges, the overall
clinical results are good, providing these patients with reliable
pain relief and good function. Cite this article:
The reported prevalence of an asymptomatic slip
of the contralateral hip in patients operated on for unilateral slipped
capital femoral epiphysis (SCFE) is as high as 40%. Based on a population-based
cohort of 2072 healthy adolescents (58% women) we report on radiological
and clinical findings suggestive of a possible previous SCFE. Common
threshold values for Southwick’s lateral head–shaft angle (≥ 13°)
and Murray’s tilt index (≥ 1.35) were used. New reference intervals
for these measurements at skeletal maturity are also presented. At follow-up the mean age of the patients was 18.6 years (17.2
to 20.1). All answered two questionnaires, had a clinical examination
and two hip radiographs. There was an association between a high head–shaft angle and
clinical findings associated with SCFE, such as reduced internal
rotation and increased external rotation. Also, 6.6% of the cohort
had Southwick’s lateral head–shaft angle ≥ 13°, suggestive of a
possible slip. Murray’s tilt index ≥ 1.35 was demonstrated in 13.1%
of the cohort, predominantly in men, in whom this finding was associated
with other radiological findings such as pistol-grip deformity or
focal prominence of the femoral neck, but no clinical findings suggestive
of SCFE. This study indicates that 6.6% of young adults have radiological
findings consistent with a prior SCFE, which seems to be more common
than previously reported. Cite this article:
