In this in vitro study of the
hip joint we examined which soft tissues act as primary and secondary
passive rotational restraints when the hip joint is functionally
loaded. A total of nine cadaveric left hips were mounted in a testing
rig that allowed the application of forces, torques and rotations
in all six degrees of freedom. The hip was rotated throughout a
complete
Pelvic tilt (PT) can significantly change the functional orientation of the acetabular component and may differ markedly between patients undergoing total hip arthroplasty (THA). Patients with stiff spines who have little change in PT are considered at high risk for instability following THA. Femoral component position also contributes to the limits of impingement-free range of motion (ROM), but has been less studied. Little is known about the impact of combined anteversion on risk of impingement with changing pelvic position. We used a virtual hip ROM (vROM) tool to investigate whether there is an ideal functional combined anteversion for reduced risk of hip impingement. We collected PT information from functional lateral radiographs (standing and sitting) and a supine CT scan, which was then input into the vROM tool. We developed a novel vROM scoring system, considering both seated flexion and standing extension manoeuvres, to quantify whether hips had limited ROM and then correlated the vROM score to component position.Aims
Methods
Our retrospective analysis reports the outcome of patients operated for slipped capital femoral epiphysis using the modified Dunn procedure. Results, complications, and the need for revision surgery are compared with the recent literature. We retrospectively evaluated 17 patients (18 hips) who underwent the modified Dunn procedure for the treatment of slipped capital femoral epiphysis. Outcome measurement included standardized scores. Clinical assessment included ambulation, leg length discrepancy, and hip mobility. Radiographically, the quality of epiphyseal reduction was evaluated using the Southwick and Alpha-angles. Avascular necrosis, heterotopic ossifications, and osteoarthritis were documented at follow-up.Aims
Methods
The aim of this study was to assess the functional gain achieved following hip resurfacing arthroplasty (HRA). A total of 28 patients (23 male, five female; mean age, 56 years (25 to 73)) awaiting Birmingham HRA volunteered for this prospective gait study, with an age-matched control group of 26 healthy adults (16 male, ten female; mean age, 56 years (33 to 84)). The Oxford Hip Score (OHS) and gait analysis using an instrumented treadmill were used preoperatively and more than two years postoperatively to measure the functional change attributable to the intervention.Aims
Patients and Methods
Our primary aim was to describe migration of the Exeter stem with a 32 mm head on highly crosslinked polyethylene and whether this is influenced by age. Our secondary aims were to assess functional outcome, satisfaction, activity, and bone mineral density (BMD) according to age. A prospective cohort study was conducted. Patients were recruited into three age groups: less than 65 years (n = 65), 65 to 74 years (n = 68), and 75 years and older (n = 67). There were 200 patients enrolled in the study, of whom 115 were female and 85 were male, with a mean age of 69.9 years (sd 9.5, 42 to 92). They were assessed preoperatively, and at three, 12 and, 24 months postoperatively. Stem migration was assessed using Einzel-Bild-Röntgen-Analyse (EBRA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), Hip Disability and Osteoarthritis Outcome Score (HOOS), EuroQol-5 domains questionnaire (EQ-5D), short form-36 questionnaire (SF-36,) and patient satisfaction were used to assess outcome. The Lower Extremity Activity Scale (LEAS), Timed Up and Go (TUG) test, and activPAL monitor (energy expelled, time lying/standing/walking and step count) were used to assess activity. The BMD was assessed in Gruen and Charnley zones.Objectives
Patients and Methods
Modular dual mobility (DM) prostheses in which a cobalt-chromium liner is inserted into a titanium acetabular shell ( This was a prospective study of patients between 18 and 65 years of age, with a body mass index (BMI) < 35 kg/m2 and University of California at Los Angeles (UCLA) activity score > 6, who received a modular cobalt-chromium acetabular liner, highly crosslinked polyethylene mobile bearing, and cementless titanium femoral stem for their primary THA. Patients with a history of renal disease and metal hardware elsewhere in the body were excluded. A total of 43 patients (30 male, 13 female; mean age 52.6 years (Aims
Patients and Methods
The purpose of this study was to evaluate the existing literature from 2005 to 2016 reporting on the efficacy of surgical management of patients with femoroacetabular impingement (FAI) secondary to slipped capital femoral epiphysis (SCFE). The electronic databases MEDLINE, EMBASE, and PubMed were searched and screened in duplicate. Data such as patient demographics, surgical technique, surgical outcomes and complications were retrieved from eligible studies.Objectives
Methods
Alarm over the reported high failure rates for metal-on-metal (MoM) hip implants as well as their potential for locally aggressive Adverse Reactions to Metal Debris (ARMDs) has prompted government agencies, internationally, to recommend the monitoring of patients with MoM hip implants. Some have advised that a blood ion level >7 µg/L indicates potential for ARMDs. We report a systematic review and meta-analysis of the performance of metal ion testing for ARMDs. We searched MEDLINE and EMBASE to identify articles from which it was possible to reconstruct a 2 × 2 table. Two readers independently reviewed all articles and extracted data using explicit criteria. We computed a summary receiver operating curve using a Bayesian random-effects hierarchical model.Objectives
Methods
The purpose of this study was to compare the thickness of the hip capsule in patients with surgical hip disease, either with cam-femoroacetabular impingement (FAI) or non-FAI hip pathology, with that of asymptomatic control hips. A total of 56 hips in 55 patients underwent a 3Tesla MRI of the hip. These included 40 patients with 41 hips with arthroscopically proven hip disease (16 with cam-FAI; nine men, seven women; mean age 39 years, 22 to 58) and 25 with non-FAI chondrolabral pathology (four men, 21 women; mean age 40 years, 18 to 63) as well as 15 asymptomatic volunteers, whose hips served as controls (ten men, five women; mean age 62 years, 33 to 77). The maximal capsule thickness was measured anteriorly and superiorly, and compared within and between the three groups with a gender subanalysis using student’s Objectives
Methods
Femoroacetabular impingement (FAI) causes pain
and chondrolabral damage via mechanical overload during movement
of the hip. It is caused by many different types of pathoanatomy,
including the cam ‘bump’, decreased head–neck offset, acetabular
retroversion, global acetabular overcoverage, prominent anterior–inferior
iliac spine, slipped capital femoral epiphysis, and the sequelae
of childhood Perthes’ disease. Both evolutionary and developmental factors may cause FAI. Prevalence
studies show that anatomic variations that cause FAI are common
in the asymptomatic population. Young athletes may be predisposed
to FAI because of the stress on the physis during development. Other
factors, including the soft tissues, may also influence symptoms and
chondrolabral damage. FAI and the resultant chondrolabral pathology are often treated
arthroscopically. Although the results are favourable, morphologies
can be complex, patient expectations are high and the surgery is
challenging. The long-term outcomes of hip arthroscopy are still
forthcoming and it is unknown if treatment of FAI will prevent arthrosis.
The purpose of this study was to investigate whether the femoral
head–neck contour, characterised by the alpha angle, varies with
the stage of physeal maturation using MRI evaluation of an asymptomatic
paediatric population. Paediatric volunteers with asymptomatic hips were recruited to
undergo MRI of both hips. Femoral head physes were graded from 1
(completely open) to 6 (completely fused). The femoral head–neck
contour was evaluated using the alpha angle, measured at the 3:00
(anterior) and 1:30 (anterosuperior) positions and correlated with
physeal grade, with gender sub-analysis performed.Objectives
Methods
Metal-on-metal hip resurfacing (MOMHR) is available as an alternative
option for younger, more active patients. There are failure modes
that are unique to MOMHR, which include loosening of the femoral
head and fractures of the femoral neck. Previous studies have speculated
that changes in the vascularity of the femoral head may contribute
to these failure modes. This study compares the survivorship between
the standard posterior approach (SPA) and modified posterior approach
(MPA) in MOMHR. A retrospective clinical outcomes study was performed examining
351 hips (279 male, 72 female) replaced with Birmingham Hip Resurfacing
(BHR, Smith and Nephew, Memphis, Tennessee) in 313 patients with
a pre-operative diagnosis of osteoarthritis. The mean follow-up
period for the SPA group was 2.8 years (0.1 to 6.1) and for the
MPA, 2.2 years (0.03 to 5.2); this difference in follow-up period
was statistically significant (p <
0.01). Survival analysis was
completed using the Kaplan–Meier method. Objectives
Methods
This study compared the primary stability of two commercially
available acetabular components from the same manufacturer, which
differ only in geometry; a hemispherical and a peripherally enhanced
design (peripheral self-locking (PSL)). The objective was to determine
whether altered geometry resulted in better primary stability. Acetabular components were seated with 0.8 mm to 2 mm interference
fits in reamed polyethylene bone substrate of two different densities
(0.22 g/cm3 and 0.45 g/cm3). The primary stability
of each component design was investigated by measuring the peak
failure load during uniaxial pull-out and tangential lever-out tests.Objective
Methods
An ongoing prospective study to investigate failing metal-on-metal
hip prostheses was commenced at our centre in 2008. We report on
the results of the analysis of the first consecutive 126 failed
mated total hip prostheses from a single manufacturer. Analysis was carried out using highly accurate coordinate measuring
to calculate volumetric and linear rates of the articular bearing
surfaces and also the surfaces of the taper junctions. The relationship
between taper wear rates and a number of variables, including bearing
diameter and orientation of the acetabular component, was investigated.Objectives
Methods
Over recent years hip arthroscopic surgery has
evolved into one of the most rapidly expanding fields in orthopaedic surgery.
Complications are largely transient and incidences between 0.5%
and 6.4% have been reported. However, major complications can and
do occur. This article analyses the reported complications and makes recommendations
based on the literature review and personal experience on how to
minimise them.
