Aims. Acetabular edge-loading was a cause of increased wear rates in metal-on-metal hip arthroplasties, ultimately contributing to their failure. Although such wear patterns have been regularly reported in retrieval analyses, this study aimed to determine their in vivo location and investigate their relationship with acetabular component positioning. Methods. 3D CT imaging was combined with a recently validated method of mapping bearing surface wear in retrieved hip implants. The asymmetrical stabilizing fins of Birmingham hip replacements (BHRs) allowed the co-registration of their acetabular wear maps and their computational models, segmented from CT scans. The in vivo location of edge-wear was measured within a standardized coordinate system, defined using the anterior pelvic plane. Results. Edge-wear was found predominantly along the superior acetabular edge in all cases, while its median location was 8° (interquartile range (IQR) -59° to 25°) within the
Research on hip biomechanics has analyzed femoroacetabular contact pressures and forces in distinct hip conditions, with different procedures, and used diverse loading and testing conditions. The aim of this scoping review was to identify and summarize the available evidence in the literature for hip contact pressures and force in cadaver and in vivo studies, and how joint loading, labral status, and femoral and acetabular morphology can affect these biomechanical parameters. We used the PRISMA extension for scoping reviews for this literature search in three databases. After screening, 16 studies were included for the final analysis.Aims
Methods
Femoroacetabular impingement (FAI) patients report exacerbation of hip pain in deep flexion. However, the exact impingement location in deep flexion is unknown. The aim was to investigate impingement-free maximal flexion, impingement location, and if cam deformity causes hip impingement in flexion in FAI patients. A retrospective study involving 24 patients (37 hips) with FAI and femoral retroversion (femoral version (FV) < 5° per Murphy method) was performed. All patients were symptomatic (mean age 28 years (SD 9)) and had anterior hip/groin pain and a positive anterior impingement test. Cam- and pincer-type subgroups were analyzed. Patients were compared to an asymptomatic control group (26 hips). All patients underwent pelvic CT scans to generate personalized CT-based 3D models and validated software for patient-specific impingement simulation (equidistant method).Aims
Methods
Cite this article:
The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate. This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database.Aims
Methods
Slipped upper femoral epiphysis (SUFE) has well documented biochemical and mechanical risk factors. Femoral and acetabular morphologies seem to be equally important. Acetabular retroversion has a low prevalence in asymptomatic adults. Hips with dysplasia, osteoarthritis, and Perthes’ disease, however, have higher rates, ranging from 18% to 48%. The aim of our study was to assess the prevalence of acetabular retroversion in patients presenting with SUFE using both validated radiological signs and tomographical measurements. A retrospective review of all SUFE surgical cases presenting to the Royal Children’s Hospital, Melbourne, Australia, from 2012 to 2019 were evaluated. Preoperative plain radiographs were assessed for slip angle, validated radiological signs of retroversion, and standardized postoperative CT scans were used to assess cranial and mid-acetabular version.Aims
Methods
The aims of this network meta-analysis (NMA) were to examine nonunion rates and functional outcomes following various operative and nonoperative treatments for displaced mid-shaft clavicle fractures. Initial search strategy incorporated MEDLINE, PubMed, Embase, and the Cochrane Library for relevant randomized controlled trials (RCTs). Four treatment arms were created: nonoperative (NO); intramedullary nailing (IMN); reconstruction plating (RP); and compression/pre-contoured plating (CP). A Bayesian NMA was conducted to compare all treatment options for outcomes of nonunion, malunion, and function using the Disabilities of the Arm Shoulder and Hand (DASH) and Constant-Murley Shoulder Outcome scores.Aims
Methods
The Exeter V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems. A systematic literature search was performed adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. In parallel, we performed a retrospective single centre study of Exeter V40 femoral stem prosthetic fractures between April 2003 and June 2020.Aims
Methods
Femoroacetabular impingement (FAI) is a potential cause of hip osteoarthritis (OA). The purpose of this study was to investigate the expression profile of matrix metalloproteinases (MMPs) in the labral tissue with FAI pathology. In this study, labral tissues were collected from four FAI patients arthroscopically and from three normal hips of deceased donors. Proteins extracted from the FAI and normal labrums were separately applied for MMP array to screen the expression of seven MMPs and three tissue inhibitors of metalloproteinases (TIMPs). The expression of individual MMPs and TIMPs was quantified by densitometry and compared between the FAI and normal labral groups. The expression of selected MMPs and TIMPs was validated and localized in the labrum with immunohistochemistry.Aims
Methods
Femoroacetabular impingement (FAI) describes abnormal bony contact of the proximal femur against the acetabulum. The term was first coined in 1999; however what is often overlooked is that descriptions of the morphology have existed in the literature for centuries. The aim of this paper is to delineate its origins and provide further clarity on FAI to shape future research. A non-systematic search on PubMed was performed using keywords such as “impingement” or “tilt deformity” to find early anatomical descriptions of FAI. Relevant references from these primary studies were then followed up.Aims
Methods
Tibial plateau fractures (TPFs) are complex injuries around the knee caused by high- or low-energy trauma. In the present study, we aimed to define the distribution and frequency of TPF lines using a 3D mapping technique and analyze the rationalization of divisions employed by frequently used classifications. In total, 759 adult patients with 766 affected knees were retrospectively reviewed. The TPF fragments on CT were multiplanar reconstructed, and virtually reduced to match a 3D model of the proximal tibia. 3D heat mapping was subsequently created by graphically superimposing all fracture lines onto a tibia template.Aims
Methods
Evaluate if treating an unstable femoral neck fracture with a locking plate and spring-loaded telescoping screw system would improve construct stability compared to gold standard treatment methods. A 31B2 Pauwels’ type III osteotomy with additional posterior wedge was cut into 30 fresh-frozen femur cadavers implanted with either: three cannulated screws in an inverted triangle configuration (CS), a sliding hip screw and anti-rotation screw (SHS), or a locking plate system with spring-loaded telescoping screws (LP). Dynamic cyclic compressive testing representative of walking with increasing weight-bearing was applied until failure was observed. Loss of fracture reduction was recorded using a high-resolution optical motion tracking system.Aims
Methods
The aim of this study was to investigate the structural integrity of torn and non-torn human acetabular labral tissue. A total of 47 human labral specimens were obtained from a biobank. These included 22 torn specimens and 25 control specimens from patients undergoing total hip arthroplasty with macroscopically normal labra. The specimens underwent dynamic shear analysis using a rheometer to measure storage modulus, as an indicator of structural integrity.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
This pilot study reports the clinical outcomes
of a combination of partial subscapularis tendon transfer and small-head
hemiarthroplasty in patients with rotatator cuff arthropathy. A
total of 30 patients (30 shoulders; eight men and 22 women) with
a mean age of 74 years (55 to 84) were assessed at a mean follow-up
of 31 months (24 to 60). The inclusion criteria were painful cuff
tear arthropathy with normal deltoid function and a non-degenerative subscapularis
muscle and tendon and a preserved teres minor. Outcome was assessed using the University of California Los Angeles
score, the Japanese Orthopaedic Association score, and the Oxford
Shoulder Score. Radiographic measurements included the centre of
rotation distance and the length of the deltoid. All clinical scores were significantly improved post-operatively.
The active flexion and external rotation improved significantly
at the most recent follow-up (p <
0.035). Although the mean centre
of rotation distance changed significantly (p <
0.001), the mean
length of the deltoid did not change significantly from the pre-operative
value (p = 0.29). The change in the length of the deltoid with <
100° flexion was significantly less than that with >
100° (p <
0.001). Progressive erosion of the glenoid was seen in four patients.
No patient required revision or further surgery. A combination of partial subscapularis tendon transfer and small-head
hemiarthroplasty effectively restored function and relieved pain
in patients with rotator cuff arthropathy. Cite this article: 2015;97-B:1090–5.
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
Sagittal alignment of the lumbosacral spine, and specifically pelvic incidence (PI), has been implicated in the development of spine pathology, but generally ignored with regards to diseases of the hip. We aimed to determine if increased PI is correlated with higher rates of hip osteoarthritis (HOA). The effect of PI on the development of knee osteoarthritis (KOA) was used as a negative control. We studied 400 well-preserved cadaveric skeletons ranging from 50 to 79 years of age at death. Each specimen’s OA of the hip and knee were graded using a previously described method. PI was measured from standardised lateral photographs of reconstructed pelvises. Multiple regression analysis was performed to determine the relationship between age and PI with HOA and KOA.Objectives
Methods
Osteoarthritis is extremely common and many different causes for it have been described. One such cause is abnormal morphology of the affected joint, the hip being a good example of this. For those joints with femoroacetabular impingement (FAI) or developmental dysplasia of the hip (DDH), a link with subsequent osteoarthritis seems clear. However, far from being abnormal, these variants may be explained by evolution, certainly so for FAI, and may actually be normal rather than representing deformity or disease. The animal equivalent of FAI is coxa recta, commonly found in species that run and jump. It is rarely found in animals that climb and swim. In contrast are the animals with coxa rotunda, a perfectly spherical femoral head, and more in keeping with the coxa profunda of mankind. This article describes the evolutionary process of the human hip and its link to FAI and DDH. Do we need to worry after all?
The June 2015 Children’s orthopaedics Roundup360 looks at: ACL reconstruction in paediatric knees; Hips, slips and cams; The adolescent clavicle; 3D fluoroscopy in DDH?; The psychiatric aspects of hip pain in adolescents; Adolescent bunions: dealer’s choice?; Medial epicondylar fractures revisited
To quantify and compare peri-acetabular bone mineral density
(BMD) between a monoblock acetabular component using a metal-on-metal
(MoM) bearing and a modular titanium shell with a polyethylene (PE)
insert. The secondary outcome was to measure patient-reported clinical
function. A total of 50 patients (25 per group) were randomised to MoM
or metal-on-polyethlene (MoP). There were 27 women (11 MoM) and
23 men (14 MoM) with a mean age of 61.6 years (47.7 to 73.2). Measurements
of peri-prosthetic acetabular and contralateral hip (covariate)
BMD were performed at baseline and at one and two years’ follow-up.
The Western Ontario and McMaster Universities osteoarthritis index
(WOMAC), University of California, Los Angeles (UCLA) activity score,
Harris hip score, and RAND-36 were also completed at these intervals.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.
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.