Handle With Care: The Anterior Hip Capsule Plays a Key Role in Daily Hip Performance.

Background: Passive energy storage and return has long been recognized as one of the central mechanisms for minimizing the energy cost needed for terrestrial locomotion. Although the iliofemoral ligament (IFL) is the strongest ligament in the body, its potential role in energy-efficient walking remains unexplored.

Purpose: To identify the contribution of the IFL to the amount of work performed by the hip muscles for normal, straight-level walking.

Fracture risk during extraction of well-fixed extended cementless stems : porous versus hydroxyapatite coated.

The concern of extensive fracturing and bone damage during implant removal has been reported for ingrowing stems, in particular in extended porous coated stems, potentially impeding successful re- implantation of a femoral revision implant and consequently debilitating patients for life. The aim of the present study is to describe this particular complication and comparing the occurrence in porous coated and hydroxyapatite (HA) coated femoral implants. 62 consecutive revision hip replacements were per- formed between January 2010 and December 2016 at a single academic institution.

Personalized hip joint kinetics during deep squatting in young, athletic adults.

The goal of this study was to report deep squat hip kinetics in young, athletic adults using a personalized numerical model solution based on inverse dynamics. Thirty-five healthy subjects underwent deep squat motion capture acquisitions and MRI scans of the lower extremities. Musculoskeletal models were personalized using each subject's lower limb anatomy.

Conventional versus direct magnetic resonance imaging in detecting labral lesions in femoroacetabular impingment - a retrospective multicenter study.

The purpose of this study was to assess the reliability of Direct Magnetic Resonance Arthography (MRA) and Conventional Magnetic Resonance Imaging (MRI) in diagnosing labral lesions in patients with symptoms of femoroacetabular impingement (FAI). Materials and methods: Imaging and surgical data (n=490) were retrospectively collected from 5 high-volume centres providing arthroscopic treatment of FAI patients. Preoperative magnetic resonance imaging findings were compared with the actual surgical findings regarding labral condition in order to assess the effectiveness of MRI and MRA in identifying the presence of labral tears in patients with FAI.

Dual-mobility socket in challenging total hip arthroplasty: 2-6 years follow-up.

The success of dual-mobility sockets in achieving implant stability in primary hip replacement is already well established. However, stability cannot always be achieved, especially when dealing with more difficult indications. At our department, 104 dual-mobility sockets (92 uncemented and 12 cemented) were implanted for primary total hip arthroplasty in 97 patients between 2009 and 2013.

The History of Biomechanics in Total Hip Arthroplasty.

Biomechanics of the hip joint describes how the complex combination of osseous, ligamentous, and muscular structures transfers the weight of the body from the axial skeleton into the appendicular skeleton of the lower limbs. Throughout history, several biomechanical studies based on theoretical mathematics, , as well as models have been successfully performed. The insights gained from these studies have improved our understanding of the development of mechanical hip pathologies such as osteoarthritis, hip fractures, and developmental dysplasia of the hip.

Contamination risk of synovial biopsy cultures in total hip arthroplasty: a prospective review of 100 cases.

Introduction: Cultures of deep synovial biopsies remain an important tool in diagnosing periprosthetic joint infection, a devastating complication following total hip arthroplasty (THA). Recent reports of unexpected positive intraoperative cultures in aseptic revision arthroplasty, however, challenge the validity and interpretation of these cultures. The aim of this study was to evaluate the contamination risk of synovial biopsy cultures collected intraoperatively during primary THA of healthy subjects.

Accuracy of navigated cam resection in femoroacetabular impingement: A randomised controlled trial.

Background: The main cause for revision hip arthroscopy surgery is incomplete bony resection of femoroacetabular impingement (FAI). This study aimed to compare the cam resection accuracy via the conventional hip arthroscopy technique with the navigation technique.

Methods: Two prospectively randomized groups were recruited: navigated (n = 15) and conventional (n = 14).

Optimization of a model of out-of-hospital antibiotic therapy (OPAT) in a Belgian university hospital resulting in a proposal for national implementation.

Objectives: Some infections require prolonged parenteral antimicrobial therapy, which can be continued in an outpatient setting. The Ghent University Hospital has 15 years of experience with Outpatient Parenteral Antimicrobial Therapy (OPAT) in the home setting of the patient.

Methods: Multidisciplinary critical approach through identification of areas for improvement with the existing OPAT process within the Ghent University Hospital.

Patient-specific assessment of dysmorphism of the femoral head-neck junction: a statistical shape model approach.

Background: Objective quantification of anatomical variations about the femur head-neck junction in pre-operative planning for surgical intervention in femoro-acetabular impingement is problematic, as no clear definition of average normal anatomy for a specific subject exists.

Methods: We have defined the normal-equivalent of a subject's anatomy by using a statistical shape model and geometric shape optimization for finding correspondences, while excluding the femoral head-neck junction during the fitting procedure. The presented technique was evaluated on a cohort of 20 patients.

Prevalence of radiographic parameters predisposing to femoroacetabular impingement in young asymptomatic Chinese and white subjects.

Background: Osteoarthritis of the hip is five to ten times more common in white people than in Chinese people. Little is known about the true prevalence of femoroacetabular impingement or its role in the development of osteoarthritis in the Chinese population. A cross-sectional study of both white and Chinese asymptomatic individuals was conducted to compare the prevalences of radiographic features posing a risk for femoroacetabular impingement in the two groups.

Distinct dysregulation of the small leucine-rich repeat protein family in osteoarthritic acetabular labrum compared to articular cartilage.

Objective: Articular cartilage is well studied in osteoarthritis (OA). However, the role of supporting structures, such as the acetabular labrum, a sealing structure surrounding the hip joint, has been investigated much less. We recently showed that fibrochondrocytic labrum cells are metabolically active.

Histologic assessment of acetabular labrum healing.

Purpose: The purpose of this study was to histologically examine the human healing response of arthroscopically repaired acetabular labrum tears.

Methods: Biopsy specimens were retrieved from 6 patients during total hip arthroplasty after clinical failure of the index arthroscopic procedure. All patients were diagnosed as having femoroacetabular impingement with a concomitant labral tear.

Early complications after revision total hip arthroplasty with cemented dual-mobility socket and reinforcement ring.

Encouraged by the success of dual-mobility sockets in achieving implant stability in primary hip replacement, surgeons have started to use the implant in revision hip arthroplasty. However, very little is known yet about the postoperative complication rate of this type of implant when fixation in a reinforcement ring is required. In our department, 37 dual-mobility sockets were cemented in a reinforcement ring for revision hip arthroplasty in 36 patients over a period of two years.

Range of motion in femoroacetabular impingement.

Recent epidemiological studies have demonstrated that radiographic features specific to femoroacetabular impingement appear far more frequently in healthy and asymptomatic cohorts than previously anticipated. It remains unclear how incidental findings should be interpreted clinically. In addition, several authors have suggested that a decreased range of motion is part of the clinical presentation of femoroacetabular impingement.

Intramedullary fixation of intertrochanteric hip fractures: a comparison of two implant designs. A prospective randomised clinical trial.

We report the results of a prospective randomized clinical trial comparing the Gamma 3 nail with the ACE trochanteric nail for the treatment of pertrochanteric femoral fractures. One hundred and twelve consecutive patients were enrolled in the study: 61 patients were treated with the Gamma 3 nail, 51 with the ACE trochanteric nail. The two groups were matched for age, fracture type and preoperative Merle d'Aubigné hip score.

Hip morphological characteristics and range of internal rotation in femoroacetabular impingement.

Background: Radiographic features specifically related to the occurrence of femoroacetabular impingement (FAI) appear to be highly prevalent in the asymptomatic population. It remains unclear, however, how these incidental findings should be interpreted clinically and which other variables might differentiate between true incidental findings and preclinical patients.

Purpose: To study the association between cam and overall hip morphological characteristics and range of motion in impingement patients, asymptomatic patients (healthy patients with radiographic features specific to FAI), and healthy controls.

Revision hip arthroplasty using a cementless modular tapered stem.

Purpose: Here we report the short-term clinical and radiological results of the Profemur®-R cementless modular revision stem.

Methods: Between June 2002 and May 2006, 68 revision hip arthroplasties were consecutively performed using this stem. Survival at a mean follow-up of 5.

Can we predict the natural course of femoroacetabular impingement?

We conducted a multivariate regression analysis (including both radiographic and activity related variables) in patients with osteoarthritis of the hip and structural changes related with femoroacetabular impingement. The purpose of this study was to investigate whether the age at which total hip arthroplasty may have to be performed, can be predicted in patients with femoroacetabular impingement (FAI). In 121 patients with FAI-related osteoarthritis, radiographic variables describing FAI-related parameters were obtained and the patients were questioned about their activity during early adulthood by means of the validated Baecke et al questionnaire.

Preformed gentamicin spacers in two-stage revision hip arthroplasty: functional results and complications.

Two-stage revisions with antibiotic-loaded spacers have gained popularity for treating infected hip-joint arthroplasties. The aim of this prospective study was to assess patient functionality between stages and treatment impact on duration of hospital stay and to describe related complications. Sixty-one consecutive patients with infected hip arthroplasties underwent two-stage revision with preformed spacer implantation.

Three-dimensional assessment of cam engagement in femoroacetabular impingement.

Purpose: The purpose of our study was to 3-dimensionally assess cam engagement in male patients with symptomatic femoroacetabular impingement during motion.

Methods: A total of 13 hips with cam-type impingement were investigated. Patient anatomy and clinical range of motion were determined.

Development of a three-dimensional detection method of cam deformities in femoroacetabular impingement.

Objective: The description of femoral head sphericity and related risk for femoroacetabularimpingement is currently limited to an angular estimate-the alpha angle-whose relevance and accuracy have been challenged. We developed a three-dimensional approach for both automated digital measurement of the alpha angle and the detection of camdeformities. Accuracy and diagnostic relevance of the alpha angle estimated by means of the oblique axial and multiple radial plane protocol were compared with the computed results.

Whole blood metal ion concentrations in correlation with activity level in three different metal-on-metal bearings.

Seventy consecutive osteoarthritis patients younger than 65 years undergoing a hip arthroplasty were included. Three different metal bearings were used (2 different resurfacing systems and one 28-mm metal bearing) and compared with a ceramic control group. Whole blood cobalt and chromium levels were analyzed preoperatively, at 3 months, 6 months, 1 year, and 2 years.

Balloon dissection for improved access to the peritrochanteric compartment.

Nonarthritic, trochanteric pain is a commonly encountered orthopaedic condition. Although most patients respond to conservative treatment, those with recalcitrant symptoms may require surgical intervention. Studies have successfully explored the use of the arthroscope in the treatment of these patients.

Complications encountered with the use of constrained acetabular prostheses in total hip arthroplasty.

At our department, 46 constrained acetabular components in 38 patients were placed successively for a period of 4 years. Indications included recurrent dislocation, septic and aseptic loosening with extensive bone loss, tumor surgery with extensive bone resection, and instability due to neurologic impairment. Because 2 cup failures and 10 dislocations were observed with the constrained devices at 4 to 7 years of follow-up, the authors started to use large-diameter metal-on-metal bearings for similar indications.