Optimising a self-assembling peptide hydrogel as a Matrigel alternative for 3-dimensional mammary epithelial cell culture.

Three-dimensional (3D) organoid models have been instrumental in understanding molecular mechanisms responsible for many cellular processes and diseases. However, established organic biomaterial scaffolds used for 3D hydrogel cultures, such as Matrigel, are biochemically complex and display significant batch variability, limiting reproducibility in experiments. Recently, there has been significant progress in the development of synthetic hydrogels for in vitro cell culture that are reproducible, mechanically tuneable, and biocompatible.

The effect of pain after total knee arthroplasty on the contralateral, nonreplaced knee.

Background: Osteoarthritis is associated with a strong biomechanical component. Persistent pain in the index knee after total knee arthroplasty could lead to pain in the contralateral knee. The purpose of the present study was to examine whether a change in the natural history of pain in the contralateral knee was related to postoperative pain in the index knee.

What advantage is there to be gained using large modular metal-on-metal bearings in routine primary hip replacement? A preliminary report of a prospective randomised controlled trial.

The aim of this study was to investigate the possible benefit of large-head metal-on-metal bearing on a stem for primary hip replacement compared with a 28 mm diameter conventional metal-on-polyethylene bearing in a prospective randomised controlled trial. We investigated cemented stem behaviour between these two different bearings using Einzel-Bild-Röntgen-Analyse, clinical and patient reported measures (Harris hip score, Western Ontario and McMaster Universities osteoarthritis index, Short Form-36 and satisfaction) and whole blood metal ion levels at two years. A power study indicated that 50 hips were needed in each group to detect subsidence of > 5 mm at two years with a p-value of < 0.

Metal-on-metal total hip arthroplasty.

The effects of elevated levels of metal ions in patients who have undergone metal-on-metal total hip arthroplasty are not fully understood. The effects of femoral head size on serum metal-ion levels have been the subject of conflicting reports, and further investigation is needed to evaluate the impact of acetabular and femoral component alignment. The conduct of clinical trials of metal-on-metal total hip arthroplasties has been inadequate as few investigators have used a randomized controlled design to compare metal-on-metal bearings with other bearing surfaces.

Barriers to weight loss in obese patients with knee osteoarthritis.

Introduction: Obesity contributes to the development of knee osteoarthritis and complicates its surgical treatment. The aim of this study was to explore barriers to effective weight management in obese patients with knee osteoarthritis.

Patients And Methods: A cross-sectional questionnaire study was performed in an elective out-patient setting and on an orthopaedic ward on patients with a body mass index (BMI) of 30 kg/m2 or over and knee osteoarthritis.

The prevalence of osteoporosis in patients with severe hip and knee osteoarthritis awaiting joint arthroplasty.

Background: the presence of osteoporosis in patients with hip and knee osteoarthritis (OA) has important implications for understanding disease progression and providing optimal surgical and medical management.

Objective: to determine the prevalence of osteoporosis among patients with osteoarthritis awaiting total knee arthroplasty or total hip arthroplasty aged between 65 and 80 years.

Design: cross-sectional observational study.

Comparison of patient-reported outcomes between hip resurfacing and total hip replacement.

This study compared the demographic, clinical and patient-reported outcomes after total hip replacement (THR) and Birmingham Hip Resurfacing (BHR) carried out by a single surgeon. Patients completed a questionnaire that included the WOMAC, SF-36 scores and comorbid medical conditions. Data were collected before operation and one year after.

All-polyethylene compared with metal-backed tibial components in total knee arthroplasty at ten years. A prospective, randomized controlled trial.

Background: Several studies have described equivalent performance on radiostereometric analysis at two years for metal-backed compared with all-polyethylene stemmed tibial implants. The purpose of this study was to determine the ten-year survivorship results of these two designs from a large randomized controlled trial.

Methods: Patients who were fifty years old or more, with no history of infection, and were undergoing primary total knee arthroplasty were randomized at the time of surgery to receive either an all-polyethylene or a metal-backed tibial component.

Hip flexion after Birmingham hip resurfacing: role of cup anteversion, anterior femoral head-neck offset, and head-neck ratio.

We aimed to investigate the factors affecting range of flexion after hip resurfacing. A total of 82 cases, operated by a single surgeon, were assessed at a mean of 43 months. The Einzel-Bild-Roentgen-Analysis for the acetabular cup software was used to measure socket orientation.

Predicting range of movement after knee replacement: the importance of posterior condylar offset and tibial slope.

We have attempted to quantify the influence of clinical, radiological and prosthetic design factors upon flexion following knee replacement. Our study examined the outcome following 101 knee replacements performed in two prospective randomized trials using similar cruciate retaining implants. Multivariate analyses, after adjusting for age, sex, diagnosis and the type of prosthesis revealed that the only significant correlates for range of movement at 12 months were the difference in posterior condylar offset ratio (p < 0.

Patient-reported outcomes after fixed- versus mobile-bearing total knee replacement: a multi-centre randomised controlled trial using the Kinemax total knee replacement.

We compared patient-reported outcomes of the Kinemax fixed- and mobile-bearing total knee replacement in a multi-centre randomised controlled trial. Patients were randomised to the fixed- or the mobile-bearing prosthesis via a sealed envelope method after the bone cuts had been made in the operating theatre. Randomisation was stratified by centre and diagnosis.

Gender identity and substance use among students in two high schools in Monterrey, Mexico.

This study explored relationships between several hypothesized dimensions of gender identity and substance use outcomes within a non-probability sample of adolescents in Monterrey, Mexico. Based on Mexican concepts of machismo and marianismo, four gender identity constructs were measured: aggressive masculinity, assertive masculinity, affective femininity and submissive femininity. The study assessed how well these gender identity measures predicted substance use behaviors, substance use intentions, expectancies, and normative approval, and exposure and vulnerability to substance offers.

284 press-fit Kinemax total knee arthroplasties followed for 10 years: poor survival of uncemented prostheses.

Background And Purpose: Our institution began using the Kinemax total knee arthroplasty system in 1988, both with and without cement fixation. We report 10-year survival figures.

Methods: Theater records showed that 284 Kinemax total knee arthroplasties had been performed 1988 through 1993.

Outcome following knee arthroplasty beyond 15 years.

There is a paucity of information detailing functional outcome following total knee arthroplasty for this length of follow-up. We collected data from 187 knees in 150 surviving patients, beyond 15 years from implantation. Survival of the implant was confirmed and a patient administered questionnaire including WOMAC, SF-36 and patient satisfaction was used, data was scrutinised for differences between primary and revision knee surgery.

Effects of socioeconomic status on patients' outcome after total knee arthroplasty.

Objective: To identify whether patients in lower socioeconomic groups had worse pain and functional levels prior to total knee arthroplasty and then establish whether these patients had poorer post-operative outcomes following total knee arthroplasty.

Method: Data was obtained from a prospective observational study of 974 patients undergoing primary total knee arthroplasty for osteoarthritis. The study was undertaken in 13 centers in 4 countries.

Venous thromboembolism in patients with primary bone or soft-tissue sarcomas.

Background: Venous thromboembolism has been independently associated with both malignant disease and orthopaedic surgery. Patients with bone or soft-tissue tumors who undergo orthopaedic surgery may therefore be at high risk for thromboembolic events. The purpose of the present retrospective study was to determine the rate of clinically detected deep venous thrombosis and pulmonary embolism in patients with trunk or extremity bone or soft-tissue sarcomas.

Impact of psychological distress on pain and function following knee arthroplasty.

Background: Preoperative psychological distress has been reported to be an important risk factor for poor outcome following lower-extremity arthroplasty. We determined the independent impact of preoperative psychological distress on three, twelve, and twenty-four-month WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) pain and function scores and on change scores over those time periods.

Methods: Data were obtained from an international group of 952 patients in thirteen centers participating in the Kinemax Outcomes Study.

Patient expectations regarding total knee arthroplasty: differences among the United States, United Kingdom, and Australia.

Background: Total knee arthroplasty is an effective treatment for severe osteoarthritis of the knee. Our aim was to determine whether patients from the United Kingdom, United States, and Australia have different preoperative expectations regarding total knee arthroplasty and whether these expectations have an impact on outcomes and patient satisfaction.

Methods: Patients from the United Kingdom, the United States, and Australia were recruited into a prospective observational study of primary total knee arthroplasty for the treatment of osteoarthritis.

Determinants of discharge destination following elective total hip replacement.

Objective: To identify the factors associated with discharge to an inpatient rehabilitation facility versus discharge directly to home after elective total hip replacement (THR).

Methods: Data were obtained from a medical record review and a cross-sectional survey of a population-based cohort of patients who received elective primary or revision THR in 1995. Postoperative functional status was measured as the ability to walk independently prior to discharge.

Patient-reported outcome and survivorship after Kinemax total knee arthroplasty.

Background: We examined the long-term survivorship and patient-reported outcomes at a minimum of ten years following primary total knee arthroplasty. We hypothesized (1) that the survival rate would be at least 90% at ten years; (2) that age, gender, body-mass index, and primary diagnosis would not affect the survival rate; and (3) that the functional status of patients would be comparable with that of an age and gender-matched normal population.

Methods: A total of 407 patients (523 knees) who had had primary total knee arthroplasty between January 1988 and April 1991 were identified.

Psychosocial and geriatric correlates of functional status after total hip replacement.

Objective: To determine whether psychosocial factors, chronic diseases, and common geriatric problems are associated with poor physical function 3 years after primary total hip replacement (THR).

Methods: We studied a sample of Medicare recipients in Ohio, Pennsylvania, and Colorado (n = 922) who underwent primary THR in 1995 (mean +/- SD age 73.1 +/- 5.

Predicting the outcome of total knee arthroplasty.

Background: The relief of pain and the restoration of functional activities are the main outcomes of primary total knee arthroplasty for the treatment of osteoarthritis. This paper examines the preoperative predictors of pain and functional outcome at one and two years following total knee arthroplasty.

Methods: Patients were recruited for a prospective observational study of primary total knee arthroplasty for the treatment of osteoarthritis from centers in the United States, the United Kingdom, and Australia.

Management and care of patients undergoing total knee arthroplasty: variations across different health care settings.

Objectives: To examine variation in the process of care for total knee arthroplasty (TKA) and to highlight the need for rigorous research into the ideal management of TKA. We hypothesize that variation in the process of care for TKA across and within health care systems is associated with identifiable financial and historical factors.

Methods: We compared access to TKA and typical postoperative rehabilitation management in 12 orthopedic centers in the United States (4 centers), United Kingdom (6 centers), and Australia (2 centers).