RESULTS During the study period, 1,303 patients received primary THA. 338 (25.9%) were eligible for day-surgery, but 17 (5%) declined; the day-surgery series thus comprised 321 patients (24.6%) 166 men, 155 women; mean age, 61.2±9.7 years. Same-day discharge was not possible for 14 patients (4.5%) 9 due to persistent faintness, 2 to intraoperative femoral fracture, 1 to organizational issues, 1 to an uncomplicated fall, and 1 to hemoglobinemia less then 11g/100ml in a coronary patient. There were no readmissions during week 1. At 6 weeks' follow-up, there had been 3 adverse events 2 dislocations, and 1 periprosthetic fracture. 312 patients (97.2%) were satisfied. CONCLUSION The present prospective study found no major adverse events in patients undergoing day-surgery for primary THA. However, patients should be selected, consenting, prepared and managed on a standardized clinical pathway. LEVEL OF EVIDENCE IV; non-comparative prospective study. BACKGROUND Restoration of the constitutional joint anatomy after hip replacement favours physiological peri-articular soft-tissue tension and kinematics, and is likely to be functionally beneficial. Hip resurfacing (HR) and conventional total hip replacement (THR) are two different options for replacing degenerated hips, and are likely to result in different anatomical reconstruction. We initiated this study to investigate the differences in gait performance between these two prosthetic options, and aimed to answer the following questions (1) does HR result in better restoration of the frontal hip anatomical parameters, (2) and generate a more physiological gait compared to THR? (3) Does the quality of the anatomical restoration after THR influence gait performance? HYPOTHESES Our hypothesis was that a better anatomical restoration using HR versus THR would produce more physiological (symmetric) gait. METHODS We retrospectively reviewed 52 patients who had unilateral primary osteoarthritis successfully treateffset. Under normal conditions (normal walking speed and flat ramp), the gait was fairly symmetric for both the HR and the THR patients with a symmetry index of 0.62% and 3.14% respectively. At high walking speed (stress conditions), the symmetry index degraded for both groups, but the gait remained more symmetric in the HR group (2.09%), compared to the THR group (5.74%); nevertheless, the difference remained not statistically significant (p=0.159). We were unable to detect any significant relationship between gait performances and radiographically measured hip frontal anatomical parameters. DISCUSSION/CONCLUSIONS HR procedure is more consistent than conventional THR in generating a more physiological gait under stress conditions. Radiographic estimation of the quality of the frontal anatomical hip restoration is of poor value to predict gait performances of THR patients. LEVEL OF EVIDENCE III - retrospective case-control study with prospective data collection. The Self-Administered Comorbidity Questionnaire (SCQ) is a tool used by hospitalized patients to self-report their comorbidities. It can help to explain the effectiveness of hip or knee arthroplasty, its complications, the length of hospital stay and perioperative resource utilization. HYPOTHESIS The French-Canadian version of the SCQ will be suitable for use in a Canadian hospital population. OBJECTIVES (1) translate and evaluate the transcultural validity of the SCQ in a French Canadian population undergoing hip or knee arthroplasty; (2) determine the standard error of measurement (SEM) in the French Canadian version. MATERIALS AND METHODS The translation and transcultural adaptation process consisted of four steps (1) initial translation; (2) back translation; (3) assessment of questionnaire clarity with patients; (4) assessment of the translation's transcultural validity.  https://www.selleckchem.com/products/PD-98059.html  The SEM was also calculated. RESULTS Twenty participants were recruited for step 3 and 83 participants for step 4. The original English version of the SCQ and the translated French-Canadian version (SCQ-FC) were similar with intra-class correlation coefficients for the intra-language and inter-language agreement between 0.71 and 0.97. The SEM was 1.92. CONCLUSION The SCQ-FC is comparable to the original English language version. Using this questionnaire allows us to document the comorbidities present in patients undergoing hip and knee arthroplasty in a French-Canadian population, and the impact of these comorbidities on the patients' health. LEVEL OF EVIDENCE V, Prospective study. BACKGROUND The effect of age on the percentage of primary knee replacements appropriate for unicompartmental replacement (UKR), defined as candidacy, is unknown. The aim was to determine the candidacy and outcome of UKR in different age groups. HYPOTHESIS Age is associated with candidacy for medial UKR. PATIENTS AND METHODS This cross-sectional study determined UKR candidacy from preoperative radiographs, including stress views, from 457 consecutive knee replacements (TKR or UKR) in a specialist joint replacement centre. Candidacy, estimated from radiographs and from usage, was determined for all knees and then stratified by age group less then 50, 50-60, 60-70, 70-80, and 80+. The outcome of UKR implanted in these groups was also assessed. To avoid overestimating, candidacy estimated by usage was used for the primary analysis. RESULTS Candidacy decreased with age (OR 0.98, p=0.008) and was 61% (CI 42-78), 52% (CI 43-61), 43% (CI 35-51), 41% (CI 31-52), and 36% (CI 22-52) respectively. Candidacy estimated by radiographs was slightly higher overall (49% compared to 46%) and in all age groups than candidacy estimated from usage. Neither functional outcome (p=0.47) nor implant survival (p=0.54) was affected by age. Overall 80% achieved good/excellent Knee Society objective scores, and the five-year implant survival was 99%. DISCUSSION There is a strong association of candidacy for UKR with age in that younger patients are more likely to be candidates (61% in those less then 50 and 36% in those 80+). Good outcomes can be expected in patients of all ages who are appropriate for UKR. LEVEL OF EVIDENCE IV, Prognostic cross-sectional study. Crown All rights reserved.