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Purpose. To evaluate active and functional knee excursion of patients before and after total knee arthroplasty (TKA) and to determine whether TKA restores quality of life related to functional activities of daily living. Methods. Electrogoniometry was used to measure the functional movement of the knee during 11 activities of daily living in 50 patients who underwent TKA. These data were compared with the patient's active range of motion and quality-of-life scores. Results. A cut-off point existed between loss and gain in flexion at between 90 and 95 degrees of preoperative active flexion. Two thirds of patients had preoperative flexion of more than 90 degrees, 83% of them had reduced flexion postoperatively. The remaining one third had preoperative flexion of 90 degrees or less, 85% of them had improved flexion postoperatively. A similar pattern of loss and gain occurred for functional movement of the knee. Reduced functional range was associated with significantly reduced physical quality of life compared with age-matched healthy subjects. Conclusion. Although TKA offers excellent pain relief and contributes to the overall well-being of the patient, these results suggest that it also leads to a reduced range of active and functional motion in the majority of patients. This is associated with a lower-than-normal physical quality of life. The design of implants and rehabilitation programmes should be reconsidered so that better range of motion and quality of life can be achieved for patients.

Background: The primary aim was to assess survival of opening wedge high tibial osteotomy (HTO) for medial compartment osteoarthritis. The secondary aim was to identify independent predictors of early conversion to total knee arthroplasty (TKA)., Methods: During the 18-year period (1994-2011) 111 opening wedge HTO were performed at the study centre. Mean age was 45 years (range 18-68) and the majority male (84%). Mean follow-up was 12 (range six to 21) years. Failure was defined as conversion to TKA. Kaplan-Meier, Cox regression and receiver operating curve (ROC) analyses were performed., Results: Forty (36.0%) HTO failed at a mean of 6.3 years (range one to 15). By Kaplan-Meier analysis, the five-year survival rate was 84% (95% confidence interval (CI) 82.6-85.4), 10-year rate 65% (95% CI 63.5-66.5) and 15-year rate 55% (95% CI 53.3-56.7). Cox regression analysis identified older age (hazard ratio (HR) 1.07 for each additional year, 95% CI 1.03-1.11, p b 0.001) and female gender (HR 2.37, 95% CI 1.06-5.33, p = 0.04) as independent predictors of failure. ROC analysis identified a threshold age of 47 years above which the risk of failure increased significantly (area under curve 0.72, 95% CI 0.62-0.81, p b 0.001). Cox regression analysis, adjusting for covariates, identified a significantly greater (HR 2.49, 95% CI 1.26-4.91, p = 0.01) risk of failure in patients aged 47 years old or more., Conclusion: The risk of early conversion to TKA is significantly increased in females and those older than 47. These risk factors should be considered pre-operatively when planning intervention for isolated medial compartment osteoarthritis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The low contact stress (LCS) mobile-bearing total knee replacement (TKR) was designed to minimise polyethylene wear, aseptic loosening and osteolysis. However, registry data suggests there is a significantly greater revision rate associated. The primary aim of this study was to assess long-term survivorship of the LCS TKR performed at a single high-volume centre. Secondary aims were to assess survival by mechanism of failure and identify predictors of revision., Methods: During a 13-year period (1993-2006) 1091 LCS TKRs were performed by two senior surgeons. Thirty-three with incomplete data were excluded. The patients were retrospectively identified from an arthroplasty register. Mean age was 69 (range 30-96) years. Five hundred seventy-seven TKRs were performed in females, 481 in males. Mean follow-up was 14 years (SD 4.3)., Results: There were 59 revisions during the study period: 14 (23.7%) for infection, 18 (30.5%) for instability, and 27 (45.8%) for polyethylene wear. Three hundred ninety-two patients died. All-cause survival at 10 years was 95% (95%CI 91.7-98.3) and at 15 years was 93% (95%CI 88.6-97.8). Survival at 10 years according to mechanism of failure was: infection 99% (95%CI 94-100%), instability 98% (95%CI 94-100%), and polyethylene wear 98% (95%CI 92-100). Of the 27 with polyethylene wear, only 19 (70.4%) had osteolysis requiring component revision, the other eight (29.6%) had polyethylene exchanges. Cox regression analysis identified younger age as the only predictor of revision (HR 0.96, 95%CI 0.94-0.99, p = 0.003), with a four percent decreased risk of revision for each increase in year of age., Conclusions: The LCS TKR demonstrates excellent long-term survivorship with a low rate of revision for osteolysis, however this risk is increased in younger patients., (Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.)

Range of motion following total knee arthroplasty (TKA) is a crucial measure of clinical outcome. The purpose of this randomized, controlled study was to determine which factors are predictive of postoperative range of flexion. Fifty-six patients received either a standard or a high-flexion design NexGen Legacy Posterior-Stabilized TKA (Zimmer, Warsaw, Indiana). The relationship between preoperative flexion, intraoperative flexion, and range of flexion 1 year postoperatively was determined. The influence of soft tissue release and the type of femoral component was also investigated. A significant correlation existed between preoperative flexion, intraoperative flexion, and maximum flexion 1 year postoperatively. Patients who had a preoperative range of flexion less than the mean range of flexion for the overall group gained flexion, whereas patients with a preoperative range of flexion greater than the mean range of flexion lost flexion. The degree of soft tissue release performed and the type of implant used had no influence on maximum flexion at 1 year. The principal predictive factor of postoperative range of flexion, regardless of the degree of soft tissue release or implant design, is the preoperative and intraoperative range of flexion.

Purpose: To evaluate active and functional knee excursion of patients before and after total knee arthroplasty (TKA) and to determine whether TKA restores quality of life related to functional activities of daily living., Methods: Electrogoniometry was used to measure the functional movement of the knee during 11 activities of daily living in 50 patients who underwent TKA. These data were compared with the patient's active range of motion and quality-of-life scores., Results: A cut-off point existed between loss and gain in flexion at between 90 and 95 degrees of preoperative active flexion. Two thirds of patients had preoperative flexion of more than 90 degrees, 83% of them had reduced flexion postoperatively. The remaining one third had preoperative flexion of 90 degrees or less, 85% of them had improved flexion postoperatively. A similar pattern of loss and gain occurred for functional movement of the knee. Reduced functional range was associated with significantly reduced physical quality of life compared with age-matched healthy subjects., Conclusion: Although TKA offers excellent pain relief and contributes to the overall well-being of the patient, these results suggest that it also leads to a reduced range of active and functional motion in the majority of patients. This is associated with a lower-than-normal physical quality of life. The design of implants and rehabilitation programmes should be reconsidered so that better range of motion and quality of life can be achieved for patients.

We used electrogoniometers to measure the range of movement (ROM) of the knee during various activities, comparing 50 patients with osteoarthritis of the knee (OA) with 20 healthy age- and sex-matched subjects. The minimum and maximum joint angles and the ranges of excursion of the patient and control groups were tested for significant differences, using an unrelated Student's t-test with pooled variance. Knee flexion in patients with OA was significantly reduced during all activities (p < 0.05), but differences in knee extension were not significant except when patients negotiated stairs. We believe that this reduction in ROM is caused by inhibition due to pain when load-bearing. Static non-load-bearing measurements of the ROM poorly reflected the functional ROM, with a coefficient of determination (r2) of 0.59 in the patient group and 0.60 in the control group. Electrogoniometry of the ROM of the knee provides a reliable, accurate and objective measurement of knee function.

The knee joint kinematics of a group (n=20) of elderly normal subjects (mean age=67 years) were investigated using flexible electrogoniometry. The flexion-extension angle of the knee was recorded during a range of functional activities performed as part of a circuit in and around the hospital. The functions analysed including gait, walking on slopes, stair negotiation, the use of standard and low chairs and a bath. The data were used to produce the pattern of joint angulation against the percentage of the cycle for each individual conducting each activity. Further the maximum and minimum knee joint angles and the excursion of the joint during the cycle were identified. The results indicate gait and slopes require less than 90 degrees of knee flexion, stairs and chairs 90-120 degrees of flexion and a bath approximately 135 degrees of flexion. The data suggests that 110 degrees of flexion would seem a suitable goal for the rehabilitation of motion in the knee. It is concluded that flexible electrogoniometry is a suitable and practical method for evaluating knee motion during a range of functional activities.