The Validity, Reliability, Measurement Error, and Minimum Detectable Change of the 30‐Second Fast‐Paced Walk Test in Persons with Knee Osteoarthritis: A Novel Test of Short‐Distance Walking Ability

Objective To develop and establish the reliability, validity, measurement error, and minimum detectable change of a novel 30‐second fast‐paced walk test (30SFW) in persons with knee osteoarthritis (OA) that is easy to administer and can quantify walking performance in persons of all abilities. Methods Twenty females with symptomatic knee OA (mean age [SD] 58.30 [8.05] years) and 20 age‐ and sex‐matched asymptomatic controls (57.25 [8.71] years) participated in the study. Participants completed questionnaires of demographic and clinical data, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the 36‐item Short Form Health Survey (SF‐36) followed by 30SFW performance. Participants returned 2‐7 days later and performed the 30SFW again. Results The knee OA group reported function that was worse than controls (all KOOS subscales; P \u3c 0.0001). The 30SFW intrarater and interrater reliability were excellent [ICC(2,1) = 0.95‐0.99]. Knee OA participants walked a shorter distance in the 30SFW than controls (mean [SD]: OA 44.4 m [9.5 m]; control 58.1 m [7.8 m]; P \u3c 0.0001). Positive strong correlations were found between the 30SFW and the KOOS–Activity of Daily Living, SF‐36‐Physical Functioning, and SF‐36‐Physical Health Composite scores (P \u3c 0.0001). A nonsignificant, weak correlation between 30SFW and SF‐36‐Mental Health scores was present (r = 0.32, P = 0.05). Conclusion The 30SFW has excellent intrarater and interrater reliability. The 30SFW demonstrated excellent known groups, convergent, and discriminant validity as a measure of short‐distance walking ability in persons with knee OA. Clinicians and researchers should consider using the 30SFW to quantify walking ability in persons with knee OA and assess walking ability change

The Work of the Alien Property Custodian

The aim of the thesis was to investigate deficits and compensatory strategies after total knee arthroplasty (TKA) in different conditions during gait and quiet standing. Although TKA is considered the gold standard treatment for end-stage knee osteoarthritis, it is associated with a number of implications. Reduced physical function after osteoarthritis is partly, but apparently not fully, remedied by surgery. The two most common deficits are reduced knee muscle strength and limited range of knee joint motion (ROM), partly due to prosthesis mechanics. Reduced postural control has also been shown shortly after surgery. In spite of sufficient passive knee joint ROM for normal ambulation, gait patterns are characterized by reduced knee flexion. Several factors such as reduced knee muscle strength, reduced proprioception, habitual strategies or fear of movement may be suggested as explanations for difficulties in gait and posture. As an effect, compensatory strategies may result. In order to focus on the implications of TKA, participants had to be less than 65 years of age and healthy, TKA being the only factor different form controls. The same 23 individuals with unilateral TKA ~ 19 months post-operative and 23 controls participated in all studies.   3D whole body kinematics was used to assess gait and posture and electromyography was used to record muscle activity. Isokinetic measurements were used to determine dynamic knee muscle strength. Gait in the frontal and sagittal planes were assessed. The tasks included in the test protocol were negotiation up and down stairs, gait on hard and soft surface, quiet standing with sensory modulation (with and without vision and on soft surface), and single limb stance.  Primary outcome variables addressed were: knee and hip joint kinematics in frontal and sagittal planes, upper body inclination, postural sway and relative knee muscle activity as an indicator of relative effort. Background factors used to explain group differences in the primary outcomes were derived from demographics, clinical examination, and questionnaires. Demographic factors were age, body mass index (BMI), and time since surgery. Clinical examinations were conducted for passive knee joint ROM, joint position sense, knee muscle strength, anterior knee joint laxity, and leg length. Questionnaires assessed fear of movement, pain, and knee related function and quality of life. The results showed that knee flexion was reduced during stair descent in both the prosthetic and the contralateral knee in the TKA group compared to controls. Although reduced passive knee joint flexion in the TKA group was sufficient for normal stair descent, it was the only factor identified that explained reduced knee flexion in stair descent. As knee muscle strength was significantly reduced in the TKA group, it is reasonable to suggest that as a contributing factor. Furthermore, the TKA group also displayed increased hip adduction during stair descent, which may indicate both a compensatory strategy as well as reduced hip muscle strength. In stair ascent, no significant group differences were found in relative knee muscle activity as expected due to knee muscle weakness. Nor were there any indications of compensatory forward inclination of the trunk to reduce knee joint moments. Instead, probably compensating for muscle weakness, the TKA group ascended stairs at a significantly slower speed. Surface modulation during level gait showed that reduced knee flexion in the prosthetic knee during the stance phase when walking on a hard surface was further decreased during gait on a soft surface. Knee and hip adduction at the stance phase were not affected by surface conditions. Nevertheless, the TKA group displayed increased knee adduction and hip adduction compared to controls, particularly in the prosthetic side. In addition, the TKA group displayed increased step width on the soft compared to hard surface. Single-limb stance for 20 seconds failed in 30 % of the TKA group and in 4 % of the control group. Those in the TKA group who were able to perform single-limb stance performed equally well as controls. During bilateral quiet standing, postural sway was similar in both groups, and inability to stand on one leg did not affect bilateral stance. Older age, higher BMI and reduced quadriceps strength determined the failure to maintain single-limb stance in the TKA group.   In conclusion, this thesis indicates that reduced knee muscle strength is a common denominator as part of the explanatory factors for reduced performance and compensatory strategies in individuals with TKA. Reduced speed during stair ascent as well as reduced knee flexion during stair descent may be compensations for reduced lower extremity strength. Increased hip adduction may compensate for reduced knee flexion in stair descent, but may also represent hip muscle weakness or reduced motor control as increased hip adduction is found also in level gait. The failure to maintain single-limb stance in the TKA group is also partly explained by reduced knee muscle strength. Muscle weakness may be and indicator for reduced physical capacity in general

Is home-based, high-intensity interval training cycling feasible and safe for patients with knee osteoarthritis? Study protocol for a randomized pilot study

Background: Osteoarthritis (OA) is a degenerative joint disease affecting the knee joint of many middle-aged and older adults. As OA symptoms typically involve knee pain and stiffness, individuals with knee OA are often insufficiently physically active, have low levels of physical function, and are at increased risk of other comorbidities and reduced quality of life. While moderate-intensity continuous training (MICT) cycling is often recommended, little is known about the feasibility, safety, and benefits of high-intensity interval training (HIIT) cycling for this population, even though the feasibility, safety, and benefits of HIIT have been demonstrated in other chronic disease groups. Purpose: The primary objective of this pilot study was to examine the feasibility and safety of home-based HIIT and MICT cycling in middle-aged and older adults with knee OA. A secondary objective was to gain some insight into the relative efficacy of HIIT and MICT for improving health status (pain, stiffness, and disability), muscle function, and body composition in this population. This study protocol is being published separately to allow a detailed description of the research methods, explain the rationale for choosing the methodological details, and to stimulate consideration of the best means to simulate a research protocol that is relevant to a real-life treatment environment. Study Design: Randomized pilot study protocol. Methods: This trial sought to recruit 40 middle-aged and older adults with knee OA. Participants were randomly allocated to either continuous (MICT) or HIIT home-based cycle training programs, with both programs requiring the performance of 4 cycling sessions (approximately 25 minutes per session) each week. Participants were measured at baseline and postintervention (8 weeks). Feasibility and safety were assessed by adherence rate, dropout rate, and number of adverse events. The relative efficacy of the cycling programs was investigated by 2 knee OA health status questionnaires (Western Ontario and McMaster Universities Osteoarthritis Index scale[WOMAC] and the Lequesne Index) as well as the timed up and go, sit to stand, preferred gait speed, and body composition. Discussion: This pilot study appears to be the first study assessing the feasibility and safety of a home-based HIIT training program for middle-aged and older adults with knee OA. As HIIT has been demonstrated to be more effective than MICT for improving aspects of health status, body composition, and/or muscular function in other chronic disease groups, the current study has the potential to improve patient outcomes and inform the design of future randomized controlled trials

Predicting dissatisfaction following total knee replacement:a prospective study of 1217 patients

Up to 20% of patients are not satisfied with the outcome following total knee replacement (TKR). This study investigated the pre- and post-operative predictors of dissatisfaction in a large cohort of patients undergoing TKR. We assessed 1217 consecutive patients between 2006 and 2008 both before operation and six months after, using the Short-form (SF)-12 health questionnaire and the Oxford Knee Score. Detailed information concerning comorbidity was also gathered. Satisfaction was measured at one year when 18.6% (226 of 1217) of patients were unsure or dissatisfied with their replacement and 81.4% (911 of 1217) were satisfied or very satisfied. Multivariate regression analysis was performed to identify independent predictors of dissatisfaction. Significant (p &lt; 0.001) predictors at one year included the pre-operative SF-12 mental component score, depression and pain in other joints, the six-month SF-12 score and poorer improvement in the pain element of the Oxford Knee Score. Patient expectations were highly correlated with satisfaction. Satisfaction following TKR is multifactorial. Managing the expectations and mental health of the patients may reduce dissatisfaction. However, the most significant predictor of dissatisfaction is a painful total knee replacement.</p

The Knee Arthroplasty Trial (KAT) : design features, baseline characteristics and two-year functional outcomes after alternative approaches to knee replacement

Background: The aim of continued development of total knee replacement systems has been the further improvement of the quality of life and increasing the duration of prosthetic survival. Our goal was to evaluate the effects of several design features, including metal backing of the tibial component, patellar resurfacing, and a mobile bearing between the tibial and femoral components, on the function and survival of the implant. Methods: A pragmatic, multicenter, randomized, controlled trial involving 116 surgeons in thirty-four centers in the United Kingdom was performed; 2352 participants were randomly allocated to be treated with or without a metal backing of the tibial component (409), with or without patellar resurfacing (1715), and/or with or without a mobile bearing (539). Randomization to more than one comparison was allowed. The primary outcome measures were the Oxford Knee Score (OKS), Short Form-12, EuroQol-5D, and the need for additional surgery. The results up to two years postoperatively are reported. Results: Functional status and quality-of-life scores were low at baseline but improved markedly across all trial groups following knee replacement (mean overall OKS, 17.98 points at baseline and 34.82 points at two years). Most of the change was observed at three months after the surgery. Six percent of the patients had additional knee surgery within two years. There was no evidence of differences in clinical, functional, or quality-of-life measures between the randomized groups at two years. Conclusions: Patients have substantial improvement following total knee replacement. This is the first adequately powered randomized controlled trial, of which we are aware, in which the effects of metal backing, patellar resurfacing, and a mobile bearing were investigated. We found no evidence of an effect of these variants on the rate of early complications or on functional recovery up to two years after total knee replacement. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.NIHR Health Technology Assessment Programme (Project Number 95/10/01); Howmedica Osteonics; Zimmer; DePuy, a Johnson and Johnson company; Corin Medical; Smith and Nephew Healthcare. Biomet Merck; and Wright CremascoliPeer reviewe

Total or Partial Knee Arthroplasty Trial - TOPKAT : study protocol for a randomised controlled trial

Peer reviewedPublisher PD

ISSLS PRIZE IN BIOENGINEERING SCIENCE 2019: biomechanical changes in dynamic sagittal balance and lower limb compensatory strategies following realignment surgery in adult spinal deformity patients.

Study designA longitudinal cohort study.ObjectiveTo define a set of objective biomechanical metrics that are representative of adult spinal deformity (ASD) post-surgical outcomes and that may forecast post-surgical mechanical complications. Current outcomes for ASD surgical planning and post-surgical assessment are limited to static radiographic alignment and patient-reported questionnaires. Little is known about the compensatory biomechanical strategies for stabilizing sagittal balance during functional movements in ASD patients.MethodsWe collected in-clinic motion data from 15 ASD patients and 10 controls during an unassisted sit-to-stand (STS) functional maneuver. Joint motions were measured using noninvasive 3D depth mapping sensor technology. Mathematical methods were used to attain high-fidelity joint-position tracking for biomechanical modeling. This approach provided reliable measurements for biomechanical behaviors at the spine, hip, and knee. These included peak sagittal vertical axis (SVA) over the course of the STS, as well as forces and muscular moments at various joints. We compared changes in dynamic sagittal balance (DSB) metrics between pre- and post-surgery and then separately compared pre- and post-surgical data to controls.ResultsStandard radiographic and patient-reported outcomes significantly improved following realignment surgery. From the DSB biomechanical metrics, peak SVA and biomechanical loads and muscular forces on the lower lumbar spine significantly reduced following surgery (- 19 to - 30%, all p &lt; 0.05). In addition, as SVA improved, hip moments decreased (- 28 to - 65%, all p &lt; 0.05) and knee moments increased (+ 7 to + 28%, p &lt; 0.05), indicating changes in lower limb compensatory strategies. After surgery, DSB data approached values from the controls, with some post-surgical metrics becoming statistically equivalent to controls.ConclusionsLongitudinal changes in DSB following successful multi-level spinal realignment indicate reduced forces on the lower lumbar spine along with altered lower limb dynamics matching that of controls. Inadequate improvement in DSB may indicate increased risk of post-surgical mechanical failure. These slides can be retrieved under Electronic Supplementary Material

Patient Outcomes Following Hip and Knee Joint Replacement Surgery: Role of the Social and Physical Environment in Recovery

Osteoarthritis is a degenerative joint disease that affects over 27 million Americans (Centers for Disease Control & Prevention, 2014). Joint replacement surgery is often recommended for patients who do not respond to conventional medical treatment. Post-surgical rehabilitation, especially occupational therapy (OT), promotes recovery in patients with osteoarthritis. Occupational therapy intervention is aimed at improving one’s ability to function independently in various environments and complete basic tasks of everyday life, such as eating, bathing, shopping, driving, and preparing food. While such tasks may seem mundane for some, others faced with debilitating conditions struggle to complete them without assistance. For individuals with osteoarthritis, social and environmental factors, including the social environment, the physical home environment, and the physical community environment influence recovery from hip and knee joint replacement surgery. However, these factors are not always considered in OT intervention. This study examines the influence of these three factors among older adults age 50-80 years who have had a recent hip or joint knee replacement surgery. The purpose of this study is to understand the role of the social and physical environments during post-surgical rehabilitation

Cross-cultural and construct validity of the Animated Activity Questionnaire

International audienc