Impairment-targeted exercises for older adults with knee pain: a proof-of-principle study (TargET-Knee-Pain).

BACKGROUND: Therapeutic exercise is an effective intervention for knee pain and osteoarthritis (OA) and should be individualised. In a preliminary, proof-of-principle study we sought to develop a home exercise programme targeted at specific physical impairments of weak quadriceps, reduced knee flexion range of motion (ROM) and poor balance, and evaluate whether receipt of this was associated with improvements in those impairments and in patient-reported outcomes among older adults with knee pain. METHODS: This community-based study used a single group, before-after study design with 12-week follow-up. Participants were 58 adults aged over 56 years with knee pain and evidence of quadriceps weakness, loss of flexion ROM, or poor balance, recruited from an existing population-based, observational cohort. Participants received a 12-week home exercise programme, tailored to their physical impairments. The programme was led, monitored and progressed by a physiotherapist over six home visits, alternating with six telephone calls. Primary outcome measures were maximal isometric quadriceps strength, knee flexion ROM and timed single-leg standing balance, measured at baseline, 6 and 12 weeks by a research nurse blinded to the nature and content of participants' exercise programmes. Secondary outcome measures included the WOMAC. RESULTS: At 12 weeks, participants receiving strengthening exercises demonstrated a statistically significant change in quadriceps isometric strength compared to participants not receiving strengthening exercises: 3.9 KgF (95 % CI 0.1, 7.8). Changes in knee flexion ROM (2.1° (-2.3, 6.5)) and single-leg balance time (-2.4 s (-4.5, 6.7)) after stretching and balance retraining exercises respectively, were not found to be statistically significant. There were significant improvements in mean WOMAC Pain and Physical Function scores: -2.2 (-3.1, -1.2) and -5.1 (-7.8, -2.5). CONCLUSIONS: A 12-week impairment-targeted, home-based exercise programme for symptomatic knee OA appeared to be associated with modest improvements in self-reported pain and function but no strong evidence of greater improvement in the specific impairments targeted by each exercise package, with the possible exception of quadriceps strengthening. TRIAL REGISTRATION: Clinical Trial Registration Number: ISRCTN 61638364 Date of registration: 24 June 2010.

Clinical features of symptomatic patellofemoral joint osteoarthritis.

INTRODUCTION: Patellofemoral joint osteoarthritis (OA) is common and leads to pain and disability. However, current classification criteria do not distinguish between patellofemoral and tibiofemoral joint OA. The objective of this study was to provide empirical evidence of the clinical features of patellofemoral joint OA (PFJOA) and to explore the potential for making a confident clinical diagnosis in the community setting. METHODS: This was a population-based cross-sectional study of 745 adults aged ≥ 50 years with knee pain. Information on risk factors and clinical signs and symptoms was gathered by a self-complete questionnaire, and standardised clinical interview and examination. Three radiographic views of the knee were obtained (weight-bearing semi-flexed posteroanterior, supine skyline and lateral) and individuals were classified into four subsets (no radiographic OA, isolated PFJOA, isolated tibiofemoral joint OA, combined patellofemoral/tibiofemoral joint OA) according to two different cut-offs: 'any OA' and 'moderate to severe OA'. A series of binary logistic and multinomial regression functions were performed to compare the clinical features of each subset and their ability in combination to discriminate PFJOA from other subsets. RESULTS: Distinctive clinical features of moderate to severe isolated PFJOA included a history of dramatic swelling, valgus deformity, markedly reduced quadriceps strength, and pain on patellofemoral joint compression. Mild isolated PFJOA was barely distinguished from no radiographic OA (AUC 0.71, 95% CI 0.66, 0.76) with only difficulty descending stairs and coarse crepitus marginally informative over age, sex and body mass index. Other cardinal signs of knee OA - the presence of effusion, bony enlargement, reduced flexion range of movement, mediolateral instability and varus deformity - were indicators of tibiofemoral joint OA. CONCLUSIONS: Early isolated PFJOA is clinically manifest in symptoms and self-reported functional limitation but has fewer clear clinical signs. More advanced disease is indicated by a small number of simple-to-assess signs and the relative absence of classic signs of knee OA, which are predominantly manifestations of tibiofemoral joint OA. Confident diagnosis of even more advanced PFJOA may be limited in the community setting.

Impairment-targeted exercises for older adults with knee pain: protocol for a proof-of-principle study.

BACKGROUND: Exercise therapy for knee pain and osteoarthritis remains a key element of conservative treatment, recommended in clinical guidelines. Yet systematic reviews point to only modest benefits from exercise interventions.One reason for this might be that clinical trials tend to use a one-size-fits-all approach to exercise, effectively disregarding the details of their participants' clinical presentations. This uncontrolled before-after study (TargET-Knee-Pain) aims to test the principle that exercises targeted at the specific physical impairments of older adults with knee pain may be able to significantly improve those impairments. It is a first step towards testing the effectiveness of this more individually-tailored approach. METHODS/DESIGN: We aim to recruit 60 participants from an existing observational cohort of community-dwelling older adults with knee pain. Participants will all have at least one of the three physical impairments of weak quadriceps, a reduced range of knee flexion and poor standing balance. Each participant will be asked to undertake a programme of exercises, targeted at their particular combination and degree of impairment(s), over the course of twelve weeks. The exercises will be taught and progressed by an experienced physiotherapist, with reference to a "menu" of agreed exercises for each of the impairments, over the course of six fortnightly home visits, alternating with six fortnightly telephone calls. Primary outcome measures will be isometric quadriceps strength, knee flexion range of motion, timed single-leg standing balance and the "Four Balance Test Scale" at 12 weeks. Key secondary outcome measures will be self-reported levels of pain, stiffness and difficulties with day-to-day functional tasks (WOMAC). Outcome measures will be taken at three time-points (baseline, six weeks and twelve weeks) by a study nurse blinded to the exercise status of the participants. DISCUSSION: This study (TargET-Knee-Pain) is the first step towards exploring whether an impairment-targeted approach to exercise prescription for older adults with knee pain may have sufficient efficacy to warrant further testing. If warranted, future randomised clinical trials may compare this approach with more traditional one-size-fits-all exercise approaches. TRIAL REGISTRATION: Current Controlled Trials ISRCTN61638364.