L.M. Forsythe

A randomised trial of a brace for patellofemoral osteoarthritis targeting knee pain and bone marrow lesions

Objective Braces used to treat (PF) osteoarthritis (OA) may reduce contact stress across the PF joint. We hypothesised that in PF OA, braces would decrease knee pain and shrink PF bone marrow lesions (BMLs). Methods Eligible subjects had painful PF OA. Subjects were randomly allocated to brace or no brace for 6 weeks. Knee MRIs were acquired at baseline and 6 weeks. We measured BMLs on post-contrast fat suppressed sagittal and proton density weighted axial images. The primary symptom outcome was change in pain at 6 weeks during a preselected painful activity, and the primary structural outcome was BML volume change in the PF joint. Analyses used multiple linear regression. Results We randomised 126 subjects aged 40–70 years (mean age 55.5  years; 72 females (57.1%)). Mean nominated visual analogue scale (0–10 cm) pain score at baseline was 6.5 cm. 94 knees (75%) had PF BMLs at baseline. Subjects wore the brace for a mean of 7.4 h/day. 6 subjects withdrew during the trial. After accounting for baseline values, the brace group had lower knee pain than the control group at 6 weeks (difference between groups −1.3 cm, 95% CI −2.0 to −0.7; p<0.001) and reduced PF BML volume (difference −490.6 mm3, 95% CI −929.5 to −51.7; p=0.03) but not tibiofemoral volume (difference −53.9 mm3, 95% CI −625.9 to 518.2; p=0.85). Conclusions A PF brace reduces BML volume in the targeted compartment of the knee, and relieves knee pain. Trial registration number UK. ISRCTN50380458.

Ankle motion influences the external knee adduction moment and may predict who will respond to lateral wedge insoles? : an ancillary analysis from the SILK trial

Summary Objective Lateral wedge insoles are a potential simple treatment for medial knee osteoarthritis (OA) patients by reducing the external knee adduction moment (EKAM). However in some patients, an increase in their EKAM is seen. Understanding the role of the ankle joint complex in the response to lateral wedge insoles is critical in understanding and potentially identifying why some patients respond differently to lateral wedge insoles. Method Participants with medial tibiofemoral OA underwent gait analysis whilst walking in a control shoe and a lateral wedge insole. We evaluated if dynamic ankle joint complex coronal plane biomechanical measures could explain and identify those participants that increased (biomechanical non-responder) or decreased (biomechanical responder) EKAM under lateral wedge conditions compared to the control shoe. Results Of the 70 participants studied (43 male), 33% increased their EKAM and 67% decreased their EKAM. Overall, lateral wedge insoles shifted the centre of foot pressure laterally, increased eversion of the ankle/subtalar joint complex (STJ) and the eversion moment compared to the control condition. Ankle angle at peak EKAM and peak eversion ankle/STJ complex angle in the control condition predicted if individuals were likely to decrease EKAM under lateral wedge conditions. Conclusions Coronal plane ankle/STJ complex biomechanical measures play a key role in reducing EKAM when wearing lateral wedge insoles. These findings may assist in the identification of those individuals that could benefit more from wearing lateral wedge insoles.

A New Approach to Prevention of Knee Osteoarthritis: Reducing Medial Load in the Contralateral Knee

Objective. Few if any prevention strategies are available for knee osteoarthritis (OA). In those with symptomatic medial OA, the contralateral knee may be at high risk of disease, and a reduction in medial loading in that knee might prevent disease or its progression there. Our aim was to determine how often persons with medial OA on 1 side had either concurrent or later medial OA on the contralateral side, and whether an intervention known to reduce medial loading in affected knees with medial OA might reduce medial loading in the contralateral knee. Lateral wedge insoles reduce loading across an affected medial knee but their effect on the contralateral knee is unknown. Methods. To determine the proportion of persons with medial knee OA who had concurrent medial contralateral OA or developed contralateral medial OA later, we examined knee radiographs from the longitudinal Framingham Osteoarthritis Study. Then, to examine an approach to reducing medial load in the contralateral knee, 51 people from a separate study with painful medial tibiofemoral OA underwent gait analysis wearing bilateral controlled shoes with no insoles, and then with 2 types of wedge insoles laterally posted by 5°. Primary outcome was the external knee adduction moment (EKAM) in the contralateral knee. Nonparametric CI were constructed around the median differences in percentage change in the affected and contralateral sides. Results. Of Framingham subjects with medial radiograph knee OA, 137/152 (90%) either had concurrent contralateral medial OA or developed it within 10 years. Of those with medial symptomatic knee OA, 43/67 (64%) had or developed the same disease state in the contralateral knee. Compared to a control shoe, medial loading was reduced substantially on both the affected (median percentage EKAM change −4.84%; 95% CI −11.33% to −0.65%) and contralateral sides (median percentage EKAM change −9.34%; 95% CI −10.57% to −6.45%). Conclusion. In persons with medial OA, the contralateral knee is also at high risk of medial OA. Bilateral reduction in medial loading in knees by use of strategies such as lateral wedge insoles might not only reduce medial load in affected knees but prevent knee OA or its progression on the contralateral side.

The effect of different types of insoles or shoe modifications on medial loading of the knee in persons with medial knee osteoarthritis: a randomised trial

Many conservative treatments exist for medial knee osteoarthritis (OA) which aims to reduce the external knee adduction moment (EKAM). The objective of this study was to determine the difference between different shoes and lateral wedge insoles on EKAM, knee adduction angular impulse (KAAI), external knee flexion moment, pain, and comfort when walking in individuals with medial knee OA. Seventy individuals with medial knee OA underwent three‐dimensional walking gait analysis in five conditions (barefoot, control shoe, typical wedge, supported wedge, and mobility shoe) with pain and comfort recorded concurrently. The change in EKAM, KAAI, external knee flexion moment, pain, and comfort were assessed using multiple linear regressions and pairwise comparisons. Compared with the control shoe, lateral wedge insoles and barefoot walking significantly reduced early stance EKAM and KAAI. The mobility shoe showed no effect. A significant reduction in latter stance EKAM was seen in the lateral wedge insoles compared to the other conditions, with only the barefoot condition reducing the external knee flexion moment. However, the mobility shoe showed significant immediate knee pain reduction and improved comfort scores. Different lateral wedge insoles show comparable reductions in medial knee loading and in our study, the mobility shoe did not affect medial loading.

The relationship between reductions in knee loading and immediate pain response whilst wearing lateral wedged insoles in knee osteoarthritis.

Studies of lateral wedge insoles (LWIs) in medial knee osteoarthritis (OA) have shown reductions in the average external knee adduction moment (EKAM) but no lessening of knee pain. Some treated patients actually experience increases in the EKAM which could explain the overall absence of pain response. We examined whether, in patients with painful medial OA, reductions in the EKAM were associated with lessening of knee pain. Each patient underwent gait analysis whilst walking in a control shoe and two LWIs. We evaluated the relationship between change in EKAM and change in knee pain using Spearman Rank Correlation coefficients and tested whether dichotomizing patients into biomechanical responders (decreased EKAM) and non‐responders (increased EKAM) would identify those with reductions in knee pain. In 70 patients studied, the EKAM was reduced in both LWIs versus control shoe (−5.21% and −6.29% for typical and supported wedges, respectively). The change in EKAM using LWIs was not significantly associated with the direction of knee pain change. Further, 54% were biomechanical responders, but these persons did not have more knee pain reduction than non‐responders. Whilst LWIs reduce EKAM, there is no clearcut relationship between change in medial load when wearing LWIs and corresponding change in knee pain.

Sensitivity to Change of Patient-Preference Measures for Pain in Patients With Knee Osteoarthritis: Data From Two Trials.

In osteoarthritis (OA) clinical trials, a pain measure that is most sensitive to change is considered optimal. We compared sensitivity to change of patient‐reported pain outcomes, including a patient‐preference measure (where the patient nominates an activity that aggravates their pain).

Sensitivity to Change of Patient-Preference Measures for Pain in Trials of Patients with Knee Osteoarthritis: A Secondary Analysis from the BRACE and TASK Trials

In osteoarthritis (OA) clinical trials, a pain measure that is most sensitive to change is considered optimal. We compared sensitivity to change of patient‐reported pain outcomes, including a patient‐preference measure (where the patient nominates an activity that aggravates their pain).

Foot and ankle biomechanics play a role in biomechanical response to lateral wedge insoles

Lateral wedge insoles have consistently shown to reduce the external knee adduction moment (EKAM) in medial knee osteoarthritis (OA) patients; although there is evidence that certain patients have a paradoxical increase in EKAM. This may be a key factor in determining clinical response and thus identifying and understanding why these patients increase EKAM is critical for prescribing the correct treatment for these patients. Previous evidence has suggested that foot and ankle biomechanics play a role in reducing EKAM by shifting the centre of foot pressure (COFP) laterally and increasing the valgus orientation of the calcaneus, which shortens the lever arm in respect of the knee, thus reducing the EKAM. To date, patients have been studied irrespective of biomechanical response to lateral wedge insoles. In this study we investigated whether dynamic ankle biomechanics can assist in identifying and explaining why some patients increase EKAM and other decrease EKAM when wearing a lateral wedge.

383 WORMS BONE MARROW LESION SCORES AND SEGMENTATION YIELD SIMILAR FINDINGS

Purpose: Frontal plane malalignment is a known risk factor for development and progression of knee osteoarthritis (OA). In established disease, using standard MR imaging has shown that varus malalignment is associated with morphological changes like meniscal degeneration, bone attrition and cartilage loss. Using quantitative MRI, T1ø and T2 relaxation times have emerged as promising markers of early cartilage changes. The purpose of this study was to examine the association of frontal plane malalignment with cartilage composition using quantitative MR imaging. Methods: 38 subjects with knee OA were stratified into varus (n =12, age: 61.2±10.3y, BMI: 28.6±5.1kg/m2; axis: 174.5±4.6°), neutral (n = 19, age: 56.8±7.2y, BMI: 27.1±5.9kg/m2 axis: 179.9±1.2°) or valgus (n = 7, age: 57.1±12.2y, BMI: 25.9±4.5 kg/m2; axis: 183.8±2.1°) groups based on the anatomical alignment from weight-bearing flexed PA radiographs. MRI was done using a 3T GE Excite Signa MR Scanner. Sequences used were (i) high-resolution fat suppressed spoiled-gradient-echo (SPGR) (for cartilage thickness), (ii) T2-weighted fat-saturated FSE (for clinical WORMS grading) sagittal 3D (iii) T1ø and (iv) T2 maps. T1ø and T2 relaxation times were quantified for the medial and lateral tibial and femoral condyles. Medio-lateral (M/L) ratio of T1ø, T2 and thickness were calculated for tibia, femur. Pearson’s correlation was used to correlate alignment with T1ø and T2 relaxation times of individual compartments and M/L ratios in subjects from varus and neutral groups pooled together. One way ANOVA was used for differences in M/L ratios between the 3 groups. Results: Greater varus angle was associated with a higher M/L T1ø ratio at the tibia and higher M/L T2 ratio at the femur and tibia (Table 1).

Corrigendum to “Ankle motion influences the external knee adduction moment and may predict who will respond to lateral wedge insoles?: An ancillary analysis from the SILK trial” [Osteoarthr Cartil 23 (2015) 1316–1322]

y School of Health Sciences, University of Salford, Salford, UK z Arthritis Research UK Epidemiology Unit, Centre for Musculoskeletal Research, University of Manchester, Manchester, UK x NIHR Manchester Musculoskeletal Biomedical Research Unit (BRU), Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK k Clinical Epidemiology Unit, Boston University School of Medicine, Boston, MA, USA