Assessment of the natural history of forefoot bursae using ultrasonography in patients with rheumatoid arthritis: a twelve-month investigation.

OBJECTIVE: To determine the natural history and clinical significance of forefoot bursae over a 12-month period in patients with rheumatoid arthritis (RA). METHODS: Patients with RA (n=149) attending rheumatology outpatient clinics were assessed at baseline. A total of 120 participants, mean±SD age 60.7±12.1 years and mean±SD disease duration 12.99±10.4 years, completed the 12-month followup (98 women, 22 men, 93 rheumatoid factor positive, 24 rheumatoid factor negative, and 3 unknown). Musculoskeletal ultrasound (US) was used to identify forefoot bursae in all of the participants. Clinical markers of disease activity (well-being visual analog scale [VAS], erythrocyte sedimentation rate [ESR], C-reactive protein [CRP] level, and Disease Activity Score in 28 joints [DAS28]) and foot symptoms on the Leeds Foot Impact Scale (LFIS) Questionnaire were recorded on both occasions. RESULTS: Presence of US-detectable forefoot bursae was identified in 93.3% of returnee (n=120) participants (individual mean 3.7, range 0-11) at baseline. Significant associations were identified between bursae presence and patient-reported foot impact for impairment/footwear (LFISIF ; baseline: r=0.226, P=0.013 and 12 months: r=0.236, P=0.009) and activity limitation/participation restriction (LFISAP; baseline: r=0.254, P=0.005 and 12 months: r=0.235, P=0.010). After 12 months, 42.5% of participants had an increase in the number of US-detectable forefoot bursae and 45% of participants had a decrease. Changes in bursae number significantly correlated with changes in LFISIF (r=0.216, P=0.018) and LFISAP (r=0.193, P=0.036). No significant associations were identified between changes in bursae and changes in global well-being VAS, ESR, CRP level, or DAS28. CONCLUSION: The findings of this study suggest that forefoot bursae may regress or hypertrophy over time in patients with RA, and that these changes may be associated with self-reported foot impairment and activity restriction.

Improvement in symptoms and signs in the forefoot of patients with rheumatoid arthritis treated with anti-TNF therapy.

BACKGROUND: Inhibition of tumour necrosis factor (TNF) is an effective way of reducing synovitis and preventing joint damage in rheumatoid arthritis (RA), yet very little is known about its specific effect on foot pain and disability. The aim of this study was to evaluate whether anti-TNF therapy alters the presence of forefoot pathology and/or reduces foot pain and disability. METHODS: Consecutive RA patients starting anti-TNF therapy (infliximab, etanercept, adalimumab) were assessed for presence of synovial hypertrophy and synovitis in the 2nd and 5th metatarso-phalangeal (MTP) joints and plantar forefoot bursal hypertrophy before and 12 weeks after therapy. Tender MTP joints and swollen bursae were established clinically by an experienced podiatrist and ultrasound (US) images were acquired and interpreted by a radiologist. Assessment of patient reported disease impact on the foot was performed using the Manchester Foot Pain and Disability Index (MFPDI). RESULTS: 31 patients (24 female, 7 male) with RA (12 seronegative, 19 seropositive) completed the study: mean age 59.6 (SD 10.1) years, disease duration 11.1 (SD 10.5) years, and previous number of Disease Modifying Anti Rheumatic Drugs 3.0 (1.6). Significant differences after therapy were found for Erythrocyte Sedimentation Rate (t = 4.014, p < 0.001), C-reactive protein (t = 3.889, p = 0.001), 28 joint Disease Activity Score (t = 3.712, p = 0.0001), Visual Analog Scale (t = 2.735, p = 0.011) and Manchester Foot Pain and Disability Index (t = 3.712, p = 0.001).Presence of MTP joint synovial hypertrophy on US was noted in 67.5% of joints at baseline and 54.8% of joints at twelve weeks. Presence of plantar forefoot bursal hypertrophy on US was noted in 83.3% of feet at baseline and 75% at twelve weeks. Although there was a trend for reduction in observed presence of person specific forefoot pathology, when the frequencies were analysed (McNemar) this was not significant. CONCLUSIONS: Significant improvements were seen in patient reported foot pain and disability 12 weeks after commencing TNF inhibition in RA, but this may not be enough time to detect changes in forefoot pathology.

A novel approach to mechanical prophylaxis: calf impulse technology mimics natural ambulation more effectively than sequential calf compression.

BACKGROUND: The risk of thrombosis can be reduced by mechanical compression, but the optimal device is unknown. OBJECTIVES: To record the effect of natural ambulation on deep venous flow, providing a reference for evaluating the efficacy of mechanical compression systems, assuming that ambulation is the gold standard against which such systems should be compared; and to compare the hemodynamic effect of the A-V Impulse System CalfPad garment (A-VI) (Orthofix Vascular Novamedix, United Kingdom) with the SCD Express calf compression garment (SCD) (Covidien, USA). METHODS: Twelve healthy volunteers were recruited and randomly assigned to either A-VI or SCD in a two-device, two-period crossover design. Peak femoral velocity (PFV) was calculated using custom ultrasound software and compared with baseline values. Ultrasound images were recorded. RESULTS: A-VI augmented the mean (± SD) PFV to 59.79±29.07 cm/s compared with 22.86±5.73 cm/s for SCD. The actual percentage increase from baseline was approximately five times greater for A-VI (mean increase 385%±260%) than SCD (mean increase 81%±53%). Using an analysis of covariance model, with baseline fitted as a covariate, a highly statistically significant difference in favour of A-VI was detected (P=0.0002). Least square (adjusted) means (±95% CIs) were 37.24 cm/s (21.39 cm/s to 64.84 cm/s) for A-VI and 6.71 cm/s (3.86 cm/s to 11.69 cm/s) for SCD, representing more than fivefold greater improvement in PFV from rest with the A-VI device than with the SCD device. CONCLUSION: Pulsatile impulse calf compression (A-VI) more closely mimics PFV of normal ambulation than slow-squeeze sequential compression (SCD). Pulsatile calf compression may provide superior protection against thrombosis in immobile patients.

Musculoskeletal ultrasound imaging of the plantar forefoot in patients with rheumatoid arthritis: inter-observer agreement between a podiatrist and a radiologist.

BACKGROUND: The use of musculoskeletal ultrasound (MSUS) in the diagnosis and management of foot and ankle musculoskeletal pathology is increasing. Due to the wide use of MSUS and the depth and breadth of training required new proposals advocate tailored learning of the technique to discrete fields of practice. The aims of the study were to evaluate the inter-observer agreement between a MSUS radiologist and a podiatrist, who had completed basic skills training in MSUS, in the MSUS assessment of the forefoot of patients with Rheumatoid Arthritis. METHODS: A consecutive sample of thirty-two patients with rheumatoid arthritis was assessed for presence of synovitis, erosions and bursitis within the forefoot using MSUS. All MSUS assessments were performed independently on the same day by a podiatrist and one of two Consultant Radiologists experienced in MSUS. RESULTS: Moderate agreement on image acquisition and interpretation was achieved for bursitis (kappa 0.522; p < 0.01) and erosions (kappa 0.636; p < 0.01) and fair agreement for synovitis (kappa 0.216; p < 0.05) during the primary assessments. Following a further training session, substantial agreement (kappa 0.702) between the two investigators was recorded. The sensitivity of the podiatrist using MSUS was 82.4% for detection of bursitis, 83.0% for detection of erosion and 84.0% for detection of synovitis. Specificity of the podiatrist using MSUS was 88.9% for detection of bursitis, 80.7% for detection of erosion and 35.9% for detection of synovitis. CONCLUSION: This study demonstrated good inter-observer agreement between a podiatrist and radiologist on MSUS assessment of the forefoot, particularly for bursitis and erosions, in patients with rheumatoid arthritis. There is scope to further evaluate and consider the role of podiatrists in the MSUS imaging of the foot following appropriate training and also in the development of reliable protocols for MSUS assessment of the foot.