A THREE YEAR RETROSPECTIVE SURVEY OF FOOT AND ANKLE ULTRASOUND INVESTIGATIONS UNDERTAKEN IN A RHEUMATOLOGY OUT-PATIENT CLINIC

Background: Musculoskeletal ultrasound (MSUS) is an accurate and sensitive technique to diagnose joint and soft tissue abnormalities in the foot and ankle [1,2]. It also improves the accuracy and subsequent clinical outcome for local corticosteroid injections [2].Objectives: To survey use and outcome of foot and ankle MSUS investigations undertaken in a rheumatology out-patient clinic.Methods: A 36 month retrospective review of consecutive foot and ankle MSUS reports from the rheumatology MSUS clinic Glasgow Royal Infirmary recording: 1) disease diagnosis, 2) referral indication for MSUS, 3) regions scanned, 4) MSUS outcomes, 5) MSUS aided interventions.Results: A total of 137 patients (90 female, 47 male) with a mean age of 49.9 years (SD 13.3) were referred for foot and ankle MSUS investigations. 69% had inflammatory joint disease, 12% unspecified diagnoses, 6% gout, 5% osteoarthritis, 8% other (connective tissue disease, benign hypermobility syndrome, tendon rupture, neuroma and plantar faciitis). A total 287 regions were scanned in the ankle, (32%), Achilles tendon (18%), plantar fascia (16%) forefoot (12%), lateral ankle (8%), talo-navicular joint (7%) medial ankle (4%) and tarsal joints (3%). Of the 287 scans taken, 53% were found to be abnormal. MSUS features identified included synovitis/tenosynovitis (25%), synovial/tendon thickening (17%), osteophyte formation (17%), erosions (12%), effusions (12%), tendon rupture/tear (6%), bony spur formation (3%), tendon calcification (3%), bursitis (3%), neuroma (1%) and nodule (1%). Following MSUS investigations changes in medication were initiated in 7 patients, and further imaging requested in 5 patients (3 MRI scans, 1 bone scan, 1 X-Ray). A total of 22 MSUS guided injections were undertaken in 21 patients at the following sites, 11 at the ankle joint, 4 at the plantar fascia, 4 at the peroneal tendons, 1 into the talo-navicular joint, 1 into retro-calcaneal bursa, and 1 into the metatarsal phalangeal joint.Conclusion: In a 36 month period, 137 patients were referred for MSUS investigation of the foot/ankle. It is surprising to note that 53% of scans showed an abnormality and that a significant proportion of these were unknown to the referring clinician. 15% of patients had a local steroid injection following MSUS investigation. MSUS of the foot and ankle is helpful in identifying sub-clinical pathology and facilitating steroid injection therapy.References: 1- Wakefield et al. 2003. Clinical & Experimental Rheumatology 21 (5 Suppl 31):S42-9. 2- D'Agostino et al. 2005. Arthritis & Rheumatism (Arthritis Care & Research), 15: 284-92.Citation: Ann Rheum Dis, volume 67, supplement II, year 2008, page 666Session: Miscellaneous forms of clinical care