SLR - September 2009 - Kevin Murphy
Reference:
Sheane, B., Beddy, P., O’Connor, M., Miller, S., Cunnane, G. (2009). Targeted Ultrasound of the Fifth Metatarsophalangeal Joint in an Early Inflammatory Arthritis Cohort. Arthritis & Rheumatism (Arthritis Care & Research). 61( 7): 1004-1008.
Scientific Literature Review
Reviewed by: Kevin Murphy, DPM
Residency Program: Saint Vincent Hospital/Worcester Medical Center
Podiatric Relevance:
This paper discusses a method for early diagnosis of inflammatory arthritis utilizing ultrasound to visualize erosion about the 5th MTPJ.
Methods:
Thirty patients took part in the study. Seventeen already had the diagnosis of rheumatoid arthritis (RA). The remaining thirteen had undifferentiated arthritis (UA). Inflammatory arthritis was defined as morning joint stiffness lasting > 30 minutes and associated with joint pain, swelling and synovitis in at least one joint on clinical exam. RA was diagnosed according to the American College of Rheumatology criterion.
Each patient underwent lab testing, as well as radiographic and ultrasound imaging of both feet. The radiographs were read by a group of radiologists that did not perform the US. Each scan was performed by the same radiologist who was blinded to the radiographic results and underlying rheumatic diagnosis. US imaging was performed on a Philips HDI 5000 scanner using high frequency linear hockey stick transducers. The hand/foot musculoskeletal setting was used. Three views (dorsal, lateral and plantar) of the MTPJ were taken on each foot. Time of US was also recorded. A semi-quantitative scoring system and definitions of US abnormalities originally outlined by Szkudlarek were applied in this study. Age, sex, symptom duration, ESR, CRP, RF, anti-CCP, DAS28 and HAQ, duration of DMARD’s and corticosteroid exposure were all recorded at baseline. Informed consent was obtained. Data was analyzed using SPSS statistical software.
Results:
Twenty-two patients (73%) had articular abnormalities detected by US. Mean time of US for both MTPJs was 10.9 +/- 4.4 minutes. Ten patients had erosions on US despite an absence on radiograph. All seven patients that demonstrated erosions on radiograph also had abnormalities on US (P= 0.04). US also showed erosions in 46% of the UA cohort that were not seen on radiograph.
Conclusions:
Results of this study show that US of the 5th MTPJ can detect early joint damage in patient with RA. This can hopefully be used for early therapeutic decision making. More longitudinal studies with larger patient cohorts would be helpful.