Role Of Ultrasonography In Evaluation Of Ankle Joint Pathologies In Patients With Rheumatoid Arthritis - A One Year Hospital Based Cross Sectional Study

Abstract

Background and objectives: Rheumatoid arthritis is one of the common type of inflammatory arthritis especially important among various musculoskeletal disorders. It affects the individuals between 20 to 40 years of age in their more productive years and leads to chronic disability due to pain and deformity. The prevalence is highly variable ranging between 0.3% to 1%. It is more prevalent among females and those living in developed countries. The term ‘rheumatoid arthritis’ was first introduced by Garrod more than 150 years ago in order to differentiate this condition from other disease conditions with similar manifestations such as gout and acute rheumatic arthritis. Rheumatoid arthritis is characterized as a chronic inflammatory condition where the etiology is not known. The peripheral joints are more commonly involved and the polyarthritis is symmetric The importance of early diagnosis of rheumatoid arthritis is paramount. Rheumatoid arthritis not only affects the joints, but also has systemic involvement. Diagnosis of rheumatoid arthritis is based on clinical and laboratory findings. Pain, boggy swelling of the small joints with morning stiffness are most commonly reported in rheumatoid arthritis. Rheumatoid factor is positive among those with rheumatoid arthritis, though it may not be specific. Anti-citrulinated protein antibody is more specific for RA. One of the more recently explored modalities for diagnosis of rheumatoid arthritis is ultrasound of the ankle. Patients presenting with ankle pain during the early stages are more likely to have isolated tenosynovitis of ankle joint. This feature of rheumatoid arthritis can be found even before the onset of deformities in the advanced stages of the disease. Although MRI is the gold standard for evaluating the ankle changes, it is more expensive and hence not applicable in wider settings. Ultrasound on the other hand, is cost-effective and can be used to screen patients presenting with ankle pain in the outpatient department. The objective of this study is to evaluate the role of Ultrasonography of Ankle Joint in confirmed cases of Rheumatoid Arthritis presenting with either clinical or subclinical ankle involvement. Materials and methods One year prospective cross sectional study was done in Department of Radio-diagnosis at the KLE’S Dr. Prabhakar Kore hospital & MRC, Belagavi. 30 patents were included in the study. These patients are subjected to sonourethrography of bilateral ankle joints. In this study, tibio talar joint synovits was considered as primary outcome variable and demographic parameters like age, gender etc were considered as primary explanatory variables. Results The most common muscle involved in the medial compartment was tibialis posterior. 33.3% of the subjects in the right ankle group had tenosynovitis of tibialis posterior compared to 26.67% in the left ankle group. The vascularity of tibialis posterior was abnormal in 30% of subjects in the right ankle group compared to 26.67% in the left group. The most common muscle involved in the lateral compartment was penoneus longus. In the lateral compartment, 30% had tenosynovitis of peroneus longus in the right ankle group compared to 23.33% in the left ankle group. The most common muscle involved in the anterior compartment was tibialis anterior. In the anterior compartment, 30 % had tenosynovitis of tibialis anterior in the right side group and 20% in the left group. Thickening of the synovium of talocalcaneal joint and increased vascularity were other parameters evaluated affecting 23.3% in the right side group compared to 13.33% in the left side group and 20% of subjects in the right side group and 10% in the left side group respectively. 16.67% had bulky and hypoechoic tendoachilles at insertion (Enthesitis) in the right sided group compared to 10% in the left sided group. Interpretation and conclusion Rheumatoid arthritis is a chronic inflammatory condition with systemic involvement. In our study majority (73.3%) of the study population were females and majority aged between 30 to 39 years. 80% of subjects were positive for RA factor. The most common muscle involved in the medial, lateral and anterior compartments were tibialis posterior, peroneus longus and tibialis anterior respectively. The common findings observed were tenosynovitis and increased vascularity in the tendons involved, presence of increased joint fluid, joint erosions and synovium thickening of talocalcaneal joint and retrocalcaneal region. In the medial compartment, 33.3% of the subjects in the right ankle group had tenosynovitis of tibialis posterior compared to 26.67% in the left ankle group. In the medial compartment, 20% had tenoynovitis of flexor digitorum longus in the right ankle group compared to 16.67% in the left ankle group. In the lateral compartment, 30% had tenosynovitis of peroneus longus in the right ankle group compared to 23.33% in the left ankle group. In the anterior compartment, 30% had tenosynovitis of tibialis anterior in the right side group and 20% in the left group. In Talocalcaneal joint, 23.3% had thickened synovium in the right side group compared to 13.33% in the left side group. Ultrasound of the ankle is a very efficient, simple, reliable and easily accessible modality distinguishing rheumatological pathologies of the ankle such as tenosynovitis, synovitis, and erosions. USG gives a wide range of information that can be used as complementary data to the clinical assessment. Early diagnosis of rheumatoid arthritis by USG will aid in early initiation of treatment and better quality of life.