Elbow joint involvement in rheumatoid arthritis patients: Clinical and ultrasound findings of the neglected joint

Abstract

Aim

of the work.

To assess the role of musculoskeletal ultrasound (MSUS) in the evaluation of elbow joint abnormalities in rheumatoid arthritis (RA) patients.

Patients and methods

This study was conducted on 47 RA patients subjected to clinical assessment and MSUS of both elbows.

Results

The mean age of the patients was 44 ± 9.55 years, they were 42 females, and 5 males and rheumatoid factor was positive in 76.6 %. This work was conducted on 94 elbow joints (59.6 % asymptomatic, 8.5 % unilateral, and 31.9 % bilateral joint pain). Ultrasound (US) abnormalities were present in 61 (64.9 %) of scanned joints. Effusion/synovial hypertrophy was the most common abnormality (31.9 %), followed by structural abnormalities at the common extensor tendon (26.6 %). There was a significant difference between symptomatic and asymptomatic elbow joints regarding US abnormalities of the elbows. MSUS showed high sensitivity and specificity in detection of elbow pathology compared to physical examination as the following: biceps tendon pathology (98.81 % specificity, 40 % sensitivity), effusion/synovial hypertrophy (62.32 % specificity, 68 % sensitivity), lateral epicondylitis (71.43 % specificity, 76.47 % sensitivity), medial epicondylitis (71.95 % specificity, 66.67 % sensitivity), and triceps enthesopathy (73.33 % specificity, 50 % sensitivity). Moderate agreement was observed for biceps tendon pathology (κ = 0.5, p < 0.001). Fair agreement was noted for effusion/synovial hypertrophy (κ = 0.25, p = 0.009). Similarly, fair agreement was observed for lateral epicondylitis (κ = 0.34, p < 0.001) and medial epicondylitis (κ = 0.23, p = 0.008). Although triceps enthesopathy showed only slight to no agreement between clinical examination and US (κ = 0.06, p = 0.31).

Conclusion

Elbow problems are frequent among individuals with RA, even in those who do not exhibit overt elbow symptoms.