What can hand sonography and nerve conduction velocity disclose regarding hand dysfunction in rheumatoid arthritis patients?

BACKGROUND

Hand function in rheumatoid arthritis (RA) is a major determinant of functional ability.

OBJECTIVE

To explore hand dysfunction in RA patients and to investigate the role of ultrasonography and nerve conduction studies in detecting factors affecting hand dysfunction.

PATIENTS AND METHODS

One hundred RA patients were included in this cross-sectional study and subgrouped into those with a weak hand grip (group A) and those with a good hand grip (group B). Ultrasonographic examinations and nerve conduction studies were performed. Multiple regression analysis and receiver operating characteristic curves were used.

RESULTS

The age of enrolled patients was 45.16 ± 11.66 years, 88% were females. Patients in group A had poorer hand function and quality of life compared to those in group B (P < 0.001). Using musculoskeletal ultrasonography (MSUS), higher scores of synovial proliferation, bone erosion, and cartilage damage were found in group A. Hands with weak grip strength had reduced sensory median and ulnar conduction velocity than those with good grip (P = 0.02 and 0.01, respectively). The grip strength test had 92% sensitivity and 95% specificity for prediction of hand dysfunction, while upon combining synovial proliferation with ulnar nerve sensory latency and the grip strength test, the greatest sensitivity (98%) was reached with 55% specificity.

CONCLUSION

Median and ulnar sensory conduction changes together with signs of chronic inflammation and joint destruction in MSUS are prevalent in patients with poor hand grip. Combined grip strength, ulnar nerve sensory conduction study, and synovial proliferation could represent a sensitive predictor of hand dysfunction in RA.