The relation between upper extremity joint involvement and grip force in early rheumatoid arthritis: a retrospective study

The relation between synovitis of individual finger joints and grip force over the first 5 years in early rheumatoid arthritis - a cohort study

OBJECTIVE

The objective of this study was to investigate the relation between swelling and tenderness of individual finger joints and grip force in patients with early rheumatoid arthritis (RA).

METHODS

In an inception cohort of patients with early RA (symptom duration < 12 months), all patients were examined by the same rheumatologist, and grip force was measured using the Grippit instrument at inclusion, 1 and 5 years. The average grip force values of each hand were evaluated and expressed as % of expected values, based on age- and sex-specific reference values. Linear regression analyses were used to assess the cross-sectional relation between the involvement of individual finger joints and grip force. In generalized estimating equations, the impact of time-varying synovitis/tenderness on grip force over time was estimated. Analyses were adjusted for wrist involvement, erythrocyte sedimentation rate, and patient-reported pain.

RESULTS

In 215 patients with early RA, grip force was 39% of expected at diagnosis, and increased to 56% after 5 years. Synovitis of the first metacarpophalangeal (MCP) joint (60% and 69% at baseline in the right and left hand) was associated with reduced grip force at inclusion (adjusted ß - 9.2 percentage unit of expected grip force; 95% CI - 13.6 to - 4.8 for both hands combined) and at all follow-up evaluations. Synovitis of MCP I and MCP IV (12% at baseline) was significantly associated with reduced grip force over time in both hands. Proximal interphalangeal (PIP) joint swelling, and tenderness of MCP or PIP joints, had less impact on grip force.

CONCLUSION

MCP I synovitis is the major contributor to reduced grip force in patients with early RA. This underlines the importance of the involvement of the thumb for impaired hand function in RA. MCP IV synovitis, but not PIP involvement or finger joint tenderness, also has a substantial impact on grip force.

Outcomes of Pyrocarbon Arthroplasty in Metacarpophalangeal Joints Affected by Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) affecting the metacarpophalangeal (MCP) joint may warrant arthroplasty. The purpose of this study was to investigate implant survivorship, complications, radiographic outcomes, and clinical outcomes in patients undergoing MCP arthroplasty with a pyrocarbon implant to treat RA.

METHODS

In all, 124 MCP joint pyrocarbon arthroplasties in 40 patients performed to treat RA were reviewed. Operations were at the index (n = 43, 35%), middle (n = 33, 27%), ring (n = 27, 22%), and small (n = 21, 17%) fingers from 1998 to 2009 in 105 (85%) female and 19 (15%) male joints with a mean age of 54 ± 11 years. Mean postoperative follow-up was 6 ± 3 years. All patients achieved at least 2 years of follow-up.

RESULTS

Rates of implant survivorship at 1, 2, 5, and 10 years were 98%, 98%, 90%, and 81%, respectively. Fifteen percent (n = 18) of arthroplasties underwent revision at a mean 5 ± 3 years postoperatively. The overall reoperation rate was 29% (n = 36). Rates of survival from reoperation at 1, 2, 5, and 10 years were 85%, 84%, 76%, and 68%, respectively. Complications occurred in 32% (n = 40). Pain ratings improved postoperatively (P < .01). Arc of motion improved from 37 ± 21 to 43 ± 19 (P = .03). Both appositional and oppositional strength improved after surgery; however, there was no improvement in grip strength (P < .01).

CONCLUSIONS

Metacarpophalangeal arthroplasty with a pyrocarbon implant demonstrated reliable improvement in pain and arc of motion in patients with RA. Complication and overall reoperation rates were high, while 1 in 10 undergo revision within 5 years postoperatively.

Systemic lupus erythematosus: a systematic review with meta-analysis on muscle strength, muscle mass, and physical function

To perform a systematic review with meta-analysis to verify muscle strength, muscle mass, and physical function of patients with systemic lupus erythematosus (SLE) and compare then with healthy individuals and patients with rheumatoid arthritis (RA). A systematic review with meta-analysis of observational studies published in English up to 2022 was performed using MEDLINE (via PubMed) and other relevant sources. Search strategies were based on pre-defined keywords and medical subject headings. The methodological quality of the studies was assessed using the Newcastle-Ottawa Scale. Mean difference (MD) or standardized mean difference (SMD) and 95% confidence intervals (CI) were combined using a random-effects model. Sensitivity analyses were performed when necessary. The significance level was set at p < 0.05. The systematic review included 19 studies and the meta-analysis included 11 studies. SLE patients appear to have less muscle strength assessed by handgrip than healthy controls (SLE = 21.74 kg; healthy controls = 29.34 kg; p < 0.05). SLE patients seem to have greater strength than patients with RA, but this difference was not statistically significant (RA = 17.24 kg; p = 0.210). However, in the sensitivity analysis, SLE group without deforming arthropathy showed higher muscle strength than the RA (p = 0.0001). SLE patients with deforming arthropathy have lower muscle strength compared to SLE patients without deforming arthropathy (p < 0.01). Muscle mass was similar in SLE patients compared to the RA group and healthy controls (p > 0.05). However, RA patients have a higher BMI than the two groups (p < 0.05). Patients with SLE have regular physical function. Muscle strength is affected in SLE patients. SLE patients with deforming arthropathy have less muscle strength than patients without deforming arthropathies.