Self-reported painful joint count and assessor-reported tender joint count as instruments to assess pain in hand osteoarthritis.

OBJECTIVES: To evaluate self-reported and assessor-reported joint counts for pain and their value in measuring pain and joint activity in hand OA patients. METHODS: A total of 524 patients marked painful joints on hand diagrams. Nurses assessed tenderness upon palpation. Pain was measured with a visual analogue scale pain and the Australian/Canadian hand OA index subscale pain. Synovitis and bone marrow lesions in right hand distal/proximal interphalangeal joints on MRI served as measure of joint activity. Agreement was assessed on the patient (intraclass correlation coefficient, Bland-Altman plot) and joint level (percentage absolute agreement). Correlations with measures of pain and joint activity were analysed, and joint level associations with synovitis/bone marrow lesions were calculated. RESULTS: Self-reported painful joint count (median 8, interquartile range 4-13) was consistently higher than assessor-reported tender joint count (3, 1-7). Agreement between patients and nurses on overall scores was low. Percentage absolute agreement on the joint level was 61-89%. Joint counts correlated similarly but weakly with measures of pain and joint activity (r = 0.14-0.38). On the joint level, assessor-reported tenderness was more strongly associated with synovitis/bone marrow lesions than self-reported pain. CONCLUSION: In hand OA, self- and assessor-reported joint counts cannot be used interchangeably, and measure other pain aspects than questionnaires. Assessor-reported tenderness was most closely related to MRI-defined joint activity.

Patients with clinically diagnosed hand OA not fulfilling the ACR classification criteria are in an earlier disease phase and more often have thumb base OA.

Objective: To investigate the performance of the American College of Rheumatology (ACR) classification criteria for hand osteoarthritis. Design: Longitudinal data up to four years from a cohort of consecutive patients with primary hand osteoarthritis diagnosed by their rheumatologist (Hostas study) were used to classify presence or absence of hand osteoarthritis according to the 1990 ACR criteria (traditional format: one major and 4 minor ACR criteria) (ACR+/ACR-). Demographics, Australian/Canadian osteoarthritis hand index (AUSCAN) pain and function were obtained. Hand radiographs were scored according to Kellgren-Lawrence; radiographic osteoarthritis was defined as Kellgren-Lawrence ≥2 in ≥1 CMC1 joint or ≥2 DIP/PIP/MCP joints. Results: Of 538 patients (mean age 61 years, 86.1% women) 485 (90.1%) fulfilled ACR criteria at baseline. Except for the minor criterion swelling of <3 MCP joints, all criteria differed between the groups. ACR- patients were younger, with higher BMI, a shorter time since diagnosis, and less bony enlargements, joint deformities and radiographic osteoarthritis, except for radiographic CMC1 osteoarthritis which was seen more often in ACR- patients. No difference in AUSCAN pain or function was seen between ACR- versus ACR+ patients. After follow-up 37/53 (69.8%) converted to ACR+, 2/53 (3.8%) did not, and 14/53 (26.4%) were lost to follow-up. Conclusions: In clinical practice the majority of patients fulfill the ACR classification criteria, but those in an earlier disease phase, with less signs of hand osteoarthritis or with primarily thumb base osteoarthritis are less likely to fulfill them. New classification criteria also including earlier disease stages and with attention for hand osteoarthritis subtypes are required.

Two-Year Changes in Magnetic Resonance Imaging Features and Pain in Thumb Base Osteoarthritis.

OBJECTIVE: To investigate the two-year course of pain and osteoarthritic features on magnetic resonance imaging (MRI) in the thumb base. METHODS: Patients in the Hand Osteoarthritis in Secondary Care (HOSTAS) cohort who had received radiographic examination, MRI, and clinical examination of the right thumb base at baseline and who had a 2-year follow-up period were studied. Pain on palpation of the thumb base was assessed on a 0-3 scale. MRIs were analyzed with the Outcome Measures in Rheumatology (OMERACT) thumb base osteoarthritis MRI scoring system for synovitis, bone marrow lesions (BMLs), subchondral bone defects, cartilage space loss, osteophytes, and subluxation. Radiographs were assessed for osteophytes and joint space narrowing. We studied the associations of changes in synovitis and BMLs with changes in pain using a logistic regression model adjusted for radiographic damage, with values expressed as odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Of 165 patients, 83% were women and the mean age was 60.7 years. At baseline, 65 patients had thumb base pain. At 2-year follow-up, pain had decreased in 32 patients and increased in 33 patients. MRI features remained stable in most patients. Structural MRI features generally deteriorated, while synovitis and BMLs improved in some individuals and deteriorated in others. Change in radiographic osteophytes rarely occurred (n = 10). Increased synovitis (odds ratio [OR] 3.4 [95% CI 1.3-9.3]) and increased BMLs (OR 5.1 [95% CI 2.1-12.6]) were associated with increased pain. Decreased BMLs appeared to be associated with decreased pain (OR 2.7 [95% CI 0.8-8.9]), and reductions in synovitis occurred too infrequently to calculate associations. CONCLUSION: Over 2 years, thumb base pain fluctuated, while MRI features changed in a minority of patients with hand osteoarthritis. Changes in synovitis and BMLs were associated with changes in pain on palpation, even after adjustment for radiographic damage.

Presence of Autoantibodies in Erosive Hand Osteoarthritis and Association with Clinical Presentation.

OBJECTIVE: To investigate whether 3 rheumatoid arthritis-associated antibodies [rheumatoid factor (RF) and anticitrullinated protein antibodies (ACPA) or anticarbamylated protein (anti-CarP) antibodies] are present in hand osteoarthritis (HOA) and associate with erosive OA (EOA). METHODS: Anti-CarP IgG was measured by ELISA in baseline sera of patients with HOA from 3 cohorts: HOSTAS (n = 510, 27.2% EOA), ECHO (n = 47), and EHOA (n = 23), and in sera of healthy controls (HC; n = 196, mean age 44.1 yrs, 51.0% women). Moreover, ACPA-IgG and RF-IgM were additionally determined in HOSTAS and HC. The prevalence of autoantibodies was compared between HOA and HC and between erosive and nonerosive HOA. In HOSTAS, hand radiographs were scored (Kellgren-Lawrence, Osteoarthritis Research Society International osteophyte and joint space narrowing) and C-reactive protein (CRP) levels, representing inflammation, were assessed. Groups were compared using nonparametric tests. RESULTS: The prevalence of anti-CarP was low and not significantly different between the total HOA group and HC (6.6% vs 3.6%, p = 0.12). In HOSTAS, the prevalence of all tested autoantibodies was low (anti-CarP 7.1%, ACPA 0.8%, RF 6.1%), and there were no significant differences observed between HOA patients and HC or between erosive and nonerosive HOA. Further, radiographic damage and CRP levels were similar in anti-CarP+ and anti-CarP-, and RF+ and RF- HOSTAS patients. CONCLUSION: The prevalence of autoantibodies is similar in HOA patients and HC, and these autoantibodies are not associated with erosive disease, structural damage, or inflammation in patients with HOA, indicating that another mechanism is driving erosive disease.

Longitudinal Reliability of the OMERACT Thumb Base Osteoarthritis Magnetic Resonance Imaging Scoring System (TOMS).

OBJECTIVE: To assess the longitudinal reliability of the Outcome Measures in Rheumatology (OMERACT) Thumb base Osteoarthritis Magnetic resonance imaging (MRI) Scoring system (TOMS). METHODS: Paired MRI of patients with hand osteoarthritis were scored in 2 exercises (6-mo and 2-yr followup) for synovitis, subchondral bone defects (SBD), osteophytes, cartilage assessment, bone marrow lesions (BML), and subluxation. Interreader reliability of delta scores was assessed. RESULTS: Little change occurred. Average-measure intraclass correlation coefficients were good-excellent (≥ 0.71), except synovitis (0.55-0.83) and carpometacarpal-1 osteophytes/cartilage assessment (0.47/0.39). Percentage exact/close agreement was 52-92%/68-100%, except BML in 2 years (28%/64-76%). Smallest detectable change was below the scoring increment, except in SBD and BML. CONCLUSION: TOMS longitudinal reliability was moderate-good. Limited change hampered assessment.

Thumb base osteoarthritis: A hand osteoarthritis subset requiring a distinct approach.

Hand osteoarthritis (OA) is usually a polyarticular disease, preferentially affecting the thumb base (TB) and interphalangeal joints. TB OA alone is generally not addressed separately, but as a part of hand OA. Studies have shown that OA in the TB joints clusters together, as does OA in the interphalangeal joints, supporting it as a distinct subset. Further support for this view comes from a specific risk profile, influence on clinical burden, impact of synovial inflammation on local joint pain, and specific treatment interventions. Therefore, clinical care and future hand OA research should not only address hand OA in general but also should focus on the different subsets separately, including TB OA.