Osteoarthritis in the Carpometacarpal (CMC) Joint
Conditions
Keywords
thumb base, osteoarthritis, PROM, trapeziectomy, joint replacement, CMC-1
Brief summary
Thumb carpometacarpal (CMC-1) osteoarthritis is a common condition causing pain and disability, particularly among middle-aged and older women. When non-operative treatment fails, surgery is indicated. In Sweden, trapeziectomy (TE), with or without tendon-based adjuncts, is the standard procedure and recommended in the National Care Program introduced in 2022. However, total joint arthroplasty (TJA) has gained popularity because of reports of faster recovery and improved early function, although concerns remain regarding complications, durability, and cost. Comparative studies are therefore needed. The aim of this study is to compare patient-reported outcomes after dual-mobility TJA versus TE, with or without tendon-based adjuncts, for CMC-1 osteoarthritis using data from the Swedish Hand Surgery Quality Register (HAKIR). To reduce bias in observational data, the study will emulate a hypothetical randomized target trial. This registry-based cohort study will include adults aged 45 years or older undergoing primary surgery for CMC-1 osteoarthritis. Patients with previous CMC-1 surgery, bilateral procedures, inflammatory joint disease, or extensive missing baseline data will be excluded. Baseline is defined as the date of surgery, and patients will be followed using patient-reported outcome measures collected preoperatively and at 3 and 12 months. The primary outcome is change in pain on load measured with the HQ-8 questionnaire at 12 months. Secondary outcomes include pain at 3 months, low pain levels at 12 months, other HQ-8 domains, QuickDASH score, patient satisfaction, grip and pinch strength, thumb range of motion, time to reoperation, and postoperative complications. Potential confounders will be identified using a directed acyclic graph (DAG). Measured confounders include age, sex, surgical centre, calendar year, baseline pain, baseline function, and smoking. Unmeasured factors such as surgeon preference, patient preference, and disease severity not captured in the registry may still cause residual confounding. Primary analyses will use linear mixed-effects regression to compare adjusted mean pain outcomes between groups at 12 months while accounting for clustering by patient and centre. Secondary outcomes will be analysed using ordinal logistic regression, Cox proportional hazards regression, and logistic regression. Missing data will be handled using multiple imputation, and sensitivity analyses using inverse probability weighting will assess the impact of reoperations and selection bias
Interventions
None listed
Sponsors
Karolinska Institutet
Erasmus Medical Center
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
45 Years to No maximum
Healthy volunteers
No
Inclusion criteria
adults aged ≥45 years with a diagnosis of CMC-1 osteoarthritis (ICD-10 code M18) who have failed non-operative treatment and are scheduled for primary CMC-1 surgery.
Exclusion criteria
* Bilateral CMC-1 surgery or other simultaneous hand interventions * Previous CMC-1 surgery on the affected hand * Inflammatory joint disease affecting the hands (e.g., rheumatoid arthritis, systemic lupus erythematosus) * 30% missing baseline (preoperative) variables
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change from baseline to 12 months in pain on load motion measured with the HAKIR questionnaire. | Baseline and 12 months postoperatively | Pain on load motion assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from baseline to 12 months in pain on unloaded motion measured with the HAKIR questionnaire | Baseline and 12 months after surgery | Pain on unloaded motion assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
| Change from baseline to 12 months in pain at rest measured with the HQ-8 questionnaire | Baseline and 12 months postoperatively | Pain at rest assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
| Change from baseline to 12 months in stiffness measured with the HQ-8 questionnaire | Baseline and 12 months postoperatively | Stiffness assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
| Change from baseline to 12 months in weakness measured with the HQ-8 questionnaire | Baseline and 12 months postoperatively | Weakness assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
| Change from baseline to 12 months in activities of daily living measured with the HQ-8 questionnaire | Baseline and 12 months postoperatively | Activities of daily living assessed using the HQ-8 patient-reported outcome questionnaire. Responses are reported on an 11-point numerical rating scale ranging from 0 (no symptoms or discomfort) to 100 (worst imaginable symptoms or discomfort) in increments of 10. |
| Change from baseline to 12 months in Quick Disabilities of Arm, Shoulder and Hand Questionnaire (Quick DASH) | Baseline and 12 months postoperatively | Upper extremity disability and symptoms assessed using the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire. Scores range from 0 to 100, where higher scores indicate greater disability and worse upper extremity function. |
| Change in key pinch strength | Baseline and 12 months postoperatively | kg |
| Change in grip strength | Baseline and 12 months postoperatively | jamar (kg) |
| Change in thumb radial abduction | Baseline and 12 months postoperatively | radial abduction (degrees) |
| Change in thumb plamar abduction | From preoperatively to 12 months postoperatively | palmar abduction (degrees) |
| Time to first reoperation* of the index hand | primary horizon: 12 months; secondary: maximum available follow-up | — |
| Risk of any (non-reoperation) complication within 12 months | within 12 months after surgery | occurrence of any registered postoperative complication of the index hand recorded in HAKIR |
Outcome results
None listed