RCT on Nonoperative Versus Operative Treatment for Acute Complete tearS of the Ulnar Collateral ligAment of the Thumb

The MHQ, expressed as the MHQ at 6 months (from randomization to 6 months after) is the primary endpoint of the study. The MHQ is a validated tool for assessment of functional outcome in patients with pathology of the hand. The MHQ is a questionnaire divided in six subscales; overall hand function, activities of daily living (ADLs), pain, work performance, aesthetics and patient satisfaction with hand function. Each subscale has a formula to calculate a score. The final score is a summation of the six individual item-scores divided by six and goes from 0 (severe disability) to 100 (no disability).

a self-reported, patient-specific outcome measure, designed to assess functional change, primarily in patients presenting with musculoskeletal disorders. Patients are asked to identify up to five important activities they are unable to perform or are having difficulty with as a result of their problem i.e. putting socks on. In addition to identifying the activities, patients are asked to rate, on an 11-point scale, the current level of difficulty associated with each activity. Following the intervention, patients are asked again to rate the activities previously identified and are given the chance to nominate new problematic activities that might have arisen during that time. "0" represents unable to perform, "10" represents able to perform. Patients select a value that best describes their current level of ability on each activity assessed.

a measure of health-related quality of life that can be used in a wide range of health conditions and treatments. The EQ-5D consists of a descriptive system and the EQ VAS. The descriptive system comprises five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. The EQ VAS records the patient's self-rated health on a vertical visual analogue scale. This can be used as a quantitative measure of health outcome that reflects the patient's own judgment. The score on the five dimensions can be presented as a health profile or can be converted into a utility score based on an available Dutch scoring algorithm (www.euroqol.org). The area under the curve of utility scores over time will be used to express the effect on quality of life in QALY's.

see above

will be used to assess pain, where 0 implies no pain and 10 the worst possible pain measured

will be measured by using the ICHOM Satisfaction with treatment results questionnaire (self designed by ICHOM)

to measure the amount of medical consumption due to a complete tear of the UCL (the questionnaire is adjusted for this study)

flexion and extension of the metacarpophalangeal (MCP) joint and interphalangeal joint (IP) and palmar abduction of the carpometacarpal (CMC) joint are measured with a goniometer. The first measurement is performed at both sides.

assessing the opposition of the CMC joint. The opposition test consists of touching the four long fingers with the tip of the thumb. The more the tip of the thumb is able to oppose to the base of the pink, the higher the score will be.

• Conservative treatment: pressure ulcers, neuropraxia or injury to the sensory superficial branches of radial nerve, arthrosis, chronic instability or limited function.
• Perioperative: vascular damage, nerve or tendon laceration.
• Postoperative: surgical site infection, repeat operation, pressure ulcers, neuropraxia or injury to the sensory superficial branches of radial nerve, arthrosis, chronic instability or limited function.

Peri- and postoperative complications will be recorded according tot the Clavien-Dindo Classification for hand surgery. Repeat operation and subsequent description of the additional treatment method will be reported.

to measure the amount sick leave from work or lost productivity while at work and out-of pocket expenses due to a complete tear of the UCL and the questionnaire is adjusted for this study.

measured with a hand-held dynamometer. The measurement includes three trials of maximum grip force using the second handle of a calibrated dynamometer, with the elbow in 90° flexion. Dynamometer settings will be based on patients' hand size. Each center will use the same type of dynamometer. The mean score of three trials will be used for analysis as an absolute measure. The first measurement is performed at both sides.

key pinch/lateral pinch and tip pinch will be measured. Key pinch includes three trials of maximum force between the radial side of the index finger and the pulp of the thumb, using a calibrated pinch gauge, with the elbow in 90° flexion. Tip pinch includes three trials of maximum force between the tip of the index finger and the tip of the thumb, using a calibrated pinch gauge, with the elbow in 90° flexion. Each center will use the same type of pinch gauge. The mean score of three trials will be used for analysis as an absolute measure. The first measurement is performed at both sides.