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

MUlticenter Randomized Controlled Trial on Nonoperative Versus Operative Treatment for Acute Complete tearS of the Ulnar Collateral ligAment of the Thumb: Cost- Effectiveness and Functional Outcomes.

A complete rupture of the ulnar collateral ligament (UCL) of the thumb must heal in order to regain proper function of the thumb. Guidelines recommend surgery for complete UCL ruptures, including Stener lesions. This recommendation is based on expert opinion, anatomic theories and low quality retrospective case series. High quality studies comparing cast immobilization with operative treatment are lacking. Research has shown that in about 9 out of 10 patients, a complete UCL rupture, including Stener Lesions, can also be treated with a cast alone for 6 weeks and no surgery is needed. We hypothesize that cast immobilization is non-inferior regarding functional outcome and carries concomitant lower costs compared with operative treatment for complete UCL ruptures, including Stener Lesions.

The project aims to conduct a multicenter randomized controlled trial and cost-effectiveness analysis comparing operative and nonoperative treatment for complete UCL ruptures, including Stener Lesions. The project will take four years, from preparation to reporting of the results. In the following years, implementation will be achieved in collaboration with the Dutch hand surgery committees (NVvH and NVPC), health insurance companies, and medical experts.

Research question Is nonoperative treatment with splint immobilization non-inferior to immediate operative treatment regarding functional outcome and does it lead to lower costs in adult patients with an acute complete UCL rupture, including Stener Lesions?

Study Overview

• Status: Active, not recruiting
• Conditions: Ulnar Collateral Ligament Sprain; Skier's Thumb
• Intervention / Treatment: Procedure: Cast immobilization; Procedure: Surgical treatment

• Study Type: Interventional
• Enrollment (Estimated): 126
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Utrecht, Netherlands, 3582KE
    • Diakonessenhuis Utrecht

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients 18 years and older
• Dutch or English speaking patients

• Patients with an acute complete UCL rupture, with or without a Stener Lesion, diagnosed using physical examination, performed by the hand surgeon. When providing radically directed force to the proximal phalanx (radial deviation stress) as the thumb metacarpal is stabilized, criteria 1 AND 2 must be present to confirm the diagnosis of a complete UCL rupture:

  • no firm endpoint in the MCP joint AND
  • at least more than 35 degrees of laxity in the MCP joint (measured with the MCP joint in extension or in 30 degrees of flexion) OR more than 15 degrees difference in laxity compared with the uninjured side.

Exclusion Criteria:

-

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cast immobilization; Cast immobilization to immobilize the thumb for 4 weeks. After 2 weeks the thumb will be re-examined to determine if surgery is required. It is expected that at re-evaluation at 2 weeks after starting the cast treatment about 1 in 10 patients will still need surgery.	Procedure: Cast immobilization; A cast to immobilize the MCP, in 10-30 degrees (slight) flexion (neutral position), and the CMC joint, in 30-40 degrees palmar abduction, is applied (IP joint is free).
Active Comparator: Surgery; The intervention is compared to surgery, which is standard treatment for complete ulnar collateral ligament ruptures.	Procedure: Surgical treatment; In general, two surgical techniques are described in literature and used in daily clinical practice: If the UCL is ruptured in the middle of the ligament, sutures are used to reattach the ligament remnants together.; When no viable UCL ligaments are present, the UCL is reattached directly to the bone using suture anchors.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Michigan Hand outcome Questionnaire (MHQ)	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).	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient-Specific Functional Scale (PSFS)	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.	at randomization, 2, 3, 6 and 12 months after randomization.
EQ-5D-5L	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.	at randomization, 2, 3, 6 and 12 months after randomization.
Michigan Hand outcome Questionnaire (MHQ)	see above	at randomization, 2, 3 and 12 months after randomization.
The Numeric Pain Rating Scale (NPRS)	will be used to assess pain, where 0 implies no pain and 10 the worst possible pain measured	at randomization, 2, 3, 6 and 12 months after randomization.
Patient satisfaction	will be measured by using the ICHOM Satisfaction with treatment results questionnaire (self designed by ICHOM)	at randomization, 2, 3, 6 and 12 months after randomization.
The adapted Dutch institute for Medical Technology Assessment (iMTA) Medical Consumption Questionnaire (iMCQ)	to measure the amount of medical consumption due to a complete tear of the UCL (the questionnaire is adjusted for this study)	at 2 months (over the last 2 months), 3 (over the last month), 6 (over the last 3 months), and 12 (over the last 3 months) months after randomization
Range of motion (ROM)	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.	4 weeks, 3, 6 and 12 months after randomization.
Kapandji-score	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.	4 weeks, 3, 6 and 12 months after randomization.
Complications	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.	4 weeks, 3, 6 and 12 months after randomization.
The adapted Dutch institute for Medical Technology Assessment (iMTA)Productivity Cost Questionnaire (iPCQ)	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.	at 2 months (over the last 2 months), 3 (over the last month), 6 (over the last 3 months), and 12 (over the last 3 months) months after randomization
Grip strength	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.	4 weeks, 3, 6 and 12 months after randomization.
Pinch strength	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.	4 weeks, 3, 6 and 12 months after randomization.

Collaborators and Investigators

• Sponsor: Diakonessenhuis, Utrecht
• Collaborators: ZonMw: The Netherlands Organisation for Health Research and Development
• Investigators: Principal Investigator: Mark van Heijl, MD, PhD, Diakonessenhuis, Utrecht

Publications and helpful links

General Publications

• Pulos N, Shin AY. Treatment of Ulnar Collateral Ligament Injuries of the Thumb: A Critical Analysis Review. JBJS Rev. 2017 Feb 21;5(2):e3. doi: 10.2106/JBJS.RVW.16.00051. No abstract available.
• Pichora DR, McMurtry RY, Bell MJ. Gamekeepers thumb: a prospective study of functional bracing. J Hand Surg Am. 1989 May;14(3):567-73. doi: 10.1016/s0363-5023(89)80026-7.
• Landsman JC, Seitz WH Jr, Froimson AI, Leb RB, Bachner EJ. Splint immobilization of gamekeeper's thumb. Orthopedics. 1995 Dec;18(12):1161-5. doi: 10.3928/0147-7447-19951201-06.
• Samora JB, Harris JD, Griesser MJ, Ruff ME, Awan HM. Outcomes after injury to the thumb ulnar collateral ligament--a systematic review. Clin J Sport Med. 2013 Jul;23(4):247-54. doi: 10.1097/JSM.0b013e318289c6ff.
• Mikhail M, Wormald JCR, Thurley N, Riley N, Dean BJF. Therapeutic interventions for acute complete ruptures of the ulnar collateral ligament of the thumb: a systematic review. F1000Res. 2018 Jun 8;7:714. doi: 10.12688/f1000research.15065.1. eCollection 2018.

Study record dates

Study Major Dates

• Study Start (Actual): February 17, 2022
• Primary Completion (Estimated): October 1, 2025
• Study Completion (Estimated): July 31, 2026

Study Registration Dates

• First Submitted: March 3, 2022
• First Submitted That Met QC Criteria: March 21, 2022
• First Posted (Actual): March 22, 2022

Study Record Updates

• Last Update Posted (Actual): August 21, 2025
• Last Update Submitted That Met QC Criteria: August 20, 2025
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Other Study ID Numbers: NL78886.100.21

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: An official Data Management Plan has been developed, in accordance with the official format used in the Netherlands.
• IPD Sharing Time Frame: When the manuscripts are published
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No