Trial Outcomes & Findings for LRTI vs Internal Brace for CMC OA (NCT NCT03971188)

NCT ID: NCT03971188

Last Updated: 2025-04-06

Results Overview

The investigators will establish feasibility of a definitive trial by determining the proportion of eligible subjects who agree to randomized treatment and determining follow-up retention rate.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 31 participants
• Primary outcome timeframe: 12 months
• Results posted on: 2025-04-06

Participant Flow

Patients were prospectively randomized to LRTI or STS over a 2- year period (December 2019 to December 2021). The enrollment period was prolonged because of the coronavirus disease 2019 pandemic. Potential study participants were identified as they presented to the clinics of five hand surgeons at a single academic medical center.

Forty-one patients (42 thumbs) agreed to randomization out of a total of 51 patients (52 thumbs) offered participation. One patient had staged bilateral thumb CMC OA surgery one year apart. Ten patients who initially consented to participate subsequently declined; seven decided against randomization and three elected to forego surgery and continue nonsurgical management. A total of 31 patients (32 thumbs) were randomized out of 51 patients (52 thumbs) offered participation.

Unit of analysis: thumbs

Participant milestones

Measure	Internal Brace Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Overall Study STARTED	16 17	15 15
Overall Study COMPLETED	16 17	15 15
Overall Study NOT COMPLETED	0 0	0 0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

LRTI vs Internal Brace for CMC OA

Baseline characteristics by cohort

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	Total n=32 thumbs Total of all reporting groups
Age, Continuous	62 years STANDARD_DEVIATION 8 • n=17 thumbs	61 years STANDARD_DEVIATION 8 • n=15 thumbs	62 years STANDARD_DEVIATION 8 • n=32 thumbs
Sex: Female, Male Female	12 thumbs n=17 thumbs	12 thumbs n=15 thumbs	24 thumbs n=32 thumbs
Sex: Female, Male Male	5 thumbs n=17 thumbs	3 thumbs n=15 thumbs	8 thumbs n=32 thumbs
Race/Ethnicity, Customized Race · Black	0 thumbs n=17 thumbs	2 thumbs n=15 thumbs	2 thumbs n=32 thumbs
Race/Ethnicity, Customized Race · White	16 thumbs n=17 thumbs	13 thumbs n=15 thumbs	29 thumbs n=32 thumbs
Race/Ethnicity, Customized Race · Other	1 thumbs n=17 thumbs	0 thumbs n=15 thumbs	1 thumbs n=32 thumbs
Region of Enrollment United States	17 thumbs n=17 thumbs	15 thumbs n=15 thumbs	32 thumbs n=32 thumbs
Current smoker Yes	1 thumbs n=17 thumbs	2 thumbs n=15 thumbs	3 thumbs n=32 thumbs
Current smoker No	16 thumbs n=17 thumbs	13 thumbs n=15 thumbs	29 thumbs n=32 thumbs
Diabetes Yes	3 thumbs n=17 thumbs	2 thumbs n=15 thumbs	5 thumbs n=32 thumbs
Diabetes No	14 thumbs n=17 thumbs	13 thumbs n=15 thumbs	27 thumbs n=32 thumbs
Prior ipsilateral hand surgery Yes	4 thumbs n=17 thumbs	8 thumbs n=15 thumbs	12 thumbs n=32 thumbs
Prior ipsilateral hand surgery No	13 thumbs n=17 thumbs	7 thumbs n=15 thumbs	20 thumbs n=32 thumbs
Prior contralateral hand surgery Yes	4 thumbs n=17 thumbs	5 thumbs n=15 thumbs	9 thumbs n=32 thumbs
Prior contralateral hand surgery No	13 thumbs n=17 thumbs	10 thumbs n=15 thumbs	23 thumbs n=32 thumbs
Preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety Score	48 T-score STANDARD_DEVIATION 9 • n=5 Participants	51 T-score STANDARD_DEVIATION 10 • n=7 Participants	49 T-score STANDARD_DEVIATION 9 • n=5 Participants
Pre-op PROMIS Depression Score	47 T-score STANDARD_DEVIATION 8 • n=5 Participants	46 T-score STANDARD_DEVIATION 10 • n=7 Participants	46 T-score STANDARD_DEVIATION 9 • n=5 Participants
Work status Working	11 Participants n=5 Participants	6 Participants n=7 Participants	17 Participants n=5 Participants
Work status Retired	5 Participants n=5 Participants	9 Participants n=7 Participants	14 Participants n=5 Participants

PRIMARY outcome

Timeframe: 12 months

The investigators will establish feasibility of a definitive trial by determining the proportion of eligible subjects who agree to randomized treatment and determining follow-up retention rate.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Postoperative Follow-Up Retention Rate 3-month follow-up · Yes	17 thumbs	13 thumbs
Postoperative Follow-Up Retention Rate 3-month follow-up · No	0 thumbs	2 thumbs
Postoperative Follow-Up Retention Rate 1-year follow-up · Yes	17 thumbs	14 thumbs
Postoperative Follow-Up Retention Rate 1-year follow-up · No	0 thumbs	1 thumbs

PRIMARY outcome

Timeframe: 12 months

Visual Analog Scale (VAS) Pain scores will be collected by a member of our team at all visits. These scores will be compared pre-op and at 2 weeks, 4 weeks, 3 months, and 1 year post-op. Scale ranges from 0 to 10 points. For Pain, 0 indicates no pain and 10 indicates maximum pain.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
VAS Pain Scores Pre-op	7.4 score on a scale Standard Deviation 1.3	7.7 score on a scale Standard Deviation 1.7
VAS Pain Scores 2 week	3.9 score on a scale Standard Deviation 2.3	2.9 score on a scale Standard Deviation 2.1
VAS Pain Scores 4 week	3.1 score on a scale Standard Deviation 2.3	1.8 score on a scale Standard Deviation 1.2
VAS Pain Scores 3 month	2.5 score on a scale Standard Deviation 2.3	1.6 score on a scale Standard Deviation 1.1
VAS Pain Scores 1 year	2.4 score on a scale Standard Deviation 2.5	2.4 score on a scale Standard Deviation 2.9

PRIMARY outcome

Timeframe: 12 months

PROMIS Upper Extremity scores will be collected at all clinic visits on iPad as per standard protocol for all patients presenting to a Washington University Orthopaedic Surgery clinic. These scores will be compared pre-op and at 2 weeks, 4 weeks, 3 months, and 1 year post-op. All PROMIS domain scores are normalized to a mean score of 50 and standard deviation of 10 intending to minimize floor and ceiling effects and ensure the results are readily understood and communicated. A higher score indicates better upper extremity function.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity Scores Pre-op	32.7 T-score Standard Deviation 4.8	36.0 T-score Standard Deviation 8.0
Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity Scores 2 week	27.0 T-score Standard Deviation 4.6	29.6 T-score Standard Deviation 6.9
Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity Scores 4 week	31.7 T-score Standard Deviation 5.6	35.6 T-score Standard Deviation 7.1
Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity Scores 3 month	38.6 T-score Standard Deviation 7.3	42.7 T-score Standard Deviation 7.8
Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity Scores 1 year	41.5 T-score Standard Deviation 9.8	46.7 T-score Standard Deviation 6.6

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb IP Joint Extension Pre-op	18 Degrees Standard Deviation 12	19 Degrees Standard Deviation 9
Thumb Range of Motion: Thumb IP Joint Extension 4 week	13 Degrees Standard Deviation 12	11 Degrees Standard Deviation 10
Thumb Range of Motion: Thumb IP Joint Extension 3 month	11 Degrees Standard Deviation 11	21 Degrees Standard Deviation 10
Thumb Range of Motion: Thumb IP Joint Extension 1 year	17 Degrees Standard Deviation 14	20 Degrees Standard Deviation 14

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb IP Joint Flexion Pre-op	49 Degrees Standard Deviation 14	44 Degrees Standard Deviation 17
Thumb Range of Motion: Thumb IP Joint Flexion 4 week	41 Degrees Standard Deviation 14	32 Degrees Standard Deviation 20
Thumb Range of Motion: Thumb IP Joint Flexion 3 month	51 Degrees Standard Deviation 12	50 Degrees Standard Deviation 12
Thumb Range of Motion: Thumb IP Joint Flexion 1 year	52 Degrees Standard Deviation 10	56 Degrees Standard Deviation 13

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb MCP Joint Extension Pre-op	9 Degrees Standard Deviation 10	14 Degrees Standard Deviation 10
Thumb Range of Motion: Thumb MCP Joint Extension 4 week	7 Degrees Standard Deviation 8	5 Degrees Standard Deviation 6
Thumb Range of Motion: Thumb MCP Joint Extension 3 month	9 Degrees Standard Deviation 11	7 Degrees Standard Deviation 8
Thumb Range of Motion: Thumb MCP Joint Extension 1 year	8 Degrees Standard Deviation 7	10 Degrees Standard Deviation 12

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb MCP Joint Flexion Pre-op	44 Degrees Standard Deviation 12	48 Degrees Standard Deviation 10
Thumb Range of Motion: Thumb MCP Joint Flexion 4 week	29 Degrees Standard Deviation 11	22 Degrees Standard Deviation 11
Thumb Range of Motion: Thumb MCP Joint Flexion 3 month	32 Degrees Standard Deviation 11	39 Degrees Standard Deviation 8
Thumb Range of Motion: Thumb MCP Joint Flexion 1 year	35 Degrees Standard Deviation 10	47 Degrees Standard Deviation 9

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb CMC Joint Palmar Abduction Pre-op	47 Degrees Standard Deviation 6	40 Degrees Standard Deviation 11
Thumb Range of Motion: Thumb CMC Joint Palmar Abduction 4 week	47 Degrees Standard Deviation 4	45 Degrees Standard Deviation 6
Thumb Range of Motion: Thumb CMC Joint Palmar Abduction 3 month	48 Degrees Standard Deviation 8	49 Degrees Standard Deviation 6
Thumb Range of Motion: Thumb CMC Joint Palmar Abduction 1 year	47 Degrees Standard Deviation 6	50 Degrees Standard Deviation 5

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb CMC Joint Palmar Adduction Pre-op	16 Degrees Standard Deviation 10	23 Degrees Standard Deviation 4
Thumb Range of Motion: Thumb CMC Joint Palmar Adduction 4 week	23 Degrees Standard Deviation 7	27 Degrees Standard Deviation 5
Thumb Range of Motion: Thumb CMC Joint Palmar Adduction 3 month	16 Degrees Standard Deviation 9	21 Degrees Standard Deviation 4
Thumb Range of Motion: Thumb CMC Joint Palmar Adduction 1 year	19 Degrees Standard Deviation 6	21 Degrees Standard Deviation 4

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb CMC Joint Radial Abduction Pre-op	45 Degrees Standard Deviation 6	42 Degrees Standard Deviation 11
Thumb Range of Motion: Thumb CMC Joint Radial Abduction 4 week	45 Degrees Standard Deviation 7	39 Degrees Standard Deviation 6
Thumb Range of Motion: Thumb CMC Joint Radial Abduction 3 month	49 Degrees Standard Deviation 11	42 Degrees Standard Deviation 9
Thumb Range of Motion: Thumb CMC Joint Radial Abduction 1 year	45 Degrees Standard Deviation 10	49 Degrees Standard Deviation 7

SECONDARY outcome

Timeframe: 12 months

Thumb ROM at carpometacarpal, metacarpophalangeal, and interphalangeal joints will be collected by a member of our team at baseline, 4 weeks, 3 months, and 1 year after surgery. These values will be reported in degrees and compared between the two groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Range of Motion: Thumb CMC Joint Radial Adduction Pre-op	15 Degrees Standard Deviation 11	17 Degrees Standard Deviation 10
Thumb Range of Motion: Thumb CMC Joint Radial Adduction 4 week	23 Degrees Standard Deviation 8	21 Degrees Standard Deviation 9
Thumb Range of Motion: Thumb CMC Joint Radial Adduction 3 month	15 Degrees Standard Deviation 9	17 Degrees Standard Deviation 9
Thumb Range of Motion: Thumb CMC Joint Radial Adduction 1 year	18 Degrees Standard Deviation 8	18 Degrees Standard Deviation 9

SECONDARY outcome

Timeframe: 12 months

The investigators will record grip strength PRE-OP and POST-OP (all visits except 2 weeks post-op) in both the operative hands. Grip strength will be measured using dynamometer and recorded in pounds (lbs).

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Grip Strength Pre-op	37 Pounds (lbs) Standard Deviation 17	48 Pounds (lbs) Standard Deviation 29
Grip Strength 4 week	26 Pounds (lbs) Standard Deviation 11	22 Pounds (lbs) Standard Deviation 21
Grip Strength 3 month	41 Pounds (lbs) Standard Deviation 16	46 Pounds (lbs) Standard Deviation 24
Grip Strength 1 year	56 Pounds (lbs) Standard Deviation 17	63 Pounds (lbs) Standard Deviation 20

SECONDARY outcome

Timeframe: 12 months

The investigators will record pinch strength PRE-OP and POST-OP (all visits except 2 weeks post-op) in the operative hand. Pinch strength will be measured using a pinch gauge and recorded in pounds (lbs). For pinch, the investigators will record "lateral/key pinch" AND "3-point pinch."

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Pinch Strength: Lateral Pinch Pre-op	9 Pounds (lbs) Standard Deviation 4	11 Pounds (lbs) Standard Deviation 6
Pinch Strength: Lateral Pinch 4 week	5 Pounds (lbs) Standard Deviation 3	3 Pounds (lbs) Standard Deviation 3
Pinch Strength: Lateral Pinch 3 month	9 Pounds (lbs) Standard Deviation 3	10 Pounds (lbs) Standard Deviation 5
Pinch Strength: Lateral Pinch 1 year	13 Pounds (lbs) Standard Deviation 4	13 Pounds (lbs) Standard Deviation 5

SECONDARY outcome

Timeframe: 12 months

The investigators will record pinch strength PRE-OP and POST-OP (all visits except 2 weeks post-op) in the operative hand. Pinch strength will be measured using a pinch gauge and recorded in pounds (lbs). For pinch, the investigators will record "lateral/key pinch" AND "3-point pinch."

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Pinch Strength: Three-Point Pinch Pre-op	8 Pounds (lbs) Standard Deviation 6	9 Pounds (lbs) Standard Deviation 4
Pinch Strength: Three-Point Pinch 4 week	4 Pounds (lbs) Standard Deviation 2	2 Pounds (lbs) Standard Deviation 3
Pinch Strength: Three-Point Pinch 3 month	7 Pounds (lbs) Standard Deviation 3	11 Pounds (lbs) Standard Deviation 6
Pinch Strength: Three-Point Pinch 1 year	11 Pounds (lbs) Standard Deviation 3	12 Pounds (lbs) Standard Deviation 4

SECONDARY outcome

Timeframe: 12 months

Posteroanterior wrist and Roberts view C-arm XRs from pre-op, 3 months post-op, and 1 year post-op were obtained. Thumb metacarpal subsidence was calculated using the trapezial space ratio (TSR) measured on a posteroanterior wrist radiograph.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Thumb Metacarpal Radiographic Subsidence: Trapezial Space Ratio Reduction 3 months	48 Percent reduction of TSR Standard Deviation 22.4	42 Percent reduction of TSR Standard Deviation 13.6
Thumb Metacarpal Radiographic Subsidence: Trapezial Space Ratio Reduction 1 year	55 Percent reduction of TSR Standard Deviation 18.4	46 Percent reduction of TSR Standard Deviation 12.2

SECONDARY outcome

Timeframe: 12 months

The investigators will track return to work/activity by asking patients at each follow-up visit (1) IF they have returned to their work and baseline activity, and (2) if so, HOW LONG AFTER THEIR SURGERY did they return (ie, 2 weeks, 4 weeks, 6 weeks, 2 mos, 2.5 mos, 3 mos, 4 mos, 5 mos, >6 mos). Return to work and activity will be compared between the two treatment groups.

Outcome measures

Measure	Internal Brace n=17 thumbs Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 thumbs Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Return to Work/Activity 2 week · Yes	4 thumbs	7 thumbs
Return to Work/Activity 2 week · No	13 thumbs	8 thumbs
Return to Work/Activity 4 week · Yes	8 thumbs	9 thumbs
Return to Work/Activity 4 week · No	9 thumbs	6 thumbs
Return to Work/Activity 3 month · Yes	13 thumbs	14 thumbs
Return to Work/Activity 3 month · No	4 thumbs	1 thumbs
Return to Work/Activity 1 year · Yes	17 thumbs	15 thumbs
Return to Work/Activity 1 year · No	0 thumbs	0 thumbs

Adverse Events

Internal Brace

Serious events: 1 serious events

Other events: 4 other events

Deaths: 0 deaths

LRTI

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Measure	Internal Brace n=17 participants at risk Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 participants at risk Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Musculoskeletal and connective tissue disorders Concern for deep surgical site infection	5.9% 1/17 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	0.00% 0/15 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).

Other adverse events

Measure	Internal Brace n=17 participants at risk Patients will undergo Internal Brace procedure for thumb CMC OA. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.	LRTI n=15 participants at risk Patients will undergo ligament reconstruction tendon interposition (most commonly performed surgery for thumb CMC OA) and serve as control group. Trapeziectomy with Internal Brace: Trapeziectomy is performed in standard fashion. Longitudinal traction applied to thumb. Suture anchor with suture tape is inserted into drill hole at radial thumb metacarpal base. A second suture anchor is inserted into a drill hole at the radial base of the index metacarpal such that the suture tape suspends the thumb at the natural groove. Thumb position and tension assessed.
Musculoskeletal and connective tissue disorders Persistent thumb base pain pain	0.00% 0/17 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	6.7% 1/15 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).
Musculoskeletal and connective tissue disorders Painless first metacarpal osteolysis	5.9% 1/17 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	0.00% 0/15 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).
Musculoskeletal and connective tissue disorders Hypersensitivity of thumb	5.9% 1/17 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	0.00% 0/15 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).
Musculoskeletal and connective tissue disorders Superficial skin infection	5.9% 1/17 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	0.00% 0/15 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).
Musculoskeletal and connective tissue disorders Fall with wrist injury	5.9% 1/17 • Number of events 1 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).	0.00% 0/15 • One year Mild complications were defined as having minor clinical impact (eg, scar tenderness or sensory disturbances). Moderate complications were defined as clinically relevant with delay in patient recovery but resolved by 1-year and not severe enough to need revision surgery (eg, superficial infections, mild CRPS type I). Severe complications were those that resulted in revision surgery or impaired hand function at 1-year (eg, deep infections requiring irrigation \& debridement, severe CRPS type I).

Additional Information

Dr. Charles Goldfarb

Washington University in St. Louis

Phone: (314) 362-3768

Email: goldfarbc@wustl.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place