Brachial Plexus Birth Palsy: Reinforcement Paradigm to Augment Recovery

Study Details

Brief summary:

Infants who sustain an injury to the brachial plexus in the perinatal period are at high-risk for long-term neuromuscular deficits and prehensile dysfunction. If recovery is delayed because of slow axonal regrowth, disuse atrophy and secondary musculoskeletal deficits may develop. The investigators' hypothesis is that early, intensive intervention designed to foster muscle activation is essential to optimize outcomes after brachial plexus injury and may supplement rehabilitation and microsurgery. This proposal targets infants who are non-surgical candidates. Yet, future studies will examine whether the investigators' experimental intervention can hasten recovery from microsurgery and will examine which post-operative time-point is best to employ it. The investigators' intervention shows promise to increase muscle activation and improve arm function in infants with brachial plexus birth palsy (BPBP) through contingent reinforcement based on a pilot study.

Conditions

Brachial Plexus Palsy

Study ID

NCT03886792

Start date

Feb 25, 2019

Status verified date

Jan, 2021

Completion date

Dec 31, 2021

Anticipated

Primary completion date

Dec 31, 2021

Anticipated

Eligibility Criteria

Sex: All

Age: 0 - 1

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Age of 3 to 12 months with upper trunk brachial plexus birth palsy confirmed by an attending Hand and Upper Extremity Surgeon;
2. Full-term at birth;
3. A minimum score of '1' (0-7 scale) in elbow flexion of affected arm (isometric contraction) based on the Active Movement Scale (AMS);
4. Score ≥ 25th percentile on the motor subtest of the Bayley Scales of Infant and Toddler Development, 3rd Edition (BSITD-III®);
5. Ability to sustain attention/arousal for a 10 minute training period based on criteria from the Neonatal Behavioral Assessment for an awake-alert state.

Exclusion Criteria:

1. Visual/auditory deficits;
2. Nerve repair/shoulder surgery;
3. Excessive crying during session(s);
4. Shoulder, elbow, or wrist joint contractures > 20° in the affected arm;
5. An inability to trigger the musical-toy to play at baseline.

Study Design

Enrollment

24 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Triggered Reinforcement

This group will participate in a home-based experimental intervention for 10 minutes, twice/day for 10 days within 2 weeks. The infants will be supported in sitting with a tray secured anterior to the trunk. This intervention will involve reinforcement of biceps muscle activation in the affected arm if the infant generates a muscle contraction above a pre-set threshold (V). The threshold needed to trigger a toy to move and make sounds (reinforcement) will be set at baseline as determined by surface electromyography (SEMG). During the training time-points, the parent or care-giver will be allowed to sing or talk to the infant but are not to shake the toys or place dowel-based rattles or toys in either palm of the infant.

sham comparator: Social Interaction

This group will participate in a home-based dose-equivalent control intervention for 10 minutes, twice/day for 10 days within 2 weeks. The infants will be supported in sitting with a tray. This control program will combine social interaction between infant/parent with the opportunity for self-initiated play with toys repeatedly placed on the tray. A toy will be placed in front of the infant seat and tray but it will not be connected to the SEMG unit nor will the infant have an SEMG electrode attached over the biceps. During the intervention, the parent or care-giver will be allowed to sing or talk to the infant but are not to shake the toys or place dowel-based rattles or toys in either palm of the infant.

Interventions

Triggered reinforcement

This group will participate in a home-based experimental intervention for 10 minutes, twice/day for 10 days within 2 weeks. The infants will be supported in sitting with a tray secured anterior to the trunk. This intervention will involve reinforcement of biceps muscle activation in the affected arm if the infant generates a muscle contraction above a pre-set threshold (V). The threshold needed to trigger a toy to move and make sounds (reinforcement) will be set at baseline as determined by surface electromyography (SEMG). During the training time-points, the parent or care-giver will be allowed to sing or talk to the infant but are not to shake the toys or place dowel-based rattles or toys in either palm of the infant.

Social interaction

This group will participate in a home-based dose-equivalent control intervention for 10 minutes, twice/day for 10 days within 2 weeks. The infants will be supported in sitting with a tray. This control program will combine social interaction between infant/parent with the opportunity for self-initiated play with toys repeatedly placed on the tray. A toy will be placed in front of the infant seat and tray but it will not be connected to the SEMG unit nor will the infant have an SEMG electrode attached over the biceps. During the intervention, the parent or care-giver will be allowed to sing or talk to the infant but are not to shake the toys or place dowel-based rattles or toys in either palm of the infant.

Primary outcome measure

Change in the integral of biceps brachii muscle activation post-intervention [ Time Frame: Baseline, Immediately post-intervention, 1-month post-intervention, 3-months post-intervention ]