Reliability of three classification systems measuring active motion in brachial plexus birth palsy

Area of Science:

• Orthopedics
• Pediatric Rehabilitation
• Clinical Measurement

Background:

• Established classification systems for brachial plexus birth palsy (BPBP) function are varied.
• Reliability of existing assessment tools is crucial for consistent patient evaluation.

Purpose of the Study:

• To determine the intraobserver and interobserver reliability of the modified Mallet Classification (mMC), Toronto Test Score (TTS), and Hospital for Sick Children Active Movement Scale (HSC-AMS).
• To assess the reliability of these instruments in evaluating upper-extremity function in children with BPBP.

Main Methods:

• Eighty children with BPBP were evaluated by two examiners on two separate occasions.
• Intraobserver and interobserver reliability were assessed using the kappa statistic.
• Internal consistency was determined using Cronbach's alpha.

Main Results:

• Good to excellent intraobserver reliability was found for individual elements of mMC, TTS, and HSC-AMS across all age groups.
• Interobserver reliability for individual elements ranged from fair to excellent.
• Aggregate TTS and mMC scores demonstrated excellent internal consistency (test-retest reliability) and strong positive correlations for both intraobserver and interobserver assessments.

Conclusions:

• The modified Mallet Classification, Toronto Test Score, and Active Movement Scale are reliable instruments for assessing upper-extremity function in patients with brachial plexus birth palsy.
• These validated tools can be confidently used for future studies on the natural history and surgical outcomes of BPBP.