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Updated: Jul 18, 2026
A Standardized Method for Measurement of Elbow Kinesthesia
Published on: October 10, 2020
Comparison of visual and objective quantification of elbow and shoulder movement in children with obstetric brachial
Andrea E Bialocerkowski1, Mary Galea
1Rehabilitation Sciences Research Centre, School of Physiotherapy, The University of Melbourne, VIC, 3010, Australia. aebial@unimelb.edu.au
Insights
Therapist assessments of upper limb movement in children with obstetric brachial plexus palsy (OBPP) may overestimate range of motion. Objective measurement is needed to accurately track progress and prevent long-term disability.
Area of Science:
- Pediatric Orthopedics
- Rehabilitation Medicine
- Biomechanical Analysis
Background:
- The Active Movement Scale (AMS) is widely used for children with obstetric brachial plexus palsy (OBPP).
- AMS reliability is acceptable, but its accuracy in depicting actual movements is unknown.
- This study investigates the accuracy of AMS by comparing it to objective movement quantification.
Purpose of the Study:
- To compare therapist-rated Active Movement Scale (AMS) grades with objectively measured range of motion in children with OBPP.
- To assess the agreement between visual estimation and objective quantification of upper limb movements.
- To evaluate the accuracy of the AMS in children with OBPP.
Main Methods:
- Thirty children with OBPP underwent assessment of elbow and shoulder movements.
- Therapist-rated AMS grades were recorded during facilitated play.
- Two-dimensional motion analysis (v-scope) objectively quantified movement degrees, converted to AMS grades using normative data.
- Agreement was analyzed using percentage agreement and Kappa statistics.
Main Results:
- Children with OBPP could perform movements against gravity, with AMS grades typically 5-7.
- Objective analysis showed rarely achieved full range of motion at the elbow and shoulder.
- Moderate agreement was found between methods, but therapists frequently overestimated movement, especially at the elbow.
- Agreement, adjusted for chance, was equivalent to chance.
Conclusions:
- Visual estimates of elbow and shoulder movement in OBPP may not accurately reflect true motion.
- Accurate, clinically feasible methods for quantifying upper limb movements are needed.
- Continuous monitoring and maintenance of elbow and shoulder movement are crucial to mitigate future disability.
Background:
The Active Movement Scale is a frequently used outcome measure for children with obstetric brachial plexus palsy (OBPP). Clinicians observe upper limb movements while the child is playing and quantify them on an 8 point scale. This scale has acceptable reliability however it is not known whether it accurately depicts the movements observed. In this study, therapist-rated Active Movement Scale grades were compared with objectively-quantified range of elbow flexion and extension and shoulder abduction and flexion in children with OBPP. These movements were chosen as they primarily assess the C5, C6 and C7 nerve roots, the most frequently involved in OBPP. Objective quantification of elbow and shoulder movements was undertaken by two-dimensional motion analysis, using the v-scope.
Methods:
Young children diagnosed with OBPP were recruited from the Royal Children's Hospital (Melbourne, Australia) Brachial Plexus registry. They participated in one measurement session where an experienced paediatric physiotherapist facilitated maximal elbow flexion and extension, shoulder abduction and extension through play, and quantified them on the Active Movement Scale. Two-dimensional motion analysis captured the same movements in degrees, which were then converted into Active Movement Score grades using normative reference data. The agreement between the objectively-quantified and therapist-rated grades was determined using percentage agreement and Kappa statistics.
Results:
Thirty children with OBPP participated in the study. All were able to perform elbow and shoulder movements against gravity. Active Movement Score grades ranged from 5 to 7. Two-dimensional motion analysis revealed that full range of movement at the elbow and shoulder was rarely achieved. There was moderate percentage agreement between the objectively-quantified and therapist-rated methods of movement assessment however the therapist frequently over-estimated the range of movement, particularly at the elbow. When adjusted for chance, agreement was equal to chance.
Conclusion:
Visual estimates of elbow and shoulder movement in children with OBPP may not provide true estimates of motion. Future work is required to develop accurate, clinically-acceptable methods of quantifying upper limb active movements. Since few children attained full range of motion, elbow and shoulder movement should be monitored and maintained over time to reduce disability later in life.
