Effect of training on upper-extremity prosthetic performance and motor learning: a single-case study

Area of Science:

• Prosthetics and Orthotics
• Rehabilitation Medicine
• Human Motor Control

Background:

• Evaluating the impact of new prosthetic devices on experienced users is crucial for understanding rehabilitation outcomes.
• Assessing the efficacy of occupational therapy in mitigating initial functional decline post-prosthesis fitting is essential.

Observation:

• A single-case study involving a bilateral high-arm amputee (right shoulder disarticulation, left above elbow) was conducted.
• The participant received a new prosthesis and underwent occupational therapy interventions.
• Functional outcomes were measured using the Action Research Arm Test, box and block test, Jebsen-Taylor Hand Function Test, and reaching movement analysis.

Findings:

• Initial provision of a new prosthesis led to a functional decline, which was subsequently reversed and surpassed with occupational therapy.
• Clinical measures demonstrated significant variability (up to 300-fold) in detecting functional changes.
• Improvements correlated with increased reaching speed and accuracy without visual guidance, suggesting motor learning.

Implications:

• New prostheses can temporarily impair function even in skilled users, highlighting the importance of rehabilitation.
• The choice of clinical outcome measures significantly impacts the detection and quantification of functional improvements.
• Motor learning and user skill are critical factors in successful prosthetic rehabilitation.