Compensatory Movements With Axon-Hook and Greifer in Transradial Amputees

Otto Bock Healthcare (Ottobock)

Status: Completed

Conditions: Transradial Amputation

Treatments: Device: Axon-Hook then Greifer; Device: Greifer then Axon-Hook

Study type: Interventional

Funder types: Industry

Identifiers

NCT04522349

2016-A00897-44 (Other Identifier)

20PT003-FR-01-0516

Details and patient eligibility

About

Upper limb amputees often report musculoskeletal pain due to exaggerated shoulder abduction movements. Previous studies on prosthetic hands showed that wrist orientation contributes to reduce shoulder compensatory movements. The hypothesis of this research is that prosthetic hooks may also provide better functional outcomes when offering wrist adjustments and a design that favors a good visualization of the grips. The objective of this study is to compare shoulder abduction, manual dexterity and satisfaction when using Axon-Hook and Greifer myoelectric hooks during repetitive tasks. Shoulder abduction and manual dexterity results are also compared with the sound side.

Full description

Depending on patient's expectations, different prosthetic solutions can be offered. If prosthetic hands, being at the same time functional and aesthetic solutions, are widely used, for some professional or leisure activities, myoelectric users will have a better functional response with a non-morphologic terminal device such as a hook.

Axon-hook and Greifer are two myoelectric hooks proposed by Otto Bock HealthCare. Greifer (Myobock system) has two movable strong hooks and a wrist that can be orientated medially or laterally. Axon-Hook (Axon-Bus system) has thin hooks for a good visualization of the grip, one being fixed for more precision, and a flexible wrist that can be orientated and locked in flexion and extension position.

Previous studies on myoelectric hands showed that functionalities of prosthetic components such as type of hand or type of wrist, have an influence on compensatory movements, which can explain musculoskeletal pains. The hypothesis of the study is that Axon-Hook may reduce shoulder abduction and improve patient satisfaction. No significant difference is expected regarding manual dexterity.

This randomized corossover trial compares shoulder abduction, manual dexterity and satisfaction while using Axon-Hook and Greifer. Shoulder abduction and manual dexterity results are also compared with the sound side.

Enrollment: 8 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• persons with trans-radial upper limb amputation
• persons whose amputation is acquired or congenital
• persons who regularily uses a myoelectric prosthesis and who controls it
• persons whose residual limb is stabilized, with a minimum time of six month since amputation
• persons whose profesional activity or life project justify or could justify the use of a myoelectric hook
• persons who gave their written consent to participate to the study

Exclusion criteria

• persons under 18 years of age
• pregnant woman
• persons unable to personnaly give their consent
• persons with psychic or linguistic inability to understand instructions for the test
• persons unavailable to comply with the entire study protocol

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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8 participants in 2 patient groups

Greifer then Axon-Hook

Active Comparator group

Description:

T0 + 2 weeks: evaluation with Greifer. T1 + 2 weeks: evaluation with Axon-Hook

Treatment:

Device: Greifer then Axon-Hook

Axon-Hook then Greifer

Active Comparator group

Description:

T0 + 2 weeks: evaluation with Axon-Hook. T1 + 2 weeks: evaluation with Greifer

Treatment:

Device: Axon-Hook then Greifer