Advanced prosthetic devices are currently controlled by electromyography (EMG) signals generated by patient's stump muscles and recorded by surface electrodes attached on the skin. This way of recordings is often unreliable, inconsistent and leading to high prosthetic abandonment rates for individuals with upper limb amputation. The use of implantable electrodes has been long thought as the solution for a more natural control of artificial limbs, as these offer access to long-term stable and physiologically appropriate sources of control, as well as the possibility to elicit appropriate sensory feedback via neurostimulation.

This Clinical Investigation (CI) is performed to clinically test and verify the safety and benefits of a bidirectional interface into the human body that allows permanent and reliable communication using implanted electrodes. These electrodes will provide long-term stable bioelectric signals for an improved control of artificial limbs. The bidirectional interface is based, and requires, the clinically established implant system for bone-anchored prostheses named Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA). The feasibility of the device was initially proven through a proof-on-concept patient who has used the system without any adverse events for more than three years.

This CI is performed to verify the safety and benefits of the Osseointegrated Human Machine Gateway (OHMG) as an enhancement of the OPRA Implant System for patients with upper limb amputation, when used within the intended purpose and according to instructions. The CI will be performed at Sahlgrenska University Hospital and Chalmers University of Technology, Sweden. A maximum of eighteen patients will be enrolled. Each patient will undergo a surgery where the OHMG will be implanted. The patients will participate in 8 follow-up sessions, the last one approximately 13 months after the surgery. The study is prospective, where the patient is his/her own control.

Inclusion Criteria:

• The patient is an uni- or bi-lateral, transhumeral or transradial amputee
• At least 2 cm from the joint to the most proximal side of the fixture must be present.
• The patient has at least portion of biceps and triceps muscles present.
• The patient currently has, or has been accepted to have, the OPRA Implant System.
• The patient is younger than 70 and older than 17.
• The patient is willing to participate in all assessment sessions (follow-ups).
• The patient has experience using a surface myoelectric prosthesis.

Exclusion Criteria:

• Patient that has a significant cognitive impairment that prevents her/him from following instructions.
• The patient has any concurrent disease or conditions that might affect the treatment with the OHMG.
• The patient is pregnant.
• The patient is participating in another study.