Magnetic Bead Tracking System and EOPRA Implant System with Bionic Prosthesis for Transtibial Amputees

Inclusion Criteria:

1. Male or Female age 22-65 at the time of surgery.

2. The subject must already have been implanted with the e-OPRA Implant System at thetranstibial level or must have an existing unilateral or bilateral transtibialamputation or a medical condition requiring performance of a unilateral or bilateraltranstibial amputation with a minimum of 8 cm of residual tibia after amputation,such that the subject will be implanted with the e-OPRA Implant System. (OPTION 1)

3. If the subject does not already have the e-OPRA Implant System, the subject musthave undergone independent consultation with at least two lower extremity surgicalspecialists to ensure they have exhausted all limb salvage options prior toundergoing amputation, as well as a psychiatric evaluation to ensure appropriatecapacity and volition. (OPTION 2)

4. The patient must have the ability to ambulate at variable cadence (an expected lowerextremity prosthesis functional level of K3 or above, as confirmed by studyinvestigators).

5. The patient must have adequate soft tissue bulk and muscle mass present in theoperative limb to support appropriate wound healing.

6. In the opinion of the investigator, normal cognitive function and absence of anyphysical limitations, addictive diseases or underlying medical conditions that maypreclude the patient from being a good study candidate.

7. Willingness, ability and commitment to participate in baseline and follow-upevaluations for the full length of the study.

8. Willingness and ability to provide informed consent to participate in the study.

Exclusion Criteria:

1. Subjects with any active skin disease in the tested limb.

2. Subjects with severe co morbidity, atypical skeletal anatomy, or poor generalphysical/mental health that, in the opinion of the Investigator, will not allow thesubject to be a good study candidate (i.e. other disease processes, mental capacity,substance abuse, shortened life. expectancy, vulnerable patient population, BMI >40,etc.).

3. For subjects who have not yet been implanted with the e-OPRA Implant System,subjects who would have less than 2 mm of remaining cortex bone available around theimplant, if implanted.

4. Subjects with advanced atrophic muscle and/or compromised soft tissue coverage inthe operative limb.

5. Subjects with evidence of or a documented history of severe peripheral vasculardisease, diabetes mellitus (type I or type II), skin diseases, neuropathy orneuropathic disease and severe phantom pain, or osteoporosis, such that, in theopinion of the investigator, will not allow the subject to be a good studycandidate.

6. Subjects with a history of systemically administered corticosteroids,immune-suppressive therapy or chemotherapy drugs within six (6) months of implantsurgery.

7. Subjects with a known need of future MRIs.

8. Subjects currently involved in another clinical study where that participation mayconflict or interfere with the treatment, follow-up or results of this clinicalstudy.

9. Active smokers will be excluded from candidacy; those patients willing to undergotobacco cessation will need to be completely abstinent from tobacco use for at least 6 weeks preoperatively.

10. Women who are pregnant, lactating or planning a pregnancy during the first twelve (12) months of the post-surgical follow-up.

11. Subject has an allergy to any component of the device.

12. Concurrent illness, disability or geographical residence would hamper attendance atrequired study visits.