The purpose of this graduate student research study is to determine the effect of various linear and angular prosthetic alignments on K1-K3 unilateral or bilateral TT amputees, as well as test for proficiency, comfort, balance, heart rate and fit during sit to stands.

Initial Visit:

1. Informed consent
2. HIPAA
3. Foot Inspection
4. Review expectations
5. Take measurements
6. Casting

Second Visit: Fitting and adjusting accordingly.

• One person will conduct all the measurements, casting, check sockets, etc. to evade inconsistencies in data collection.
• Begin conducting practice runs on Balance Master at LLU-East Campus.

Third, Fourth and Fifth Visit: Testing (5-10-minute rest period in between each test) *Testing will be video recorded for re-assessment of subjects*

1. Five times sit-to-stand test (5XSTS).

2. Activities-Specific Balance Confidence (ABC-16) scale

3. Balance Master:

   Weight Bearing Squat (WBS) Unilateral Stance (US) Sensory Organization Test (SOT) modified Clinical Test of Sensory Interaction on Balance (mCTSIB) Limits of Stability (LOS)

4. A Polar H10 heart rate monitor will be worn while subjects perform each of the various tests.

Inclusion Criteria:

Male and Female below knee amputees (bi-lateral or unilateral)

• 18-70 years of age

• K1-K3 (K-levels/activity levels)

  • K1=patient has the ability or potential to use a prosthesis for transfers or walking on level surfaces at a fixed speed (typical limited or unlimited household ambulator).
  • K2=patient has the ability or potential for walking with the ability to traverse most low-level environmental barriers such as curbs, stairs, or uneven surfaces (typical community ambulator).
  • K3=patient has the ability or potential for walking with variable speed. Has the ability to traverse most environmental barriers and may have vocational, exercise, or recreational activities that demand prosthetic use beyond simple locomotion.

• Those who wear a prosthesis daily for the purpose of walking

• Able to get in and out of a chair

• Prosthetic foot that has the same functional components as the subject's current one

Exclusion Criteria:

Amputation at birth

• Foot amputation at ankle
• Uncontrolled edema in leg compartments
• Compromised skin of the residual limb
• Patients that are 3 months or less post-amputation

A sock will be placed over the prosthesis in order for the participant to not know which alignment is used.