The purpose of this study is to evaluate of functional tests and clinical findings with APOS System treatment in patient after bi-trimalleolar fracture of ankle. These functional changes will be evaluated AOFS, FAOS, SF36 and WOMAC scores, walking laboratory GAITRite and clinical examination.

Trial design Prospective, comparative, randomize trial. The patients after surgery due to bi or trimalleolar fracture of ankle, that were referred to the physiotherapy treatment, 3 weeks cast and 6 weeks from surgery with full weight bearing indicated by orthopedic

• The population will randomized separated in trail and control group/ Both receive APOS shoes The trial group will receive APOS walking system

• The control group will receive the same walking protocol as the trial group without biomechanics units.

  1. st visit: enrollment of patient - 6 weeks post op 1. The patient will be given a full verbal and written explanation regarding the trial and treatment. The patient will sign the informed consent form and will be given a serial number.

  2. The screening forms will be completed. 3. Demographic data: date of birth, sex, age and complete medical history, height and previous treatments will be recorded.

  4. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF 5. Walking test using a laboratory walking GAITRite + 6 minute walk test 6. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC 7. Adjustment of Apos walking System

  2nd visit: 12 weeks post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF
  2. Walking test using a laboratory walking GAITRite + 6 minute walk test
  3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

  3rd visit: 3 month post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF
  2. Walking test using a laboratory walking GAITRite + 6 minute walk test
  3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

  4th visit: 6 month post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF
  2. Walking test using a laboratory walking GAITRite + 6 minute walk test
  3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

  5th visit: 12 month post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF 2. Walking test using a laboratory walking GAITRite + 6 minute walk test 3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

  6th visit: 18 month post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF
  2. Walking test using a laboratory walking GAITRite + 6 minute walk test
  3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

  7th visit: 24 month post op

  1. Physical examination: range of motion, Achilles tendon thickness. The results will be recorded in the CRF
  2. Walking test using a laboratory walking GAITRite + 6 minute walk test
  3. Fill out questionnaire: FAOS - AOSF - SF36 - WOMAC

Inclusion Criteria:

• Male or female patients 18-65 year old
• Post operation bi- trimalleolar fracture of ankle
• Download cast after 3 weeks
• Full Weight bearing after 6 weeks
• Patients in medical condition to receive physiotherapy treatment
• Patients who are willing to participate in the trial, to come to all scheduled visits and to sign the informed consent forms.

Exclusion Criteria:

• Patients suffering muscular or nerve disorders
• Patients who are unable to use the APOS SYSTEM and can not complete the experimental protocol due to physical or mental handicap
• Non cooperative patient with the basic rehab program.