The C-Brace consists of individually fabricated thigh, calf and foot components. An ankle joint, unilateral or bilateral fitting, or an individual spring element connects the foot and calf components. The sensor system continuously measures the flexion of the knee joint and its angular acceleration. This allows the C-Brace to detect the user's current walking phase, so it can regulate the hydraulic resistances as well as control the flexion and extension of the knee joint.

The Timed Walk test is used to measure gait speed on either a 25-foot or 10-meter straight course timed using the middle 10 feet or 6 meters, respectively. Three trials are performed and the average of the three used. Patients are allowed the use of assistive device (such as a cane, crutches or walker) that they normally use for in home or community ambulation.

Originally designed to test mobility skills in the elderly, the TUG is a validated test for quantifying functional mobility and risk of falling. In the TUG Test, patients are asked to stand up from a chair, walk ten feet, turn and return to the chair, and then sit on the chair. For centers routinely using the TUG as a part of their standard of care, this data (time to complete in seconds) will be collected at baseline and follow-up visits when available. Predictive results from the test are as follows: <10s, Freely mobile; < 20s, Mostly independent; 20-29s, Variable mobility.

Assessment of patient-perceived balance confidence for 16 activities of daily living. For each activity, subjects rate their level of confidence in doing the activity without losing their balance or becoming unsteady on a scale from 0% to 100%, with 100% being the highest level of confidence. The total score for the ABC scale is an average of all activity scores.

The PSFS is a self-report measure aimed at identifying functional status limitations that are most relevant to individual patients.The PSFS is a reliable, valid, and efficient measure for detecting clinical change in persons with low back pain and knee dysfunction. Patients will be asked to identify three to five activities that they are having difficulty or are unable to perform because of their injury/condition. For the specified activities, patients will then be asked to rate their ability to perform each activity at that time (0-10 numerical scale) with '0' being unable to perform the activity, and '10' being able to perform the activity at the same level as they could prior to the injury/condition. There is no total score for this measure.

The NPRS is a valid and reliable measure of pain that may be used across all musculoskeletal injuries/conditions and complements the Patient Specific Functional Scale (PSFS). The patient will be asked to rate the pain of their joints, foot, lower back, and if they are using an assistive device any additional affected limbs on average over the last 24 hours on a scale 1-10, with '1' being 'very mild' and '10' being the 'unimaginable unspeakable'. There is no total score for the NPRS.