Clinical UM Guideline

This document addresses the use of a microprocessor controlled knee-ankle-foot orthosis (for example, the C-Brace^® and E-MAG, Ottobock HealthCare LP, Austin, TX; and Neuro HiSwing R+,Össur, Reykjavík, Iceland) that provides support for individuals with lower extremity weakness. This microprocessor controlled device is a stance and swing phase control orthosis (SSCO) intended to augment the function of individuals with peripheral or central neurologic conditions that result in weakness or paresis of the quadriceps and/or other knee extensor muscles.

Note: This device should not be confused with microprocessor controlled prosthetic devices, which are intended to replace or compensate for a missing limb or body part. For documents related to microprocessor controlled prosthetic devices see

• CG-OR-PR-08 Microprocessor Controlled Lower Limb Prosthesis.

Note: Please see the following related document for additional information: 

• CG-OR-PR-13 Ankle-Foot and Knee-Ankle-Foot Orthoses
• CG-OR-PR-12 Lower Limb Prosthesis
• OR-PR.00009 External Lower Extremity Sensory Prosthetic Devices

Note: For a high-level overview of this document, please see “Summary for Members and Families” below. 

Medically Necessary:

1. Microprocessor controlled knee-ankle-foot orthoses are considered medically necessary when all of the following criteria set forth in (A) and (B) below have been met:
   1. Selection criteria:
      1. Individual is ambulatory and use of a knee-ankle-foot orthosis (KAFO) is appropriate; and
      2. Individual has adequate cardiovascular reserve and cognitive learning ability to master the higher level technology; and
      3. The provider has documented that there is a reasonable likelihood of better mobility or stability with the device instead of a KAFO; and
      4. There is documented need for ambulation in situations where the device will provide benefit (for example, regular need to ascend/descend stairs, traverse uneven surfaces or ambulate for long distances [generally 400 yards or greater cumulatively])
         and
   2. Documentation and performance criteria:
      1. Complete multidisciplinary assessment of individual including an evaluation by a certified orthotist. The assessment must objectively document that all of the above selection criteria have been evaluated and met.

Not Medically Necessary:

The use of a microprocessor controlled knee-ankle-foot orthosis is considered not medically necessary when the criteria above have not been met.

This document describes clinical studies and expert recommendations, and explains when microprocessor controlled knee-ankle-foot orthoses are clinically appropriate. The following summary does not replace the medical necessity criteria or other information in this document. The summary may not contain all of the relevant criteria or information. This summary is not medical advice. Please check with your healthcare provider for any advice about your health.

Key Information

A microprocessor controlled knee-ankle-foot orthosis (KAFO) is a leg brace that uses a small computer to help control movement of the knee during walking. These devices are used for people with weakness in the muscles that help straighten the knee, which may be caused by nerve or brain conditions. These devices are designed to improve stability and make walking safer in certain situations. They are different from prosthetic devices, which are meant to replace a missing limb.

What the Studies Show

A microprocessor controlled KAFO provides support during both the standing and walking phases of movement. Such devices use sensors and computer technology to adjust knee movement as a person walks. This may help some people move more safely and confidently, especially when walking on uneven ground, climbing stairs, or walking longer distances.

These devices may offer advantages over a standard non-powered KAFO for some people. Potential benefits include better stability and mobility, and possibly fewer falls and injuries. However, these devices require training to learn how to use them safely and effectively. A person must have the physical ability and thinking skills needed to use the technology. A complete evaluation by a healthcare team, including a certified orthotist, is needed to determine whether the device is likely to help.

When is a Microprocessor Controlled Knee-Ankle-Foot Orthosis Clinically Appropriate?

A microprocessor controlled knee-ankle-foot orthosis may be appropriate in these situations:

• The person is able to walk, and a knee-ankle-foot orthosis is appropriate; and
• The person has enough heart and lung function and the ability to learn how to use the device safely; and
• The healthcare provider has documented that the device is reasonably expected to improve mobility or stability compared with a standard KAFO; and
• The person has a documented need to walk in situations where the device is expected to help, such as climbing or descending stairs, walking on uneven surfaces, or walking long distances, generally 400 yards or more; and
• A complete evaluation by a healthcare team, including a certified orthotist, has been completed and has documented that all of the above criteria have been met.

When is this not Clinically Appropriate?

A microprocessor controlled knee-ankle-foot orthosis is not clinically appropriate when the criteria listed above have not been met. Better studies are needed to know if use outside these criteria improves health. Using devices that have not been shown to help can expose people to inconvenience and device-related risks without clear benefit.

(Return to Description)

The following codes for treatments and procedures applicable to this guideline are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

When services are Not Medically Necessary:
For the procedure code listed above when criteria are not met.

Summary

More than 1.8 million individuals in the U.S. use lower-extremity orthoses, with traditional devices like locked knee-ankle-foot orthoses (LKAFOs) historically prescribed for quadriceps weakness. However, these often lead to abnormal gait patterns, pain, and reduced mobility. More recent innovations such as stance-controlled orthoses improve swing-phase knee flexion but remain limited in adaptability and function, particularly on uneven terrain. In contrast, microprocessor-controlled orthoses, such as the C-Brace, are proposed to offer dynamic knee control through advanced sensor technology that adjusts knee stability and swing in real time. This hydraulic-electronic system is proposed to enable a more physiological gait, support a wider range of motion, and mimic quadriceps function. Multiple clinical trials and studies, including RCTs and multicenter registries, have reported that C-Brace use leads to statistically significant improvements in gait speed, balance, stair navigation, fall reduction, and quality of life (QoL). While data from sources such as Deems-Dluhy (2021), Genêt (2026), Pröbsting (2017), Schmalz (2016), Ruetz (2024), and Lundstrom (2024) consistently demonstrate functional and psychosocial benefits over standard KAFOs, generalization of results is limited by the poor quality of this evidence, with factors such as high dropout rates, lack of control groups, and small sample sizes. Additional data from robust, well-designed and conducted trials is needed to determine the clinical utility of microprocessor-controlled orthoses in the general population.

Discussion

More than 1.8 million people in the United States use lower-extremity orthoses. For centuries, individuals with lower-extremity weakness, or specifically quadricep weakness, were prescribed an LKAFO. This device may cause abnormal gait patterns that can contribute to chronic pain, slower gait and decreased mobility (Deems-Dluhy, 2021). Since 1978, SCOs that allow users to flex their knee during the swing phase to prevent abnormal gait patterns have been another option to individuals who suffer from lower limb paresis or paralysis (Pröbsting, 2017). Devices such as LKAFOs and SCOs are limited in function whereas a myoelectric orthosis, such as the C-Brace, uses sensor technology to improve the balance, functional mobility and QoL in individuals with lower-extremity impairments. The C-Brace combines electronic components with a specialized orthotic brace that provides support for individuals with conditions such as lesions of the femoral nerve, incomplete spinal cord injury, as well as orthopedic conditions that result in uncontrolled knee flexion, failed knee joint replacement and knee joint derangement. The C-Brace’s stance and swing phase of the gait cycle is controlled hydraulically with microprocessor sensor technology that receives information from the electronic sensors 100 times per second. This device stabilizes the knee in the sagittal plane and mimics the physiologic function of the quadriceps muscle which supports the user during the entire gait cycle. With the use of this microprocessor-controlled leg orthotic, an individual is able to obtain a closer physiological value of walking compared to the functionality of conventional paralysis orthoses that are limited to releasing and locking the knee joint.

The lack of functional ability of individuals with conditions that result in weakness or paresis of the quadriceps and/or other knee extensor muscles can have a significant impact on ADLs. The Manual muscle testing (MMT) Grading system is used by practitioners for the evaluation of strength of individual muscles or muscle groups. This grading system has a scale of 0 to 5 and the purpose of this grading system is to ensure accurate, consistent interpretation of MMT findings. The following classifications are used to determine strength and grade:

Level 0:     No visible or palpable contraction
Level 1:     Palpable muscle contraction but no joint movement, gravity eliminated
Level 1+:    Less than or equal to half active range with gravity eliminated
Level 2-:     Movement greater than half range but less than full range, gravity eliminated
Level 2:      Full range of motion (ROM), gravity eliminated, cannot take resistance nor initiate against gravity
Level 2+:    Completes less than or equal to half range actively against gravity and completes full ROM with gravity eliminated
Level 3-:     Greater than half range but less than full range in antigravity position
Level 3:      Full ROM, antigravity, cannot take resistance
Level 3+:    Full ROM against gravity with slight resistance
Level 4-:     Full ROM against gravity with mild resistance
Level 4:      Full ROM against gravity with moderate resistance
Level 4+:    Full ROM against gravity with slightly greater than moderate resistance
Level 5:      Normal, maximal resistance

According to the U.S. Food and Drug Administration (FDA), the C-Brace is classified as a Class I device and exempt from the premarket notification 510(k) requirements as well as the Medical Device Good Manufacturing Practices (GMPs). A device may be exempt from 510(k) requirements if the FDA determines that a 510(k) is not required to provide reasonable assurance of safety and effectiveness for the device (FDA, 2019).

Traditionally, individuals who require the use of an orthosis due to a condition that results in weakness or paresis of the lower extremity have been prescribed and fitted with other types of orthoses such as an LKAFO or an SCO. The C-Brace and similar devices utilize microprocessor-controlled hydraulic units to potentially provide stability and dynamic movement improvements to leg orthosis-dependent individuals.

Individuals with lower limb weakness or paralysis may benefit from the use of a KAFO. There are different types of KAFOs and the mechanism of action of the KAFO that is prescribed depends on the individual’s need and the remaining muscle function (Pröbsting, 2017). A stance controlled orthosis (SCO) is a form of KAFO which uses various technical switching mechanisms to allow locking the orthotic knee joint during stance for safe standing and walking as well as unlocking it at the end of the stance. Although this type of device allows an individual to flex their knee during the gait cycle, it is has been reported to be limited in function and safety due to its inconsistent control of the stance knee on stairs, ramps and uneven ground (Deems-Dluhy, 2021). The C-Brace, which uses signal-processing algorithms, supports walking with a wide variety of different gait velocities. This type of orthosis may be appropriate for individuals who meet specific criteria for fitness, health, and daily utilization expectations. According to the manufacturer, there are prerequisites that an individual must meet before an individual can be considered a candidate for the C-Brace: able to fully stabilize their trunk and to stand when knee flexion is locked, hip extensor and flexor strength available to permit the controlled swing-through of the affected leg, or the ability to advance the limb by compensatory trunk movement in the absence of such strength, and body weight of 275 pounds or less. Unlike the KAFO and SCO, the C-Brace controls knee flexion during weight bearing and dynamic swing control (Pröbsting, 2017).

Pröbsting and others (2017) reported the results of a study to evaluate the potential benefits of a C-Brace compared to SCO and LKAFO in activities of daily living (ADL). The study design was a survey of 13 lower limb orthosis users before and after fitting of a C-Brace. All participants were dependent on KAFOs. Only 1 participant needed orthoses for both legs. Inclusion criterion was that individuals had to have used their previous orthosis for at least 6 months prior to enrollment in this study. Based on the results of the self-reported Orthosis Evaluation Questionnaire and the Activities of Daily Living Questionnaire (ADL-Q), participants rated the activities in the domains of family and social life (p=0.01) and mobility and transportation (p=0.002) significantly easier to perform with the C-Brace compared to their standard device. In the categories sports (p=0.02) and ‘other activities’ (p=0.03), a significant improvement with the C-Brace was reported compared to their standard device. No significant difference was seen in the domain personal hygiene and dressing. In the subgroup of participants who had previously used SCOs, use of a C-Brace resulted in a significant improvement in the category of mobility and transportation (p=0.02). Similarly, in the subgroup of participants who had previously used LKAFOs, significant improvements were reported post-C-Brace use in the categories family and social life (p=0.04), mobility and transportation (p=0.04), and other activities (p=0.04). Perceived comparative safety was reported as improved by 59% of subjects with the microprocessor controlled orthoses compared to a standard device. The authors concluded that the C-Brace may facilitate an easier, more physiological, and safer execution of many ADLs compared to traditional leg orthosis technologies.

Deems-Dluhy (2021) evaluated the potential of the C-Brace compared to an SCO and conventional KAFO over a period of a month. This randomized controlled trial (RCT) included 18 participants who actively used a unilateral KAFO and used the following inclusion criteria: 18-80 years of age, regular and compliant use of a unilateral KAFO or SCO for impairment due to neurologic or neuromuscular disease, orthopedic disease, or trauma, ability to demonstrate a gait pattern to use the SCO and C-Brace, cognitive ability to understand and willingness to provide informed consent and follow the study protocol. Exclusion criteria included participants with ankle passive range of motion less than two degrees or knee flexion contracture or alignment resulting in the inability to actively use the study device, weight greater than 275 pounds, unstable neurologic or cardiovascular or pulmonary disease, or cancer, and participation in physical therapy specific to orthotic and gait training within 1 month of enrollment. Significant changes were observed in participants’ self-selected gait speed (p=0.023), Berg Balance Scale (BBS) results (p=0.01), Functional Gait Assessment (FGA, p=0.002), and Stair Assessment Index (SAI, p<0.001) between baseline and post-C-Brace assessment. Similar significant differences were seen when comparing post- C-Brace with post-SCO data. During the 6-minute walk test (6MWT), persons using the C-Brace walked significantly longer (p=0.013) than when using their baseline device. Participants reported higher QoL life scores in the Orthotic and Prosthetic User’s Survey (OPUS) (p=0.02) and physical health domain of the World Health Organization Quality of Life (WHOQOL)-BREF (p=0.037) after using the C-Brace. Participants reported fewer falls when wearing the C-Brace compared to an SCO or locked knee-ankle-foot orthosis (LKAFO). The study concluded that the C-Brace may contribute to improved QoL and health status of individuals with lower extremity impairments by providing the ability to have better walking speed, endurance, and functional balance.

Ruetz (2024) reported the results of a randomized, controlled, cross-over clinical trial involving 102 experienced KAFO users at risk of falling who were assigned to 3 months using either a standard KAFO or the C-Brace before switching devices for an additional 3-month trial. Inclusion criteria were > 18 years of age, at least 3 months of uni- or bilateral KAFO use, Berg Balance Scale (BBS) score < 45, minimum hip strength of grade 3 for bilateral users or the ability to swing the orthotic leg forward with trunk movement, potential to use the C-Brace successfully, ability to recognize low battery indicators from the device, and commitment to use the C-Brace for a minimum of 1-2 hrs./5 days a week. Exclusion criteria were, no prior use of a lower limb orthosis, prior use of a C-Brace, weight > 125 kg, lower limb amputation, hip or knee contracture > 10°, bowed legs or knock knees > 10° that cannot be corrected, uncontrolled moderate to severe spasticity, limb length discrepancy > 15 cm, known vertigo, or history of falls. A total of 69 participants (67.6%) completed the full trial and were included in the per-protocol (PP) analysis. The intent-to-treat (ITT) analysis included the full 102 participants. After a 3-month trial, BBS results indicated a significant improvement with the C-Brace compared to the standard device group in both the PP and ITT analyses (p<0.00001 for ITT and p<0.00006 for PP). Similar findings were reported for falls (p<0.002 for ITT and p<0.0005 for PP), Dynamic Gait index (DGI, p<0.005 for ITT and p<0.00001 for PP), Activity-specific Balance Confidence (ABC, p<0.005 for ITT and p<0.0001 for PP), and SAI (p<0.006 for ITT and p<0.008 for PP). Results were significantly improved in the C-Brace compared to the standard device group in the ITT but not the PP analysis in several measures, including the OPUS Lower Extremity Functional Status score (p<0.00019 for ITT and p<0.06 for PP) and the Reintegration into Normal living index (RNLI, p<0.08 for ITT and p<0.042 for PP). The opposite was found for the WLQ-25 Physical (p<0.281 for ITT and p<0.039 for PP) and the EQ-5D5L Utility (p<0.15 for ITT and p<0.037 for PP). No differences between groups were reported for the 6MWT (p<0.58 for ITT and p<0.55 for PP). The authors concluded that the C-Brace provided significant benefits over standard KAFO devices with regard to falls and overall mobility.

Lundstrom (2024) reported the results of an analysis of 91 individuals fitted with the C-Brace device enrolled in a prospective international, multicenter registry and followed for at least 1 year. Baseline data was collection with the participants existing orthosis or current ambulatory condition in the clinic. Primary outcome measures included 10-meter Walk Test (10MWT) or 25-foot Walk Test to assess self-selected walking speed and fastest possible walking speed (FWS), walking ability as measured by the Timed Up and Go (TUG) test, and patient-perceived balance confidence as measured by the ABC test. Secondary outcomes measures were the Patient-Specific Functional Scale (PSFS), daily step counts as measured by a FitBit for 2 weeks- following each visit, and the BBS. As of the cutoff date, 12 of the original 91 participants had follow-ups not yet due, 21 had dropped out, 11 had missing follow-up visits, and one had missing baseline data. Thus, the 1-year report included 46 (47%) total participants for analysis. Performance measures at both baseline and follow-up were available for 40 (44%) participants. FWS was reported to have significantly increased between baseline and 1-year with the average speed at follow-up nearly reaching 1 m/s (0.26 m/s, p<0.0001). At follow-up, 16 participants (40%) moved up at least one ambulation level (e.g., from household ambulators to limited community ambulators or community ambulators). TUG times significantly improved, decreasing by 8.1 seconds (p<0.0001). At baseline, 32 participants (80%) had TUG times > 13.5 sec, indicating an increased risk of falling. At follow-up, only 17 (43%) were in this category. Similarly, mean ABC score significantly increased between baseline and 1-year (24.9 %, p<0.0001). Based on this data, 35 participants (76.1%) were at risk of falling at baseline and only 19 (41.3%) were at risk of falling at 1 year. The authors noted that “using Hochberg’s method, the highest p-value for the three primary endpoints evaluated as a family was for the TUG. Since this p-value was <0.05, all null hypotheses were rejected…” For PSFS, 33 participants (36.3%) had both baseline and follow-up data available. The average PSFS score was reported to have more than doubled from 2.1 at baseline to 5.7 at follow-up, an average improvement of 3.6 (p<0.0001). Fall data was available for 42 (46.2%) participants, which indicated a reduction in the average number of falls in the previous 6 months of 91%, with the median falling from 3 to 1. The authors concluded that their study found the clinical improvements in fast walking speed, walking capability, and patient-perceived balance confidence, risk of falling, and actual falls. However, the significant loss to follow-up, lack of control group, and blinding make generalization of these results difficult.

In 2023, Raijmakers reported the results of a prospective study involving a convenience sample of 10 participants with lower limb weakness of neuromuscular etiology comparing two different microprocessor stance control orthoses. Participants were all active users of the E-MAG Active Knee Joint System who were provided a Neuro Tronic as the experimental treatment. Baseline measures were taken with the E-Mag device and then at 4 and 12 weeks after use of the Neuro Tronic device. Outcomes measures included knee joint locking failures and unlocking failures (ULFs) when walking under challenging conditions on an instrumented treadmill, net energy cost (EC, J/kg per meter), 6-MWTm, 3D gait kinematics and kinetics, and patient-reported outcomes. The final report included data from 9 participants due to one COVID-19-related withdrawal. The authors reported no significant differences between groups with regard to knee function (p=0.406), EC (p=0.123), spatiotemporal parameters (p≥0.148), and ankle and knee and hip kinematics (p≥0.084). On the other hand, mean comfortable treadmill speed increased significantly with the Neuro Tronic device, from 0.59 m/s at baseline with the E-MAG to 0.70 m/s with the Neuro Tronic (+19%, p=0.029). Maximal ankle power in terminal stance was reported to have increased significantly with the Neuro Tronic device compared to the E-MAG (0.77 [0.32] W/kg vs. 0.35 [0.12] W/kg, p=0.003). Frontal knee moment during single stance improved in the Neuro Tronic group compared to the E-MAG, decreasing to 0.23 Nm/kg from 0.31 Nm/kg at baseline (p=0.008). Perceived walking effort was reported to have improved significantly with the Neuro Tronic, to 4.0 compared to 3.0 at baseline (p=0.014). Self-reported falls were significantly lower in the Neuro Tronic group (p=0.034). No other significant differences were reported between groups with regard to self-reported measures. The results of this study indicate some possible differences between microprocessor active stance control orthoses, although the small sample and other methodological issues limit the applicability of these findings.

In 2025, Yun reported the results of a prospective study involving 15 participants with post-stroke functional impairment who underwent six supervised over-ground training sessions over three weeks (40 minutes per session) using a device not available in the U.S. (Hexar Humancare Co., Ltd. Ansan, Korea). Pre-specified outcome measures included the BBS, Dynamic Gait Index (DGI), TUG, 6MWT, 10MWT, assessed with and without the device. The authors reported significant improvements for some primary outcomes, including BBS scores (from 45 to 48, p=0.002), DGI scores (from 19 to 21, p=0.004), and TUGT (from 16.80 seconds to 14.82 seconds, p=0.014). For the 10MWT, improvements were seen in distance walked (from 194.1 m to 220.0, p=0.006), walking time (from 8.69s to 6.96s, p=0.008), and gait speed (from 0.57 m/s to 0.71 m/s, p=0.005). No significant differences were reported for the 6mWT (p=0.088), or for pulmonary function, body composition, and spasticity. Participant satisfaction was mixed, with 60% satisfied with use of the device, but 80% preferred their prior gait assist methods, primarily due to device weight, donning/doffing burden, and operational difficulty.

In 2026, Genêt reported the results of a randomized crossover trial involving 38 participants who were community ambulators with quadriceps insufficiency due to neuromuscular or neurological disease. Participants were active users of the E-MAG device and provided 7 training sessions in the use of C-Brace devices. Measurements were taken at the end of 2 to 3 months of regular use periods, with a 2 week transition period between the two. The primary outcome measure was PLUS-M™ 12-item self-reported mobility questionnaire score. Additional measures included 6MWT, and several self-reported measures, including the EuroQol - 5 Dimensions (EQ-5D-L) QoL, the Activities-specific Balance Confidence (ABC-s) scale, the Patient-Specific Functional Scale (PSFS), the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0), and the Psychosocial Impact of Assistive Devices Scale (PIADS). A total of 30 (78.39%) participants successfully completed the trial, with 37 included in the Intent-to-Treat (ITT) analysis and 30 in the Per-Protocol (PP) analysis. Significant differences were reported in the duration of the transition period between devices, with a duration of 15 days between the C-Brace to E-MAG transition and 34 days between the E-MAG to C-Brace Transitions. The delays were attributed to C-Brace orthoses fabrication. With the exception of the PIADS, significant improvements in favor of the C-Brace group were reported for all measures (p<0.001 for all). No significant changes were reported for indoor use of walking aids, but there was a significant decrease in the need for walking aids for outdoor activities with the C-Brace (p=0.005). Overall, 30% of participants did not require walking aids with the C-Brace. A total of 29 adverse events (AEs) occurred in 16 participants, with 10 on the E-Mag group (35 %) and 19 in the C-Brace group (66 %). No description of the events was provided in the full-text version of the study, which refers the reader to an appendix that was not available. The results of this study indicate significant self-reported benefits to the use of a full leg microprocessor controlled lower limb prosthesis compared to stance-only microprocessor controlled lower limb prosthesis. However, methodological flaws such as small sample size, lack of blinding and objective measures limit the utility of these results.

Based on the peer-reviewed literature, use of the microprocessor controlled knee-ankle-foot orthoses has been shown to provide carefully selected individuals better walking speeds, endurance and functional balance with the device as compared to a standard KAFO device. Due to technological advancements of leg orthoses, individuals with lower extremity impairment may have easier execution of many ADLs and achieve improved QoL.

Knee Ankle Foot Orthosis (KAFO): A long-leg orthosis that spans the entire leg and is provided to compensate for muscle weakness, paralysis, or skeletal problems which cause lower limb instability.

Locked Knee Ankle Foot Orthosis (LKAFO): Knee-ankle-foot-orthosis with a locked orthotic knee joint.

Manual Muscle Test (MMT): A procedure for the evaluation of strength of individual muscles or muscle groups, based upon the effective performance of a movement in relation to the forces of gravity or Manual Resistance through the available Range of Motion (ROM).

Orthosis: An orthopedic appliance or apparatus used to support, align, prevent, or correct deformities, or to improve function of movable parts of the body. These types of devices are not prosthetic devices, which are intended to replace or compensate for a missing limb or other body part.

Stance Control Orthosis (SCOs): An orthosis which uses various technical switching mechanisms to allow locking the orthotic knee joint during stance for safe standing and walking as well as unlocking it at the end of the stance phase to allow for a free swing phase.

Peer Reviewed Publications:

1. Deems-Dluhy S, Hoppe-Ludwig S, Mummidisettty CK, et al. Microprocessor controlled knee ankle foot orthosis (KAFO) vs stance control vs locked KAFO. Arch Phys Med Rehabil. 2021; 102(2):233-234.
2. Genêt F, Ruetz A, Belmahfoud R, et al. Impact of a microprocessor-controlled knee-ankle-foot orthosis in community ambulators with quadriceps insufficiency fitted with an SCO: a randomized crossover trial. Ann Phys Rehabil Med. 2026; 69(1):102057.
3. Lundstrom RL, Klenow TD, Morris A, et al. The C-Brace^® microprocessor controlled stance and swing orthosis improves safety, mobility, and quality of life at one year: interim results from a prospective registry. J Rehabil Assist Technol Eng. 2024; 11:20556683241269539.
4. Pröbsting E, Kannenberg A, Zacharias B. Safety and walking ability of KAFO users with the C-Brace^® Orthotronic Mobility System, a new microprocessor stance and swing control orthosis. Prosthet Orthot Int. 2017; 41(1):65-77.
5. Raijmakers B, Brehm MA, Nollet F, Koopman FS. Safety, walking ability, and satisfaction outcomes of the NEURO TRONIC stance-control knee-ankle-foot orthosis (SCKAFO): a comparative evaluation to the E-MAG active SCKAFO. Prosthet Orthot Int. 2024; 48(1):30-38.
6. Ruetz A, DiBello T, Toelle C, et al. A microprocessor stance and swing control orthosis improves balance, risk of falling, mobility, function, and quality of life of individuals dependent on a knee-ankle-foot orthosis for ambulation. Disabil Rehabil. 2024; 46(17):4019-4032.
7. Schmalz T, Pröbsting E, Auberger R, et al. A functional comparison of conventional knee-ankle-foot orthoses and a microprocessor-controlled leg orthosis system based on biomechanical parameters. 2016; 40(2):277-286.
8. Yun YJ, Kim BK, Cho H, et al. Clinical usability and functional outcomes of a lightweight robotic orthosis (HKAFO) in chronic stroke patients with hemiplegic gait: a pilot study. J Neuroeng Rehabil. 2025; 22(1):249.

Government Agency, Medical Society, and Other Authoritative Publications:

1. Centers for Disease Control and Prevention. National health survey. Number of persons using assistive technology devices. Page last reviewed: November 6, 2015. Available at: https://archive.cdc.gov/#/details?url=https://www.cdc.gov/nchs/nhis/ad292tb1.htm. Accessed on August 4, 2026.
2. Mendes LA, Lima IN, Souza T, et al. Motor neuroprosthesis for promoting recovery of function after stroke. Cochrane Database Syst Rev. 2020 Jan 14;1(1):CD012991.
3. U.S. Food and Drug Administration. Class I/II exemptions. Content current as of July 1, 2025. Available at: https://www.fda.gov/medical-devices/classify-your-medical-device/class-i-ii-exemptions. Accessed on August 4, 2024.

Agilik™ smart orthosis
E-Mag Active Knee Joint System
C-Brace
Neuro HiTronic
Neuro Tronic
Neuro HiSwing R+
Microprocessor Controlled Lower Limb Orthosis
Össur
Ottobock

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.

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