Improvement of walking ability during postoperative rehabilitation with the hybrid assistive limb after total knee arthroplasty: A randomized controlled study

Postoperative Rehabilitation Interventions in Patients at Risk of Poorer Outcomes Following Total Knee Arthroplasty: A Systematic Review

PURPOSE

This systematic review evaluated the efficacy of postoperative rehabilitation for patients at risk of poorer outcomes after total knee arthroplasty.

METHODS

Six databases were searched, and only randomised controlled trials were included. Two reviewers independently screened, extracted data, and appraised the quality of the studies.

RESULTS

Twenty-three studies were included. Insufficient evidence supports cognitive behavioural therapy for patients with kinesiophobia, while continuous passive motion may not be effective for range of motion deficits. The impact of exercise therapy on functional recovery is conflicting; however, longer durations tend to be more effective for older patients and those with functional limitations. Limited evidence suggests that exercise may not alleviate pain. Outpatient exercise therapy improves health-related quality of life more than home-based programs for older patients and those with functional limitations. The efficacy of other rehabilitation aspects remains inconclusive due to high heterogeneity in interventions and outcome measures, and high or unclear risk of bias in most studies.

CONCLUSION

While limited evidence suggests benefits for specific rehabilitation interventions, there is insufficient data to assess the efficacy of most interventions on postoperative recovery in those at risk of poorer outcomes. More robust evidence is needed to guide clinical practice and standardise outcome measures.

TRAIL REGISTRATION

PROSPERO CRD42022355574.

Early implementation of MAK robotic device in total knee arthroplasty rehabilitation: A proof-of-concept study

BACKGROUND

Effective rehabilitation following total knee arthroplasty (TKA) is crucial for enhancing both range of motion (ROM) and functional outcomes. While robotics has demonstrated its potential in various medical contexts, the evidence on its application in TKA rehabilitation is still scarce. The marsi active knee (MAK), a robotic device that has already proven to be safe and beneficial in people with neurological disease, has been tested to facilitate the rehabilitation of TKA patients.

OBJECTIVE

This study aims to evaluate the safety, patient satisfaction, and clinical impact of integrating the MAK into an early rehabilitation regimen for TKA patients.

METHODS

The intervention comprised 14 one-hour sessions administered thrice a week, utilizing the MAK within 48 h post-TKA surgery. The rehabilitation sessions incorporated exercises involving passive mobilizations, sit-to-stand transitions, and gait training. Comprehensive data encompassing safety parameters, patient satisfaction, and clinical outcomes were meticulously collected and analyzed.

RESULTS

Six participants successfully completed the rehabilitation protocol with the MAK device. Notably, no significant adverse events were documented. Application of the device corresponded to perceptible reductions in self-reported pain levels. Vital signs remained within minimal variance pre- and post-rehabilitation. Participants proficiently engaged in all assisted exercises facilitated by the device, culminating in a high overall satisfaction rating of 4.6 ± 0.5 out of 5.

CONCLUSION

The findings indicate that the MAK device exhibits a commendable level of safety while obtaining considerable patient satisfaction during the early rehabilitation phase following TKA, suggesting this device may be a reliable adjunct to TKA protocols.

Robotic exoskeletons and total knee arthroplasty: The future of knee rehabilitation and replacement - A meta-analysis

OBJECTIVE

Exoskeletons can play a crucial role in post-TKA rehabilitation by accelerating recovery, improving mobility, and reducing further injury risk. This meta-analysis evaluated the effectiveness of exoskeletons in post-total knee replacement (TKR) rehabilitation.

DESIGN

Comprehensive searches were conducted on PubMed, OVID Medline, Cochrane Collaboration Library, and Embase (period: database inception to March 2023). Randomized controlled trials enrolling patients who underwent TKR and studies examining the effect of robot-assisted rehabilitation on physical function and pain outcomes were eligible for inclusion. Eight studies (302 patients) were thus included.

RESULTS

Exoskeletons significantly improved active range of motion (ROM) (SMD: 10.98, 95% confidence interval (CI): 7.81-14.16, P < .001), passive ROM (SMD: 4.11, 95% CI: 1.02-7.20, P = .009), Hospital for Special Surgery scores (SMD: 7.78, 95% CI: 5.87-9.68, P < .00001), and hospital stay length (SMD: -3.19, 95% CI: -4 to -2.38, P < .00001) compared with conventional rehabilitation. Active and passive ROM improvements suggest that exoskeletons aid knee function restoration and mobility post-TKR, whereas Hospital for Special Surgery score improvements support exoskeleton use in TKR rehabilitation. A shorter hospital stay was an important finding which could potentially reduce healthcare costs and improve outcomes.

CONCLUSION

Despite the inclusion of a limited number of studies, our findings suggest that exoskeletons can enhance post-TKR rehabilitation outcomes and improve quality of life. Robot-assisted rehabilitation may be effective following TKR. Further research should confirm these findings.

Hip Exoskeleton Based Indirect Intervention Strategy Towards Gait Training After Total Knee Arthroplasty

Total Knee Arthroplasty (TKA) is the most effective approach for function restoration in patients with severe knee osteoarthritis. However, kinematic, kinetic and muscle activation differences between post-TKA patients and healthy people can be observed in many studies. Exoskeletons have been applied to post-TKA rehabilitation for many years, while few studies concentrated on the stance phase abnormality, neither in the aspect of kinematics nor in muscle activation. In this paper, we propose an indirect resistance strategy for post-operative TKA patient gait training. Three healthy subjects were asked to wear the hip exoskeleton and provided with 8 N·m resistance on the hip extension phase of the gait cycle. The intervention leads to an increment in the knee extension muscle activity as well as the augmentation in maximum knee angle in loading response. The results indicated that the application of resistance in the hip extension phase is a potential therapeutic approach for post-TKA rehabilitation, and may increase the gait training efficiency in the near future.

[Digital tools in musculoskeletal rehabilitation]

The demographic transition in combination with the increasing demands of society and a growing shortage of skilled workers are leading to a shortage of care in musculoskeletal rehabilitation, especially in times of the pandemic. Digital interventions represent an opportunity to reintegrate patients with musculoskeletal dysfunctions into everyday life. The changes to the legal basis enable physicians and therapists to support the rehabilitation of their patients with reimbursable apps and digital applications and to permanently integrate learned skills into their daily lives. Telerehabilitation technologies, apps, telerobotics and mixed reality offer the opportunity to complement and optimize existing care structures and to redesign specialized therapeutic home visits with modern technology in a new and contemporary way.

[New technologies and robotics]

The development of increasingly more complex computer and electromotor technologies enables the increasing use and expansion of robot-assisted systems in trauma surgery rehabilitation; however, the currently available devices are rarely comprehensively applied but are often used within pilot projects and studies. Different technological approaches, such as exoskeletal systems, functional electrical stimulation, soft robotics, neurorobotics and brain-machine interfaces are used and combined to read and process the communication between, e.g., residual musculature or brain waves, to transfer them to the executing device and to enable the desired execution.Currently, the greatest amount of evidence exists for the use of exoskeletal systems with different modes of action in the context of gait and stance rehabilitation in paraplegic patients; however, their use also plays a role in the rehabilitation of fractures close to the hip joint and endoprosthetic care. So-called single joint systems are also being tested in the rehabilitation of functionally impaired extremities, e.g., after knee prosthesis implantation. At this point, however, the current data situation is still too limited to be able to make a clear statement about the use of these technologies in the trauma surgery "core business" of rehabilitation after fractures and other joint injuries.For rehabilitation after limb amputation, in addition to the further development of myoelectric prostheses, the current development of "sentient" prostheses is of great interest. The use of 3D printing also plays a role in the production of individualized devices.Due to the current progress of artificial intelligence in all fields, ground-breaking further developments and widespread application possibilities in the rehabilitation of trauma patients are to be expected.

Robot-assisted rehabilitation for total knee or hip replacement surgery patients: A systematic review and meta-analysis

BACKGROUND

This study was performed to update the current evidence and evaluate the effects of robot-assisted rehabilitation (RAR) in comparison with conventional rehabilitation (CR) in patients following total knee (TKR) or hip replacements (THR).

METHODS

PubMed Central, OVID Medline, Cochrane Collaboration Library, and EMBASE for a comprehensive search for all relevant studies, from database inception to July 2022. The following inclusion criteria were used to determine eligibility for studies: randomized and matched controlled trials recruiting men and women who underwent TKR and THR; and studies examining the effect of RAR on outcome measures of physical function and pain.

RESULTS

A total of 9 studies (230 patients) were included in this review and 4 were included in the meta-analysis. The meta-analysis of 2 studies showed that Hybrid Assistive Limb (HAL) training for 5 days, significantly improved pain measured on a visual analogue scale, compared to CR in patients following TKR (SMD = 1.05, 95% confidence interval [Cl] 0.39-1.71). Heterogeneity for I2 value was lower than moderate (tau^2 = 0.0121; I2 = 5%; P = .30). There were 2 studies that assessed self-selected walking speed. The meta-analysis of these studies showed that HAL training was significantly superior to CR in patients following TKR (SMD = 48.70, 95% Cl -50.53 to 147.94) at 2 months. A high heterogeneity was detected (P < .01; I2 = 97%).

CONCLUSION

The result of this systematic review and meta-analysis suggest that RAR may be an effective treatment in TKR and THR patients. However, high-quality studies are needed to verify the long-term effect on their recovery.

Biofeedback Physical Therapy With the Hybrid Assistive Limb (HAL) Lumbar Type for Chronic Low Back Pain: A Pilot Study

Objective

There are many treatments for chronic low back pain, including various medications, exercise therapy, orthotics, and surgery, but no treatment is definitive. We hypothesized that biofeedback therapy using the hybrid assistive limb (HAL) lumbar type would have some immediate effects on chronic low back pain. The purpose of this pilot study was to assess whether immediate changes in low back pain and hip flexibility and any other adverse events would occur following the HAL biofeedback physical therapy.

Methods

This was a single-center, pilot, prospective, single-arm study of outpatient biofeedback physical therapy using the HAL lumbar type for patients with chronic low back pain. Patients underwent a 10-minute biofeedback physical therapy (lumbar flexion-extension, sit-to-stand, and squat) with the HAL lumbar type (in one session). The visual analog scale (VAS) score of low back pain during lumbar flexion, extension, lateral bending, and rotation was evaluated. The finger-to-floor distance (FFD), straight leg raising test (SLR), and the Thomas test were measured to assess hip flexibility.

Results

All 35 participants (14 men and 21 women) (100%) conducted a biofeedback HAL therapy session using the HAL lumbar type. No participant had deterioration of low back pain. No adverse events occurred. After the biofeedback therapy using the HAL lumbar type, SLR demonstrated a significant positive change with large effect size and sufficient power. Lumbar VAS during lumbar flexion and extension and FFD showed a significant positive change with medium effect size and adequate power.

Conclusions

Biofeedback therapy using the HAL lumbar type is an option for intervention in chronic low back pain.

Early Postoperative Rehabilitation Using the Hybrid Assistive Limb (HAL) Lumbar Type in Patients With Hip Fracture: A Pilot Study

Objective: To extend life expectancy after surgery, patients with hip fractures need to improve their mobility quickly through postoperative rehabilitation. Voluntary hip joint motion supported by the hybrid assistive limb (HAL) lumbar type, an exoskeleton robot suit characterized by its ability to detect the wearer’s intentions through the bioelectrical signals and assist hip extension motions at an optimal timing, may be effective to improve mobility in patients with hip joint dysfunction after surgery. We aimed to introduce rehabilitation using the HAL lumbar type in the early period after hip fracture surgery.

Methods: Patients who underwent internal fixation for hip fracture at a single institution were prospectively enrolled. They received early postoperative rehabilitation (forward and backward bending of the lumbar spine, pelvic tilt forward and backward, standing up, and squatting) using the HAL lumbar type (six times a week for 15 min per session). Five-times-sit-to-stand (FTSS) and timed-up-and-go (TUG) tests were conducted at baseline before HAL rehabilitation (pre-HAL) and after the HAL rehabilitation (post-HAL) intervention.

Results: We enrolled 14 patients (one man, 13 women) in this study. There were no adverse events, and all patients were able to complete the entire rehabilitation program. Post-HAL FTSS showed significant improvement compared with pre-HAL and had a large effect size of 1.81 (95% CI = 0.93 to 2.66) and sufficient power.

Conclusions: Robotic rehabilitation with HAL lumbar type could be introduced without adverse events, even in the early postoperative period following surgery for hip fracture. Further study is needed to develop an appropriate rehabilitation protocol using the HAL lumbar type.

Reporting of post-operative rehabilitation interventions for Total knee arthroplasty: a scoping review

OBJECTIVE

The aim of this study was to evaluate the completeness of reporting of exercise adherence and exercise interventions delivered as part of clinical trials of post-operative total knee replacement (TKA) rehabilitation.

DESIGN

Scoping review LITERATURE SEARCH: A literature search was conducted in PubMed, EMBASE, AMED, CINAHL, SPORTDiscus and Cochrane Library.

STUDY SELECTION CRITERIA

All randomized controlled trials (RCT) that examined post-operative exercise-based interventions for total knee arthroplasty were eligible for inclusion. Studies that were multifactorial or contained exercise interventions for both hip and knee arthroplasty were also included.

DATA SYNTHESIS

The definition, type of measurement used and outcome for exercise adherence were collected and analyzed descreptively. Quality of reporting of exercise interventions were assessed using the Consensus for Exercise Reporting Tool (CERT) and the Cochrane Risk of Bias Tool.

RESULTS

There were a total of 112 RCTs included in this review. The majority of RCTs (63%, n = 71) did not report exercise adherence. Only 23% (n = 15) of studies provided a definition of adherence. RCTs were of poor quality, with 85% (n = 95) of studies having high or unclear risk of bias. Reporting of exercise interventions was poor, with only 4 items (of 19) (21%) of the CERT adequately reported (88-99%), with other items not fulfilled on at least 60% of the RCTs. There were no RCTs that had fulfilled all the criteria for the CERT.

CONCLUSION

The RCTs included in this study poorly reported exercise adherence, as well as description of the post-operative TKA rehabilitation intervention. Future RCTs should use valid and reliable measures of adherence and a proper tool for reporting of exercise interventions (e.g., CERT, TiDER).

PRE-REGISTRATION

OSF: https://osf.io/9ku8a/.

Early Recovery of Walking Ability in Patients After Total Knee Arthroplasty Using a Hip-Wearable Exoskeleton Robot: A Case-Controlled Clinical Trial

Introduction:

The Honda Walking Assist (HWA) is a hip-wearable exoskeleton robot for gait training that assists in hip flexion and extension movements to guide hip joint movements during gait. This study aimed to evaluate the effects of walking exercises with HWA in patients who underwent total knee arthroplasty (TKA).

Materials and Methods:

This study involved 10 patients (11 knees) in the HWA group and 11 patients (11 knees) in the control group who underwent conventional physical therapy. The patients assigned to the HWA group underwent a total of 17-20 gait training sessions, each lasting approximately 20 min from week 1 to 5 following TKA. Self-selected walking speed (SWS), maximum walking speed (MWS), range of motion (ROM), knee extension and flexion torque, and Western Ontario and McMaster Universities Osteoarthritis Index subscales of pain (WOMAC-p) and physical function (WOMAC-f) scores were measured preoperatively, at 2, 4, and 8 weeks following TKA.

Results:

Interventions were successfully completed in all patients, with no severe adverse events. A significant difference was noted in the time × group interaction effect between preoperative and week 2 SWS and MWS. Regarding knee function, there was a significant difference in the time × group interaction between preoperative and week 2 active ROM extension; however, no significant difference in knee torque, WOMAC-p, and WOMAC-f scores were observed. In the between-group post hoc analysis, WOMAC-f in the HWA group was higher than that in the control group at week 8.

Discussion:

Although the control group showed a temporary reduction in SWS and MWS 2 weeks after TKA, the HWA group did not. These results suggest that HWA intervention promotes early improvement in walking ability after TKA.

Conclusions:

The gait training using HWA was safe and feasible and could be effective for the early improvement of walking ability in TKA patients.

Evaluation of a lower-extremity robotic exoskeleton for people with knee osteoarthritis

A multi-site study was conducted to evaluate the efficacy of the Keeogo™ exoskeleton as a mobility assist device for use in the clinic and at home in people with knee osteoarthritis (KOA). Twenty-four participants were randomized in a two-stage cross-over design that evaluated the immediate effects of using the exoskeleton in the clinic and the cumulative effects of training and home use. Immediate effects were quantified by comparing 1) physical performance with|without (W|WO) the device during a battery of mobility tests, and 2) physical activity levels at home (actigraphy) for one month, two weeks W|WO the device. Cumulative effects were quantified as change in physical performance W and WO over time. WOMAC and other self-report scales were measured and usability assessed. There were no immediate effects on physical performance or physical activity at home; however, there were cumulative effects as indicated by improved stair time (p = .001) as well as improved WOMAC pain (p = .004) and function (p = .003). There was a direct relationship between improved physical function and improved WOMAC pain (r = -.677, p < .001) and stiffness (r = .537, p = .007). Weight and battery life were identified as important to usability. A full-scale RCT with more participants, longer study period, and better usage monitoring is warranted.

Wearable rehabilitation exoskeletons of the lower limb: analysis of versatility and adaptability

PURPOSE

To analyse the versatility and adaptability of commercially available exoskeletons for mobility assistance and their adaptation to diverse pathologies through a review of clinical trials in robotic lower limb training.

DATA SOURCES

A computer-aided search in bibliographic databases (PubMed and Web of Science) of clinical trials published up to September 2020 was done.

METHODS

To be selected for detailed review, clinical trials had to meet the following criteria: (1) a protocol was designed and approved, (2) participants were people with pathologies, and (3) the trials were not a single case study. Clinical trial data were collected, extracted, and analysed, considering: objectives, trial participants, number of sessions, pathologies involved, and conclusions.

RESULTS

The search resulted in 312 potentially relevant studies of seven commercial exoskeletons, of which 135 passed the preliminary screening; and 69 studies were finally selected. Of the 69 clinical trials included in the review about 50% involved Spinal Cord Injury participants, while roughly 25% focussed on stroke and two trials corresponded to patients with both disorders. The rest were composed of neurological diseases and trauma disorders.

CONCLUSIONS

The use of a single wearable robot for different medical conditions in various diseases is a challenge. Based on this comparative, the properties of the exoskeletons that improve the working ability with different pathologies and patient conditions have been evaluated. Suggestions were made for developing a new lower-limb exoskeleton based on various modules with a distributed control system to improve versatility in wearable technology for different gait pattern progression.Implications for rehabilitationWearable robotic exoskeletons for gait assistance have been analysed from the perspective of adaptation to different diseases.This paper emphasizes the importance of personalized therapies and adaptive assistive technology.Suggestions were made for a new modular exoskeleton capable of addressing the issue of low versatility characterizing currently wearable assistive technology.

Effects of Robot-Assisted Gait Training in Patients with Burn Injury on Lower Extremity: A Single-Blind, Randomized Controlled Trial

This study investigated the effects of robot-assisted gait training (RAGT) on gait function in burn patients. Briefly, 40 burn patients were randomly divided into an RAGT group or a conventional training (CON) group. SUBAR^® (Cretem, Korea) is a wearable robot with a footplate that simulates normal gait cycles. The RAGT group underwent 30 min of robot-assisted training using SUBAR^® with 30 min of conventional physiotherapy once a day, 5 days a week for 12 weeks. Patients in the CON group received 30 min of overground gait training and range-of-motion (ROM) exercises twice a day for 5 days a week for 12 weeks. The RAGT group and the CON group underwent 60 min of training per day. The intervention frequency and duration did not differ between the RAGT group and the CON group. The main outcomes were functional ambulatory category (FAC); 6-min walking test (6MWT); visual analogue scale (VAS) during gait movement; ROM; and isometric forces of bilateral hip, knee, and ankle muscles before and after 12 weeks of training. The results of the VAS, FAC, and 6MWT (8.06 ± 0.66, 1.76 ± 0.56, and 204.41 ± 85.60) before training in the RAGT group improved significantly (4.41 ± 1.18, 4.18 ± 0.39, and 298.53 ± 47.75) after training (p < 0.001, p < 0.001, and p < 0.001). The results of the VAS, FAC, and 6MWT (8.00 ± 1.21, 1.75 ± 0.58, and 220.94 ± 116.88) before training in the CON group improved significantly (5.00 ± 1.03, 3.81 ± 1.05, and 272.19 ± 110.14) after training (p < 0.001, p < 0.001, and p = 0.05). There were differences in the improvement of results of the VAS, FAC, and 6MWT between groups after training, but they were not statistically significant (p = 0.23, p = 0.14, and p = 0.05). The isometric strengths of the right hip extensor (p = 0.02), bilateral knee flexor (p = 0.04 in the right, and p = 0.001 in the left), bilateral knee extensor (p = 0.003 in the right, and p = 0.002 in the left), bilateral ankle dorsiflexor (p = 0.04 in the right, and p = 0.02 in the left), and bilateral ankle plantarflexor (p = 0.001 in the right, and p = 0.008 in the left) after training were significantly improved compared with those before training in the RAGT group. The ROMs of the right knee extension (p = 0.03) and bilateral ankle plantarflexion (p = 0.008 in the right, and p = 0.03 in the left) were significantly improved compared with measurements before training in the RAGT. There were no significant differences of the isometric strengths and ROMs of the bilateral hip, knee, and ankle muscles after training in the CON group. There were significant improvements in the isometric strengths of the left knee flexor (p = 0.01), left ankle dorsiflexor (p = 0.01), and left ankle plantarflexor (p = 0.003) between the two groups. The results suggested that RAGT is effective to facilitate early recovery of muscles strength after a burn injury. This is the first study to evaluate the effectiveness of RAGT in patients with burns compared with those receiving conventional training. The absence of complications in burn patients provides an opportunity to enlarge the application area of RAGT.

Hybrid assistive limb (HAL) treatment for patients with severe thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL) in the postoperative acute/subacute phase: A clinical trial

Context/Objective: The hybrid assistive limb (HAL) is a wearable exoskeleton robot that assists walking and lower limb movements via real-time actuator control. Our aim was to clarify the safety and feasibility of using the HAL robotic suit for rehabilitation in patients with severe thoracic myelopathy due to ossification of the posterior longitudinal ligament (T-OPLL). Design: Uncontrolled case series; pre- and post-intervention measurement. Setting: In-patient rehabilitation unit. Intervention: HAL training was provided in 60-minuts session, 2-3 sessions per week, for a total of 10 sessions. HAL training was initiated on average 27.5 days post-surgery. Patients: Eight patients (four males and four females; mean age, 60.9 ± 10.2 years) with severe myelopathy, who had undergone posterior decompression with instrumented fusion, were enrolled. Outcome Measures: Gait speed, step length and cadence were measured along a 10-m walkway every session. The American Spinal Injury Association (ASIA) motor score (lower extremities) and Walking Index for Spinal Cord Injury (WISCI) II were also evaluated at baseline and after 10 sessions. The Japanese Orthopaedic Association (JOA) score was calculated over time after surgery. Results: All participants completed the 10 training sessions, with no serious adverse effect noted. Gait speed, step length and cadence improved over time. Both the WISCI-II and ASIA motor (lower extremities) scores improved from baseline after 10 sessions. The JOA score improved over time post-surgery. Conclusion: HAL training can be feasibly initiated in the early postoperative period, without severe adverse events in patients, with T-OPLL-related severe gait disturbance.

Training with Hybrid Assistive Limb for walking function after total knee arthroplasty

BACKGROUND

The Hybrid Assistive Limb (HAL, CYBERDYNE) is a wearable robot that provides assistance to patients while walking, standing, and performing leg movements based on the intended movement of the wearer. We aimed to assess the effect of HAL training on the walking ability, range of motion (ROM), and muscle strength of patients after total knee arthroplasty (TKA) for osteoarthritis and rheumatoid arthritis, and to compare the functional status after HAL training to the conventional training methods after surgery.

METHODS

Nine patients (10 knees) underwent HAL training (mean age 74.1 ± 5.7 years; height 150.4 ± 6.5 cm; weight 61.2 ± 8.9 kg), whereas 10 patients (11 knees) underwent conventional rehabilitation (mean age 78.4 ± 8.0 years; height 150.5 ± 10.0 cm; weight 59.1 ± 9.8 kg). Patients underwent HAL training during 10 to 12 (average 14.4 min a session) sessions over a 4-week period, 1 week after TKA. There was no significant difference in the total physical therapy time including HAL training between the HAL and control groups. Gait speed, step length, ROM, and muscle strength were evaluated.

RESULTS

The nine patients completed the HAL training sessions without adverse events. The walking speed and step length in the self-selected walking speed condition, and the walking speed in the maximum walking speed condition were greater in the HAL group than in the control group at 4 and 8 weeks (P < 0.05). The step length in the maximum walking speed condition was greater in the HAL group than in the control group at 2, 4, and 8 weeks (P < 0.05). The extension lag and knee pain were lower in the HAL group than in the control group at 2 weeks (P < 0.05). The muscle strength of knee extension in the HAL group was greater than that in the control group at 8 weeks (P < 0.05).

CONCLUSION

HAL training after TKA can improve the walking ability, ROM, and muscle strength compared to conventional physical therapy for up to 8 weeks after TKA. Since the recovery of walking ability was earlier in the HAL group than in the control group and adverse events were not observed in this pilot study, HAL training after TKA can be considered a safe and effective rehabilitation intervention.

TRIAL REGISTRATION

UMIN, UMIN000017623 . Registered 19 May 2015.