Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

Partial weight-bearing following ankle fracture: what's the actual load in early recovery?

PURPOSE

This study investigates the learning efficacy for partial weight load before discharge as well as the impact of biofeedback during the learning process.

METHODS

We monitored weight-bearing in 57 patients who had surgery for ankle fractures. Continuous measurements without and with biofeedback were performed in the early postoperative stage in order to, first, assess how well these patients could apply what they have learned before being discharged, and second, to examine the influence of biofeedback.

RESULTS

Using conventional teaching methods, only about one-third of patients (36.8% on the ground and 29.2% on the stairs) were able to maintain a satisfactory load. One-fourth of the patients did not place any weight on their leg, which was shown to be due to excessive pain at the time of the measurement (p < 0.05). A further one-fourth loaded inadequately low, while the remainder loaded excessively. Patients benefited significantly from the activation of audio-visual biofeedback in real time. As a result, loads in a target zone between 15 and 30 kg could be significantly increased (p < 0.05).

CONCLUSION

We conclude that the majority of ankle fracture patients were unable to learn partial weight bearing in the early postoperative stage using traditional techniques. Additionally, each patient's ability to carry out a given loading varied. Using an audio-visual real-time biofeedback modality led to significantly improved performance. These findings support the proposed utility of audiovisual feedback in early rehabilitation. With the use of outpatient real-time biofeedback systems, therapists will be able to respond specifically to the needs of each individual patient.

TRIAL REGISTRATION

Trial registration: DRKS00031136, Registered 01.02.2023 - Retrospectively registered, https://www.drks.de/DRKS00031136.

A probabilistic approach for assessing the mechanical performance of intertrochanteric fracture stabilized with proximal femoral nail antirotation

Maintaining post-operative mechanical stability is crucial for successfully healing intertrochanteric fractures treated with the Proximal Femoral Nail Antirotation (PFNA) system. This stability is primarily dependent on the bone mineral density (BMD) and strain on the fracture. Current PFNA failure analyses often overlook the uncertainties related to BMD and body weight (BW). Therefore, this study aimed to develop a probabilistic model using finite element modeling and engineering reliability analysis to assess the post-operative performance of PFNA under various physiological loading conditions. The model predictions were validated through a series of experimental test. The results revealed a negative nonlinear relationship between the BMD and compressive strain. Conversely, the BW was positively and linearly correlated with the compressive strain. Importantly, the compressive strain was more sensitive to BW than to BMD when the BMD exceeded 0.6 g/cm3. Potential trabecular bone compression failure is also indicated if BMD is equal to or below 0.15 g/cm3 and BW increases to approximately 2.5 times the normal or higher. This study emphasizes that variations in the BMD significantly affect the probability of failure of a PFNA system. Thus, careful planning of post-operative physical therapy is essential. For patients aged > 50 years restrictions on high-intensity activities are advised, while limiting strenuous movements is recommended for those aged > 65 years.

Effectiveness of permissive weight bearing in surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities: a prospective comparative multicenter cohort study

PURPOSE

The aim of the present study was to investigate the effectiveness of a novel approach involving permissive weight bearing (PWB) in surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities.

METHODS

Prospective comparative multicenter cohort study in one level 1 trauma center and five level 2 trauma centers. Surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities were included. Permissive weight bearing (PWB) in comparison to restricted weight bearing (RWB) was assessed over a 26-week post-surgery follow-up period. Patients' self-perceived outcome levels regarding activities of daily living (ADL), quality of life (QoL), pain and weight bearing compliance were used.

RESULTS

This study included 106 trauma patients (N = 53 in both the PWB and RWB groups). Significantly better ADL and QoL were found in the PWB group compared to the RWB group at 2-, 6-, 12- and 26-weeks post-surgery. There were no significant differences in postoperative complication rates between the PWB and RWB groups.

CONCLUSION

PWB is effective and is associated with a significantly reduced time to full weight bearing, and a significantly better outcome regarding ADL and QoL compared to patients who followed RWB regimen. Moreover, no significant differences in complication rates were found between the PWB and RWB groups.

LEVEL OF EVIDENCE

Level II.

REGISTRATION

This study is registered in the Dutch Trial Register (NTR6077). Date of registration: 01-09-2016.

Improved weight bearing during gait at 6 weeks post-surgery with an angle stable locking system after distal tibial fracture

BACKGROUND

Functional recovery after intramedullary nailing of distal tibial fractures can be monitored using ipsilateral vertical ground reaction forces (vGRF), giving insight into recovery of patients' gait symmetry. Previous work compared patient cohorts to healthy controls, but it remains unclear if these metrics can identify treatment-based differences in return to function post-surgery.

RESEARCH QUESTION

Is treatment of a distal tibial fracture with intramedullary nailing with an angle stable locking system (ASLS) associated with higher ipsilateral vGRF and improved symmetry compared to conventional intramedullary nailing at an early time point?

METHODS

Thirty-nine patients treated with ASLS intramedullary nailing were retrospectively compared to thirty-nine patients with conventional locking. vGRFs were collected at 1, 6, 12, 26, and 52 weeks post-surgery during standing and gait. Discrete metrics of ipsilateral vGRF (maximal force, impulse) and asymmetry were compared between treatments at each time point. Time-scale comparisons of ipsilateral vGRF and lower limb asymmetry were additionally performed for gait trials. Mann-Whitney Test or a two-way analysis of variance tested discrete comparisons; statistical non-parametric mapping tested time-scale data between treatment groups.

RESULTS

During gait, ASLS-treated patients applied more load on the operated limb (17-38% stance, p = 0.015) and consequently loaded limbs more symmetrically (8-37% stance, p = 0.008) during the loading response at 6 weeks post-surgery compared to conventional IM treatment. Discrete measures of symmetry at the same time point identified treatment-based differences in maximal force (p = 0.039) and impulse (p = 0.012), with ASLS-treated patients exhibiting more symmetry. No differences were identified in gait trials at later time points nor from all standing trials.

SIGNIFICANCE

During the initial loading response of gait, increased ipsilateral vGRF and improved weightbearing symmetry were identified in ASLS patients at 6 weeks post-surgery compared to conventional IM nailing. Early and objective metrics of dynamic movement are suggested to identify treatment-based differences in functional recovery.

Digital monitoring of weight-bearing improves success rates and reduces complications in lower extremity surgeries

The aim of this study is to develop a digital monitoring system to track weight and evaluate its impact on postoperative outcomes after lower extremity surgeries (LES). This parallel randomized controlled trial enrolled 266 patients who underwent LES (fracture or joint replacement) at our medical center between March 11, 2022, and January 10, 2023. Patients were randomly assigned to the intervention and control groups in a 1:1 ratio. The intervention group (n=116) used a cane and shoes equipped with a weight-bearing system after lower limb surgery, while the control group (n=116) used a simple cane and shoes without a weight-bearing system. The primary outcomes included callus formation, duration of union, and success rate of union in the two groups. The intervention group had a significantly higher rate of complete surgical success than the control group (93.9% vs. 79.3%, p=0.001). The intervention group also had a significantly lower risk of non-union than the control group (OR: 2.33, 95% CI: 1.14, 3.48, p=0.001). The mean duration of surgery until the time of union and the meantime of callus formation was significantly lower in the intervention group (p=0.01). The use of a digital monitoring system for weighing in LES significantly increased the success rate and reduced post-operative complications. Therefore, incorporating this system can enhance the rehabilitation process and prevent revision surgeries in patients with LES.

A Wearable Biofeedback Device for Monitoring Tibial Load During Partial Weight-Bearing Walking

Patients with tibial fractures are usually advised to follow a partial weight-bearing gait rehabilitation program after surgery to promote bone healing and lower limb functional recovery. Currently, the biofeedback devices used for gait rehabilitation training in fracture patients use ground reaction force (GRF) as the indicator of tibial load. However, an increasing body of research has shown that monitoring GRF alone cannot objectively reflect the load on the lower limb bones during human movement. In this study, a novel biofeedback system was developed utilizing inertial measurement units and custom instrumented insoles. Based on the data collected from experiments, a hybrid approach combining a physics-based model and neural network architectures was used to predict tibial force. Compared to the traditional physics-based algorithm, the physical guided neural networks method showed better predictive performance. The study also found that regardless of the type of weight-bearing walking, the peak tibial force was significantly higher than the peak tibial GRF, and the time at which the peak tibial compression force occurs may not be consistent with the time at which the peak vertical GRF occurs. This further supports the idea that during gait rehabilitation training for patients with tibial fractures, monitoring and providing feedback on the actual tibial force rather than just the GRF is necessary. The developed device is a non-invasive and reliable portable device that can provide audio feedback, providing a viable solution for gait rehabilitation training outside laboratory and helping to optimize patients' rehabilitation treatment strategies.

Validation of Estimators for Weight-Bearing and Shoulder Joint Loads Using Instrumented Crutches

This research paper aimed to validate two methods for measuring loads during walking with instrumented crutches: one method to estimate partial weight-bearing on the lower limbs and another to estimate shoulder joint reactions. Currently, gait laboratories, instrumented with high-end measurement systems, are used to extract kinematic and kinetic data, but such facilities are expensive and not accessible to all patients. The proposed method uses instrumented crutches to measure ground reaction forces and does not require any motion capture devices or force platforms. The load on the lower limbs is estimated by subtracting the forces measured by the crutches from the subject's total weight. Since the model does not consider inertia contribution in dynamic conditions, the estimation improves with low walking cadence when walking with the two-point contralateral and the three-point partial weight-bearing patterns considered for the validation tests. The shoulder joint reactions are estimated using linear regression, providing accurate values for the forces but less accurate torque estimates. The crutches data are acquired and processed in real-time, allowing for immediate feedback, and the system can be used outdoors in real-world walking conditions. The validation of this method could lead to better monitoring of partial weight-bearing and shoulder joint reactions, which could improve patient outcomes and reduce complications.

Training to Improve the Landing of an Uninjured Leg in Crutch Walk Using AR Technology to Present an Obstacle

A patient who unexpectedly sustains a lower leg injury often uses crutches for walking, to both assist the patient and prevent further injury until a full recovery is made. In this study, a novel crutch walk training system was developed; a head-mounted display (HMD) was introduced to present a virtual obstacle for trainees using crutches. Through repetitions of the training, it was expected that the trainees would improve their overall body stability. Healthy subjects participated in experimental training exercises using the developed training system. As a result, the participants acquired the skill of walking well with crutches without losing their body balance significantly, even in the event of facing a virtual obstacle, during the five training sessions.

Feedback Training Improves Compliance with Sternal Precaution Guidelines during Functional Mobility: Implications for Optimizing Recovery in Older Patients after Median Sternotomy

Patients often need to use their arms to assist with functional activities, but after open heart surgery, pushing with the arms is limited to <10 lb (4.5 kg) to help minimize force across the healing sternum. The main purposes of this study were to determine if older patients (>60 years old) (1) accurately estimated upper extremity (UE) weight bearing force of 10 lb or less and (2) if feedback training improved their ability to limit UE force and pectoralis major muscle contraction during functional activities. An instrumented walker was used to measure UE weight bearing force, and electromyography was used to measure pectoralis major muscle activity simultaneously during 4 functional mobility tasks. After baseline testing, healthy older subjects (n = 30) completed a brief session of visual and auditory concurrent feedback training. Results showed that the self-selected UE force was >10 lb for all tasks (20.0-39.7 lb [9.1-18.0 kg]), but after feedback training, it was significantly reduced (10.6-21.3 lb [4.8-9.7 kg]). During most trials (92%), study participants used >12 lb (5.5 kg) of arm weight bearing force. Pectoralis major muscle peak electromyography activity was <23% of maximal voluntary isometric contraction and was reduced (9.8-14.9%) after feedback training. Older patients may not be able to accurately estimate UE arm force used during weight bearing activities, and visual and auditory feedback improves accuracy and also modulation of pectoralis major muscle activation. Results suggest that an instrumented walker and feedback training could be clinically useful for older patients recovering from open heart surgery.

Mobilising the patient: With emphasis on innovative technologies

Treatment of trauma patients and fractures has changed dramatically throughout the years. From conservative methods to nowadays various kinds of screws, pins, plates and nails for optimal fixation of fractures. This lead to changes in post-operative management as well, from bedrest to (partial) weight bearing. Some patients however have very limited to no ability to mobilise, such as critical ill patients on the Intensive Care Unit, amputees or spinal cord injured patients. Due to innovations such as hydrotherapy, osseointegrated prosthesis and exoskeletons, even these people can mobilise. Thanks to innovations like these an increasing number of trauma patients are able to fully reintegrate into community life and get back to an active and independent life style.

How New Technology Is Improving Physical Therapy

PURPOSE OF REVIEW

As rehabilitation patient volume across the age spectrum increases and reimbursement rates decrease, clinicians are forced to produce favorable outcomes with limited resources and time. The purpose of this review is to highlight new technologies being utilized to improve standardization and outcomes for patients rehabilitating orthopedic injuries ranging from sports medicine to trauma to joint arthroplasty.

RECENT FINDINGS

A proliferation of new technologies in rehabilitation has recently occurred with the hope of improved outcomes, better patient compliance and safety, and return to athletic performance. These include technologies applied directly to the patient such as exoskeletons and instrumented insoles to extrinsic applications such as biofeedback and personalized reference charts. Well-structured randomized trials are ongoing centered around the efficacy and safety of these new technologies to help guide clinical necessity and appropriate application. We present a range of new technologies that may assist a diverse population of orthopedic conditions. Many of these interventions are already supported by level 1 evidence and appear safe and feasible for most clinical settings.

COMplex Fracture Orthopedic Rehabilitation (COMFORT) - Real-time visual biofeedback on weight bearing versus standard training methods in the treatment of proximal femur fractures in the elderly: study protocol for a multicenter randomized controlled trial

Background

Proximal femur fractures are a common injury after low energy trauma in the elderly. Most rehabilitation programs are based on restoring mobility and early resumption of weight-bearing. However, therapy compliance is low in patients following lower extremity fractures. Moreover, little is known about the relevance of gait parameters and how to steer the rehabilitation after proximal femur fractures in the elderly. Therefore, the aim of this prospective, randomized controlled trial is to gain insight in gait parameters and evaluate if real-time visual biofeedback can improve therapy compliance after proximal femur fractures in the elderly.

Methods

This is a two-arm, parallel-design, prospective, randomized controlled trial. Inclusion criteria are age ≥ 60 years, a proximal femur fracture following low energy trauma, and unrestricted-weight bearing. Exclusion criteria are cognitive impairment and limited mobility before trauma. Participants are randomized into either the control group, which receives care as usual, or the intervention group, which receives real-time visual biofeedback about weight-bearing during gait in addition to care as usual. Spatiotemporal gait parameters will be measured in 94 participants per group during a 30-m walk with an ambulatory biofeedback system (SensiStep). The progress of rehabilitation will be evaluated by the primary outcome parameters maximum peak load and step duration in relation to the discharge date. Secondary outcome parameters include other spatiotemporal gait parameters in relation to discharge date. Furthermore, the gait parameters will be related to three validated clinical tests: Elderly Mobility Scale; Functional Ambulation Categories; and Visual Analogue Scale. The primary hypothesis is that participants in the intervention group will show improved and faster rehabilitation compared to the control group.

Discussion

The first aim of this multicenter trial is to investigate the normal gait patterns after proximal femur fractures in the elderly. The use of biofeedback systems during rehabilitation after proximal femur fractures in the elderly is promising; therefore, the second aim is to investigate the effect of real-time visual biofeedback on gait after proximal femur fractures in the elderly. This could lead to improved outcome. In addition, analysis of the population may indicate characteristics of subgroups that benefit from feedback, making a differentiated approach in rehabilitation strategy possible.

Trial registration

TrialRegister.nl, NTR6794. Registered on 31 October 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2612-9) contains supplementary material, which is available to authorized users.

Real-time visual biofeedback to improve therapy compliance after total hip arthroplasty: A pilot randomized controlled trial

BACKGROUND

Previous studies have shown limited therapy compliance in weight-bearing in patients following total hip arthroplasty.

RESEARCH QUESTION

The purpose of this pilot RCT is to determine the immediate and late effect of real-time, visual biofeedback on weight-bearing during rehabilitation after THA in elderly.

METHODS

24 participants who underwent THA were randomized to either the control or the intervention group. The intervention group received real-time, visual biofeedback on weight-bearing during training with the physical therapist during hospitalization and at twelve weeks follow up.

RESULTS

Without biofeedback, therapy compliance was limited. Significant improvement in peak load was found in the intervention group in the early postoperative phase. In contrast to the control group, the peak load at twelve weeks was significantly higher in the intervention group compared to the pre-operative peak load, indicating a lasting effect of early biofeedback. Other gait parameters were not significantly different in the early postoperative phase. In the intervention group a longer walking distance was observed and the use of walking aids was reduced at twelve weeks.

SIGNIFICANCE

Biofeedback systems could be promising to improve outcomes and reduce costs in future rehabilitation programs after THA.