A novel tool for continuous fracture aftercare - Clinical feasibility and first results of a new telemetric gait analysis insole

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.

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.

Long-term continuous instrumented insole-based gait analyses in daily life have advantages over longitudinal gait analyses in the lab to monitor healing of tibial fractures

Introduction: Monitoring changes in gait during rehabilitation allows early detection of complications. Laboratory-based gait analyses proved valuable for longitudinal monitoring of lower leg fracture healing. However, continuous gait data recorded in the daily life may be superior due to a higher temporal resolution and differences in behavior. In this study, ground reaction force-based gait data of instrumented insoles from longitudinal intermittent laboratory assessments were compared to monitoring in daily life. Methods: Straight walking data of patients were collected during clinical visits and in between those visits the instrumented insoles recorded all stepping activities of the patients during daily life. Results: Out of 16 patients, due to technical and compliance issues, only six delivered sufficient datasets of about 12 weeks. Stance duration was longer (p = 0.004) and gait was more asymmetric during daily life (asymmetry of maximal force p < 0.001, loading slope p = 0.001, unloading slope p < 0.001, stance duration p < 0.001). Discussion: The differences between the laboratory assessments and the daily-life monitoring could be caused by a different and more diverse behavior during daily life. The daily life gait parameters significantly improved over time with union. One of the patients developed an infected non-union and showed worsening of force-related gait parameters, which was earlier detectable in the continuous daily life gait data compared to the lab data. Therefore, continuous gait monitoring in the daily life has potential to detect healing problems early on. Continuous monitoring with instrumented insoles has advantages once technical and compliance problems are solved.

Wearable activity data can predict functional recovery after musculoskeletal injury: Feasibility of a machine learning approach

Delayed functional recovery after injury is associated with significant personal and socioeconomic burden. Identification of patients at risk for a prolonged recovery after a musculoskeletal injury is thus of high relevance. The aim of the current study was to show the feasibility of using a machine learning assisted model to predict functional recovery based on the pre- and immediate post injury patient activity as measured with wearable systems in trauma patients. Patients with a pre-existing wearable (smartphone and/or body-worn sensor), data availability of at least 7 days prior to their injury, and any musculoskeletal injury of the upper or lower extremity were included in this study. Patient age, sex, injured extremity, time off work and step count as activity data were recorded continuously both pre- and post-injury. Descriptive statistics were performed and a logistic regression machine learning model was used to predict the patient's functional recovery status after 6 weeks based on their pre- and post-injury activity characteristics. Overall 38 patients (7 upper extremity, 24 lower extremity, 5 pelvis, 2 combined) were included in this proof-of-concept study. The average follow-up with available wearable data was 85.4 days. Based on the activity data, a predictive model was constructed to determine the likelihood of having a recovery of at least 50 % of the pre-injury activity state by post injury week 6. Based on the individual activity by week 3 a predictive accuracy of over 80 % was achieved on an independent test set (F1=0,82; AUC=0,86; ACC=8,83). The employed model is feasible to assess the principal risk for a slower recovery based on readily available personal wearable activity data. The model has the potential to identify patients requiring additional aftercare attention early during the treatment course, thus optimizing return to the pre-injury status through focused interventions. Additional patient data is needed to adapt the model to more specifically focus on different fracture entities and patient groups.

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.

Temporary Partial Weight-Bearing Restriction in Elderly Patients Treated With a Plate Fixation After a Distal Femur Fracture had a Negative Long-Term Impact on Gait Recovery

Background

Restricted weight-bearing is still used after lower extremity fracture surgery in elderly patients. The long-term effect on gait recovery in elderly patients with distal femur fractures (DFF) and their ability to comply with the restrictive weight-bearing regime is unknown. This study aimed to investigate the effect of restricted postoperative weight-bearing on gait recovery (actual weight-bearing and cadence) during a 1-year follow-up.

Methods

This study evaluated secondary outcomes from a randomized controlled trial (32 patients ≥65 years, with a traumatic DFF). Internal fixation was achieved using an anatomical lateral plate. Patients were allocated to either immediate full weight-bearing (FWB) or partial weight-bearing (PWB) (30% of body weight) for 8 weeks. Pressure-sensitive sensors (F-scan™ system, Tekscan, Massachusetts, USA) were used to measure weight-bearing and cadence postoperatively and at 8-, 16-, and 52-week follow-ups. Twenty-six patients with at least 1 measurement were included.

Results

There was a statistically significant difference in actual weight-bearing between the PWB and FWB groups postoperatively of 32.3% (95% confidence interval CI, -50.0; -13.0, P < .001) and at the 8-week follow-up of 36.8% (95% CI -61.0; -18.0, P = .01), but not at later follow-ups. The PWB group presented a consistently lower cadence compared to the FWB group, which was statistically significant at the 16-week follow-up with 9.0 steps/min (95% CI -16.2; -1.1, P = .047) and 52-week follow-up with 9.3 steps/min (95% CI -18.0; -3.9, P = .009).

Conclusions

Restricting postoperative weight-bearing in elderly patients with a DFF had a significant effect on postoperative weight-bearing. The effect lingered with a delayed return to FWB and persistent significantly lower cadence in the PWB group. These findings suggest that even temporary weight-bearing restrictions most likely have negative long-term effects on gait function at 1 year and, therefore, cannot be recommended.

The Influence of Age and Physical Activity on Locomotor Adaptation

BACKGROUND

Aging increases individual susceptibility to falls and injuries, suggesting poorer adaptation of balance responses to perturbation during locomotion, which can be measured with the locomotor adaptation task (LAT). However, it is unclear how aging and lifestyle factors affect these responses during walking. Hence, the present study investigates the relationship between balance and lifestyle factors during the LAT in healthy individuals across the adult lifespan using a correlational design.

METHODS

Thirty participants aged 20-78 years performed an LAT on a split-belt treadmill (SBT). We evaluated the magnitude and rate of adaptation and deadaptation during the LAT. Participants reported their lifelong physical and cognitive activity.

RESULTS

Age positively correlated with gait-line length asymmetry at the late post-adaptation phase (p = 0.007). These age-related effects were mediated by recent physical activity levels (p = 0.040).

CONCLUSION

Our results confirm that locomotor adaptive responses are preserved in aging, but the ability to deadapt newly learnt balance responses is compromised with age. Physical activity mediates these age-related effects. Therefore, gait symmetry post-adaptation could effectively measure the risk of falling, and maintaining physical activity could protect against declines in balance.

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.

Insole Systems for Disease Diagnosis and Rehabilitation: A Review

Some chronic diseases, including Parkinson's disease (PD), diabetic foot, flat foot, stroke, elderly falling, and knee osteoarthritis (KOA), are related to orthopedic organs, nerves, and muscles. The interaction of these three parts will generate a comprehensive result: gait. Furthermore, the lesions in these regions can produce abnormal gait features. Therefore, monitoring the gait features can assist medical professionals in the diagnosis and analysis of these diseases. Nowadays, various insole systems based on different sensing techniques have been developed to monitor gait and aid in medical research. Hence, a detailed review of insole systems and their applications in disease management can greatly benefit researchers working in the field of medical engineering. This essay is composed of the following sections: the essay firstly provides an overview of the sensing mechanisms and parameters of typical insole systems based on different sensing techniques. Then this essay respectively discusses the three stages of gait parameters pre-processing, respectively: pressure reconstruction, feature extraction, and data normalization. Then, the relationship between gait features and pathogenic mechanisms is discussed, along with the introduction of insole systems that aid in medical research; Finally, the current challenges and future trends in the development of insole systems are discussed.

Gait Analysis to Monitor Fracture Healing of the Lower Leg

Fracture healing is typically monitored by infrequent radiographs. Radiographs come at the cost of radiation exposure and reflect fracture healing with a time lag due to delayed fracture mineralization following increases in stiffness. Since union problems frequently occur after fractures, better and timelier methods to monitor the healing process are required. In this review, we provide an overview of the changes in gait parameters following lower leg fractures to investigate whether gait analysis can be used to monitor fracture healing. Studies assessing gait after lower leg fractures that were treated either surgically or conservatively were included. Spatiotemporal gait parameters, kinematics, kinetics, and pedography showed improvements in the gait pattern throughout the healing process of lower leg fractures. Especially gait speed and asymmetry measures have a high potential to monitor fracture healing. Pedographic measurements showed differences in gait between patients with and without union. No literature was available for other gait measures, but it is expected that further parameters reflect progress in bone healing. In conclusion, gait analysis seems to be a valuable tool for monitoring the healing process and predicting the occurrence of non-union of lower leg fractures.

Clinical Assessments of Fracture Healing and Basic Science Correlates: Is There Room for Convergence?

PURPOSE OF REVIEW

The purpose of this review is to summarize the clinical and basic science methods used to assess fracture healing and propose a framework to improve the translational possibilities.

RECENT FINDINGS

Mainstays of fracture healing assessment include clinical examination, various imaging modalities, and assessment of function. Pre-clinical studies have yielded insight into biomechanical progression as well as the genetic, molecular, and cellular processes of fracture healing. Efforts are emerging to identify early markers to predict impaired healing and possibly early intervention to alter these processes. Despite of the differences in clinical and preclinical research, opportunities exist to unify and improve the translational efforts between these arenas to develop and optimize our ability to assess and predict fracture healing, thereby improving the clinical care of these patients.

Characteristics and Effectiveness of Postoperative Rehabilitation Strategies in Ankle Fractures: A Systematic Review

OBJECTIVES

To explore the characteristics and to report on the effectiveness of postoperative rehabilitation strategies for people with an ankle fracture.

DATA SOURCES

PubMed, Cochrane Library, EMBASE, Web of Science, and CINAHL were searched to identify studies published from January 2010 to November 2021.

STUDY SELECTION

Studies that described or evaluated postoperative rehabilitation strategies for surgically repaired ankle fractures were included.

DATA EXTRACTION

Data on postoperative rehabilitation were extracted in accordance with the Template for Intervention Description and Replication guide. Quality was assessed using the National Heart, Lung, and Blood Institute's Study Quality Assessment Tools.

DATA SYNTHESIS

Meta-analysis was planned to look at the effectiveness of postoperative rehabilitation strategies. Forty studies described postoperative rehabilitation strategies without evaluating effectiveness, whereas 15 studies focused on evaluating effectiveness. Because of the large variety in postoperative strategies and outcomes, narrative synthesis was deemed most suitable to answer our aims. Characteristics of postoperative rehabilitation strategies varied widely and were poorly described in a way that could not be replicated. Most of the studies (48%) used a late weight-bearing approach, although definitions and details around weight-bearing were unclear.

CONCLUSIONS

Late weight-bearing has been the most common postoperative approach reported in the past 10 years. The variety of definitions around weight-bearing and the lack of details of rehabilitation regimens limit replication and affect current clinical practice. The authors propose to adopt consistent definitions and terminology around postoperative practices such as weight-bearing to improve evidence for effectiveness and ultimately patient outcomes.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Effectiveness of Rehabilitation Program After Hybrid Osteosynthesis in Ankle Joint Unstable Injuries

Aim: To develop a rehabilitation protocol for patients with the unstable ankle joint injuries by doing comparative analysis between HSEF functional results and the traditional method. Materials and Methods: The study was performed on 61 patients with the unstable ankle trans- or supra-syndesmotic fractures. Patients were divided into two equal groups where I = main and II = control due to the age, distribution and disorders. 10 patients from the group I were operated using HSEF, the other 51 were selected for the traditional osteosynthesis (plate and positioning screw). For the monitoring of osteosynthesis quality was used The Foot and Ankle Disability Index (FADI) scale. Nonparametric statistical analysis was completed using Statistica 13.0 computer software. Results: After application of HSEF method authors of this paper created original rehabilitation protocol. Limitations in the rehabilitation process (e.g., not weightbearing) on 42}3 day in the control group II caused a significant gap in the results of ankle joint functional recovery. On day56}3, the main group I overreached the control group II by 1.5 (p3<0.001). With each FU 1-3 of the main group I, the total sum of points according to FADI (subscale of sports activity) steadily increased by 5, and with FU 3 on the 56}3 day, reached 16 points. Positive quantitative dynamics in scores were the characteristic of patients from both groups (advantage of the group I was insignificant (by 2 points) (p4<0.001)), although none of them reached the normal (32 points) at the final term (FU 4). Conclusion:Provided results proved the effectiveness of the developed rehabilitation protocol. It enhanced patients recovery up to 1-2 weeks.

Gait Analysis in Orthopaedic Surgery: History, Limitations, and Future Directions

Gait analysis has expanding indications in orthopaedic surgery, both for clinical and research applications. Early work has been particularly helpful for understanding pathologic gait deviations in neuromuscular disorders and biomechanical imbalances that contribute to injury. Notable advances in image acquisition, health-related wearable devices, and computational capabilities for big data sets have led to a rapid expansion of gait analysis tools, enabling novel research in all orthopaedic subspecialties. Given the lower cost and increased accessibility, new gait analysis tools will surely affect the next generation of objective patient outcome data. This article reviews the basic principles of gait analysis, modern tools available to the common surgeon, and future directions in this space.

Immediate Postoperative Improvement in Gait Parameters following Primary Total Knee Arthroplasty Can Be Measured with an Insole Sensor Device

Total knee arthroplasty (TKA) improves the quality of life in those suffering from debilitating arthritis of the knee. However, little is known about the influence of TKA on restoring physical function. Prior studies have used artificial means, such as instrumented treadmills, to assess physical function after TKA. In this study an insole sensor device was used to quantify parameters of gait. The purpose of this study was to evaluate the ability of a wearable insole sensor device to measure immediate postoperative gait parameters at 2 weeks and 6 weeks following primary TKA and to determine if the device was suitable and sensitive enough to identify and measure potentially subtle changes in these measures at these early postoperative time periods. Twenty-nine patients with unilateral TKA, without contralateral knee pain, and aid-free walking before surgery were evaluated. An insole force sensor measured the postoperative parameters while walking a distance of 40 m on level ground at 2 and 6 weeks after TKA. The loading rate of the operated lower extremity was an average of 68.7% of the contralateral side at 2 weeks post-surgery and increased to 82.1% at 6 weeks post-surgery (p < 0.001). The mean gait speed increased from 0.75 to 1.02 m/s, (p < 0.001) and cadence increased from 82.9 to 99.9 steps/min (p < 0.001), while the numeric pain scale at rest decreased from 3.5/10 to 2.2/10, (p < 0.001) and the pain while walking from 3.9/10 to 2.4/10, (p < 0.001) from 2 to 6 weeks post-surgery. A significant improvement in gait parameters is detectable in the first 6 weeks after surgery with the use of a wearable insole device. As the gait speed and cadence increase and the VAS pain level decreases, the loading rate and average peak force begin to normalize. This device may allow for early gait analysis and have potential clinical utility in detecting early differences in patients' functional status following TKA.

Validity and Reliability of the Insole3 Instrumented Shoe Insole for Ground Reaction Force Measurement during Walking and Running

Pressure-detecting insoles such as the Insole3 have potential as a portable alternative for assessing vertical ground reaction force (vGRF) outside of specialized laboratories. This study evaluated whether the Insole3 is a valid and reliable alternative to force plates for measuring vGRF. Eleven healthy participants walked overground at slow and moderately paced speeds and ran at a moderate pace while collecting vGRF simultaneously from a force plate (3000 Hz) and Insole3 (100 Hz). Intraclass correlation coefficients (ICC) demonstrated excellent vGRF agreement between systems during both walking speeds for Peak 1, Peak 2, the valley between peaks, and the vGRF impulse (ICC > 0.941). There was excellent agreement during running for the single vGRF peak (ICC = 0.942) and impulse (ICC = 0.940). The insoles slightly underestimated vGRF peaks (−3.7% to 0.9% bias) and valleys (−2.2% to −1.8% bias), and slightly overestimated impulses (4.2% to 5.6% bias). Reliability between visits for all three activities was excellent (ICC > 0.970). The Insole3 is a valid and reliable alternative to traditional force plates for assessing vGRF during walking and running in healthy adults. The excellent ICC values during slow walking suggests that the Insole3 may be particularly suitable for older adults in clinical and home settings.

Gait Alterations in Adults after Ankle Fracture: A Systematic Review

(1) Background: Ankle fracture results in pain, swelling, stiffness and strength reduction, leading to an altered biomechanical behavior of the joint during the gait cycle. Nevertheless, a common pattern of kinematic alterations has still not been defined. To this end, we analyzed the literature on instrumental gait assessment after ankle fracture, and its correlation with evaluator-based and patient-reported outcome measures. (2) Methods: We conducted a systematic search, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, of articles published from January 2000 to June 2021 in PubMed, Embase and PEDro on instrumental gait assessment after ankle fracture. (3) Results: Several changes in gait occur after ankle fracture, including a reduction in step length, swing time, single support time, stride length, cadence, speed and an earlier foot-off time in the affected side. Additionally, trunk movement symmetry (especially vertical) is significantly reduced after ankle fracture. The instrumental assessments correlate with different clinical outcome measures. (4) Conclusions: Instrumental gait assessment can provide an objective characterization of the gait alterations after ankle fracture. Such assessment is important not only in clinical practice to assess patients’ performance but also in clinical research as a reference point to evaluate existing or new rehabilitative interventions.

Prediction of Physical Frailty in Orthogeriatric Patients Using Sensor Insole-Based Gait Analysis and Machine Learning Algorithms: Cross-sectional Study

Background

Assessment of the physical frailty of older patients is of great importance in many medical disciplines to be able to implement individualized therapies. For physical tests, time is usually used as the only objective measure. To record other objective factors, modern wearables offer great potential for generating valid data and integrating the data into medical decision-making.

Objective

The aim of this study was to compare the predictive value of insole data, which were collected during the Timed-Up-and-Go (TUG) test, to the benchmark standard questionnaire for sarcopenia (SARC-F: strength, assistance with walking, rising from a chair, climbing stairs, and falls) and physical assessment (TUG test) for evaluating physical frailty, defined by the Short Physical Performance Battery (SPPB), using machine learning algorithms.

Methods

This cross-sectional study included patients aged >60 years with independent ambulation and no mental or neurological impairment. A comprehensive set of parameters associated with physical frailty were assessed, including body composition, questionnaires (European Quality of Life 5-dimension [EQ 5D 5L], SARC-F), and physical performance tests (SPPB, TUG), along with digital sensor insole gait parameters collected during the TUG test. Physical frailty was defined as an SPPB score≤8. Advanced statistics, including random forest (RF) feature selection and machine learning algorithms (K-nearest neighbor [KNN] and RF) were used to compare the diagnostic value of these parameters to identify patients with physical frailty.

Results

Classified by the SPPB, 23 of the 57 eligible patients were defined as having physical frailty. Several gait parameters were significantly different between the two groups (with and without physical frailty). The area under the receiver operating characteristic curve (AUROC) of the TUG test was superior to that of the SARC-F (0.862 vs 0.639). The recursive feature elimination algorithm identified 9 parameters, 8 of which were digital insole gait parameters. Both the KNN and RF algorithms trained with these parameters resulted in excellent results (AUROC of 0.801 and 0.919, respectively).

Conclusions

A gait analysis based on machine learning algorithms using sensor soles is superior to the SARC-F and the TUG test to identify physical frailty in orthogeriatric patients.

A Single Session of Anodal Cerebellar Transcranial Direct Current Stimulation Does Not Induce Facilitation of Locomotor Consolidation in Patients With Multiple Sclerosis

Background: Multiple sclerosis (MS) may cause variable functional impairment. The discrepancy between functional impairment and brain imaging findings in patients with MS (PwMS) might be attributed to differential adaptive and consolidation capacities. Modulating those abilities could contribute to a favorable clinical course of the disease.

Objectives: We examined the effect of cerebellar transcranial direct current stimulation (c-tDCS) on locomotor adaptation and consolidation in PwMS using a split-belt treadmill (SBT) paradigm.

Methods: 40 PwMS and 30 matched healthy controls performed a locomotor adaptation task on a SBT. First, we assessed locomotor adaptation in PwMS. In a second investigation, this training was followed by cerebellar anodal tDCS applied immediately after the task ipsilateral to the fast leg (T0). The SBT paradigm was repeated 24 h (T1) and 78 h (T2) post-stimulation to evaluate consolidation.

Results: The gait dynamics and adaptation on the SBT were comparable between PwMS and controls. We found no effects of offline cerebellar anodal tDCS on locomotor adaptation and consolidation. Participants who received the active stimulation showed the same retention index than sham-stimulated subjects at T1 (p = 0.33) and T2 (p = 0.46).

Conclusion: Locomotor adaptation is preserved in people with mild-to-moderate MS. However, cerebellar anodal tDCS applied immediately post-training does not further enhance this ability. Future studies should define the neurobiological substrates of maintained plasticity in PwMS and how these substrates can be manipulated to improve compensation. Systematic assessments of methodological variables for cerebellar tDCS are urgently needed to increase the consistency and replicability of the results across experiments in various settings.

Development of a dynamic fall risk profile in elderly nursing home residents: A free field gait analysis based study

Falls in nursing home residents are associated with a significant individual and socioeconomic burden of disease. To trigger and tailor individual intervention programs, solid early detection measures of residents at risk are needed. Aim of this study was thus to test the capability of a free field gait analysis insole to determine its usefulness in determining fall risk. In an observational study gait data of 22 nursing home residents over the age of 75 years was collected over one week with a measuring insole. Clinical scores were performed at baseline (POMA; DGI, TUG). For 6 months before and after the insole measurement, the fall events per resident were recorded. Correlation analysis as well as receiver operating characteristic curve analysis were performed. The average resident age was 88.2 years (range 78-99), 15 had at least one fall event. There was no significant correlation between clinical assessment and fall risk. Moderate correlations between different temporospatial parameters and fall risk were seen. Pressure distribution during gait was markedly changed in fallers. Differences between fallers and non-fallers as well as cut off values for increased fall risk in the ROC analysis could be determined. The introduced measurement protocol suggests that patients at risk for falling can be detected without any additional office visits. Based on the introduced protocol in a limited patient setting, further large scale studies should now determine the effect of prevention measures triggered by gait analysis, the specific risk reduction and the associated personal and socioeconomic advantages.

Load-Bearing Detection with Insole-Force Sensors Provides New Treatment Insights in Fragility Fractures of the Pelvis

Background: Due to an aging society, more and more surgeons are confronted with fragility fractures of the pelvis (FFPs). The aim of treatment of such patients should be the quickest possible mobilization with full weight-bearing. Up to now however, there are no data on loading of the lower extremities in patients suffering FFPs. We hypothesized to find differences in loading of the lower limbs. Methods: 22 patients with a mean age of 84.1 years were included. During gait analysis with insole-force sensors, loading on the lower extremities was recorded during early mobilization after index fracture. Results: Especially the average peak force showed differences in loading, as the affected limb was loaded significantly less {59.78% (SD ± 16.15%) of the bodyweight vs. 73.22% (SD ± 14.84%) (p = <0.001, effect size r = 0.58)}. Furthermore, differences in loading in between the fracture patterns of FFPs were observed. Conclusion: This study shows that it is possible to reliably detect the extremity load, with the help of an insole device, in patients presenting with fragility fractures of the pelvis. There is great potential to improve the choice and time of treatment with insole-force sensors in FFPs in future.

Stabilization of a Type B1.1 Injury in a Morbidly Obese Patient Using an Internal Fixator in a Minimally Invasive Technique: A Case Report

CASE

In this case report, we present a novel stabilization technique of the pubic symphysis using an internal spinal fixator in a 78-year-old morbidly obese woman having a pelvic disruption type B1.1 (AO classification). We treated the disruption using an internal fixator to reduce the extent of the incision and soft-tissue damage.

CONCLUSIONS

The use of an internal fixator, known from percutaneous spinal fixation, for the stabilization of the pubic symphysis in cases of disruption ("open book" injuries) may be an alternative to the standard plate fixation as a novel minimally invasive stabilization technique.

Effect of investigator observation on gait parameters in individuals with stroke

Improvements in gait speed following various training paradigms applied to patients post-stroke does not always lead to changes in walking performance, defined as gains in daily stepping activity. We hypothesized that testing conditions, specifically the presence of an observer, influences patient behaviors and resultant outcomes may overestimate their true walking capacity. This potential Hawthorne effect on spatiotemporal and biomechanical measures of locomotor function in individuals post-stroke has not been assessed previously. Fifteen ambulatory individuals with chronic stroke wore instrumented insoles and performed two separate normal-pace walking assessments, including unobserved conditions during which participants were unattended and unaware of data collection, and observed conditions with an investigator present. Gait analysis was conducted outside of a laboratory setting using instrumented insoles equipped with a 3D accelerometer and pressure sensors which captured the spatiotemporal kinematics, vertical ground reaction forces and foot acceleration. Data were compared using paired comparisons, with subsequent correlation and stepwise regression analyses to explore potential associations between Hawthorne-induced changes in walking strategies, gait speed and locomotor performance (daily stepping). Except for cadence, other measures of spatiotemporal parameters and swing kinematics (acceleration) were not significantly different between observed vs unobserved conditions. However, analyses of ground reaction forces revealed significantly greater paretic limb loading (Δ1^st peak = 1.5 ± 1.6 N/kg Δ2^nd peak = 1.4 ± 1.8 N/kg; p < 0.01) and increases in weight bearing symmetry (11-24%, p < 0.01) during observed vs unobserved conditions. This potential Hawthorne effect was greater in those with slower walking speeds and shorter stride lengths but was not related to daily stepping. The present findings suggest that biomechanical parameters of walking function may be related to the presence of an observer and highlight the need to separately measure locomotor capacity (gait speed) and performance (daily stepping).

Weight bearing in patients with femoral neck fractures compared to pertrochanteric fractures: A postoperative gait analysis

Early mobilization following hip fracture surgery is of superior importance especially in elderly hip fracture patients. Reduced mobilization can result in complications and increased mortality. In this study a gait analysis was performed using force-measuring insoles. We hypothesized, that patients with femoral neck fractures treated with hip replacement surgery load the affected limb more compared to patients with pertrochanteric fractures treated with fracture fixation. All patients (> 65 years) treated for a femoral neck fracture with hip replacement or a pertrochanteric fracture, respectively using fracture fixation with intramedullary nailing, were consecutively included in this study. For gait analysis, specific insole forcesensors (Loadsol®) were inserted into the footwear. Five days after surgery gait analysis was performed with a defined walking distance and all patients were instructed to transpose full weight. 20 patients following hip replacement surgery and 27 patients following intramedullary nailing were included. The hip replacement group loaded the affected limb with an average of 74.01% (SD 13.6) of bodyweight, while the fracture fixation group loaded a significantly reduced average of 62.70% (SD 8.3; p = 0.002). The results of the present study indicate that patients suffering from pertrochanteric fractures following fracture fixation are struggling to fully load the affected leg compared to patients suffering from femoral neck fractures treated with hip replacement surgery. The focus of further studies should concentrate on alternative analgesia and verify the cause of the observed difference in order to facilitate early full weight bearing especially in hip fracture patients following fracture fixation. The results indicate that in elderly patients, the fracture pattern and thus the surgical approach lead to a different weight bearing pattern. The primary therapeutic goal for elderly patients must be early mobilization at full weight bearing.

Development of a step counting algorithm using the ambulatory tibia load analysis system for tibia fracture patients

Introduction: Ambulation can be used to monitor the healing of lower extremity fractures. However, the ambulatory behavior of tibia fracture patients remains unknown due to an inability to continuously quantify ambulation outside of the clinic. The goal of this study was to design and validate an algorithm to assess ambulation in tibia fracture patients using the ambulatory tibial load analysis system during recovery, outside of the clinic.

[A new continuous gait analysis system for ankle fracture aftercare]

BACKGROUND

Correct aftercare following lower extremity fractures remains a controversial issue. Reliable, clinically applicable weight-bearing recommendations have not yet been defined. The aim of the current study was to establish a new gait analysis insole during physical therapy aftercare of ankle fractures to test patients' continuous, long-term compliance to partial weight-bearing restrictions and investigate whether patients can estimate their weight-bearing compliance.

MATERIALS AND METHODS

The postoperative gait of 14 patients after operative treatment of Weber B-type ankle fractures was monitored continuously for six weeks (OpenGO, Moticon GmbH, Munich). All patients were instructed and trained by physical therapists on how to maintain partial weight-bearing for this time. Discontinuous (three, six and twelve weeks) clinical (patient questionnaire, visual analogue pain score [VAS]) and radiographic controls were performed.

RESULTS

Despite the set weight-bearing limits, individual ranges for overall weight-bearing (range 5-107% of the contralateral side) and patient activity (range 0-366 min/day) could be shown. A good correlation between weight-bearing and pain was seen (r_s = -0.68; p = <0.0001). Patients significantly underestimated their weight-bearing time over the set limit (2.3 ± 1.4 min/day vs. real: 12.6 ± 5.9 min/day; p < 0.01).

CONCLUSIONS

Standardized aftercare protocols and repeated training alone cannot ensure compliance to postoperative partial weight-bearing. Patients unconsciously increased weight-bearing based on their pain level. This study shows that new, individual and possibly technology-assisted weight-bearing regimes are needed. The introduced measuring device is feasible to monitor and steer patient weight-bearing during future studies.

Training with biofeedback devices improves clinical outcome compared to usual care in patients with unilateral TKA: a systematic review

PURPOSE

Biofeedback following total knee arthroplasty (TKA) seems to be a feasible approach to improve rehabilitation, outcomes, mobility and reduce pain. This systematic review gives the practicing orthopedic surgeon a summary of what is available and how biofeedback affects clinical outcomes.

METHODS

We reviewed the current literature regarding methods, devices and effects of biofeedback in patients who underwent total knee arthroplasty. Embase, Pubmed, Web of Science, and Cochrane Central Register of Controlled Trials were searched from inception to May 2018 for the following keywords: Biofeedback OR Feedback AND Total Knee Arthroplasty OR TKA. Data were extracted according to a predefined setting (see Protocol for systematic review on PROSPEO). Devices used for biofeedback were recorded. Demographics, training methods and effects were also collected.

RESULTS

The search resulted in 380 potentially eligible studies from which 11 met all inclusion criteria including 7 randomized controlled trials (RCTs), 3 cohort studies, and 1 cross-sectional study. A total of 416 patients with unilateral TKA were included, with an average of 37.8 patients per study. In patients with TKA, significant improvements in activity scores or pain were reported by 9 of 11 studies. Only two of the studies reported no significant influence of the feedback on the chosen outcome parameters. Devices for biofeedback varied between studies and included the use of a goniometer, force plate, balance board, treadmill, and/or electromyography (EMG). The most common type of feedback was visual followed by audio, with one study mentioning that the audio mode was preferred by the patients as it was easier to handle. Overall, 5 out of 6 different methods demonstrated a potential value for improving mobility and decreasing pain.

CONCLUSIONS

This review suggests that biofeedback in early postoperative rehabilitation after TKA is effective in improving gait symmetry, reducing pain and increasing activity level. It should be noted that the great variety of devices used for feedback limits comparisons between studies.

LEVEL OF EVIDENCE

IIa.

High Plantar Force Loading After Achilles Tendon Rupture Repair With Early Functional Mobilization

BACKGROUND

Mechanical loading is essential for tendon healing and may explain variability in patient outcomes after Achilles tendon rupture (ATR) repair. However, there is no consensus regarding the optimal postoperative regimen, and the actual amount of loading during orthosis immobilization is unknown.

PURPOSE

The primary aim of this study was to assess the number of steps and the amount of loading in a weightbearing orthosis during the first 6 weeks after surgical ATR repair. A secondary purpose was to investigate if the amount of loading was correlated to fear of movement and/or experience of pain.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Thirty-four patients (mean ± SD age, 38.8 ± 8.7 years) with ATR repair were included. Early functional mobilization was allowed postoperatively in an orthosis with adjustable ankle range of motion. During the first postoperative 2 weeks, patient-reported loading and pain were assessed with a visual analog scale and step counts with a pedometer. At the 2- and 6-week follow-up, a mobile force sensor was used for measuring plantar force loading, and the Tampa Scale for Kinesiophobia was used to examine fear of movement.

RESULTS

Between the first and second weeks, there was a significant increase in the mean number of daily steps taken (from 2025 to 2753, P < .001) as well as an increase in self-reported loading (from 20% to 53%, P < .001). Patient self-reported loading was significantly associated with the plantar force measurement (rho = 0.719, P < .001). At 6 weeks, loading was 88.2% on the injured limb versus the uninjured limb. Fear of movement was not correlated with pedometer data, subjective loading, pain, or force data. Patients with less pain during activity, however, reported significantly higher subjective load and took more steps ( P < .05).

CONCLUSION

This is the first study to demonstrate the actual loading patterns during postoperative functional mobilization among patients with surgically repaired ATR. The quick improvements in loading magnitude and frequency observed may reflect improved tendon loading essential for healing. Pain, rather than fear of movement, was associated with the high variability in loading parameters. The data of this study may be used to improve ATR rehabilitation protocols for future studies.

REGISTRATION

NCT02318472 (ClinicalTrials.gov).

Should I Stay or Should I Go? A Prospective, Blinded Study Comparing the Diagnostic Capability of Dynamic and Stationary Pedobarography in Plantar Fasciitis

The aim of this study was to determine the diagnostic capability of a dynamic gait analysis insole and compare its ability to detect clinical correlations to a common stationary analysis tool. Twenty-five patients with chronic plantar fasciitis were included in this prospective, blinded, diagnostic study. Conventional, stationary gait analysis on a force plate on an even surface and continuous dynamic pedobarography on a standardized course consisting of different gait tasks were performed and correlated to the disease severity. Mean patient age was 53.6 (range 41 to 68) years, with a mean pain level of 6.1 (range 4 to 10) on the Visual Analogue Scale and a calcaneodynia score of 48.7 (range 33 to 66). Significant correlations were seen between several dynamic gait values and clinical scoring: cadence (r_s = 0.56, p = .004), stance time (r_s = -0.6, p = .002), center-of-pressure velocity (r_s = 0.44, p = .046), and double support time (r_s = 0.42, p = .042). No significant correlations were seen between any force plate gait analysis values and clinical scoring. In this study setting, dynamic gait analysis was able to identify clinically relevant correlations to plantar fasciitis disease severity that standard force plate measurements could not.

The relationship between gait and functional outcomes in patients treated with circular external fixation for malunited tibial fractures

BACKGROUND

Lower extremity fractures have a profound negative effect on a patient's gait and outcomes. Correction of deformity, and with it normalization of objective gait parameters, may result in better subjective and objective functional outcomes in patients treated with circular external fixation for malunited tibial fractures.

AIM

The purpose of this study was to investigate the relationships between gait parameters, patient reported outcome measures (PROMs), and health related quality of life measures in patients treated with circular external fixation for the correction of deformity related to tibial malunions.

METHODS

This retrospective study included patients with posttraumatic tibial deformities, aged 14-65, with a minimum follow-up of 24 months following deformity correction. Patients with congenital deformities, head injuries, spinal cord injury, neurological disorders, or contralateral lower limb amputation were excluded. Functional outcomes were assessed by the Foot Function Index (FFI); Short Form 12 (SF-12); the EQ 5D; and the ASAMI score. Gait analysis was performed using Dartfish® and the Edinburgh Visual Gait Score (EVGS). The relationships between the EVGS and functional outcome scores were analyzed using Pearsons' moment correlations with Bonferroni corrections.

RESULTS

Eleven patients with a mean age of 42 (range 23-57) were analyzed. The mean EVGS was 2.6 ± 2.1, the mean FFI 29.6 ± 33.4, the mean EQ5 Index Value 0.7 ± 0.2, the mean EQ5 VAS 85.4 ± 19.5, the SF12 mean Physical Component Score (PCS) 46.7 ± 11.1, and the mean Mental Component Score (MCS) 55.2 ± 7.5. The following relationships were strong and significant: EVGS and FFI (r = 0.7; P = 0.02), EVGS and PCS (r = -0.82; P = 0.02), and FFI and EQ5 (r = -0.79, P = 0.05).

SIGNIFICANCE

The results of this study suggest that correction of deformity with realignment and restoration of normal anatomy was associated with improved functional outcomes and physical well-being. Patient reported quality of life is strongly associated with patient perceived functional outcome, but not with objective gait parameters.

Inability of Older Adult Patients with Hip Fracture to Maintain Postoperative Weight-Bearing Restrictions

BACKGROUND

For elderly trauma patients, a basic goal is early mobilization, as immobilization can trigger various complications, such as venous thromboembolism, pneumonia, urinary tract infections, and pressure ulcers. Although partial weight-bearing has been shown to significantly increase mortality compared with unrestricted weight-bearing, it remains a frequent recommendation of aftercare following lower-extremity fracture fixation.

METHODS

An insole force sensor was used to measure true postoperative weight-bearing by patients ≥75 years of age treated for hip fracture compared with patients 18 to 40 years of age treated for ankle fracture. Both groups were instructed to maintain partial weight-bearing on the affected limb (≤20 kg) postoperatively. Following standardized physiotherapy training, gait analysis was performed.

RESULTS

None of the patients in the elderly test group were able to comply with the weight-bearing restriction as recommended. We found that 69% (11 of 16) of the patients exceeded the specified load by more than twofold, whereas significantly more patients in the younger control group (>75% [14 of 18]) achieved almost the entire weight-bearing restriction (p < 0.001). Only 1 of the elderly patients was able to comply with the predetermined weight-bearing restriction, and only for a short period of time. In comparison, significantly more patients in the control group (89% [16 of 18]; p < 0.001) maintained the partial load for nearly the entire time during gait analysis.

CONCLUSIONS

Elderly patients seem to be unable to maintain weight-bearing restrictions. As early mobilization of geriatric trauma patients is an important element for a successful rehabilitation, the directive of postoperative partial weight-bearing for these patients should be abandoned.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Mobile gait analysis via eSHOEs instrumented shoe insoles: a pilot study for validation against the gold standard GAITRite®

Clinical gait analysis contributes massively to rehabilitation support and improvement of in-patient care. The research project eSHOE aspires to be a useful addition to the rich variety of gait analysis systems. It was designed to fill the gap of affordable, reasonably accurate and highly mobile measurement devices. With the overall goal of enabling individual home-based monitoring and training for people suffering from chronic diseases, affecting the locomotor system. Motion and pressure sensors gather movement data directly on the (users) feet, store them locally and/or transmit them wirelessly to a PC. A combination of pattern recognition and feature extraction algorithms translates the motion data into standard gait parameters. Accuracy of eSHOE were evaluated against the reference system GAITRite in a clinical pilot study. Eleven hip fracture patients (78.4 ± 7.7 years) and twelve healthy subjects (40.8 ± 9.1 years) were included in these trials. All subjects performed three measurements at a comfortable walking speed over 8 m, including the 6-m long GAITRite mat. Six standard gait parameters were extracted from a total of 347 gait cycles. Agreement was analysed via scatterplots, histograms and Bland-Altman plots. In the patient group, the average differences between eSHOE and GAITRite range from -0.046 to 0.045 s and in the healthy group from -0.029 to 0.029 s. Therefore, it can be concluded that eSHOE delivers adequately accurate results. Especially with the prospect as an at home supplement or follow-up to clinical gait analysis and compared to other state of the art wearable motion analysis systems.

Predictive value of clinical scoring and simplified gait analysis for acetabulum fractures

BACKGROUND

Fractures of the acetabulum show a high, long-term complication rate. The aim of the present study was to determine the predictive value of clinical scoring and standardized, simplified gait analysis on the outcome after these fractures.

METHODS

Forty-one patients with acetabular fractures treated between 2008 and 2013 and available, standardized video recorded aftercare were identified from a prospective database. A visual gait score was used to determine the patients walking abilities 6-m postoperatively. Clinical (Merle d'Aubigne and Postel score, visual analogue scale pain, EQ5d) and radiological scoring (Kellgren-Lawrence score, postoperative computed tomography, and Matta classification) were used to perform correlation and multivariate regression analysis.

RESULTS

The average patient age was 48 y (range, 15-82 y), six female patients were included in the study. Mean follow-up was 1.6 y (range, 1-2 y). Moderate correlation between the gait score and outcome (versus EQ5d: r_s = 0.477; versus Merle d'Aubigne: r_s = 0.444; versus Kellgren-Lawrence: r_s = -0.533), as well as high correlation between the Merle d'Aubigne score and outcome were seen (versus EQ5d: r_s = 0.575; versus Merle d'Aubigne: r_s = 0.776; versus Kellgren-Lawrence: r_s = -0.419). Using a multivariate regression model, the 6 m gait score (B = -0.299; P < 0.05) and early osteoarthritis development (B = 1.026; P < 0.05) were determined as predictors of final osteoarthritis. A good fit of the regression model was seen (R² = 904).

CONCLUSIONS

Easy and available clinical scoring (gait score/Merle d'Aubigne) can predict short-term radiological and functional outcome after acetabular fractures with sufficient accuracy. Decisions on further treatment and interventions could be based on simplified gait analysis.