scholarly journals A Nonproprietary Movement Analysis System (MoJoXlab) Based on Wearable Inertial Measurement Units Applicable to Healthy Participants and Those With Anterior Cruciate Ligament Reconstruction Across a Range of Complex Tasks: Validation Study (Preprint)

2020 ◽  
Author(s):  
Riasat Islam ◽  
Mohamed Bennasar ◽  
Kevin Nicholas ◽  
Kate Button ◽  
Simon Holland ◽  
...  

BACKGROUND Movement analysis in a clinical setting is frequently restricted to observational methods to inform clinical decision making, which has limited accuracy. Fixed-site, optical, expensive movement analysis laboratories provide <i>gold standard</i> kinematic measurements; however, they are rarely accessed for routine clinical use. Wearable inertial measurement units (IMUs) have been demonstrated as comparable, inexpensive, and portable movement analysis toolkits. MoJoXlab has therefore been developed to work with generic wearable IMUs. However, before using MoJoXlab in clinical practice, there is a need to establish its validity in participants with and without knee conditions across a range of tasks with varying complexity. OBJECTIVE This paper aimed to present the validation of MoJoXlab software for using generic wearable IMUs for calculating hip, knee, and ankle joint angle measurements in the sagittal, frontal, and transverse planes for walking, squatting, and jumping in healthy participants and those with anterior cruciate ligament (ACL) reconstruction. METHODS Movement data were collected from 27 healthy participants and 20 participants with ACL reconstruction. In each case, the participants wore seven MTw2 IMUs (Xsens Technologies) to monitor their movement in walking, jumping, and squatting tasks. The hip, knee, and ankle joint angles were calculated in the sagittal, frontal, and transverse planes using two different software packages: Xsens’ validated proprietary MVN Analyze and MoJoXlab. The results were validated by comparing the generated waveforms, cross-correlation (CC), and normalized root mean square error (NRMSE) values. RESULTS Across all joints and activities, for data of both healthy and ACL reconstruction participants, the CC and NRMSE values for the sagittal plane are 0.99 (SD 0.01) and 0.042 (SD 0.025); 0.88 (SD 0.048) and 0.18 (SD 0.078) for the frontal plane; and 0.85 (SD 0.027) and 0.23 (SD 0.065) for the transverse plane (hip and knee joints only). On comparing the results from the two different software systems, the sagittal plane was very highly correlated, with frontal and transverse planes showing strong correlation. CONCLUSIONS This study demonstrates that nonproprietary software such as MoJoXlab can accurately calculate joint angles for movement analysis applications comparable with proprietary software for walking, squatting, and jumping in healthy individuals and those following ACL reconstruction. MoJoXlab can be used with generic wearable IMUs that can provide clinicians accurate objective data when assessing patients’ movement, even when changes are too small to be observed visually. The availability of easy-to-setup, nonproprietary software for calibration, data collection, and joint angle calculation has the potential to increase the adoption of wearable IMU sensors in clinical practice, as well as in free living conditions, and may provide wider access to accurate, objective assessment of patients’ progress over time.


10.2196/17872 ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. e17872
Author(s):  
Riasat Islam ◽  
Mohamed Bennasar ◽  
Kevin Nicholas ◽  
Kate Button ◽  
Simon Holland ◽  
...  

Background Movement analysis in a clinical setting is frequently restricted to observational methods to inform clinical decision making, which has limited accuracy. Fixed-site, optical, expensive movement analysis laboratories provide gold standard kinematic measurements; however, they are rarely accessed for routine clinical use. Wearable inertial measurement units (IMUs) have been demonstrated as comparable, inexpensive, and portable movement analysis toolkits. MoJoXlab has therefore been developed to work with generic wearable IMUs. However, before using MoJoXlab in clinical practice, there is a need to establish its validity in participants with and without knee conditions across a range of tasks with varying complexity. Objective This paper aimed to present the validation of MoJoXlab software for using generic wearable IMUs for calculating hip, knee, and ankle joint angle measurements in the sagittal, frontal, and transverse planes for walking, squatting, and jumping in healthy participants and those with anterior cruciate ligament (ACL) reconstruction. Methods Movement data were collected from 27 healthy participants and 20 participants with ACL reconstruction. In each case, the participants wore seven MTw2 IMUs (Xsens Technologies) to monitor their movement in walking, jumping, and squatting tasks. The hip, knee, and ankle joint angles were calculated in the sagittal, frontal, and transverse planes using two different software packages: Xsens’ validated proprietary MVN Analyze and MoJoXlab. The results were validated by comparing the generated waveforms, cross-correlation (CC), and normalized root mean square error (NRMSE) values. Results Across all joints and activities, for data of both healthy and ACL reconstruction participants, the CC and NRMSE values for the sagittal plane are 0.99 (SD 0.01) and 0.042 (SD 0.025); 0.88 (SD 0.048) and 0.18 (SD 0.078) for the frontal plane; and 0.85 (SD 0.027) and 0.23 (SD 0.065) for the transverse plane (hip and knee joints only). On comparing the results from the two different software systems, the sagittal plane was very highly correlated, with frontal and transverse planes showing strong correlation. Conclusions This study demonstrates that nonproprietary software such as MoJoXlab can accurately calculate joint angles for movement analysis applications comparable with proprietary software for walking, squatting, and jumping in healthy individuals and those following ACL reconstruction. MoJoXlab can be used with generic wearable IMUs that can provide clinicians accurate objective data when assessing patients’ movement, even when changes are too small to be observed visually. The availability of easy-to-setup, nonproprietary software for calibration, data collection, and joint angle calculation has the potential to increase the adoption of wearable IMU sensors in clinical practice, as well as in free living conditions, and may provide wider access to accurate, objective assessment of patients’ progress over time.



Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 141 ◽  
Author(s):  
Rob Van der Straaten ◽  
Amber K. B. D. Bruijnes ◽  
Benedicte Vanwanseele ◽  
Ilse Jonkers ◽  
Liesbet De Baets ◽  
...  

This study evaluates the reliability and agreement of the 3D range of motion (ROM) of trunk and lower limb joints, measured by inertial measurement units (MVN BIOMECH Awinda, Xsens Technologies), during a single leg squat (SLS) and sit to stand (STS) task. Furthermore, distinction was made between movement phases, to discuss the reliability and agreement for different phases of both movement tasks. Twenty healthy participants were measured on two testing days. On day one, measurements were conducted by two operators to determine the within-session and between-operator reliability and agreement. On day two, measurements were conducted by the same operator, to determine the between-session reliability and agreement. The SLS task had lower within-session reliability and agreement compared with between-session and between-operator reliability and agreement. The reliability and agreement of the hip, knee, and ankle ROM in the sagittal plane were good for both phases of the SLS task. For both phases of STS task, within-session reliability and agreement were good, and between-session and between-operator reliability and agreement were lower in all planes. As both tasks are physically demanding, differences may be explained by inconsistent movement strategies. These results show that inertial sensor systems show promise for use in further research to investigate (mal)adaptive movement strategies.



2018 ◽  
Vol 6 (1) ◽  
pp. 232596711775081 ◽  
Author(s):  
Yoshinari Tanaka ◽  
Keisuke Kita ◽  
Rikio Takao ◽  
Hiroshi Amano ◽  
Ryohei Uchida ◽  
...  

Background: It remains unclear whether the tibiofemoral relationship in the sagittal plane is restored after anatomic anterior cruciate ligament (ACL) reconstruction, particularly in cases of chronic ACL deficiency (ACLD). Hypothesis: Patients with long-term ACLD will exhibit an anteriorly subluxed tibia both preoperatively and immediately postoperatively, even after anatomic reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: In total, 358 patients who had undergone anatomic ACL reconstruction with autologous semitendinosus grafts were divided into 5 groups based on chronicity of ACLD: (1) 0 to 6 months, (2) 6 months to 1 year, (3) 1 to 2 years, (4) 2 to 5 years, and (5) longer than 5 years. Preoperatively and immediately postoperatively, all patients underwent lateral radiography in extension to evaluate the tibiofemoral relationship, specifically with regard to anterior tibial subluxation (ATS), space for the ACL (sACL), and extension angle. Demographic and radiographic factors were compared among the 5 groups. Results: Preoperative ATS values in groups 4 (mean ± SD, 2.9 ± 2.1 mm) and 5 (2.6 ± 1.9 mm) were significantly greater than in group 1 (1.6 ± 1.9 mm). Postoperatively, the tibia was posteriorly overconstrained in all groups, and there was no difference in immediately postoperative ATS among the 5 groups. Further evaluation of the tibiofemoral relationship in the sagittal plane revealed that the mean preoperative side-to-side difference in sACL (sACL-SSD) was greater in groups 4 (2.5 ± 1.6 mm) and 5 (2.2 ± 1.7 mm) than in group 1 (1.2 ± 1.5 mm). Immediately after ACL reconstruction, however, there were no group-dependent differences in sACL-SSD. No significant group-dependent differences were found for extension deficit. Conclusion: Chronicity of ACLD had an effect on the preoperative tibiofemoral relationship in the sagittal plane, including ATS and sACL-SSD, especially in patients with ACLD longer than 2 years. However, preoperative extension deficit was not influenced by chronicity. Immediately postoperatively, chronicity did not affect the ability of anatomic ACL reconstruction to reduce subluxation.



2013 ◽  
Vol 35 (2) ◽  
pp. 237 ◽  
Author(s):  
Tamires Lisboa Tellini ◽  
Karina Oliveira Lima ◽  
Sandra Regina Alouche ◽  
Leia Bernardi Bagesteiro

Previous studies of gait analysis in patients following reconstructive anterior cruciate ligament (ACL) surgery have shown changes in kinematics, kinetics and energy patterns in the lower limb. Usually these patients perform complaint surface training during clinical treatment. The purpose of this study was to evaluate the changes in selected gait kinematic parameters following ACL reconstruction while walking on an unstable surface. We tested 16 subjects: eight patients who underwent ACL reconstruction, at four weeks after the surgical intervention; and eight healthy subjects (control group) matched by age and gender. Participants walked at a self-selected comfortable speed on an 8 m-walkway while sagittal plane kinematic data of the principal lower limb joints (hip, knee and ankle) were collected using 60-Hz cameras. We compared the joint angles under three conditions: (A) walking on stable ground, (B) walking on a foam mat (5 cm thick; 33 kg m-3 density) and (C) back at the normal ground. Results showed that ACL patients were slower and had smaller range of motion at all joints as compared to the control group under all conditions; however the repeated exposure to unstable surface may help changes in such patients. Further investigation is necessary to expand our understanding and may improve the development of more effective rehabilitation treatments.  



2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0008
Author(s):  
D.Landry Jarvis ◽  
Danica D. Vance ◽  
Jonathan C. Riboh

Background: Transphyseal anterior cruciate ligament (ACL) reconstruction remains the most commonly used technique for pubescent patients. The principles of creating vertical and central femoral tunnels are well accepted to minimize physeal area of injury and are typically accomplished with a transtibial (TT) technique. This, however, may come at the expense of a non-anatomic tunnel. The hybrid transtibial (HTT) technique offers the potential of combining an anatomic femoral position with tunnel geometry similar to the TT technique but has never been assessed in a clinical cohort. Hypothesis/Purpose: We hypothesized that tunnels created by a HTT technique would be similar in orientation and physeal location to TT tunnels, but significantly more vertical and central than tunnels created with an anteromedial portal (AM). Methods: We retrospectively screened all ACL reconstructions performed in children aged 10 to 16 years, at our institution between 2013 to 2019, with the requirements of having a transphyseal reconstruction and an available post-operative radiographs. Radiographs were then assessed for the coronal femoral tunnel angle (FTA), as well as the location of the tunnel-physis penetration on the AP (LTAP) and lateral (LTL) views. Physeal lesion surface area was calculated. Data were compared between the three groups using ANOVA. Results: Forty-seven patients met eligibility criteria with 9 TT, 18 AM, and 20 HTT patients. Mean patient age was 14.3 +/- 1.2 years. The FTA was significantly more vertical in the TT (60.7o +/-7.2) and HTT (54.4o +/- 5.7) groups as compared to the AM group (48.8o +/- 5.9); p = 0.0037 and p = 0.02 respectively. There was no significant difference between the TT and HTT groups ( p = 0.066). The LTAP was not significantly different between groups (p = 0.097). The LTL demonstrated that the HTT tunnels penetrated the physis at a more central location in the sagittal plane (28.9% +/- 4.8%) than the AM tunnels (20.0% +/- 5.1%, p = 0.00002), but was statistically indistinguishable from the TT (24.4%+/- 4.0%, p= 0.066) tunnels. Conclusion: The hybrid transtibial technique presents an option for transphyseal ACL reconstruction, with femoral tunnel obliquity and estimated physeal disruption similar to the TT technique, significantly less than the AM technique. The HTT also results in the most central physeal perforation of all techniques, predominantly in the sagittal plane. With the known ability of the HTT technique to recreate an anatomic femoral footprint, this may represent the “best of both worlds” for transphyseal ACL reconstruction. Tables/Figures: [Figure: see text][Figure: see text][Figure: see text][Figure: see text]



2021 ◽  
pp. 194173812110049
Author(s):  
Riann M. Palmieri-Smith ◽  
Michael T. Curran ◽  
Steven A. Garcia ◽  
Chandramouli Krishnan

Background: Biomechanical knee asymmetry is commonly present after anterior cruciate ligament (ACL) reconstruction. Factors that could assist in identification of asymmetrical biomechanics after ACL reconstruction could help clinicians in making return-to-play decisions. The purpose of this study is to determine factors that may contribute to knee biomechanical asymmetry present after ACL reconstruction. Hypothesis: We hypothesized that quadriceps strength and activation and patient-reported function would allow for identification of patients with symmetrical knee biomechanics. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: Thirty-one subjects (18 women; time since ACL reconstruction = 284.4 ± 53.6 days) who underwent ACL reconstruction and were to return to activity were recruited. Participants completed bilateral assessments of isokinetic quadriceps strength, quadriceps activation using the superimposed burst technique, and biomechanical function testing during a single-leg forward hop. The International Knee Documentation Committee (IKDC) subjective knee form was also completed. Symmetry values were calculated for each variable. Decision trees were utilized to determine which input factors (quadriceps strength symmetry, quadriceps activation symmetry, IKDC score, age, sex, height, mass, graft type) were able to identify participants who had symmetrical knee flexion angles (KFAs) and extension moments. Angles and moments were considered symmetrical if symmetry values were ≥90%. Results: Quadriceps strength and activation symmetry were able to predict whether a patient landed with symmetrical or asymmetrical KFAs, with thresholds of 77.2% strength symmetry and 91.3% activation symmetry being established. Patient-reported function and quadriceps strength were factors that allowed for classification of participants with symmetrical/asymmetrical knee extension moments, with thresholds of 89.1 for the IKDC and 80.0% for quadriceps strength symmetry. Conclusions: Quadriceps strength contributed to both models and appears to be a critical factor for achieving symmetrical knee biomechanics. High patient-reported function and quadriceps activation are also important for restoring knee biomechanical symmetry after ACL reconstruction. Clinical Relevance: Quadriceps strength and activation and patient-reported function may be able to assist clinicians in identifying ACL patients with symmetrical/asymmetrical knee biomechanics.



Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 652
Author(s):  
Sangheon Park ◽  
Sukhoon Yoon

Patients experience various biomechanical changes following reconstruction for anterior cruciate ligament (ACL) injury. However, previous studies have focused on lower extremity joints as a single joint rather than simultaneous lower extremity movements. Therefore, this study aimed to determine the movement changes in the lower limb coordination patterns according to movement type following ACL reconstruction. Twenty-one post ACL reconstruction patients (AG) and an equal number of healthy adults (CG) participated in this study. They were asked to perform walking, running, and cutting maneuvers. The continuous relative phase and variability were calculated to examine the coordination pattern. During running and cutting at 30 and 60°, the AG demonstrated a lower in-phase hip–knee coordination pattern in the sagittal plane. The AG demonstrated low hip–knee variability in the sagittal plane during cutting at 60°. The low in-phase coordination pattern can burden the knee by generating unnatural movements following muscle contraction in the opposite direction. Based on the results, it would be useful to identify the problem and provide the fundamental evidence for the optimal timing of return-to-sport after ACL reconstruction (ACLR) rehabilitation, if the coordination variable is measured with various sensors promptly in the sports field to evaluate the coordination of human movement.



Author(s):  
Willem M.P. Heijboer ◽  
Mathijs A.M. Suijkerbuijk ◽  
Belle L. van Meer ◽  
Eric W.P. Bakker ◽  
Duncan E. Meuffels

AbstractMultiple studies found hamstring tendon (HT) autograft diameter to be a risk factor for anterior cruciate ligament (ACL) reconstruction failure. This study aimed to determine which preoperative measurements are associated with HT autograft diameter in ACL reconstruction by directly comparing patient characteristics and cross-sectional area (CSA) measurement of the semitendinosus and gracilis tendon on magnetic resonance imaging (MRI). Fifty-three patients with a primary ACL reconstruction with a four-stranded HT autograft were included in this study. Preoperatively we recorded length, weight, thigh circumference, gender, age, preinjury Tegner activity score, and CSA of the semitendinosus and gracilis tendon on MRI. Total CSA on MRI, weight, height, gender, and thigh circumference were all significantly correlated with HT autograft diameter (p < 0.05). A multiple linear regression model with CSA measurement of the HTs on MRI, weight, and height showed the most explained variance of HT autograft diameter (adjusted R 2 = 44%). A regression equation was derived for an estimation of the expected intraoperative HT autograft diameter: 1.2508 + 0.0400 × total CSA (mm2) + 0.0100 × weight (kg) + 0.0296 × length (cm). The Bland and Altman analysis indicated a 95% limit of agreement of ± 1.14 mm and an error correlation of r = 0.47. Smaller CSA of the semitendinosus and gracilis tendon on MRI, shorter stature, lower weight, smaller thigh circumference, and female gender are associated with a smaller four-stranded HT autograft diameter in ACL reconstruction. Multiple linear regression analysis indicated that the combination of MRI CSA measurement, weight, and height is the strongest predictor.



2020 ◽  
Vol 11 (1) ◽  
pp. 130
Author(s):  
Datao Xu ◽  
Xinyan Jiang ◽  
Xuanzhen Cen ◽  
Julien S. Baker ◽  
Yaodong Gu

Volleyball players often land on a single leg following a spike shot due to a shift in the center of gravity and loss of balance. Landing on a single leg following a spike may increase the probability of non-contact anterior cruciate ligament (ACL) injuries. The purpose of this study was to compare and analyze the kinematics and kinetics differences during the landing phase of volleyball players using a single leg (SL) and double-leg landing (DL) following a spike shot. The data for vertical ground reaction forces (VGRF) and sagittal plane were collected. SPM analysis revealed that SL depicted a smaller knee flexion angle (about 13.8°) and hip flexion angle (about 10.8°) during the whole landing phase, a greater knee and hip power during the 16.83–20.45% (p = 0.006) and 13.01–16.26% (p = 0.008) landing phase, a greater ankle plantarflexion angle and moment during the 0–41.07% (p < 0.001) and 2.76–79.45% (p < 0.001) landing phase, a greater VGRF during the 5.87–8.25% (p = 0.029), 19.75–24.14% (p = 0.003) landing phase when compared to DL. Most of these differences fall within the time range of ACL injury (30–50 milliseconds after landing). To reduce non-contact ACL injuries, a landing strategy of consciously increasing the hip and knee flexion, and plantarflexion of the ankle should be considered by volleyball players.



2021 ◽  
Vol 9 (2) ◽  
pp. 232596712098164
Author(s):  
Steven F. DeFroda ◽  
Devan D. Patel ◽  
John Milner ◽  
Daniel S. Yang ◽  
Brett D. Owens

Background: Anterior cruciate ligament (ACL) injury in National Basketball Association (NBA) players can have a significant impact on player longevity and performance. Current literature reports a high rate of return to play, but there are limited data on performance after ACL reconstruction (ACLR). Purpose/Hypothesis: To determine return to play and player performance in the first and second seasons after ACLR in NBA players. We hypothesized that players would return at a high rate. However, we also hypothesized that performance in the first season after ACLR would be worse as compared with the preinjury performance, with a return to baseline by postoperative year 2. Study Design: Case series; Level of evidence, 4. Methods: An online database of NBA athlete injuries between 2010 and 2019 was queried using the term ACL reconstruction. For the included players, the following data were recorded: name; age at injury; position; height, weight, and body mass index; handedness; NBA experience; dates of injury, surgery, and return; knee affected; and postoperative seasons played. Regular season statistics for 1 preinjury season and 2 postoperative seasons were compiled and included games started and played, minutes played, and player efficiency rating. Kaplan-Meier survivorship plots were computed for athlete return-to-play and retirement endpoints. Results: A total of 26 athletes underwent ACLR; of these, 84% (95% CI, 63.9%-95.5%) returned to play at a mean 372.5 days (95% CI, 323.5-421.5 days) after surgery. Career length after injury was a mean of 3.36 seasons (95% CI, 2.27-4.45 seasons). Factors that contributed to an increased probability of return to play included younger age at injury (odds ratio, 0.71 [95% CI, 0.47-0.92]; P = .0337) and fewer years of experience in the NBA before injury (odds ratio, 0.70 [95% CI, 0.45-0.93]; P = .0335). Postoperatively, athletes played a significantly lower percentage of total games in the first season (48.4%; P = .0004) and second season (62.1%; P = .0067) as compared with the preinjury season (78.5%). Player efficiency rating in the first season was 19.3% less than that in the preinjury season ( P = .0056). Performance in the second postoperative season was not significantly different versus preinjury. Conclusion: NBA players have a high rate of RTP after ACLR. However, it may take longer than a single season for elite NBA athletes to return to their full preinjury performance. Younger players and those with less NBA experience returned at higher rates.



Sign in / Sign up

Export Citation Format

Share Document