Muscle dynamics analysis by clustered categories during jogging in patients with anterior cruciate ligament deficiency.

BACKGROUND: Patients with anterior cruciate ligament (ACL) deficiency (ACLD) tend to have altered lower extremity dynamics. Little is known about the changes in dynamic function and activation during jogging in patients with ACLD. METHODS: Twenty patients with an injured ACL before ACL reconstruction (ACLD group) and nine healthy male volunteers (control group) were recruited. Each volunteer repeated the jogging experiment five times. Based on the experimental data measured, a musculoskeletal multibody dynamics model was employed to simulate the tibiofemoral joint dynamics during jogging. Eighteen muscles were used for analysis. The obtained dynamics data were used for clustering and curve difference analysis. RESULTS: The 18 muscles studied were divided into 3 categories. All the quadriceps, the soleus, the gastrocnemius, and the popliteus were classified as label 1. All the hamstrings were classified as label 2, and the sartorius muscles were classified as label 3. Among them, the classification of the short head of the biceps femoris was significantly different between the two groups (P < 0.001). The force curves of all 18 muscles and the between-group differences were studied according to clustered categories. Most muscle force in label 1 was approaching zero in the terminal stance phase, which was significantly lower than that in the control group (P < 0.05). The muscle force in label 2 had areas with significant differences in the stance phase. Muscle force in label 3 was significantly lower than that in the control group in the pre-swing phase. CONCLUSIONS: This study showed that there are various changes of muscle function and activation in patients with ACLD. Through clustering and curve analysis, the joint reactions and changes of different muscle forces in the gait cycle between the ACLD and control groups could be further clarified.

[Effect of anterior cruciate ligament rupture on hamstring: quadriceps ratio during isokinetic knee extension and flexion at 30 degrees of flexion].

OBJECTIVE: To evaluate the change in hamstring (H):quadriceps (Q) ratio following anterior cruciate ligament (ACL) rupture during isokinetic knee extension and flexion at 30 degrees of flexion which is important for knee dynamic function. METHODS: A study was performed in 25 male complete unilateral ACL ruptures. Isokinetic concentric and eccentric quadriceps and hamstring muscle tests in both the deficient knees and intact knees were performed at 60°/s, respectively. At 30 degrees of flexion, the average torque of quadriceps and hamstring, Qe:Qc ratios (ratios of eccentric quadriceps to concentric quadriceps muscle torque), He:Hc ratios (eccentric hamstring to concentric hamstring), Hc:Qc ratios (concentric hamstring to concentric quadriceps), He:Qc ratios (eccentric hamstring to concentric quadriceps), and Hc:Qe ratios (concentric hamstring to eccentric quadriceps) were calculated. Wilcoxon matched-pairs signed-ranks test was used. RESULTS: At 30 degrees of knee flexion, a significant reduction (P<0.05) in the average torque of quadriceps was observed at concentric and eccentric 60°/s produced by the deficient-side compared with the intact side. In addition, Hc:Qc, He:Qc, and Qe:Qc significantly increased on the ACL-deficient side. CONCLUSION: The change in H :Q ratio in the mode of isokinetic 60°/s at 30 degrees of knee flexion might therefore be a new tool to objectively document muscle function in ACL-deficient knee.

The relationship of peak ankle dorsiflexion angle with lower extremity biomechanics during walking.

PURPOSE: Abnormal lower limb movement patterns have been observed during walking in individuals with limited ankle dorsiflexion. The purpose of this study was to investigate the relationships of peak ankle dorsiflexion angle during the stance phase of walking with the lower extremity biomechanics at the corresponding moment and to determine a cutoff value of functional limited ankle dorsiflexion during walking. METHODS: Kinematic and kinetic data of 70 healthy participants were measured during walking. Spearman's correlation coefficients were calculated to establish the association between peak ankle dorsiflexion and angle and moment of ankle, knee, and hip, ground reaction force, and pelvic movement at peak ankle dorsiflexion. All variables significantly related to peak ankle dorsiflexion were extracted as a common factor by factor analysis. Maximally selected Wilcoxon statistic was used to perform a cutoff value analysis. RESULTS: Peak ankle dorsiflexion positively correlated with ankle plantar flexion moment (r = 0.432; p = 0.001), ankle external rotation moment (r = 0.251; p = 0.036), hip extension angle (r = 0.281; p = 0.018), hip flexion moment (r = 0.341; p = 0.004), pelvic ipsilateral rotation angle (r = 0.284; p = 0.017), and medial, anterior, and vertical ground reaction force (r = 0.324; p = 0.006, r = 0.543; p = 0.001, r = 0.322; p = 0.007), negatively correlated with knee external rotation angle (r = -0.394; p = 0.001) and hip adduction angle (r = -0.256; p = 0.032). The cutoff baseline value for all 70 participants was 9.03°. CONCLUSIONS: There is a correlation between the peak ankle dorsiflexion angle and the lower extremity biomechanics during walking. If the peak ankle dorsiflexion angle is less than 9.03°, the lower limb movement pattern will change significantly.

Epidemiology of Lateral Patellar Dislocation Including Bone Bruise Incidence: Five Years of Data from a Trauma Center.

OBJECTIVE: Systematic summary of the epidemiology of patellar dislocation is rare. This study aims to investigate sex-, age-, type-, injury causing events-, incidence of bone bruise and time from last injury (TFLI)-specific characteristics, and detail the epidemiological characteristics of patellar dislocation. METHOD: In this descriptive epidemiological study, a total of 743 patients who have a history of lateral patellar dislocation with either first-time patellar dislocation (FPD) or recurrent patellar dislocation (RPD) between August 2017 and June 2022 at our institution met the inclusion criteria and were selected in this study. Patient characteristics including the type, gender, age, events leading to patellar dislocation, incidence of patellar bone bruise, and the time from last injury (TFLI) of patellar dislocation were retrospectively obtained and described. Magnetic resonance imaging scans (MRI) of the knee were reviewed for insuring bone bruise. RESULTS: Among the 743 patients with patellar dislocation who required surgical reconstruction of the medial retinaculum, 418 (56.2%) had RPD and 325 (43.8%) had FPD. There were more females (65.0%) than males (35.0%) in patellar dislocation patients. Among the female patients, those aged <18 years had higher incidence (31.4%) of patellar dislocation. Among the male patients, those aged <18 and 19-28 years had higher incidence (16.8%) of patellar dislocation. Of all age groups, the prevalence rate of patellar dislocation was high in juvenile population and females, but with no statistical significance. The most common patellar dislocation-causing event was sport accidents (40.1%), followed by life accidents (23.2%). The incidence of left-knee patellar dislocation was slightly higher than that of right-knee patellar dislocation. The incidence of patellar bone bruise of RPD (63.2%) was significantly lower (p < 0.05) than that of FPD (82.2%). Patellar dislocation patients with bone bruise had shorter time from last injury (TFLI) than those without patellar bone bruise (p < 0.05). CONCLUSIONS: The incidence of bone bruise of RPD was lower than that of FPD, and patients with patellar bone bruise may have a shorter time from last injury than those without bone bruise.

Leveraging Multivariable Linear Regression Analysis to Identify Patients with Anterior Cruciate Ligament Deficiency Using a Composite Index of the Knee Flexion and Muscle Force.

Patients with anterior cruciate ligament (ACL) deficiency (ACLD) tend to have altered lower extremity kinematics and dynamics. Clinical diagnosis of ACLD requires more objective and convenient evaluation criteria. Twenty-five patients with ACLD before ACL reconstruction and nine healthy volunteers were recruited. Five experimental jogging data sets of each participant were collected and calculated using a musculoskeletal model. The resulting knee flexion and muscle force data were analyzed using a t-test for characteristic points, which were the time points in the gait cycle when the most significant difference between the two groups was observed. The data of the characteristic points were processed with principal component analysis to generate a composite index for multivariable linear regression. The accuracy rate of the regression model in diagnosing patients with ACLD was 81.4%. This study demonstrates that the multivariable linear regression model and composite index can be used to diagnose patients with ACLD. The composite index and characteristic points can be clinically objective and can be used to extract effective information quickly and conveniently.

Effects of visual restoration on gait performance and kinematics of lower extremities in patients with age-related cataract.

BACKGROUND: Visual inputs are critical for locomotor navigation and sensorimotor integration in the elderly; however, the mechanism needs to be explored intensively. The present study assessed the gait pattern after cataract surgery to investigate the effects of visual restoration on locomotion. METHODS: The prospective study recruited 32 patients (70.1 ±â€Š5.2 years) with bilateral age-related cataracts in the Department of Ophthalmology at Peking University Third Hospital from October 2016 to December 2019. The temporal-spatial gait parameters and kinematic parameters were measured by the Footscan system and inertial measurement units. Paired t -test was employed to compare data normally distributed and Wilcoxon rank-sum test for non-normally distributed. RESULTS: After visual restoration, the walking speed increased by 9.3% (1.19 ±â€Š0.40 m/s vs. 1.09 ±â€Š0.34 m/s, P =0.008) and exhibited an efficient gait pattern with significant decrease in gait cycle (1.02 ±â€Š0.08 s vs. 1.04 ±â€Š0.07 s, P =0.012), stance time (0.66 ±â€Š0.06 s vs. 0.68 ±â€Š0.06 s, P =0.045), and single support time (0.36 ±â€Š0.03 s vs. 0.37 ±â€Š0.02 s, P =0.011). High amplitude of joint motion was detected in the sagittal plane in the left hip (37.6°â€Š±â€Š5.3° vs. 35.5°â€Š±â€Š6.2°, P =0.014), left thigh (38.0°â€Š±â€Š5.2° vs. 36.4°â€Š±â€Š5.8°, P =0.026), left shank (71.9°â€Š±â€Š5.7° vs. 70.1°â€Š±â€Š5.6°, P =0.031), and right knee (59.1°â€Š±â€Š4.8° vs. 56.4°â€Š±â€Š4.8°, P =0.001). The motor symmetry of thigh improved from 8.35 ±â€Š5.30% to 6.30 ±â€Š4.73% ( P =0.042). CONCLUSIONS: The accelerated gait in response to visual restoration is characterized by decreased stance time and increased range of joint motion. Training programs for improving muscle strength of lower extremities might be helpful to facilitate the adaptation to these changes in gait.

The effects of blurred visual inputs with different levels on the cerebral activity during free level walking.

Objective: The aim of this study was to evaluate the effects of blurred vision on electrocortical activities at different levels during walking. Materials and methods: A total of 22 healthy volunteers (all men; mean age: 24.4 ± 3.9 years) underwent an electroencephalography (EEG) test synchronous with free level walking. Visual status was simulated by goggles covered by the occlusion foil targeted at a Snellen visual acuity of 20/60 (V0.3), 20/200 (V0.1), and light perception (V0). At each of these conditions, the participants completed barefoot walking for five blocks of 10 m. The EEG signals were recorded by a wireless EEG system with electrodes of interest, namely, Cz, Pz, Oz, O1, and O2. The gait performances were assessed by the Vicon system. Results: During walking with normal vision (V1.0), there were cerebral activities related to visual processing, characterized as higher spectral power of delta (Oz and O2 vs. Cz, Pz, and O1, p ≤ 0.033) and theta (Oz vs. Cz and O1, p = 0.044) bands in occipital regions. Moderately blurred vision (V0.3) would attenuate the predominance of delta- and theta-band activities at Oz and O2, respectively. At the statuses of V0.1 and V0, the higher power of delta (at V0.1 and V0, Oz, and O2 vs. Cz, Pz, and O1, p ≤ 0.047) and theta bands (at V0.1, Oz vs. Cz, p = 0.010; at V0, Oz vs. Cz, Pz, and O1, p ≤ 0.016) emerged again. The cautious gait pattern, characterized by a decrease in gait speed (p < 0.001), a greater amplitude of deviation from the right ahead (p < 0.001), a prolonged stance time (p = 0.001), a restricted range of motion in the hip on the right side (p ≤ 0.010), and an increased knee flexion during stance on the left side (p = 0.014), was only detected at the status of V0. The power of the alpha band at the status of V0 was higher than that at V1.0, V0.3, and V0.1 (p ≤ 0.011). Conclusion: Mildly blurred visual inputs would elicit generalization of low-frequency band activity during walking. In circumstance to no effective visual input, locomotor navigation would rely on cerebral activity related to visual working memory. The threshold to trigger the shift might be the visual status that is as blurred as the level of Snellen visual acuity of 20/200.

Effects of peak ankle dorsiflexion angle on lower extremity biomechanics and pelvic motion during walking and jogging.

Objective: Ankle dorsiflexion during walking causes the tibia to roll forward relative to the foot to achieve body forward. Individuals with ankle dorsiflexion restriction may present altered movement patterns and cause a series of dysfunction. Therefore, the aim of this research was to clearly determine the effects of peak ankle dorsiflexion angle on lower extremity biomechanics and pelvic motion during walking and jogging. Method: This study involved 51 subjects tested for both walking and jogging. The motion capture system and force measuring platforms were used to synchronously collect kinematics and kinetics parameters during these activities. Based on the peak ankle dorsiflexion angle during walking, the 51 subjects were divided into a restricted group (RADF group, angle <10°) and an ankle dorsiflexion-unrestricted group (un-RADF group, angle >10°). Independent-Sample T-tests were performed to compare the pelvic and lower limb biomechanics parameters between the groups during walking and jogging test on this cross-sectional study. Results: The parameters that were significantly smaller in the RADF group than in the un-RADF group at the moment of peak ankle dorsiflexion in the walking test were: ankle plantar flexion moment (p < 0.05), hip extension angle (p < 0.05), internal ground reaction force (p < 0.05), anterior ground reaction force (p < 0.01), pelvic ipsilateral tilt angle (p < 0.05). In contrast, the external knee rotation angle was significantly greater in the RADF group than in the un-RADF group (p < 0.05). The parameters that were significantly smaller in the RADF group than in the un-RADF group at the moment of peak ankle dorsiflexion in the jogging test were: peak ankle dorsiflexion angle (p < 0.01); the anterior ground reaction force (p < 0.01), the angle of pelvic ipsilateral rotation (p < 0.05). Conclusion: This study shows that individuals with limited ankle dorsiflexion experience varying degrees of altered kinematics and dynamics in the pelvis, hip, knee, and foot during walking and jogging. Limited ankle dorsiflexion alters the movement pattern of the lower extremity during walking and jogging, diminishing the body's ability to propel forward, which may lead to higher injury risks.

PneuNet: deep learning for COVID-19 pneumonia diagnosis on chest X-ray image analysis using Vision Transformer.

A long-standing challenge in pneumonia diagnosis is recognizing the pathological lung texture, especially the ground-glass appearance pathological texture. One main difficulty lies in precisely extracting and recognizing the pathological features. The patients, especially those with mild symptoms, show very little difference in lung texture, neither conventional computer vision methods nor convolutional neural networks perform well on pneumonia diagnosis based on chest X-ray (CXR) images. In the meanwhile, the Coronavirus Disease 2019 (COVID-19) pandemic continues wreaking havoc around the world, where quick and accurate diagnosis backed by CXR images is in high demand. Rather than simply recognizing the patterns, extracting feature maps from the original CXR image is what we need in the classification process. Thus, we propose a Vision Transformer (VIT)-based model called PneuNet to make an accurate diagnosis backed by channel-based attention through X-ray images of the lung, where multi-head attention is applied on channel patches rather than feature patches. The techniques presented in this paper are oriented toward the medical application of deep neural networks and VIT. Extensive experiment results show that our method can reach 94.96% accuracy in the three-categories classification problem on the test set, which outperforms previous deep learning models.

Comparison of Bone Bruise Pattern Epidemiology between Anterior Cruciate Ligament Rupture and Patellar Dislocation Patients-Implications of Injury Mechanism.

Different bone bruise patterns observed using magnetic resonance imaging (MRI) after non-contact anterior cruciate ligament (ACL) rupture and lateral patellar dislocation may indicate different knee injury mechanisms. In this study, 77 ACL ruptures and 77 patellar dislocations in knee MR images taken from patients with bone bruises at our institution between August 2020 and March 2022 were selected and analyzed. In order to determine typical bone bruising patterns following by ACL rupture and patellar dislocation, sagittal- and transverse-plane images were used to determine bone bruise locations in the directions of medial-lateral and superior-inferior with MR images. The presence, intensity, and location of the bone bruises in specific areas of the femur and tibial after ACL rupture and patellar dislocation were recorded. Relative bone bruise patterns after ACL rupture and patellar dislocation were classified. The results showed that there were four kinds of bone bruise patterns (1-, 2-, 3-, and 4- bone bruises) after ACL rupture. The most common two patterns after ACL rupture were 3- bone bruises (including the lateral femoral condyle and both the lateral-medial tibial plateau, LF + BT; both the lateral-medial femoral condyle and the lateral tibial plateau, BF + LT; and the medial femoral condyle and both the medial and lateral tibial plateau, MF + BT) followed by 4- bone bruises (both the lateral-medial femoral condyle and the tibial plateau, BF + BT), 2- bone bruises (the lateral femoral condyle and tibial plateau, LF + LT; the medial femoral condyle and the lateral tibial plateau, MF + LT; the lateral femoral condyle and the medial tibial plateau, LF + MT; the medial femoral condyle and the tibial plateau, MF + MT; both the lateral-medial tibial plateau, 0 + BT), and 1- bone bruise (only the lateral tibial plateau, 0 + LT). There was only a 1- bone bruise (the latera femoral condyle and medial patella bone bruise) for patellar dislocation, and the most common pattern of patellar dislocation was in the inferior medial patella and the lateral anterior inferior femur. The results suggested that bone bruise patterns after ACL rupture and patellar dislocation are completely different. There were four kinds of bone bruise patterns after non-contact ACL rupture, while there was only one kind of bone bruise pattern after patellar dislocation in patients, which was in the inferior medial patella and lateral anterior inferior femur.

The combined treatment of entrapped Infrapatellar Branch of the Saphenous Nerve after ACL reconstruction: Ultrasound-guided perineural injection and acupotomy.

BACKGROUND: The anterior cruciate ligament (ACL) reconstruction (ACLR) under the arthroscopy is a widespread procedure for ACL rupture, which could stabilize knee and promote recovery. However, one of its complications is the injury of infrapatellar branch of saphenous nerve (IBSN). In traditional Chinese medicine, acupotomy functions via releasing and stripping adhesion tissues. Accordingly, acupotomy is suitable for the treatment of entrapped nerve injury and tissues adhesion. CASE DESCRIPTION: A 14-year-old man, who had ACLR before and returned to normal activity, presented with severe pain after a mild strain two weeks ago. The physical and imaging examinations revealed the compression injury of IBSN. METHODS: We provided the ultrasound-guided perineural injection of 0.4% lidocaine, while it only alleviates the symptoms temporally and partially. Acupotomy using a small needle knife (0.4*40 mm) was performed. RESULTS: The severe pain was immediately resolved. The visual analog pain scale (VAS) decreased from 10 to 1 and return to normal walking. The diameter of IBSN became smaller and the signal of peripheral soft tissue became hypoechoic in ultrasound. CONCLUSION: In this case, the combined treatments of ultrasound-guided perineural injection and acupotomy are thought to be innovative procedures for IBSN entrapment with relative long-lasting therapeutic effects.

Reliability and Validity of a Chinese Version of the Lysholm Score and Tegner Activity Scale for Knee Arthroplasty.

OBJECTIVE: To verify the reliability and validity of Chinese versions of the Lysholm score and the Tegner activity scale for knee arthroplasty. METHODS: Sixty-four patients undergoing total knee arthroplasty and 28 healthy volunteers were included in this study. Participants were divided into 4 groups: a pre-operation group; a 3 months post-operation group; a 1-year post-operation group; and a control group of healthy volunteers. Participants completed the Lysholm score and Tegner activity scale twice over a period of 3-7 days. RESULTS: The intraclass correlation coefficients of the Lysholm score and Tegner scale were both relatively high, at 0.99 and 0.97, respectively. Moreover, the Cronbach's alpha of the Lysholm score was 0.71. The items "locking" and "instability" differed slightly between groups (Kruskal-Wallis: for locking, χ2 (p) = 13.48, p = 0.0037; for instability, χ2 (p) = 4.32, p = 0.2292). CONCLUSION: The simplified-Chinese versions of the Lysholm score and the Tegner scale are applicable for use with patients undergoing total knee arthroplasty, and have relatively high validity and reliability. The items "locking" and "instability" should be combined with clinical data to make the Lysholm score more suitable for assessment of total knee arthroplasty.

Bilateral Alterations in Isokinetic Strength and Knee Biomechanics During Side-Cutting 1 Year After Unilateral ACL Reconstruction.

BACKGROUND: Individuals with anterior cruciate ligament (ACL) reconstruction (ACLR) are a population that has a higher risk for ACL injury compared with the general population. To reduce the reinjury rate and improve the rehabilitation outcome after ACLR, risk factors for ACL injury have to be addressed. PURPOSE: To compare the knee biomechanics during side-cutting and isokinetic strength of the thigh muscle of the reconstructed leg with those of the contralateral leg and healthy controls and investigate the knee movement asymmetries in individuals with ACLR. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 16 participants with ACLR (ACLR group; 11.8 ± 1.1 months after reconstruction) and 16 healthy controls (control group) were recruited. Landmark coordinates and ground-reaction forces during side-cutting and isokinetic strength of hamstring and quadriceps were collected. Two-way analysis of variance with the mixed design was performed to compare each dependent variable between groups and across legs. RESULTS: The reconstructed leg had a significantly smaller knee flexion angle (P = .004) and less quadriceps strength (P = .003) than the contralateral leg. The knee extension moment and knee external rotation angle were decreased compared with both the contralateral leg (P = .001, P = .003, respectively) and the healthy control leg (P = .001, P = .001, respectively). The ACLR group showed greater knee abduction angles (P = .004) and smaller knee external rotation moments (P = .006) than the control group. The ACLR group also demonstrated greater asymmetries of knee flexion angle (P = .015), knee external rotation angle (P = .001), knee extension moment (P = .013), knee abduction moment (P = .001), and quadriceps strength (P = .046) than the control group. CONCLUSION: Knee biomechanics in the leg with ACLR were altered mainly in the sagittal plane during side-cutting compared with the contralateral leg. The altered movement patterns between the ACLR and control groups were primarily observed in the frontal and transverse planes. The ACLR group also demonstrated greater asymmetries of sagittal knee movement and concentric quadriceps strength than the control group. CLINICAL RELEVANCE: Individuals with ACLR showed different alterations in the reconstructed and contralateral leg compared with healthy controls. These results suggest that rehabilitation programs after ACLR should further focus on restoring the knee flexion angle and quadriceps strength. Injury prevention programs need to be further targeted in the altered movement patterns observed between the ACLR and the healthy groups.

Finite Element Analysis and Experimental Validation of the Anterior Cruciate Ligament and Implications for the Injury Mechanism.

This study aimed to establish a finite element model that vividly reflected the anterior cruciate ligament (ACL) geometry and investigated the ACL stress distribution under different loading conditions. The ACL's three-dimensional finite element model was based on a human cadaveric knee. Simulations of three loading conditions (134 N anterior tibial load, 5 Nm external tibial torque, 5 Nm internal tibial torque) on the knee model were performed. Experiments were performed on a knee specimen using a robotic universal force/moment sensor testing system to validate the model. The simulation results of the established model were in good agreement with the experimental results. Under the anterior tibial load, the highest maximal principal stresses (14.884 MPa) were localized at the femoral insertion of the ACL. Under the external and internal tibial torque, the highest maximal principal stresses (0.815 MPa and 0.933 MPa, respectively) were mainly concentrated in the mid-substance of the ACL and near the tibial insertion site, respectively. Combining the location of maximum stress and the location of common clinical ACL rupture, the most dangerous load during ACL injury may be the anterior tibial load. ACL injuries were more frequently loaded by external tibial than internal tibial torque.

The effectiveness and sustainability of supervised balance training in chronic ankle instability with grade III ligament injury: a one-year prospective study.

BACKGROUND: To determine the effectiveness and sustainability of supervised balance training in people with chronic ankle instability (CAI) with grade III ligament injury. METHODS: Twenty young adults (12 males and 8 females) diagnosed with CAI with grade III ligament injury underwent 3 months of supervised balance training. The self-reported functional questionnaire, plantar pressure (walking and single leg standing), and isokinetic ankle strength were consecutively evaluated at pre-training, 3 months, 6 months and one year. Paired T tests were used to explore changes in muscle strength and plantar pressures following the supervised balance training. According to whether the patient had sprain recurrence, the patients were divided into sprain recurrence group and control group. The risk factors of sprain recurrence were explored with univariate analysis and multivariable logistic regression. RESULTS: The self-reported functional scores, the plantar pressure distribution and the muscle strength showed significant immediate improvements after 3 months of supervised balance training. At 6 months post-training, peak force under 2nd metatarsal, time to peak force under the medial hindfoot, time to boundary measurements and dorsiflexion, and eversion strength were partly declined to the pre-training level. 16 patients (80%) resumed the daily life and sports without sprain recurrence during the follow-up. Four patients (20%) reported ankle sprain during the follow-up, and the sprain recurrence group showed significantly higher Beighton scores (p = 0.012) and weaker initial inversion strength (p = 0.022) than the control group. CONCLUSIONS: Three months' of supervised balance training could effectively improve postural control and muscle strength of CAI cases with grade III ligament injury, although these improvements would partially deceased over time. Additional strength exercises for dorsiflexion and eversion should be supplemented from 6 months. Higher Beighton score and initial inversion muscle strength weakness might increase the risk of sprain recurrence. TRIAL REGISTRATION: ChiCTR, ChiCTR1900023999, Registered 21 June 2019, https://www.chictr.org.cn/edit.aspx?pid=39984&htm=4.

Identification of Kinetic Abnormalities in Male Patients after Anterior Cruciate Ligament Deficiency Combined with Meniscal Injury: A Musculoskeletal Model Study of Lower Limbs during Jogging.

There is little known about kinetic changes in anterior cruciate ligament deficiency (ACLD) combined with meniscal tears during jogging. Therefore, 29 male patients with injured ACLs and 15 healthy male volunteers were recruited for this study to investigate kinetic abnormalities in male patients after ACL deficiency combined with a meniscal injury during jogging. Based on experimental data measured by an optical tracking system, a subject-specific musculoskeletal model was employed to estimate the tibiofemoral joint kinetics during jogging. Between-limb and interpatient differences were compared by the analysis of variance. The results showed that decreased knee joint forces and moments of both legs in ACLD patients were detected during the stance phase compared to the control group. Meanwhile, compared with ACLD knees, significantly fewer contact forces and flexion moments in ACLD combined with lateral and medial meniscal injury groups were found at the mid-stance, and ACLD with medial meniscal injury group showed a lower axial moment in the loading response (p < 0.05). In conclusion, ACLD knees exhibit reduced tibiofemoral joint forces and moments during jogging when compared with control knees. A combination of meniscus injuries in the ACLD-affected side exhibited abnormal kinetic alterations at the loading response and mid-stance phase.

The effect of cognitive loading on the lower extremity movement coordination variability in patients with anterior cruciate ligament reconstruction.

BACKGROUND: The altered coordination variability was related to anterior cruciate ligament (ACL) re-injury after ACL reconstruction (ACL-R). As motor performance is affected by the cognitive loading, understanding the interaction of cognition and coordination variability is crucial for addressing secondary injury prevention and restoring function in rehabilitation programs. RESEARCH QUESTION: To investigate the lower extremity movement coordination variability asymmetry in individuals following ACL-R and determine the effects of cognitive loading on the coordination variability. METHODS: Twenty-five males who received unilateral ACL-R using hamstring tendon autograft (7.4 ± 1.3 months past reconstruction). Participants performed walking without (single-task condition) and with the concurrent cognitive task (dual-task condition). The coordination variability in hip-knee coupled motion in different gait phases was calculated using vector coding technique. RESULTS: The injured leg demonstrated greater coordination variability in hip flexion/knee flexion (HF/KF) during mid-stance phase (P = 0.012) than the uninjured leg in both conditions. No significant differences were observed in other phases of HF/KF variability or other measures in all phases between the injured and uninjured legs. Both legs increased the HF/KF coordination variability during loading response phase in dual-task condition than that in single-task condition (P < 0.001). SIGNIFICANCE: Individuals following ACL-R demonstrated coordination variability asymmetry of sagittal plane hip-knee coupled motion. The dual cognitive task increased the coordination variability of hip flexion/knee flexion during loading response phase in individuals following ACL-R.

Response to the Letter to the Editor on "Prediction of Knee Kinematics at Time of Noncontact Anterior Cruciate Ligament Injuries Based on Bone Bruises".

The present Letter responded to the Letter to the Editor on "Prediction of Knee Kinematics at Time of Noncontact Anterior Cruciate Ligament Injuries Based on Bone Bruises" from Grassi et al.

Prediction of Knee Kinematics at the Time of Noncontact Anterior Cruciate Ligament Injuries Based on the Bone Bruises.

Biomechanical risk factors associated with the alignment and position of the knee for anterior cruciate ligament (ACL) injury are still not conclusive. As bone bruises identified on magnetic resonance imaging (MRI) following acute ACL injury could represent the impact footprint at the time of injury. To improve understanding of the ACL injury mechanism, we aimed to determine the knee kinematics during ACL injury based on the bone bruises. Knee MRI scans of patients who underwent acute noncontact ACL injuries were acquired. Numerical optimization was used to match the bone bruises of the femur and tibia and predict the knee positions during injury. Knee angles were compared between MRI measured position and predicted position. The knee flexion, abduction, and external tibial rotation angles were significantly greater in the predicted position than that in MRI measured position. Relative to MRI measured position, patients had a mean of 34.3 mm of anterior tibial translation, 4.0 mm of lateral tibial translation, and 16.0 mm superior tibial translation in the predicted position. The results suggest that knee valgus and external tibial rotation accompanied by knee flexion are high-risk movement pattern for ACL injury in patients with lateral compartment bone bruising in conjunction with ACL injury.

Comparison Between Soccer and Basketball of Bone Bruise and Meniscal Injury Patterns in Anterior Cruciate Ligament Injuries.

BACKGROUND: The varying effectiveness of anterior cruciate ligament (ACL) injury prevention programs between soccer and basketball may be due to differences in sport-specific injury mechanisms. Bone bruise patterns may provide information regarding injury mechanisms. PURPOSE: To compare bone bruise and meniscal injury patterns for ACL injuries sustained in soccer versus basketball. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Clinical notes, operative reports, and magnetic resonance imaging scans were reviewed for patients who sustained a noncontact ACL rupture while playing soccer or basketball between August 2016 and August 2018. The presence, location, and signal intensity of bone bruises on the tibia and femur were documented, and patterns were classified according to the location of the bone bruise in the lateral-medial direction. The meniscal and bone bruise injury patterns and the specific bone bruise locations were compared between the soccer and basketball groups. RESULTS: Overall, 138 patients were included (56 with soccer-related and 82 with basketball-related ACL injury). No significant difference between the groups was observed in bone bruise patterns (P = .743) or meniscal injury patterns (P = .952). Bone bruise on the lateral side only of both the femur and the tibia was the most common pattern in both soccer (41.9%) and basketball (47.0%) groups; the most common meniscal injury type was an isolated lateral meniscal injury in both soccer (50.0%) and basketball (45.0%) groups. For patients with bone bruises on both the lateral and the medial sides of both the femur and the tibia (BF+BT), the bone bruise signal intensity on the lateral side of the femur (P < .001) and tibia (P = .009) was significantly higher than that on the medial side for both groups. The bone bruises on the lateral side of the femur (P < .001) and tibia (P = .002) were significantly more anterior than those on the medial side for patients with the BF+BT pattern. CONCLUSION: No significant differences in bone bruise location or meniscal injury type were detected when comparing ACL injuries sustained during soccer versus basketball. The study results suggest a similar biomechanical loading pattern for ACL injuries in these sports.