ABSTRACT
Objective:To observe the effect of taping on the kinematic characteristics of the ankle joint during forward and lateral jumps by male basketball players with chronic ankle instability (CAI).Methods:A Vicon 3D motion capture system and a Kistler 3D ergometer were used to collect data describing the landing data with or without taping from forward and lateral jumps of 29 male basketball players with CAI. The landing data included the dorsiflexion and plantarflexion angles, valgus and inversion angles and external and internal rotation angles. Dorsiflexion or plantarflexion angular velocity was also recorded along with valgus or inversion angular velocity and external or internal rotation angular velocity 200ms, 150ms, 100ms and 50ms before and after touchdown. The data obtained were modeled using three-dimensional motion analysis software, and then analyzed.Results:Taping reduced the ankle plantarflexion in landing from a forward jump by 3.27° 50ms before landing and by 2.70° at touchdown. The ankle inversion angle was reduced 2.13° 50ms before touchdown, while the angle of external rotation decreased by 2.59° 200ms before touchdown and 2.17° 150ms before. Moreover, the angle of external rotation 100ms after landing was reduced by a significant 1.59° compared with that without taping. In lateral jumps taping reduced the average ankle plantarflexion angle by 1.94° 50ms before landing and 3.23° at touchdown compared with no taping. Ankle inversion was reduced significantly by 2.86° 50ms before landing and by 2.87° at touchdown. External rotation was a significant 0.93° less 200ms before landing and 2.36° smaller 150ms before touchdown. In the forward jump landing, taping reduced the average angular velocity of ankle dorsiflexion on landing by a significant 58.5°/s and by 28.39°/s 100ms later. In the lateral jump landings the average ankle dorsiflexion velocity decreased by significant 20.5°/s with taping, but the valgus velocity increased by 49.7°/s compared with no taping. However, 50ms after touchdown the speed of external rotation with taping was 30.3°/s slower than without taping.Conclusions:Ankle taping can modify ankle rotation angles and angular velocities during landing from jumps. This is particularly helpful for basketball players with CAI.
ABSTRACT
Objective:To investigate the efficacy of the biopsy strategy combining 6-core systematic and 3-core MRI-targeted biopsy on prostate cancer (PCa) detection in biopsy-na?ve patients.Methods:The clinical data of 121 biopsy-na?ve patients who underwent transperineal prostate biopsy in West China Hospital of Sichuan University from July 2018 to January 2020 were retrospectively analyzed. The average age was (64.7±9.1) years old. Pre-biopsy prostate-specific antigen (PSA) was (12.4±7.5)ng/ml, f/t PSA was 0.13±0.05. Prostate volume was (43.1±26.1) ml and PASD was (0.35±0.27) ng/ml 2. The prostate-imaging and data system (PI-RADS) score of MRI before biopsy was reported to be 3 for 29 patients (24.0%), 4 for 54 patients (44.6%) and 5 for 38 patients (31.8%). All 121 patients underwent 12-core systematic biopsy combined with a 3-core or 5-core MRI-targeted biopsy, of which 61 patients underwent 3-core targeted biopsy and 60 underwent 5-core targeted biopsy. There was no significant difference in the pre-biopsy clinical data between the two groups ( P>0.05). A 6-core systematic biopsy was redefined as the results of 6 cores among the 12-core systematic biopsy. We compared the detection rates among the single 12-core systematic biopsy, 6-core systematic biopsy, MRI-targeted biopsy (3-core or 5-core), and different systematic biopsy combing with targeted biopsy for any PCa and clinically significant PCa, and we also analyzed the cumulative cancer detection rates for MRI-targeted biopsy of different cores. Results:Of the 121 patients in this study, the biopsy results were negative for 43 patients (35.5%) and positive for 78 (64.5%). The detection rate of clinically significant PCa was 55.4% (67/121). The detection rate of the 6-core systematic biopsy combined with MRI-targeted biopsy was 62.0% (75/121) for PCa and 55.4% (67/121) for clinically significant PCa, which was of no difference compared with that for the 12-core systematic biopsy combined with MRI-targeted biopsy ( P>0.05), but the 6-core systematic biopsy combined with MRI-targeted biopsy avoided the overdiagnosis of 3 patients with Gleason score 3+ 3. The detection rate of PCa for MRI-targeted biopsy was 57.9% (70/121), including 42.1% (51/121) for the first core, 55.4% (67/121) for the first two cores, and 57.9% (70/121) for the first three cores. Compared with the single-core targeted biopsy for suspicious lesions, the first 2-core targeted biopsy ( OR=1.7, 95% CI 1.0-2.8) and 3-core targeted biopsy ( OR=1.9, 95% CI 1.1-3.1) can significantly increase the detection rate of PCa, while the fourth or fifth core of targeted biopsy can not increase the detection rate additionally (60%, 36/60). Conclusion:For patients with suspected PCa, the prostate biopsy strategy combing 6-core systematic and 3-core MRI-targeted biopsy performs no inferior than the current 12-core systematic biopsy combined with MRI-targeted biopsy.
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Objective To investigate the characteristics of knee kinematics and ground reaction force (GRF), as well as the stress state of cartilage and meniscus in the process of lateral incisions at different cutting angles under expected conditions. Methods Kinematics and GRF data of 14 subjects at 45°, 90° and 135° cutting angle respectively under expected conditions were collected. The knee joint reaction force was obtained through the inverse dynamics calculation of Visual 3D. Based on three-dimensional (3D) finite element model of the knee joint, the contact process at 3 lateral cutting angles was simulated. ResultsUnder expected conditions, there were significant differences in knee joint kinematics characteristics at 3 cutting angles during contact process(P＜0.001), and the knee flexion increased with the cutting angle increasing; the vertical GRF decreased significantly with the cutting angle increasing (P＜0.001), while the horizontal GRF showed the opposite trend; for 3 cutting angles, the peak contact stress of patellar cartilage and femoral cartilage was larger at 90° cutting angle, the peak principal stress at anterior cruciate ligament (ACL) contact point was also larger at 90° cutting angle, and the following was at 135° and 45° cutting angle, respectively; the peak contact stress of lateral femoral cartilage was larger than that of medial femoral cartilage at 3 cutting angles. Conclusions The risk of knee joint injury is higher at 90° cutting angle, and the stress state of knee joint at 135° cutting angles is better than that at 90° cutting angle, and the risk of knee joint injury does not increase with the increase of cutting angle under expected conditions.
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Objective To discuss rationality of the three-link model used in analysis on interactive dynamics of deep squatting, and clarify the source of differences in calculation of joint torque by three-link model and Visual 3D. Methods Eight subjects were selected to obtain kinematic data of the squat motion through Vicon. The second Lagrangian equation was used to establish the three-link dynamic equation. The joint torque was calculated based on the Mathematica programming. The results were compared with the calculation results of lower limb chain segment model by Visual 3D, and the similarity between the two results was evaluated by the coefficient of complex correlation (CMC). Results The CMC of hip joint and knee joint from 8 subjects was larger than 0.85, and the CMC of ankle joint was between 0.50-0.85. The joint torque calculated by three-link dynamic equation and Visual 3D was highly similar in hip joint and knee joint, and there was only a moderate similarity in ankle joint. Conclusions The three-link model can be used in further analysis on interactive dynamics of deep squatting, but the influence of interactive moment caused by ground reaction force (external moment) on ankle torque should be considered.