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Traditional motion analysis systems are impractical for widespread screening of non-contact anterior cruciate ligament (ACL) injury risk. The Kinect V2 has been identified as a portable and reliable alternative but was replaced by the Azure Kinect. We hypothesize that the Azure Kinect will assess drop vertical jump (DVJ) parameters associated with ACL injury risk with similar accuracy to its predecessor, the Kinect V2. Sixty-nine participants performed DVJs while being recorded by both the Azure Kinect and the Kinect V2 simultaneously. Our software analyzed the data to identify initial coronal, peak coronal, and peak sagittal knee angles. Agreement between the two systems was evaluated using the intraclass correlation coefficient (ICC). There was poor agreement between the Azure Kinect and the Kinect V2 for initial and peak coronal angles (ICC values ranging from 0.135 to 0.446), and moderate agreement for peak sagittal angles (ICC = 0.608, 0.655 for left and right knees, respectively). At this point in time, the Azure Kinect system is not a reliable successor to the Kinect V2 system for assessment of initial coronal, peak coronal, and peak sagittal angles during a DVJ, despite demonstrating superior tracking of continuous knee angles. Alternative motion analysis systems should be explored. [ABSTRACT FROM AUTHOR]

Knee kinematics during a drop vertical jump, measured by the Kinect V2 (Microsoft, Redmond, WA, USA), have been shown to be associated with an increased risk of non-contact anterior cruciate ligament injury. The accuracy and reliability of the Microsoft Kinect V2 has yet to be assessed specifically for tracking the coronal and sagittal knee angles of the drop vertical jump. Eleven participants performed three drop vertical jumps that were recorded using both the Kinect V2 and a gold standard motion analysis system (Vicon, Los Angeles, CA, USA). The initial coronal, peak coronal, and peak sagittal angles of the left and right knees were measured by both systems simultaneously. Analysis of the data obtained by the Kinect V2 was performed by our software. The differences in the mean knee angles measured by the Kinect V2 and the Vicon system were non-significant for all parameters except for the peak sagittal angle of the right leg with a difference of 7.74 degrees and a p-value of 0.008. There was excellent agreement between the Kinect V2 and the Vicon system, with intraclass correlation coefficients consistently over 0.75 for all knee angles measured. Visual analysis revealed a moderate frame-to-frame variability for coronal angles measured by the Kinect V2. The Kinect V2 can be used to capture knee coronal and sagittal angles with sufficient accuracy during a drop vertical jump, suggesting that a Kinect-based portable motion analysis system is suitable to screen individuals for the risk of non-contact anterior cruciate ligament injury. [ABSTRACT FROM AUTHOR]

Currently, in patients with malignant melanoma there is no clear cut-off point of Breslow thickness in order to avoid unnecessary lymph node excision surgery, without missing metastatic nodes. We retrospectively studied a cohort of 64 patients, with pathologically proven malignant melanoma, who underwent lymph node scintigraphy and surgical resection of the sentinel node, during the last two years. The patients were divided into 5 groups: Group 1: Ten patients, mean age 46 ± 6 years (range 40-55 years), with Breslow thickness of the lesion 0.51-0.75 mm. Group 2: Eleven patients, mean age 41 ± 9 years (range 31-61 years), with Breslow thickness 0.76-1mm. Group 3: Twelve patients, mean age 59 ± 12 (41-76 years), with Breslow thickness 1.01-1.25 mm. Group 4: Fourteen patients, mean age 61 ± 8 (38-74 years), with Breslow thickness 1.26-1.5mm. Group 5: Seventeen patients, mean age 56 ± 10 (32-71 years), with Breslow thickness >1.5mm. We found only seven infiltrated sentinel lymph nodes. From these, 3 patients belonged to the 5th group (Breslow>1.5mm), two patients to the 4th group (Breslow 1.26-1.5mm), one patient in the 3rd group (Breslow 1.01-1.25 mm) and one patient to the 2nd group (Breslow 0.76-1mm). Since there was no positive sentinel lymph node in any patient with Breslow thickness less than < 0.75 mm, we conclude that sentinel lymph node biopsy in patients with Breslow thickness less than < 0.75 mm may not be useful and might not be carried out, except in high risk cases such as melanomas with ulceration, high mitotic rate and vertical growth phase.