Measurement of Knee Rotation Angles Using a Smartphone Application: An Experimental Study of Porcine Knees.

PURPOSE: This study evaluated the efficacy of a smartphone application in the measurement of rotation angles in porcine knees. MATERIALS AND METHODS: Two K-wires were fixated to the femoral condyle and anterior tibial crest of 10 porcine legs. The angle created between the K-wires with an external rotation force applied was measured on a photograph and defined as the true angle. The same force was applied to the legs placed on a splint with a smartphone attached to the plantar side. The angle presented on a smartphone application was determined as the measured angle. The differences between the true and measured angles in 30° and 90° knee flexion and differences in measured angles depending on the status of the popliteus tendon were compared. RESULTS: In the intact knees, the mean true angles in 30° and 90° flexion were 20.5°±1.4° and 19.1°±1.3°, respectively, and the mean measured angles in 30° and 90° flexion were 21.1°±0.9° and 18.6°±1.6°, respectively. When the popliteus tendon was cut, the mean true angles in 30° and 90° flexion were 31.4°±1.1° and 38.5°±2.5°, respectively, and the mean measured angles in 30° and 90° flexion were 31.8°±1.2° and 39.2°±2.8°, respectively. The differences between the true and measured angles were not significant. The measured angle increased by more than 10° after cutting of the popliteus tendon in both 30° and 90° flexion. CONCLUSIONS: Using a smartphone application could be a good method of measuring knee rotation.

Radiological analysis of minimal safe distance and optimal screw angle to avoid facet violation in open-door laminoplasty using precontoured plate.

PURPOSE: This study aimed to present radiologic analysis of minimal safe distance (MSD) and optimal screw angle (OSA) that enables to fix screws in a lateral mass safely without facet joint violation in open-door laminoplasty using a plate. METHODS: A retrospective analysis was made of 22 patients (male: 17; female: 5), average age 62 years. Seventy-nine lateral mass screws were fixed among a total of 158 screws. MSD that doesn't allow 5-mm screws to violate a facet joint was measured for C3-C7 and a comparative analysis was performed. If the MSD is not secured, the OSA to be given to the cephalad direction is calculated to avoid violation of the facet joint. RESULTS: The screws violating inferior facet joints accounted for 34.1% of the screws fixed in inferior lateral mass. Joint surface to distal mini-screw distances were 3.18 ± 1.46 mm and 4.75 ± 1.71 mm in groups of facet joint violation and non-facet violation (FV), respectively ( p = 0.001). When 5-mm screws were inserted into a lateral mass, MSD was 4.39 ± 0.83 mm. The average MSD of C3, C4, and C5 was 4.05 ± 0.78 mm, 4.10 ± 0.70 mm, and 4.26 ± 0.74 mm, respectively. There was no significant differences among levels ( p > 0.05). The average MSD of C6 and C7 was 4.92 ± 0.81 mm and 4.80 ± 0.96 mm, respectively, showing significant differences from those of C3, C4, and C5 ( p < 0.05). If 6 mm of the MSD isn't secured, OSA showed in the cephalad direction of 11.5° for 5 mm and 22° for 4 mm approximately. CONCLUSION: We suggest that mini-screw on lateral mass can be fixed safely without FV, if they are fixed at MSD of 6 mm from a joint surface. Facet joint violation doesn't occur if an OSA is given in the cephalad direction in case of not enough MSD for mini-screws.

Neutrophil extracellular traps (NETs) in autoimmune diseases: A comprehensive review.

Neutrophil extracellular traps (NETs) are fibrous networks which protrude from the membranes of activated neutrophils. NETs are found in a variety of conditions such as infection, malignancy, atherosclerosis, and autoimmune diseases including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV), psoriasis, and gout. Studies suggest that an imbalance between "NETosis," which is a process by which NETs are formed, and NET degradation may be associated with autoimmune diseases. Neutrophils, interleukin-8, ANCA and other inflammatory molecules are considered to play a key role in NET formation. Prolonged exposure to NETs-related cascades is associated with autoimmunity and increases the chance of systemic organ damage. In this review, we discuss the roles of various inflammatory molecules in relation to NETs. We also describe the role of NETs in the pathogenesis of autoimmune diseases and discuss the possibility of using targeted therapies directed to NETs and associated molecules to treat autoimmune diseases.

Angular deformity correction by guided growth in growing children: Eight-plate versus 3.5-mm reconstruction plate.

BACKGROUND: Guided growth using the eight-plate (8-plate) is the most commonly used method to correct angular deformities in children; however, implant failure has been reported. Recently, the 3.5-mm reconstruction plate (R-plate) has been used as an alternative option for guided growth; however, hardware prominence has been problematic. This study aimed to compare the coronal angular deformity correction results of guided growth between relatively thin 8-plates with cannulated screws and thick R-plates with solid screws. METHODS: Thirty-nine physes (24 distal femoral, 15 proximal tibial) in 20 patients underwent hemiepiphysiodesis using 8-plates, and 61 physes (40 distal femoral, 21 proximal tibial) in 35 patients underwent hemiepiphysiodesis using R-plates. Coronal angular corrections were measured and compared preoperatively, and after the completion of corrections. Amounts and rates of correction and complications were compared between the groups. RESULTS: Mean body mass index was 18.7 kg/m2 in the 8-plate group, and 22.7 kg/m2 in the R-plate group. Angular correction was achieved in all deformities at a mean of 13.7 months and 19.7 months in the 8-plate and the R-plate group, respectively. The mean corrected mechanical lateral distal femoral angle was 9.0° in the 8-plate group, and 9.9° in the R-plate group (P = 0.55). The mean corrected medial proximal tibial angle was 7.1° in the 8-plate group, and 9.0° in the R-plate group (P = 0.07). The mean rates of angular correction were also not significantly different in the distal femur (1.03°/month vs. 0.77°/month, P = 0.2) and the proximal tibia (0.66°/month vs. 0.63°/month, P = 0.77). There was one superficial infection in each group, and one case of implant failure in the R-plate group. Two rebound deformities were observed and needed repeat hemiepiphysiodesis. Permanent physeal arrest was not observed in this series.