Study Design. Retrospective magnetic resonance imaging grading with comparison between experts and deep convolutional neural networks (CNNs). Objective. This study aims to verify the feasibility of a computer-assisted spine stenosis grading system by comparing the diagnostic agreement between two experts and the agreement between the experts and trained artificial CNN classifiers. Summary of Background Data. Spinal stenosis grading is important; however, it is tedious job to check the MR images slide by slide to classify patient grades often having different opinions regarding the final diagnosis. Methods. For 542 L4-5 axial MR images, two experts independently localized the center position of the spine canal and graded the status. Two CNN classifiers each trained with the grading label made by the two experts were validated using 10-fold cross-validation. Each classifier consisted of a CNN detection model responsible for the localization of patches near the canal and a classification CNN model to predict the spinal stenosis status in the localized patches. Faster R-CNN was used for the detection model whereas VGG network was used for the classification model. A comparison in grading agreement was carried out between the two experts as well as that of the experts and the prediction results generated by the CNN models. Results. Grading agreement between the experts was 77.5% and 75% in terms of accuracy and F1 scores. The agreement between the first expert and the model trained with the labels of the first expert was 83% and 75.4%, respectively. The agreement between the second expert and the model trained with the labels of the second expert was 77.9% and 74.9%. The differences between the two experts were significant, whereas the differences between each expert and the trained models were not significant. Conclusion. We indeed confirmed that automatic diagnosis using deep learning may be feasible for spinal stenosis grading. Level of Evidence: 4

PurposeTo evaluate the hemostatic effect of intraarticular injection of a thrombin-based hemostatic agent in total knee arthroplasty (TKA).Materials and MethodsWe performed a prospective randomized controlled trial on the use of a thrombin-based hemostatic agent in patients undergoing unilateral TKA. A total of 100 TKA patients were enrolled, with 50 patients randomized into the study group and the other 50 patients into the controlled group. Drain output, hemoglobin level, total red blood cell loss for 24 hours after surgery, transfusion rates, and complications were assessed.ResultsPostoperative drain output was 525 mL in the study group and 667 mL in the control group (p=0.01). Nine patients in the study group and eighteen in the control group received blood transfusion (p=0.043). But, there was no significant difference between two groups in terms of hemoglobin level change and total red blood cell loss (p>0.05).ConclusionsThe thrombin-based hemostatic agent demonstrated efficacy in reducing drain output and blood transfusion rates. Thus, we believe the use of a thrombin-based hemostatic agent should be considered as an option in orthopedic surgery that involves massive bleeding.

Background The topographic arrangement of sensory receptors in the human elbow joint capsule is pertinent to their role in the transmission of neural signals. The signals from stimuli in the joint are concisely delivered via afferent pathways to allow recognition of pain and proprioception. Sensory receptors in the elbow joint include mechanoreceptors and free nerve endings acting as nociceptors, although the distribution of each of the structures has not been determined, despite their importance for the integrity of the joint. We therefore aimed to investigate the neuroanatomical distribution and densities of mechanoreceptors and free nerve endings in the capsule of the elbow, at the same time as considering surgical approaches that would result in the minimum insult to them. Methods Four elbow joint capsules were harvested from fresh cadavers. The specimens were carefully separated from adjacent osteoligamentous attachments and the capsular complex was stained with a modified gold chloride method. Evaluations of free nerve endings, and Golgi, Ruffini and Pacinian corpuscles were performed under an inverted light microscope. The number and density of each structure were recorded. Results Ruffini corpuscles observed to be the dominant mechanoreceptor type. No Golgi corpuscle was observed. Free nerve endings were found at the highest density at posterodistal sites, whereas mechanoreceptors were most frequent at bony attachment sites. Conclusions A consistent distribution pattern of articular sensory receptors was observed, which allows further understanding of elbow pathology. An awareness of the neuroanatomical distribution of sensory receptors in the elbow joint capsule may allow their preservation during surgical procedures for elbow joint pathology.

No abstract

BackgroundSuspension ligamentoplasty using abductor pollicis longus (APL) tendon without bone tunneling, was introduced as one of the techniques for treatment of advanced first carpometacarpal (CMC) arthritis. The purpose of this study was to evaluate the radiologic and clinical results of APL suspension ligamentoplasty.MethodsThe medical records of 19 patients who underwent APL suspension ligamentoplasty for advanced first CMC arthritis between January 2008 and May 2012 were reviewed retrospectively. The study included 13 female and 6 male patients, whose mean age was 62 years (range, 43 to 82 years). For clinical evaluation, we assessed the grip and pinch power, radial and volar abduction angle, thumb adduction (modified Kapandji index), including visual analogue scale (VAS) and Disabilities of the Arm, Shoulder and Hand (DASH) scores. Radiologic evaluation was performed using simple radiographs.ResultsThe mean follow-up was 36 months (range, 19 to 73.7 months). Mean power improved from 18.3 to 27 kg for grip power, from 2.8 to 3.5 kg for tip pinch, and from 4.3 to 5.4 kg for power pinch. All patients showed decreased VAS from 7.2 to 1.7. Radial abduction improved from 71° preoperatively to 82° postoperatively. The modified Kapandji index showed improvement from 6 to 7.3, and mean DASH was improved from 41 to 17.8. The height of the space decreased from 10.8 to 7.1 mm. Only one case had a complication involving temporary sensory loss of the first dorsal web space, which resolved spontaneously.ConclusionsThe APL suspension ligamentoplasty for treatment of advanced first CMC arthritis yielded satisfactory functional results.