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Objectives With the advent of new optical technologies, early pharyngolaryngeal cancerous lesions can be better visualized. Although the conventional transnasal approach offers great views of the hypopharynx and larynx, the visualization of the oropharynx and palatine tonsils is limited. Through the transoral insertion of a flexible video-laryngoscope, direct views of the oropharynx and oral cavity can be obtained. Thus, transoral examination may contribute to primary detection of cancers of unknown primary (CUP). Methods Eighty-five CUP patients from Tokai University were included retrospectively in this study, from 2006 to 2017. Starting in 2010, we employed the transoral examination in addition to our conventional method. The primary detection rates were compared before and after 2010. Oropharyngeal primaries were further analyzed for tumor subsite and p16 status. Results The overall primary detection rate did not improve with the addition of transoral examination. However, greater numbers of oropharyngeal primaries were detected. The oropharyngeal lesions detected by transoral examination were mainly p16 positive, located on the palatine tonsil. Conclusion Transoral examination is a noninvasive, easy method to adopt in an outpatient setting, and a promising technique to improve tumor detection in this era of human papillomavirus-associated head and neck cancers. Level of evidence 3.

A growing number of spinal cord injury, neuromodulation, and cell therapy studies on porcine models, especially the Yucatan minipigs (YMPs), have been recently reported. This is due to the large similarities between human and porcine neuroanatomy and biomechanics. To assess treatment modalities and locomotor recovery in this model, there is an obvious need for detailed characterization of normative overground gait in neurologically intact YMPs. The objective of this study was to assess gait biomechanics and the effect of overground walking speed on gait parameters, kinematics, and electromyographic (EMG) activity in the hindlimb muscles of YMPs. Nine neurologically-intact adult YMPs were trained to walk overground in a straight line. Whole-body kinematics and EMG activity of hindlimb muscles were recorded and analyzed at 6 different speed ranges (0.4-0.59, 0.6-0.79, 0.8-0.99, 1.0-1.19, 1.2-1.39, and 1.4-1.6 m/s). A MATLAB program was developed to detect strides and gait events automatically from motion-captured data. Significant decreases in stride duration, stance and swing times and an increase in stride length were observed with increasing speed. A transition in gait pattern occurred at the 1.0m/s walking speed. Significant increases in the range of motion of the knee and ankle joints were observed at higher speeds. Also, the points of minimum and maximum knee and ankle joint angles occurred earlier in the gait cycle at higher speeds. The onset of EMG activity in the biceps femoris muscle occurred significantly earlier in the gait cycle with increasing speed. A comprehensive characterization of overground walking in neurologically-intact YMPs is provided. These normative measures set the basis against which the effects of future interventions on locomotor capacity in YMPs can be compared.

Background/Purpose: Studies investigating the trends of anterior cruciate ligament (ACL) reconstruction rates have shown that since 2006, females aged 13 - 17 years of age have had the highest injury rates of any age or gender group in the country. This study investigated the lower chain biomechanics of landing before and after a six-session training intervention. This training ses-sion was conducted between the fall and spring season break for a travel soccer club. Study design: Non-randomized controlled follow-up study. Methods: Thirty-six healthy, female soccer players between the ages of ten and fifteen years old participated. Using an inertial tracking system for three-dimensional kinematic (motion) analyses of a drop jump assessment that were conducted before and after a six-session training intervention focused on proximal hip strengthening, motor control, and lower extremity loading strategies. The study took place over a period of eight weeks. Results: When compared to pre-intervention measures for the drop jump, post-intervention measures were significantly improved bilaterally for each of the following variables: knee flexion (p = 0.000), hip flexion (p = 0.000), and hip abduction (p = 0.002. As compared to pre-test jump height, post-test jump heights were significantly lower by an average value of 1.8034 cm (p = 0.005). Conclusions: The results of this study showed that a short duration (six, 90 min, sessions occurring over 8 weeks) training intervention can significantly influence the landing kinematics in adolescent female soccer players during a drop jump assessment. Increased peak values of hip and knee flexion along with decreased hip adduction during landing indicate a more optimal loading technique associated with decreased risk of ACL injury. The inertial motion analysis system was a useful screening tool for identifying high-risk biomechanics that must be addressed to develop successful ACL injury prevention programs.

OBJECTIVEThe overall goal of this study was to develop an image-guided spinal stereotactic setup for intraoperative intraspinal microstimulation (ISMS). System requirements were as follows: 1) ability to place implants in various segments of the spinal cord, targeting the gray matter with a < 0.5-mm error; 2) modularity; and 3) compatibility with standard surgical tools.METHODSA spine-mounted stereotactic system was developed, optimized, and tested in pigs. The system consists of a platform supporting a micromanipulator with 6 degrees of freedom. It is modular and flexible in design and can be applied to various regions of the spine. An intraoperative ultrasound imaging technique was also developed and assessed for guidance of electrode alignment prior to and after electrode insertion into the spinal cord. Performance of the ultrasound-guided stereotactic system was assessed both in pigs (1 live and 6 fresh cadaveric pigs) and on the bench using four gelatin-based surrogate spinal cords. Pig experiments were conducted to evaluate the performance of ultrasound imaging in aligning the electrode trajectory using three techniques and under two conditions. Benchtop experiments were performed to assess the performance of ultrasound-guided targeting more directly. These experiments were used to quantify the accuracy of electrode alignment as well as assess the accuracy of the implantation depth and the error in spatial targeting within the gray matter of the spinal cord. As proof of concept, an intraoperative ISMS experiment was also conducted in an additional live pig using the stereotactic system, and the resulting movements and electromyographic responses were recorded.RESULTSThe stereotactic system was quick to set up (< 10 minutes) and provided sufficient stability and range of motion to reach the ISMS targets reliably in the pigs. Transverse ultrasound images with the probe angled at 25°–45° provided acceptable contrast between the gray and white matter of the spinal cord. In pigs, the largest electrode alignment error using ultrasound guidance, relative to the minor axis of the spinal cord, was ≤ 3.57° (upper bound of the 95% confidence interval). The targeting error with ultrasound guidance in bench testing for targets 4 mm deep into the surrogate spinal cords was 0.2 ± 0.02 mm (mean ± standard deviation).CONCLUSIONSThe authors developed and evaluated an ultrasound-guided spinal stereotactic system for precise insertion of intraspinal implants. The system is compatible with existing spinal instrumentation. Intraoperative ultrasound imaging of the spinal cord aids in alignment of the implants before insertion and provides feedback during and after implantation. The ability of ultrasound imaging to distinguish between spinal cord gray and white matter also improves confidence in the localization of targets within the gray matter. This system would be suitable for accurate guidance of intraspinal electrodes and drug or cell injections.

Objective The overall goal of this study was to investigate the effects of various anesthetic protocols on the intraoperative responses to intraspinal microstimulation (ISMS). ISMS is a neuroprosthetic approach that targets the motor networks in the ventral horns of the spinal cord to restore function after spinal cord injury. In preclinical studies, ISMS in the lumbosacral enlargement produced standing and walking by activating networks controlling the hindlimb muscles. ISMS implants are placed surgically under anesthesia, and refinements in placement are made based on the evoked responses. Anesthesia can have a significant effect on the responses evoked by spinal neuroprostheses; therefore, in preparation for clinical testing of ISMS, we compared the evoked responses under a common clinical neurosurgical anesthetic protocol with those evoked under protocols commonly used in preclinical studies. Approach Experiments were conducted in seven pigs. An ISMS microelectrode array was implanted in the lumbar enlargement and responses to ISMS were measured under three anesthetic protocols: (1) isoflurane, an agent used pre-clinically and clinically, (2) total intravenous anesthesia (TIVA) with propofol as the main agent commonly used in clinical neurosurgical procedures, (3) TIVA with sodium pentobarbital, an anesthetic agent used mostly preclinically. Responses to ISMS were evaluated based on stimulation thresholds, movement kinematics, and joint torques. Motor evoked potentials (MEP) and plasma concentrations of propofol were also measured. Main results ISMS under propofol anesthesia produced large and functional responses that were not statistically different from those produced under pentobarbital anesthesia. Isoflurane, however, significantly suppressed the ISMS-evoked responses. Significance This study demonstrated that the choice of anesthesia is critical for intraoperative assessments of motor responses evoked by spinal neuroprostheses. Propofol and pentobarbital anesthesia did not overly suppress the effects of ISMS; therefore, propofol is expected to be a suitable anesthetic agent for clinical intraoperative testing of an intraspinal neuroprosthetic system.

Objective: Shoulder rotator muscle imbalances can contribute to subacromial impingement. The forces and movement patterns of wheelchair locomotion may contribute to these imbalances. This study attempted to determine whether National Wheelchair Basketball Association players of differing classifications had significant differences ( p ≤.05) in concentric isokinetic peak shoulder rotator torque and torque ratios, and wheelchair locomotion dependence. Design: Fifty-seven (class 1=12, class 2=24, class 3=21) of 117 total tournament participants (class 1=25, class 2=49, class 3=43) served as the convenience sample of volunteers for the survey portion, and 33 of these subjects (class 1=11, class 2=12, class 3=10) also entered the isokinetic portion of this study. Setting: National wheelchair basketball tournament. Results: Class 1 and 2 players had greater wheelchair dependence than class 3 players ( p ≤ .05). Peak torque or torque ratios generally did not differ among player classifications or with other populations. Class 1 players had weaker nondominant shoulder external rotator torque production at 60°/sec ( p ≤ .03) compared with other classes and at 180°/sec compared with class 3 players ( p = .02), suggesting an inability to develop the "attenuation of dominance" noted among other groups. Diminished torque-producing capacity at 60°/sec related to greater wheelchair dependence among class 1 players ( p = .034). Conclusions: Class 1 players failed to demonstrate the acquired shoulder external rotator torque symmetry evident among class 2 and 3 players (with specific weakness of the nondominant shoulder external rotators). This torque symmetry difference was related to their greater dependence on wheelchair locomotion.

Bilateral chylothorax following thoracic duct injury is a rare occurrence. Since 1907 there have been only six reports in the literature of this potentially serious complication. We report a case of bilateral chylothorax following ligation of the cervical thoracic duct during a left subclavian to carotid artery transposition.

Pyriform sinus cancer remains one of the most lethal of human diseases. Regardless of approach attempted significant enhancement of survival has not been realized. In this study a retrospective single institutional review of all patients diagnosed with pyriform sinus cancer during the 1980s was conducted. The results in 93 patients show an overall determinant 5-year survival of 14.3%. Of patients undergoing surgery, median determinant survival was 37 months and 5-year survival was 34.6%. In resectable patients treated with radiation with or without chemotherapy, median determinant survival was 13 months with 5-year survival of 7.1% (P