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OBJECTIVES: The objective of this study was to evaluate unplanned cortical or neuroforaminal violation of iliosacral and transsacral screw placement using fluoroscopy versus screw placement using a robotic arm. DESIGN: This is a prospective cohort study. SETTING: Single surgeon, single North American level 1 trauma center. PATIENTS: Radiographic and clinical data for 21 consecutive adult trauma patients with pelvic ring fractures undergoing surgical treatment were prospectively collected. Treatment consisted of iliosacral and/or transsacral screws with or without anterior fixation. INTERVENTION: Ten patients were treated with the assistance of a robotic arm. Eleven patients were treated with standard fluoroscopic techniques. MAIN OUTCOME MEASUREMENTS: Thirty-two screws were placed and evaluated with postoperative computed tomography or O-arm spins to assess unplanned cortical or neuroforaminal violation. Violations were graded according to the Gertzbein and Robbins system for pedicle screw violation, categorizing screw violation in 2-mm increments. The postoperative images were blindly reviewed by 5 fellowship-trained orthopaedic traumatologists. The treating surgeon was excluded from review. RESULTS: The Mann-Whitney U test on the Gertzbein and Robbins system results demonstrated significantly (P = 0.02) fewer violations with robotic assistance. χ2 analysis of whether there was a cortical violation of any distance demonstrated significantly (P = 0.003) fewer cortical violations with robotic assistance. There were no neurovascular injuries in either group. CONCLUSION: Robotic assistance demonstrated significantly fewer unplanned cortical or neuroforaminal violations. Further research is needed with additional surgeons and sites to evaluate the accuracy of iliosacral and transsacral screw placement with robotic assistance. LEVEL OF EVIDENCE: Therapeutic, level II.

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PURPOSE: The use of a robotic arm has been well-described in the literature for the placement of pedicle screws in spine surgery as well as implants for sacroiliac joint fusion. There are no reports describing the use of a robotic arm to place screws in osseous fixation pathways (OFPs) employed in the treatment of pelvic ring and acetabular fractures outside of a single center in China. Using a Sawbones model, the authors describe a technique for using a robotic arm widely available in Europe and the Americas for placement of 6.5 mm cannulated screws into two OFPs commonly used in the treatment of pelvic and acetabular fractures. METHODS: Using the Mazor X Stealth Edition (MSXE) robot from Medtronic, the authors were able to place a pin into the pelvis onto which the robot was docked. The authors were then able to designate the area of interest using navigated instruments, and in combination with the MSXE "scan and plan" marker, obtain cross-sectional imaging using the O-Arm and successfully register the MSXE robot. We then used the provided software to plan trajectories for the lateral compression type 2 (LC-II) screw pathway as well as a pathway for a trans-ilio-trans-sacral screw. We describe in detail the steps for setup, planning and placement of 6.5 mm cannulated screws using the MSXE robotic arm into these two OFPs. RESULTS: Visual inspection and plain x-rays demonstrated successful placement of the screws into the two planned OFPs. No breach of cortical bone was seen on either visual inspection of the model or demonstrated on post-procedure x-rays. CONCLUSION: It is possible to use the Mazor X Stealth Edition robot to place screws into the LC-II and trans-ilio-transsacral screw pathways in a Sawbones model. This is only a feasibility study, and should in no way be taken to suggest that clinical application of this technique should be attempted.

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A series of CuCe-modified TiO2-ZrO2 catalysts synthesized by stepwise impregnation method and ultrasonic-assisted impregnation method were investigated to research the removal of NO in the simulated flue gas. Results showed that the CuCe/TiO2-ZrO2 catalyst prepared by ultrasonic-assisted impregnation method exhibited the superior NO conversion, in which higher than 85% NO was degraded at the temperature range of 250-400 °C and the highest NO conversion of 94% at 350 °C. It proves that ultrasonic treatment can markedly improve the performance of catalysts. The effect of ultrasonic enhancement on CuCe/TiO2-ZrO2 was comprehensively studied through being characterized by physicochemical characterization. Results reveal that the ultrasonic cavitation effect improves the distribution of active species and the synergistic interaction between Cu with Ce components (Cu+ + Ce4+ â†” Cu2+ + Ce3+) on the catalysts significantly, thus resulting in better dispersibility as well as a higher ratio of Cu2+ and Ce3+ of the catalysts. Moreover, it was found that the CuCe/TiO2-ZrO2 catalyst prepared by the ultrasonic-assisted impregnation method represented a higher degree of ultrafine metal particles and evenness. The above results were described with the generalized dimension and singularity spectra in multifractal analysis and validated by the comparative test. Therefore, it can be concluded that ultrasonic treatment facilitates the particle size and distribution of active sites on the catalysts.

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We designed multiple nerve transfers in one surgery to restore active pick-up function in patients with total brachial plexus avulsion injuries. Forty patients with total brachial plexus avulsion injuries first underwent multiple nerve transfers. These included transfer of the accessory nerve onto the suprascapular nerve to recover shoulder abduction, contralateral C7 nerve onto the lower trunk via the modified prespinal route with direct coaptation to restore lower trunk function and onto the musculocutaneous nerve with interpositional bridging by medial antebrachial cutaneous nerve arising from lower trunk to restore elbow flexion, and the phrenic nerve onto the posterior division of lower trunk to recover elbow and finger extension. At least three years after surgery, the patients who had a meaningful recovery were selected to perform secondary reconstruction to restore active pick-up function. Active pick-up function was successfully restored in ten patients after they underwent multiple nerve transfers combined with additional secondary functional hand reconstructions. LEVEL OF EVIDENCE: IV.

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BACKGROUND: Magnetic resonance imaging (MRI) is the preferred study of choice for pectoralis major ruptures. Because this is a rare injury, no large case series have evaluated the efficacy of MRI for diagnosing and characterizing pectoralis major ruptures. We hypothesized that MRI would be accurate for diagnosis of the location and grade of pectoralis major tears. METHODS: The study included 36 operative cases of pectoralis major ruptures with detailed descriptions of tear location and grade and satisfactory preoperative MRIs. Two musculoskeletal fellowship-trained radiologists interpreted the MRIs, which were then compared with the operative findings for location: tendon-bone junction or myotendinous junction, and tear grade (G): G2 (incomplete high grade partial tear) or G3 (complete tear). The sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: The MRI sensitivity was 1.00 for diagnosing complete G3 tears at the sternal head and clavicular head in acute ruptures. The sensitivity of MRI for diagnosing tendon-bone tears at the sternal and clavicular heads was 0.93 and 0.90, respectively. The sensitivity of MRI in diagnosing myotendinous and G2 tears diminishes, but specificity and negative predictive value remain high for sternal and clavicular head ruptures. CONCLUSIONS: Our data support the use of MRI in diagnosing the tear grade and location of pectoralis major tendon ruptures, particularly for acute, tendon-bone, and G3 tears. The diagnostic accuracy of MRI decreases when chronic tears are evaluated. MRI remains a useful adjunct in diagnosing and guiding treatment of pectoralis major ruptures.

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BACKGROUND: To overcome the mismatch in nerve sizes in phrenic nerve transfer to the radial nerve for elbow and finger extension reanimation for patients with total brachial plexus injuries (TBPI), a selective neurotization procedure was designed. OBJECTIVE: To investigate the long-term results of phrenic nerve transfer to the posterior division of the lower trunk with direct coaptation in restoring elbow and finger extension after TBPI. METHODS: Phrenic nerve was transferred to and directly coapted with the posterior division of the lower trunk in 27 patients with TBPI. Seven patients were <18 years old (adolescent group), and the remaining 20 patients ≥18 years (adult group). RESULTS: Postoperative mean follow-up period was 54 ± 9 months (range, 48-85 months). The motor function attained M3 or greater in 81.5% of patients for elbow extension and in 48% of patients for finger extension. The percentage of patients who regained M3 or greater muscle power of finger extension in the adolescent group and the adult group was 71.4%, and 40%, respectively. Meanwhile, 85.7% in the adolescent group and 80% in the adult group achieved M3 or greater muscle power of elbow extension. There were no significant differences between the 2 groups. The elbow extension and finger extension were synchronous contractions and did not become independent of respiratory effort. CONCLUSION: This procedure simultaneously and effectively restores the function of elbow and finger extension in patients after TBPI. However, the patients could not do elbow and finger extension separately.

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Purpose. Hand infections are common, usually resulting from an untreated injury. In this retrospective study, we report on hand infection cases needing surgical drainage in order to assess patient demographics, causation of infection, clinical course, and clinical management. Methods. Medical records of patients presenting with hand infections, excluding post-surgical infections, treated with incision and debridement over a one-year period were reviewed. Patient demographics; past medical history; infection site(s) and causation; intervals between onset of infection, hospital admission, surgical intervention and days of hospitalization; gram stains and cultures; choice of antibiotics; complications; and outcomes were reviewed. Results. Most infections were caused by laceration and the most common site of infection was the palm or dorsum of the hand. Mean length of hospitalization was 6 days. Methicillin-resistant Staphylococcus aureus, beta-hemolytic Streptococcus and methicillin-susceptible Staphylococcus aureus were the most commonly cultured microorganisms. Cephalosporins, clindamycin, amoxicillin/clavulanate, penicillin, vancomycin, and trimethoprim/sulfamethoxazole were major antibiotic choices. Amputations and contracture were the primary complications. Conclusions. Surgery along with medical management were key to treatment and most soft tissue infections resolved without further complications. With prompt and appropriate care, most hand infection patients can achieve full resolution of their infection.

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BACKGROUND: Vascularized tissue transfer pedicled with the first dorsal metatarsal artery is commonly used in the microsurgical reconstruction of tissue defect. However, there are great anatomical variations of the artery. In this study, the authors classified the artery based on its origin (from where it arises), branches, and course. The significance of this classification system related to harvesting a first dorsal metatarsal artery-based tissue transfer is also discussed. METHODS: Fresh tissue dissection (n = 48) and cast specimens (n = 30) were studied. Three-dimensional reconstruction (n = 5) was performed based on the computed tomography angiogram of the adult feet. Ultrasound color Doppler imaging was performed on 340 feet. The anatomy of first dorsal metatarsal artery was also studied in patients (n = 148) who had surgery on the first web space. RESULTS: The intramuscular type of the artery described by Gilbert was not found in any of the study specimens. The most common type was found in the space between the dorsal interosseous muscle and the first metatarsal. The authors thus propose a new classification system for the first dorsal metatarsal artery: the arises (origin), branch, and course (ABC) classification system. CONCLUSION: The arises (origin), branch, and course classification system can help a surgeon to better understand the anatomical variations of the first dorsal metatarsal artery and harvest vascularized tissues based on the artery.

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