Post-traumatic recurrent ulnar nerve dislocation at the elbow: a rare case report.

Introduction and importance: Several authors have also made reference to a less prevalent condition known in elbow as ulnar nerve subluxation. However, this particular condition tends to manifest primarily in young individuals who engage in professional sports or activities involving extensive use of the forearm. A more severe form of ulnar nerve subluxation, which is ulnar nerve dislocation, gives rise to a characteristic dislocation and relocation of the nerve at the elbow during flexion and extension of the forearm. Due to the rarity of this condition in clinical settings and its predominant occurrence as subluxation in younger patients, there are instances where traumatic ulnar nerve dislocation can be overlooked and misdiagnosed with two commonly encountered pathological conditions as ulnar nerve entrapment or medial epicondylitis. Case presentation: The authors present a 51-year-old male with chronic pain when moving his right forearm following a fall that caused a direct force injury to his elbow. The patient was misdiagnosed and treated as medial epicondylitis and early-stage ulnar nerve entrapment. However, the symptoms did not improve for a long time. The authors performed the ulnar nerve anterior transposition surgery using the subcutaneous transposition technique and the result is very good without any pain. Clinical discussion: The ulnar nerve can naturally be subluxed or dislocated if Osborne's ligament is loose or when there are anatomical variations in the medial epicondyle. In some case, this ligament can be ruptured by trauma. The symptoms of ulnar instability are caused by friction neuritis. Dynamic ultrasound of the ulnar nerve in two positions show clearly this condition. Conclusion: Post-traumatic ulnar nerve dislocation is a rare condition, and the recurrent characteristic of it leads to neuritis or neuropathy. The condition can be overlooked or misdiagnosed as medial epicondylitis or early-stage ulnar nerve entrapment. The nerve transposition surgery will give good result.

Development of taste-masking microcapsules containing azithromycin by fluid bed coating for powder for suspension and in vivo evaluation.

This research aims to develop bitter taste-masking microcapsules containing azithromycin (AZI) by a simpler and familiar method, fluid-bed coating technology, in comparison with Zithromax®. Cores of microcapsules, AZI microparticles, were prepared by fluid-bed granulation, then taste-masking polymer was covered on by fluid-bed coating technique. Eudragit L100, Eudragit RL100, and ethyl cellulose in single and combined with Eudragit L100 and Eudragit E100 were used as taste-masking polymers. The obtained microcapsules were characterised by taste-masking ability, in vitro release, SEM, coating thickness, and coating efficiency. Combination of ethyl cellulose and Eudragit E100 (3:1) in coating thickness of 45.13 ± 2.12% w/w prevents AZI release from microcapsules below bitter taste threshold (1.78 ± 1.17 µg/ml). Bioavailability of powders containing AZI microcapsules and pH modulators (50 mg Na3PO4 and 35 mg Mg(OH)2) was not significantly different from the reference product (Zithromax®, Pfizer, New York, NY) in the rabbit model (p > 0.05). These results support the possibility of developing a generic product containing AZI.

COVID-19 pandemic and herd behavior: Evidence from a frontier market.

This paper examines the presence of herd behavior in the Vietnamese stock market using the cross-sectional absolute deviation (CSAD) method and by applying quantile regression (QR). We detect herd behavior in the Vietnamese stock market from January 2016 to May 2022. Herd behavior is less pronounced for bullish markets, yet more prominent under other market conditions. Importantly, the paper provides insight into the herd phenomenon during COVID-19's fourth wave outbreak in Vietnam. We discover that during the fourth wave outbreak, investors on the Hanoi Stock Exchange (HNX) do not engage in herding. However, herd behavior does manifest on the Ho Chi Minh Stock Exchange (HOSE) with falling stock prices engendering pessimistic herd selling. Knowledge of this empirical evidence of herd behavior in the Vietnamese stock market should prove useful to investors in determining the intrinsic value of stocks, and to policymakers wishing to enhance the efficiency of the equity market.

Reverse shoulder megaprosthesis replacement for aggressive aneurysm bone cyst of proximal humerus: Case report and literature review.

INTRODUCTION: and importance: Wide resection in the surgical treatment of aneurysms bone cysts is often performed in cases where the tumor is large, recurrent, growing, and intensely invasive. Reshaping the defect after tumor removal is a necessary issue to restore shape and maintain function for the patient. CASE PRESENTATION: A 26-year-old male patient, diagnosed with an aneurysm bone cyst in the proximal humerus, underwent surgery for curettage and bone grafting twice. After surgery, there was still pain in the shoulder area, the tumor progressed aggressively with limited shoulder movement. Based on the imaging re-evaluation, it was shown that the tumor increased rapidly in size, invaded the soft tissue, and completely changed the normal structure of the shoulder joint, and the proximal humerus. We used a reverse shoulder joint with an additional module to restore the bone defect of the tumor and the function of the shoulder joint. Follows-up showed that patient no longer pain in shoulder area, shoulder joint function recovery is progressing well, Musculoskeletal Tumor Society (MSTS) score is 25 & 28, shoulder joint function score according to ASES scale: 80 & 93.33 respectively at 3 months and 6 months after surgery. CLINICAL DISCUSSION: Aggresive aneurysm bone cyst of proximal humerus is not common and still a challenge to the treatment. Due to the bone and joint destruction, the indication of tumor resection and reconstruct the joint and bone loss is required. Among several solution, reverse shoulder megaprosthesis is a newest one can favor the purpose of our treatment. Up to now, this solution is mainly used to preserving for malignant bone tumor. CONCLUSIONS: Tumor wide resection with modular reverse shoulder replacement with the modular segment is a reasonable intervention option in cases of large aneurysm bone cysts, with rapid recurrence, aggressive progression, and soft tissue invasion.

Novel technique for scapulothoracic arthroscopy: A case report of the application of intraoperative 3D imaging.

INTRODUCTION: Snapping shoulder syndrome could be effectively treated with scapulothoracic arthroscopy. The excision of the scapular superomedial corner is assumed to help lower the recurrence rate. However, the amount of resection is still controversial. Furthermore, we lack a technique to measure if the resected amount was adequate based only on arthroscopy evaluation. CASE STUDY PRESENTATION: We describe a 47-year-old man who suffered from severe snapping shoulder syndrome as a consequence of a deformity of the left superomedial scapular corner. The patient had endoscopic bursectomy and superomedial corner resection. Intraoperative three-dimensional CT scans (3D-CT) were used to evaluate the amount of resection. The patient recovered without incident and resumed his usual activities within 30 days following surgery. At the six-month follow-up, there were no recurrent symptoms. CONCLUSION: Intraoperative 3D imaging significantly enhances the safety and efficacy of scapulothoracic arthroscopy. This is a novel technique that, to our knowledge, has not been reported previously in the literature.

Non-oncologic indication for elbow megaprothesis replacement: 2 cases report.

INTRODUCTION: Treatment of elbow bone defects is still a huge challenge in orthopaedic in order to restore the shape and function of the elbow joint. Bone defect reconstruction is very difficult due to biomechanical complexity of the elbow joint and the poor coverage tissue of this area, so mega-prothesis can be considered the most optimal solution in these cases. CASE REPORT: We present two clinical cases of megaprosthesis elbow replacement for treatment of bone defects caused by sequelae of trauma. There is one case of 3 cm bone defect at proximal ulna and one case of 3 cm bone defect at distal humerus. In the 1st case, the elbow joint is fusioned and the second case, the elbow joint is degenerated totally after 3 previous surgery. We performed total elbow replacement with a customized megaprosthesis for them. The Mayo elbow function assessment scale [1] pre-surgery was poor at 50 points. The average age is 35 years old. The mean post-operative follow-up time was 14 months. Range of elbow flexed motion was 135 degrees, both patients were maximally extension, the forearm pronation and supination were 90 and 75 degrees, respectively. The Mayo score is very good with 97,5 points. Both patients were completely satisfied with the postoperative results. CONCLUSION: Our results show that megaprosthesis elbow replacement is a very effective option for cases large elbow bone defects due to trauma sequelae. However, careful preoperative preparation is required for the best outcome.