Trans-fracture transposition of the radial nerve during the open approach of humeral shaft fractures

The radial nerve constitutes a major problem in humeral shaft fractures; it may be injured immediately or during closed reduction or open reduction and internal fixation with plate and screws. After fixation, the nerve always runs directly over the plate without any interposed structure. If a revision surgery is indicated, the nerve is at high risk as it is usually difficult to dissect from surrounding fibrotic scar tissue or callus formation. To avoid these complications, some authors reported transposition of the radial nerve through the fracture line. We present herein the surgical technique of the trans-fracture transposition of the radial nerve during open reduction and internal fixation of humeral shaft fractures, along with our preliminary results in 6 cases and a review of the literature.     

Irreducible volar dislocation of the proximal interphalangeal finger joint

Volar dislocation of the proximal interphalangeal finger joint is rare. The trauma that causes this injury consists in a rotation mechanism in almost all cases. It may be initially missed and diagnosed at a late sequel stage. Closed reduction should always be attempted first but this procedure may result in failure, necessitating a surgical intervention. In irreducible cases, the surgical investigation shows a longitudinal split which separates one of the lateral bands (ulnar or radial) from the central slip of the terminal extensor tendon. In addition, the lateral band is displaced to the volar aspect of the head of the first phalanx, and partially entrapped into the proximal interphalangeal joint, the head of the first phalanx being trapped between the central slip and the displaced lateral band. Surgical relocation of the displaced lateral band gives an immediate reduction of the dislocated joint. We present a case of irreducible dislocation of the proximal interphalangeal joint of the right index finger in a 42-year-old female patient who required a surgical treatment. We present the diagnostic, anatomic and therapeutic aspects of this rare injury, together with a review of the literature.     

Traumatic posterior shoulder dislocation: a case with modification of Gerber procedure for humeral head reconstruction at 10-year follow-up

We report a case of acute traumatic posterior shoulder dislocation in a 41-year-old patient, which we treated surgically by a modification of the procedure described by Gerber for humeral head reconstruction in such cases. The diagnosis was confirmed by CT scan, which also helped us to assess the size of the antero-medial humeral head defect or impaction secondary to the dislocation; the size of this defect being a determinant element for the indication. Because the shoulder was unstable after closed reduction and almost 50% of the humeral head was impacted, we carried out a surgical treatment using an original technique as mentioned above. Radiologic and surgical features of acute traumatic posterior shoulder dislocation are discussed with special emphasis on diagnosis, indications and surgical aspects of this rare lesion, which represent 2–4% of acute traumatic shoulder dislocations.     

Posterolateral rotatory instability of the elbow secondary to sprain

We present a case of a 23 year-old man who presented to the emergency department after sustaining indirect trauma to the left elbow with unremarkable physical examination and normal radiographs. He presented again three weeks after with repeated episodes of locking and snapping of the left elbow occurring every time he attempted to rise from a chair while pushing the armrests, and when manoeuvring the steering wheel of his vehicle. On physical examination, the patient was apprehensive to the "lateral pivot shift" test as described by O'Driscoll et al. (1991) [1]. MRI of the left elbow demonstrated avulsion of the proximal epicondylar insertion of the lateral collateral ligament complex (LCLC). The "lateral pivot shift test" was positive under general anaesthesia. Lateral elbow radiograph taken during the test showed widening of the ulno-humeral joint space with posterior subluxation of the radial head. The patient underwent surgical treatment for posterolateral rotatory instability (PLRI) of the elbow. This case report aims to highlight the clinical aspects of the PLRI which may occur after a simple elbow sprain and be easily missed if not suspected; it also aims to draw attention to the importance of the "lateral pivot shift test" and the value of the stress lateral elbow radiograph in establishing the diagnosis of this rare and subtle entity.     

A novel missense mutation in the ESRRB gene causes DFNB35 hearing loss in a Tunisian family

Autosomal recessive non-syndromic hearing loss (ARNSHL) is a genetically heterogenous disorder with 41 genes so far identified. Among these genes, ESRRB whose mutations are responsible for DFNB35 hearing loss in Pakistani and Turkish families. This gene encodes the estrogen-related receptor beta. In this study, we report a novel mutation (p.Y305H) in the ESRRB gene in a Tunisian family with ARNSHL. This mutation was not detected in 100 healthy individuals. Molecular modeling showed that the p.Y305H mutation is likely to alter the conformation of the ligand binding-site by destabilizing the coactivator binding pocket. Interestingly, this ligand-binding domain of the ESRRB protein has been affected in 5 out of 6 mutations causing DFNB35 hearing loss. Using linkage and DHPLC analysis, no more mutations were detected in the ESRRB gene in other 127 Tunisian families with ARNSHL indicating that DFNB35 is most likely to be a rare type of ARNSHL in the Tunisian population.     

Weekly Nowcasting of New COVID-19 Cases Using Past Viral Load Measurements

The rapid spread of the coronavirus disease COVID-19 has imposed clinical and financial burdens on hospitals and governments attempting to provide patients with medical care and implement disease-controlling policies. The transmissibility of the disease was shown to be correlated with the patient’s viral load, which can be measured during testing using the cycle threshold (Ct). Previous models have utilized Ct to forecast the trajectory of the spread, which can provide valuable information to better allocate resources and change policies. However, these models combined other variables specific to medical institutions or came in the form of compartmental models that rely on epidemiological assumptions, all of which could impose prediction uncertainties. In this study, we overcome these limitations using data-driven modeling that utilizes Ct and previous number of cases, two institution-independent variables. We collected three groups of patients (n = 6296, n = 3228, and n = 12,096) from different time periods to train, validate, and independently validate the models. We used three machine learning algorithms and three deep learning algorithms that can model the temporal dynamic behavior of the number of cases. The endpoint was 7-week forward number of cases, and the prediction was evaluated using mean square error (MSE). The sequence-to-sequence model showed the best prediction during validation (MSE = 0.025), while polynomial regression (OLS) and support vector machine regression (SVR) had better performance during independent validation (MSE = 0.1596, and MSE = 0.16754, respectively), which exhibited better generalizability of the latter. The OLS and SVR models were used on a dataset from an external institution and showed promise in predicting COVID-19 incidences across institutions. These models may support clinical and logistic decision-making after prospective validation.     

Traitement chirurgical des granulomes éosinophiles solitaires de la voûte du crâne. À propos de deux cas

Langerhans cell histiocytosis is a systemic disease resulting from the oligoclonal proliferation of Langerhans cells, occurring most commonly in children and young adults. The focal form of the disease, also known as eosinophilic granuloma, most frequently involves the calvaria. We present two cases of calvarial eosinophilic granulomas that were surgically removed. These tumors are reputed to have an excellent prognosis, even if local recurrences and systemic dissemination can occur during the follow-up. The authors discuss the pathogenesis and the evolutive profile but also the therapeutic management of solitary eosinophilic granuloma of the calvaria.     

Fracture of trapezium with trapeziometacarpal subluxation

Fractures of trapezium are reportedly rare, less than 5% of all carpal bones fractures. A vertical sagittal fracture type is encountered in about 20% of cases. This fracture type is unstable and is usually displaced like a Bennett’s fracture. Open reduction and internal fixation is admitted to be the best method of treatment, but it has always been augmented with a postoperative cast immobilization to temporary stabilize the trapeziometacarpal joint. We describe a case of displaced vertical sagittal fracture of the trapezium with trapeziometacarpal subluxation treated by open reduction and internal fixation of the trapezial fracture, associated with temporary stabilization of the trapeziometacarpal joint using two percutaneous intermetacarpal Kirschner wires.