[Functional Outcome of Peripheral Nerve Injury after Pediatric Supracondylar Humerus Fracture: Comparison of Surgical and Conservative Treatment]. / Funktionelle Ergebnisse peripherer Nervenverletzungen nach kindlichen suprakondylären Humerusfrakturen: Vergleich operativer und konservativer Behandlung.

Supracondylar humerus fractures are the most common elbow fractures in children up to 10 years of age. The incidence of associated nerve injuries varies up to 15% depending on the data. Traumatic and iatrogenic lesions mainly affect the ulnar nerve. The regeneration of peripheral nerves is comparatively better in childhood. In the present study, the functional results after surgical and conservative treatment of nerve injuries in children after supracondylar fractures were compared and analyzed for influencing factors. In this retrospective comparative study, clinical data of pediatric nerve injuries following supracondylar humerus fractures treated over a period of 13 years (2008-2021) were analyzed. Children who were treated surgically (neurolysis, autologous reconstruction) due to insufficient clinical/neurophysiological improvement within 6 months after trauma or who were followed up conservatively in case of regression of symptoms within 6 months after trauma were included. All patients underwent multidisciplinary follow-up. 48 patients (26 female/22 male) with nerve injuries were included in this study. All patients had a history of surgical treatment with K- wire fixation due to severe dislocated fractures. The mean age was 7±2 years. The initial symptoms were severe motor deficits in all patients and sensory deficits in 87.5% (n=42). Isolated lesions of the ulnar nerve were most common (n=24, 50%). The nerve was neurolysed in 21 patients and additionally transferred to the volar side in 15. Nerve grafting was performed in 7 children and split repair in 2. Postoperatively, there was a significant improvement in motor function in all patients. Despite comparably severe motor deficits at initial presentation, further 20 children were treated conservatively due to the regression of neurological deficits. They showed comparably good functional results. No serious complications were recorded in either group. The average follow-up time was 377.25±524.87 days. The presented study shows excellent functional results after surgical treatment of pediatric nerve injuries without severe complications. Children with comparatively high-grade lesions at initial presentation have a good chance of complete spontaneous remission even without surgery. For this reason, the indication for surgery in children should be very carefully considered.

Motoneuron-Specific PTEN Deletion in Mice Induces Neuronal Hypertrophy and Also Regeneration after Facial Nerve Injury.

In postmitotic neurons, several tumor suppressor genes (TSGs), including p53, Rb, and PTEN, modulate the axon regeneration success after injury. Particularly, PTEN inhibition is a key driver of successful CNS axon regeneration after optic nerve or spinal cord injury. In contrast, in peripheral neurons, TSG influence in neuronal morphology, physiology, and pathology has not been investigated to the same depth. In this study, we conditionally deleted PTEN from mouse facial motoneurons (Chat-Cre/PtenloxP/loxP ) and analyzed neuronal responses in vivo with or without peripheral facial nerve injury in male and female mice. In uninjured motoneurons, PTEN loss induced somatic, axonal, and nerve hypertrophy, synaptic terminal enlargement and reduction in physiological whisker movement. Despite these morphologic and physiological changes, PTEN deletion positively regulated facial nerve regeneration and recovery of whisker movement after nerve injury. Regenerating PTEN-deficient motoneurons upregulated P-CREB and a signaling pathway involving P-Akt, P-PRAS40, P-mTOR, and P-4EBP1. In aged mice (12 months), PTEN deletion induced hair loss and facial hyperplasia of the epidermis. This suggests a time window in younger mice with PTEN loss stimulating axon growth after injury, however, at the risk of hyperplasia formation at later time points in the old animal. Overall, our data highlight a dual TSG function with PTEN loss impairing physiological neuron function but furthermore underscoring the positive effects of PTEN ablation in axon regeneration also for the PNS.SIGNIFICANCE STATEMENT Tumor suppressor genes (TSGs) restrict cell proliferation and growth. TSG inhibition, including p53 and PTEN, stimulates axon regeneration after CNS injury. In contrast, in PNS axon regeneration, TSGs have not been analyzed in great depth. Herein we show enhanced peripheral axon regeneration after PTEN deletion from facial motoneurons. This invokes a signaling cascade with novel PTEN partners, including CREB and PRAS40. In adult mice, PTEN loss induces hyperplasia of the skin epidermis, suggesting detrimental consequences when reaching adulthood in contrast to a beneficial TSG role for regeneration in young adult mice. Thus, our data highlight the double-edged sword nature of interfering with TSG function.

Similarity of coagulation and inflammation despite different surgical revascularization strategies - a prospective randomized trial.

BACKGROUND:: Supposedly, minimized extracorporeal circulation or off-pump revascularization as alternatives to conventional extracorporeal circulation (ONCAB) reduce inflammation and coagulation disturbances. METHODS:: One hundred and twenty coronary artery bypass graft (CABG) patients were prospectively randomized for three surgical techniques. Coagulation and inflammation markers were measured up to 72 hours postoperatively. RESULTS:: Coagulation factors I, II, V, X, antithrombin III and C-reactive protein did not differ perioperatively between the groups and increased, as did several other markers, 12 to 72 hours postoperatively. Compared to its alternatives, ONCAB showed the most obvious transient increase in thrombin-antithrombin complexes (p<0.0001), D-dimers (p=0.0059), tissue factor pathway inhibitor (p=0.0005), factor VIII (p=0.0041) and tumor necrosis factor α (p=0.0300) during the operation and up to 12 hours postoperatively. Furthermore, ONCAB generated lower leukocyte and platelet counts and higher values of soluble P-selectin and soluble intercellular adhesion molecule 1 at some time points. CONCLUSIONS:: With similarity in pivot coagulation factors, a specific detrimental influence of ONCAB on common coagulation pathways was excluded. Higher perioperative concentrations of products from the coagulation cascade most likely indicate activation of pericardial blood - recirculated only in ONCAB. Furthermore, with only temporary differences in markers of inflammation, the alternatives to ONCAB altogether were without advantage at 72 hours postoperatively. In the general answer to surgical trauma, the part of modern extracorporeal circulation is possibly overestimated. The study is registered at the German Clinical Trial Registry. Registration number DRKS00007580. URL: https://drks-neu.uniklinik-freiburg.de/drks_web/ URL: http://apps.who.int/trialsearch/.

Renal Function and Urinary Biomarkers in Cardiac Bypass Surgery: A Prospective Randomized Trial Comparing Three Surgical Techniques.

Background Cardiopulmonary bypass procedure is associated with an increased risk of renal impairment. To which extent structural damage causes functional decline is unknown. We evaluated perioperative kidney injury and function in patients treated with conventional extracorporeal circulation (CECC), minimized extracorporeal circulation (MECC), and off-pump coronary artery bypass grafting (OPCAB). Methods Blood and urine samples, collected at baseline and up to 72 hours after surgery from patients of the HEPCON trial (DRKS00007580, 120 patients randomized for heparin management and for surgical technique), were analyzed for differences in renal injury and function. Neutrophil gelatinase-associated lipocalin, α glutathione S-transferase, liver fatty acid-binding protein, and kidney injury molecule-1 were measured as urinary protein markers of renal tubular injury. Serum creatinine, blood urea levels, and estimated glomerular filtration rate were determined to monitor renal function. Results Markers of tubular injury differed significantly between surgical technique groups early after surgery, indicating the most detrimental effect in CECC. Hemolysis and hemodilution correlated with these early changes. A late rise did not show intergroup differences. Time courses of renal function parameters, as well as the development of acute kidney injury in 15 patients (13.5%), were irrespective of surgical technique. Heparin management did not influence renal parameters. Conclusion During coronary artery bypass grafting, CECC temporarily induces more tubular injury than MECC or OPCAB. However, late changes of renal function parameters occur irrespective of extracorporeal perfusion mode and even in off-pump surgery.