Inclusion criteria:	General: Male or female older than 18 and younger than 65 years; Communication in German or English possible; Signed declaration of consent. Nerve pathologies: Fresh (<96 h) open–traumatic nerve injuries to the trunk nerves of the upper extremity: radial, ulnar, median, musculocutaneous nerves, and their branches from the brachial plexus to the distal end of the carpal tunnel. Osteosynthesis: Patients with an MRT-compatible plate fixation using a tita-nium plate of the upper extremity; Humeral fracture; No nerve lesion necessary.
Exclusion criteria	Rejection of study participation; Age <18 or >65 years;∙ Failure to show up for a follow-up examination; Patients who are unable to provide information or who are unconscious; Simultaneous participation in another study to evaluate a drug or medical device; Vitally threatening injury upon initial diagnosis (e.g., multiple trauma); Insufficient knowledge of German or English; Mental health issues, which limits patients’ capacity to consent (e.g., acute psychosis, dementia); Pregnancy, breastfeeding; Ongoing immunosuppressive or antineoplastic therapy.
Absolute contraindications to MRI	Pacemaker; Mechanical heart valves; Brain and spinal cord stimulators as well as most other electrical stimulating devices implanted in the body; Insulin pumps or other drug pumps; Ventriculoperitoneal shunts (VP shunts); Cochlear implants; Foreign metal bodies in the soft tissues of the body, e.g., in the eyes, in the abdominal or chest cavity; Obesity, which prevents the use of the MRI; Upper-limb immobility that prevents an MRI scan.
In the case of a relative contraindication, only after the patient has been informed and the radiologist performing the procedure has given their consent	Claustrophobia; Prosthetic joint replacement; Tattoos; Piercings; Vascular stents, e.g., in the coronary arteries.