Proximal humerus fracture Proximal humerus fracture A proximal humerus fracture is a break of the upper part of the bone of the arm (humerus). Symptoms include pain, swelling, and a decreased ability to move the shoulder. Complications may include axillary nerve or axillary artery injury. The cause is generally a fall onto the arm or direct trauma to the arm. Risk factors include osteoporosis and diabetes. Diagnosis is generally based on X-rays or CT scan. It is a type of humerus fracture. A number of classification systems exist. Treatment is generally with an arm sling for a brief period of time followed by
Bone marrow the umbilical cord. The earliest fossilised evidence of bone marrow was discovered in 2014 in "Eusthenopteron", a lobe-finned fish which lived during the Devonian period approximately 370 million years ago. Scientists from Uppsala University and the European Synchrotron Radiation Facility used X-ray synchrotron microtomography to study the fossilised interior of the skeleton's humerus, finding organised tubular structures akin to modern vertebrate bone marrow. "Eusthenopteron" is closely related to the early tetrapods, which ultimately evolved into the land-dwelling mammals and lizards of the present day. Bone marrow Bone marrow is a semi-solid tissue which may be found within the spongy or