Proximal humerus fracture in adults. It is the most common fracture of the humerus, as well as the most common fracture at the shoulder girdle. They are more common in women than men, and occur more often in older adults. The average age of people who sustain a proximal humerus fracture is 63–66 years. 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
Bone marrow Bone marrow Bone marrow is a semi-solid tissue which may be found within the spongy or cancellous portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production or hematopoiesis. It is composed of hematopoietic cells, marrow adipose tissue, and supportive stromal cells. In adult humans, bone marrow is primarily located in the ribs, vertebrae, sternum, and bones of the pelvis. On average, bone marrow constitutes 4% of the total body mass of humans; in an adult having 65 kilograms of mass (143 lb), bone marrow typically accounts for approximately . Human marrow