M3D1

Following a severe spinal cord injury in the lumbar region, the voluntary muscles of the legs and hips will be paralyzed. Describe the effects of paralysis on the skeleton.

Lumbar spinal nerves (L1 to L5) emerge from the spinal cord in the low back and control signals to the lower parts of the abdomen and the back, the buttocks, some parts of the external genital organs, and parts of the leg. As a result of the severe spinal cord injury to the lumbar region, the body loses its ability to control the muscles from the waist down, loss of physical sensation, bowel, bladder, and sexual dysfunction can occur. The shoulders, arms, and hand functions are usually unaffected. As a result of the loss of movement, many effects take place on the body. When weight bearing and muscle contraction cease after spinal cord injuries, bone reabsorption outpaces bone formation, eventually resulting in neurogenic osteoporosis. Because of the immobility, this causes our bone-producing cells (osteoblasts) to slow bone deposition, resulting in decreased bone mass (osteopenia). Also, the lack of activity and building of protein (that would be used for exercise, contractions, etc.) could lead to rigid body dysmorphia. Additionally, the lack of exercises changes the bone matrix, and the body may attempt to perform osteoclastic activity and therefore lowering blood calcium levels and depleting bone in the affected areas.

A 5 month old infant is brought to a clinic after having diarrhea for 2 days. The nurse checks the baby’s anterior fontanel and notices that it appears sunken. What has caused this?

Sunken Fontanels are areas on a baby's head that allow for compression and development of the skull. It is made up of fibrous connective tissue and can be found on the top of the skull (frontal) and the side of the head (parietal). Typically, these areas close approximately 18-24 months after birth. At this time, these areas are ossified and fortified. When fontanels are sunken...