Mrs. Debbie Morgan is a 45-year-old female who works as astocking clerk for a local home improvement store. While she was atwork today a large box of metal rivets fell from a 20-ft.-highoverhead shelf, striking her outstretched arm and knocking her tothe ground. The ambulance personnel reported that she had lostquite a bit of blood at the accident scene and was “knocked out”when they arrived. To minimize further hemorrhage, the paramedicsapplied a pressure bandage to her arm.

You meet the paramedics as they bring Mrs. Morgan into theemergency room and begin to assess her for injuries. She is awakeand alert, but complaining of severe left arm and back pain, plusshe has a “killer headache.” To fully examine her injuries youremove four blood-soaked bandages from her arm. You notice a largeopen wound on her arm with what appears to be bone tissue stickingout of the skin. She also has bruises covering her left shoulder,left wrist, and lower back. To determine the extent of her injuriesMrs. Morgan undergoes several x-rays, which reveal thefollowing:

1) fracture of the left humerus at the proximal diaphysis,

2) depressed fracture of the occipital bone,

3) fracture of the 3rd lumbar vertebral body.

Short Answer Questions

Define the following terms, used in the case and also inassociated questions (1 point each):

1. hemorrhage
2. fracture
3. proximal
4. diaphysis

1. One way bones are classified is by their shape. How would youclassify the bones fractured by Mrs. Morgan (3points)?

1. The body of Mrs. Morgan’s vertebra is fractured. What type ofbone tissue makes up the majority of the vertebral body (1point)? Describe the structure and function of this typeof bone (2 points).

1. The diaphysis of Mrs. Morgan’s humerus is fractured. What typeof bone tissue makes up the majority of the diaphysis of long boneslike the humerus (1 point)? List anddescribe/define the layers (lamellae) of bone tissue found here(3 points).

1. Most connective tissue, including bone, is highly vascular.Which anatomical structures in Mrs. Morgan’s compact bone houseblood vessels (2 points)? What sign or symptom inMrs. Morgan’s case is directly related to disruption of thesestructures by her bone fractures (1 point)? How isthe sign or symptom related to these anatomical structures(1 point)?

1. Within days after a fracture, a “soft callus” of fibrocartilageforms. What fibers are found in this type of cartilage (1point)? Identify the cells required for fibrocartilaginouscallus formation and list their functions (2points).

1. As a fracture is repaired, new bone is added to the injurysite. What term is used to describe the addition of new bone tissue(1 point)? Identify which bone cell is responsible for this process(1 point)and explain how it occurs (2points).

1. In the final stage of bone repair, some of the osseous tissuemust be broken down and removed. What term is used to define thebreaking down of osseous tissue (1 point)? Whichbone cell would be best suited for this task (1point)?

1. The extracellular matrix (ECM) of bone is considered to be acomposite material made up of organic and inorganic matter. Whatmakes up the organic and inorganic portions of the matrix(2 points)? Describe the cellular mechanisminvolved in breaking down this matrix; include the bone cellrequired for the process (2 points).