The more body weight you have, the harder your trip will be. A whooping crane is one big bird. How does it manage to fly so far with all that "baggage" on board? Actually, a whooping crane is large but lightweight.
Like all birds, whooping cranes have hollow bones that make their bodies lighter. With hollow bones a bird can fly very long distances without getting worn out from carrying its own weight. Nevertheless, a definitive diagnosis requires X-ray examination to reveal the true nature and extent of the injury and how best to help the body repair the damage. A fracture requires emergency treatment.
Whether a fracture is simple or complex, closed or open, the goal of treatment is to assure reunion of the broken bone, stabilize motion between bone ends and fragments to promote healing, and restore normal length and alignment to affected limbs. Immediate first aid for a suspected fracture requires immobilizing and supporting the affected limb with a makeshift sling or splint. To limit swelling, the limb should be elevated with pillows to the same level as the heart.
Also apply ice to reduce pain and further control swelling. Restrict pain medication to acetaminophen, since anti-inflammatories ASA, ibuprofen and others impair blood clotting and could potentially worsen any internal bleeding. Call for emergency medical services to dispatch an ambulance.
Most fractures are closed and can be treated without surgery. In some cases, the doctor uses X-rays to guide the manipulation and a short period of traction using pulleys, ropes and weights may be required to gently pull the bone ends into place. If all goes well, usually the next step will be a splint or a cast to stabilize the fracture site. However, when X-rays reveal that closed reduction has not been achieved or that the fracture is complicated because of its type or location, the specialized skills of an orthopaedic surgeon are required.
One surgical approach to a difficult closed reduction or a reduction that is inherently unstable is to use external fixation, wherein the surgeon inserts long pins or screws through the skin and bone above and below the fracture. These are then secured on the outside of the skin with a system of clamps, rods and bars to create a frame around the fracture, pulling the bone ends together.
Once healing is complete, the device can be removed. Using special instruments to manipulate the fragments, the surgeon secures the fragments to the main body of bone, usually using some combination of metal wires, pins, screws, rods and metal plates.
Stainless steel, titanium rods, and other metal alloys can be inserted into the marrow cavity for structural support; contoured metal plates are fixed to the outside of the bone with screws to clamp together two large bone segments; and other fragments are stitched together with wire or nailed into place. Most open fractures are associated with car crashes or pedestrian injuries, industrial accidents and falls, and are best treated by a multi-disciplinary trauma team, since a patient will likely have other life-threatening injuries.
These types of fractures are clinically the most serious, since they involve an open wound that is frequently contaminated with dirt and debris, which could lead to infection. Additional complications include the extent of injury to soft tissues and blood vessels, and the complexity of the fracture pattern. For some people, blood loss is so great their blood pressure drops dangerously low, leading to systemic shock. If the wound is small, then it will be closed with sutures.
Wounds that are too large to close will eventually require plastic surgery; in the meantime, the wound is cleansed every two to three days in the OR until it has healed sufficiently to receive tissue grafts, usually after a week or so.
People are usually provided antibiotics prophylactically following an open fracture. If properly stabilized, even bone fragments reattach to the main body of bone. This takes place in three overlapping stages. First comes the inflammatory stage, where immune cells clean up the debris damaged cells, bone particles, blood clots from the fracture site. As the inflammatory stage reaches its peak in a day or two, the area around the fracture swells, stiffens, feels hot to the touch, and slight pressure causes acute pain.
Over several weeks, the inflammatory process slowly dies down. New tissue, called callus, begins to form between the bone ends several days after the fracture and then continues to grow for a month or more.
Initially, callus contains no calcium and is soft and pliable. This makes the new tissue vulnerable to tearing if the bone ends become displaced, which is why stabilization is so important. After three to six weeks, the callus hardens into calcified tissue and becomes structurally sound.
Callus is gradually replaced with harder, stronger bone, and any danger of a second disunion has usually passed. Bone formation is faster in children than adults.
A simple fracture may take four to six weeks to heal for a toddler, whereas a similar injury may take as many months in an adult. Ask students to compare the structure of the bone to the hollow and solid cylinders. Ask, Which cylinder does the bone most resemble? Help students to conclude that the relatively hollow design of real bones allows them to be light, but still strong enough to do their jobs. The thighbone femur is the longest bone in the body.
Its shaft is round in cross section. The main shinbone tibia is the second longest bone in the body. Its shaft is triangular in cross section. Challenge students to investigate the relative strengths of different-shaped columns.
Have students use note cards to create columns with different shapes in cross section round, square, triangular, etc. Ask them to consider the total amount of material necessary to build each kind of column as they reach their conclusions about relative strength. To observe how calcium contributes to the hardness of bones, have students soak cleaned chicken bones in vinegar for about one week.
Vinegar, a weak acid, will leach calcium out of the bones, which then will become weaker and softer. Students investigate bone and muscle structure, physical stress and nutrition, the body's center of gravity, and ways to prevent muscle and bone loss. What is Science? Slaptail's Curious Contraption Mr. Bone Structure: Hollow vs. Solid The hollow inside of a bird's ulna.
Teacher Background Objectives and Standards Materials and Setup Procedure and Extensions Handouts and Downloads Teacher Background Bones are living tissues that contain blood vessels and nerve cells within a structure composed of collagen a flexible fibrous material and minerals mainly calcium and phosphate. Objectives and Standards Concepts Long bones are made of hollow tubes, which give strength with minimal weight. Allow the bones to dry before using them in class. Place all materials in a central location.
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