Wilderness and Rescue Medicine 8th Edition

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Section IV: Trauma

femoral groove, making it impossible for the knee to function. Like the shoulder, the patella can dislocate with a direct blow or an indirect mechanism—typically a sudden extension of the knee while twisting or turning with the foot fixed in position by a cram- pon or ski. The patient often has a history of recur- rent dislocation. An indirect dislocation always leaves the patella pinned against the outside of the knee by the pull of the quadriceps (a lateral dislocation). The appearance can be deceiving. Shifting the patella laterally will make the end of the femur on the inside of the knee stand out and look like the missing patella. Like the shoulder, these dislocations are extremely uncomfortable and there is little or no active range of motion. Because the neurovascular bundle is not nearby, distal circulation and sen- sation are usually unaffected. Damage to other surrounding soft tissue will increase with time, as will the difficulty of reduction. Treatment of Patella Dislocation As with shoulder dislocation, a dislocated patella should be reduced if access to medical care will be delayed by more than two hours, or if the evacu- ation will be unreasonably difficult. Take the ten- sion off the structure by sitting the patient up to flex the hip. Then slowly straighten the knee. If the patella does not reduce on its own by the time the knee is in full extension, push it gently into place with your thumbs. Like the shoulder, relief of pain and return of mobility will indicate success. Also like the shoulder, these injuries are likely to result in swelling and significant pain later.

Scapular Manipulation

General Principles

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• Rotate the bottom of the scapula medially and the top laterally • Assistant applies traction to the arm or uses external rotation technique • Scapular

manipulation may be added to any other shoulder reduction technique

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Remember to check and document CSM both before and after reduction. Use a simple sling to splint the shoulder, adding a swathe if it makes the patient more comfortable. The patient should plan for medical follow-up within a week, if pos- sible. Pain-free activity is safe as long as the patient avoids abduction and external rotation. Some shoulders may remain quite painful immediately after reduction. This sometimes indicates that a small piece of bone is chipped from the head of the humerus. This should not be a cause for urgent evacuation if distal CSM (particularly circulation) is intact. Dislocations that result from direct force or are part of multiple trauma are more complicated and are best cared for in a medical facility with x-ray capabilities. Manipulation in the field is directed only at restoring CSM, if necessary and at positioning the patient for safe evacuation. If the patient is to be walked out, a sling with a swathe or pinned to the patient’s shirt or jacket is effective immobilization. If field reduction must be attempted, use the same techniques discussed above. Pain medication may be required. Patella Dislocation The patella is a sesamoid bone imbedded as a fulcrum in the quadriceps tendon. This large structure transmits the force of the contracting quadriceps muscle in the front of the thigh to the front of the lower leg to allow you to extend your knee. The tendon passes over a groove in the femur like a cable through a pulley. In patel- lar dislocation, the tendon and patella slip off the