Dissection Guide Dimensions Of Nursing

Anatomy and Physiology Dissection Gui Anatomy and Physiology Dissection Guide JOINT DISSECTION OF PIG A) Introduction to joint dissection of pig 1) Prior to knee dissection of the pig, please review the following anatomical structures and their functions within the knee: (a) Knee capsule (b) Patella (c) Patella tendon (d) Anterior collateral ligament (ACL), Posterior collateral ligament (PCL), Lateral collateral ligament (LCL) and medial collateral ligament (MCL) (e) Meniscus 2) Once you fully understand the anatomy and physiology of the above structures listed please continue with the knee dissection of the pig. B) Joint dissection of knee 1) Locate the knee joint of your pig specimen. Begin clearing the fascia, various connective tissue and muscle surrounding the knee. Locate the patella and the patella tendon. Refer to Figure 3.1 to assist your process of separating and identifying these structures. 2) Be careful and mindful not to puncture/cut the knee joint capsule or the medial and lateral collateral ligaments. 3) Once the patella tendon is identified, using your forceps, start looking for the medial and lateral collateral ligaments (MCL and LCL). They will be located medially and laterally respectively and will be a thin, narrow, tough band of white connective tissue connecting the femur to the tibia. 4) Refer to Figures 3.2 to assist your process of separating and identifying these ligaments. You may find two ligaments on the lateral side; pigs also have a fibula and there would be a ligament to connect the fibula to the femur too. 5) Once you have separated and identified the MCL and LCL, stress the knee joint laterally and medially by stabilizing the femur and tibia bones, then gently rock the tibia medially and laterally. Notice and observe the stability these ligaments provide to the knee joint with this movement. 6) Cut the LCL and re-stress the knee joint for lateral and medial movement. Notice and note the difference. Cut the MCL and re-stress the knee joint for lateral and medial movement. Notice and note the difference of movement. 7) Locate the patella and the patella tendon. Carefully cut the patella tendon at the distal end allowing the knee capsule to be exposed. Note the shape and texture of the inner surface of the patella and the groove found on the femur where the two articulate. Note any observations. 8) Once you located and identified the capsule, carefully make a small incision into the capsule being mindful of not to go to deep and cut the internal structures of the knee. Continue to the cut open the capsule around the knee to expose the internal knee. 9) As you expose the internal knee, you should identify the ACL, PCL and meniscus. You may have to remove some connective tissue to be able to clearly visually see these structures. Refer to Figure 3.4 to assist your process with identifying these structures; it demonstrates the LCL and MCL already cut. 10) Once you have separated and identified the ACL and PCL, stress the knee joint anteriorly and posteriorly by stabilizing the femur and tibia bones, then gently rock the tibia anteriorly and posteriorly. Notice and note the stability of the joint with these movements. 11) Cut the ACL first and re-stress the knee joint for anterior and posterior movement. Notice and note the change in movement. Cut the PCL next and re- stress the knee joint for anterior and posterior movement. Notice and note the change in movement. 12) With the internal knee exposed, identified the meniscus of the knee and note its location, shape and structure. Try to extract the meniscus from the knee and note any observations. Note how each meniscus is attached to the tibia and how its overall shape provides structural support to the femoral condyles. Refer to Figure 3.5 to assist your process of identifying the menisci of the knee. 13) If time permits, you may continue on to the hip joint dissection. On the same side that you completed the knee joint dissection, palpate for the hip joint on the pig; you may have to move the leg in order to locate the area of the hip joint. 14) Once located, carefully dissect and remove the muscular tissue surrounding the hip joint. It is advised to cut the muscle with the scalpel in a horizontal direction compared to vertical direction to preserve the articular capsule. Utilize the greater trochanter of the femur as a reference guide for your dissection. 15) Once the articular capsule is located, make an incision within it to expose the femoral head. Figure 3.6 demonstrates an incision within the articular capsule of the hip joint. Note the thickness of the capsular layers and the femoral head within the acetabulum. 16) Continue the incision within the articular capsule of the hip to demonstrate more of the femoral head within the acetabulum. The femoral head within the acetabulum is stabilized by the ligamentum teres (ligament of the head of the femur); this ligament spans from the femoral head to the acetabulum. As you pull up on the femoral head and try to dislocate it from the acetabulum, you will observe the ligamentum teres of the femur. Figure 3.7 demonstrates the ligamentum teres of the hip joint. 17) Once you have located the ligamentum teres, noted its thickness and stability it provides, cut it with your scissors or scalpel. Observe how the femoral head can be dislocated from the acetabulum and how deep the acetabulum is. Utilize figures 3.8 and 3.9 to assist in this process. 18) When you are finished with the dissection, make sure you cover the pig with its skin and place it back in its bag/container with the preserving fluid. Make sure each of your group members name is on the bag/container. Once the pig is stored appropriately, clean up your dissection kit materials and sterilize your tabletop.