Question

A boy falls off his bike and skins his knee. In thinking about the structure of the lower leg and specifically the knee, it quickly becomes apparent that the knee is a good example of a location in the body where many types of tissues work together to perform a function – in this case movement. Identify at least four different types of tissues that are present in the lower leg and knee area. You must include at least 3 of the 4 categories (i.e. connective, epithelial, nervous, muscle) of the tissues you select. For each tissue you identify include the following information: name of tissue tissue category function of that tissue in the lower leg and knee region

Answer 1

The knee is a meeting place for four bones — the femur (thigh bone), tibia (shinbone), fibula (calf bone), and patella (kneecap). It requires several ligaments to keep these bones in place and maintain its ability to flex and bend.The knee joint capsule, also known as the articular capsule of the knee, is an important structural component.

Connective tissues found in knee joint:

Like many other joints in the body, the knee has a dense, fibrous, connective tissue that seals the joint space between the bones. In the knee, these bones are the femur and tibia. The patella sits outside the capsule. Inside this capsule are pads that cushion the joint. One of those pads is a bursa, a sac filled with a gelatinous liquid that helps prevent friction between bones in the joint. When the fluid becomes irritated or infected, it is known as bursitis, a condition that can make joint movement painful and stiff in the morning.

Also between the heads of the femur and tibia are the menisci. These are the medial meniscus and lateral meniscus. These are horseshoe-shaped pads of cartilage, a kind of strong, flexible tissue. They lie opposite each other on the inner (medial) and outer (lateral) edges of the tibia. They act as shock absorbers in the knee and help with weight distribution among the bones.

Ligaments are tough bands of fibrous tissue that connect bones. In the knee and other joints, they absorb pressure from twisting, impact, and other potentially harmful movements to ensure the bones stay in place. There are four ligaments in the knee. Two are located outside the knee joint capsule (Medial collateral ligament & Lateral collateral ligament) and two are located inside the knee joint capsule (Anterior cruciate ligament & posterior cruciate ligament).

Muscle tissues found in knee joint:

There are 2 groups of muscles involved in the knee, including the quadriceps muscles (located on the front of the thighs), which straighten the legs, and the hamstring muscles (located on the back of the thighs), which bend the leg at the knee.

Nervous tissues found in knee:

There are 3 major nerves found in knee join, the obturator, the femoral and the sciatic nerve. The obturator nerve supplies obturator externus, adductor brevis, and longus, and the anterior part of adductor magnus. The femoral nerve supplies iliacus, pectineus, all four heads of quadriceps, and sartorius. The sciatic nerve passes deep to biceps femoris. Above the knee, the sciatic nerve divides into two major nerves - the tibial nerve, and the common peroneal nerve.The tibial nerve runs downward in the midline, and passes between the two heads of gastrocnemius, along with the popliteal vessels. The common peroneal nerve diverges laterally, running just behind the tendon of biceps femoris.