MSAK Knee And Ankle

The muscle that extends toes 2-5 is the extensor digitorum longus. This muscle is responsible for extending the second to fifth toes, allowing for movements such as pointing the toes or lifting them off the ground. The extensor hallucis longus is responsible for extending the big toe, while the flexor digitorum longus flexes the toes. The peroneus tertius is responsible for dorsiflexion and eversion of the foot. Therefore, the correct answer is extensor digitorum longus.

The correct answer is flexor digitorum longus because it is the muscle responsible for flexing the toes. The given information states that the muscle originates from the middle 1/3 of the posterior tibia and inserts into the distal phalanges of toes 2-5. Therefore, flexor digitorum longus is the most appropriate choice among the given options.

The correct answer is flexor hallucis longus because it is the muscle responsible for flexion of the first toe. The given information states that the action is flexion of the first toe, and the muscle that performs this action is the flexor hallucis longus.

The gastrocnemius muscle connects the medial and lateral condyles of the femur to the calcaneus via the Achilles tendon. This muscle plays a major role in plantar flexion of the foot and is responsible for the "calf" appearance in the lower leg.

The triceps surae is a group of muscles located in the calf region of the leg. These muscles work together to extend the foot and provide power for activities such as walking, running, and jumping. The gastrocnemius is the larger muscle of the two and is responsible for generating most of the force during these movements. The soleus, on the other hand, is a smaller muscle that lies underneath the gastrocnemius and helps to stabilize the ankle joint. Therefore, the correct answer is gastrocnemius and soleus.

The tibialis anterior is responsible for dorsiflexion, which is the movement that brings the foot towards the shin. The origin of the tibialis anterior is the proximal lateral tibia and interosseous membrane, and its insertion is on the 1st cuneiform and base of the 1st metatarsal. Therefore, the tibialis anterior is the correct answer as it matches the given information.

The normal range of motion (ROM) for ankle dorsiflexion is 20 degrees. This means that the ankle joint can be flexed upwards towards the shin by 20 degrees without any restriction or discomfort. Ankle dorsiflexion is important for activities such as walking, running, and climbing stairs. A ROM of 20 degrees allows for adequate movement and function of the ankle joint.

The popliteus muscle is known as "the key that unlocks the knee" because it plays a crucial role in unlocking the knee joint by initiating the rotation of the tibia bone. This muscle is located at the back of the knee and is responsible for initiating the movement that allows the knee to bend and unlock. Without the action of the popliteus muscle, the knee joint would remain locked, making it difficult to flex or extend the leg.

The correct answer is "fibularis brevis, longus, and tertius." The peroneus longus, brevis, and tertius muscles are also known as the fibularis longus, brevis, and tertius muscles. These muscles are located in the lateral compartment of the leg and are responsible for plantarflexion and eversion of the foot. They also play a role in stabilizing the ankle and foot during walking and running.

The popliteus muscle originates from the lateral epicondyle of the femur and inserts on the proximal posterior tibial shaft. It is responsible for unlocking the knee joint by internally rotating the tibia. This muscle is important for initiating knee flexion and is also involved in stabilizing the knee joint during weight-bearing activities.

The correct answer is extensor hallucis longus. This muscle originates from the middle anterior surface of the fibula and the interosseous membrane. It inserts into the distal phalanx of the 1st toe. Its action is to extend the 1st toe.

The correct answer is 50 because normal range of motion (ROM) for ankle plantar flexion is typically between 0 and 50 degrees. This means that the ankle joint can move from a neutral position (0 degrees) to a maximum of 50 degrees of plantar flexion, which is the movement of pointing the foot downwards. Therefore, 50 degrees is within the normal ROM for ankle plantar flexion.

The peroneus longus muscle originates from the proximal two-thirds of the lateral fibula and inserts into the first metatarsal and first cuneiform bones. This muscle is responsible for eversion of the foot and plantarflexion of the ankle.

The tibialis posterior muscle originates from the proximal 1/2 posterior shaft of the tibia, proximal fibula, and interosseous membrane. It inserts on all tarsals except the talus and the plantar surface of metatarsals 2-4. Therefore, the tibialis posterior muscle is responsible for flexing the toes, inverting the foot, and supporting the arch of the foot.

The extensor digitorum longus muscle is responsible for extending the toes 2-5. It originates from the proximal anterior shaft of the fibula and the interosseous membrane. Therefore, it matches the given origin and insertion points provided in the question.

The given numbers represent the range of motion (ROM) for ankle inversion. Ankle inversion refers to the movement of the ankle joint inwards, towards the midline of the body. A normal ROM for ankle inversion would typically be between 0 degrees (no movement) and 50 degrees. However, the number 90 is an outlier and does not fit within the expected range. Therefore, the correct answer is 5, which falls within the normal ROM range for ankle inversion.

The plantaris muscle connects the lateral condyle of the femur to the calcaneus via the Achilles tendon. The other muscles listed (gastrocnemius, tibialis posterior, and soleus) are also involved in the movement of the foot and ankle, but they do not specifically connect the lateral condyle of the femur to the calcaneus. Therefore, the correct answer is plantaris.

The peroneus longus is not a synergist muscle for inversion of the ankle. The muscles that contribute to ankle inversion are the flexor hallucis longus, extensor hallucis longus, and flexor digitorum longus. The peroneus longus, on the other hand, is responsible for eversion of the ankle, not inversion.

The popliteus muscle is not a superficial posterior leg muscle. The superficial posterior leg muscles include the soleus, gastrocnemius, and plantaris. The popliteus muscle is located deep within the leg, behind the knee joint, and is responsible for unlocking the knee by rotating the tibia.

Peroneus brevis is the correct answer because it originates from the distal 2/3 of the lateral fibula (O) and inserts at the base of the 5th metatarsal (I). Its action (A) is eversion.

The peroneus tertius is a muscle that originates from the distal 1/3 anterior fibula and interosseous membrane and inserts into the dorsal base of the 5th metatarsal. This muscle is responsible for dorsiflexion and eversion of the foot. It also assists in stabilizing the ankle joint during walking and running.

The soleus muscle originates from the posterior surface of the tibia and fibula and inserts into the calcaneus via the Achilles tendon. It is responsible for plantar flexion of the foot, which is the movement of pointing the toes downward. This muscle works in conjunction with other muscles such as the gastrocnemius, tibialis posterior, and plantaris to enable movements such as walking, running, and jumping.

The plantaris muscle is not an agonist muscle for plantar flexion. Plantar flexion is the movement of pointing the foot downwards, and the agonist muscles responsible for this movement are the soleus, tibialis posterior, and gastrocnemius. The plantaris muscle is a small muscle located behind the knee and assists in knee flexion and stabilization. Therefore, it is not involved in plantar flexion.

The correct answer is tibialis anterior and peroneus longus. These muscles are known collectively as the stirrup muscles because they help to maintain the arches of the foot and provide stability during walking and running. The tibialis anterior is located on the front of the lower leg and is responsible for dorsiflexion of the foot, while the peroneus longus is located on the outer side of the lower leg and is responsible for eversion and plantar flexion of the foot. Together, these muscles work to support the foot and ankle during movement.

The plantaris muscle acts as a synergist for plantar flexion. Synergist muscles assist the prime mover muscle in performing a specific movement. In this case, the prime mover muscle for plantar flexion is the gastrocnemius, which is responsible for pointing the foot downwards. The plantaris muscle, located behind the gastrocnemius, assists in this movement by contracting and adding extra force to the plantar flexion action. The tibialis anterior and soleus muscles are not directly involved in plantar flexion and therefore are not the correct answers.