![]() Thumb extension is carried out by abductor pollicis longus (APL), extensor pollicis brevis (EPB), and extensor pollicis longus (EPL). Thus, in various clinical pathologies that may cause a dynamic imbalance between the radial-based extensors (ECRL and ECRB) versus the ulnar-based extensor (ECU), wrist extension will occur with simultaneous and involuntary radial/ulnar deviation. To achieve neutral wrist extension movements, the extensor carpi radialis brevis (ECRB), extensor carpi radialis longus (ECRL), and the extensor carpi ulnaris (ECU) muscles act synergistically based on each muscle's insertion and dynamic function. For example, lateral epicondylitis affects 1-5% of the general population. Clinical pathology affecting one or multiple muscles in this group is not uncommon. These muscles generally originate on or near the lateral epicondyle and insert on the distal forearm or in the hand. To see the learning power of Complete Anatomy, try it for FREE today.The wrist extensor muscles comprise a significant component of the posterior forearm musculature. Use the power of 3D anatomy to better understand the muscle compartments of the anatomy. As it travels around the leg it envelops the external surface of the muscle compartments and blends with the periosteum overlying the tibia. Surrounding the entire leg is deep crural fascia. The transverse intermuscular septum indicates the division between deep and superficial muscles groups and the deep group is separated from the anterior compartment by the tibia, fibula, and the interosseous membrane running between them. Alongside these muscles are the posterior tibial artery and vein, the fibular artery and vein and the tibial nerve, which provides innervation to all of the muscles in the posterior compartment. ![]() Muscles in the deep posterior group are involved with flexion of the toes as well as stabilization of the knee and arch of the foot, and are called flexor digitorum longus, flexor hallucis longus, tibialis posterior and popliteus. The superficial group comprises three muscles which are the major contributors to plantar flexion – they are soleus, gastrocnemius, and plantaris. These muscles essentially lift the entire body weight on contraction. The muscles of the large posterior group are primarily responsible for plantar flexion of the foot, a movement that allows us to stand on our tippy toes and an essential part of gait. Dividing this muscle group from the anterior compartment is the anterior intermuscular septum, and separating it from the posterior compartment is the posterior intermuscular septum. ![]() These two muscles are fibularis longus and brevis, and their innervating nerve, the superficial fibular nerve. Within the lateral compartment are muscles that are primarily involved with eversion of the foot, to tilting the sole of the foot laterally. Also within this compartment is the anterior tibial artery and vein and the deep fibular nerve. They are tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius. The anterior compartment, also known as the extensor compartment, contains muscles that dorsiflex or extend the foot at the ankle joint, and muscles that flex the toes. The beefy posterior compartment is a major contributor to our mobility, specifically in walking and running, and is thus composed of large muscles – these muscles can be divided into deep and superficial groups. The anterior and lateral compartments occupy only a small portion of the muscular volume of the leg. As we said before, the leg is divided into three muscular compartments, however this can sometimes be classified as four muscle groups. For the final instalment of our examination of the muscular compartments let’s dive into the divisions of the leg.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |