Inferior gemellus muscle
The inferior gemellus muscle is a muscle of the human body. The Gemelli are two small muscular fasciculi, accessories to the tendon of the Obturator internus, received into a groove between them; the Gemellus inferior arises from the upper part of the tuberosity of the ischium below the groove for the Obturator internus tendon. It blends with the lower part of the tendon of the Obturator internus, is inserted with it into the medial surface of the greater trochanter. Absent. Like the obturator internus muscle, the gemellus superior and gemellus inferior help to steady the femoral head in the acetabulum. Both muscles help to laterally rotate the extended thigh and abduct the flexed thigh at the hip Superior gemellus muscle This article incorporates text in the public domain from page 477 of the 20th edition of Gray's Anatomy PTCentral Anatomy photo:13:st-0401 at the SUNY Downstate Medical Center
The gluteus medius one of the three gluteal muscles, is a broad, radiating muscle, situated on the outer surface of the pelvis. Its posterior third is covered by the gluteus maximus, its anterior two-thirds by the gluteal aponeurosis, which separates it from the superficial fascia and integument; the gluteus medius muscle starts, or "originates," on the outer surface of the ilium between the iliac crest and the posterior gluteal line above, the anterior gluteal line below. The fibers of the muscle converge into a strong flattened tendon that inserts on the lateral surface of the greater trochanter. More the muscle's tendon inserts into an oblique ridge that runs downward and forward on the lateral surface of the greater trochanter. A bursa separates the tendon of the muscle from the surface of the trochanter; the posterior border may be more or less united to the piriformis, or some of the fibers end on its tendon. The posterior fibres of gluteus medius contract to produce hip extension, lateral rotation and abduction.
During gait, the posterior fibres help to decelerate internal rotation of the femur at the end of swing phase. • The anterior part acting alone helps to flex and internally rotate the hip. • The posterior part acting alone helps to extend and externally rotate the hip. • The anterior and posterior parts working together abduct the hip and stabilize the pelvis in the coronal plane. Dysfunction of the gluteus medius or the superior gluteal nerve can be indicated by a positive Trendelenburg's sign. Trendelenburg gait This article incorporates text in the public domain from page 474 of the 20th edition of Gray's Anatomy Anatomy photo:13:st-0404 at the SUNY Downstate Medical Center Cross section image: pelvis/pelvis-e12-15—Plastination Laboratory at the Medical University of Vienna
Extensor digitorum longus muscle
The extensor digitorum longus is a pennate muscle, situated at the lateral part of the front of the leg. It arises from the lateral condyle of the tibia. Between it and the tibialis anterior are the upper portions of the anterior tibial vessels and deep peroneal nerve; the muscle passes under the superior and inferior extensor retinaculum of foot in company with the fibularis tertius, divides into four slips, which run forward on the dorsum of the foot, are inserted into the second and third phalanges of the four lesser toes. The tendons to the second and fourth toes are each joined, opposite the metatarsophalangeal articulations, on the lateral side by a tendon of the extensor digitorum brevis; the tendons are inserted in the following manner: each receives a fibrous expansion from the interossei and lumbricals, spreads out into a broad aponeurosis, which covers the dorsal surface of the first phalanx: this aponeurosis, at the articulation of the first with the second phalanx, divides into three slips—an intermediate, inserted into the base of the second phalanx.
This muscle varies in the modes of origin and the arrangement of its various tendons. The tendons to the second and fifth toes may be found doubled, or extra slips are given off from one or more tendons to their corresponding metatarsal bones, or to the short extensor, or to one of the interosseous muscles. A slip to the great toe from the innermost tendon has been found. Extensor digitorum brevis muscle Extensor digitorum muscle This article incorporates text in the public domain from page 481 of the 20th edition of Gray's Anatomy Anatomy photo:15:st-0401 at the SUNY Downstate Medical Center PTCentral
Flexor hallucis longus muscle
The flexor hallucis longus muscle is one of the three deep muscles of the posterior compartment of the leg that attaches to the plantar surface of the distal phalanx of the great toe. The other deep muscles are the flexor digitorum tibialis posterior. All three muscles are innervated by the tibial nerve; the flexor hallucis. It arises from the inferior two-thirds of the posterior surface of the body of the fibula, with the exception of 2.5 cm. at its lowest part. The fibers pass obliquely downward and backward, where it passes through the tarsal tunnel on the medial side of the foot and end in a tendon which occupies nearly the whole length of the posterior surface of the muscle; this tendon lies in a groove which crosses the posterior surface of the lower end of the tibia, between the medial and lateral tubercles of the posterior surface of the talus, the under surface of the sustentaculum tali of the calcaneus. The grooves on the talus and calcaneus, which contain the tendon of the muscle, are converted by tendinous fibers into distinct canals, lined by a mucous sheath.
As the tendon passes forward in the sole of the foot, it is situated above, crosses from the lateral to the medial side of the tendon of the flexor digitorum longus, to which it is connected by a fibrous slip. A slip runs to the flexor digitorum and an additional slip runs from the flexor digitorum to the flexor hallucis. Peroneocalcaneus internus, arises below or outside the flexor hallucis from the back of the fibula, passes over the sustentaculum tali with the flexor hallucis and inserts into the calcaneum. Similar to the flexor digitorum longus and tibialis posterior muscles, the flexor hallucis longus muscle functions to plantar flex and invert the foot. However, it is unique in that it functions to flex the great toe and helps supinate the ankle. Common injuries associated with the FHL tendon are tenosynovitis and muscle strains; because the FHL muscle is small, injuries associated with this muscle and its tendon are overlooked. An MRI can be used to evaluate the condition of the FHL tendon.
Tears and areas of impingement can be found using this method. A diagnostic ultrasound can be used to diagnose FHL injuries, as it shows the muscle in movement and potential areas of impingement. Conservatively, an FHL injury can be evaluated by determining if movements caused by the FHL muscle cause pain along the inner ankle or under the big toe. After passing through the tarsal tunnel, the flexor hallucis longus tendon must curve around a bony landmark called the sustenaculum tali. Friction at this site is to cause pain on the posteromedial aspect of the ankle. While referred to as "dancer's tendinitis," FHL tendinitis occurs in ballet dancers and runners. Due to their excessive use of toe flexion, which results in ten times their body weight being applied to this small muscle and tendon and irritation is common at the site of the sustenaculum tali. Hallux saltans is a condition. With this condition, a nodule develops along the FHL tendon which may produce a popping effect during contraction because it drags along surrounding tissues.
If left untreated and continually irritated, stenosis of the tendon may occur, resulting in the big toe becoming stiff and immobile. This condition is known as Hallux Rigidus. Most FHL injuries can be managed through conservative treatment. Rest is the first indicated intervention for minor FHL injuries. Ice and ultrasound therapy can help with the inflammation and pain. Physical therapy exercises and stretches can help rehabilitate the muscle and tendon and address biomechanical errors that cause the inflammation and microtears in the tendon; some FHL injuries can be treated through rest, physical therapy and anti-inflammatory medication. However, more serious or chronic injuries may require surgery. If surgery is indicated, tears in the FHL will be repaired, debris will be removed from the area, it is worth noting that an os trigonum may cause similar symptoms to the ones caused by FHL tendinitis or tenosynovitis. A radiograph should be taken to rule out this condition; this article incorporates text in the public domain from page 485 of the 20th edition of Gray's Anatomy Anatomy photo:15:st-0404 at the SUNY Downstate Medical Center PTCentral
Anterior compartment of thigh
The anterior compartment of thigh contains muscles which extend the knee and flex the hip. The anterior compartment is one of the fascial compartments of the thigh that contains groups of muscles together with their nerves and blood supply; the anterior compartment contains the sartorius muscle and the quadriceps femoris group, which consists of the rectus femoris muscle and the three vasti muscles – the vastus lateralis, vastus intermedius, the vastus medialis. The iliopsoas is sometimes considered a member of the anterior compartment muscles, as is the articularis genus muscle; the anterior compartment is separated from the posterior compartment by the lateral intermuscular septum and from the medial compartment by the medial intermuscular septum. The nerve of the anterior compartment of thigh is the femoral nerve. Innervation for the quadriceps muscles come from the posterior division of the femoral nerve, while the anterior division gives a lateral and a medial branch, the second being responsible for the innervation of the sartorius muscle.
The iliacus and the psoas major and psoas minor muscles, sometimes considered part of the anterior compartment, do not share the same innervation. Whereas the iliacus is innervated by the femoral nerve, the psoas is innervated by ventral rami of L1-L3; when the external iliac artery crosses the inguinal ligament, it becomes the femoral artery, which supplies blood to the anterior compartment and is the largest blood vessel of the inferior member. The anterior compartment of thigh contains muscles which are extensors of the knee and flexors of the hip joints; the anterior compartment may be affected as part of a compartment syndrome. Antthigh at The Anatomy Lesson by Wesley Norman knee/muscles/thigh1 at the Dartmouth Medical School's Department of Anatomy Overview at stanford.edu
The semimembranosus is the most medial of the three hamstring muscles. It is so named, it lies posteromedially in the thigh, deep to the semitendinosus. The semimembranosus, so called from its membranous tendon of origin, is situated at the back and medial side of the thigh, its origin is the superolateral aspect of the ischial tuberosity and it inserts on the medial condyle and nearby margin of tibia. It arises by a thick tendon from the upper and outer impression on the ischial tuberosity and medial to the biceps femoris and semitendinosus; the tendon of origin expands into an aponeurosis, which covers the upper part of the anterior surface of the muscle. It is inserted into the horizontal groove on the posterior medial aspect of the medial condyle of the tibia; the semimembranosus is wider and deeper than the semitendinosus. The tendon of insertion gives off certain fibrous expansions: one, of considerable size, passes upward and laterally to be inserted into the posterior lateral condyle of the femur, forming part of the oblique popliteal ligament of the knee-joint.
The muscle overlaps the upper part of the popliteal vessels. The semimembranosus is innervated by the tibial part of the sciatic nerve; the sciatic nerve consists of the anterior divisions of ventral nerve roots from L4 through S3. These nerve roots are part of the larger nerve network–the sacral plexus; the tibial part of the sciatic nerve is responsible for innervation of semitendinosus and the long head of biceps femoris. It may be reduced or absent, or double, arising from the sacrotuberous ligament and giving a slip to the femur or adductor magnus; the semimembranosus helps to flex the knee joint. It helps to medially rotate the knee: the tibia medially rotates on the femur when the knee is flexed, it medially rotates the femur. The muscle can aid in counteracting the forward bending at the hip joint. Semitendinosus Biceps femoris This article incorporates text in the public domain from page 479 of the 20th edition of Gray's Anatomy Anatomy photo:14:st-0408 at the SUNY Downstate Medical Center Anatomy figure: 14:01-07 at Human Anatomy Online, SUNY Downstate Medical Center - "Muscles of the posterior compartment of the thigh."
Anatomy figure: 14:02-06 at Human Anatomy Online, SUNY Downstate Medical Center - "Muscles that form the superficial boundaries of the popliteal fossa." Knee/surface/surface4 at the Dartmouth Medical School's Department of Anatomy PTCentral
The deltoid ligament is a strong, triangular band, above, to the apex and anterior and posterior borders of the medial malleolus. The deltoid ligament is composed of: 1. Anterior tibiotalar ligament 2. Tibiocalcaneal ligament 3. Posterior tibiotalar ligament 4. Tibionavicular ligament, it consists of two sets of fibers and deep. Of the superficial fibres, tibionavicular pass forward to be inserted into the tuberosity of the navicular bone, behind this they blend with the medial margin of the plantar calcaneonavicular ligament; this article incorporates text in the public domain from page 350 of the 20th edition of Gray's Anatomy Deltoid_ligament at the Duke University Health System's Orthopedics program lljoints at The Anatomy Lesson by Wesley Norman http://www.ithaca.edu/faculty/lahr/LE2000/ankle%20pics/5medankle-new.jpg Thompson, Jon C. Netter's concise atlas of orthopaedic anatomy. Icon Learning Systems, 2002. 349-351