Lateral rotator group
The lateral rotator group is a group of six small muscles of the hip which all externally rotate the femur in the hip joint. It consists of the following muscles: Piriformis, gemellus superior, obturator internus, gemellus inferior, quadratus femoris and the obturator externus. All muscles in the lateral rotator group originate from the hip bone and insert on to the upper extremity of the femur; the muscles are innervated by the sacral plexus, except the obturator externus muscle, innervated by the lumbar plexus. This group does not include all muscles which aid in lateral rotation of the hip joint: rather it is a collection of ones which are known for performing this action. Other muscles that contribute to lateral rotation of the hip include: Gluteus maximus muscle Gluteus medius muscle and gluteus minimus muscle when the hip is extended Psoas major muscle Psoas minor muscle Sartorius muscle Hip anatomy Glutealregion at The Anatomy Lesson by Wesley Norman
The obturator artery is a branch of the internal iliac artery that passes antero-inferiorly on the lateral wall of the pelvis, to the upper part of the obturator foramen, escaping from the pelvic cavity through the obturator canal, it divides into both an anterior and a posterior branch. In the pelvic cavity this vessel is in relation, with the obturator fascia. Inside the pelvis the obturator artery gives off iliac branches to the iliac fossa, which supply the bone and the Iliacus, anastomose with the ilio-lumbar artery; the pubic branch ascends upon the back of the pubis, communicating with the corresponding vessel of the opposite side, with the inferior epigastric artery. After passing through the obturator canal and outside of the pelvis, the obturator artery divides at the upper margin of the obturator foramen, into an anterior branch and a posterior branch of the obturator artery which encircle the foramen under cover of the obturator externus; the anterior branch of the obturator artery is a small artery in the thigh and runs forward on the outer surface of the obturator membrane and curves downward along the anterior margin of the obturator foramen.
It distributes branches to the obturator externus, pectineus and gracilis muscle, anastomoses with the posterior branch and with the medial femoral circumflex artery. The posterior branch of the obturator artery is a small artery in the thigh and follows the posterior margin of the foramen and turns forward on the inferior ramus of the ischium, where it anastomoses with the anterior branch, it gives twigs to the muscles attached to the ischial tuberosity and anastomoses with the inferior gluteal artery. It supplies an articular branch which enters the hip-joint through the acetabular notch, ramifies in the fat at the bottom of the acetabulum and sends a twig along the ligament of head of femur to the head of the femur; the blood supply to the femoral head and neck is enhanced by the artery of the ligamentum teres derived from the obturator artery. In adults, this is small and doesn't have much importance, but in children whose epiphyseal line is still made of cartilage, it helps to supply the head and neck of the femur on its own.
The articular branch is patent until 15 years of age. In adults it does not provide enough blood supply to prevent avascular necrosis in upper femur fractures; the obturator artery sometimes arises from the main stem or from the posterior trunk of the internal iliac artery, or it may arise from the superior gluteal artery. In about two out of every seven cases it arises from the inferior epigastric and descends vertically to the upper part of the obturator foramen; the artery in this course lies in contact with the external iliac vein, on the lateral side of the femoral ring. It can pass medial to the femoral ring along the margin of the lacunar ligament. In either case it would be at risk of injury during the operation to repair a femoral hernia, whether the hernia is reducible, incarcerated or strangulated; when the obturator artery travels along the lacunar ligament, it nearly encircles the femoral ring and can be lacerated during a femoral hernia repair. Most femoral hernias are repaired through a small incision in the groin area, rather than through the abdomen, so if a laceration were to occur, bleeding may not be recognized and result in significant blood loss into the peritoneal cavity.
Because of this danger, the anatomic variant in Figure B is sometimes referred to as the "crown of death". This article incorporates text in the public domain from page 616 of the 20th edition of Gray's Anatomy Anatomy photo:43:13-0201 at the SUNY Downstate Medical Center - "The Female Pelvis: Branches of Internal Iliac Artery" pelvis at The Anatomy Lesson by Wesley Norman MedEd at Loyola Grossanatomy/dissector/practical/pelvis/pelvis15.html Variations at anatomyatlases.org Variations at anatomyatlases.org
Articularis genus muscle
The articularis genus is a small skeletal muscle located anteriorly on the thigh just above the knee. It arises from the anterior surface of the lower part of the body of the femur, deep to the vastus intermedius, close to the knee and from the deep fibers of the vastus intermedius, its insertion is on the synovial membrane of the knee-joint. It is supplied by the lateral femoral circumflex artery, it is innervated by branches of the femoral nerve. Flat and variable, sometimes consisting of several separate muscular bundles, this muscle is without a distinct investing fascia and ranges 1.5–3 cm in width. It is distinct from the vastus intermedius, but blended with it. Articularis genus pulls the suprapatellar bursa superiorly during extension of the knee, prevents impingement of the synovial membrane between the patella and the femur; this article incorporates text in the public domain from page 471 of the 20th edition of Gray's Anatomy Farshchian's Orthopedic Regenerative Series: The Knee.
The gluteal muscles are a group of three muscles which make up the buttocks: the gluteus maximus, gluteus medius and gluteus minimus. The three muscles insert on the femur; the functions of the muscles include extension, external rotation and internal rotation of the hip joint. The gluteus maximus is the most superficial of the three gluteal muscles, it makes up a large portion of the appearance of the hips. It is a narrow and thick fleshy mass of a quadrilateral shape, forms the prominence of the nates; the gluteus medius is a broad, radiating muscle, situated on the outer surface of the pelvis. It lies profound to the gluteus maximus and 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 minimus is the smallest of the three gluteal muscles and is situated beneath the gluteus medius. The bulk of the gluteal muscle mass contributes only to shape of the buttocks; the other major contributing factor is that of the panniculus adiposus of the buttocks, well developed in this area, gives the buttock its characteristic rounded shape.
The gluteal muscle bulk and tone can be improved with exercise. However, it is predominantly the disposition of the overlying panniculus adiposus which may cause sagging in this region of the body. Exercise in general which can contribute to fat loss can lead to reduction of mass in subcutaneal fat storage locations on the body which includes the panniculus, so for leaner and more active individuals, the glutes will more predominantly contribute to the shape than someone less active with a fattier composition; the degree of body fat stored in various locations such as the panniculus is dictated by genetic and hormonal profiles. The gluteus maximus arises from the posterior gluteal line of the inner upper ilium, the rough portion of bone including the crest above and behind it; the fibers are lateralward. Its action is to extend and to laterally rotate the hip, to extend the trunk; the gluteus medius muscle 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; the gluteus minimus is fan-shaped, arising from the outer surface of the ilium, between the anterior and inferior gluteal lines, behind, from the margin of the greater sciatic notch. The fibers converge to the deep surface of a radiated aponeurosis, this ends in a tendon, inserted into an impression on the anterior border of the greater trochanter, gives an expansion to the capsule of the hip joint; the functions of muscles includes extension, lateral rotation and medial rotation of the hip joint. The gluteus maximus supports the extended knee through the iliotibial tract. Sitting for long periods can lead to the gluteal muscles atrophying through constant pressure and disuse; this may be associated with lower back pain, difficulty with some movements that require the gluteal muscles, such as rising from the seated position, climbing stairs.
Any exercise that works and/or stretches the buttocks is suitable, for example lunges, hip thrusts, climbing stairs, bicycling, squats, arabesque and various specific exercises for the bottom. Weight training exercises which are known to strengthen the gluteal muscles include the squat, leg press, any other movements involving external hip rotation and hip extension. Gluteal crease McMinn, RMH Last applied. London: Churchill Livingstone. ISBN 0-443-04662-X 8b; the Muscles and Fasciæ of the Thigh Bartleby.com, Henry Gray, Anatomy of the Human Body, 1918
The vastus medialis is an extensor muscle located medially in the thigh that extends the knee. The vastus medialis is part of the quadriceps muscle group; the vastus medialis is a muscle present in the anterior compartment of thigh, is one of the four muscles that make up the quadriceps muscle. The others are vastus intermedius and rectus femoris, it is the most medial of the "vastus" group of muscles. The vastus medialis arises medially along the entire length of the femur, attaches with the other muscles of the quadriceps in the quadriceps tendon; the vastus medialis muscle originates from a continuous line of attachment on the femur, which begins on the front and middle side on the intertrochanteric line of the femur. It continues down and back along the pectineal line and descends along the inner lip of the linea aspera and onto the medial supracondylar line of the femur; the fibers converge onto the inner part of the quadriceps tendon and the inner border of the patella. The obliquus genus muscle is the most distal segment of the vastus medialis muscle.
Its specific training plays an important role in maintaining patella position and limiting injuries to the knee. With no clear delineation, it is the most distal group of fibers of the vastus medialis; the vastus medialis is one of four muscles in the anterior compartment of the thigh. It is involved in knee extension, along with the other muscles the quadriceps muscle; the vastus medialis contributes to correct tracking of the patella. A division of the vastus medialis muscle into two groups of fibers has been hypothesized, a long and inline group of fibres with the quadriceps ligament, the vastus medialis longus. There is as yet insufficient evidence to conclusively deny this hypothesis. Knee pain is thought to be associated with specific quadriceps muscle weakness or fatigue in the vastus medialis obliquus, it is known that fatigue can be caused by many different mechanisms, ranging from the accumulation of metabolites within muscle fibers to the generation of an inadequate motor command in the motor cortex.
Characteristics of the vastus medialis, including its angle of insertion, correlate with presence of knee joint pain. However, this syndrome is complex and definitive evidence of causality has not yet been published. Misfiring and fatiguing of the VMO causes mal-tracking of the patella and subsequent damage to surrounding structures creating increased force on the knees resulting in injuries such as patellofemoral pain syndrome, anterior cruciate ligament rupture and tendinitis. Through the use of electromyography, researchers can evaluate and record the electrical activity produced by the skeletal muscle of the VMO to analyze the biomechanics and detect any possible abnormalities, weakness, or fatigue. With an analysis of muscle activity of the VMO through the use of electromyography, proper rehabilitative plans and goals can be established to not only correct the established abnormality, but prevent such injuries if tested sooner. Preventing injuries is crucial as well as teaching proper training techniques to ensure there are no valgus collapse forces causing unplanned stress on other structures of the knee, causing asymmetry, predisposing that individual for injury.
Medial patellofemoral ligament This article incorporates text in the public domain from page 471 of the 20th edition of Gray's Anatomy Cross section image: pembody/body18b—Plastination Laboratory at the Medical University of Vienna PTCentral
Adductor longus muscle
In the human body, the adductor longus is a skeletal muscle located in the thigh. One of the adductor muscles of the hip, its main function is to adduct the thigh and it is innervated by the obturator nerve, it forms the medial wall of the femoral triangle. The adductor longus arises from the superior ramus of the pubis, it lies ventrally on the adductor magnus, near the femur, the adductor brevis is interposed between these two muscles. Distally, the fibers of the adductor longus extend into the adductor canal, it is inserted into the middle third of the medial lip of the linea aspera. The adductor longus is in relation by its anterior surface with the pubic portion of the fascia lata, near its insertion with the femoral artery and vein. By its posterior surface with the adductor brevis and magnus, the anterior branches of the obturator artery and nerves, near its insertion with the profunda artery and vein. By its outer border with the pectineus, by the inner border with the gracilis, its main actions is to laterally rotate the thigh.
As part of the medial compartment of the thigh, the adductor longus is innervated by the anterior division of the obturator nerve. The obturator nerve exits via the anterior rami of the spinal cord from L2, L3, L4. Adductor longus is derived from the myotome of spinal roots L2, L3, L4. Cross section image: pembody/body18b—Plastination Laboratory at the Medical University of Vienna Cross section image: pelvis/pelvis-e12-15—Plastination Laboratory at the Medical University of Vienna PTCentral
External obturator muscle
The external obturator muscle, obturator externus muscle is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis. It is sometimes considered part of the medial compartment of thigh, sometimes considered part of the gluteal region, it arises from the margin of bone around the medial side of the obturator membrane and surrounding bone, viz. from the inferior pubic ramus, the ramus of the ischium. The fibers springing from the pubic arch extend on to the inner surface of the bone, where they obtain a narrow origin between the margin of the foramen and the attachment of the obturator membrane; the fibers converge and pass posterolateral and upward, end in a tendon which runs across the back of the neck of the femur and lower part of the capsule of the hip joint and is inserted into the trochanteric fossa of the femur. The obturator vessels lie between the obturator membrane. In 33 % of people a supernumerary muscle is found between the adductor minimus. While this muscle, when present, is similar to its neighbouring adductors, it is formed by separation from the superficial layer of the external obturator, is thus not ontogenetically related to the adductor muscles of the hip.
This muscle originates from the upper part of the inferior pubic ramus from where it runs downwards and laterally. In half of cases, it inserts into the anterior surface of the insertion aponeurosis of the adductor minimus. In the remaining cases, it is either inserted into the upper part of the pectineal line or the posterior part of the lesser trochanter, it has been demonstrated by the course of the posterior branch of obturator nerve that the obturator externus is divided into a superior muscle fascicle and a main belly. The supernumerary muscle described above originates from the superior fascicle, while an anomalous fascicle — derived from the external obturator — originates from the main belly; the "original" external obturator, i.e. without these supernumerary muscular parts occurs in only 20% of cases, the external obturator undergoes ontogenetic variations. The external obturator muscle acts as the lateral rotator of the hip joint; as a short muscle around the hip joint, it stabilizes the hip joint as a postural muscle.
This article incorporates text in the public domain from page 477 of the 20th edition of Gray's Anatomy Cross section image: pelvis/pelvis-e12-15—Plastination Laboratory at the Medical University of Vienna lljoints at The Anatomy Lesson by Wesley Norman PTCentral