Quadratus femoris muscle
Encyclopedia
The quadratus femoris is a flat, quadrilateral skeletal muscle
. Located on the posterior side of the hip joint, it is a strong external rotator
and adductor
of the thigh, but also acts to stabilize the femoral head
in the Acetabulum
.
. From there, it passes laterally to its insertion on the posterior side of the head of the femur: the quadrate tubercle
on the intertrochanteric crest
and along the quadrate line, the vertical line which runs downward to bisect the lesser trochanter
on the medial side of the femur. Along its course, quadratus is aligned edge to edge with the inferior gemellus
above and the adductor magnus
below, so that its upper and lower borders run horizontal and parallel.
At its origin, the upper margin of the adductor magnus is separated from it by the terminal branches of the medial femoral circumflex vessels.
A bursa
is often found between the front of this muscle and the lesser trochanter
. Sometimes absent.
Skeletal muscle
Skeletal muscle is a form of striated muscle tissue existing under control of the somatic nervous system- i.e. it is voluntarily controlled. It is one of three major muscle types, the others being cardiac and smooth muscle...
. Located on the posterior side of the hip joint, it is a strong external rotator
External rotation
External rotation is rotation away from the center of the body.The muscles of external rotation include:* of arm/humerus at shoulder** Deltoid muscle** Infraspinatus** Teres minor* of thigh/femur at hip ** Gluteus maximus...
and adductor
Adduction
Adduction is a movement which brings a part of the anatomy closer to the middle sagittal plane of the body. It is opposed to abduction.-Upper limb:* of arm at shoulder ** Subscapularis** Teres major** Pectoralis major** Infraspinatus...
of the thigh, but also acts to stabilize the femoral head
Femur head
The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...
in the Acetabulum
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
.
Course
It originates on the lateral border of the ischial tuberosity of the ischium of the pelvisPelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
. From there, it passes laterally to its insertion on the posterior side of the head of the femur: the quadrate tubercle
Tubercle of the femur
The quadrate tubercle is a small tubercle found upon the upper part of the femur.It is the point of insertion of the quadratus femoris....
on the intertrochanteric crest
Intertrochanteric crest
The intertrochanteric crest is a bony ridge located on the posterior side of the head of the femur, stretching obliquely downward and medially from the summit of the greater trochanter to the lesser trochanter....
and along the quadrate line, the vertical line which runs downward to bisect the lesser trochanter
Lesser trochanter
The lesser trochanter of the femur is a conical eminence, which varies in size in different subjects-Anatomy:It projects from the lower and back part of the base of the femur neck.From its apex three well-marked borders extend:...
on the medial side of the femur. Along its course, quadratus is aligned edge to edge with the inferior gemellus
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 which is received into a groove between them....
above and the adductor magnus
Adductor magnus muscle
The adductor magnus is a large triangular muscle, situated on the medial side of the thigh.It consists of two parts. The portion which arises from the ischiopubic ramus is called the "adductor portion", and the portion arising from the tuberosity of the ischium is called the "hamstring portion"...
below, so that its upper and lower borders run horizontal and parallel.
At its origin, the upper margin of the adductor magnus is separated from it by the terminal branches of the medial femoral circumflex vessels.
A bursa
Bursa (anatomy)
A bursa is a small fluid-filled sac lined by synovial membrane with an inner capillary layer of slimy fluid . It provides a cushion between bones and tendons and/or muscles around a joint. This helps to reduce friction between the bones and allows free movement...
is often found between the front of this muscle and the lesser trochanter
Lesser trochanter
The lesser trochanter of the femur is a conical eminence, which varies in size in different subjects-Anatomy:It projects from the lower and back part of the base of the femur neck.From its apex three well-marked borders extend:...
. Sometimes absent.