The gracilis muscle (; Latin for "slender") is the most superficial muscle on the
medial
Medial may refer to:
Mathematics
* Medial magma, a mathematical identity in algebra Geometry
* Medial axis, in geometry the set of all points having more than one closest point on an object's boundary
* Medial graph, another graph that re ...
side of the
thigh. It is thin and flattened, broad above, narrow and tapering below.
Structure
It arises by a thin
aponeurosis from the anterior margins of the lower half of the
symphysis pubis
The pubic symphysis is a secondary cartilaginous joint between the left and right superior pubic ramus, superior rami of the pubis of the pubis (bone), hip bones. It is in front of and below the urinary bladder. In males, the suspensory ligament o ...
and the upper half of the
pubic arch.
The muscle's fibers run vertically downward, ending in a rounded tendon. This tendon passes behind the
medial condyle of the
femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates wit ...
, curves around the
medial condyle of the tibia
The medial condyle is the medial (or inner) portion of the upper extremity of tibia.
It is the site of insertion for the semimembranosus muscle
The semimembranosus muscle () is the most medial of the three hamstring muscles in the thigh. It i ...
where it becomes flattened, and inserts into the upper part of the medial surface of the body of the
tibia, below the condyle. For this reason, the muscle is a lower limb
adductor. At its insertion the tendon is situated immediately above that of the
semitendinosus muscle, and its upper edge is overlapped by the tendon of the
sartorius muscle, which it joins to form the
pes anserinus. The pes anserinus is separated from the
medial collateral ligament of the
knee-joint by a
bursa
( grc-gre, Προῦσα, Proûsa, Latin: Prusa, ota, بورسه, Arabic:بورصة) is a city in northwestern Turkey and the administrative center of Bursa Province. The fourth-most populous city in Turkey and second-most populous in t ...
.
A few of the fibers of the lower part of the tendon are prolonged into the deep fascia of the leg.
Relations
By its inner or superficial surface gracilis is in relation with the
fascia lata, and below with the
sartorius and internal
saphenous nerve; the internal
saphenous vein crosses it lying superficially to the fascia lata.
By its outer or deep surface with the
adductor longus,
brevis, and
magnus, and the internal lateral ligament of the knee-joint, from which it is separated by a synovial bursa common to the tendons of the gracilis and
semitendinosus.
Nerve supply
The obturator nerve innervates the gracilis muscle via the lumbar spinal vertebrae.
Function
The muscle adducts, medially rotates (with hip flexion), laterally rotates, and
flexes
Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relative ...
the hip as above, and also aids in flexion of the knee.
Clinical significance
The gracilis muscle is commonly used as a
flap in
microsurgery
Microsurgery is a general term for surgery requiring an operating microscope. The most obvious developments have been procedures developed to allow anastomosis of successively smaller blood vessels and nerves (typically 1 mm in diameter) wh ...
. According to the classification of Mathes and Nahai, it presents a type II blood supply, allowing it to be transferred on its artery derived from the medial circumflex femoral artery. This artery enters the muscle about 10 cm from the pubic symphysis. At this point (or 1 cm proximal) the nerve also enters.
Gracilis muscle is widely used in reconstructive surgery (graciloplasty), either as a pedicled flap or as a free microsurgical flap. Both pedicled and free flaps can be muscular or musculocutaneous (the so- called "composite flaps"). As a pedicled flap, gracilis muscle can be used in perineal and vaginal reconstruction, after oncological surgery, in the treatment of recurrent anovaginal and rectovaginal fistulas as well in the coverage of the neurovascular bundle after vascular surgery.
As a functioning pedicled flap, the gracilis muscle can be transferred for the treatment of anal incontinence. This technique called graciloplasty was described in the 1950s by Pickrell and was revolutionized in the late 1980s by the introduction of chronic muscle electro-stimulation. The gracilis microsurgical free flap is commonly used in the reconstruction of upper and lower limbs, in breast reconstruction and – as a free functioning flap – to restore forearm function or in dynamic reconstruction of facial paralysis.
Transplantation sites
The muscle may be split to reduce bulk for
facial reanimation
A facial is a family of skin care treatments for the face, including steam, exfoliation (physical and chemical), extraction, creams, lotions, facial masks, peels, and massage. They are normally performed in beauty salons, but are also a comm ...
, as well as to repair hand muscles. It can be used to fashion an
external anal sphincter.
Additional images
File:Gray235.png, Right hip bone. External surface.
File:Gray344.png, Structures surrounding right hip-joint.
File:Gray430.png, Muscles of the iliac and anterior femoral regions.
File:Gray434.png, Muscles of the gluteal and posterior femoral regions.
File:Gray549.png, The left femoral triangle.
File:Gray827.png, Nerves of the right lower extremity. Front view.
File:Anatomical dissection6.JPG, Gracilis muscle
File:Slide3rrr.JPG, Gracilis muscle
File:Slide3www.JPG, Gracilis muscle
File:Slide8CCCC.JPG, Gracilis muscle
File:Slide4FFFFF.JPG, Gracilis muscle
File:Slide6LLLL.JPG, Gracilis muscle
File:Slide3WWWW.JPG, Gracilis muscle
File:Slide11WWWW.JPG, Gracilis muscle
File:Slide2DADE.JPG, Muscles of thigh. Lateral view.
File:Slide2EA.JPG, Muscles of thigh. Cross section.
See also
Gracilis Muscles Clinical Role
References
External links
* - "Muscles of the anterior (extensor) compartment of the
thigh."
* - "Muscles that form the superficial boundaries of the
popliteal fossa."
*
{{DEFAULTSORT:Gracilis Muscle
Hip adductors
Hip flexors
Thigh muscles
Medial compartment of thigh