What is the biceps femoris?
Biceps femoris is a long muscle of the posterior aspect of the thigh. Together with the semitendinosus and semimembranosus muscles, it makes the group of muscles commonly known as the hamstrings . Biceps femoris muscle runs from the ischial tuberosity, all the way to the proximal part of the fibula.
What is the aponeurotic sheet of the biceps femoris?
Near the muscle’s insertion, the long head of biceps femoris continues as an aponeurosis. The muscle fibers from the short head join the aponeurotic sheet, comprising the round common tendon that inserts to the lateral aspect of the head of the fibula.
Where do the tendons of the biceps femoris and semitendinosus run together?
The tendons of biceps femoris and semitendinosus run together for a distance before separating into two distinct muscles. The short head originates quite distally from the long head, arising from the lateral lip of the inferior third of the linea aspera and supracondylar ridge of femur.
What nerve innervates the biceps femoris?
Innervation. The biceps femoris muscle is supplied by the terminal branches of the sciatic nerve. The long head receives innervation from it’s tibial division, while the short is innervated by the common fibular division. Both the tibial and common fibular divisions have the same root values (spinal nerves L5, S1 and S2).
Is the biceps femoris an antagonist to the rectus femoris?
Answer and Explanation: There are multiple antagonists to the biceps femoris. The most correct answer would be the rectus femoris because it also has actions at the hip and...
Which muscles are antagonists?
Examples of Antagonistic MusclesBiceps and triceps.Gluteus maximum and hip flexors.Hamstrings and quadriceps.Pectoralis major and latissimus dorsi.Gastrocnemius and tibialis anterior.Abductor and adductor.
Which muscle is a synergist to the biceps femoris?
Synergist: Prime Movers: Gluteus maximus, Adductor magnus (posterior part).
What is the antagonist to the biceps brachii?
In this example, biceps brachii is the agonist or prime mover. Triceps brachii is the antagonist and brachialis is a synergist with biceps brachii.
What are examples of antagonists?
Antagonist ExamplesDarth Vadar is the main antagonist of Luke Skywalker in Star Wars.Mr. ... The wolf is the antagonist in "The Three Little Pigs."MacDuff is an antagonist of Macbeth in Macbeth.In Dr. ... In the movie Aladdin, Jafar is the antagonist.More items...
Are hamstrings antagonist?
In this scenario, our hamstring is the agonist muscle (in that it's contracted, and applying the necessary force to move the knee) and the quadriceps are the antagonist muscle (these are relaxed, and offer a counterbalance for the force that the agonist muscle is applying).
What is the antagonist of the rectus femoris?
The hamstrings are the antagonist muscles to the rectus femoris. That means they produce the opposite action.
What are synergist and antagonist muscles?
Following contraction, the antagonist muscle paired to the agonist muscle returns the limb to the previous position. Synergist muscles act around a movable joint to produce motion similar to or in concert with agonist muscles, allowing for a range of possible movements.
In what movements are the biceps femoris and the semitendinosus antagonists?
Antagonists to flexion at the hip include the gluteus maximus, the hamstrings (specifically the long head of biceps femoris), and the semimembranosus and semitendinosus, which all act to extend at the hip.
What is the antagonist muscle in a bicep curl?
During a biceps curl, the opposing muscle group—the antagonist—is the triceps.
Is triceps brachii antagonist?
The triceps is the antagonist because it is on the opposite side of the elbow joint and has the potential to oppose the elbow flexion. Now, if we are talking about active elbow extension, the triceps is the agonist because it causes the action, and the biceps is the antagonist.
Which muscle is an antagonist to the biceps brachii muscle quizlet?
biceps brachii is the agonist and triceps brachii is the antagonist.
Where is the biceps femoris located?
Biceps femoris is a muscle of the posterior compartment of the thigh, and lies in the posterolateral aspect. It arises proximally by two 'heads', termed the 'long head' (superficial) and the 'short head' (deep). It is part of the hamstrings. [1] [2] [1] Anatomy[edit| edit source] Origin[edit| edit source]
How many heads does the biceps femoris have?
Clinical relevance[edit| edit source] We know that biceps femoris muscle usually has 2 heads, namely short head and long head of biceps femoris. These two heads insert on the head of fibula, where at the site of insertion they divide into two portions by fibular collateral ligaments.
Does foam rolling help quadriceps?
The present study offers findings that foam rolling to quadricepsalone is effective in decreasing the activation of biceps femoris muscle. Foam rolling on patients muscle can lead to alteration in range of motion, performance and muscular co-activation around the particular joint.
What muscle is the biceps femoris?
Long head of muscle highlighted in red, short head (yellow) labeled in the lower part of the image. The biceps femoris ( / ˈbaɪsɛps ˈfɛmərɪs /) is a muscle of the thigh located to the posterior, or back.
Where is the biceps femoris located?
FMA. 22356. Anatomical terms of muscle. The biceps femoris ( / ˈbaɪsɛps ˈfɛmərɪs /) is a muscle of the thigh located to the posterior, or back. As its name implies, it has two parts, one of which (the long head) forms part of the hamstrings muscle group.
Why is the long head of the biceps femoris a weaker knee flex
The long head of the biceps femoris is a weaker knee flexor when the hip is extended (because of active insufficiency ). For the same reason the long head is a weaker hip extender when the knee is flexed.
Which nerve innervates the biceps femoris?
It is a composite muscle as the short head of the biceps femoris develops in the flexor compartment of the thigh and is thus innervated by common fibular branch of the sciatic nerve (L5, S1), while the long head is innervated by the tibial branch of the sciatic nerve (L5, S1).
What nerve descends along the medial border of the lateral hamstring?
The tendon of insertion of this muscle forms the lateral hamstring; the common fibular (peroneal) nerve descends along its medial border.
Where does the aponeurosis tendon slip?
There is a second small insertional attachment by a small tendon slip into the lateral condyle of the tibia.
Description
Anatomy
- Origin
1. Long head: ischial tuberosity 2. Short head: linea aspera and lateral supracondylar line of the femur - Insertion
Lateral aspect of fibular head
Function
- Actions
1. Long head: flexes the knee, extends hip, laterally rotates lower leg when knee slightly flexed, assists in lateral rotation of the thigh when hip extended 2. Short head: flexes the knee, laterally rotates lower leg when knee slightly flexed This video is a good summary of the functions of the … - Functional contributions
1. Through a reversed origin insertion action, the long head gives posterior stability to the pelvis 2. Both heads provide rotary stability by preventing forward dislocation of the tibia on the femur during flexion 3. Its contributions to the arcuate ligament complex at the posterolateral corner o…
Clinical Relevance
- We know that biceps femoris muscle usually has 2 heads, namely short head and long head of biceps femoris. These two heads insert on the head of fibula, where at the site of insertion they divide into two portions by fibular collateral ligaments. Any sort of subluxation or dislocation of biceps femoris tendon or abnormal insertion of the tendon, and any or no trauma, meniscal insta…
Techniques
- Palpation
1. Position the client in prone lying with the knee in slight flexion 2. Starting distally locate the lateral proximal border of the popliteal fossa to locate the insertion of the tendon 3. Palpate the hamstrings laterally to locate the biceps femoris 4. Move palm toward the ischial tuberosity (pro… - Length Tension Testing / Stretching
1. With one hand, palpate the patient's ASIS and iliac crest with your thumb and index finger 2. With the other hand, support the patient's leg just above the ankle 3. Raise the patient's leg into hip flexion keeping the knee extended, and add internal rotation of the tibiato bias the biceps femori…
Trigger Point Referral Pattern
- Painreferred from TrPs in the lower half of the biceps femoris (long or short head) focuses on the back of the knee and may extend up the posterolateral area of the thigh as far as the crease of th...
Treatment
- Stretching
1. Position of patient is side lying and support is provided to lower leg with hip and knee flexed 2. Hold the upper leg and bring into abduction 3. During abduction, try to support the leg against your body, so that the patient can extend the knee whilst pressing the hip into flexion 4. With one han… - Quadriceps foam rolling
The present study offers findings that foam rolling to quadriceps alone is effective in decreasing the activation of biceps femoris muscle. Foam rolling on patients muscle can lead to alteration in range of motion, performance and muscular co-activation around the particular joint. According …
Overview
The biceps femoris is a muscle of the thigh located to the posterior, or back. As its name implies, it has two parts, one of which (the long head) forms part of the hamstrings muscle group.
Further reading
• Kumakura, Hiroo (July 1989). "Functional analysis of the biceps femoris muscle during locomotor behavior in some primates". American Journal of Physical Anthropology. 79 (3): 379–391. doi:10.1002/ajpa.1330790314. PMID 2504047.
• Marshall, John L.; Girgis, Fakhry G.; Zelko, Russel R. (1972). "The Biceps Femoris Tendon and Its Functional Significance". J Bone Joint Surg Am. 54 (7): 1444–1450. doi:10.2106/00004623-197254070-00006. PMID 4653628. Archived from the …
• Kumakura, Hiroo (July 1989). "Functional analysis of the biceps femoris muscle during locomotor behavior in some primates". American Journal of Physical Anthropology. 79 (3): 379–391. doi:10.1002/ajpa.1330790314. PMID 2504047.
• Marshall, John L.; Girgis, Fakhry G.; Zelko, Russel R. (1972). "The Biceps Femoris Tendon and Its Functional Significance". J Bone Joint Surg Am. 54 (7): 1444–1450. doi:10.2106/00004623-197254070-00006. PMID 4653628. Archived from the ori…
Structure
It has two heads of origin:
• the long head arises from the lower and inner impression on the posterior part of the tuberosity of the ischium. This is a common tendon origin with the semitendinosus muscle, and from the lower part of the sacrotuberous ligament.
• the short head, arises from the lateral lip of the linea aspera, between the adductor magnus and vastus lateralis extending up almost as high as the insertion o…
Function
Both heads of the biceps femoris perform knee flexion.
Since the long head originates in the pelvis it is involved in hip extension. The long head of the biceps femoris is a weaker knee flexor when the hip is extended (because of active insufficiency). For the same reason the long head is a weaker hip extender when the knee is flexed.
When the knee is semi-flexed, the biceps femoris in consequence of its oblique direction rotate…
Clinical significance
Avulsion of the biceps femoris tendon is common in sports that require explosive bending of the knee as seen in sprinting.
External links
• UWash - long head
• UWash - short head
• Anatomy photo:14:06-0100 at the SUNY Downstate Medical Center
• Anatomy photo:14:st-0402 at the SUNY Downstate Medical Center