MOB TCD

Anterior Thigh

Professor Emeritus Moira O’Brien

FRCPI, FFSEM, FFSEM (UK), FTCD

Trinity College

Dublin

Cutaneous Supply MOB TCD

Thigh

• Anterior muscle group: supplied by femoral nerve

• Sartorius• Quadriceps: rectus femoris, vastus

medialis, vastus intermedius and vastus lateralis

• Pectineus

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• Medial or adductor group: adductor longus, adductor brevis, adductor portion adductor magnus and gracillis are supplied by the obturator nerve

• Posterior group: hamstring, semimembranosus, semitendinosus, biceps femoris, adductor magnus, below femoral hiatus

• Supplied by sciatic nerve

Thigh MOB TCD

Femoral Sheath

• Anterior wall formed by transversalis fascia

• Posterior by fascia iliaca• Three compartments• Medial, short, is the femoral canal,

contains lymph gland • Opens into abdomen via femoral ring,

site of femoral hernia• Middle compartment contains femoral vein• Lateral, femoral artery and femoral branch of genito-

femoral nerve• Femoral nerve is outside sheath

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Quadriceps Femoris

• Rectus femoris• Vastus medialis• Vastus intermedius• Vastus lateralis• Forms the anterior portion of the

capsule of the knee joint• The largest muscle group in the body • Wastes rapidly if there is an effusion,

particularly the oblique portion of the vastus medialis

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Rectus Femoris

• Tendinous origin from the upper part of the anterior inferior iliac spine (epiphysis) and the groove above the acetabulum

• The most superficial portion of the quadriceps

• The most frequently strained • The only portion of the quadriceps

that crosses two joints • Flexes hip, extends knee• Femoral nerve

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Vastus Medialis

• Vastus medialis arises from the lower half of the trochanteric line

• The spiral line • The medial lip of the linea aspera• The oblique (horizontal) fibres arise

from the lower portion of the adductor magnus, helping to stabilise the patella

• Separate branch from femoral nerve

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• Arises from the upper half of the inter-trochanteric line

• The root of the greatertrochanter• The lateral lip of the gluteal

tuberosity• The lateral lip of the linea aspera • The oblique portion of the muscle

arises from the iliotibial band• Separate nerve supply• Helps to stabilise the patella• Lateralis is a common site for

muscle biopsies and for injections

Vastus Lateralis MOB TCD

Vastus Intermedius

• Arises from the upper two thirds of the anterior and lateral aspect of the shaft of the femur

• It is the deepest portion of the quadriceps and is a common site (with vastus lateralis) for myositis ossificans, after a direct blow to the thigh

• The articularis genu is inserted into the upper part of the suprapatellar bursa

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Quadriceps

• The rectus femoris forms the most superficial lamina of the quadriceps, passes anterior to the patella

• To form the anterior part of the patellar ligament

• The fibres of the medialis and the lateralis decussate cross in an X-shape and lie in a plane posterior to the rectus femoris

• Some of these fibres form the retinacular fibres • Their oblique portions are inserted into the sides of

the patella

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Quadriceps Femoris

• The vastus intermedius is the most posterior lamina, forms the main part of the patellar ligament

• It is the most powerful extensor • The patellar ligament is inserted into

the smooth upper portion of the tibial tuberosity

• The quadriceps are the extensors of the knee

• Only the rectus femoris portion arises above the hip joint, and therefore is also a flexor of the hip

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Weak Vastus Medialis Obliquus

• Lower most fibres of vastus medialis• Partly arise from the adductor

magnus• Straightens the pull on the quads

tendon and patella• Controls patella tracking during

flexion/extension of the knee • Fibres atrophy quickly after knee

injury (within 24 hours)• 10-15 ml of effusion inhibit VMO • VMO rehabilitation strength and

timing of contraction

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Abnormal Lower Limb Biomechanics

Anatomical anomalies• Femoral torsion• Genu valgum • Increased Q angle • High (Alta) patella• Tibial torsion• Overpronation• Q angles

males 140 and females 170

> 200 greater problems

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The Q-angle

• The Q-angle is the angle formed by a line drawn from the anterior superior iliac spine to the centre of the patella

• And a line drawn upwards from the attachment of the patellar ligament to the tibial tubercle passing through this point

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• Functionally, on standing, the normal angle is 10–15°

• With the knee at 90°of flexion, an angle of 6°is normal, while greater than 10°is abnormal

• Contraction of the quadriceps tends to displace the patella laterally in the femoral groove

• The oblique fibres of the vastus medialis and the bony prominence of the lateral femoral condyle resist this

The Q-angle MOB TCD

Osgood Schlatter

• In young athletes, the patellar ligament is stronger than the bone

• Which can lead to a traction apophysitis of the tibial tuberosity, Osgood Schlatter disease

• Jumpers’ knee is a lesion at the apex of the patella and the ligament

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Sartorius

• Sartorius arises from anterior superior illiac spine

• Forms lateral boundary of femoral triangle • Crosses adductor longus at apex• Lies anterior to femoral artery• Posterior to adductor longus lies the

profunda artery• Knife injury at apex can injury both arteries

and the main blood supply to lower limb• Sartorius lies on roof of subsartorial canal which

contains femoral artery

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• Inserted into upper third of medial surface of tibia

• Anterior to gracillis and semitendinosus, as part of the pes anserinum

• Separated by tibial intertendinous bursa

• Supplied by femoral nerve

Sartorius MOB TCD

Adductor Muscles

• Adductor longus • Adductor brevis • Portion of adductor

Magnus• Gracilis• Supplied by obturator

Nerve L2,3,4• Act with lower abdominals

to stabilise the pelvis

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Adductor Origins

lateral medial

inferior

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Adductor Longus

• Tendinous origin, pubic body, has a variable shape

• Inserted into medial lip of linea aspera

• Most frequently torn at proximal musculo-tendinous junction, which varies

• Or may tear at teno-periosteal junction

• Site of junction varies, medial or lateral, may be longer in some

• Anterior division obturator nerve

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Adductor Brevis

• Origin lower portion of body of pubis

• Inferior pubic ramus• Inserted into lower half of the

pectineal line • Upper half of the linea

aspera• Deep to adductor longus• Separates two divisions of

obturator nerve• Anterior division supplies it

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Adductor Magnus

• Triangular area of ischial tuberosity• Ramus of ischium and inferior

ramus of pubis• Inserted into medial lip of gluteal

tuberosity• Lateral lip of linea aspera• Medial supracondylar line• Adductor tubercle• Hiatus for popliteal vessels• Origin of oblique fibres of vastus medialis• Post division obturator nerve• Sciatic nerve below hiatus for femoral vessels

MOB TCD

Gracilis

• Gracilis is the weakest, most medial and superficial of the adductors

• Gracilis is the only one that crosses the knee joint

• It arises from a thin aponeurosis, lower half of the body and the inferior ramus of the pubis and part of the ramus of the ischium. It is strap like above

• It ends in a rounded tendon, inserted into the upper portion of the medial surface of the tibia between the sartorius and the semitendinosus

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• Gracilis is separated from sartorius and the semitendinosus by the tibial intertendinous bursa (pes anserinum)

• Gracilis is usually supplied by the anterior division of the obturator nerve, L2, 3, 4

• It adducts the hip and flexes and medially rotates the leg

Gracilis MOB TCD

The Tibial Intertendinous Bursa

• Inflammation of the tibial intertendinous bursa

• Must be differentiated from injury to the lower attachment of the medial collateral ligament of the knee

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Adductors

• The adductors adduct the femur and help to stabilise and counteract the rotation of the pelvis, particularly during the double support

• When the anterior limb is flexed and the posterior limb is extended

Carlsoo, 1972

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Adductor Muscle - Tendon StrainAdductor Muscle - Tendon Strain

Common in soccer is adductor muscle-tendon strain. Be aware of:

• Rectus Femoris• Sartorius• Rectus Abdominus• Pectineus• Adductor Magnus• Gracilis

MOB TCD

• If the hip is flexed, the adductors rotate the hip medially

• When the hip is extended the adductors can laterally rotate

• They can also flex the extended hip and extend the flexed hip

• At the beginning of the swing phase of walking they work synergistically with the iliopsoas

• At the end of the swing phase, they work with the hamstrings, which contract to prevent further hip flexion

Adductors MOB TCD

Pectineus

• The pectineus muscle is a short flat muscle, which forms part of the floor of the femoral triangle

• It arises from the anterior aspect of the superior ramus of the pubic bone and the fascia covering it

• It is inserted into the upper half of a line drawn from the lesser trochanter to the linea aspera and lies posterior to the femoral sheat

• It is supplied by a branch from the femoral nerve or the accessory obturator (L2, 3)

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• The pectineus is mainly a flexor of the thigh and a weak adductor

• There may occasionally be some fusion between the adductor longus and brevis or with the pectineus

• Doubling of the origin of the adductor longus or brevis may also take place

Pectineus MOB TCD

Psoas Major

Origin• Intervertebral discs, adjoining

bodies of T12-L5 vertebrae• Medial half, anterior aspect of five

lumbar transverse processes• Fibrous arches on the sides of the

bodies of the four upper four lumbar vertebrae, over four lumbar arteries

• Inserted into the lesser trochanter of femur

• Nerve L2,3,4

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Psoas Minor

• Minor • Origin • T12 –L1• Insertion• Arcuate line• Iliopubic eminence

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Psoas Major Muscle and Fascia

• The psoas is covered by fascia which is attached medially to the lumbar vertebrae

• To the fibrous arches • Medially along the brim of the

pelvis to the arcuate and pectineal lines

• Laterally, the fascia is attached to the transverse processes of the lumbar vertebrae

• Medial Arcuate Ligament is a thickening of fascia over the Psoas

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Psoas

• Flexes the hip when acting from above

• Lumbar plexus is formed inside the substance of psoas

• A strain of the psoas muscle may be the cause of chronic groin pain, and you must take care not to mistake it for an adductor strain

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Psoas bursa, between psoas and capsule of hip joint, may communicate with the synovial membrane of the joint

Psoas abscess will present in the groin

Psoas MOB TCD

The Iliopsoas

• The iliacus• Origin: iliac fossa and iliac crest• Inserted into the lateral aspect of the psoas

and into the femur below the lesser trochanter• Nerve L2,3 • The iliopsoas is an active postural or stabilising muscle

of the hip which helps to prevent hyperextension of the hip while standing

• Acting from above, the iliopsoas flexes the hip and may be either a medial or a lateral rotator; acting from below, psoas flexes spine

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• In walking, the iliopsoas is used to start swinging the leg forwards

• On level ground the leg moves forwards like a pendulum to complete the swing

• Stronger contraction of the iliopsoas is required when running or walking up a hill

• When climbing stairs, the iliopsoas lifts the leg and places the foot on the stair above

The Iliopsoas MOB TCD

• When preparing to stand from sitting, the iliopsoas pulls the trunk forwards as the femur is fixed

• The trunk leans forwards and, before standing upright, the centre of gravity of the trunk moves over the feet

• In sitting up from lying, the iliopsoas pulls on the pelvis and the lower vertebrae in order to pull the trunk up

Tyldesley & Grieve, 1989

The Iliopsoas MOB TCD

• Running with the legs lifted high, helps to develop the iliopsoas

• The iliopsoas is also used in the downbeat of freestyle swimming

• The iliopsoas is the main muscle involved in straight leg sit-ups

• These, however, should never be done as they put stress on the lumbar vertebrae and do nothing for the abdominal muscles

The Iliopsoas MOB TCD

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