Gluteal Region And Posterior Thigh

Front 1

muscles

Back 1

- organized into superficial and deep layers

- receive innervation from sacral plexus

- arterial supply from superior and inferior gluteal arteries

Front 2

superior gluteal artery and nerve

Back 2

exit via the superior sciatic foramen superior to the piriformis

Front 3

inferior gluteal artery and nerve

Back 3

exit via the superior sciatic foramen inferior to the piriformis

Front 4

IT Band

Back 4

- aponeurosis of the gluteus maximus and TFL blend and thicken the fascia lata along the lateral thigh to form the IT tract

- IT band attaches distally on the anterolaterral aspect of the tibia at Gerdy's Tubercle

Front 5

Gluteus Maximus

Back 5

- strong hip extensor

- several gluteal bursae seperate the gluteus maximus from underlying structures including the greater trochanter and ischial tuberosity

Front 6

gluteus medius and minimus

Back 6

- primary abductors of the thigh

- branch of the superior gluteal artery and the superior gluteal nerve travel between and supply gluteus medius and minimus as they course towards TFL (also supply)

Front 7

Trendelenburg Test

Back 7

- injury to the superior gluteal nerve and/or weakness of the glut med/min can be determined by this test

- when pt stands on one leg glut med/min should contract on weight bearing leg to maintain stable pelvis in the frontal plane

- if muscles not functionally correct, pt will be unable to sustain a stable pelvis

**pelvis on the opp unloaded limb will drop resulting in a positive terndelenburg sign

Front 8

Injury to the superior gluteal nerve (L1, S1)

Back 8

- results in characteristic gait or gluteus medius (duchenne) limp

- pt compensates for weak abductors by listing the trunk over the involved side

- with bilateral weakness the pt will exhibit a waddling gait

Front 9

TFL

Back 9

acts primarily as a flexor and medial rotator of the thigh

**can effectively abduct the thigh but only when the hip is already flexed

Front 10

deep muscles of gluteal region

Back 10

- all primarily function as a lateral (external) rotators of the thigh and as stabilizers of the hip joint posteriorly.

- innervated by various branches of the sacral plexus

- arterial supply via inferior gluteal artery

Front 11

piriformis

Back 11

- attaches proximaly too deep surface of sacrum and exits pelvis through the greater sciatic foramen to reach distal attachment on greater trochanter

- superior and inferior gluteal nerves and arteries exit above and below it respectively

- large sciatic nerve exits below piriformis

- location can be imagined by by drawing a line between PSIS and superior boarder of greater trochanter

- intragluteal injections should be made well superior to this line to avoid underlying structures

Front 12

obturator internus

Back 12

- covers internal portion of the obturator membrane and foramen

- exits pelvis through lesser sciatic foramen

- makes a right turn and ends as a long tendon which attaches to the greater trochanter

- tnedon of OI located inferior to piriformis lying between the superior and inferior gemelli
**these three form a three headed muscle

Front 13

quadratus femoris

Back 13

- short rectangular muscle which shares an innervation with inferior gemelli

Front 14

posterior compartment muscles

Back 14

- can flex the leg and extend the thigh

- share a proximal attachement on ischial tuberosity

- when knee is flexed some muscles medially rotate and others laterally rotate

- all are innervated by the tibial division of the sciatic nerve except the short head of the biceps femoris

- arterial supply= perforating branches off the deep femoral artery

Front 15

Biceps femoris

Back 15

- has a long and short head

- only the long head functions as a true hamstring

- only the long head crosses the hip with a proximal attachment at the ischial tuberosity

- flexes the leg and extends the thigh

- two heads do share a common insertion on the fibular head

Front 16

biceps femoris innervation

Back 16

- long head innervated by tibial division of sciatic

- short head innervated by common fibular division sciatic

Front 17

semitendinosus

Back 17

- cord like distal attachment at pes anserine at superomedial tibia

Front 18

things that attach at pes anserine

Back 18

- semitenditinosus

- gracilis

- sartorius

Front 19

semimenbranosus

Back 19

- distal tendon divides into 3 Parts:

1. attaches to medial tibial condyle

2. blends with the popliteal fossa

3. reinforces joint capsule at oblique popliteal ligament

Front 20

severe hamstring strains

Back 20

- may result in partial avulsion of a tendon at the ischial tuberosity

Front 21

adductor magnus

Back 21

- sometimes classified as a hamstring

- ishiocondylar part of the adductor magnus shares same innervation as hamstrings (tibial division sciatic nerve)

- does not cross the knee to flex the leg so does not function as a true hamstring

- distal fibers of adductor magnus attach just superiorly to the proximal attachement of the short head of the biceps femoris

Front 22

peripheral nerves in the posterior thigh

Back 22

- are derived from the sacral plexus

Front 23

posterior cutaneous nerve of the thigh

Back 23

- formed from anterior and posterior divisions of ventral rami of the sacral plexus (S1, S2, S3)

- supplies skin over inferior gluteal area (via cluneal branches)

- supplies posteiror thigh and proximal leg

- enters gluteal region through greater sciatic foramen inferior to piriformis and medial to sciatic nerve

Front 24

sciatic nerve

Back 24

- largest nerve in the body

- emerges from greater sciatic foramen inferior to piriformis

- located lateral to the posterior cutaneous nerve of the thigh, internal pudendal vessels and nerve

- emerges from inferior boarder of gluteus maximus to descend into posterior thigh deep to biceps femoris and superficial to adductor magnus

Front 25

Sciatic nerve innervations

Back 25

- supplies no muscles in the gluteal region

- does supply most of the posterior thigh and then entire leg and foot

- also supplies skin over most of the leg and foot

Front 26

sciatic nerve bifurcation

Back 26

- really two nerves enclosed in a sheath

- bifurcates at apex of popliteal fossa

Front 27

tibial nerve

Back 27

- derived from anterior divisions of ventral rami L4, L5, S1, S2, S3

- supplies all the muscles of the posterior thigh except the short head of the biceps femoris

- also supplies the hamstring part of the adductor magnus

Front 28

common fibular nerve

Back 28

- derived from posterior divisions of ventral rami L4, L5, S1, S2

- only structure it supplies in posterior thigh is short head of the biceps femoris

Front 29

arteries

Back 29

posterior thigh does not have a major artery passing through it

3 of the 4 perforating branches of the deep femoral artery pierce the adductor magnus to enter and supply most of the posterior compartment

small contributions from inferior gluteal, medial circumflex femoral and popliteal arteries