The gluteal region pdf - Lower limb

C H A P T E R O U T L I N E

(continued)

Common Peroneal Nerve 479

Posterior Cutaneous Nerve of the

Thigh 479

Obturator Nerve 479

Fascial Compartments of the Leg 479

Interosseous Membrane 479

Retinacula of the Ankle 479

The Front of the Leg 481

Skin 481

Contents of the Anterior Fascial

Compartment of the Leg 481

Contents of the Lateral Fascial

Compartment of the Leg 486

The Back of the Leg 487

Skin 487

Contents of the Posterior Fascial

Compartment of the Leg 487

The Region of the Ankle 490

Anterior Aspect of the Ankle 490

Posterior Aspect of the Ankle 490

The Foot 490

The Sole of the Foot 490

The Dorsum of the Foot 498

Joints of the Lower Limb 500

Knee Joint 500

Proximal Tibiofibular Joint 504

Distal Tibiofibular Joint 504

Ankle Joint 505

Tarsal Joints 507

Tarsometatarsal and Intermetatarsal

Joints 508

Metatarsophalangeal and

Interphalangeal Joints 508

The Foot as a Functional Unit 508

The Foot as a Weight Bearer

and a Lever 508

Radiographic Anatomy 512

Radiographic Appearances of the Lower

Limb 512

Surface Anatomy 512

Gluteal Region 513

Inguinal Region 513

Femoral Triangle 520

Adductor Canal 520

Knee Region 520

Tibia 521

Ankle Region and Foot 521

C H A P T E R O B J E C T I V E S

The basic anatomy of the vascular supply, lymphatic drainage,

is given. Emphasis is placed on the functions of the muscles, and

A general description of the bones, joints, and actions of muscles

surgery, or an emergency department.

■

Lower limb problems are some of the most common dealt with

by health professionals, whether working in general practice,

■

Arthritis, varicose veins, vascular deficiencies, fractures,

dislocations, sprains, lacerations, knee effusions, leg pain,

ankle injuries, and peripheral nerve injuries are just a few of the

conditions that physicians see.

■

The anatomy of the lower limb is discussed in relation to com-

mon clinical conditions.

■

only the briefest coverage of their attachments is provided.

■

and distribution of the nerves is reviewed.

natomy

asic

The primary function of the lower limbs is to support the

nerves (anterior rami).

branches of the iliohypogastric (L1) and 12th thoracic

The upper lateral quadrant is supplied by the lateral

three sacral nerves.

rami of the upper three lumbar nerves and the upper

The upper medial quadrant is supplied by the posterior

posterior and anterior rami of spinal nerves, as follows:

(Figs. 10.1 and 10.2) are derived from

cutaneous nerves

The

layer of superficial fascia.

region is largely made up of the gluteal muscles and a thick

the iliac crest and inferiorly by the fold of the buttock. The

The gluteal region, or buttock, is bounded superiorly by

its own distinct nerve and blood supply.

having its own muscles that perform group functions and

and the leg are compartmentalized, each compartment

thigh, the knee, the leg, the ankle, and the foot. The thigh

The lower limbs are divided into the gluteal region, the

stable and can bear the weight of the body.

each other at the symphysis pubis, the lower limbs are very

the trunk at the strong sacroiliac joints and anteriorly with

Because the two hip bones articulate posteriorly with

ized for locomotion.

standing, walking, and running; they have become special

weight of the body and to provide a stable foundation in

Organization of the Lower Limb

The Gluteal Region

The Skin of the Buttock

■

Basic Anatomy

437

posterior rami of
upper three
lumbar nerves

posterior rami of
upper three
sacral nerves

sural nerve

branches of
saphenous nerve

medial calcaneal
nerve

medial plantar
nerve

lateral plantar
nerve

sural nerve

sural communicating
branch of common
peroneal nerve

posterior cutaneous
nerve of thigh

branches of lateral
cutaneous nerve
of thigh

branches of
posterior cutaneous
nerve of thigh

branches of lateral
cutaneous nerve
of thigh

lateral branches of
iliohypogastric (LI) nerve

lateral branch of
12th thoracic nerve

lateral cutaneous
nerve of calf

FIGURE 10.1

Cutaneous nerves of the posterior surface of

the right lower limb.

lateral cutaneous
branch of 12th
thoracic nerve

lateral cutaneous
nerve of thigh

intermediate
cutaneous nerve
of thigh

patellar plexus
of nerves

lateral sural
cutaneous nerve

superficial peroneal
nerve

deep peroneal
nerve

saphenous nerve

infrapatellar branch
of saphenous nerve

medial cutaneous
nerve of thigh

obturator nerve

ilioinguinal nerve

femoral branch of
genitofemoral nerve

FIGURE 10.2

Cutaneous nerves of the anterior surface of

gluteus maximus.

muscle and receives the greater part of the insertion of the

The iliotibial tract forms a sheath for the tensor fasciae latae

the iliac crest and below to the lateral condyle of the tibia.

(Fig. 10.6). This is attached above to the tubercle of

tract

iliotibial

cia is thickened to form a strong, wide band, the

to the iliac crest. On the lateral surface of the thigh, the fas

ers the outer surface of the gluteus medius and is attached

the gluteus maximus, it continues as a single layer that cov

to enclose the gluteus maximus muscle (Fig. 10.5). Above

of the thigh. In the gluteal region, it splits

deep fas

is continuous below with the

deep fascia

The

the prominence of the buttock.

impregnated with large quantities of fat. It contributes to

is thick, especially in women, and is

superficial fascia

The

superficial inguinal nodes (Figs. 10.3 and 10.4).

drain into the lateral group of the

lymph vessels

The

sacral and coccygeal nerves.

the buttocks is supplied by small branches of the lower

The skin over the coccyx in the floor of the cleft between

anterior rami).

the posterior cutaneous nerve of the thigh (S1, 2, and 3,

The lower medial quadrant is supplied by branches from

rior rami).

the lateral cutaneous nerve of the thigh (L2 and 3, ante

The lower lateral quadrant is supplied by branches from

the right lower limb.

■

Fascia of the Buttock

cia,

fascia lata,

Bones of the Gluteal Region

Hip Bone

The ilium, ischium, and pubis form the hip bone (Figs. 10.7

posterior

a similar prominence, the

inferior iliac spine;

anterior

anterior superior iliac spine is a prominence, the

2 in. (5 cm) behind the anterior superior spine. Below the

lies about

iliac tubercle

The

terior superior iliac spine.

pos

and behind at the

anterior superior iliac spine

through the skin along its entire length; it ends in front at

(Fig. 10.8). This can be felt

iliac crest

bone, possesses the

which is the upper flattened part of the

ilium,

The

the hip bone in the gluteal region are as follows.

The important features found on the outer surface of

bony pelvis is considered on page 241.

pubis. The detailed structure of the internal aspect of the

articulate with one another anteriorly at the symphysis

and form the anterolateral walls of the pelvis; they also

hip bones articulate with the sacrum at the sacroiliac joints

and 10.8). They meet one another at the acetabulum. The

the

438

CHAPTER 10

The Lower Limb

deep fascia
of thigh
(fascia lata)

femoral
sheath

femoral vein

femoral artery

saphenous
opening

falciform
margin

great saphenous
vein

attachment of membranous
layer of superficial fascia

horizontal group of
superficial inguinal
lymph nodes

femoral artery

vertical group of superficial inguinal lymph nodes

great saphenous
vein

superficial external
pudendal vessels

superficial epigastric vessels

superficial circumflex iliac vessels

inguinal ligament

fascia

a lata)

ral

ein

tery

nous

orm

gin

great saphenous

attachment of membranous
layer of superficial fascia

horizontal group of
superficial inguinal
lymph nodes

femoral artery

gg
ve

superficial epi

superficial circumflex

inguinal ligament

femoral canal

FIGURE 10.3

A, B.

superficial fascia to the deep fascia, about a fingerbreadth below the inguinal ligament.

in the deep fascia and its relationship to the femoral sheath. Note also the line of attachment of the membranous layer of

Superficial veins, arteries, and lymph nodes over the right femoral triangle. Note the saphenous opening

umbilicus

lymph from lower half

of anal canal

iliac crest

popliteal lymph nodes

femoral canal

external iliac nodes

deep inguinal nodes

saphenous

opening

vertical group of

superficial

inguinal

lymph nodes

horizontal group

of superficial

inguinal

lymph nodes

superficial

inguinal

nodes

FIGURE 10.4

Lymph drainage for the superficial tissues of the right lower limb and the abdominal walls below the level of

the femoral canal.

ous opening in the deep fascia. Note also that all lymph from these nodes ultimately drains into the external iliac nodes via

the umbilicus. Note the arrangement of the superficial and deep inguinal lymph nodes and their relationship to the saphen-

Basic Anatomy

(Fig. 10.8).

acetabular fossa

called the

cartilage. The floor of the acetabulum is nonarticular and is

ited to a horseshoe-shaped area and is covered with hyaline

(Fig. 10.8). The articular surface of the acetabulum is lim

acetabular notch

ulum is deficient and is marked by the

(Figs. 10.8 and 10.9). The inferior margin of the acetab

almost spherical head of the femur to form the hip joint

which articulates with the

acetabulum,

sion, called the

On the outer surface of the hip bone is a deep depres

(Figs. 10.7 and 10.8).

pubic tubercle

ends laterally as the

forms the upper border of the body of the pubis, and it

pubic crest

(see page 245). The

obturator membrane

The obturator foramen in life is filled in by

tor foramen.

obtura

inferior ramus joins the ischial ramus below the

joins the ilium and ischium at the acetabulum, and the

the superior ramus

symphysis pubis;

line anteriorly at the

the two pubic bones articulate with each other in the mid

(Fig. 10.8). The bodies of

inferior ramus

ramus,

superior

body,

can be divided into a

The

sacrospinous and sacrotuberous ligaments (see page 245).

by the presence of the

lesser sciatic foramina

greater

The greater and lesser sciatic notches are converted into

posterior aspect of the lower part of the body of the bone.

forms the

ischial tuberosity

The

lesser sciatic notches.

greater

border of the ischium and intervenes between the

projects from the posterior

ischial spine

10.7 and 10.8). The

(Figs.

ramus

and a lower thinner part, the

body,

part, the

is L shaped, possessing an upper thicker

ischium

The

(Figs. 10.7

greater sciatic notch

possesses a large notch, the

iliac spine. Above and behind the acetabulum, the ilium

is located below the posterior superior

inferior iliac spine,

439

and 10.8).

and

pubis

and an

the

In the anatomic position, the front of the

sis

symphy

femur are shown in Figures 10.10 and 10.11.

The important muscles and ligaments attached to the

medial epicondyle.

10.11). The adductor tubercle is continuous with the

(Fig.

lateral epicondyles

medial

condyles are the

take part in the formation of the knee joint. Above the

by an articular surface for the patella. The two condyles

The anterior surfaces of the condyles are joined

notch.

intercondylar

condyles, separated posteriorly by the

medial

lateral

The lower end of the femur has

(Fig. 10.11).

popliteal surface

area on its posterior surface called the

broader toward its distal end and forms a flat, triangular

ment of the gluteus maximus muscle. The shaft becomes

for the attach

gluteal tuberosity

greater trochanter is the

On the posterior surface of the shaft below the

lar ridge.

lateral supracondy

becomes continuous below with the

on the medial condyle (Fig. 10.11). The lateral margin

cle

adductor tuber

to the

medial supracondylar ridge

above and below. The medial margin continues below as

muscular septa. The margins of the linea aspera diverge

(Fig. 10.11), to which are attached muscles and inter

linea aspera

anterior surface but posteriorly has a ridge, the

of the femur is smooth and rounded on its

The

(Fig. 10.11).

tubercle

quadrate

posteriorly, on which is the

trochanteric crest

inter

ofemoral ligament is attached, and a prominent

anteriorly, where the ili

intertrochanteric line

are the

(Figs. 10.10 and 10.11). Connecting the two trochanters

nences situated at the junction of the neck and the shaft

are large emi

lesser trochanters

greater

The

axis of the shaft. The size of this angle can be altered by

of about 125° (slightly less in the female) with the long

downward, backward, and laterally and makes an angle

which connects the head to the shaft, passes

neck,

The

ment and enters the bone at the fovea.

femur from the obturator artery is conveyed along this liga

of the head. Part of the blood supply to the head of the

for the attachment of the ligament

fovea capitis,

called the

(Fig. 10.9). In the center of the head is a small depression,

with the acetabulum of the hip bone to form the hip joint

forms about two thirds of a sphere and articulates

head

greater and lesser trochanters (Figs. 10.10 and 10.11). The

The upper end of the femur has a head, a neck, and

form the knee joint.

the hip joint and below with the tibia and the patella to

The femur articulates above with the acetabulum to form

Femur

outer surface of the hip bone are shown in Figure 10.8.

The important muscles and ligaments attached to the

downward.

anterior surface of the sacrum is directed forward and

symphysis pubis faces upward and backward and the

vertical plane. This means that the pelvic surface of the

pubis and the anterior superior iliac spines lie in the same

disease.

and

shaft

the

and

deep fascia

tensor fasciae latae

gluteus medius

iliotibial tract

vastus lateralis

deep fascia (fascia lata)

long head of biceps

semitendinosus

adductor magnus

gracilis

gluteus maximus

FIGURE 10.5

Right gluteus maximus muscle.

440

CHAPTER 10

The Lower Limb

anterior superior iliac spine

lateral cutaneous nerve of thigh

sartorius

femoral nerve

lateral femoral

circumflex artery

intermediate cutaneous nerve

of thigh

nerve to vastus medialis

vastus intermedius

vastus lateralis

vastus medialis

shaft of femur

iliotibial tract

rectus femoris

ligamentum patellae

saphenous nerve

femoral artery

gracilis

adductor magnus

adductor longus

medial cutaneous nerve of thigh

pectineus

spermatic cord

deep external pudendal artery

pubic tubercle

inguinal ligament

femoral canal

femoral sheath

femoral vein

psoas

iliacus

profunda femoris artery

tensor fasciae latae

medial femoral

circumflex artery

femoral artery

FIGURE 10.6

Femoral triangle and adductor (subsartorial) canal in the right lower limb.

Basic Anatomy

441

iliac crest

rough surface for attachment of
interosseous ligament

posterior superior
iliac spine

auricular surface

posterior inferior iliac spine

greater sciatic notch

ischial spine

lesser sciatic notch

obturator membrane

ischial tuberosity

ischial ramus

inferior ramus of pubis

obturator canal

pubic crest

pubic tubercle

body of pubis

superior ramus
of pubis

iliopectineal line

anterior inferior
iliac spine

anterior superior
iliac spine

iliac fossa

ilium

tubercle of ilium

line of fusion of bones

acetabulum

obturator foramen

ischium

pubis

posterior superior
iliac spine

auricular surface

posterior inferior iliac spine

greater sciatic notch

ischial spine

lesser sciatic notch

obturator membrane

ischial tuberosity

ramus

ferior

fossa

ilium

line of fusion of bones

obt

ischium

FIGURE 10.7

Medial surface (

(the ilium, the ischium, and the pubis).

) of the right hip bone. Note the lines of fusion between the three bones

) and lateral surface (

iliac crest

posterior gluteal line

gluteus maximus

posterior inferior

iliac spine

sacrotuberous ligament

posterior superior

iliac spine

greater sciatic notch

capsule

ischial spine

sacrospinous ligament

gemellus superior
lesser sciatic notch

gemellus inferior

sacrotuberous ligament

semimembranosus

semitendinosus

biceps femoris

ischial tuberosity

quadratus femoris

adductor magnus

ramus of ischium

obturator foramen

acetabular notch

obturator externus

gracilis

inferior ramus of pubis

adductor brevis

body of pubis

adductor longus

pubic tubercle

inguinal ligament

pubic crest

pectineus

superior ramus of pubis

pectineal line

acetabular fossa

reflected head of rectus femoris

anterior inferior iliac spine

inferior gluteal line

sartorius

inguinal ligament

anterior superior

iliac spine

tensor fasciae latae

gluteus minimus

iliac tubercle

middle gluteal line

gluteus medius

straight head of rectus femoris

FIGURE 10.8

xternal surface of the right hip bone.

Muscles and ligaments attached to the e

442

CHAPTER 10

The Lower Limb

gluteus maximus

gemellus superior

gemellus inferior

semitendinosus

biceps femoris

adductor magnus

semimembranosus

psoas

iliacus

pectineus

adductor magnus

adductor longus

vastus medialis

vastus lateralis

adductor brevis

vastus intermedius

gluteus maximus

quadratus femoris

obturator externus

gluteus medius

rectus femoris

sartorius

tensor fasciae latae

gluteus minimus

gluteus medius

FIGURE 10.9

xternal surface of the right hip bone and the posterior surface of the femur.

Muscles attached to the e

Tenderness of the Head of the Femur and Arthritis of

the Hip Joint

The head of the femur—that is, that part that is not intra-

Fractures of the neck of the femur are common and are of two

of the neck of the femur and in slipping of the femoral epiphysis.

and it occurs in fractures

in this angle is referred to as

The neck of the femur is inclined at an angle with the shaft; the

Fractures of the femoral neck interfere with or completely inter

synovial membrane. As long as the epiphyseal cartilage remains,

explains why avascular necrosis of the head can occur after

just inferior to the inguinal ligament and just lateral to the pulsat

acetabular—can be palpated on the anterior aspect of the thigh

ing femoral artery. Tenderness over the head of the femur usu-

ally indicates the presence of arthritis of the hip joint.

Blood Supply to the Femoral Head and Neck

Fractures

Anatomic knowledge of the blood supply to the femoral head

fractures of the neck of the femur. In the young, the epiphysis

of the head is supplied by a small branch of the obturator artery,

which passes to the head along the ligament of the femoral

head. The upper part of the neck of the femur receives a profuse

blood supply from the medial femoral circumflex artery. These

branches pierce the capsule and ascend the neck deep to the

no communication occurs between the two sources of blood. In

the adult, after the epiphyseal cartilage disappears, an anasto-

mosis between the two sources of blood supply is established.

rupt the blood supply from the root of the femoral neck to the

femoral head. The scant blood flow along the small artery that

accompanies the round ligament may be insufficient to sustain

the viability of the femoral head, and ischemic necrosis gradually

takes place.

The Neck of the Femur and Coxa Valga and Coxa Vara

angle is about 160° in the young child and about 125° in the adult.

An increase in this angle is referred to as coxa valga, and it

occurs, for example, in cases of congenital dislocation of the hip.

In this condition, adduction of the hip joint is limited. A decrease

coxa vara,

In this condition, abduction of the hip joint is limited. Shenton’s

line is a useful means of assessing the angle of the femoral neck

on a radiograph of the hip region (see Fig. 10.72).

Fractures of the Femur

types, subcapital and trochanteric. The subcapital fracture

occurs in the elderly and is usually produced by a minor trip or

stumble. Subcapital femoral neck fractures are particularly com-

mon in women after menopause. This gender predisposition is

because of a thinning of the cortical and trabecular bone caused

C L I N I C A L N O T E S

(continued)

Basic Anatomy

443

neck

piriformis

greater trochanter

gluteus minimus

iliofemoral ligament

vastus lateralis

intertrochanteric line

vastus intermedius

patellar surface

lateral
ligament

medial ligament

capsule of knee joint

articularis genus

vastus medialis

lesser trochanter

psoas

pubofemoral ligament

capsule of hip joint

fovea capitis

ligament of head

head

FIGURE 10.10

Muscles and ligaments attached to the ante

rior surface of the right femur.

ischiofemoral
ligament

capsule of hip joint

lesser trochanter

psoas

iliacus

pectineus

adductor brevis

vastus medialis

linea aspera

adductor longus

site of hiatus of
adductor magnus

medial supracondylar ridge

gastrocnemius (medial head)

adductor magnus

adductor tubercle

medial condyle

intercondylar notch

lateral condyle

lateral epicondyle

gastrocnemius
(lateral head)

capsule of knee joint

plantaris

popliteal surface

lateral supracondylar
ridge

biceps femoris
(short head)

vastus lateralis

vastus intermedius

adductor magnus

gluteus maximus

quadratus femoris

quadrate tubercle

gluteus medius

obturator externus

greater trochanter

head

intertrochanteric crest

medial epicondyle

ligament of
head of femur

FIGURE 10.11

Muscles and ligaments attached to the poste

siderable displacement occurs. The strong muscles of the thigh

rior surface of the right femur.

by estrogen deficiency. Avascular necrosis of the head is a

common complication. If the fragments are not impacted, con-

(Fig. 10.12), including the rectus femoris, the adductor muscles,

correct length before manipulation and operative therapy to

ferent actions of the muscles of the leg is necessary to under

From these accounts, it is clear that knowledge of the dif

ment is smaller and is rotated backward by the gastrocnemius

tures of the middle third of the shaft. However, the distal frag

distal fragment is also rotated backward by the pull of the two

ment is adducted by the adductor muscles, pulled upward by the

gemelli, and the quadratus femoris (Fig. 10.13). The lower frag

femur, the proximal fragment is flexed by the iliopsoas; abducted

bone fragments are not impacted, the pull of the strong muscles

capsular, and both fragments have a profuse blood supply. If the

commonly occur in the young and

and the quadratus femoris rotate the distal fragment laterally, as

and the hamstring muscles, pull the distal fragment upward, so

that the leg is shortened (as measured from the anterior superior

iliac spine to the adductor tubercle or medial malleolus). The glu-

teus maximus, the piriformis, the obturator internus, the gemelli,

seen by the toes pointing laterally.

Trochanteric fractures

middle aged as a result of direct trauma. The fracture line is extra-

will produce shortening and lateral rotation of the leg, as previ-

ously explained.

Fractures of the shaft of the femur usually occur in young and

healthy persons. In fractures of the upper third of the shaft of the

by the gluteus medius and minimus; and laterally rotated by

the gluteus maximus, the piriformis, the obturator internus, the

hamstrings and quadriceps, and laterally rotated by the adduc-

tors and the weight of the foot (Fig. 10.13).

In fractures of the middle third of the shaft of the femur,

the distal fragment is pulled upward by the hamstrings and the

quadriceps (Fig. 10.13), resulting in considerable shortening. The

heads of the gastrocnemius (Fig. 10.13).

In fractures of the distal third of the shaft of the femur, the

same displacement of the distal fragment occurs as seen in frac-

muscle (Fig. 10.13) to a greater degree and may exert pressure

on the popliteal artery and interfere with the blood flow through

the leg and foot.

stand the displacement of the fragments of a fractured femur.

Considerable traction on the distal fragment is usually required

to overcome the powerful muscles and restore the limb to its

bring the proximal and distal fragments into correct alignment.

444

CHAPTER 10

The Lower Limb

GAST

QDF

GAST

QDF

HAM

GME
GMI

popliteal

artery

HAM

type 3

OI
GE
QF

type 1

type 2

type 4

FIGURE 10.12

muscles; HS, hamstring muscles.

gluteus maximus; PI, piriformis; OI, obturator internus; GE, gemelli; QF, quadratus femoris; RF, rectus femoris; AM, adductor

powerful muscles. Note in particular the outward rotation of the leg so that the foot characteristically points laterally. GM,

Displacement of the lower bone fragment caused by the pull of the

Fractures of the neck of the femur. B.

FIGURE 10.13

Fractures of the shaft of the femur.

tus femoris; AM, adductor muscles; QDF, quadriceps femoris; HAM, hamstrings; GAST, gastrocnemius.

gluteus medius; GMI, gluteus minimus; GM, gluteus maximus; PI, piriformis; OI, obturator internus; GE, gemelli; QF, quadra

fragment caused by the pull of the gastrocnemius muscle, threatening the integrity of the popliteal artery. IP, iliopsoas; GME,

Lower third of the femoral shaft. Note the excessive displacement of the lower

caused by the gastrocnemius muscle.

Middle third of the femoral shaft. Note the posterior displacement of the lower fragment

pull of the powerful muscles.

Upper third of the femoral shaft. Note the displacement caused by the

Basic Anatomy

Posterior cutaneous nerve of the thigh

Sciatic nerve

Piriformis

The following structures exit the foramen (Fig. 10.15):

pelvis into the gluteal region.

and sacrospinous ligaments. It provides an exit from the

greater sciatic notch of the hip bone and the sacrotuberous

The greater sciatic foramen (see Fig. 6.11) is formed by the

Greater Sciatic Foramen

greater sciatic foramen and the lesser sciatic foramen.

The two important foramina in the gluteal region are the

to the spine of the ischium (Fig. 10.14; see Fig. 6.1).

The sacrospinous ligament connects the back of the sacrum

Sacrospinous Ligament

sacrum to the ischial tuberosity (Fig. 10.14; see Fig. 6.1).

The sacrotuberous ligament connects the back of the

Sacrotuberous Ligament

the sacroiliac joint by the weight of the vertebral column.

ligaments is to stabilize the sacrum and prevent its rotation at

rotuberous and sacrospinous ligaments. The function of these

The two important ligaments in the gluteal region are the sac

445

Ligaments of the Gluteal Region

Foramina of the Gluteal Region

■

posterior superior iliac spine

superior gluteal nerve

piriformis

sacrotuberous ligament

inferior gluteal artery

coccyx

sacrospinous ligament

internal pudendal artery

pudendal nerve

body of pubis

nerve to quadratus femoris

ischial tuberosity

adductor magnus

medial femoral circumflex artery

posterior cutaneous nerve of thigh

sciatic nerve

iliopsoas tendon

quadratus femoris

obturator externus

greater trochanter

gemellus inferior

obturator internus

gemellus superior

ischial spine

tensor fasciae latae

inferior gluteal nerve

straight

reflected

head of

rectus femoris

gluteus minimus

iliac crest

superior gluteal artery

nerve to obturator

internus

FIGURE 10.14

Deep structures in the right gluteal region; the gluteus maximus and the gluteus medius muscles have been

completely removed.

446

CHAPTER 10

The Lower Limb

posterior superior iliac spine

sacrotuberous ligament

superior gluteal artery

inferior gluteal artery

and nerve
spine of ischium

nerve to

obturator internus

pudendal nerve

sacrospinous ligament

internal pudendal artery

coccyx

ischiorectal fossa

anus

fat

semimembranosus

gracilis

nerve to hamstrings

adductor magnus

semitendinosus

biceps femoris

gluteus maximus

sciatic nerve

iliotibial tract

adductor magnus

quadratus femoris

posterior cutaneous nerve

of thigh

greater trochanter

gemellus superior

piriformis

superior gluteal nerve

tensor fasciae latae

gluteus minimus

superior gluteal artery

gluteus medius

iliac crest

gemellus inferior

oburator internus

FIGURE 10.15

Structures in the right gluteal region. The greater part of the gluteus maximus and part of the gluteus medius

extended position.

gluteus maximus muscle in maintaining the knee in the

to its insertion in the iliotibial tract and thus assists the

The tensor fasciae latae runs downward and backward

largely responsible for the prominence of the buttock.

the body. It lies superficial in the gluteal region and is

The gluteus maximus (Fig. 10.5) is the largest muscle in

Note the following:

and described in Table 10.1.

The muscles are shown in Figures 10.5, 10.14, and 10.15

superior and inferior gemelli, and the quadratus femoris.

fasciae latae, the piriformis, the obturator internus, the

mus, the gluteus medius, the gluteus minimus, the tensor

The muscles of the gluteal region include the gluteus maxi

Internal pudendal artery and vein

Pudendal nerve

Nerve to obturator internus

Tendon of obturator internus muscle

(Fig. 10.14):

The following structures pass through the foramen

the perineum below the pelvic floor.

the greater sciatic foramen above the pelvic floor to enter

nerves and blood vessels that have left the pelvis through

the perineum from the gluteal region. Its presence enables

and sacrospinous ligaments. It provides an entrance into

lesser sciatic notch of the hip bone and the sacrotuberous

The lesser sciatic foramen (see Fig. 6.11) is formed by the

Lesser Sciatic Foramen

Internal pudendal artery and vein

Superior and inferior gluteal arteries and veins

Pudendal nerve

Nerves to the obturator internus and quadratus femoris

Superior and inferior gluteal nerves

have been removed.

■

Muscles of the Gluteal Region

■

Basic Anatomy

447

Muscles of the Gluteal Region

T A B L E 1 0 . 1

Tensor fasciae

Muscle

Origin

Insertion

Nerve Supply

Nerve Root

Action

Gluteus

maximus

Outer surface of

ilium, sacrum,

coccyx,

sacrotuberous

ligament

Iliotibial tract and

gluteal tuberosity

of femur

Inferior gluteal

nerve

L5; S1, 2

Extends and

laterally rotates

hip joint; through

iliotibial tract,

it extends knee

joint

Gluteus medius

Outer surface of

ilium

Lateral surface of

greater trochanter

of femur

Superior

gluteal nerve

L5; S1

Abducts thigh at hip

joint; tilts pelvis

when walking to

permit opposite

leg to clear

ground

Gluteus minimus

Outer surface of

ilium

Anterior surface of

greater trochanter

of femur

Superior gluteal

nerve

L5; S1

Abducts thigh at hip

joint; tilts pelvis

when walking to

permit opposite

leg to clear

ground

latae

Iliac crest

Iliotibial tract

Superior gluteal

nerve

L4; 5

Assists gluteus

maximus in

extending the

knee joint

Piriformis

Anterior surface

of sacrum

Upper border of

greater trochanter

of femur

1st and 2nd

sacral nerves

L5; S1, 2

Lateral rotator of

thigh at hip joint

Obturator

internus

Inner surface

of obturator

membrane

Upper border of

greater trochanter

of femur

Sacral plexus

L5; S1

Lateral rotator of

thigh at hip joint

Gemellus

superior

Spine of ischium

Upper border of

greater trochanter

of femur

Sacral plexus

L5; S1

Lateral rotator of

thigh at hip joint

Gemellus

inferior

Ischial tuberosity

Upper border of

greater trochanter

of femur

Sacral plexus

L5; S1

Lateral rotator of

thigh at hip joint

Quadratus

femoris

Lateral border

of ischial

tuberosity

Quadrate tubercle of

femur

Sacral plexus

L5; S1

Lateral rotator of

thigh at hip joint

The predominant nerve root supply is indicated by boldface type.

448

CHAPTER 10

the vastus lateralis, and overlying the ischial tuberosity.

greater trochanter, between the tendon of insertion and

maximus: between the tendon of insertion and the

Three bursae are usually associated with the gluteus

is inserted into the greater trochanter of the femur.

tendon is joined by the superior and inferior gemelli and

lesser sciatic foramen to enter the gluteal region. The

within the pelvis at its origin. It emerges through the

The obturator internus is a fan-shaped muscle that lies

gluteal vessels and nerves (Fig. 10.15).

the superior gluteal vessels and nerves from the inferior

to enter the gluteal region. Its position serves to separate

its origin. It emerges through the greater sciatic foramen

The piriformis (Fig. 10.15) lies partly within the pelvis at

The Lower Limb

■

ciculi that can be easily separated without damage. The great

Gluteus Maximus and Intramuscular Injections

The gluteus maximus is a large, thick muscle with coarse fas-

thickness of this muscle makes it ideal for intramuscular injec-

tions. To avoid injury to the underlying sciatic nerve, the injec-

tion should be given well forward on the upper outer quadrant
of the buttock.

Gluteus Maximus and Bursitis

Bursitis, or inflammation of a bursa, can be caused by acute

or chronic trauma. An inflamed bursa becomes distended with

excessive amounts of fluid and can be extremely painful. The

bursae associated with the gluteus maximus are prone to

inflammation.

C L I N I C A L N O T E S

seriously interferes with the ability of the patient to tilt the pel

ments of the spinal cord. They are supplied by the superior

Gluteus Medius and Minimus and Poliomyelitis

The gluteus medius and minimus muscles may be paralyzed

when poliomyelitis involves the lower lumbar and sacral seg-

gluteal nerve (L4 and 5 and S1). Paralysis of these muscles

vis when walking.

C L I N I C A L N O T E S

Nerves of the Gluteal Region

pelvic surface.

rator internus supplies the obturator internus muscle on its

supplies structures in the perineum. The nerve to the obtu

in the ischiorectal fossa (see page 309). The pudendal nerve

the pelvis through the lesser sciatic foramen; they then lie

with the internal pudendal artery and immediately re-enter

formis (Figs. 10.14 and 10.15). They cross the ischial spine

lower part of the greater sciatic foramen, below the piri

nerve to the obturator internus leave the pelvis through the

Branches of the sacral plexus, the pudendal nerve, and

Obturator Internus

Pudendal Nerve and the Nerve to the

the quadratus femoris and the inferior gemellus.

greater sciatic foramen (Fig. 10.15). It ends by supplying

femoris leaves the pelvis through the lower part of the

A branch of the sacral plexus, the nerve to the quadratus

Nerve to the Quadratus Femoris

It supplies the gluteus maximus muscle.

atic foramen below the piriformis (Figs. 10.14 and 10.15).

leaves the pelvis through the lower part of the greater sci

The inferior gluteal nerve, a branch of the sacral plexus,

Inferior Gluteal Nerve

both, and ends by supplying the tensor fasciae latae.

ward between the gluteus medius and minimus, supplies

atic foramen above the piriformis (Fig. 10.15). It runs for

leaves the pelvis through the upper part of the greater sci

The superior gluteal nerve, a branch of the sacral plexus,

Superior Gluteal Nerve

upper part of the leg (Fig. 10.1)

to the back of the thigh and the

Cutaneous branches

or labium majus

to the skin of the back of the scrotum

Perineal branch

quadrant of the buttock (Fig. 10.1)

to the skin over the lower medial

Gluteal branches

Branches

thigh beneath the deep fascia. In the popliteal fossa, it sup

surface of the sciatic nerve and runs down the back of the

muscle (Fig. 10.14). It passes downward on the posterior

part of the greater sciatic foramen below the piriformis

sacral plexus, enters the gluteal region through the lower

The posterior cutaneous nerve of the thigh, a branch of the

Posterior Cutaneous Nerve of the Thigh

region.

The sciatic nerve usually gives no branches in the gluteal

region by passing above or through the piriformis muscle.

sciatic nerve high in the pelvis and appears in the gluteal

Occasionally, the common peroneal nerve leaves the

biceps femoris to enter the back of the thigh (see page 466).

the buttock region by passing deep to the long head of the

ous nerve of the thigh and the gluteus maximus. It leaves

(Fig. 10.15). It is related posteriorly to the posterior cutane

femoris to reach the back of the adductor magnus muscle

obturator internus, the inferior gemellus, and the quadratus

on the root of the ischial spine, the superior gemellus, the

cle and curves downward and laterally, lying successively

and 10.17). The nerve appears below the piriformis mus

mon peroneal nerves bound together with fascia (Figs. 10.16

largest nerve in the body and consists of the tibial and com

the greater sciatic foramen (Figs. 10.14 and 10.15). It is the

2, and 3), emerges from the pelvis through the lower part of

The sciatic nerve, a branch of the sacral plexus (L4 and 5; S1,

Sciatic Nerve

plies the skin.

■

-
-

Basic Anatomy

449

L4 L5 S1 S2 S3

sciatic nerve

pelvis

sacral plexus

sciatic nerve

gluteal region

tibial nerve

common peroneal nerve

back of thigh

biceps femoris (short head)

lateral cutaneous nerve of calf

knee joint

lower leg

skin of lateral side of leg

sural

communicating

branch

deep peroneal

nerve

tibialis

extensor

hallucis longus

peroneus tertius

ankle joint

superficial peroneal nerve

peroneus longus

skin of leg

foot

skin of lateral

side of foot

and little toe

extensor

digitorum

brevis

skin of cleft

between first

and second toes

skin of dorsum of foot

extensor digitorum

longus

peroneus brevis

FIGURE 10.16

Summary of the origin of the sciatic nerve and the main branches of the common peroneal nerve.

the first perforating artery, a branch of the profunda artery.

ral circumflex artery, the lateral femoral circumflex artery, and

the anastomosis: the inferior gluteal artery, the medial femo

and the femoral arteries. The following arteries take part in

anastomosis, provides a connection between the internal iliac

trochanter of the femur and, together with the trochanteric

The cruciate anastomosis is situated at the level of the lesser

The Cruciate Anastomosis

circumflex artery, and the lateral femoral circumflex artery.

gluteal artery, the inferior gluteal artery, the medial femoral

following arteries take part in the anastomosis: the superior

along the femoral neck beneath the capsule (Fig. 10.18). The

supply to the head of the femur. The nutrient arteries pass

The trochanteric anastomosis provides the main blood

The Trochanteric Anastomosis

region.

ous branches that are distributed throughout the gluteal

formis (Figs. 10.14 and 10.15). It divides into numer

lower part of the greater sciatic foramen, below the piri

iliac artery and enters the gluteal region through the

The inferior gluteal artery is a branch of the internal

Inferior Gluteal Artery

distributed throughout the gluteal region.

(Figs. 10.14 and 10.15). It divides into branches that are

part of the greater sciatic foramen above the piriformis

iliac artery and enters the gluteal region through the upper

The superior gluteal artery is a branch from the internal

Superior Gluteal Artery

Arteries of the Gluteal Region

-
-

Arterial Anastomoses and Femoral Artery Occlusion

The importance of the trochanteric and cruciate anastomoses

in femoral artery occlusion is discussed on page 524.

C L I N I C A L N O T E S

450

CHAPTER 10

The Lower Limb

sciatic nerve

L4 L5 S1 S2 S3

pelvis

sacral plexus

gluteal region

sciatic nerve

hip joint

tibial nerve

common peroneal nerve

back of thigh

semitendinosus

biceps femoris

(long head)

semimembranosus

adductor magnus

(hamstring part)

lower leg

knee joint

gastrocnemius

soleus

plantaris

popliteus

tibialis posterior

flexor digitorum longus

flexor hallucis longus

skin of ankle

ankle joint

sural nerve

sole of foot

medial plantar nerve

adductor hallucis

flexor digitorum brevis

flexor hallucis brevis

first lumbrical

joints

of foot

skin of sole
of foot

lateral plantar nerve

skin of sole

of foot

flexor digitorum accessorius

abductor digiti minimi

flexor digiti minimi brevis

second, third, fourth lumbricals

abductor hallucis

all interossei

FIGURE 10.17

Summary of the origin of the sciatic nerve and the main branches of the tibial nerve.

a branch of the

lateral cutaneous nerve of the thigh,

The

Cutaneous Nerves

The Front and Medial Aspects

of the Thigh

Skin of the Thigh

lumbar plexus (L2 and 3), enters the thigh behind the lateral

the cremaster muscle (see page 222).

small area of skin (Fig. 10.2). The genital branch supplies

behind the middle of the inguinal ligament and supplies a

branch of the lumbar plexus (L1 and 2), enters the thigh

femoral branch of the genitofemoral nerve,

The

skin of the lower lateral quadrant of the buttock (Fig. 10.1).

the lateral aspect of the thigh and knee. It also supplies the

into anterior and posterior branches, it supplies the skin of

end of the inguinal ligament (Fig. 10.2). Having divided