The hip joint is a ball and socket joint that connects the femur to the pelvis. It is the body's largest weight bearing joint. The rounded head of the femur fits into the cup-shaped acetabulum of the pelvis. Strong ligaments and muscles provide stability to the joint. Damage to any of the hip joint components can negatively affect its range of motion and weight bearing ability, and may require hip replacement surgery. The hip allows for flexion, extension, abduction, adduction, internal and external rotation.

1. KINESOLOGY OF HIP JOINT
PRESENTED BY :
DR.ASER MOHAMED KAMAL
PHYSICAL THERAPIST

2. Hip joint
The hip is the body’s second largest weight-bearing joint (after the
knee). It is a ball and socket joint at the juncture of the leg and pelvis.
The rounded head of the femur (thighbone) forms the ball, which fits
into the acetabulum (a cup-shaped socket in the pelvis). Ligaments
connect the ball to the socket and usually provide tremendous
stability to the joint. The hip joint is normally very sturdy because of
the fit between the femoral head and acetabulum as well as strong
ligaments and muscles at the joint.
All of the various components of the hip mechanism assist in the
mobility of the joint. Damage to any single component can negatively
affect range of motion and ability to bear weight on the joint.
Orthopedic degeneration or trauma – those conditions affecting the
bones in the hip joint – can necessitate total hip replacement, partial
hip replacement orhip resurfacing.
Bones of the hip joint
The femur is the upper leg bone or thigh. It is the largest bone in the
body. At the top of the femur is a rounded protrusion which
articulates with the pelvis. This portion is referred to as the head of
the femur, or femoral head.
There are two other protrusions near the top of the femur, known as
the greater and lesser trochanters. The muscles involved in hip
motion are attached to the joint at these trochanters.

3. The acetabulum is a concave area in the pelvis, into which the
femoral head fits. The pelvis is a girdle of bones, connected at the
front by cartilage pad, called the pubis, and at the back by the lowest
four fused vertebrae (the sacrum). The sacro-iliac joints are located
where the sacrum meets the pelvis.
The bone surfaces of the femoral head and acetabulum have a
smooth durable layer of articular cartilage that cushions the ends of
the bones and allows for smooth movement.
Pelvis
o 1/5 pubis
o 2/5 ischium
o 2/5 ilium
o Pelvis full ossification = 15-25 y.o.
Acetabulum
o Concave socket
o Lateral, inferior, anterior (LIA)
o Roundness ↓ w/ age
o Inferior = acetabular notch
o Central/deepest part = acetabular fossa
o Anteversion = anterior orientation of acetabulum
 Men = 18.50
 Women = 21.5 0
 Pathologic ↑ = ↓ jt. stability, risk for anterior
dislocation of femoral head
Femur
o Circular
o Smaller in women
o Fovea
 Inferior to medial pt. of femoral head
 Attachment of ligament of femoral
head

4. o Medially, superiorly, anteriorly (SAM)
o Neck = 5cm long
o Angulation
 Angle of inclination (medial)
 Frontal plane bet. Femoral neck & shaft
 Early infancy = 1500
 Adult = 1250
 Elderly = 1200
 ↓ in women due to width of female pelvis
 Pathologic ↑ = coxa valga
 Pathologic ↓ = coxa vara
 Angle of torsion
 Transverse plane bet. Femoral neck &
condyles
 Anterior torsion =relative lateral
rotation
 ↓ w/age
 Newborn = 400
 Adult = 150
 Anteversion
o Pathologic ↑
o Internal femoral torsion
o ↓ ER
o ↑ IR
 Retroversion
o Pathologic ↓
o External femoral torsion
o Frog-leg position
 FABER
 True physiologic position of hip
o A congruent fit under low load would lead to
incongruence under high load
o Periphery of acetabulum in contact, fossa is non-articular

5. Bony landmarks:
Femur:
1. Greater trochanger – lateral aspect of thigh just
distal to hip joint.
2. Medial and lateral condyles– on distal end of femur
3. Medial and lateral epicondyles (Epicondyles)
Patella:
“Knee cap” – anterior aspect of knee (a sesamoid bone
located in quadriceps tendon).
HIP JOINT
› ROM
o Flex 0-1200
o Hypertext 0-100
o Abd 0-450
o Add across30-400
o ER 0-450
o IR 0-350
› Close-packed
o Full ext, IR, Abd
› Open-packed
o 300
flex
o 300
abd
o Slight ER
› Capsular pattern
o Flex, abd, IR
› End feel
o Flex soft/firm
o Ext firm
o Abd soft/firm
o Add soft/firm
o IR firm
o ER firm
› End Feels
› Normal:
o Flexion & Adduction
 Elastic or Tissue Approximation

6. o SLR
 Elastic
o Extension & Abduction
 Elastic/Firm
› IR & ER
 Elastic/Firm
› Tonic labyrinthine & optical righting reflexes
o Head effectively behaves as if it’s fixed in a
vertical position
o Maintains head over BOS
› When hip flexor ms. Is tight, keep LOG w/in BOS
o Open-chain response = displacement of
head from vertical (Fig. A)
o Closed-chain response = maintain head in
upright position (Fig. B)
› Acetabulum of pelvis + head of femur
› Diarthrodial, ball-and-socket jt. w/ 30
freedom:
o flex/ext in sagittal plane
o abd/add in frontal plane
o IR/ER in transverse plane
› 10
function of hip
o To support wt. of head, arms & trunk (HAT)
› Also provides pathway for transmission of forces bet. Pelvis & LEs
› Hip tends to operate in a closed kinematic chain
o Proximal end = head
o Distal end = foot
Hip joint capsule or socket
You may hear your hip
surgeon refer to the capsule
or socket, when describing
the structure of the hip joint.
The joint capsule is a thick
ligamentous structure
surrounding the entire joint.
Inside the capsule, the surfaces of the hip joint are covered by a thin
tissue called the synovial membrane. This membrane nourishes and
lubricates the joint.

7. o capsule has major contribution to stability
o femoral neck = intracapsular
o greater & lesser trochanters = extracapsular
o thickened anterosuperiorly
o thin & loose posteroinferiorly
Ligaments
As noted above, the stability of the hip joint is
directly related to its muscles and ligaments. The
most notable ligaments in the hip joint are:
 Iliofemoral ligament, which connects the pelvis
to the femur at the front of the joint. It keeps the
hip from hyper-extension
o Iliofemoral ligament
 Y ligament of Bigelow
 Origin = AIIS
 2 arms fan out to insert =
intertrochanteric line of femur
 Strongest ligament of hip
 Taut in hyperextension
 Superior fibers taut in adduction
 Inferior tense during abduction
 Pubofemoral ligament, which attaches the most forward part of
the pelvis known as the pubis to the femur
 Origin = anterior pubic ramus
 Insertion = anterior intertrochanteric fossa
 Taut in hip abd & ext

8.  Ischiofemoral ligament, which attaches to the
ischium (the lowest part of the pelvis) and between
the two trochanters of the femur.
 Origin = posterior acetabular rim,
acetabulum labrum
 Insertion = spiral around femoral neck
 Spiral fibers taut during ext, loosen in
flex
o Position of stability
 Full extension of hip
o Position of vulnerability
 Flex & add (such as sitting w/thighs
crossed)
 Ligamentum teres
 Triangular
 Ligament of head of femur
Labrum
The labrum is a circular layer of cartilage which surrounds the outer
part of the acetabulum effectively making the socket deeper to
provide more stability for the joint. Labrum tears are not an
uncommon hip injury.
o Acetabular labrum
 Fibrocartilage rimming entire periphery
o Transverse acetabular ligament
 Roof of tunnel passage for blood vessels & nerves
entering hip
o Has Center Edge angle (CE) or angle of Wiberg
 Men = 380
 Women = 350
 Smaller CE angle (more vertical) = ↓ coverage of
head of femur, ↑ risk superior dislocation of femoral
head
 ↑ w/age

9. Arthrokinematics
o Movement of convex femoral head on concave
acetabulum
 Femoral head glides opposite motion of distal
femur
 Flex = Head spins posterior
 Ext = anterior spin
o When wt. bearing
 Femur fixed, concave acetabulum moves over
convex femoral head
 Acetabulum glides in same direction
Hip Mobilization
 Flexion: Femur rolls superior & glides inferiorly on pelvis
 Extension: Femur rolls inferior & glides superior on pelvis
 Abduction: Femur rolls lateral/superior & glides inferior on
pelvis
 Adduction: Femur rolls medial/inferior & glides superior on
pelvis
 Internal Rotation: Femur rolls medial & glides lateral on
pelvis
 External Rotation: Femur rolls lateral & glides medial on
pelvis
Osteokinematics
o Flexion = 900
w/ knee extended
o Normal gait on level ground requires
 300
hip flexion
 100
hyperextension
 50
abd/add/IR/ER
o Anterior pelvic tilt
 Sagittal plane
 Hip flexion
 ASIS anteriorly & inferiorly, symphisis down
o Posterior pelvic tilt
 Hip extension
 Symphisis pubis up
 Posterior pelvis closer to femur

10. o Lateral pelvic tilt
 Frontal plane
 One hip joint serves as pivot/axis
 Opposite iliac crest elevates (hip hike) or drop
(pelvic drop)
 Reference is side farthest from supporting hip
o Pelvic rotation
 Transverse plane
 Occurs in single-limb support around axis of
supporting hip jt.
 Forward rotation
 Side opposite supporting hip moves
anteriorly
 Backward rotation
 Side opposite supporting hip moves
posteriorly
o Lumbar-Pelvic Rhythm
 Open-chain
 E.g. reaching the floor
 Hip flexion up to 900
only
 Anterior tilt of pelvis on femurs
 Flexion of lumbar spine adds 450
 E.g. side-lying abduction
 Lateral tilt of pelvis & lumbar spine adds
450
o Closed chain response to motions of pelvis
 Keeps one or both feet on the ground
 Maintain head upright & vertical
 Anterior pelvic tilt during hip flexion = head &
trunk displaced forward + lumbar extension
 Posterior pelvic tilt + lumbar flexion to keep head
forward over sacrum

11. pelvic motion co-hip motion
compensatory
lumbar
anterior tilt hip flex lumbar ext
posterior tilt hip ext lumbar flex
lateral tilt (drop) right hip add right lateral flex
lateral tilt (hike) right hip abd left lateral flex
forward rot right hip IR rotation to left
backward rot right hip ER rotation to right
Muscle Groups
The muscles of the hip consist of four main
groups
1. Gluteal group: The gluteals are the
muscles in your buttocks. The gluteal muscles
include the gluteus maximus, gluteus
medius, gluteus minimus, and tensor fasciae
latae. They cover the lateral surface of
the ilium.

12. 2. Adductor group: The adductor brevis, adductor
longus, adductor magnus, pectineus, and gracilis make up
the adductor group.
3. Iliopsoas group: The iliacus and psoas major comprise
the iliopsoas group.
4. Lateral rotator group: This group consists of
the externus and internus obturators, the piriformis,
the superior and inferior gemelli, and the quadratus femoris.
5. Other hip muscles: Additional muscles, such as
the rectus femoris and the sartorius, can cause some
movement in the hip joint. However these muscles primarily
move the knee, and not generally classified as muscles of
the hip.
*The hamstring muscles, which originates mostly from the ischial
tuberosity inserting on the tibia/fibula, has a large moment
assisting with hip extension.
Gluteus maximus
 Origin Gluteal surface of ilium, lumbar
fascia, sacrum, sacrotuberous ligament
 Insertion Gluteal tuberosity of the
femur and iliotibial tract
 Nerve Inferior gluteal nerve (L5, S1 and
S2 nerve roots)
 ACTION Extends and laterally rotates
hip. Maintains knee extended via
iliotibial tract
Gluteus Medius
 Origin: Outer surface of the ilium, between the iliac crest and
the posterior gluteal line above and the anterior gluteal line
below.
 Insertion: Posterolateral surface of the greater trochanter of
the femur.
 Action: Abduction of the hip, internal rotation of thigh.
 Innervation: Superior gluteal nerve L4, 5, S1).

13. Gluteus Minimus
 Origin: Outer surface of the ilium, between the anterior and
inferior gluteal lines, and the edge of the greater sciatic notch.
 Insertion: Anterior surface of the greater trochanter of the
femur.
 Action: Abduction of the thigh, internal rotation of thigh.
 Innervation: Superior gluteal nerve L4, 5, S1).
Tensor Fasciae Latae
 Origin: Outer surface of the anterior iliac crest, between the
tubercle of the iliac spine. A thick fascia covers the outer surface of
the muscle, making it appear to be sandwiched between the layers
of fasciae latae.
 Insertion: By the iliotibial band anterior surface of the lateral
condyle of the tibia.
 Action: Assists with flexion of the thigh at the hip, assists with
adduction of the thigh at the hip
 Innervation: Superior gluteal nerve (4 -5, S1)
Adductor Magnus Muscle
 Origin:
Anterior: Inferior pubic ramus and the ramus of the ischium
Posterior: Inferolateral aspect of the ischial tuberosity
 Insertion:
Anterior: Medial margin of the gluteal tuberosity of the femur,
medial to gluteus maximus.
Posterior: By a broad attachment into the linea aspera and the
proximal part of the medial supracondylar line and by a small
tendon to the adductor tubercle.
 Action: Adduction of the thigh at the hip, extension of the
thigh at the hip
 Innervation: Posterior division of the obturator nerve (L2 – 4)
Adductor Longus
 Origin: Anterior surface of the pubis, in the angle between the
crest and pubic symphysis.
Insertion: Lower two-thirds of the medial lip of the linea aspera
on the posterior surface.
 Action: Adduction of the thigh at the hip, assists with internal
rotation of the thigh at the hip, assists with flexion of the thigh at
the hip

14.  Innervation: Anterior division of the obturator nerve (L2 -3)
Adductor Brevis
 Origin: Inferior ramus and body of the pubis, between gracilis and
obturator externus.
 Insertion: Along a line from the lesser trochanter to the linea
aspera, the upper third of the linea aspera, downward along the
upper third of the linea aspera, immediately behind the pectineus
and the upper part of adductor longus
 Action: Adduction of the thigh at the hip, assists with internal
rotation of the thigh at the hip.
 Innervation: Anterior division of the obturator nerve (L2 -3)
Pectineus
 Origin: Pectineal line of the pubis and a narrow area of the superior
pubic ramus below it.
 Insertion: A vertical line from the lesser trochanter to the linea
aspera
 Action: Assists with flexion of the thigh at the hip, assists with
adduction of the thigh at the hip
 Innervation: Anterior division of the femoral nerve (L2 – 3)
Gracilis
 Origin: Lower half of the body of the pubis, the inferior
pubic ramus, and the adjoining part of the ischial ramus.
 Insertion: Upper part of the medial flare of the tibia, just
below the medial condyle, proximal and slightly anterior to
the attachment of the semitendinosus, and posterior and
somewhat inferior to the attachment of sartorius.
 Action: Adduction of the thigh at the hip, assists with
internal rotation of the thigh at the hip, assists with flexion
of the thigh at the hip
 Innervation: Anterior division of the obturator nerve (L2
– 3)

15. Iliacus
 Origin: Superior two-thirds of the
internal surface of the iliac fossa, the
inner lip of the iliac crest, the ventral
surface of the sacroiliac and iliolumbar
ligaments, and the upper surface of the
lateral part of the sacrum.
 Insertion: The lesser trochanter of the
femur after being joined by the tendon
of psoas major. The conjoined tendon
passes under the inguinal ligament to
enter the thigh
 Action: Flexion of thigh at hip, assists in extension of the lumbar spine
 Innervation: Femoral nerve (L2, 3)
Primary Actions of the Iliacus:
1. Flexion of thigh at the hip
2. Flexion of the pelvis at the hip
Psoas Major
 Origin: Anterior surfaces of the transverse processes of T12-L5
vertebrae, the upper two thirds of the iliacus
 Insertion: The lesser trochanter of the femur after being joined by the
iliacus
 Action: Flexion of thigh at hip, assists in extension of the lumbar spine
 Innervation: Lumbar plexus (L2, 3, 4)
Primary Actions of the Psoas Major:
1. Flexion of thigh at the hip
Secondary Actions of the Psoas Major:
2. Assists with extension of the lumbar spine
3. Lateral Flexion of the spine when acting unilaterally

16. Piriformis
 Origin: Anterior surfaces of the sacrum by three or four
slips off the portions of bone between the foramina of the
sacrum, the ilium near the posterior inferior iliac spine, the
capsule of the sacro-iliac joint, and occasionally the upper
part of the sacrotuberous ligament.
 Insertion: By a rounded tendon to the upper part of the
medial surface of the greater trochanter, occasionally
blending with the common tendon of obturator internus,
gemellus superior, and gemellus inferior.
 Action: Assists with lateral rotation and abduction of the thigh
 Innervation: Nerve to piriformis (S1, 2)
Sartorius
 Origin: Inferior portion of the anterior
superior iliac spine
 Insertion: Upper medial surface of tibial
shaft at the tibial flare
 Action: Assists with hip flexion, knee flexion,
medial rotation of the knee, lateral rotation
of the hip
 Innervation: Anterior division of the femoral
nerve (L3- 4)