HIP Joint
• The hip joint is the articulation between
the femur and the acetabulum of the pelvis
and its primary function is to support the
weight of the body in both static (e.g.
standing) and dynamic (e.g. walking or
running) postures
• Seven different kinds of movements
are possible in the hip joint:
• Flexion and extension
• Abduction and adduction
• Internal (medial) and external (lateral)
rotation
• Circumduction
• A synovial joint that can produce
movement in more than one axis is called
a multiaxial joint
• The large head of the femur is completely
covered in hyaline cartilage except for a small
area called the fovea or pit. This is the site of
attachment for an intracapsular ligament
[ligament of head of femur] that attaches directly
from the head of the femur to the acetabulum.
• There is also a small ligament called ligamentum
teres or the ligament of the head of the femur.
This structure is not that important as a ligament
but can often be vitally important as a conduit of
a small artery to the head of the femur. This
arterial branch is not present in everyone but
can become the only blood supply to the bone in
the head of the femur when the neck of the
femur is fractured or disrupted by injury in
childhood.
Ligaments
• At the front of the joint, the strong iliofemoral ligament
attaches from the pelvis to femur. This Y-shaped
ligament is also known as the ligament of Bigelow. This
ligament seeks to resist excessive extension of the hip
joint. It is often considered to be the strongest ligament
in the human body.
• The pubofemoral ligament attaches across the front of
the joint from the pubis bone of the pelvis to the femur.
This ligament is orientated more inferiorly than the
iliofemoral ligament and reinforces the inferior part of the
hip joint capsule. It also blends with the medial parts of
the iliofemoral ligamemt.
• The posterior of the hip joint capsule is reinforced by the
ischiofemoral ligament that attaches from the ischial part
of the acetabular rim to the femur.
Labrum
Though not actually a ligament,
the acetabular labrum (latin for
“lip”) contributes to the stability
of the hip joint by encompassing
more than half of the femoral
head. Together with the
transverse acetabular ligament,
it creates a deep spherical
"cup".
Muscles producing movements
at the hip joint
• The 17 muscles that cause movement in the hip
can be divided into four groups according to
their orientation around the hip joint: the gluteal
group, the lateral rotator group, the adductor
group, and the iliopsoas group. These muscles
produce flexion, extension, lateral rotation,
medial rotation, abduction and adduction.
• Many of the hip muscles are responsible for
more than one type of movement in the hip, as
different areas of the muscle act on tendons in
different ways.
Gluteal group
• The gluteal muscles include the gluteus: maximus,
medius & minimus, and tensor fasciae latae. They cover
the lateral surface of the ilium.
• The gluteus maximus, which forms most of the muscle of
the buttock, originates primarily on the ilium and sacrum
and inserts on the gluteal tuberosity of the femur as well
as the iliotibial tract, a strong fibrous tissue that runs
along the lateral thigh to the tibia & fibula.
• The gluteus medius and gluteus minimus originate
anterior to the gluteus maximus on the ilium and both
insert on the greater trochanter of the femur.
• The tensor fasciae latae shares its insertion with the
gluteus maximus at the ilium and also shares the
insertion at the iliotibial tract.
Adductor group
• The adductor brevis, adductor longus,
adductor magnus, pectineus, and gracilis
make up the adductor group. The
adductors all orginate on the pubis and
insert on the medial, posterior surface of
the femur, with the exception of the gracilis
which inserts just below the medial
condyle of the tibia.
Iliopsoas group
• The iliacus and psoas major comprise the
iliopsoas group. The iliopsoas is a large
muscle that runs from the transverse
processes of the T-12 to L-5 vertebrae,
joins with the iliacus via its tendon, and
connects to the lesser trochanter of the
femur. The iliacus originates on the iliac
fossa of the ilium. Together these muscles
are commonly referred to as the
"iliopsoas".
Lateral rotator group
• This group consists of the externus and
internus obturators, the piriformis, the
superior and inferior gemelli, and the
quadratus femoris. These six originate at
or below the acetabulum of the ilium and
insert on or near the greater trochanter of
the femur.