Hip Joint Complex

The Coxofemoral joint is what type of joint

Ball and socket

What DOF does the coxofemoral joint have

3 degrees of freedoms

• Sagittal plane: Flexion/Extension

• Frontal plane: abduction/adduction

• Transverse plane: medial/lateral rotation

What is the acetabulum

The socket of the hip joint

The acetabulum is covered with

Articular cartilage that thickens peripherally

The acetabulum faces which ways?

Anteriorly, laterally, and inferiorly

The Acetabulum is thickened by what?

Labrum

What is the femur

Ball side of the joint

The neck of the femur angulates which ways

Superiorly, anteriorly, and medially

Nutation is caused by

Lumber extension

Counternutation is caused by

Lumbar Flexion

What is strain

Amount of deformation with respect to the structure

What is stress

Distribution of force within a body quantified as force divided by the area over which the force acts

What is bending

asymmetric loading that produces tension on one side of a body’s longitudinal axis and compression on the other side

What is a common injury with bending

Greenstick fracture

What is Wolff’s Law

Adaption to stress over time

How do bones adapt to loads

Mediated via cellular activity

• Osteocytes detect strain damaged bone direct bone remodeling activity

• Osteoblast deposits new bone

• Osteoclast resorb bone

What does A represent

Internal structure on the superior aspect of the acetabulum

What does F represent

Refers to vertical lines passing through the ischium

Example being sitting

What does G represent

Refers to the curved lines along the pubic ramus

What does A represent

Medial compressive system

What does B represent

Lateral tensile system

What does C represent

Zone of weakness

What does F represent

Trochanter System

What is stability

Ability to resist dislocation

What are factors that influence stability

• Shape and congruence of bones

• Supporting structures

What is the hip joint capsule

Strong dense and therefore a significant contributor of the hip joint

What are the attachments of the hip joint capsule

• Periphery of acetabulum

• Base of femoral neck

What are the fibers of the joint capsule

• Circular (zone orbicularis)

• Retinacular Fibers (carry blood Vessels)

What does A represent

Ischiofemoral

What does B represent

Illiofemoral

What does C represent

Pubofemoral

What is special about ischiofemoral ligament

taught in hip extension

What is special about iliofemoral ligament

fan shaped ligament, resembles inverted Y, strongest ligament at the hip. Checks hyperextension

What is special about pubofemoral ligament

taught in hip abduction and in extension. With the iliofemoral ligament it forms a Z on the anterior capsule

What are the functions of the Ligamentum teres

• Secondary stabilizer preventing dislocation

• Conduit for blood supply

• Contains innervation for pain sensation

What movements cause max bony congruence

• Flexion, abduction, and external rotation (frog legged position)

  • Not position of highest stability

What movements cause for most stable position

• Extension, slight abduction, internal rotation

In most stable position how does extension affect ligaments

Further tightens, capsular ligaments

What movements cause for the least stable position

Flexion with adduction

Explain the Center edge angle

• Also called Angle of Wiberg

• Is the angle between vertical and a line drawn from center of femoral head to bony edge of the acetabulum

What is inclination angle

Neck to shaft angle- Superior inferior inclination

What is angle of anteversion

Anterior posterior angulation

Anteversion is often observed with

Coxa Valga

Where is the toe in gait if a person has retroversion

toe out gait

What is closed chain exercise

where the distal end of the limb is fixed to an immovable surface (ex squat or pushup)

What is open chain exercise

involve movement of the distal end of the limb (leg extension or bicep curl)

What is motion of posterior tilt

brings pubis up; leads to hip extension and lumbar flexion

What is motion of anterior tilt

brings anterior superior iliac spine anterior and inferior; leads to hip flexion and lumbar extension

If the right side of the pelvis drops (right hip drop) what are the motions of the right and left hip as well as the spine.

Right hip- abducts

Left hip- adducts

Spine- left lateral flexion

What is pelvifemoral rhythm

To maximize the apparent range of motion of the distal segment multiple joints are used in concert.

Explain lateral trunk lean

Lean toward the side of pain or weakness will reduce the moment arm of the gravitational force. Brings Center of mass closer to hip joint, so less counter torque needed by abductor muscles

When a cane is used contralaterally what are the benefits

• Reduces weight of HAT, but also provides a counter torque to the torque of gravity thus reducing need for abductor muscle force

  • Canes considered to relieve hip of up to 60% of its load in stance

When is used ipsilaterally what is the benefit

• Some benefit from alleviating some of the body weight through the cane

Define osteokinematics

Refers to bone movements of the joint about axes of rotation

Define arthrokinematics

Refers to the movement at the articulating surfaces of the joint

In flexion at hip what is the primary muscle

Iliopsosas

In flexion at the hip what are the secondary muscles used

• Rectus femoris

• Tensor fascia Latae

• Sartorius

In extension at the hip what is the primary muscle

Gluteus maximus

In extension at the hip what are the secondary muscles

• Semitendinosus

• Semimembranosus

• Biceps femoris, long head

abduction at 45-50 degrees is limited by what muscle

Gracilis

Adduction at 20-30 degrees is limited by what muscle

Tensor fascia Latae

What are the arthrokinematics during adduction

Inferior roll and superior gliding

What are the arthrokinematics during abduction

superior roll and inferior gliding

What is the primary muscle use when the hip is abducting

Gluteus Medius

What are the secondary muscles used when the hip is abducting

Gluteus Minimus and Tensor fascia latae

When the hip is adducting what is the primary muscle

Adductor magnus

When the hip is adducting what are the secondary muscles

• Pectineus

• adductor longus

• Adductor brevis

• Gracilis

• Obturator externus

What are the arthrokinematics during medial rotation

Anterior roll and posterior gliding

What are the arthrokinematics during lateral rotation

posterior roll and anterior gliding

During lateral rotation at the hip what are the primary muscles

• Gluteus maximus

• Piriformis

During lateral rotation what are the secondary muscles

• quadratus femoris

• Obturator internus and externus

• Gemellus superior and inferior

• sartorius

What are the short external rotators of the hip

• Piriformis

• Quadratus femoris

• Obturator Internus and externus

• Gemellus superior and inferior

During medial rotation is what are the primary muscles

There is not

During medial rotation what are the secondary muscles

• Tensor fascia Latae

• Gluteus minimus

• Gluteus Medius