The Hip: Osteokinematic, Arthrokinematic and Biomechanical Insights Flashcards
The hip has ___ degrees of freedom
3
What ligaments strengthen the hip?
iliofemoral, pubiofemoral, ischiofemoral
What are the characteristics of the male pelvis?
greater pelvis height, less wide; well defined muscle attachments; long and narrow sacrum; heart-shaped pelvis inlet; acetabulum is large
What are the characteristics of the female pelvis?
wider and shorter; indistinct muscle attachments; pelvic inlet is oval; iliolumbar ligament more extensive –> more stable at L5-S1
What ligaments provide more mobility for the hip?
Sacrotuberous and sacrospinous
Whats does the iliofemoral ligament do?
prevents hyperextension
What does the pubofemoral ligament do?
limits excessive extension and abduction
Hip flexion/extension is what plane of motion?
saggital
Hip flexion has slight ______ glide of femoral head on acetabulum
posterior
Hip extension has slight _______ glide of femoral head on acetabulum
anterior
What are closed chain motions?
motions working multiple joints with a constant, fixed position –> deep squat, cycling, pull ups
Hip abduction is what plane of motion?
frontal
Hip abduction has _____ glide of femoral head on the acetabulum
inferior
What are the most common MOIs of the hip?
Hyperflexion, Osseus Failure, Flexion-rotation, Axial Rotation/Extension, Excessive Loading, Repetitive Stress
Internal/external rotation of the hip is on what plane of motion?
Transverse
Hip internal rotation has _____ glide of the femoral head while hip external rotation has _____ glide
posterior; anterior
The position of maximum congruency of the hip consists of …
90 degrees of hip flexion and external rotation
What is the closed-packed position of the hip?
maximum extension, abduction, internal rotation
Where is the coverage of the femoral head the least?
Anatomical position
Where is the coverage of the femoral head the most?
flexion, abduction, and external rotation
What type of chain is the hip joint’s primary function?
closed-chain
What is ligamentum teres?
The ligament of the head of the femur; tubular sheath of synovial lined connective tissue that functions as protective sheath for the acetabular artery
What is the center edge angle?
The amount of the femoral head that is covered by the acetabulum; the LARGER the center edge angle the more stability
What deepens the acetabular socket?
The acetabular labrum (non weight-bearing)
What occurs when the femurs angle of inclination is less than 120 degrees?
coxa vara (closing angle)
____ occurs when the femurs angle of inclination is more than 120 degrees
coxa valga (opening angle)
What is the normal angle of torsion?
20 degrees
What is a femoral angle of torsion greater than 20 degrees known as?
anteversion (opening angle), results in a toed-in gait; compensation at knee
What is a femoral angle of torsion lesser than 20 degrees known as?
retroversion (closing angle), results in a toed out gait
What is the zone of weakness?
area where the trabeculae do not cross right angles, resulting in less reinforcement which leads to more potential for injury
The force of gravity and ground reaction produce a ______ force on the shaft of the femur
bending
What is the strongest hip flexor?
illiopsoas
What are the primary hip flexors in the body? (anterior group)
illiopsoas, pectinous, rectus femoris, and sartorius
What are the hip extensors of the body? (posterior)
gluteus maximus, biceps femoris, semitendinous, semimembranosus, and external rotators
What are the hip abductors of the body? (lateral)
gluteus medius, gluteus minimus, TFL, and external rotators
What are the hip adductors of the body? (medial)
adductor brevis, longus, and magnus and gracilis
What is the lumbar plexus?
formed by anterior rami of spinal nerves L1 through L4 and some fibers from T12
What is the sacral plexus?
formed by anterior rami of L4, L5, S1 through S4
What is the sciatic nerve?
goes under piriformis and up to sciatic notch
