Chapter 7: The Lower Extremity: The Hip Region KINESIOLOGY Scientific Basis of Human Motion, 11th edition Hamilton, Weimar & Luttgens Presentation Created by TK Koesterer, Ph.D., ATC Humboldt State University Revised by Hamilton & Weimar

Objectives 1. Name, locate, & describe the structure & ligamentous reinforcements of the pelvic girdle and hip joints. 2. Name & demonstrate movements possible. 3. Name & locate muscles & muscle groups, and name their primary actions. 4. Analyze the fundamental movements with respect to joint & muscle actions. 5. Describe common athletic injuries.

THE PELVIC GIRDLE Structure Pelvic bones Illium Ischium Pubis Sacrum Fig 7.1

Movements of the Pelvis Fig 7.4 Midposition Backward Tilt Forward Tilt

Movements of the Pelvis Lateral Tilt Rotation Fig 7.5

Muscles of the Pelvis Forward tilt Backward tilt Lateral Tilt to Right Hip flexors & lumbosacral spinal extensors. Backward tilt Hip extensors & lumbosacral spinal flexors. Lateral Tilt to Right Left lateral lumbosacral flexors, right hip abductors, & left hip adductors. Rotation to Right Left lumbosacral rotators, left hip external rotators, & right hip internal rotators.

RELATIONSHIP OF PELVIS TO TRUNK & LOWER EXTREMITIES Link between the trunk and lower extremities. Must cooperate with motion, yet contribute to stability. Primary movements of pelvis are initiated in the pelvis itself. Secondary movements are associated with motion of trunk or thighs.

Primary Movements of Pelvis Forward tilt Backward tilt Lateral tilt left Rotation left Spinal Joints Hyperextension Slight flexion Slight lateral flexion right Rotation right Hip Joints Slight flexion Complete extension R: Slight adduction L: Slight abduction R: Slight external rotation L: slight internal rotation

Secondary Movements of Pelvis Spine Flexion Hyperextension Lateral flexion left Rotation left Pelvis Backward tilt Forward tilt Lateral tilt left Rotation left

THE HIP JOINT Structure Ball-and-socket joint. Articulation of spherical head of femur with deep cup-shaped acetabulum. Head of femur covered with hyaline cartilage, except fovea capitis. Femoral neck at 126°- 131° angle w/shaft. Femoral neck has slight anteversion. Femoral neck Neck-shaft Angle Fig 7.8

THE HIP JOINT Structure Acetabulum is lined with hyaline cartilage. Acetabular labrum (fibrocartilage) adds depth to joint and serves to cushion against impact of femoral head. Acetabular notch at junction of three pelvic bones. Fig 7.9

Ligamentous Reinforcements Transverse acetabular ligament A strong flat band. Bridges acetabular notch & completes acetabular ring. Fig 7.9

Ligamentous Reinforcements Teres femoris ligament “Ties” head of femur to lower part of acetabulum. Provides reinforcement from within. Fig 7.10

Ligamentous Reinforcements Iliofemoral ligament Extraordinarily strong band. Checks extension & rotation. Pubofemoral ligament Prevents excessive abduction. Fig 7.11

Ligamentous Reinforcements Ischiofemoral ligament Strong triangular ligament. Limits rotation & adduction in the flexed position. Fig 7.12

Movements of the Femur at the Hip Joint Fig 7.13a&b Flexion Extension Hyperextension Abduction Adduction

Movements of the Femur at the Hip Joint Fig 7.13c&d Lateral rotation Medial rotation Diagonal abduction Diagonal Adduction

MUSCLES OF THE HIP JOINT Anterior Iliopsoas Pectineus Rectus femoris Sartorius Tensor fasciae latae Posterior Biceps femoris Semimembranosus Semitendinosus Gluteus maximus Six deep outward rotators Hamstrings

MUSCLES OF THE HIP JOINT Medial Adductor brevis Adductor longus Adductor magnus Gracilis Lateral Gluteus medius Gluteus minimus

MUSCLES OF THE HIP JOINT Iliopsoas Psoas minor & major, & iliacus Function: Strong hip flexor. Pectineus Flexes thigh. Assists in adduction. Fig 7.14

MUSCLES OF THE HIP JOINT Rectus Femoris Function: Flexes thigh at hip. Assists adduction. Sartorius Abducts & externally rotates. Tensor Fasciae Latae Flexes & abducts femur. Tenses fascia lata. Fig 7.15

MUSCLES OF THE HIP JOINT Biceps Femoris Semimembranosus Semitendinosus Function: Extend hip Fig 7.16

MUSCLES OF THE HIP JOINT Gluteus Maximus Function: Powerful hip extensor against resistance. Lower portion assists in adduction. Upper portion abducts against strong resistance. Six Deep Outward Rotators External rotation. Fig 7.19

MUSCLES OF THE HIP JOINT Adductor brevis Function: Adducts & aids in flexion. Adductor Longus Adducts & flexes. Fig 7.21

MUSCLES OF THE HIP JOINT Adductor Magnus Function: Adducts Extends thigh. Lower portion assists internal rotation. Gracilis Adducts & flexes. Fig 7.21

MUSCLES OF THE HIP JOINT Gluteus Medius Function: Abducts Anterior fibers internally rotate. Gluteus Minimus Function: Internal rotation & abduction. Fig 7.22

Muscular Analysis of Fundamental Movements of the Thigh Flexion: tensor fasciae latae, pectineus, iliopsoas, rectus femoris, & sartorius. Extension: Hamstring muscles. Abduction: Gluteus medius & minimus. Adduction: adductor longus is primary, adductor magnus & brevis, and gracilis. Lateral Rotation: Six deep outward rotators, biceps femoris, and gluteus maximus. Medial Rotation: gluteus medius & minimus.

COMMON INJURIES OF THE THIGH, HIP JOINT, AND PELVIS Contusions Results from a direct blow. Pinches muscle between bone and external force. Blow to Iliac crest - “hip pointer”. Myositis ossificans may result.

COMMON INJURIES OF THE THIGH, HIP JOINT, AND PELVIS Myositis Ossifican Calcification following repeated traumas or serious contusions. Improper treatment of contusions. Hamstring Strains Muscular imbalance, fatigue, sudden change in direction or speed. Occurs at myotendinous junctions.

COMMON INJURIES OF THE THIGH, HIP JOINT, AND PELVIS Hip Fracture Usually fractures of femoral neck. Often caused by impact or falls. Hip replacement often the only option.

Chapter 7: The Lower Extremity: The Hip Region