MODULE 7 HIP

HIP: NORMAL ANATOMY AND POSITIONING Three views AP Lateral Frog Leg

LINES OF MENSURATION Teardrop distance Maximum of 11.0mm, minimum of 6.0mm, with an average of 9.0mm Waldenstrom sign

Fig 3-48A Teardrop distance

Fig 3-48A Increased Teardrop distance

LINES OF MENSURATION Hip joint space width Three measurements superior axial medial (aka - teardrop) Pattern of collapse is very important to note

Hip joint space width

LINES OF MENSURATION Acetabular Depth <7.0mm in males and 9.0mm in females Dysplasia has an intact joint space Rheumatoid arthritis has a loss in joint space

Acetabular Depth Fig 3.50a

LINES OF MENSURATION Center-edge angle Represents “coverage” of femur head by acetabulum Minimum of 20o, maximum of 40o, with an average of 36o

Center-edge angle Fig 3.51a

LINES OF MENSURATION Symphysis Pubis Width Increased width is indicative of cleidocranial dysplasia, bladder exostrophy, HPT, trauma - diastasis, osteolysis - ankylosing spondylitis, osteopubis, gout

Symphysis Pubis Width Fig 3.52a

Symphysis Pubis Width Fig 3.52b

LINES OF MENSURATION Acetabulur angle Minimum 12o, maximum 29o, with an average of 20o Increased angle is indicative of dysplasia, congenital hip dislocation Decreased angle is indicative of Down’s syndrome

Acetabulur angle Fig 3.54

LINES OF MENSURATION Protrusio acetabuli (Kohler’s line) Femur head should be lateral If acetabulum floor crosses line - idiopathic, rheumatoid arthritis, Paget’s (osteomalacia)

Kohler’s line Fig 3.57b