MOB TCD

Hip Joint

Professor Emeritus Moira O’Brien

FRCPI, FFSEM, FFSEM (UK), FTCD

Trinity College

Dublin

Hip Joint

• Synovial ball and socket joint

• Multiaxial• Three degrees of freedom• Movement in three planes• Close pack extension and

medial rotation• Least pack semiflexion

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• One of most stable joints in the body

• Articular surface of hip joint are reciprocally curved

• Superior surface of femur and acetabulum sustain greatest pressure

Hip Joint MOB TCD

Acetabulum

• Y-shaped epiphyseal cartilage• Start to ossify at 12 years• Fuse 16-17 years• Acetabular notch is inferior• Nonarticular fossa, thin related

medially to obturator internus• Pad of fat, proprioceptive nerves

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Articular Surface of Hip Joint

• Semilunar articular surface covered with hyaline cartilage

• Deepened by acetabular labrum

• Wedge shaped fibrocartilage

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• Head of femur 2/3rd of sphere• Pit for ligamentum teres• Covered with articular cartilage• Cartilage thicker posterior superior• Epiphyseal line for head

intracapsular

Articular Surface MOB TCD

Femur

• Trabeculae develop along lines of stress

• Calcar femorale is the cortical bone on inferior aspect of neck

• Neck is cancellous bone

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Capsule of Hip

• Proximally attached• Margins of the acetabular

fossa • Base of labrum• Distally, anterior to the

intertrochanteric line• Inferiorly, femoral neck close

to lesser trochanter

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• Posterior• Free border, finger’s breath

from trochanteric crest due to insertion of obturator externus

• Into trochanteric fossa and• Root greater trochanter

Capsule of Hip MOB TCD

• Strongest superiorly• Anteromedially, deep fibres

reflected head of rectus femoris

• Iliopsoas is anterior• Lateral deep fibres of gluteus

minimus

Capsule of Hip MOB TCD

Retinacular Fibres

• Fibres of capsule reflected along neck to articular margin called retinacular fibres

• Blood supply to head run under retinacular fibres

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Ligaments of Hip

• Acetabular labrum• Transverse ligament• Ligament of head• Iliofemoral ligament• Pubofemoral ligaments• Ischiofemoral ligaments• Zona orbicularis

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• Transverse ligament is part of the labrum

• Ligamentum teres is triangular, its base is attached to transverse ligament, and the apex to the pit on the head of femur

• Blood supply to epiphysis from obturator artery

• Only supplies a flake of bone in elderly

Ligaments of Hip MOB TCD

Iliofemoral Ligament

• Thickening of capsule• Lower half of anterior

inferior iliac spine and adjoining acetabulum

• Distally• Upper and lower parts of

inter trochanteric line

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• One of strongest ligaments in body

• Tightens in extension• Helps maintain erect

posture• Facet on anterior aspect

of neck• Prevents hyperextension • Fulcrum reducing hip

Iliofemoral Ligament MOB TCD

Pubofemoral Ligament

• Superior pubic ramus• Inferior part of inter

trochanteric line and upturned part

• Relatively weak• Prevents abduction• Bursa between it and

iliofemoral

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Ischiofemoral Ligament

• Ischium to posterior part of joint (weak)

• Circular fibres called zona orbicularis

• Centre of gravity in front of head

• Synovial under obturator externus

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Synovial Membrane

• Lines inner portion of capsule and non articular structures

• Ligament of head• Fat in acetabular fossa• May communicate with psoas

bursa • Bursa under obturator

externus

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Bursa Under Gluteus Maximus

• Trochanteric bursa• Posterolateral aspect of

greater trochanter gluteofemoral

• Vastus lateralis ischial bursa• Ischial tuberosity

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Blood Supply to Head of Femur

• Child, obturator artery via ligamentum teres supplies epiphysis

• Elderly, main supply via retinacular vessels from trochanteric and cruciate anastamoses

• Medial and lateral circumflex femoral vessels

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Blood Supply

• Superior gluteal supplies the upper part of the acetabulum

• Inferior gluteal supplies the inferior and posterior and the capsule

• Transverse and ascending branches of lateral circumflex femoral artery

• Transverse and ascending branch of medial circumflex femoral

• Cruciate and trochanteric anastomosis

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• Fractures of neck may cause avascular necrosis, extra capsular arteries enter the trochanter at the base of neck

• Medial and lateral circumflex femoral vessels and superior gluteal

Blood Supply MOB TCD

• Femoral nerve• Obturator nerve• Superior gluteal nerve• Nerve to quadratus femoris• Posterior dislocation may

damage sciatic• Pain in hip referred to knee

Nerve Supply MOB TCD

Anterior Relations

• Rectus femoris• Adductor longus • Pectineus• Psoas and iliacus• Femoral sheath• Femoral nerve

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Inferior and Posterior Relations

• Obturator externus• Passes inferior and then posterior

to joint • Superior gluteal nerve• Inferior gluteal nerve• Sciatic nerve• Posterior cutaneous nerve thigh• Nerves to obturator internus and

quadratus femoris• Pudendal nerve

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Lateral Relations

• Gluteus minimus • Gluteus medius• Superior gluteal vessels and

nerves between• Iliotibial tract• Superficial three quarters of

gluteus maximus

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Posterior Relations

• Piriformis • Superior gemellus• Obturator internus• Inferior gemellus• Quadratus femoris• Adductor magnus• Obturator externus• Gluteus maximus

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Movements: Flexion

• Limited by anterior abdominal wall

• Psoas• Iliacus• Pectineus• Adductor longus and brevis• Rectus femoris

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Movements: Extension

• Hamstrings first 10°• Long head of biceps• Semitendinosus• Semimembranosus

• 123, extended knee ++• Adductor magnus• Gluteus maximus most efficient when hip is

flexed 45°

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• Obturator nerve• Adductor longus• Adductor brevis• Adductor magnus• Can flex or extend depending

on position of hip

Movements: Adduction MOB TCD

• Gluteus medius• Gluteus minimus• Standing on leg, gluteus medius and

minimus abduction

• By preventing adduction

Movements: Abduction MOB TCD

• Iliopsoas • Adductors• Anterior fibres of gluteus medius

Movements: Medial Rotation MOB TCD

• Obturator internus• Piriformis• Superior gemmelus• Obturator Internus • Inferior gemmelus• Quadratus femoris

Movements: Lateral Rotation MOB TCD

Trendelenburg Tests MOB TCD

Fractured Neck of Femur MOB TCD

Hip Problems in Children

• Apophysitis • Avulsion fractures• After 13 years• 11-40% of all hip and pelvic fracturesBoyd et al., 1997

• Anterior superior iliac spine• Anterior inferior iliac spine• Ischial tuberosity commonest

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Hip Problems MOB TCD

Pain in a Child

• 5-10 year old child• Aching pain in hip• Limp• Limitation of movement• Perthe’s• Osteochondritis of head of femur

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Stability of Hip

• One of the most stable joints• Congenital dislocations is

common• 1.5 per 1000 live births• Female : male = 8:1 • Ultrasound best method of

detecting

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Femoral Anteversion

• Femoral version is the angular difference between axis of femoral neck and transcondylar axis of the knee

• Femoral anteversion ranges from 30 º - 40 º at birth • Decreases progressively 15 º at skeletal maturation • Adults• Anteversion• Average of 8 º in men and 14º in women• Most common cause of in-toeing

• If associated with internal tibial torsion, may lead to patellofemoral subluxation due to an increase in the Q-angle

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Tumors and Neoplasms

• Young, healthy athletes do get cancer!

• Fortunately most tumors are benign!

• Bone pain at night

• Tumor till proved otherwiseRenström, 2008

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Hip Joint Labral Tear

• Chronic

• Secondary to acetabular dysplasia

• Part of “rim lesion” complexRenström, 2008

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Labrum Tears and Cartilage LossLabrum Tears and Cartilage Loss

• Labrum tears and cartilage loss are common in patients with mechanical symptoms in the hip

• In young, active patients with a complaint of groin pain

• The diagnosis of a labrum tear should be suspected and investigated as radiographs and the history may be nonspecific for this diagnosis

Burnett et al., J Bone Joint Surg (Am), 2006

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MR-Arthrography (MRA)

• MR arthrogram has an accuracy of 91% for labral tears

Chan et al, Arthroscopy 2005

• Sensitivity labral tear • MR 25%,

• MRA 92%Toomayan et al., Am J Roentgenol 2006

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Pincer Impingement

• The acetabulum covers too much of the femoral head

• Secondary to “retroversion”, of the socket

• Or a “profunda” socket that is too deep • Most of the time the cam and pincer

forms exist together• Female, 30-40 yearsRenström, 2008

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• Loss of roundness contributes to abnormal contact between the head and socket

• Male, 20-30 yearsRenström, 2008

Cam Impingement MOB TCD

P Renstrom 08

Cam Impingement MOB TCD

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