Hip Joint Anatomy PDF

Functional & Applied Anatomy of the Hip Joint  Hip Joint – General Points ❖ Supports the body weight in standing ❖ Involved in locomotion ❖ ‘Ball & socket’ synovial joint; combines a wide range of movements with great stability; degree of movement sacrificed ❖ Head of...

Functional & Applied Anatomy of the Hip Joint  Hip Joint – General Points ❖ Supports the body weight in standing ❖ Involved in locomotion ❖ ‘Ball & socket’ synovial joint; combines a wide range of movements with great stability; degree of movement sacrificed ❖ Head of femur deeply inserted into acetabulum ❖ Strong & stable construction; considerable force is required to cause injury in normal situations ❖ Major trauma may cause injury (i.e. dislocation. fractures & injuries to joint surfaces & associated structures  Innominate (hip) Bone (Muscle attachments) (Muscle attachments)  The Proximal Femur Fovea capitis Femoral head Greater trochanter Femoral neck (common # site) Intertrochanteric crest (# site) Lesser trochanter Femoral shaft Posterior aspect Acetabulum ;Synovial membrane * Attached to margins of articular surfaces site of pathology in (Fibrocartilage) of the femur & acetabulum Inflammatory hip & surrounds the ligament of disease the (Articular) & head of femur lines the fibrous capsule internally  Hip Joint – Anterior view (fibrous capsule cut open) Artery of the ligament of head of femur Obturator artery passing through the ) obturator canal; an opening in the (obturator foramen Acetabular branch  Articular Capsule & Ligaments ❖ Strong & dense articular capsule ❖ Attached proximally to the edge of the acetabulum, glenoid labrum & transverse acetabular ligament ❖ Attached distally to along the intertrochanteric line anteriorly & posteriorly above the intertrochanteric crest ❖ The capsule is thickened by three strong ligaments – iliofemoral (IlF), pubofemoral(PF) & ischiofemoral (IsF) – which spiral around the capsule so as to limit excessive movement of the joint ❖ Transverse acetabular & ligament of the head of femur are accessory ligaments  Capsular Ligaments Anterior view Posterior view IlF PF IsF IlF (Iliofemoral ligament) – strongest; PF (Pubofemoral) & IsF (Ischiofemoral) help relaxed in flexion & taut in extension to reinforce the inferior & posterior aspect prevents hyperextension of the hip PF prevents hyperabduction of the hip in upright position, stabilises the hip by IsF pulls the femoral head into the pulling the femoral head firmly into acetabulum acetabulum & prevents hyperextension  Psoas Iliopsoas Major Movements by Muscles Iliacus Gluteus Tensor Adductor maximus fasciae longus latae Adductor Sartorius magnus Rectus Gracilis femoris Biceps * *Semimembranosus femoris Semitendinosus * Hamstring * muscles Flexors Adductors Extensors  Lateral rotators Abductors Gluteus minimus Short posteriorly placed muscles Gluteus medius Piriformis Superior gamellus Obturator internus Inferior gamellus Quadratus femoris  Nerve Supply to the Hip Joint Superior gluteal nerve * Femoral Nerve (L 2,3,4) Obturator Nerve * (L 2,3,4) * * Sciatic nerve Blood Supply to the Hip Joint * * * * * (Profunda femoris) * Blood Supply to the Hip Joint ❖ Lateral & medial circumflex arteries travel in the capsular retinacula (reflections of the capsule) towards the head; retinacular arteries may be severed in fractures of the neck of the femur ❖ Femoral head also receives supply from the obturator artery – via the ligament of the head of femur; important source of supply before the fusion of epiphysis of head of femur  Common Disorders of the Hip Joint ❖ Dislocations – Congenital & Acquired ❖ Femoral neck fractures (Intracapsular) ❖ Trochanteric fractures (Extracapsular) ❖ Bursitis ❖ Arthritis – Osteoarthritis & Rheumatoid arthritis ❖ Osteonecrosis Hip Dislocations Congenital Hip Dislocation (CDH) ❖ Occurs in 1.5 births in 1000 ❖ Bilateral in half the cases; 1:8 girls : boys ❖ Associated with shallow acetabulum; femoral head not properly located in the acetabulum ❖ Inability to abduct the thigh ❖ Affected limb is shorter because the dislocated femoral head is placed more superiorly ❖ Slipped upper femoral head tends to occur in boys of 10-15 years; presents as “coxa vara” deformity – angle of femoral neck on the shaft is reduced Acquired (traumatic) Hip Dislocations ❖ Uncommon because of strong and stable articulation ❖ Posterior dislocation - cccurs when trauma on a flexed hip during driving accident; head-on collision causes the knee to strike the dashboard; drives the femur posteriorly ❖ Femoral head is forced out of the acetabulum tearing the capsule inferiorly & posteriorly  Posterior Hip Dislocation - Consequences Affected limbshortened & May stretching or compress the medially (internally) rotated sciatic nerve > paralysis of hamstring muscles & muscles distal to the knee & sensory deficits in the leg (posterolateral) over the foot * Sciatic nerve lies posteriorly to the hip joint * Femoral Fractures (Proximal)  Femoral Neck Fractures Disruption of blood supply to the head of femur via circumflex arteries (particularly medial circumflex artery – main supply) ? avascular necrosis> hip replacement Hip Replacements – Contextual Perspectives !!!  Femoral Trochanteric (Extracapsular) Fractures Head Neck GT Intracapsular Normal LT Hip Extracapsular Bursae in the Hip Region Several bursae that are of clinical importance Hip Joint Bursa & Bursitis Iliotibial tract & Gluteus❖ Largest – maximus m. Trochanteric bursa – situated between the gluteus maximus muscle & posterolateral surface of the greater trochanter ❖ Inflammation of this Trochanteric bursa bursa * (trochanteric bursitis) can occur in various types of arthritis or as a separate entity; occurs in patients with lumbar spine pathology & gait disturbances * Hip Joint Bursa & Bursitis ❖ Iliopectineal bursa – lies between the deep surface of the iliopsoas muscle and the anterior surface of the articular capsule of the joint; communicates with the cavity of the hip joint(15% of individuals); swelling of the bursa may present as a synovial cyst of the hip below the inguinal ligament ❖ Ischiogluteal bursa – Site of iinsertion of situated near the ischial.Iliopsoas m tuberosity & over lies the sciatic nerve; can become inflamed due to excessive friction in riding a bicycle or riding a horse Hip Joint Disease  Arthritis ❖ “Arthritis” (inflammation of a joint) is generally used to describe the condition which there is damage to cartilage ( “osteochondrosis” or “osteoarthrosis” ) ❖ Inflammation, if present is in the synovium; proportion of cartilage damage & synovial inflammation varies with the type & stage of arthritis ❖ Usually the pain early on is due to inflammation; in the later stages when the cartilage is destroyed, most pain comes from the mechanical friction of raw bones rubbing on each other  Osteoarthritis Bony (arthritic) spurs (osteophytes) develop on the margins of the joint; Normal Hip Joint ostephytes restrict joint Arthritic Hip Joint movement ❖ “Osteoarthritis mainly damages the joint cartilage; there is some inflammation; some conditions (e.g. joint fracture) may predispose the hip to osteoarthritis; joint space is narrowed & irregular in outline ❖ Osteoarthritic hip – cartilage cushion is thinner than normal, leaving “bare spots” on the bone; grinding bone surfaces cause mechanical pain; fragments of cartilage floating in the joint may cause inflammation Rheumatoid arthritis ❖ Rheumatoid arthritis starts in the synovium & is mainly “inflammatory”; it eventually destroys the joint cartilage and the bone next to cartilage is also damaged and becomes soft; x-rays changes are similar to osteoarthritis  Osteonecrosis ❖ Another cause of hip pain > femoral head dies; dead bone cannot withstand the stresses of walking > the femoral head collapses > becomes irregular in shape ❖ The cause of this disorder is unknown (“idiopathic”) * Common in children of 3 to 9 years; blood supply to the head of the femur is disrupted > “post-traumatic avascular necrosis of the head of femur ” * Femoral head becomes compressed & slippage of the head along the epiphyseal plate may occur