Lecture 6 Clinical correlates of hip Flashcards
How would you test to see if your patient had a superior gluteal nerve injury?
-the superior gluteal nerve supplies the abductors of the hip (gluteus medius/minimus)
-ask them to stand on their injured lower limb
-if pelvis on unsupported side descends= positive Trendelenburg sign
(usually the gluteus minimus/medius contract, preventing tilting of pelvis on unsupported side)
How do pulled hamstrings occur?
- Sudden muscular exertion resulting in stretching of posterior thigh muscles (jumping, sprinting, lunging)
- common in footballers/athletes, especially if not warmed up
- tension on hamstrings results in muscle sprain, partial/complete tear of origin of hamstring muscles from ischial tuberosity, avulsion fracture
What is an avulsion fracture?
Injury to bone where tendon/ligament attaches to bone
tendon/ligament pulls off a piece of bone
What is osteoarthritis?
Most common disease affecting synovial joints
- degenerative disorder arising from the breakdown of hyaline cartilage
- chronic disease, non-inflammatory
What age range does osteoarthritis affect & what are the symptoms?
Elderly
- joint pain
- functional limitation
- reduced quality of life
What are the common joints affected by osteoarthritis?
- hips
- knees
- cervial/lumbar spine
- small joints of the hand
What are the different classes of osteoarthritis?
Primary: cause is unknown
Secondary: known precipitating cause
What are the risk factors of primary osteoarthritis?
- age
- female sex
- ethnicity (increased risk in african-americans, american indian, hispanic)
- genetics
- nutrition (consumption of vit C&E may help)
What are some secondary causes of osteoarthritis?
- obesity
- trauma (including sports)
- malalignment (developmental dysplasia of hip- congenital hip displacement)
- infection (TB, septic arthritis)
- inflammatory arthritis (rheumatoid, ankylosing spondylitis)
- metabolic disorders affecting joints (gout)
- haematological disorders (bleeding into joints)
- endocrine abnormalities (diabetes with neurovascular impairment-chronic malalignment of articular surfaces)
Symptoms of osteoarthritis?
- deep aching joint pain, worsened by use
- reduced range of motion
- crepitus (grinding)
- stiffness during rest
What leads to hyaline damage?
Uneven loading of the joint due to risk factors
What happens to the hyaline cartilage?
- becomes swollen due to increased proteoglycan synthesis by chondrocytes, with increased number of chondrocytes differentiating from chondroprogenitor cells (reflects attempt to repair cartilage)
- proteoglycan content gradually falls as disease progresses
- cartilage softens and loses elasticity
- flaking and fibrillation seen
- cartilage becomes eroded down to the bone resulting in loss of joint space
What does the surface changes in osteoarthritis trigger?
Alter the distribution of biomechanical forces
- subchondral bone responds with vascular invasion and increased cellularity: becoming thicker and denser
- subchondral bone may undergo cystic degeneration to form subchondral bone cysts (fluid filled spots in bone) which make the bones weak, attributes to osseous necrosis/intrusion of synovial fluid
What is eburnation?
Subchondral bone responds with vascular invasion and increased cellularity: becoming thicker and denser
(subchondral sclerosis: hardening of bone just below cartilage surface)
What occurs at articular margin of the bones?
Osseous metaplasia of connective tissue
-irregular outgrowth of new bone (osteophytes)