Degenerative and Inflammatory Joint Disease Flashcards
components of articular cartilage
- thin superficial (tangential) zone
- middle (transitional) zone
- deep (radial) zone
- calcified zone
resistance to compressive forces
middle -> deep
proteoglycans (CHONDROITIN, keratan sulfate)
type of collagen in the ecm of cartilage
type 2
hip pain radiates towards __
groin, lateral aspect of thigh, anterior thigh
mostly due to extremes of motion
hallmark sign of weakness of hip abductors
trendelenburg sign
- stance phase of gait cycle
- weakness of abductors = dip on contralateral side
range of motion of hip
flexion: 0-135 deg
extension: 0-30 deg
abduction: 45-50 deg
adduction: 20-30 deg
ext rot: 0-45 deg
int rot: 0-35 deg
range of motion of knee
flexion 0-130 deg
full extension 0 deg
full flexion 100 deg
pathophysio of osteoarthritis
- increase in inflammatory markers (il-6 il-1)
- final common pathway = injury to articular cartilage
- most common form of arthritis
clinical manifestations of osteoarthritis
- women: hands and knees (distal interphalangeal joints)
- men: hips
- altered balance -> falls
- stiffness (>30 min in morning), swelling and pain, crepitus
pathologic findings in osteoarthritis
- fibrillation of cartilage
- increase in water content
- altered proteoglycan content (inc)
- decreased collagen
diagnosis of osteoarthritis
- no gold standard
- xray: joint space narrowing, subchondral sclerosis, osteophytes
pathophysio of rheumatoid arthritis
- autoimmune, chornic
- unknown cause (genetic, bacterial, mycoplasmal, viral)
clinical manifestations of rheumatoid arthritis
polyarthritis
- wrist, metacarpophalangeal, proximal interphalangeal
- elbow
- shoulder
- cervical spine
- hip, knee, ankle
- usually symmetrical/bilateral and migratory
extra-articular involvement
- vasculitis, pericarditis, skin nodules
- pulmonary fibrosis
- penumonitis and scleritis
- felty’s syndrome (arthritis, lymphadenopathy, and splenomegaly)
pathologic findings in rheumatoid arthritis
- synovitis
- pannus formation: thickened synovium with activated t and b lymphocytes
labs in rheumatoisd arthritis
- high titer of rheumatoid factor
- uniform loss of joint space
- articular erosions
- periaarticular osteoporosis/ osteopenia
- deformities and subluxations
joint aspiration of ra vs oa
read
general differences between ra and oa
ra: systemic, symmetris, small joints, young
oa: localized, asymmetric, large joints, older
pathogenesis of osteonecrosis of the hip
- traumatic or idiopathic
- risk factors: alcohol abuse, gout, caisson disease, renal osteodystrophy, sickle cell anemia, steroids, trauma
- direct cell toxicity, coagulopathic states, fat emboli, vascular interruptions, elevated bone marrow pressure
ficat classification of avascular necrosis
- higher stage = more symptomatic
- stage of collapse (stage 3) – crescent sign!
read!!
treatment for osteonecrosis depends on __
- symptoms
- collapse of femoral head
- size of the lesion
- degree of involvement of weight bearing surface
- acetabular involvement
pharmacologic agents for osteonecrosis
- in early stages
- statins
- anticoagulants and prostacyclin analogs
- inhibiting aggregation of platelets promotes blood flow
- bisphosphonates
surgical treatment for osteonecrosis
- in later stages
- head-preserving treatment
- arthroplasty/replacement techniques
type of head preserving treatment that is used in patients with >30% involvement of the head
vascularized fibular graft
- preferred for young patients (<50)
- not indicated for early disease
what is arthroplasty
- final option
- larger lesions, > 3% of femoral head surface
types:
- resurfacing hemiarthroplasty
- hemiarthroplasty (poorer results)
- resurfacing arthroplasty
- total hip arthroplasty (most popular, modern)
conservative methods to treat osteoarthritis
- weight loss
- walking aids
- limit activities
- pain medications (acetaminophen, nsaids)
- exercise: strength, rom, agility
injections for osteoarthritis
- lidocaine test: diagnostic
- corticosteroids: therapeutic
- hyaluronic acid: for viscoelasticity
surgical options for osteoarthritis
- joint preserving* (younger)
- joint salvage procedures: arthrodesis
- total joint replacement (hip and knee)
what is joint debridement and synovectomy
- to relieve pain by synovium
- to prolong life of hyaline joint surface
indications for joint debridement and synovectomy
- chronic synovitis
- synovitis limited to membrane
- recurrent hemarthroses
- imminent destruction of joint by lysosomal enzymes from wbcs in infections
- failure of conservative treatment
contraindications for joint debridement and synovectomy
- reduced joint range of motion
- significant arthritis/cartilage involvement
types of synovectomy
- open synovectomy (infectious)
- arthroscopic synovectomy (degenerative arthritis)
- radiation synovectomy (rheumatoid arthritis)
cartilage transplant techniques
- for athletes with focal cartilage defects
- autologous chrondrocyte transplantation
what is osteotomy
- break the bone incompletely so you have a hinge on one side
- allows swinging of the bone in a direction to correct defects
indications for high tibial osteotomy
- varus knees (for valgus = femoral osteotomy)
- unicompartmental arthritis
- relatively younger (<50)
- pts with good range of motion
- no knee instability
- normal bmi
goal: preserve native knee for as long as possible
most common mode of failure of high tibial osteotomy
contralateral compartment disease
reasons to consider osteotomy of the hip
- there is normal viable cartilage that may be moved to weight-bearing area where there was thinned cartilage
- biomechanical load on the joints that cause pain are reduced
what are femoral osteotomies
- performed in the intertrochanteric region
- “derorotation” procedures
what is joint salvage
- creation of a bony fusion across a joint
- for younger or cannot get replacements
what is the girdlestone procedure
- resection of the femoral head without replacement
- last option after failed replacement
indications for girdlestone procedure
- severe infection
- limited function
- unreconstructable bone defects
- poor medical condition
- failed arthroplasty
what is joint replacement
- last option
- to relieve pain
- uses prosthetic devices
indications for total hip replacement
- debilitating pain
- failure of conservative treatment
- medically fit
- no infection
the force generated within a joint in response to the forces acting on it
joint reaction force
indications for total knee replacement
- pain affecting activities of daily life
- failure of conservative management
- no infection
- medically fit for surgery
goals of total knee replacement
- neutral mechanical alignment
- restore the joint line
- normal q-angle
- well balanced knee
complications of arthroplasties
- infection
- neurovascular injuries
- revision (loosening and wear, osteolysis)
- medical (dvt, pe, stroke)
- dislocations
- peri-prosthetic fractures
