|
https://upload.orthobullets.com/topic/5005/images/osteoarthritis.jpg
https://upload.orthobullets.com/topic/5005/images/chart.jpg.jpg
https://upload.orthobullets.com/topic/5005/images/bioche_mical.jpg
https://upload.orthobullets.com/topic/5005/images/false_profile_(orthopaedia.net)..jpg
https://upload.orthobullets.com/topic/5005/images/crossover_sign_(orthopaedia.net)..jpg
Introduction
  • Definition
    • degenerative disease of synovial joints that causes progressive loss of articular cartilage
  • Epidemiology
    • incidence
      • hip OA (symptomatic)
        • 88 per 100,000 per year
      • knee OA (symptomatic)
        • 240 per 100,000 per year
  • Risk factors 
    • modifiable
      • articular trauma
      • muscle weakness
      • heavy physical stress at work
      • high impact sporting activities 
    • non-modifiable
      • gender
        • females >males
      • increased age
      • genetics
      • developmental or acquired deformities
        • hip dysplasia
        • slipped capital femoral epiphysis
        • Legg-Calvé-Perthes disease
  • Pathophysiology
    • pathoanatomy 
      • articular cartilage 
        • increased water content 
        • alterations in proteoglycans 
          • eventual decrease in amount of proteoglycans
        • collagen abnormalities 
          • organization and orientation are lost
          • binding of proteoglycans to hyaluronic acid
      • synovium and capsule
        • early phase of OA
          • mild inflammatory changes in synovium
        • middle phase of OA
          • moderate inflammatory changes of synovium
          • synovium becomes hypervascular
        • late phases of OA
          • synovium becomes increasingly thick and vascular
          • bone
          • subchondral bone attempts to remodel 
          • forming lytic lesion with sclerotic edges (different than bone cysts in RA)
          • bone cysts form in late stages
  • Cell biology
    • proteolytic enzymes 
      • matrix metalloproteases (MMPs)
        • responsible for cartilage matrix digestion
        • examples
          • stromelysin 
          • plasmin
          • aggrecanase-1 (ADAMTS-4)
      • tissue inhibitors of MMPS (TIMPs)
        • control MMP activity preventing excessive degradation
        • imbalance between MMPs and TIMPs has been demonstrated in OA tissues
      • inflammatory cytokines
        • secreted by synoviocytes and increase MMP synthesis
          • examples
            • IL-1
            • IL-6
            • TNF-alpha
  • Genetics
    • inheritance
      • non-mendilian
    • genes potentially linked to OA
      • vitamin D receptor
      • estrogen receptor 1
      • inflammatory cytokines
        • IL-1
          • leads to catabolic effect
        • IL-4
        • matrilin-3
        • BMP-2, BMP-5
Presentation
  • History
    • identify age, functional activity, pattern of arthritic involvement, overall health and duration of symptoms
  • Symptoms
    • function-limiting hip pain 
      • effect on walking distances
    • pain at night or rest
    • hip stiffness
    • mechanical 
      • instability, locking, catching sensation
  • Physical exam
    • inspection
      • body habitus
      • gait
      • leg length discrepancy 
      • skin (e.g. scars)
    • range of motion
      • lack of full extension (>5 degrees flexion contracture)
      • lack of full flexion (flexion < 90-100 degrees) 
      • limited internal rotation
  • Neurovascular exam
    • straight leg test negative
Imaging
  • Radiographs
    • recommended views
      • standing AP pelvis
      • AP + lateral hip
    • optional views
      • false profile view (e.g. hip dysplasia)  
    • findings
      • osteoarthritis
        • joint space narrowing 
        • osteophytes 
        • subchondral sclerosis 
        • subchondral cysts 
      • pelvic obliquity
        • may be secondary to spinal deformity
        • may cause leg-length issues
      • acetabular retroversion  
        • makes appropriate positioning of acetabular component more difficult intraoperatively
Studies
  • Histology
    • loss of superficial chondrocytes
    • replication and breakdown of the tidemark
    • fissuring
    • cartilage destruction with eburnation of subchondral bone
Treatment
  • Nonoperative 
    • NSAIDs and/or tramadol
      • indications
        • first line treatment for all patients with symptomatic arthritis
      • technique
        • NSAID selection should be based on physician preference, patient acceptability and cost
    • walking stick
      • decreases the joint reaction force on the affected hip when used in the contralateral upper extremity
    • weight loss, activity modification and exercise program/physical therapy
      • indications
        • first line treatment for all patients with symptomatic arthritis
        • BMI > 25
      • technique
        • exercise aimed at increasing flexibility and aerobic capacity
    • corticosteroid joint injections
      • indications
        • can be therapeutic and/or diagnostic of symptomatic hip osteoarthritis
    • controversial treatments
      • acupuncture
      • viscoelastic joint injections
      • glucosamine and chondroitin
  • Operative
    • arthroscopic debridement 
      • indications
        • controversial 
        • degenerative labral tears
    • periacetabular osteotomy +/-  femoral osteotomy
      • indications
        • symptomatic dysplasia in an adolescent or young adult with concentrically reduced hip and mild-to-moderate arthritis
      • outcomes
        • mixed results
        • literature suggest this can delay need for arthroplasty
    • femoral head resection
      • indications
        • pathological hip lesions 
        • painful head subluxation
    • hip resurfacing
      • indications
        • young active, male, patients with hip osteoarthritis
    • total hip arthroplasty (THA)
      • indications
        • end-stage, symptomatic or severe osteoarthritis arthritis
        • preferred treatment for older patients (>50) and those with advanced structural changes
 
 

Please rate topic.

Average 4.2 of 52 Ratings

Technique Guides (2)
Questions (2)

(OBQ04.70) Which of the following characteristics of stromelysin is incorrect? Review Topic

QID: 1175
1

Belongs to the family of proteolytic enzymes called metalloproteinases

14%

(113/805)

2

Secreted by chondrocytes

17%

(139/805)

3

Inhibited by Tissue Inhibitor of Metalloproteinase

9%

(69/805)

4

Inhibited by plasmin

46%

(370/805)

5

Degrades cartilage and is thought to play a role in degenerative joint disease

13%

(108/805)

Select Answer to see Preferred Response

PREFERRED RESPONSE 4

(OBQ05.39) Which of the following is a characteristic change in cartilage involved in moderate osteoarthritis? Review Topic

QID: 76
1

Decreased thickness of subchondral bone

3%

(62/2064)

2

Decreased chondrocyte activity

21%

(441/2064)

3

Increased proteoglycan quantity

7%

(144/2064)

4

Increased water content

65%

(1335/2064)

5

Increased collagen quantity

4%

(79/2064)

Select Answer to see Preferred Response

PREFERRED RESPONSE 4
EVIDENCE & REFERENCES (14)
VIDEOS (2)
CASES (4)
GROUPS (1)
Topic COMMENTS (20)
Private Note