Artificial joint replacement

Question 1

Indications for joint surgery and types of joint surgery

Answer 1

• Indications: pain unrelieved by medication/other measures, interrupts sleep, hinders ability to perform daily activities, reduces quality of life
• 4 categories of surgical Rx for osteoarthritis (OA): osteotomy, debridement, arthrodesis, arthroplasty

Question 2

Osteotomy

Answer 2

• Joint malalignment distributes forces abnormally (destruction progresses)
• Cut the bone and realign, corrects malalignment
• There is joint sparing
• For young active pts

Question 3

Debridement and arthrodesis

Answer 3

• Debridement: rarer now, removes inflamed synovium
• Better if there are specific lesion that can be fixed (meniscal tears)
• Arthrodesis: joint fusion, eliminates motion at the joint
• No motion = no pain
• Requires mobility of adjacent joints and increases stress on adjacent joints

Question 4

Joint arthroplasty

Answer 4

• Changing joint surface
• Total joint arthroplasty (TJA): replacement of a joint
• Best for pain relief, function and motion
• There is potential for wear, loosening, infection
• Must avoid avoid impact activities

Question 5

Contraindications to TJA (!)

Answer 5

• Active infections in the joint needing replacement
• Most important is active infection (absolute contraindication)
• Relative contraindications: obese, neuropathic joints, progressive neurological disease, young age (<45)

Question 6

Total hip arthroplasty (THA)

Answer 6

• Increasing incidence
• Total knee arthroplasty recover slower than hips
• They last much longer than 10 years, most don’t require revision
• Complications: infection, DVT without prophylaxis, fatal PE, leg length difference

Question 7

Hip surface replacement

Answer 7

• Large heads have less risk of dislocation
• Metal/metal articulation
• Risks: femoral neck fracture (older women)
• Best candidate is young male (<50)
• Uses the same incision/esposure as THA

Question 8

Total knee arthroplasty (TKA)

Answer 8

• Increasing incidence
• Indications same as THA
• More difficult rehab than TKA (!)
• Functioning extensor mechanism required for good function (quads + patellar tendon)

Question 9

Long term results of TKA

Answer 9

• Last much more than 10 years (most last lifetime)

- Complications: infection, DVT (w/o prophylaxis)