Knee Replacement
Name any three structures that could be impacted by a knee replacement surgery
Any of:
- ligaments
- vessels
- nerves
Name the 4 main ligaments of the knee
anterior cruciate ligament
posterior cruciate ligament
lateral collateral ligament
medial collateral ligament
Name three differences between the medial and lateral menisci.
• Shape: Medial = C-shaped, Lateral = O-shaped
• Attachment: Medial firmly attached to joint capsule & MCL → less mobile; Lateral loosely attached → more mobile
• Injury Risk: Medial tears more common due to reduced mobility
Name three risk factors for osteoarthritis
- age
- gender
- obesity
- genetics
- joint injury/overuse
- anatomical factors (malalignment/congenital abnormalities)
Name the most common approach to knee replacements:
a) Medial parapatellar approach
b) Lateral parapatellar approach
c) Midvastus approach
What is the medial parapatellar approach?
What arteries supply the collateral ligaments? Can you name all of them?
Genicular arteries
(bonus: superior medial genicular artery, superior lateral genicular artery, middle genicular artery, inferior medial genicular artery, and inferior lateral genicular artery)
Describe two classic symptoms that a patient with a meniscal tear might report during history-taking.
• Locking, catching, or clicking sensation in the knee
• Joint-line pain, swelling (effusion) that develops hours after injury
(bonus: feelings of instability, difficulty fully straightening the knee)
what clinical and radiographic features help differentiate osteoarthiritis from rheumatoid arthritis in the knee?
OA --> osteophytes, subchondral sclerosis, asymmetry, pain with use
RA --> erosions, osteopenia, symmeetry, prolonged inflammatory stiffness
A disadvantage of the medial parapatellar approach
- may jeopardise patellar circulation
- possible failure of medial capsular repair
- development of lateral patellar subluxation
- access to lateral retinaculum less direct
What tests would be positive in the unhappy triad?
a) Valgus stress test
b) McMurray Test
c) Anterior Draw Test
d) Lachman Test
This classic clinical sign of a meniscal tear is characterised by joint-line tenderness, pain on deep flexion, and a palpable “click” or “pop” during this special test.
McMurray’s test
what is typically the first treatment?
NSAIDs