🦵

TKR Implants and Choice

TKR Implants
IMPLANT Choice
Exit Exams MCQ QUIZ

TKR Implants

‣

Key knee biomechanics to replicate:

‣

What is the condylar compromise?

‣

Levels of constraint

‣

All-PE vs metal backed modular design in tibial component?

‣

What materials are used in TKR implants?

‣

Single vs Multi-radius femoral components?

‣

What is a Medial Pivot Knee?

‣

When do you use Stems?

‣

Types of patella components?

‣

Femoral trochlea component design evolution?

‣

When do you use hinged implants? Indications for Hinged TKR?

‣

What do you know of the Knee Arthroplasty Trial?

IMPLANT Choice

There are 3 key components in TKR implant choice: CR vs PS, Patellar resurfacing, and type of bearing.

‣

What TKR implant PS vs CR will you choose?

‣

What bearing surface for TKR?

‣

Will you do patellar resurfacing?

‣

Fixed or mobile bearing for TKR?

‣

Cemented vs uncemented TKR?

‣

What type of UKA will you do?

Exit Exams MCQ QUIZ

According to the principle of the 'condylar compromise' in TKR implant design, what is the direct consequence of increasing implant conformity to reduce contact stress?

A. It decreases constraint, allowing for more normal kinematics.

B. It improves femoral roll back without needing a cam-post mechanism.

C. It increases constraint and thus reduces kinematics.

D. It eliminates the risk of polyethylene wear debris.

‣

Answer

What is the primary purpose of a Medial Pivot Knee design?

A. To reduce shear stresses by allowing the tibial insert to rotate on the tibial platform.

B. To provide maximal constraint for global instability.

C. To replicate screw home mechanism

D. To achieve femoral roll back via a cam and post mechanism.

‣

Answer

Which of the following is listed as a primary advantage of a Cruciate Retaining (CR) TKR implant compared to a Posterior Stabilized (PS) implant?

A. It is a bone-preserving procedure as no box cut is needed.

B. It is easier to achieve soft tissue balance.

C. It provides a more congruent joint surface.

D. It eliminates the risk of cam jump and tibial post wear.

‣

Answer

What is a potential downside of using stems in TKR components, as identified in the source material?

A. They increase tibial lift-off in cases of varus/valgus instability.

B. They are unable to effectively resist shear forces.

C. They cause stress shielding, which can reduce bone density.

D. They increase micromotion at the implant-bone interface.

‣

Answer

Why might an all-polyethylene (All-PE) tibial component be chosen over a metal-backed modular design?

A. It has no back side wear, which eliminates a source of osteolysis.

B. It offers greater modularity with more size and thickness options.

C. It is made of titanium for better osseointegration.

D. It allows for easy liner exchange during revision for infection.

‣

Answer

The Knee Arthroplasty Trial (KAT) compared several factors in TKR. What did its 2-year results show regarding patellar resurfacing, mobile bearings, and metal backing?

A. Patellar resurfacing significantly reduced anterior knee pain.

B. There was no difference in functional outcomes for these three factors.

C. Mobile bearings had significantly better functional outcomes.

D. Metal-backed components had a lower revision rate.

‣

Answer

📖

The wicked are overthrown and are no more, but the house of the righteous will stand. Proverbs 12:7