Knee extensor function before and 1 year after simultaneous bilateral total knee arthroplasty: is there asymmetry...

Area of Science:

• Orthopedic surgery
• Biomechanics
• Rehabilitation science

Background:

• Unilateral total knee arthroplasty (TKA) often leads to knee extensor function asymmetry between limbs one year post-operation.
• The functional implications of simultaneous bilateral TKA on interlimb symmetry remain less understood.

Purpose of the Study:

• To investigate knee extensor function symmetry between limbs one year after simultaneous bilateral TKA.
• To compare the functional outcomes of bilateral TKA with known outcomes of unilateral TKA regarding limb symmetry.

Main Methods:

• Eight patients who underwent simultaneous bilateral TKA for knee osteoarthritis participated in follow-up testing.
• Isokinetic assessment of knee extensor torque production, work, and range of motion at 1.047 rad/s was performed one year after surgery.
• Pre-operative data confirmed no significant interlimb differences in these parameters.

Main Results:

• No significant differences in peak torque, work, or range of motion were observed between limbs one year after simultaneous bilateral TKA.
• The symmetrical pattern of knee extensor function persisted from pre-operative levels.
• This contrasts with findings from unilateral TKA, where strength asymmetry is typically present.

Conclusions:

• Simultaneous bilateral TKA promotes symmetrical knee extensor function between limbs one year post-operatively.
• This surgical approach may mitigate the interlimb asymmetry commonly seen after unilateral TKA.
• Bilateral TKA appears to maintain functional balance between the lower extremities.