Kinematic Comparison of Vanguard XP and Vanguard CR Total Knee Arthroplasties

Comparison of Vanguard XP and Vanguard CR Total Knee Arthroplasties: A Cross Sectional Pilot Study Evaluating Intraarticular Kinematics and Standing Balance by Dynamic Fluoroscopy and Force Plate Examination

Primary: The primary objective of this pilot study is to compare the intraarticular kinematics by fluoroscopy of Vanguard XP to that of Vanguard CR.

Secondary: The secondary objective of this pilot study is to compare the standing balance by force plate of patients with the Vanguard XP prosthesis to those who have Vanguard CR prosthesis. Furthermore, we wish to assess isometric quadriceps muscle strength in both groups.

Inclusion Criteria:

• Participant in the XP vs. CR study (inherited traits from study inclusion)
• Overall healthy. Have attended standard physiotherapy after unilateral total knee replacement
• Are able to perform the tasks
• Excellent clinical scores (Oxford Knee Score above 39 at 1 year follow up)

Exclusion Criteria:

• Knee pain above 20 on a 0-100 visual analogue scale
• Any clinical relevant pain from adjacent joints
• Active Knee flexion below 100
• Signs of implant migration, loosening, and implant mal-alignment