Abstract
BACKGROUND: Total knee arthroplasty surgery (TKA) using prenavigated Patient Specific Instruments (PSI) technique represents one of the most recent technological evolutions in development of prosthetic surgery. The aim of this study was to evaluate kinematic and functional recovery of patients operated with prenavigated PSI technique compared to those operated with traditional technique. METHODS: A cohort of 20 patients is divided in two groups; some are operated with traditional technique (with NexGen Knee system) and others with prenavigated PSI technique (with eMP Knee system) at Asiago Hospital. Limb circumferences are measured for edema evaluation and different evaluation forms are provided to patients: SF-36, KSS pre-surgery (T0), KSS 15 (T1) and 45 days after surgery (T2). Gait Analysis is performed 60 days post-surgery, after leaving crutches. RESULTS: The analysis of KSS and SF-36 evaluation forms shows a greater improvement in PSI Evolution group in terms of articulation (comparison between T0 and T1), knee function and early return to physical and social activities. Pain is lesser in NexGen group, in an earlier phase, but 45 days after surgery (T2) there are no significant differences between two groups. Perception of general state of health improves more and earlier in NexGen. In NexGen group edema evaluation had significant differences at the level of prosthetic leg, but not in knee and thigh. Overall: the walking pattern is more physiological in PSI Evolution group. CONCLUSIONS: The present study highlighted the superiority of prenavigated PSI technique over traditional technique in recovering functionality of prosthetic knee and in restoring a more physiological path pattern.