[Effects of iASSIST navigation system and personal specific instrument assisted total knee arthroplasty in the treatment of osteoarthritis].

Objective

To compare the application of iASSIST assisted total knee arthroplasty (TKA) and three-dimentional(3D) printing personal specific instrument (PSI) assist TKA in the treatment of osteoarthritis (OA).

Methods

Clinical data of 47 patients with OA admitted at Department of Orthopaedic Surgery in Nanjing Medical University Nanjing Hospital between April and September 2016 were retrospectively reviewed, including 20 males and 27 females, aging from 57 to 77 years with mean age of (63.8±8.2) years. They were randomly divided into iASSIST-TKA group (23 patients) and PSI-TKA group (24 patients). The data such as hip knee ankle (HKA) angle, frontal femoral component (FFC) angle, frontal tibial component (FTC) angle, lateral femoral component (LFC) angle, lateral tibial component (LTC) angle, time of operation, post-operative wound drainage, period of hospitalization, visual analog scale (VAS) and Knee Society Score (KSS) at 1 day, 7 days, 14 days, 1 month and 3 months were recorded and compared between the two groups. T test was used to compare measurement data, Fisher exact test and χ(2) test were applied to enumeration data in comparison among groups, and Kruskal-Wallis test was applied to ranked data.

Results

The deviation values of HKA, FFC, LFC, FTC and LTC angles were all below 3°(-2° to 2°), and there were no significant difference between iASSIST-TKA group and PSI-TKA group (Z=-0.610 to 0.000, P=0.542 to 1.000). Compared to PSI-TKA group, the time of operation was long((80.7±8.8) minutes vs.(60.2±7.8) minutes), the amount of post-operative wound drainage was increased((210.7±32.1) ml vs.(185.5±30.2)ml) and the period of hospitalization decreased((5.4±2.4) d vs.(6.7±1.6) d) in iASSIST-TKA group, there were significant difference(t=-2.190 to 8.460, P=0.000 to 0.033). There were no significant difference in intra-operative blood drainage((18.4±5.4) ml vs.(17.3±6.2) ml) between the two groups(t=0.650, P=0.521). PSI-TKA group had a superior VAS score(4.8±0.6 vs. 5.5±0.9, 3.6±0.8 vs. 4.3±0.9), KSS clinical score(49.3±5.5 vs. 44.2±6.4, 54.9±4.0 vs. 50.8±4.2) and KSS function score(44.1±2.9 vs. 41.2±3.5, 49.6±3.8 vs. 46.6±3.2) in 1 day and 7 days post-operation(t=-3.420 to 3.150, P=0.001 to 0.007). There were no significant difference in VAS and KSS score in 14 days, 1 month and 3 months post-operation(t=-1.390 to 0.530, P=0.170 to 1.000) between the two groups.

Conclusions

The iASSIST-TKA and PSI-TKA can help to make TKA procedure more accurately. iASSIST-TKA may take longer time of operation and have slower recovery, PSI-TKA may need more X-ray input and longer period of hospitalization. The long-term research of both techniques may be valuable for the further clinical usage.