[Short-term effectiveness of total knee arthroplasty assisted by three-dimensional printing osteotomy navigation template].

Objective: To investigate the short-term effectiveness of total knee arthroplasty (TKA) assisted by three-dimensional (3D) printing osteotomy navigation template.

Methods: A retrospective study was performed on 60 patients with osteoarthritis bewteen January 2016 and June 2017. Thirty cases underwent TKA assisted by 3D printing osteotomy navigation template (3D printing group) and 30 cases underwent the conventional TKA (conventional TKA group). There was no significant difference in gender, age, body mass index, surgical side, and disease duration between 2 groups ( P >0.05). The operation time, the pre- and post-operative hemoglobin values, the amount of drainage, the Hospital for Special Surgery (HSS) score and Knee Society Score (KSS) of knee joint before operation and at 3 months after operation were observed. And 6 freedom degrees of knee (the varus and valgus angle, the internal and external rotation angle, the antero-posterior displacement, the proximal-distal displacement, the flexion and extension angle, and the internal and external displacement) before operation and at 3 months after operation were recorded by Opti-Knee (the knee 3D motion analysis system). The values of 2 groups were compared with 30 healthy adults (<60 years).

Results: The operation time was shorter in 3D printing group than that in conventional TKA group ( t =5.833， P =0.000). The hemoglobin values at 1 and 3 days after operation were higher in 3D printing group than those in conventional TKA group ( P <0.05). The amount of drainage was less in 3D printing group than that in conventional TKA group ( t =5.468， P =0.000). All patients were followed up 6-9 months (mean, 7.3 months). There was no significant difference in pre- and post-operative HSS score and KSS clinical score between 2 groups ( P >0.05). There was no significant difference in preoperative KSS function score between 2 groups ( P >0.05), but the KSS function score of 3D printing group at 3 months after operation was higher than that of conventional TKA group ( P <0.05). Before operation, the varus and valgus angle, the internal and external rotation angle, the antero-posterior displacement, the proximal-distal displacement of 3D printing group and conventional TKA group were larger than that of the healthy adults ( P <0.05); there was no significant difference in the flexion and extension angle and the internal and external displacement between 2 groups and healthy adults ( P >0.05). At 3 months after operation, compared with healthy adults, the varus and valgus angle of conventional TKA group was increased, the flexion and extension angle of conventional TKA group was decreased ( P <0.05); the proximal-distal displacement and the internal and external displacement of 2 groups were decreased ( P <0.05); there was no significant difference in other freedom degrees between groups ( P >0.05). No sign of prosthesis loosening was observed by X-ray examination.

Conclusion: Compared with the traditional TKA, TKA assisted by the 3D printing osteotomy navigation template had such advantages as shorter operation time, less postoperative blood loss, and well postoperative recovery.