[Effectiveness of cementless total knee arthroplasty with three-dimensional-printed trabecular metal interface]

To investigate the short- and mid-term effectiveness and prosthesis survival rate in patients undergoing total knee arthroplasty (TKA) using domestic cementless knee prostheses with three-dimensional (3D)-printed trabecular metal interface.

A retrospective analysis was performed on the clinical data of 79 patients who underwent primary TKA for end-stage knee disorders, met the selection criteria and were treated between December 2021 and March 2022. There were 39 patients in the cementless group receiving cementless knee prostheses with 3D-printed trabecular metal interface, and 40 patients in the cemented group adopting posterior-stabilized cement-fixed knee prostheses. Baseline data including age, gender, body weight, disease type, disease duration, and preoperative Knee Society Score (KSS) (clinical score and function score) showed no significant differences between the two groups ( P>0.05). Operation time, intraoperative blood loss, and complications were recorded and compared between groups. KSS clinical and function scores before operation and at last follow-up were used to evaluate knee functional recovery. Radiographic assessment was conducted to detect prosthesis loosening, osteolysis, prosthesis subsidence, joint dislocation, and other abnormalities. Prosthesis survival rate was calculated with complete or partial prosthesis removal defined as the endpoint event, and Kaplan-Meier method was adopted to plot prosthesis survival curves.

All patients successfully completed surgery. No significant intergroup differences were found in operation time and intraoperative blood loss ( P>0.05). All patients in the cementless group and cemented group were followed up for (28.4±2.4) months and (28.2±2.8) months respectively, without significant difference ( t=-0.274, P=0.785). At last follow-up, both KSS clinical and function scores were significantly higher than preoperative values in both groups ( P<0.05), while no significant intergroup differences were observed in the changes of each score ( P>0.05). X-ray films at last follow-up revealed no prosthesis loosening, osteolysis, prosthesis subsidence, or joint dislocation in any patient. During follow-up, 5 cases of intermuscular venous thrombosis occurred in the cementless group; in the cemented group, there were 6 cases of intermuscular venous thrombosis, 1 case of poor wound healing, 1 case of periprosthetic joint infection, 1 case of periprosthetic fracture, and 1 case of all-cause death. The complication rates of the two groups (12.8% vs 25.0%) were not different ( P>0.05). One revision surgery was performed for periprosthetic joint infection and 1 for periprosthetic fracture in the cemented group, corresponding to a prosthesis survival rate of 95.0%; no endpoint events occurred in the cementless group, with a prosthesis survival rate of 100.0%. Kaplan-Meier survival curve analysis demonstrated no significant difference in prosthesis survival rates between the two groups (Log-rank test: χ ²=2.028, P=0.154).

TKA performed with domestic cementless knee prostheses featuring 3D-printed trabecular metal interface shows no obvious disadvantages compared with cemented prostheses in terms of postoperative function, complication rate, and prosthesis survival rate, which represents a safe and viable prosthesis option.