[Comparison of effectiveness of total knee arthroplasty with tantalum monoblock tibial component and cemented tibial plateau prosthesis in patients of different ages].

Objective: To investigate the difference of total knee arthroplasty (TKA) with tantalum monoblock tibial component (TMT) and cemented tibial plateau prosthesis in patients of different ages.
Methods: The clinical data of 248 patients (392 knees) who underwent primary TKA between May 2014 and May 2019 and met the selection criteria were retrospectively analyzed. There were 54 males (98 knees) and 194 females (294 knees). Of the 122 patients (183 knees), less than 65 years old, 52 (75 knees, group A1) were treated with TMT and 70 (108 knees, group B1) were treated with cemented tibial plateau prosthesis; of the 126 patients (209 knees), more than 65 years old, 57 (82 knees, group A2) were treated with TMT and 69 (127 knees, group B2) were treated with cemented tibial plateau prosthesis. The baseline data of patients, perioperative indicators [hemoglobin (Hb), hematocrit (Hct), total blood loss, unilateral operation time], effectiveness evaluation indicators [Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, visual analogue scale (VAS) score, Knee Society Scoring System (KSS) score, active flexion and extension range of motion (ROM) of the knee joint], complications, and imaging indicators [tibial prosthesis varus angle (β angle), tibial prosthesis posterior slope angle (δ angle), tibio-femoral angle, occurrence of radiolucent line, prosthesis survival rate] were recorded and compared.
Results: There was no significant difference in gender, age, height, weight, body mass index, Kellgren-Lawrence grading, the length of hospital stay, and follow-up time between groups A1, B1 and groups A2, B2 ( P >0.05). The unilateral operation time in groups A1 and A2 was significantly shorter than that in the corresponding groups B1 and B2 ( P <0.05). There was no significant difference in differences of pre- and post-operative Hb and Hct and total blood loss between groups A1, B1 and groups A2, B2 ( P >0.05). There was no significant difference in preoperative effectiveness evaluation indicators between groups A1, B1 and groups A2, B2 ( P >0.05). There were significant differences in the differences of pre- and post-operative WOMAC activity and pain scores, KSS function and pain scores, and VAS scores between groups A1 and B1 ( P <0.05); there was no significant difference in WOMAC stiffness score and ROM ( P >0.05). There was no significant difference in the above indicators between groups A2 and B2 ( P >0.05). There was no significant difference in the incidence of complications (2.7% vs 6.5%, 3.7% vs 3.1%) and prosthesis survival rate (100% vs 97.2%, 100% vs 99.2%) between groups A1, B1 and groups A2, B2 ( P >0.05). During follow-up, there was no significant difference in β angle, δ angle, and tibio-femoral angle between groups A1, B1 and groups A2, B2 ( P >0.05). In the evaluation of knee X-ray radiolucent line, 2 knees of group A1 and 2 knees of group A2 had radiolucent line at prosthesis-bone interface immediately after operation, and the radiolucent line was gradually filled by new bone, without new radiolucent line. During follow-up, 1 knee of group B1 and 1 knee of group B2 had prosthesis-bone interface radiolucent line, without radiolucent line widening or prosthesis loosening.
Conclusion: TMT is recommended in patients less than 65 years old, and the two types of prostheses are available for patients nore than 65 years old. However, the long-term effectiveness of the two types of prosthesis in patients of different ages needs further follow-up.