Comparison of Postoperative Effects between Medial Pivot Prosthesis and Posterior Stabilized Prosthesis

Abstract

Objective: To compare the postoperative inflammation and pain response between medial pivot (MP) and posterior stabilized (PS) prostheses among total knee arthroplasty (TKA) patients. Methods: A prospective cohort study was conducted from January 2019 to May 2019 at the Affiliated Hospital of Qingdao University. The study included patients diagnosed with stage III or IV Kellgren-Lawrence knee osteoarthritis (KOA) who had failed conservative treatment, had undergone no previous knee surgeries, had varus substantial deformities (11-20 deviation), and had received their first unilateral TKA. A total of 109 patients who underwent PS prosthesis TKA and 98 patients who underwent MP prosthesis TKA were continuously enrolled. Inflammation biomarkers, such as leukocyte (white blood cells), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), together with hemoglobin (Hb), the visual analog pain score (VAS) and range of motion (ROM) were compared between the two groups. The Student t-test was applied to analyze continuous parameters, and the χ 2-test was used for categorical parameters. The linear mixed model was used for the repeated measurement data from the follow-up visits. Multivariate backward logistic and linear regression models were used to determine the factors potentially influencing prostheses and VAS scores. Results: All these enrolled patients were followed up at 2, 4, 7, and 30 days after TKA. There were no significant differences between the PS group and the MP group in body mass index (BMI), gender, laterality, usage of nonsteroidal antiinflammatory drugs (NSAIDs) and opioids, and drain tube extubation time (P > 0.05). Compared with the PS group, the MP group were older (67.5 years vs 65.4 years), and had a higher mid-vastus approach rate (67.3% vs 26.6%), a shorter tourniquet duration (68.3 AE 10.2 h vs 73.9 AE 11.2 h), a larger prosthetic pad (10.8 AE 1.2 mm vs 10.4 AE 1.2 mm), and a lower drain tube diversion volume (187.6 AE 119.3 mL vs 234.0 AE 155.7 mL). In the linear mixed model, MP prostheses had less CRP and ESR elevation and less Hb decrease than PS prostheses (P for group × time < 0.001). There were no significant differences in the changing trends between MP and PS prostheses by time for VAS scores and ROM. In the multivariate logistic regression model, MP prostheses showed significant differences compared with PS prostheses in treatment approach (odds ratio [OR] = 3.371, 95% confidence interval [CI]: 1.953-7.127; P < 0.001), ultrasound treatment start time (OR = 2.669, 95% CI: 1.385-5.141; P = 0.003), and tourniquet duration (OR = 0.954, 95% CI: 0.925-0.984; P = 0.003). Higher VAS scores on the second day postoperatively were related to high VAS scores preoperatively, use of opioids, high drain tube diversion, long tourniquet duration, and long drain tube extubation (P < 0.05), respectively. Conclusion: The MP prostheses showed potential advantages compared with PS prostheses in TKA in inflammatory responses.

Medial pivot prosthesis has a better functional score and lower complication rate than posterior-stabilized prosthesis: a systematic review and meta-analysis

“…A total of 13 studies reported ROM [ 4 , 5 , 8 , 11 , 18 , 19 , 21 – 25 , 30 , 32 ]. Since high heterogeneity was indicated ( I 2 = 77%, P < 0.1), sensitivity analyses were conducted.…”

“…After the two researchers read the title and abstract, they further ruled out 563 irrelevant studies. Finally, the researchers reviewed the full text of the remaining 45 studies and determined that 19 studies could be included in the final meta-analysis [4,5,8,11,[18][19][20][21][22][23][24][25][26][27][28][29][30][31]. Figure 1 shows the flow chart.…”

“…A total of 19 studies consisting of 3592 patients and 3783 knees (MP: 1811 knees, PS: 1972 knees) were included in this meta-analysis, including eight RCTs [18,19,21,22,[25][26][27][28]] and 11 case-control studies [4,5,8,11,20,23,24,[29][30][31][32]. Table 1 shows the baseline characteristics of the included studies.…”

Larger Medial Contact Area and More Anterior Contact Position in Medial-Pivot than Posterior-Stabilized Total Knee Arthroplasty during In-Vivo Lunge Activity

“…Total knee arthroplasty (TKA) is an effective surgical procedure for end-stage knee osteoarthritis in terms of functional restoration of the knee and pain relief [ 1 , 2 , 3 , 4 ]. Despite this, over 20% of patients complained about continuous pain and dissatisfactory function [ 4 ].…”

“…The ball-and-socket medial compartment provides knee stability, and the relatively flat surface on the lateral compartment allows for greater anterior-posterior translation. Multiple studies have reported superior clinical patient outcomes in MP-TKA compared to PS-TKA [ 1 , 15 , 16 , 17 , 18 ]. In contrast, some other studies have shown no difference between the two groups [ 2 , 19 , 20 , 21 ].…”