Does Obesity Influence on the Functional Outcomes of a Total Knee Arthroplasty?

BACKGROUND: The objective of this study was to compare the total knee arthroplasty (TKA) functional outcomes and quality of life of obese and non-obese patients. METHODS: Prospective comparative study, including all patients underwent TKA in a single centre. Patients were divided into three groups: Group 1 (Gr.1) BMI <30 kg/m2, Group 2 (Gr.2) BMI ≥ 30 kg/m2 and <35 kg/m2 and Group 3 (Gr.3) BMI ≥35 kg/m2. The Knee Society score (KSS) and SF-36 scores were obtained preoperatively and at 5 years of follow-up. RESULTS: A total of 689 patients were included (72.2 ± 7 years, 76.3 % women). Overall, pre- and post-operative values of SF-36 were lower for the obese group. However the improvement obtained in the three groups was similar in all the sub-scales of the SF-36 score. KSS values were higher in the non-obese group in both periods. However the improvement obtained in this score in the three groups was similar (Gr.1; 70.21 ± 34.31, Gr.2; 66.53 ± 34.93, Gr.3; 60.94 ± 38.47, n.s.). CONCLUSIONS: Although non-obese patients obtained better functional and reported quality of life scores than obese patients, there were no differences in the gain of quality of life and knee functionality between both groups at 5-years of follow-up. This is one of the largest series in a single centre published in literature and confirms the results obtained by other authors. Taking into account the different outcomes obtained, surgery should not be denied to patients that are obese, given that they obtained similar benefit than non-obese patients.

The magnetic resonance aspect of a polyurethane meniscal scaffold is worse in advanced cartilage defects without deterioration of clinical outcomes after a minimum two-year follow-up.

BACKGROUND: Meniscal scaffolding is thought to provide functional improvement and to prevent cartilage degeneration. Advanced chondral injuries might damage the scaffold structural properties. OBJECTIVE: To evaluate the influence of different degrees of articular chondral injuries on the imaging aspect of a polyurethane meniscal scaffold (Actifit®). METHODS: Fifty-four patients operated on with an Actifit® were studied. The status of the articular cartilage in the involved compartment was classified according to ICRS. The characteristics of the implant were evaluated in MRI with the Genovese score. Functional scores included WOMET, IKDC and Kujala scores. The Genovese score was correlated with the degree of chondral injury and functional results. RESULTS: The mean follow-up was 39 months (range 25-63). Additional procedures were performed in 69.5%. There were 19 patients without chondral injuries and 14 with grade 1, 10 with grade 3 and eight with grade 4 chondral lesions. The morphology and size of the implant on MRI scanning were worse with a higher degree of chondral injury (p=0.023). WOMET, IKDC and Kujala improved from 36.2SD ±7.6, 32.3SD ±13.5 and 39.2SD ±8.1 to 75.8SD ±12.9 (p=0.02), 75.5SD ±15.4 (p=0.03) and 85.6SD ±13.4 (0.042), respectively. There was no relationship between the severity of chondral injury and functional scores. CONCLUSIONS: Patients without chondral injuries showed a better MRI aspect of the polyurethane scaffold in terms of size and morphology. By optimizing biomechanics, in particular the implantation of a meniscal substitute, significant pain relief and functional improvement were observed after a minimum two-year follow-up. LEVEL OF EVIDENCE: Therapeutic case series; level 4.