The impact of obesity on the mid-term outcome of cementless total knee replacement

Abstract

We evaluated 535 consecutive primary cementless total knee replacements (TKR). The mean follow-up was 9.2 years (0.3 to 12.9) and information on implant survival was available for all patients. Patients were divided into two groups: 153 obese patients (BMI > or = 30) and 382 non-obese (BMI < 30). A case-matched study was performed on the clinical and radiological outcome, comparing 50 knees in each group. We found significantly lower mean improvements in the clinical score (p = 0.044) and lower post-operative total clinical scores in the obese group (p = 0.041). There was no difference in the rate of radiological osteolysis or lucent lines, and no difference in alignment. Log rank test for survival showed no significant differences between the groups (p = 0.167), with a ten-year survival rate of 96.4% (95% confidence interval (CI) 92 to 99) in the obese and 98% (95% CI 96 to 99) in the non-obese. The mid-term survival of TKR in the obese and the non-obese are comparable, but obesity appears to have a negative effect on the clinical outcome. However, good results and high patient satisfaction are still to be expected, and it would seem unreasonable to deny patients a TKR simply on the basis of a BMI indicating obesity.

Obesity Has a Negative Impact on Clinical Outcome after Total Knee Arthroplasty

“…Foran et al (19) concluded in their study with 87 knees that any degree of obesity has a negative impact on the outcome of TKA: they found that there was a significant difference in the postoperative Knee Society scores between non-obese and obese patients. Jackson et al (20) reported that obese patients had significantly lower mean improvement in clinical scores after TKA measured by using The Hospital for Special Surgery Knee Rating Score system (HSS). Obesity has also been shown to increase the risk of postoperative complications after knee replacement surgery.…”

All-Polyethylene Tibial Components in Obese Patients Are Associated With Low Failure at Midterm Followup

“…For most obese patients, as for any patient, TKA results in improved pain and function scores with high satisfaction rates [2,12,26,30,33,37,49]. MBT components and modern APT components both have been shown to be successful in the general population; however, the use of APT components specifically in obese patients has not been well studied.…”

“…Studies focusing on the obese patient population show most patients show improvements in outcome scores and are satisfied with TKA [1,2,12,18,19,24,26,30,33,37,43,44,48,49]. However, high body weight amplifies the magnitude of joint load per step and may adversely affect polyethylene wear performance and the rate of aseptic loosening.…”

The Influence of Obesity on the Complication Rate and Outcome of Total Knee Arthroplasty

“…After consensus was reached, twenty studies were included for data analysis. The baseline characteristics and methodology of the included trials are summarized in the Appendix [6][7][8][9][10][11][12][13][14][15][16][22][23][24][25][26][27][28][29][30] . Data regarding the presence of any infection were extracted from the studies in which this outcome was reported; in addition, deep and superficial infections were analyzed separately in studies Flowchart showing identification of the included studies.…”