[Patient satisfaction and muscle torque after total knee replacement in dependence on body mass index]

Abstract

Aim: In a monocentric study, we investigated patient satisfaction, clinical outcome and isokinetic muscle torque in dependence on the body mass index (BMI) in the mid-term outcome after total knee arthroplasty.

Patients and methods: A group-matched study with two groups (each 40 knee arthroplasties in 40 patients) with a normal body mass index (BMI 20-25) and above 25 was conducted. The groups were matched for sex, diagnosis and age. Satisfaction, HSS score and isokinetic torque parameters with the Cybex 340 system were measured.

Results: There were no differences in the demographic data except for BMI. The HSS score was significantly lower in the overweight group (p = 0.04). Also there were more patients with an HSS score below 60 (bad result) in the group with the higher BMI (0 vs. 9, p = 0.002). Only one patient was not satisfied in the normal weight group, whereas 9 patients in the group BMI > 25 were not satisfied (p = 0.014). No differences between the groups could be found in maximum torque, work and power.

Conclusion: The patient satisfaction was much lower in patients with BMI higher than 25. There were no differences between the groups in isokinetic torque parameters.