FRI0720-HPR The effect of overweight on knee proprioception inpatients with knee prosthesis due to knee osteoarthritis
Authors: M. Eymir, B. Ünver, V. Karatosun
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background:</h3> Total knee arthroplasty (TKA) has been established as a valuable procedure for the management of patients with disabling knee osteoarthritis, and the rates of elective TKA are increasing steadily each year. Being overweight is a risk factor for osteoarthritis of weight-bearing joints, such as the knee joint. In literature some studies about obesity and lower limb biomechanics found that obesity will change a person's gait model to adapt weight loading. Also it is stated that obese people have to reorganized their neuromuscular function to reduce the total load on the knee joint. Therefore, the ability to reorganize neuromuscular function may be a more insightful risk factor for knee osteoarthritis. There is not any study research on the effect of overweight on knee proprioception in patients with TKA due to osteoarthritis. <h3>Objectives:</h3> The aim of this study was to determine the effect of the overweight on knee joint proprioception in patients with TKA due to osteoarthritis. <h3>Methods:</h3> The study group consisted of 61 patients, who underwent primary TKA because of arthrosis were stratified by obesity status using pre-operative BMI. Non-obese (n=23, mean age; 67.60±8.48 years) subjects were those with BMI &lt;30 kg/m2 and obese (n=38, mean age; 63.81±9.21 years) subjects were those with BMI ≥30 kg/m2. Patients were evaluated regarding knee proprioception (in knee joint angle 15°, 30° and 60°), knee function score (Hospital for Special Surgery (HSS) score), pain (Numeric Pain Rating Scale (NPRS)), knee range of motion, length of hospital stay, the day of knee flexion angle achieved 70 degrees, quality of life (Short-Form 12 Health Survey (SF-12)). Functional activities were evaluated using the Iowa Level of Assistance Scale and walking speed was evaluated using the Iowa Ambulation Velocity Scale. Patients were evaluated preoperatively and at discharge. All patients underwent the same rehabilitation program. <h3>Results:</h3> When the patients' proprioceptive acuity in knee joint angle 30° were compared between groups, while there were statistically differences preoperatively (p=0.007), there were not differences after surgery (p&gt;0.05). When the proprioceptive acuity measured before and after surgery were compared in knee joint angle 15°, 60°, there were not differences (p&gt;0.05) between groups. It was determined that; the non-obese group had better results in terms of length of hospital stay, the day of knee flexion angle achieved 70 degrees and both pre-/postoperative knee flexion degree (p&lt;0.05, for all). There were no statistical differences in the pain degree, HSS score, IOWA help level and IOWA walking speed, SF-12 score between groups before and after TKA (p&gt;0.05). <h3>Conclusions:</h3> There were not differences in knee proprioception between groups after surgery (p&gt;0.05). The deficits in joint position sense in patients with TKA may be due to factors other than the BMI level (being overweight). On the other hand, obesity had negative effects on inpatient rehabilitation outcomes following TKA due to osteoarthritis. These results suggest that the rehabilitation after TKA focused on reducing hospital stay, the day of knee flexion angle achieved 70 degrees and improving knee flexion degree could be important to enhance the potential benefits of the patients' outcomes, and could be important to reduce the payment in rehabilitation hospitals. <h3>Disclosure of Interest:</h3> None declared