Isometric and isokinetic quadriceps strength in gonarthrosis; Inter-relations between quadriceps strength, walking ability, radiology, subchondral bone density and pain

Abstract

Patients with osteoarthrosis suffer from disability and pain. We measured isokinetic and isometric peak torque in 20 women with gonarthrosis (GA) and in 26 healthy controls. Relationships between muscle strength, walking and stair climbing time, pain level and pain disability scores as assessed by the patients using an extensive questionnaire, radiological changes and subchondral sclerosis expressed as bone mineral density (BMD, g/cm2) of the proximal tibia were studied. Precision errors of the torque measurements in both GA patients and controls were approximately 6%. In the GA patients, isokinetic and isometric quadriceps strength was reduced by 40 and 15% (p < 0.01) respectively, and walking and stair climbing time was increased by 30% (p < 0.005). Isokinetic strength was a better predictor of pain level and pain disability scores than isometric strength and radiological stage. Walking time and stair climbing time were not associated with quadriceps strength, pain level, pain disability scores or radiological changes. Subchondral BMD was not predictive of pain. The study suggests that quadriceps strength assessed by isokinetic dynamometry in GA is a reliable measurement. Isokinetic strength was pronouncedly reduced compared to isometric strength and was a more important predictor of pain and pain disability than isometric strength. These findings should be taken into consideration when planning exercise studies and programmes in GA.

Association of Thigh Muscle Strength With Knee Symptoms and Radiographic Disease Stage of Osteoarthritis: Data From the Osteoarthritis Initiative

“…Further, an effect of leg dominance on thigh muscle strength was not supported by the findings of Ditroilo et al (42). It has been reported previously that thigh muscle weakness affects gait (43) and knee function (44) and is an important determinant of functional disability (45,46). The current results are suggestive of thigh muscle weakness being caused by pain but not by radiographic changes per se (47).…”

Assessment of Isokinetic Muscle Strength in Women Who Are Obese

“…7,48 Moreover, isokinetic strength correlates significantly with functionality scores in gonarthrosis and patients with low back pain. 24,42 However, reference data of isokinetic peak force of the thigh and trunk have not, to our knowledge, been reported for individuals who are obese. Several methodological problems arise when testing those patients isokinetically (ie, appropriate fixation of the trunk, weighing of the trunk to perform gravity correction, 35 the inertia effects of the body when testing at high velocities, 6,18 pain inhibition due to osteoarthritis, 26 and cardiovascular problems 40 ).…”

Impact of Knee Osteoarthritis on Muscle Force, Function and Quality of Life

“…17 Furthermore, the patients with a more significant impairment in the side affected by osteoarthritis by comparison with the healthy side in isometric contraction as well as in concentric contraction. 18,19 Diraçoglu et al 20 Consider that muscular weakness in lower limbs is one of the most important causes of locomotor dysfunction and invalidity in patients suffering from knee osteoarthritis. In a comparative study involving 51 patients with knee osteoarthritis and 43 healthy subjects, the manual muscle testing of the quadriceps was, for the knee osteoarthritis affected patients, of 4/5 for 6 knees and of 5/5 for 96 knees, whereas in the control group only 2 legs were rated at 4/5 and 84 knees had a muscular strength rated at 5/5 (p=0.22).…”