Relationship between decreased lower extremity muscle mass and knee pain severity in both the general population and patients with knee osteoarthritis: Findings from the KNHANES V 1-2

Abstract

ObjectiveTo identify the prevalence of and risk factors for knee pain and radiographic knee osteoarthritis (RKOA) and to investigate the relationship between decreased lower extremity muscle mass (DLEM) and knee pain severity.MethodsUsing data from the Korea National Health and Nutrition Examination Survey, 3,278 participants who were ≥50 years old and who underwent dual x-ray absorptiometry, plain knee radiographs and completed a knee pain questionnaire were enrolled. Lower extremity muscle mass (LEM) was defined as the sum of the fat-free soft tissue mass of the legs, and lower extremity muscle mass index (LMI) was calculated as LEM/body weight (%). DLEM was defined as an LMI more than two standard deviations below the mean of a gender-matched young reference group. Categorical variables were presented as numbers (weighted %).ResultsThe prevalence of knee pain and RKOA were 22% (n = 721) and 34.7% (n = 1,234), respectively. Multivariate logistic regression analysis showed being female (OR 2.15, 95% CI 1.67–2.79), older (OR 1.03, 95% CI 1.01–1.04), less educated (OR 1.72, 95% CI 1.09–2.71), stiffness (OR 16.15, 95% CI 12.04–21.66), bed rest (OR 2.49, 95% CI 1.81–3.43), RKOA (OR 2.20, 95% CI 1.78–2.74) and DLEM (OR 1.54, 95% CI 1.09–2.17) were associated with knee pain. Participants with simultaneous RKOA and DLEM complained of more severe pain (pain score 7.18 ± 2.48) than those with knee pain without RKOA or DLEM (5.02 ± 2.44), those with only RKOA (6.29 ± 2.50), or those with only DLEM (6.78 ± 2.18) (P<0.001). These results remained after multivariate analyses of variance (MANOVAs).ConclusionThe prevalence of knee pain and RKOA were 22% and 34.7%, respectively, in the general Korean population. DLEM was an independent risk factor for knee pain and it was associated with increased pain severity, regardless of RKOA.

Impact of sarcopenia on rehabilitation outcomes after total knee replacement in older adults with knee osteoarthritis

“…Aging-related muscle mass deterioration was identified to be associated with the severity of knee pain, 49 particularly in older women with radiographically mild KOA. 50 For mild KOA (K-L grade = 2), appendicular muscle mass relative to body weight was reported to be significantly lower in patients with knee pain than in those without knee pain, whereas no such difference was noted for moderate-to-severe KOA (K-L grade ⩾3).…”

Low handgrip strength is closely associated with chronic low back pain among women aged 50 years or older: A cross-sectional study using a national health survey

“…In particular, it has been reported that exercise for 2 days or more per week on nonconsecutive days significantly reduces LBP [ 4 ][ 5 ]. The relation of low skeletal muscle mass of the extremities to other musculoskeletal pain has been reported [ 9 ][ 20 ]. These reports have indicated that low muscle mass of the extremities is associated with knee pain [ 20 ] and neck or shoulder pain [ 9 ], but is not related to LBP.…”

“…The relation of low skeletal muscle mass of the extremities to other musculoskeletal pain has been reported [ 9 ][ 20 ]. These reports have indicated that low muscle mass of the extremities is associated with knee pain [ 20 ] and neck or shoulder pain [ 9 ], but is not related to LBP. To our knowledge, only one study analyzed the direct relationship between trunk muscle strength and LBP and showed the association between isometric and isokinetic extensor weakness and LBP [ 7 ].…”

Evaluation of the effect of cooling strategies on recovery after surgical intervention

“…Investigations of Sattler et al 35 and Wang et al 40 showed a significant difference in muscle cross section of the vastus medialis in painful compared with contralateral painless limbs. Also, Cheon et al investigated the relationship between decreased lower extremity muscle mass and knee pain intensity in both the general population and patients with knee osteoarthritis 41. They found that a decreased lower extremity muscle mass was an independent risk factor for knee pain and it was associated with increased pain intensity, regardless of radiographic knee osteoarthritis.…”

“…However, probably not only the reduced pain has a positive influence on the muscle cross section, but also the associated increased physical activity. An increased physical activity induces a hypertrophy of lower limb muscle, especially of vastus medialis, which positively affects reduction in the pain level and pain perception of the patients 35 41. Also stress and depression, which are often associated with chronic pain, can be positively affected by physical exercise,42 43 which further promotes the healing process.…”