Quadriceps Muscle Strength Correlates With Serum Vitamin D and Knee Pain in Knee Osteoarthritis
Bibliographic record
Abstract
BACKGROUND: Quadriceps muscle weakness and vitamin D deficiency are associated with knee osteoarthritis (KOA). This study aimed to investigate the relationship between quadriceps muscle strength (QMS) and vitamin D in KOA. METHODS: Patients with KOA aged 40 years and above were studied. QMS was assessed by the dynanometry method and serum 25-hydroxyvitamin D (25-OHD) by the ELISA method. Serum 25-OHD<20 ng/mL was considered as a deficiency. The intensity of knee pain was determined by the Western Ontario and McMaster Universities Osteoarthritis Index Pain Scale. The Pearson test was used for correlation analysis between QMS and serum 25-OHD as well as knee pain. RESULTS: A total of 92 patients (female, 80%) with a mean age of 49.6±11.7 years were studied. QMS was correlated positively with serum 25-OHD (r=0.304, r=9.24%, P=0.005) and negatively with knee pain (r=-0.232, r=5.3%, P=0.034). After adjustment for age, sex, and body mass index, the positive correlation increased to a higher level (r=0.496, r=24.9%, P=0.01). For each 1 ng/mL increase in serum 25-OHD, the value of QMS increased by 14.2%±3.5% (P=0.014). There was no significant correlation between serum 25-OHD and knee pain (P=0.13). CONCLUSIONS: These findings demonstrated a significant correlation between QMS with both serum vitamin D and knee pain, indicating a confounding role for quadriceps muscle in the association between serum vitamin D and osteoarthritis knee pain. On the basis of the findings of this study, vitamin D supplementation may affect pain by strengthening quadriceps muscle in KOA.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".