Key Measurement Steps
Identify Anatomical Landmarks
Sit with the knee bent at 90°, locate the center of the patella (kneecap) as the reference point.
Mark two measurement positions:
PP1 (Superior Patellar Pole): 10 cm above the top edge of the patella (for sleeves covering the quadriceps tendon).
PP2 (Inferior Patellar Pole): 5 cm below the bottom edge of the patella (for sleeves targeting patellar tendon stabilization).
Precise Circumference Measurement (Use a flexible tape measure)
Axial Resting Circumference:
Measure around the leg at PP1/PP2 with the muscle relaxed (no active contraction).
Dynamic Contracted Circumference (for athletic use):
Perform a single-leg mini-squat (30° knee flexion), measure the circumference at the peak muscle bulge.
Cross-Validate Data
Compare resting vs. dynamic values:
Difference ≤5% → Choose the resting size
Difference >5% → Use the average value and prioritize elastic fabrics (e.g., ≥25% spandex).
Size Selection Matrix (Based on International Biomechanics Standards)
| Knee Circumference (cm) | Use Case | Compression Level (mmHg) | Material Stretch Recommendation |
|---|---|---|---|
| 30-35 | Sedentary edema reduction | 10-15 (Grade I) | Unidirectional elastic knit |
| 35-40 | Daily sports protection | 15-20 (Grade II) | 4-way stretch weave |
| 40-45 | High-impact training | 20-30 (Grade III) | Gradient compression technology |
Fit Verification Checklist
Pressure Distribution Test
Perform five squats after wearing the sleeve. Check:
No vertical wrinkles → Indicates even tension distribution.
Patellar opening remains centered → Prevents friction syndromes.
Peripheral Circulation Check
Observe toe capillary refill time after 20 minutes of wear:
Normal: Color returns within <2 seconds after pressure.
Warning: >3 seconds → Size up immediately.
Motion Compatibility Test
Perform 3 minutes of high knees. Check for:
Sleeve slippage >2 cm → Switch to silicone-grip models.
Popliteal fossa (back of knee) fabric bunching → Choose sleeves with rear cutouts.
