Quantifying Region-Specific Elastic Properties of Distal Femoral Articular Cartilage: A Shear-Wave Elastography Study

Abstract

Knee osteoarthritis is a disease with the degeneration of articular cartilage as its main feature. Cartilage thickness cannot become a single index to evaluate cartilage degeneration, so it is essential to also evaluate the stiffness. The purposes were as follows: (1) to examine test-retest reliabilities of the elastic modulus measurement in distal femoral articular cartilage (FAC) and compare the changes in specific-regional of distal FAC, (2) to explore the difference in distal FAC stiffness and thickness between the dominant and nondominant sides, and (3) to examine the correlation between the elastic properties of cartilage and the thickness of cartilage. Twenty healthy participants were recruited. The stiffness of distal FAC at the lateral femoral condyle (LFC), medial femoral condyle (MFC), and intercondylar notch (IN) was quantified using shear-wave elastography (SWE). Intra- and interrater reliabilities were excellent for measuring the stiffness of distal FAC (ICC: 0.83-0.98). About a 50% increase in the stiffness of LFC (40.78 kPa) was found when compared with IN (21.82 kPa) and MFC (18.34 kPa). No significant difference was found between the dominant and nondominant sides in distal FAC stiffness and thickness. There was no correlation between the stiffness and thickness of the distal FAC. In conclusion, SWE can quantify the stiffness of the distal FAC.

Sonoelastography: A powerful technique in musculoskeletal imaging

“…Similar greater sensitivity of sonoelastography versus grayscale US for early stages of tendinopathy have been reported in the Achilles, quadriceps, biceps, supraspinatus, and other tendons 9,14–17 . Sonoelastography has also been applied to osteoarthritic cartilage, the transverse ligament in carpal tunnel syndrome, myopathies, ligaments, rheumatoid synovitis, methotrexate hepatotoxicity (important in rheumatology), meniscal disease, trigger finger, and musculoskeletal tumors with similar changes in elasticity of the relevant tissue with variable sensitivity and specificity for pathology versus alternative imaging methods 14–25 …”

“…The low cost, convenience, noninvasive nature, lack of ionizing radiation, direct relevance to palpable anatomy, point‐of‐care applicability, and increasing number of applications indicate that US will only increase in use in musculoskeletal medicine 1–4 . Sonoelastography is another powerful method available to observe the musculoskeletal system, and appears particularly valuable in detecting early tendinopathies, areas of myopathy suitable for biopsy, pursuing complaints of localized musculoskeletal pain, analyzing soft tissue masses, and research applications in musculoskeletal medicine 14–25 . Shear wave elastography in particular permits rapid quantitative assessments of musculoskeletal structures and will be particularly valuable at the beside, in research studies and clinical trials, and in monitoring disease presence, progression, and response to therapy, especially in muscle and tendon disease.…”

“…9,[14][15][16][17] Sonoelastography has also been applied to osteoarthritic cartilage, the transverse ligament in carpal tunnel syndrome, myopathies, ligaments, rheumatoid synovitis, methotrexate hepatotoxicity (important in rheumatology), meniscal disease, trigger finger, and musculoskeletal tumors with similar changes in elasticity of the relevant tissue with variable sensitivity and specificity for pathology versus alternative imaging methods. [14][15][16][17][18][19][20][21][22][23][24][25] US is increasingly becoming an extension of the physical examination in musculoskeletal medicine. 1 The low cost, convenience, noninvasive nature, lack of ionizing radiation, direct relevance to palpable anatomy, point-of-care applicability, and increasing number of applications indicate that US will only increase in use in musculoskeletal medicine.…”

“…[1][2][3][4] Sonoelastography is another powerful method available to observe the musculoskeletal system, and appears particularly valuable in detecting early tendinopathies, areas of myopathy suitable for biopsy, pursuing complaints of localized musculoskeletal pain, analyzing soft tissue masses, and research applications in musculoskeletal medicine. [14][15][16][17][18][19][20][21][22][23][24][25] Shear wave elastography in particular permits rapid quantitative assessments of musculoskeletal structures and will be particularly valuable at the beside, in research studies and clinical trials, and in monitoring disease presence, progression, and response to therapy, especially in muscle and tendon disease. It is anticipated that sonoelastography will increase in specificity, sensitivity, depth of imaging, and applications as the technology of this US method becomes increasingly sophisticated.…”

An Update on Clinical Utility of Musculoskeletal Ultrasonography in Knee Osteoarthritis

“…29,35 As the stiffness is different between the lateral femoral and the medial femoral cartilages, we should compare the same region in study. 36 In a report, elastography exhibited a color change from blue to red in pathologic cartilage, whereas there is only blue color coding in healthy cartilage, in which color change from blue to red represents increased strain ratio and softening. Those ultrasound findings were consistent with MRI results, and proving that elastography is a simple and feasible method to differentiate healthy cartilage from pathologic cartilage.…”