It may be possible to apply tensile strain to articular cartilage to induce endochondral ossification there thereby inducing height growth.
Effects of cyclic tensile strain on chondrocyte metabolism: a systematic review.
“Chondrocytes reorganize the extracellular matrix of articular cartilage in response to externally applied loads. Thereby, different loading characteristics lead to different biological responses. Despite of active research in this area, it is still unclear which parts of the extracellular matrix adapt in what ways, and how specific loading characteristics affect matrix changes. This review focuses on the influence of cyclic tensile strain on chondrocyte metabolism in vitro. It also aimed to identify anabolic or catabolic chondrocyte responses to different loading protocols. The key findings show that loading cells up to 3% strain, 0.17 Hz, and 2 h, resulted in weak or no biological responses. Loading between 3-10% strain, 0.17-0.5 Hz, and 2-12 h led to anabolic responses; and above 10% strain, 0.5 Hz, and 12 h catabolic events predominated{catabolic responses doesn’t necessarily mean bad for height growth}. However, this review also discusses that various other factors are involved in the remodeling of the extracellular matrix in response to loading, and that parameters like an inflammatory environment might influence the biological response.”<-3% strain is quite high but that’s for bone for cartilage it may be different.
“cartilage compression exposes the chondrocyte to compressive forces, to osmotic pressure, to fluid flows and also to tensile forces”<-lateral compression such as via lateral loading of the articular cartilage has potential to induce tensile forces.
“after loading with CTS, cells exhibited a more elongated cell shape and aligned perpendicular to the loading direction”
Collagen Type I was upregulated by CTS which could indicated endochondral ossification.
“Fibronectin connects collagen fibers and other ECM proteins. It is linked to the cell membrane through integrins and might transmit forces from the ECM to the chondrocyte. CTS at 7%, 0.33 Hz and 0.5 Hz, for 4, 12 and 24 h increased the fibronectin mRNA levels in comparison to non-loaded chondrocytes”
“7% CTS for 4 h at 0.33 Hz elevated the expression of IGF-1 and IGF-2. The mRNA expression of TGF-β1 was increased by several loading protocols ranging from strains of 5–12%, from 12–48 h and at frequencies of 0.05 and 0.5 Hz”
According to CYCLIC TENSILE STRAIN AND CYCLIC HYDROSTATIC PRESSURE DIFFERENTIALLY REGULATE EXPRESSION OF HYPERTROPHIC MARKERS IN PRIMARY CHONDROCYTES , tensile strain encourages endochondral ossification whereas hydrostatic pressure encourages chondrogenesis.
