Medicated oils are used in Ayurveda for osteoarthritis, osteoporosis, or bone healing after fractures. Here’s a possible explanation of their therapeutic mechanism.

1. Transdermal Absorption: The bioactive compounds in medicated oils, like essential oils and fatty acids, penetrate the skin’s outer layer (stratum corneum) by dissolving into its lipid matrix. This allows the oils to move deeper into the dermis where blood vessels reside.


2. Entry into the Bloodstream: Once in the dermis, the oils' compounds are absorbed into nearby capillaries or the lymphatic system, entering the bloodstream for systemic distribution. Lipophilic molecules can passively diffuse into blood vessels and circulate throughout the body.


3. Targeting Bone Tissue: Once in the bloodstream, the active compounds from the medicated oil are transported to bone tissue. Bone is a dynamic tissue, constantly undergoing remodeling via osteoclasts (cells that break down bone) and osteoblasts (cells that build bone). 

Key Mechanisms:
- Selective uptake by bone cells: Osteoblasts and osteoclasts have receptors for certain molecules, such as polyphenols and alkaloids, found in medicinal plants. These receptors mediate the uptake of bioactive compounds into bone cells.

- Inhibition of osteoclast activity: Some plant compounds, such as flavonoids and tannins, inhibit osteoclasts, reducing breakdown of bone tissue, which is particularly important in conditions like osteoporosis.

- Stimulation of osteoblast activity: Other compounds, such as saponins and phytoestrogens, stimulate osteoblasts, promoting the deposition of new bone matrix and enhancing bone regeneration.


4. Bone Matrix Repair and Rejuvenation: The therapeutic oils are rich in bioactive compounds that facilitates the healing of microfractures, 
re-mineralization and restore the structural integrity of bone tissue.

Key Mechanisms: 
- Enhanced collagen synthesis: Plant-derived molecules like proanthocyanidins and curcuminoids can stimulate fibroblasts and osteoblasts to produce collagen, a key protein in the bone matrix.

- Calcium-phosphate deposition: Certain minerals in Ayurvedic oils, or their capacity to improve calcium absorption, promote the deposition of calcium and phosphate ions in the bone matrix, which is crucial for bone strength and healing.

- Anti-inflammatory action: Many oils contain anti-inflammatory compounds, such as sesquiterpenes (e.g., β-caryophyllene) and curcumin, that reduce pro-inflammatory cytokines (e.g., TNF-α, IL-1β). By lowering inflammation, these oils prevent further tissue damage and create an environment conducive to healing.

5. Reduction of Oxidative Stress: Plant-derived antioxidants, like flavonoids, neutralize reactive oxygen species (ROS), protecting bone cells from oxidative damage. This helps maintain osteoblast function and supports continuous bone healing.