Allows gliding function where sheaths are not present. Vascular Supply 1. Vascular supply dependent on location within tendon and presence or absence of sheath. Both intrinsic and extrinsic vascular supply. Paratenon are most vascular, most vessels run parallel to long axis of tendon.
Capillaries surround individual collagen bundles within the endotenon.
Although relatively acellular, tendons must maintain basal metabolism to provide strength and elasticity. Tendon regenerated every 6 months. Only aerobic metabolism, ischemia may occur if tendon is overworked. Initial inflammatory response with deposition of fibrin and influx of platelets, neutrophils, and macrophages. Fibroblastic and capillary invasion originating from paratenon.