The anatomy of osteoarthritic joint pain

Abstract

The anatomical understanding of the pain generators in osteoarthritis (OA) is incomplete and the teaching about these pain generators in medical school anatomy/histology courses is minimal. This review covers the nociceptive innervation of synovial joints for the purposes of teaching. Studies that discuss the presence of neuropeptides involved in pain, such as Substance P (SP) and calcitonin-gene-related peptide, are the focus of this review. Nociceptive free-nerve endings and SP staining nerves are found in the accessory ligaments, synovium, subchondral bone, menisci, and periosteum. The vasculature may also play a role in pain generation through vasospasm or ischemia, but this has yet to be proven. Joint denervation may relieve joint pain showing that it is indeed articular nerves that are carrying pain impulses but denervation does not identify the precise source of the pain. It remains unclear which of the anatomical loci of pain generation are primary in OA and if sources of pain vary in different patients and in different joints.

Correlations between inflammatory cytokines, muscle damage markers and acute postoperative pain following primary total knee arthroplasty

“…Thirdly, no control group, such as unicompartmental knee arthroplasty or minimally invasive approach, was established, and the joint function was not reported in this study. Finally, other confounding factors, such as fear or anxiety, articular nerves, implant type, and anticoagulant used for prophylaxis of postoperative venous thromboembolism [48–50], might also affected the acute postoperative pain following TKA.…”

Skin penetration and tissue permeation after topical administration of diclofenac

“…There are no nociceptors in articular cartilage, the main structure affected morphologically in OA. Thus, the pain that occurs when the cartilage wears away must instead originate from other structures within the joint, such as the synovial membrane or tissue, bone, or periarticular muscles and ligaments, for example 17,[24][25][26][27] . Nociceptors are abundant in many articular tissues 21 that are in contact with the intraarticular environment 28 .…”

Osteochondral tissue regeneration using a bilayered composite hydrogel with modulating dual growth factor release kinetics in a rabbit model

“…Articular cartilage is a flexible connective tissue that facilitates the articulation of bone in major synovial joints via the dissipation of friction and physiological compressive forces [1–5]. With a limited endogenous ability for self-repair, damaged cartilage as a result of disease or trauma oftentimes leads to premature arthritis.…”