Neurovascular invasion at the osteochondral junction and in osteophytes in osteoarthritis

Abstract

Background: Normal adult articular cartilage is thought to be avascular and aneural. Objective: To describe neurovascular structures at the osteochondral junction and in osteophytes in tibiofemoral osteoarthritis (OA) displaying a range of severity of cartilage changes. Methods: Articular surfaces were obtained from 40 patients at total knee joint replacement surgery for tibiofemoral OA (TKR) and seven patients post mortem (PM). Antibodies directed against CD34 (vascular endothelium), protein gene product 9.5 (pan-neuronal marker), substance P and calcitonin gene-related peptide (sensory nerves) and C-flanking peptide of neuropeptide Y (sympathetic nerves) were used to localise blood vessels and nerves by immunohistochemistry. Severity of OA cartilage changes was graded histologically. Results: TKR and PM samples displayed a range of OA cartilage changes including tidemark breaching by vascular channels. Sympathetic and sensory nerves were both present within vascular channels in the articular cartilage, in both mild and severe OA. Perivascular and free nerve fibres, and nerve trunks were observed within the subchondral bone marrow and within the marrow cavities of osteophytes. Sensory and sympathetic nerves displayed similar distributions in each region studied. Conclusion: Vascularisation and the associated innervation of articular cartilage may contribute to tibiofemoral pain in OA across a wide range of structural disease severity.

Efficacy of zoledronic acid in treatment of teoarthritis is dependent on the disease progression stage in rat medial meniscal tear model

“…Osteochondral vascular density increased with increasing cartilage deterioration severity and clinical disease activity scores [36] . Sensory nerves were present within vascular channels at the osteochondral junction in OA [37] . Therefore subchondral nerves may be exposed to painful stimuli in OA, which would Acta Pharmacologica Sinica npg lead to weight-bearing pain, the most common symptom in OA patients [3] .…”

Grape seed proanthocyanidin extract ameliorates monosodium iodoacetate-induced osteoarthritis

“…Suri et al sug-gested that vascularization of the damaged articular cartilage is accompanied by innervation, which contributes to pain (Suri et al, 2007). GSPE has been reported to be effective in inhibiting angiogenesis (Lu et al, 2009).…”

Localization of vascular endothelial growth factor during the early stages of osteochondral regeneration using a bioabsorbable synthetic polymer scaffold

“…24 This osteochondral angiogenesis may potentiate joint damage by stimulating ossification in the OA cartilage. [25][26][27][28][29] Furthermore, VEGF may directly increase catabolic pathways in cartilage tissue by activating matrix metalloproteinase and reducing tissue metalloproteinase inhibitors, additionally to indirect effect such as osteochondral angiogenesis. 15,16,30,31 VEGF was also reported to play a critical role in endochondral ossification.…”