Non-terminal animal model of post-traumatic osteoarthritis induced by acute joint injury

Abstract

Objective Develop a non-terminal animal model of acute joint injury that demonstrates clinical and morphological evidence of early post-traumatic osteoarthritis (PTOA). Methods An osteochondral (OC) fragment was created arthroscopically in one metacarpophalangeal (MCP) joint of 11 horses and the contralateral joint was sham operated. Eleven additional horses served as unoperated controls. Every 2 weeks, force plate analysis, flexion response, joint circumference, and synovial effusion scores were recorded. At weeks 0 and 16, radiographs (all horses) and arthroscopic videos (OC injured and sham joints) were graded. At week 16, synovium and cartilage biopsies were taken arthroscopically from OC injured and sham joints for histologic evaluation and the OC fragment was removed. Results Osteochondral fragments were successfully created and horses were free of clinical lameness after fragment removal. Forelimb gait asymmetry was observed at week 2 (P=0.0012), while joint circumference (P<0.0001) and effusion scores (P<0.0001) were increased in injured limbs compared to baseline from weeks 2 to 16. Positive flexion response of injured limbs was noted at multiple time points. Capsular enthesophytes were seen radiographically in injured limbs. Articular cartilage damage was demonstrated arthroscopically as mild wear-lines and histologically as superficial zone chondrocyte death accompanied by mild proliferation. Synovial hyperemia and fibrosis were present at the site of OC injury. Conclusion Acute OC injury to the MCP joint resulted in clinical, imaging, and histologic changes in cartilage and synovium characteristic of early PTOA. This model will be useful for defining biomarkers of early osteoarthritis and for monitoring response to therapy and surgery.

Pro-inflammatory cytokines and structural biomarkers are effective to categorize osteoarthritis phenotype and progression in Standardbred racehorses over five years of racing career

“…This is the first study in which the long-term consequences of an impact joint injury have been evaluated in STBRs with spontaneous PTOA, regularly trained after a rehabilitation period, and using biomarkers to assess disease activity. Previous studies focused on OA biomarkers in experimental horse models spread their observations to a limited number of weeks following the acute joint injury [2, 7, 27, 38–40]. …”

“…Considering animal models of PTOA, racehorses sustaining repetitive impact joint injuries, during their athletic career, are likely to develop DJD shortly after the initial inflammatory event affecting the joints [2, 4, 6, 7]. This progression was bound to occur at a much faster rate than in humans [22, 23], although there are currently not enough investigations and consensus about this statement.…”

Osteochondral fragments of the pastern joint at the origin of the collateral ligament of the distal sesamoid bone: performance after arthroscopic removal (2000–2015)

“…While lesions described in this report also affected young horses and were occasionally found bilaterally, an aggressive proliferative reaction is not typical of a developmental cause. Indeed, such reaction would be more consistent with trauma and degeneration (Figures and ) . Traumatic fragments are commonly found in other joints in yearling horses on survey radiographs, without a history of athletic training or a traumatic incident .…”

“…The lesion was most distinct on the dorsolateralpalmaro/plantaromedial oblique view in 29 of 39 cases. The mean fragment size was 9.9 mm (median, 9.0; range, [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. With arthroscopic findings as the reference, the parent bone of the fragment was readily determined from radiographic examination in 24 of 39 cases (Figure 2).…”

Circumferential hoof clamp method of lameness induction in the horse

“…Horses included four mares and four geldings weighing 487-595 kg (mean ± standard deviation, SD, 537 ± 37 kg). Prior to their inclusion, horses were used as sound, control horses for another study, in which they were acclimated to force plate examinations (Boyce et al, 2013). Experimental procedures were approved by the University of Minnesota Institutional Animal Care and Use Committee (IACUC; protocol #1007A86632, date of approval 12 August 2010).…”