Anne-Archard N, Martel G, Fogarty U, Richard H, Beauchamp G, Laverty S
Comparative Orthopaedic Research Laboratory, Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Quebec, Canada.
Irish Equine Centre, Johnstown, Co Kildare, Ireland.
Equine Vet J. 2019 Jan;51(1):115-122. doi: 10.1111/evj.12980. Epub 2018 Jul 13.
The aetiology of equine metacarpal condylar fractures is not completely understood and a developmental cause has been postulated.
To investigate the subchondral bone trabecular microarchitecture of the lateral parasagittal groove and condyle in equine neonates and its adaptation with maturation and athletic activity.
Ex vivo observational study.
Distal metacarpi of neonates, yearlings and adult racehorses (n = 24) were harvested. Dorsal and palmar frontal histological sections, containing the lateral parasagittal groove and condyle, were studied. The sections were digitalised and subchondral trabecular bone quantity and quality parameters and trabecular orientation in the frontal plane were measured.
Trabecular spacing and length were greater (P = 0.004 and P = 0.0005 respectively) whereas bone fraction, trabecular number and connectivity were all lower (P = 0.0004, P = 0.0001 and P = 0.001 respectively) in the lateral parasagittal groove compared with the condyle in neonatal foals. Trabecular thickness and bone fraction increased with age in racehorses and trabecular spacing decreased. The predominant trabecular orientation had a consistent pattern in neonates and it changed with maturity and the cumulative effect of racing at all the ROIs except for the palmar lateral parasagittal groove that retained a more 'immature' pattern.
Samples were investigated in 2D. 3D processing could have provided more information.
Already at birth there are striking differences in the subchondral bone trabecular microarchitecture between the lateral parasagittal groove and condyle in foals. Adaptation of trabeculae is confirmed with maturity in racehorses, with the greatest adaptation measured in bone quantity parameters. The trabecular orientation had a unique and more immature orientation pattern in the lateral palmar parasagittal grooves in adult racehorses and may reflect a weaker structure at this site.
马掌骨髁骨折的病因尚未完全明确，有研究推测其可能与发育因素有关。
研究马驹侧矢状旁沟和髁的软骨下骨小梁微结构，以及其随成熟度和运动活动的适应性变化。
离体观察性研究。
采集新生马驹、一岁龄马和成年赛马的掌骨远端（n = 24）。对包含侧矢状旁沟和髁的背侧和掌侧额状面组织学切片进行研究。将切片数字化，测量软骨下骨小梁的数量和质量参数以及额状面内小梁的方向。
与新生马驹的髁相比，侧矢状旁沟的小梁间距和长度更大（分别为P = 0.004和P = 0.0005），而骨量分数、小梁数量和连接性均更低（分别为P = 0.0004、P = 0.0001和P = 0.001）。赛马的小梁厚度和骨量分数随年龄增长而增加，小梁间距减小。除掌侧外侧矢状旁沟保留更“不成熟”的模式外，在所有感兴趣区域，小梁的主要方向在新生马驹中具有一致的模式，并随成熟度和比赛的累积影响而变化。
样本采用二维方式进行研究。三维处理可能会提供更多信息。
在出生时，马驹侧矢状旁沟和髁的软骨下骨小梁微结构就存在显著差异。赛马的小梁结构随成熟度而变化，在骨量参数方面的适应性变化最为明显。成年赛马掌侧外侧矢状旁沟的小梁方向具有独特且更不成熟的方向模式，可能反映出该部位结构较弱。
