The ultrasonographic appearance of the lumbosacral symphysis of horses with no history of hindlimb lameness or thoracolumbosacral pain has previously been documented. The aims of the study were to describe the signalment and clinical findings in horses with ultrasonographic lesions of the fifth and sixth lumbar (L) vertebrae and lumbosacral symphyses and to determine whether lesions of the L5‐6 symphysis are only seen in horses with congenital sacralisation or other abnormalities of the lumbosacral symphysis. Horses in Group 1 (n = 25) underwent poor performance investigation and improved in ridden performance after infiltration of mepivacaine around the sacroiliac joints. Horses in Group 2 (n = 39) presented for investigation of changes in thoracolumbosacral shape or poor performance but did not undergo anaesthesia of the sacroiliac joint regions. The median ages were 10 and 19 years respectively for Groups 1 and 2. Mares (53.1%) were over‐represented relative to the normal populations of the clinics. All horses had poor development of the thoracolumbar epaxial and pelvic muscles and prominence of the lumbar spinous processes and the tubera sacrale. Most horses (70%) had reduced range of movement of the thoracolumbosacral region. Ultrasonographic features included irregular vertebral end plates; heterogeneous echogenicity of the intervertebral disc ± ventral protrusion; and displacement of the ventral longitudinal ligament ± alteration in its echogenicity. In Group 1, abnormalities of the L5‐6 symphysis were seen in 13 horses, of which 84.6% had congenital sacralisation or narrowing of the lumbosacral symphysis. In Group 2, the majority of horses had lesions of both the L5‐6 and lumbosacral symphyses; only 9/39 horses (23.1%) had congenital fusion of either joint. Limitations include the lack of age‐matched control horses. However, the purpose of the study was to raise awareness of lesions of the L5‐6 and lumbosacral symphyses, which may contribute to pain and poor performance.

中文翻译：

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腰s‐sa关节区域疼痛的64匹马的腰ac部或腰部5–6突触相关的超声特征（2012–2018）

以前没有记录过马的腰ac联合症的超声图谱，没有后肢la行或胸腰bo部疼痛的病史。这项研究的目的是描述患有第五和第六个腰椎（L）和腰sym共生的超声检查病变的马的信号和临床发现，并确定是否仅在先天性isation割的马中看到了L5-6共physi的病变或腰s联合症的其他异常。第1组（n = 25）中的马进行了较差的性能调查，并在me关节周围渗入了甲哌卡因后，其骑行性能得到改善。第2组（n = 39）的马表现为研究胸腰s形状或性能不佳的变化，但未对the关节区域进行麻醉。第一组和第二组的中位年龄分别为10岁和19岁。相对于诊所的正常人群，母马（53.1％）的比例过高。所有马匹的胸腰椎和骨盆肌肉发育不良，腰椎棘突和结节sa骨突出。大多数马（70％）的胸腰bo骨区域活动范围缩小。超声检查特征包括不规则的椎骨终板；椎间盘的异质回声±腹侧突出；腹纵韧带的位移和移位±回声的改变。在第1组中，在13匹马中观察到L5-6联合体异常，其中84.6％患有先天性s骨化或腰s联合体狭窄。在第2组中 大部分马同时患有L5-6和腰sym共患病；只有9/39匹马（23.1％）的任一关节先天性融合。局限性包括缺乏年龄匹配的对照马。但是，该研究的目的是提高人们对L5-6和腰s共生病变的认识，这可能会导致疼痛和不良表现。