Owen K R, Dyson S J, Parkin T D H, Singer E R, Kristoffersen M, Mair T S
Centre for Equine Studies, Animal Health Trust, Newmarket, Suffolk, UK.
Equine Vet J. 2008 May;40(3):237-44. doi: 10.2746/042516408X271217.
Constriction of the digital flexor tendon sheath (DFTS) and its contents by the palmar/plantar annular ligament (PAL) is well recognised. However, primary injury of the PAL has not been well documented.
To describe the clinical features of PAL injury, determine its prevalence with or without subcutaneous fibrosis and/or concurrent injury within the DFTS, and assess response to treatment.
Horses were selected for inclusion based upon clinical features consistent with PAL injury and the presence of a thickened PAL (> or =2 mm) verified ultrasonographically. A retrospective analysis of case records from 3 clinics was performed. Details of breed, age and use, and results of clinical and ultrasonographic assessments and response to treatment were recorded. Horses were treated conservatively or surgically by desmotomy of the PAL, with or without tenoscopic evaluation of the DFTS. A telephone questionnaire was performed to assess response to treatment.
Seventy-one horses were included in the study and middle aged or older general purpose riding horses predominated. PAL desmopathy occurred more frequently in hind- than in forelimbs. The method of treatment, thickness of the PAL or presence of subcutaneous fibrosis did not significantly affect prognosis; however, <50% of horses were able to return to athletic function. There was a trend for horses with PAL desmopathy alone to have the best outcome. Bilateral thickening of the PAL or concurrent fore- and hindlimb injuries had a negative effect on prognosis, as did the simultaneous presence of subcutaneous fibrosis and lesions within the DFTS.
PAL injury is characterised by a convex contour of the palmar/plantar aspect of the fetlock, associated with thickening of the ligament with or without subcutaneous fibrosis. Bilateral PAL thickening is common in older horses, ponies and cobs; however, bilateral PAL enlargement is often present with only unilateral lameness. Treatment methods used in this study did not appear to influence outcome significantly.
掌/跖环形韧带（PAL）对指屈肌腱鞘（DFTS）及其内容物的约束作用已得到充分认识。然而，PAL的原发性损伤尚未得到充分记录。
描述PAL损伤的临床特征，确定其在伴有或不伴有皮下纤维化和/或DFTS内并发损伤时的发生率，并评估治疗反应。
根据与PAL损伤一致的临床特征以及超声检查证实的PAL增厚（≥2mm）来选择纳入研究的马匹。对来自3家诊所的病例记录进行回顾性分析。记录品种、年龄、用途的详细信息，以及临床和超声评估结果及治疗反应。对马匹进行保守治疗或通过PAL离断术进行手术治疗，同时对DFTS进行或不进行关节镜评估。通过电话问卷调查来评估治疗反应。
71匹马被纳入研究，其中以中老年通用骑乘马为主。PAL病变在马匹后肢比前肢更常见。治疗方法、PAL厚度或皮下纤维化的存在对预后没有显著影响；然而，不到50%的马匹能够恢复运动功能。仅患有PAL病变的马匹预后最好。PAL双侧增厚或前肢和后肢同时受伤对预后有负面影响，DFTS内同时存在皮下纤维化和病变也是如此。
PAL损伤的特征是跗关节掌/跖侧呈凸形轮廓，伴有韧带增厚，伴有或不伴有皮下纤维化。PAL双侧增厚在老年马、矮种马和科布马中很常见；然而，PAL双侧增大通常仅伴有单侧跛行。本研究中使用的治疗方法似乎对结果没有显著影响。
