Smíd P, Hart R, Puskeiler M
Ortopedicko-traumatologické oddělení Nemocnice Znojmo.
Acta Chir Orthop Traumatol Cech. 2014;81(3):227-32.
Repair techniques for rotator cuff injury are currently well advanced. However, the risk of re-rupture, particularly when severe damage to the tendons has been repaired, is still high. The causes of failure can be due to the extent of injury, a repair done on a highly degenerated tendon with diminished viability or ischaemic damage to the tendon tissue resulting from suture material. The aim of the study was to ascertain the reliability of the tangent sign, a commonly used indicator of the degree of suprasupinatus muscle atrophy, in the prediction of risk for tendon re-rupture in the post-operative period.
In 2011 the rotator cuff torn tendons were repaired by the method of double-row suture in 37 patients. The surgery was done by an open technique using the deltoid-splitting approach. A pre-operative magnetic resonance image (MRI) of the shoulder was obtained in all patients and each was assessed by a competent independent radiology specialist with a focus on the extent of a tendon lesion and the tangent sign. At 2-year follow-up, the results of repeated MRI were evaluated in view of the state of repaired tendons and, if a re-tear was found, its relation to the original suture and its extent in the sagittal plane were determined. The pre- and post-operative MRI findings were compared to find out how the presence or absence of a tangent sign before surgery relates to the incidence of supraspinatus tendon re-rupture at 2 years after surgery. The results were statistically analysed using Student's t-test and the Chi-square test.
Of the 37 shoulders, in the pre-operative period, a tangent sign was identified in 21 (56.8%). The average size of a rotator cuff tear was 29.3 mm for the whole group. For the shoulders with no tangent sign, the average value was 21.8 mm, for those with a tangent sign present, it was 39.6 mm. At 2-year follow-up, no tear was found in the patients in whom preoperative MRI showed no tangent sign while re-tears were recorded in 18 of 21 shoulders (85.7%) with a tangent sign present before surgery. On the average, the re-rupture had 40.8 mm in size and, in all cases, it occurred at the site of tendon re-insertion into the greater tubercle. These results were statistically significant (p < 0.01).
In repair of injury to the tendons of the rotator cuff muscles, emphasis is currently placed on a thorough pre-operative examination. MRI is an important part of the diagnostic procedure because it provides a detailed image of the muscle as a whole. Although great advances have recently been made in both the diagnostic and surgical techniques, the incidence of tendon re-rupture within a few years of the procedure is still high.
Our results show that the presence of a tangent sign detected by pre-operative MRI examination of the shoulder can be an important predictor of failure in rotator cuff repair and can also turn attention to the selection of an alternative technique to be used.
目前肩袖损伤的修复技术已相当先进。然而，再次断裂的风险仍然很高，尤其是在修复严重受损肌腱时。失败的原因可能是损伤程度、对高度退变且活力降低的肌腱进行修复，或是缝合材料导致肌腱组织的缺血性损伤。本研究的目的是确定切线征（一种常用的冈上肌萎缩程度指标）在预测术后肌腱再次断裂风险方面的可靠性。
2011年，采用双排缝合方法对37例患者的肩袖撕裂肌腱进行修复。手术采用开放技术，经三角肌劈开入路。所有患者均获得肩部术前磁共振成像（MRI），并由一名合格的独立放射科专家进行评估，重点关注肌腱损伤程度和切线征。在2年随访时，根据修复肌腱的状态评估重复MRI的结果，如果发现再次撕裂，确定其与原始缝合的关系及其在矢状面的范围。比较术前和术后MRI结果，以了解术前切线征的有无与术后2年冈上肌腱再次断裂发生率之间的关系。结果采用Student's t检验和卡方检验进行统计学分析。
在37例肩部中，术前有21例（56.8%）出现切线征。全组肩袖撕裂的平均大小为29.3mm。对于无切线征的肩部，平均值为21.8mm，对于有切线征的肩部，平均值为39.6mm。在2年随访时，术前MRI显示无切线征的患者未发现撕裂，而术前有切线征且存在的21例肩部中有18例（85.7%）记录到再次撕裂。再次断裂的平均大小为40.8mm，且在所有病例中均发生在肌腱重新附着于大结节的部位。这些结果具有统计学意义（p < 0.01）。
在肩袖肌肌腱损伤的修复中，目前强调进行全面的术前检查。MRI是诊断程序的重要组成部分，因为它能提供肌肉整体的详细图像。尽管近年来诊断和手术技术都取得了很大进展，但术后几年内肌腱再次断裂的发生率仍然很高。
我们的结果表明，肩部术前MRI检查发现的切线征的存在可能是肩袖修复失败的重要预测指标，也可促使关注替代技术的选择。
