Hackl Michael, Nacov Julia, Kammerlohr Sandra, Staat Manfred, Buess Eduard, Leschinger Tim, Müller Lars P, Wegmann Kilian
University of Cologne, Faculty of Medicine, Cologne, Germany.
University Hospital Cologne, Center of Orthopedic and Trauma Surgery, Cologne, Germany.
Am J Sports Med. 2021 Jun;49(7):1847-1853. doi: 10.1177/03635465211006138. Epub 2021 Apr 19.
Double-row (DR) and transosseous-equivalent (TOE) techniques for rotator cuff repair offer more stability and promote better tendon healing compared with single-row (SR) repairs and are preferred by many surgeons. However, they can lead to more disastrous retear patterns with failure at the medial anchor row or the musculotendinous junction. The biomechanics of medial cuff failure have not been thoroughly investigated thus far.
To investigate the intratendinous strain distribution within the supraspinatus tendon depending on repair technique.
Controlled laboratory study.
Twelve fresh-frozen cadaveric shoulders were used. The intratendinous strain within the supraspinatus tendon was analyzed in 2 regions-(1) at the footprint at the greater tuberosity and (2) medial to the footprint up to the musculotendinous junction-using a high-resolution 3-dimensional camera system. Testing was performed at submaximal loads of 40 N, 60 N, and 80 N for intact tendons, after SR repair, after DR repair, and after TOE repair.
The tendon strain of the SR group differed significantly in both regions from that of the intact tendons and the TOE group at 40 N (≤ .043) and from the intact tendons, the DR group, and the TOE group at 60 N and 80 N (≤ .048). SR repairs showed more tendon elongation at the footprint and less elongation medial to the footprint. DR and TOE repairs did not provide significant differences in tendon strain when compared with the intact tendons. However, the increase in tendon strain medial to the footprint from 40 N to 80 N was significantly more pronounced in the DR and TOE group (≤ .029).
While DR and TOE repair techniques more closely reproduced the strains of the supraspinatus tendon than did SR repair in a cadaveric model, they showed a significantly increased tendon strain at the musculotendinous junction with higher loads in comparison with the intact tendon.
DR and TOE rotator cuff reconstructions lead to a more anatomic tendon repair. However, their use has to be carefully evaluated whenever tendon quality is diminished, as they lead to a more drastic increase in tendon strain medial to the footprint, putting these repairs at risk of medial cuff failure.
与单排（SR）修复相比，双排（DR）和经骨等效（TOE）技术用于修复肩袖提供了更高的稳定性并能促进肌腱更好地愈合，因而受到许多外科医生的青睐。然而，它们可能导致更严重的再撕裂模式，在内侧锚钉排或肌腱肌肉交界处出现失败。迄今为止，内侧肩袖失败的生物力学尚未得到充分研究。
根据修复技术研究冈上肌腱内的腱内应变分布。
对照实验室研究。
使用12个新鲜冷冻的尸体肩部。使用高分辨率三维摄像系统分析冈上肌腱内两个区域的腱内应变——（1）在大结节处的足迹部位，（2）足迹部位内侧直至肌腱肌肉交界处。对完整肌腱、SR修复后、DR修复后和TOE修复后的标本在40 N、60 N和80 N的次最大负荷下进行测试。
在40 N时，SR组在两个区域的肌腱应变与完整肌腱和TOE组均有显著差异（≤0.043）；在60 N和80 N时，与完整肌腱、DR组和TOE组均有显著差异（≤0.048）。SR修复在足迹部位显示出更多的肌腱伸长，而在足迹部位内侧伸长较少。与完整肌腱相比，DR和TOE修复在肌腱应变方面没有显著差异。然而，在DR组和TOE组中，从40 N到80 N时足迹部位内侧的肌腱应变增加更为明显（≤0.029）。
在尸体模型中，虽然DR和TOE修复技术比SR修复更能重现冈上肌腱的应变，但与完整肌腱相比，在更高负荷下它们在肌腱肌肉交界处的肌腱应变显著增加。
DR和TOE肩袖重建可实现更符合解剖结构的肌腱修复。然而，每当肌腱质量下降时，必须仔细评估其使用情况，因为它们会导致足迹部位内侧的肌腱应变急剧增加，使这些修复面临内侧肩袖失败的风险。
