Simmer Filho Jair, Voss Andreas, Pauzenberger Leo, Dwyer Corey R, Obopilwe Elifho, Cote Mark P, Mazzocca Augustus D, Dyrna Felix
Department of Orthopaedic Surgery, Hospital Estadual de Urgência e Emergência (HEUE), Vitória, Espírito Santo, Brasil.
Department of Trauma Surgery, University Hospital Regensburg, Regensburg, Germany.
BMC Musculoskelet Disord. 2019 Mar 25;20(1):123. doi: 10.1186/s12891-019-2479-2.
The objective of this biomechanical study is to compare two variations of single-row knotless techniques (Knotless repair and Rip-stop Knotless repair) against a single-row double-loaded anchor (DL) repair, focused on evaluating contact pressure and contact area amongst three different single-row techniques for rotator cuff repairs.
A total of 24 fresh frozen human shoulders were tested. Specimens were randomly assigned into one of the three single-row (SR) repair groups: A Knotted single-row double-loaded anchor (DL) repair, a Knotless (K) repair, or a Knotless Rip-Stop (KRS) repair. The footprint was measured after complete detachment of the supraspinatus tendon from the greater tuberosity, introducing pressure sensors between bony footprint and detached rotator cuff, and finally reconstructing it. All specimens were mounted onto a servohydraulic test system to analyze contact variables at 0° and 30° of abduction with 0 N, 30 N and 50 N of tension.
Groups did not differ significantly in their footprint sizes: DL group 359.75 ± 58.37 mm, K group 386.5 ± 102.13 mm, KRS group 415.87 ± 93.80 mm (p = 0.84); nor in bone mineral density: DL group 0.25 ± 0.14 g/cm, K group 0.32 ± 0.19 g/cm, KRS group 0.32 ± 0.13 g/cm, (p = 0.75) or average age. The highest mean pressurized contact area measured for the K repair was 248.1 ± 50.9 mm, which equals a reconstruction of 67.1 ± 19.3% at 0° abduction and a 50 N supraspinatus load. This reconstructed area was significantly greater compared with the DL repair 152.8 ± 73.1 mm, reconstructing 42.0 ± 18.5% on average when under the same conditions (p = 0.04). The mean contact pressure did not significantly differ amongst groups (p = 1.0): DL group 30.8 ± 17.4 psi, K group 30.9 ± 17.4 psi and KRS group 30.0 ± 10.9 psi. Neither the 30° abduction angle nor the supraspinatus load had a significant influence on the contact pressure in our study.
Both single-row knotless techniques resulted in significantly higher footprint reconstruction, providing larger contact area and a more uniform pressure distribution when compared with the single-row Knotted techniques. The mean contact pressure did not differ among groups significantly. These knotless techniques may be an alternative if the surgeon decides to perform a single-row rotator cuff repair.
Basic Science Study, Biomechanics.
本生物力学研究的目的是比较单排无结技术的两种变体（无结修复和防撕裂无结修复）与单排双负荷锚钉（DL）修复，重点评估三种不同单排技术用于肩袖修复时的接触压力和接触面积。
共测试24个新鲜冷冻的人体肩部标本。标本被随机分配到三个单排（SR）修复组之一：带结单排双负荷锚钉（DL）修复组、无结（K）修复组或无结防撕裂（KRS）修复组。在冈上肌腱从大结节完全分离后测量足迹，在骨足迹和分离的肩袖之间插入压力传感器，最后进行重建。所有标本安装在伺服液压测试系统上，以分析在0°和30°外展、0 N、30 N和50 N张力下的接触变量。
各组的足迹大小无显著差异：DL组为359.75±58.37平方毫米，K组为386.5±102.13平方毫米，KRS组为415.87±93.80平方毫米（p = 0.84）；骨矿物质密度也无显著差异：DL组为0.25±0.14克/立方厘米，K组为0.32±0.19克/立方厘米，KRS组为0.32±0.13克/立方厘米（p = 0.75），平均年龄也无显著差异。K修复组测得的最高平均加压接触面积为248.1±50.9平方毫米，相当于在0°外展和50 N冈上肌负荷下重建了67.1±19.3%。与DL修复组在相同条件下平均重建42.0±18.5%的152.8±73.1平方毫米相比，该重建面积显著更大（p = 0.04）。各组之间的平均接触压力无显著差异（p = 1.0）：DL组为30.8±17.4磅力/平方英寸，K组为30.9±17.4磅力/平方英寸，KRS组为30.0±10.9磅力/平方英寸。在我们的研究中，30°外展角度和冈上肌负荷对接触压力均无显著影响。
与单排带结技术相比，两种单排无结技术均能显著提高足迹重建效果，提供更大的接触面积和更均匀的压力分布。各组之间的平均接触压力无显著差异。如果外科医生决定进行单排肩袖修复，这些无结技术可能是一种替代方法。
基础科学研究，生物力学。
