The Taylor Collaboration, San Francisco, California, USA.
Medical Device Development, San Francisco, California, USA.
Am J Sports Med. 2019 Mar;47(4):928-932. doi: 10.1177/0363546518820304. Epub 2019 Jan 28.
Throwing athletes with ulnar collateral ligament (UCL) injury and symptomatic valgus instability can expect to return to the same or higher level of play. Reconstruction with tendon graft is the dominant method of surgical treatment. Recent evidence suggests that spanning the joint with a suture anchored on both sides is biomechanically equivalent to reconstruction, with faster time to return to play. The authors developed a hybrid UCL reconstruction technique augmented with a suture brace to improve joint stability.
PURPOSE/HYPOTHESIS: The purpose of this study was to biomechanically evaluate a hybrid reconstruction technique and compare its performance to reconstruction without augmentation. The authors hypothesized that (1) both groups would lose stability after the simulated tear and regain stability with treatment, (2) the suture augmentation would improve stability, and (3) the addition of the suture anchors near the bone tunnels would not decrease the strength of the hybrid reconstruction.
Controlled laboratory study.
Ten matched pairs of cadaveric arms were dissected to expose the UCL. Each elbow was mounted on a test frame at 90° of flexion. A cyclic valgus rotational torque was applied to the humerus with the UCL in its intact state and repeated in its surgically torn state. Finally, each specimen received either a hybrid reconstruction with suture brace or a reconstruction and was again put through the cyclic protocol, followed by a valgus rotation load-to-fail protocol.
Gap formation in the torn state for the reconstruction and hybrid reconstruction groups (0.9 ± 0.1 mm and 0.8 ± 0.1 mm, respectively) was significantly higher ( P = .009 and P = .0002) than in the intact state (0.6 ± 0.2 mm and 0.6 ± 0.3 mm, respectively). After the procedures, the hybrid group showed greater resistance to gapping ( P = .017) as compared with the reconstruction group (0.4 ± 0.2 mm and 0.6 ± 0.1 mm). During load to failure, no hybrid reconstructions failed from bone fracture or screw pullout. No statistical differences were found for failure torque ( P = .058) and stiffness ( P = .101). Gap at 10 N·m was significantly lower ( P = .014) for the hybrid reconstruction group than for the reconstruction group.
The current study showed that hybrid reconstruction with suture bracing replicated the time-zero strength of traditional UCL reconstruction and may be more resistant to joint gapping during low cyclic load and load to failure. The combination of the bone tunnels and fixation screw holes did not appear to weaken the construct.
This study demonstrated that reconstruction with suture bracing has important time-zero stability and strength as compared with the gold standard of UCL reconstruction. This technique may be useful for throwing athletes who need UCL reconstruction.
患有 UCL 损伤和有症状的外翻不稳定的投掷运动员有望恢复到相同或更高的运动水平。使用肌腱移植物重建是手术治疗的主要方法。最近的证据表明，用两侧固定的缝线跨越关节在生物力学上等同于重建，并且恢复运动的时间更快。作者开发了一种混合 UCL 重建技术，并用缝线支撑物进行增强，以提高关节稳定性。
目的/假设：本研究的目的是对混合重建技术进行生物力学评估，并将其性能与无增强重建进行比较。作者假设：(1)两组在模拟撕裂后都会失去稳定性，但经过治疗后会恢复稳定性；(2)缝线增强会提高稳定性；(3)在骨隧道附近添加缝线锚定不会降低混合重建的强度。
对照实验室研究。
对 10 对匹配的尸体手臂进行解剖以暴露 UCL。每个肘部都在 90°弯曲的测试框架上进行安装。在 UCL 处于完整状态和手术撕裂状态下，对肱骨施加周期性外翻旋转扭矩。最后，每个标本都接受了混合重建加缝线支撑或重建，并再次通过循环协议进行处理，然后进行外翻旋转失效负载协议。
撕裂状态下重建组和混合重建组的间隙形成（分别为 0.9 ± 0.1 mm 和 0.8 ± 0.1 mm）明显高于完整状态下的间隙形成（分别为 0.6 ± 0.2 mm 和 0.6 ± 0.3 mm）（P =.009 和 P =.0002）。在手术后，混合组比重建组更能抵抗间隙形成（P =.017）（分别为 0.4 ± 0.2 mm 和 0.6 ± 0.1 mm）。在失效负载下，没有混合重建因骨骨折或螺钉拔出而失效。失效扭矩（P =.058）和刚度（P =.101）没有统计学差异。混合重建组的 10 N·m 时的间隙明显低于重建组（P =.014）。
目前的研究表明，带缝线支撑的混合重建复制了传统 UCL 重建的初始强度，并且在低循环负载和失效负载下可能更能抵抗关节间隙。骨隧道和固定螺钉孔的组合似乎没有削弱构建体。
本研究表明，与 UCL 重建的金标准相比，带缝线支撑的重建具有重要的初始稳定性和强度。这种技术可能对需要 UCL 重建的投掷运动员有用。
