Iannuzzi Nicholas P, Paez Adrian G, Parks Brent G, Murphy Michael S
The Curtis National Hand Center, MedStar Union Memorial Hospital, Baltimore, MD.
The Curtis National Hand Center, MedStar Union Memorial Hospital, Baltimore, MD.
J Hand Surg Am. 2017 Jan;42(1):e11-e14. doi: 10.1016/j.jhsa.2016.11.003.
The aim of this study was to compare the load to failure and stiffness achieved in coronoid fractures treated with a posterior-to-anterior screw versus a suture lasso technique.
We performed a biomechanical study using 10 pairs of fresh-frozen cadaveric elbows. A transverse osteotomy at the midpoint of the coronoid height was created to simulate a Regan-Morrey type II coronoid fracture. The specimens were randomized to screw fixation or suture lasso fixation. The load to failure and stiffness were then measured using a materials testing machine.
Screw fixation provided greater strength and stiffness than suture lasso fixation. Mean load to failure was 405 N in the screw fixation group compared with a load to failure of 207 N for suture fixation. Screw fixation resulted in a mean stiffness of 284 kPa/mm compared with 119 kPa/mm after suture fixation.
Screw fixation was biomechanically superior to fixation using a suture lasso technique. For coronoid fractures in which screw or suture fixation is feasible, screw fixation may provide greater resistance to displacement of the coronoid compared with a suture lasso technique.
Clinical studies have reported a higher rate of failure after screw fixation compared with suture lasso fixation; however, this study demonstrated a greater stiffness and load to failure after screw fixation of type II coronoid fractures. Screw fixation may provide a stronger fixation construct for fractures of adequate size to support a screw. Further studies may be warranted to assess the importance of securing the anterior capsule to the coronoid tip when using a suture lasso construct because this may affect the stability of the elbow after fixation.
本研究旨在比较采用前后向螺钉与缝线套索技术治疗的冠突骨折的失效负荷和刚度。
我们使用10对新鲜冷冻尸体肘部进行了一项生物力学研究。在冠突高度中点处进行横向截骨，以模拟Regan-Morrey II型冠突骨折。将标本随机分为螺钉固定组或缝线套索固定组。然后使用材料试验机测量失效负荷和刚度。
螺钉固定比缝线套索固定提供了更大的强度和刚度。螺钉固定组的平均失效负荷为405 N，而缝线固定组的失效负荷为207 N。螺钉固定的平均刚度为284 kPa/mm，而缝线固定后为119 kPa/mm。
螺钉固定在生物力学上优于缝线套索技术固定。对于可行螺钉或缝线固定的冠突骨折，与缝线套索技术相比，螺钉固定可能对冠突移位具有更大的抵抗力。
临床研究报告称，与缝线套索固定相比，螺钉固定后的失败率更高；然而，本研究表明，II型冠突骨折螺钉固定后的刚度和失效负荷更大。对于有足够尺寸以支撑螺钉的骨折，螺钉固定可能提供更强的固定结构。当使用缝线套索结构时，可能需要进一步研究以评估将前侧关节囊固定到冠突尖端的重要性，因为这可能会影响固定后肘部的稳定性。
