Karaarslan A A, Acar N
Orthopedics and Traumatology Department, Batı Anadolu Central Hospital, 6225 Sok. No: 93/A, 35100, Bayraklı, Izmir, Turkey.
Department of Orthopaedics and Traumatology, Catalca Ilyas Cokay Hospital, 34540, Catalca, Istanbul, Turkey.
Eur J Trauma Emerg Surg. 2018 Feb;44(1):97-103. doi: 10.1007/s00068-017-0823-5. Epub 2017 Jul 27.
Rotation instability and locking screws failure are common problems. We aimed to determine optimal torque wrench offering maximum rotational stiffness without locking screw failure.
We used 10 conventional compression nails, 10 novel compression nails and 10 interlocking nails with 30 composite femurs. We examined rotation stiffness and fracture site compression value by load cell with 3, 6 and 8 Nm torque wrenches using torsion apparatus with a maximum torque moment of 5 Nm in both directions. Rotational stiffness of composite femur-nail constructs was calculated.
Rotational stiffness of composite femur-compression nail constructs compressed by 6 Nm torque wrench was 3.27 ± 1.81 Nm/angle (fracture site compression: 1588 N) and 60% more than that compressed with 3 Nm torque wrench (advised previously) with 2.04 ± 0.81 Nm/angle (inter fragmentary compression: 818 N) (P = 0.000). Rotational stiffness of composite-femur-compression nail constructs compressed by 3 Nm torque wrench was 2.04 ± 0.81 Nm/angle (fracture site compression: 818 N) and 277% more than that of interlocking nail with 0.54 ± 0.08 Nm/angle (fracture site compression: 0 N) (P = 0.000).
Rotational stiffness and fracture site compression value produced by 3 Nm torque wrench was not satisfactory. To obtain maximum rotational stiffness and fracture site compression value without locking screw failure, 6 Nm torque wrench in compression nails and 8 Nm torque wrench in novel compression nails should be used.
旋转不稳定和锁定螺钉失效是常见问题。我们旨在确定能提供最大旋转刚度且不会导致锁定螺钉失效的最佳扭矩扳手。
我们使用10枚传统加压钉、10枚新型加压钉和10枚带锁髓内钉，以及30根复合股骨。我们使用最大扭矩为5 Nm的扭转装置，通过测力传感器，用3 Nm、6 Nm和8 Nm的扭矩扳手检查旋转刚度和骨折部位的压缩值。计算复合股骨-钉结构的旋转刚度。
用6 Nm扭矩扳手压缩的复合股骨-加压钉结构的旋转刚度为3.27±1.81 Nm/角度（骨折部位压缩：1588 N），比之前建议的用3 Nm扭矩扳手压缩时的旋转刚度（2.04±0.81 Nm/角度，骨折部位压缩：818 N）高60%（P = 0.000）。用3 Nm扭矩扳手压缩的复合股骨-加压钉结构的旋转刚度为2.04±0.81 Nm/角度（骨折部位压缩：818 N），比带锁髓内钉的旋转刚度（0.54±0.08 Nm/角度，骨折部位压缩：0 N）高277%（P = 0.000）。
3 Nm扭矩扳手产生的旋转刚度和骨折部位压缩值并不理想。为了在不发生锁定螺钉失效的情况下获得最大旋转刚度和骨折部位压缩值，加压钉应使用6 Nm扭矩扳手，新型加压钉应使用8 Nm扭矩扳手。
