Stanford University Medical Center, Stanford, CA, USA.
Foot Ankle Int. 2010 Feb;31(2):164-71. doi: 10.3113/FAI.2010.0164.
Tibiocalcaneal arthrodesis is an uncommon salvage procedure used for complex problems of the ankle and hindfoot. A biomechanical evaluation of the fixation constructs of this procedure has not been studied previously. The purpose of this study was to compare intramedullary nail to blade plate fixation in a deformity model in fatigue endurance testing and load to failure.
Nine matched pairs of fresh frozen cadaveric legs underwent talectomy followed by fixation with a blade plate and 6.5-mm fully threaded cancellous screw or an ankle arthrodesis intramedullary nail. The specimens were loaded to 270 N at a rate of 3 Hz for a total of 250,000 cycles, followed by loading to failure.
Intramedullary nail fixation demonstrated greater mean stiffness throughout the fatigue endurance testing, from cycles 10 through 250,000 (blade plate versus intramedullary nail; cycle 10, 93 +/- 34 N/mm versus 117 +/- 40 N/mm (t = 2.33, p = 0.04); cycle 100, 89 +/- 34 N/mm versus 118 +/- 42 N/mm (t = 3.16, p = 0.01); cycle 1000, 86 +/- 32 N/mm versus 120 +/- 45 N/mm (t = 3.52, p = 0.01); cycle 10,000, 83 +/- 36 N/mm versus 128 +/- 50 N/mm (t = 3.80, p = 0.01); cycle 100,000, 82 +/- 34 N/mm versus 126 +/- 52 N/mm (t = 3.70, p = 0.01); cycle 250,000, 80 +/- 31 N/mm versus 125 +/- 49 N/mm (t = 4.2, p = 0.003). There was no statistically significant difference between the intramedullary nail and blade plate fixation in cycle one or in load to failure; cycle 10, blade plate 70 +/- 38 N/mm and intramedullary nail 67 +/- 20 N/mm (t = 0.60, p = 0.56); load to failure, blade plate 808 +/- 193 N, IMN 1074 +/- 290 N) (p = 0.15).
Intramedullary nail fixation was biomechanically superior to blade plate and screw fixation in a tibiocalcaneal arthrodesis construct.
The ankle arthrodesis intramedullary nail provides greater stiffness for fixation in tibiocalcaneal arthrodesis, which may improve healing.
距下关节融合术是一种用于治疗踝关节和后足复杂问题的罕见挽救性手术。目前尚未对该手术固定结构的生物力学评估进行研究。本研究的目的是在疲劳耐力测试和失效负载中比较髓内钉与刀片板固定的差异。
9 对匹配的新鲜冷冻尸体下肢进行距骨切除术，然后分别采用刀片板和 6.5 毫米全螺纹松质骨螺钉或踝关节融合术髓内钉固定。标本以 3Hz 的速率加载至 270N，共进行 25 万次循环，然后进行失效负载。
髓内钉固定在整个疲劳耐力测试中表现出更高的平均刚度，从第 10 次循环到第 25 万次循环（刀片板与髓内钉相比；第 10 次循环，93 ± 34N/mm 比 117 ± 40N/mm（t = 2.33，p = 0.04）；第 100 次循环，89 ± 34N/mm 比 118 ± 42N/mm（t = 3.16，p = 0.01）；第 1000 次循环，86 ± 32N/mm 比 120 ± 45N/mm（t = 3.52，p = 0.01）；第 10000 次循环，83 ± 36N/mm 比 128 ± 50N/mm（t = 3.80，p = 0.01）；第 100000 次循环，82 ± 34N/mm 比 126 ± 52N/mm（t = 3.70，p = 0.01）；第 250000 次循环，80 ± 31N/mm 比 125 ± 49N/mm（t = 4.2，p = 0.003）。髓内钉和刀片板固定在第 1 次循环或失效负载中均无统计学差异；第 10 次循环，刀片板 70 ± 38N/mm，髓内钉 67 ± 20N/mm（t = 0.60，p = 0.56）；失效负载，刀片板 808 ± 193N，IMN 1074 ± 290N）（p = 0.15）。
在距下关节融合术构建中，髓内钉固定在生物力学上优于刀片板和螺钉固定。
踝关节融合术髓内钉为距下关节融合术提供了更强的固定刚度，这可能有助于愈合。
