Aydogan Umur, Moore Blake, Andrews Seth H, Roush Evan P, Kunselman Allen R, Lewis Gregory S
Penn State Hershey Bone and Joint Institute, 30 Hope Drive, Hershey, PA 17033. E-mail address for U. Aydogan:
Department of Orthopaedics and Rehabilitation (S.H.A., E.P.R., and G.S.L.) and Department of Public Health Sciences (A.R.K.), Penn State Hershey College of Medicine, 500 University Drive, Hersey, PA 17033. E-mail address for G.S. Lewis:
J Bone Joint Surg Am. 2015 Dec 2;97(23):1945-51. doi: 10.2106/JBJS.O.00216.
The optimal surgery for reducing pressure under the second metatarsal head to treat metatarsalgia is unknown. We tested our hypothesis that a proximal oblique dorsiflexion osteotomy of the second metatarsal would decrease second-metatarsal plantar pressures in a cadaver model with varying Achilles tendon tension. We also tested the plantar pressure effects of two popular techniques of distal oblique osteotomy.
Twelve fresh-frozen feet from six cadavers were randomly assigned to either the distal osteotomy group (a classic distal oblique osteotomy followed by a modified distal oblique osteotomy) or proximal metatarsal osteotomy group. Each specimen was tested intact and then after the osteotomy or osteotomies. The feet were loaded with 0, 300, and 600 N of Achilles tendon tension and a 400-N ground reaction force. Plantar pressures were measured by a pressure sensitive mat and analyzed in sections located under each metatarsal.
The proximal metatarsal osteotomy significantly reduced average pressures beneath the second metatarsal head during both 300 and 600 N of Achilles tendon loading by an average of 19.4 and 29.7 kPa, respectively (p < 0.05). The modified distal oblique osteotomy significantly decreased these pressures during 600 N of Achilles tendon loading, by a mean of 20.2 kPa, which was to a lesser extent than the proximal metatarsal osteotomy. Interestingly, the classic distal oblique osteotomy was not found to have significant effects on pressures beneath the second metatarsal head.
The proximal oblique dorsiflexion metatarsal osteotomy may be the most effective procedure for decreasing plantar pressures under the second metatarsal. The modified distal oblique osteotomy may be the second most effective.
The findings of this biomechanical study help shed light on which of the common second metatarsal osteotomies are best for decreasing plantar pressures.
减轻第二跖骨头下压力以治疗跖痛症的最佳手术方式尚不清楚。我们检验了这样一个假设：在不同跟腱张力的尸体模型中，第二跖骨近端斜行背屈截骨术会降低第二跖骨的足底压力。我们还测试了两种常用的远端斜行截骨术对足底压力的影响。
将来自6具尸体的12只新鲜冷冻足随机分为远端截骨组（经典远端斜行截骨术，随后进行改良远端斜行截骨术）或跖骨近端截骨组。每个标本先进行完整测试，然后在进行一次或多次截骨术后再次测试。足部加载0、300和600 N的跟腱张力以及400 N的地面反作用力。通过压力敏感垫测量足底压力，并在每个跖骨下方的区域进行分析。
在300 N和600 N的跟腱加载过程中，跖骨近端截骨术分别使第二跖骨头下方的平均压力显著降低，平均降低幅度分别为19.4 kPa和29.7 kPa（p < 0.05）。在600 N的跟腱加载过程中，改良远端斜行截骨术使这些压力显著降低，平均降低20.2 kPa，降低程度小于跖骨近端截骨术。有趣的是，未发现经典远端斜行截骨术对第二跖骨头下方的压力有显著影响。
第二跖骨近端斜行背屈截骨术可能是降低第二跖骨下方足底压力最有效的手术方法。改良远端斜行截骨术可能是第二有效的方法。
这项生物力学研究的结果有助于阐明哪种常见的第二跖骨截骨术最适合降低足底压力。
