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Am J Sports Med. 2012 Aug;40(8):1895-8. doi: 10.1177/0363546512448320. Epub 2012 Jun 7.
Fractures of the proximal fifth metatarsal are one of the most common forefoot injuries encountered by orthopaedic surgeons in sports medicine. The percutaneous surgical approach to Jones fracture fixation and corresponding anatomy has received little attention in the literature to date.
To describe in detail the location of the lateral dorsal cutaneous nerve (LDCN) and its branches relative to the base of the fifth metatarsal and to the standard lateral approach.
Descriptive laboratory study.
Ten fresh-frozen cadaveric foot specimens were used for this study. Specimens were dissected at the lateral aspect of the foot over the proximal fifth metatarsal, and the LDCN and its branches were identified. The distance of the LDCN to the superior border of the peroneus brevis tendon (PBT) was measured relative to standard reference points in all specimens, and the presence of an anastomotic branch was noted. A set of vertical and horizontal reference lines were also constructed to determine whether the LDCN or its branches would be compromised by a standard lateral approach.
The LDCN was superficial (ie, lateral) and inferior to the superior border of the PBT in all specimens and at all reference points. A bifurcation of the LDCN was present in 8 specimens, located an average of 18 mm posterior and 11 mm dorsal to the base of the fifth metatarsal. The dorsolateral branch and dorsomedial branch of the LDCN each intersected with the base of the fifth metatarsal horizontal line and vertical line, respectively, indicating potential compromise of the nerve with a standard lateral surgical approach.
The standard lateral approach to the base of the fifth metatarsal carries a higher risk for surgical injury to the LDCN. A "high and inside" approach that remains superior to the superior border of the PBT is anatomically safe and may decrease the chance of intraoperative nerve injury and irritation postoperatively.
足部第五跖骨近端骨折是运动医学骨科医生最常遇到的前足损伤之一。经皮手术入路治疗琼斯骨折固定及相应的解剖结构在目前的文献中还没有得到太多关注。
详细描述外侧背侧皮神经（LDCN）及其分支相对于第五跖骨基底和标准外侧入路的位置。
描述性实验室研究。
本研究使用了 10 个新鲜冷冻的足标本。在足部的外侧解剖标本，在第五跖骨近端，识别 LDCN 及其分支。在所有标本中，测量 LDCN 到腓骨短肌腱（PBT）上缘的距离，并记录吻合支的存在。还构建了一组垂直和水平参考线，以确定 LDCN 或其分支是否会因标准外侧入路而受损。
在所有标本和所有参考点上，LDCN 都位于 PBT 上缘的浅层（即外侧）和下方。8 个标本中存在 LDCN 的分支，位于第五跖骨基底后 18mm 和背侧 11mm 处。LDCN 的背外侧支和背内侧支分别与第五跖骨的横线和竖线相交，表明标准外侧手术入路可能会损伤神经。
第五跖骨基底的标准外侧入路存在更高的 LDCN 手术损伤风险。一种保持在 PBT 上缘以上的“高而内”入路在解剖上是安全的，可能会降低术中神经损伤和术后神经刺激的几率。
