Dayton Paul, Feilmeier Mindi, Kauwe Merrell, Holmes Colby, McArdle Austin, Coleman Nathan
Foot and Ankle Division, UnityPoint Clinic, and Adjunct Professor, Des Moines University College of Podiatric Medicine and Surgery, Fort Dodge, IA.
Assistant Professor, Des Moines University College of Podiatric Medicine and Surgery, Fort Dodge, IA.
J Foot Ankle Surg. 2014 Sep-Oct;53(5):584-7. doi: 10.1053/j.jfas.2014.02.003. Epub 2014 Mar 18.
It is well known that the pathologic positions of the hallux and the first metatarsal in a bunion deformity are multiplanar. It is not universally understood whether the pathologic changes in the hallux or first metatarsal drive the deformity. We have observed that frontal plane rotation of the hallux can result in concurrent positional changes proximally in the first metatarsal in hallux abducto valgus. In the present study, we observed the changes in common radiographic measurements used to evaluate a bunion deformity in 5 fresh frozen cadaveric limbs. We measured the tibial sesamoid position, 1-2 intermetatarsal angle, and first metatarsal cuneiform angle on anteroposterior radiographs after frontal and transverse plane manipulation of the hallux. When the hallux was moved into an abducted and valgus position, a statistically significant increase was found in the tibial sesamoid position (p = .016). However, we did not observe a significant increase in the intermetatarsal angle (p = .070) or medial cuneiform angle (p = .309). When the hallux was manipulated into an adducted and varus position, a statistically significant decrease in the intermetatarsal angle (p = .02) and a decrease in the tibial sesamoid position (p = .016) was seen, with no significant change in the medial cuneiform angle (p = .360). We also observed a consistent rounding of the lateral aspect of the first metatarsal head and an increase in the concavity of the lateral metatarsal shaft, with valgus rotation of the hallux. From these observations, it is possible that the hallux could drive the proximal changes in the first ray that lead to metatarsus primus adducto valgus deformity.
众所周知，拇外翻畸形中拇趾和第一跖骨的病理位置是多平面的。拇趾或第一跖骨的病理变化是否导致畸形，目前尚未得到普遍理解。我们观察到，拇趾在额状面的旋转可导致拇外翻时第一跖骨近端同时发生位置变化。在本研究中，我们观察了5个新鲜冷冻尸体下肢中用于评估拇外翻畸形的常见影像学测量值的变化。在对拇趾进行额状面和横断面操作后，我们在前后位X线片上测量了胫侧籽骨位置、第一、二跖骨间角和第一跖骨与楔骨间角。当拇趾移至外展和外翻位置时，胫侧籽骨位置有统计学意义的增加（p = 0.016）。然而，我们未观察到跖骨间角（p = 0.070）或内侧楔骨角（p = 0.309）有显著增加。当拇趾被操作至内收和内翻位置时，跖骨间角有统计学意义的减小（p = 0.02），胫侧籽骨位置减小（p = 0.016），而内侧楔骨角无显著变化（p = 0.360）。我们还观察到，随着拇趾外翻旋转，第一跖骨头外侧持续变圆，外侧跖骨干凹陷增加。从这些观察结果来看，拇趾有可能导致第一跖骨近端的变化，进而导致第一跖骨内收外翻畸形。
