Marsland Daniel, Konan Sujith, Eleftheriou Kyriacos, Calder James, Elliot Robin R
Specialist Registrar, Trauma and Orthopaedics, University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom.
Specialist Registrar, Trauma and Orthopaedics, Chelsea and Westminster Hospital National Health Service Trust, London, United Kingdom.
J Foot Ankle Surg. 2016 May-Jun;55(3):509-12. doi: 10.1053/j.jfas.2016.01.046. Epub 2016 Mar 9.
Precontoured, low-profile plates with fixed dorsiflexion angles are becoming increasingly popular for first metatarsophalangeal joint fusion. We have concerns that the routine use of a precontoured plate can lead to excessive clinical dorsiflexion. The aim of our study was to investigate the relationship between the first metatarsophalangeal joint dorsiflexion intramedullary angle and the angle formed at the dorsal cortices where the plate is applied. We hypothesized that the dorsal cortical angle was significantly less dorsiflexed than the intramedullary angle. We measured both angles on lateral weightbearing radiographs of 40 consecutive individuals presenting with forefoot symptoms. The results demonstrated that the mean dorsal cortical angle was significantly smaller (mean 0.2° plantarflexion) compared with the intramedullary angle (mean 10.6° dorsiflexion; p < .001). The interobserver and intraobserver reliability of both the intramedullary and the dorsal cortical measurements was very good. In conclusion, the dorsal cortical angle is, on average, 10.8° smaller than the intramedullary angle, with a mean angle of almost 0°. This finding should be considered when selecting plates for first metatarsophalangeal joint fusion.
带有固定背屈角度的预塑形、低轮廓钢板在第一跖趾关节融合术中越来越受欢迎。我们担心常规使用预塑形钢板会导致临床上过度的背屈。我们研究的目的是调查第一跖趾关节背屈髓内角度与钢板应用处背侧皮质形成的角度之间的关系。我们假设背侧皮质角度的背屈程度明显小于髓内角度。我们在40例连续出现前足症状的个体的负重侧位X线片上测量了这两个角度。结果表明，与髓内角度（平均背屈10.6°）相比，平均背侧皮质角度明显更小（平均跖屈0.2°；p <.001）。髓内和背侧皮质测量的观察者间和观察者内可靠性都非常好。总之，背侧皮质角度平均比髓内角度小10.8°，平均角度几乎为0°。在为第一跖趾关节融合术选择钢板时应考虑这一发现。
