Comparison of the Calcaneal Pitch Angle and Modified Projection Area Per Length Squared Method for Medial Longitudinal Arch Evaluation of the Foot

Abstract

Objective: To compare the calcaneal pitch angle (CPA) values measured on direct lateral radiographs of feet, and the modified projection area per length squared (PAL), which was calculated as a new method for the evaluation of the medial longitudinal arch (MLA) of the foot. Material and Methods: Direct lateral radiographs of patients who had weightbearing feet radiographies for any reason except trauma were retrospectively obtained from the archives. Direct lateral radiographs of the feet were printed and a transparent sheet was placed on it. A straight line was drawn between the most plantar process of the calcaneus and the head of the first metatarsal bone for the calculation of the PAL of the MLA. Two semilunar arcs were drawn upon this straight line. PAL1 and PAL2 were estimated using a point-counting technique. The CPA, lateral talo-calcaneal angles (LTCA), and talo-first metatarsal angles (TFMA) were measured. The correlations between PAL1, PAL2 of right and left feet and CPA, LTCA, and TFMA were explored. Results: Fifty patients (27 females, 23 males) with a mean age of 40.12 (4-78) years were evaluated. Significant correlations were detected between PAL1, PAL2 and CPA, and TFMA for both right and left feet (p<0.05). Conclusion: A significant correlation was detected between the modified PAL method as a new technique and the standard CPA method for MLA evaluation. The PAL method is suggested as a simple and practical method for MLA evaluation. Turkish Başlık: Ayağın Mediyal Longitudinal Arkının Değerlendirilmesinde Kalkaneal Pitch Açısı İle Modifiye Projeksiyon Alanı Metodunun Karşılaştırılması Anahtar Kelimeler: Mediyal longitudinal ark, kalkaneal pitch açısı, projeksiyon alanı Amaç: Ayağın mediyal longitudinal arkının (MLA) değerlendirilmesinde ayak direkt lateral grafisinde ölçülen kalkaneal pitch açısı (KPA) değerleri ile alternatif metod olarak modifiye projeksiyon alanı (PA) metodunun karşılaştırılması. Materyal, Metod: Travma dışında herhangi bir nedenle basarak ayak grafisi çekilmiş hastaların lateral direkt ayak grafileri arşivden tarandı. Ayak direkt lateral radyografileri basıldı ve üzerine transparan kağıt yerleştirildi. MLA'nın PA değerini hesaplamak için kalkaneusun en plantar çıkıntısı ile birinci metatarsal kemiğin başı arasına düz çizgi çizildi. Bu düz çizgi üzerinde iki semilunar ark çizildi. PA1 ve PA2 nokta sayma tekniği ile belirlendi. KPA, lateral talo kalkaneal açı (LTKA) ve talo-birinci metatarsal açı (TBMA) ölçüldü. Sağ ve sol ayak için PA1, PA2 ile KPA, LTKA ve TBMA arasındaki korelasyonlar araştırıldı. Bulgular: Yaş ortalaması 40.12 (4-78) yıl olan, elli hasta (27 kadın, 23 erkek) değerlendirildi. Hem sağ ve hem de sol ayak için PA1, PA2 ve KPA ve TBMA arasında anlamlı korelasyon olduğu saptandı (p<0,05). Sonuç: MLA'ın değerlendirilmesinde standart bir metod olan KPA ile yeni bir teknik olan modifiye PA arasında anlamlı ilişki olduğu saptandı. PA metodu, MLA değerlendirilmesinde basit ve pratik bir yöntem olarak önerilebilir.

Keywords

• Medial longitudinal arch, calcaneal pitch angle, projection area per length squared

Comparison of the Calcaneal Pitch Angle and Modified Projection Area Per Length Squared Method for Medial Longitudinal Arch Evaluation of the Foot

Öz

Kaynakça

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