Comparison of Deformity with Respect to the Talus in Patients with Posterior Tibial Tendon Dysfunction and Controls Using Multiplanar Weight-Bearing Imaging or Conventional Radiography

SLR - August 2014 - Kendra Anderson

Reference: Haleem AM, et al. Comparison of Deformity with Respect to the Talus in Patients with Posterior Tibial Tendon Dysfunction and Controls Using Multiplanar Weight-Bearing Imaging or Conventional Radiography. J Bone and Joint Surgery Am. 2014; 96:e63:1-8.

Scientific Literature Review

Reviewed By: Kendra Anderson, DPM
Residency Program: Southern Arizona VA Health Care System

Podiatric Relevance: Posterior Tibial Tendon Dysfunction (PTTD) is a common cause of foot and ankle pain. It is a progressive deformity that if not treated in early stages can lead to deformity. Conventional radiographs are the gold standard in assessing Posterior Tibial Tendon Dysfunction but has limitations.

Methods: Twenty-three patients (ten male and thirteen female) with Stage II, III, and IV PTTD had conventional weight-bearing radiographs and multiplanar weight-bearing imaging performed. These were compared to ten control patients (eight females and two males). Thirteen parameters were measured on the multiplanar weight-bearing images: transverse talar-first metatarsal angle, talonavicular coverage angle, talonavicular uncoverage percentage, talocalcaneal angle, talar tilt, lateral gutter distance, subtalar joint impingement (recorded as present or absent), talofibular impingement (recorded as present or absent), sagittal talar-first metatarsal angle, talonavicular, angle, naviculocuneiform angle, talocalcaneal angle, and angle of talus with respect to the floor.  All but the lateral gutter distance and talofibular impingement were measured on the conventional weight-bearing radiographs. All parameters were measured by independent and blinded radiologists. For the statistical analysis, nonparametric Wilcoxon rank-sum was used for all continuous radiographic parameters in both modalities. The Fisher exact test was used for subtalar joint subluxation and talofibular impingement.  Intraclass correlation coefficient or kappa analysis was used to assess the correlation of the eleven common parameters between the modalities.  

Results: Six of the parameters for the multiplanar weight-bearing images were found to have significant differences between the patients with PTTD and the controls; they were transverse talar-first metatarsal angle, talonavicular uncoverage percentage, sagittal talar-first metatarsal angle, talonavicular angle, talocalcaneal angle, and the angle of the talus with respect to the floor. For the conventional weight-bearing radiographs only one parameter was found to be significant, lateral talar-first metatarsal angle. The intraclass correlation coefficient displayed agreement between both modalities on the eleven common parameters tested.

Conclusion: This study adds to the multiple previous studies demonstrating the efficacy and reliability of multiplanar weight-bearing imaging. Multiplanar weight-bearing imaging provides a move complete view of the changes of the foot that accompany PTTD and overcomes some of the limitations found with conventional weight-bearing radiographs. The time and cost to create the images in multiplanar weight-bearing imaging is a limiting factor for clinical use.