Simulated weightbearing computed tomography for verification of radiographic staging of varus ankle osteoarthritis: a cross-sectional study

Abstract

Background Varus ankle osteoarthritis is classified using only weightbearing anteroposterior ankle radiographs; however, sagittal ankle alignment may also affect the position and extent of joint space obliteration. We hypothesized that the sagittal alignment of the ankle may also affect the position and extent of joint space obliteration visible on the coronal section; therefore, we identified the sites of joint space obliteration in patients with stage 3 varus ankle osteoarthritis for comparison with the sites observed on simulated weightbearing computed tomography and investigated the effects of anterior and posterior ankle subluxation. Methods Simulated weightbearing computed tomography scans of 83 ft with varus ankle osteoarthritis (26 stage 3a, 57 stage 3b) were performed to check for joint space obliteration in the ankle. Further classification as exhibiting either anterior, posterior, or no subluxation on weightbearing lateral radiographs was performed. Results Anterior, posterior, and no subluxation was seen in 5, 9, and 12 ankles among the 26 classified as stage 3a, respectively, and in 22, 12, and 23 ankles among the 57 classified as stage 3b, respectively. The mean tibial lateral surface angle on weightbearing lateral radiographs in stage 3a ankles was 75.6, 83.3, and 80.3 degrees in the anterior, posterior, and no subluxation groups, respectively; and 75.5, 86.6, and 82.7 degrees in stage 3b ankles (p < .05). In stage 3b ankles, widespread joint space obliteration was observed at the anterior distal articular surface of the tibia in all 22 ankles with anterior subluxation and at the posterior distal articular surface of the tibia in all 12 ankles with posterior subluxation. Conclusions Simulated weightbearing computed tomography revealed joint space obliteration at the anterior distal articular surface of the tibia in stage 3b ankles with anterior subluxation and at the posterior side in stage 3a and 3b ankles with posterior subluxation. In some patients with stage 3 varus ankle osteoarthritis, the obliteration of the joint space is difficult to evaluate accurately using only weightbearing anteroposterior radiographs; weightbearing lateral radiographs should also be performed.

Evaluation of Subtalar Joint’s Compensatory Function in Varus Ankle Osteoarthritis Using Globally Optimal Iterative Closest Points (Go-ICP)

“…The amount of pressure was determined to be 300 N according to the instrument manual. 7,8,10,11,16 Cross-sectional areas of the tibia, 50 mm from the tibial plafond, were adjusted in the axial plane on the CT to align all the scans (Figure 1). A perpendicular line was dropped from the central point of the axial tibial slice, 1 cm from the tibial plafond, and the point at which it met the ground was regarded as the origin.…”

Correction to: Simulated weightbearing computed tomography for verification of radiographic staging of varus ankle osteoarthritis: a cross-sectional study

“…Author details 1 Department of Orthopedic Surgery, Nara Medical University, 840 Shijo, Kashihara, Nara 634-8522, Japan. 2 Department of Orthopedics, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla 90110, Thailand.…”

Association between the distal tibiofibular syndesmosis types and ankle osteoarthritis in Chinese population: a retrospective study

“…At the same time, in the study of ankle OA, we should not be limited to the ankle, and the study of the force line of lower limbs is also extremely important. Some scholars have found that the TLS is greater or smaller will lead to subluxation or anterior dislocation of the talus, and change the stress distribution of the ankle, thus leading to ankle arthritis [14]. Therefore, we wondered whether the changes in the surface shape of the DTS might be associated with changes in ankle joint stress, leading to the occurrence of ankle arthritis.…”