Radiographic Evaluation of Congenital and Acquired Foot Deformities Tibial-Calcaneal Angle

Value Proposition

Multiple angles and measurements can be used to evaluate abnormal development of the foot, but the task of obtaining these can be cumbersome and time-intensive. An automated method for obtaining a series of angle measurements and bony relationships, which can eventually be used to characterize foot deformities, should improve the radiologists’ workflow.

For our use case(s), we will first focus on automating the measurement of a series of different angles and bony associations on foot radiographs, which can then be compiled to determine the presence vs. absence of a foot deformity. If present, our hope is for the algorithm to further diagnose/characterize the specific foot deformity. Ultimately, this may be expanded to include additional modalities, such as CT.

For this particular use case, we will limit our evaluation to measuring the tibial-calcaneal angle, which can be used to determine the midfoot/hindfoot alignment on lateral view, particularly for evaluation of clubfoot (talipes equinovarus). Additional use cases include the the AP talo-calcaneal and lateral talo-calcaneal angles, intermetatarsal angle, talo-1st metatarsal angle, 1st metatarsophalangeal angle, Meary’s angle, talonavicular axis and calcaneal pitch.

Narrative(s)

3 year-old female presents to the pediatrician with abnormal gait and in-toeing. Bilateral, weight-bearing 3-view foot radiographs are obtained for evaluation of foot deformities.

6 month-old male presents for contractures/abnormal positioning of the feet. Bilateral, 3-view foot radiographs with simulated weight-bearing are obtained for evaluation of foot deformities.

Workflow Description

Radiographs of the foot/feet are ordered, obtained, sent to PACS and the algorithm is triggered.

The algorithm delivers the following outputs: tibial-calcaneal angle, and normal vs. increased/decreased angle

Input

DICOM Study

Primary Outputs

Tibial-calcaneal Angle   

Secondary Outputs 

Normal vs. Decreased vs. Increased Tibial-calcaneal Angle       

As mentioned in the Value Proposition, future development ideas include

• Additional angle measurements

• Bony relationships in the foot

• Diagnosis of foot deformities if present (“diagnostic use cases”)

• Improvement from prior studies if comparisons are available

• Extrapolation to another imaging modality, such as CT

• Comparison with prior studies and documentation of change over time.