Radiographic Evaluation of Congenital and Acquired Foot Deformities Calcaneal Pitch

Purpose

Characterization of congenital and acquired foot deformities on radiographs

Tag(s)

bilateral foot, foot, x-rays, radiographs, congenital foot, pes, feet, calcaneal pitch, weight-bearing

Panel

Pediatric

Define-AI ID

20010013

Originator

Pediatrics Panel
Lead Viet Le & Alex Towbin

Panel Chair

Steven Blumer

Panel Reviewers

Pediatric Panel

License

Creative Commons 4.0
Status Public Comment
RadElement Set RDES203 
                               

Clinical Implementation


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 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 calcaneal pitch. Additional use cases include the AP and lateral talocalcaneal angles, talo-1st metatarsal angle, talonavicular axis, 1st metatarsophalangeal angle, Meary’s angle, and the tibial-calcaneal angle.

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 simulated weight-bearing foot radiographs 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: calcaneal pitch, and normal vs. abnormal pitch

Considerations for Dataset Development


Procedures

X-ray, Foot

Radiograph, Foot

Gender

Male, Female

Age (years)

0-18

Views

Lateral

Technique

Weight-bearing,Simulated weight-bearing or Erect

Anatomy

Foot

Confounders

Cast, Splint, Brace, Non-weight-bearing, Supine

Technical Specifications


Input

 

DICOM Study

Procedure

X-ray, Foot Radiograph

Views

Lateral

Data Type

DICOM

Modality

X-ray

Body Region

Lower Extremity

Anatomic Focus

Foot


Primary Outputs

 

Calcaneal Pitch       

RadElement ID

RDE1337 

Definition

The angle between the calcaneal inclination axis and the supporting horizontal surface on a weight-bearing AP foot radiograph.

Data Type

Numerical

Value Set

0-90

Units

Degrees



Secondary Outputs 

 

Normal vs. Abnormal       

RadElement ID

RDE1338 

Definition

Normal for calcaneal pitch is between 20-30 degrees.

Data Type

Categorical

Value Set

  • normal (20-30 degrees)

  • abnormal (<20 degrees or >30 degrees)

Units

N/A



Pes Planus vs. Pes Cavus       

RadElement ID

RDE1339 

Definition

Calcaneal pitch measurement can determine a pes planus or pes cavus


Data Type

Categorical

Value Set

  • low pitch/pes planus (<20 degrees)

  • high pitch/pes cavus (>30 degrees)

Units

N/A

Future Development Ideas


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