Automated Leg Length Discrepancy Assessment on Radiographs
| Purpose | Quantify the lower extremity limb lengths on standing radiographs |
| Tag(s) | Limb length, leg length, discrepancy, lower extremity |
| Panel | Musculoskeletal Panel |
| Define-AI ID | 19050029 |
| Originator | David Sandman |
| Lead | David Sandman |
| Panel Chair | Jay Patti |
| Panel Reviewers | Musculoskeletal Panel |
| License | |
| Status | Public Commenting |
| RadElement Set | RDES102 |
Clinical Implementation
Value Proposition
Leg or lower extremity limb length discrepancy is a correctable problem affecting the pediatric and adult populations. Several methods of measuring the lower extremities have been described, each of which is prone to both intra-reader and inter-reader variability and can be a tedious task to complete. Automated measurements of the lower extremities can provide an accurate and reproducible measuring technique and result.
Narrative(s)
65 year old male with severe medial compartment osteoarthritis of the left knee. Total knee arthroplasty is planned, goals of which include attaining limb length equality and physiologic alignment. Weightbearing long-leg/lower extremity radiographs is ordered as part of the preoperative work-up. An algorithm measures the lower extremity lengths, auto-populating the data when a radiologist or other clinician reviews the study.
Workflow Description
Images obtained from the radiography unit are sent to PACS and the AI engine. The images are analyzed by AI. Coordinates of areas of interest are assessed using a measuring tool. Annotated measurements are saved as an image along with a summary of the measurement data set.
Considerations for Dataset Development
| Procedures(s) | { lower extremity limb length radiographs, long-leg radiographs} |
| View(s) | { Upright/standing-radiographs} |
| Sex at Birth | {Male,Female} |
| Age | [0,90] |
Technical Specifications
Inputs
DICOM Study
| Procedure | Long-leg study, weight-bearing lower extremity |
| Views | AP views |
| Data Type | DICOM |
| Modality | Radiograph |
| Body Region | Lower Extremity |
| Anatomic Focus | Hip, thigh, knee, leg, ankle |
Primary Outputs
Bilateral Lower Extremity Length
| RadElement ID | RDE636 |
| Definition | distance from top of femoral head to mid tibial plafond |
| Data Type | Numeric |
| Value Set | N/A |
| Units | Centimeters |
Bilateral Lower Extremity Length Coordinates
| RadElement ID | RDE637 |
| Definition | Line from top of femoral head to mid tibial plafond |
| Data Type | Coordinates |
| Value Set | N/A |
| Units | N/A |
Bilateral Femur Length
| RadElement ID | RDE638 |
| Definition | Distance from top of femoral head to medial condyle articular surface |
| Data Type | Numeric |
| Value Set | N/A |
| Units | Centimeters |
Bilateral Tibia Length
| RadElement ID | RDE639 |
| Definition | Distance from top of tibial intercondylar eminence to the mid tibial plafond |
| Data Type | Numeric |
| Value Set | N/A |
| Units | Centimeters |
Bilateral Bone Length
| RadElement ID | RDE640 |
| Definition | Femur length + tibia length |
| Data Type | Numeric |
| Value Set | N/A |
| Units | Centimeters |
Related Datasets
No known related public datasets at this time, please alert us if you know of any.