Osteochondritis Dissecans

Purpose

Determine stability of osteochondritis dissecans

Tag(s)

 

Panel

 Musculoskeletal

Define-AI ID

 18050007

Originator

 Munib Sana

Panel Chair

 Jay Patti

Panel Reviewers

 Musculoskeletal Panel

License

 Creative Commons 4.0

Status Published

Clinical Implementation


Value Proposition

Osteochondritis dissecans (OCDs) are acquired disorders of bone in which there is fragmentation of the articular surface to varying degrees. Treatment can be conservative or surgical depending on how likely the OCD is to heal on its own. Unstable OCDs require surgical intervention, whereas stable OCDs are generally treated conservatively. Multiple MRI features are used to predict the stability of a lesion. Although late instability (a free-floating intra-articular fragment or thin line of fluid separating two pieces of bone) is easily identified, early instability is much harder to diagnose. An algorithm that can predict the likelihood of OCD instability would help guide the management of these patients with respect to early aggressive surgical intervention versus watchful waiting and continued MRI follow-up.

Narrative(s)

A 15-year-old male presents with knee pain, and an OCD is identified on the subsequent knee MRI. The algorithm evaluates the MRI and calculates the likelihood of instability. The radiologist is informed of this calculation at the time of interpretation.

Workflow Description

Images are obtained from modality and sent to PACS. The radiologist identifies an OCD and activates the AI engine. AI calculates OCD as a probability of instability. A message is sent to PACS from the engine with the classification information.

Considerations for Dataset Development


Procedures(s): {MRI: knee, ankle, elbow, shoulder}

Sex at Birth: {Male, Female}

 

Developmental Variants: Panner disease

 

Ossification Center: Normal developmental irregular ossification of the femoral condyles

 

Trauma: {Traumatic osteochondral defects}

Clinical Note: Traumatic osteochondral defects should not be included in the training data set. For example, most talar dome OCDs are post-traumatic.

 

Other: {Adult OCDs, Juvenile OCDs}

Clinical Note: Juvenile OCDs tend to heal with conservative management. Adult OCDs often progress to unstable fragments. Criteria for stable OCDs differs for juvenile and adult OCDs (ie, a juvenile OCD can have multiple small surrounding cysts and be stable, whereas an adult OCD with multiple small surrounding cysts is unstable).

Technical Specifications


Inputs

DICOM Study

Procedure

MRI: Knee, ankle, elbow, shoulder

Data Type

DICOM

Modality

MRI

Body Region

Extremities

 

Primary Outputs

Instability of OCD

RadElement ID

RDE240

Definition

Probability the OCD is unstable

Data Type

Numeric

Value Set

[0,1]

0 – Stable

1 – Unstable

Or indeterminate

Units

Probability that OCD is unstable

Secondary Outputs

Number of Cysts

RadElement ID

RDE241

Definition

Define number of cysts larger than 5mm.

Data Type

Numeric

Value Set

 

Units

Cysts

 

Size of Largest Cyst

RadElement ID

RDE242

Definition

Define volume of largest cyst

Data Type

Numeric

Value Set

 

Units

mm3

 

Fluid Signal Intensity Between Parent and Progeny Bone

RadElement ID

RDE243

Definition

If there is a line of signal equal to the pixel intensity value of joint fluid separating the parent and progeny bone, than this feature is considered positive.

Data Type

Numeric

Value Set

[0,1]
0-No intensity

1-Max intensity

Units

 

 

Integrity of Overlying Cartilage

RadElement ID

RDE244

Definition

Disruption of the cartilage surface

Data Type

Categorical

Value Set

0-Unknown

1-Focal breaks

2-Incongruity

Units

N/A

 

Integrity of Subchondral Bone Plate

RadElement ID

RDE245

Definition

Disruption of the cartilage surface

Data Type

Categorical

Value Set

0-Unknown

1-Focal breaks

2-Incongruity

Units

N/A


0-Unknown

1-Focal Breaks

2-Incongruity

0-Unknown

1-Focal Breaks

2-Incongruity

Future Development Ideas


Develop OCD detection on a plain film algorithm, which would help nonspecialists by running in the background. This would be valuable to orthopedics or in the case that a patient presents with other conditions the clinician to miss OCD.

Count and compare the number of cysts larger than 5mm to the operative report to determine instability at time of surgery or follow up MRIs to track stability over time. This could be a prospective or retrospective study.