Hip Subsidence

Purpose

Measure subsidence in the hip following total hip arthroplasty

Tag(s)

 #THA

Panel

 Musculoskeletal

Define-AI ID

 18050004

Originator

 Munib Sana

Panel Chair

 Jay Patti

Panel Reviewers

 Musculoskeletal Panel

License

 Creative Commons 4.0

Status  Published

Clinical Implementation


Value Proposition

There are roughly 400,000 total hip arthroplasties (THAs) performed annually. Every patient has annual follow-up exams, which can add up to about 100 reads per day for an MSK radiologist who works with arthroplasty surgeons. Aseptic loosening and adverse local tissue reaction (ALTR) complicate a significant number of THAs and necessitate revision arthroplasty. These are indolent processes that, if not detected early, can lead to osteolysis or extensive tissue necrosis. Findings are not readily apparent on x-ray and require comparison with multiple prior exams to see progression of abnormality over time. AI meeting this use case would help to reduce false negative rate, patient risk, and medical legal risk for the radiologists. High-risk patients could be screened for elevated serum cobalt levels and sent to MRI for further evaluation. Delay in diagnosis could delay treatment for years.

Narrative(s)

A 65-year-old patient presents for annual follow-up THA x-ray. An algorithm evaluates the image and may also compare this exam with multiple prior exams. The algorithm detects if osteolysis is present to assist the radiologists in the interpretation of the patient’s THA status.

Workflow Description

The current image and accessible, prior hip x-rays are analyzed by the engine. Between the current image and images at least five years old or initial post-op film (if THA was performed less than five years ago), the engine can detect osteolysis. The images are returned to the radiologist at the time of interpretation.

Considerations for Dataset Development


Procedures(s): X-ray, hip

View(s): {AP, frog-leg lateral, cross-table lateral}

 

Sex at Birth: {Male, female}

 

Osteolysis Location: {Gruen zone 1, Gruen zone 7, Gruen zone 8, Gruen zone 14}

 

Interval Between Imaging (years): [0,20]

 

Comorbidities: {Calcar resorption, osteoporosis, subsidence, lucency}

Technical Specifications


Inputs

DICOM Study

Procedure

XRAY, Hip

Views

AP, frog-leg lateral, cross-table lateral

Data Type

DICOM

Modality

XRAY

Body Region

Pelvis

Anatomic Focus

Hip

 

Primary Outputs

Hip Subsidence

RadElement ID

RDE300 

Definition

Measure the amount of subsidence. Alert if subsidence is greater than or equal to 10 mm.

Data Type

Numeric

Value Set

[0,30]

Units

mm

Secondary Outputs

Total Hip Arthoplasty Status

RadElement ID

RDE301 

Definition

Status of the total hip arthroplasty

Data Type

Categorical

Value Set

0–Unknown

1–Present

2–Absent

Units

N/A