# Automatic Hip Fracture Identification and Functional Subclassification with Deep Learning

**Authors:** Justin D Krogue, Kaiyang V Cheng, Kevin M Hwang, Paul Toogood, Eric G Meinberg, Erik J Geiger, Musa Zaid, Kevin C McGill, Rina Patel, Jae Ho Sohn, Alexandra Wright, Bryan F Darger, Kevin A Padrez, Eugene Ozhinsky, Sharmila Majumdar, Valentina Pedoia  
**arXiv:** [1909.06326](https://arxiv.org/abs/1909.06326)  
**Date:** 2019-09-10  
**Summary page:** https://www.summarizepaper.com/en/paper/1909.06326v1/

## Key points

- Hip fractures are a significant cause of morbidity and mortality
- Timely diagnosis is crucial for successful treatment
- Researchers have developed an automatic identification and classification system for hip fractures using deep learning to improve outcomes by reducing diagnostic errors and decreasing time to operation
- The study involved reviewing hip and pelvic radiographs from 1118 studies, labeling 3034 hips via bounding boxes, and classifying them as normal, displaced femoral neck fracture, nondisplaced femoral neck fracture, intertrochanteric fracture, previous ORIF (open reduction internal fixation), or previous arthroplasty
- A deep learning-based object detection model was trained to automate the placement of the bounding boxes
- A Densely Connected Convolutional Neural Network (DenseNet) was then trained on a subset of the bounding box images
- The model's performance was evaluated on a held-out test set and compared to two groups of human observers: fellowship-trained radiologists and orthopaedists as well as senior residents in emergency medicine, radiology, and orthopaedics
- The binary accuracy for fracture of the model was 93.8%, with sensitivity of 92.7% and specificity of 95%
- Multiclass classification accuracy was 90.4%
- When compared to human observers under all conditions, the model achieved at least expert-level classification
- The deep learning model identified and classified hip fractures with at least expert-level accuracy while also improving human performance when used as an aid in diagnosis
- This innovative approach has great potential to reduce diagnostic errors in clinical practice while also saving valuable time in identifying hip fractures accurately

## Summary

Hip fractures are a significant cause of morbidity and mortality, and timely diagnosis is crucial for successful treatment. To improve outcomes by reducing diagnostic errors and decreasing time to operation, researchers have developed an automatic identification and classification system for hip fractures using deep learning. The study involved reviewing hip and pelvic radiographs from 1118 studies, labeling 3034 hips via bounding boxes, and classifying them as normal, displaced femoral neck fracture, nondisplaced femoral neck fracture, intertrochanteric fracture, previous ORIF (open reduction internal fixation), or previous arthroplasty. A deep learning-based object detection model was trained to automate the placement of the bounding boxes. A Densely Connected Convolutional Neural Network (DenseNet) was then trained on a subset of the bounding box images. The model's performance was evaluated on a held-out test set and compared to two groups of human observers: fellowship-trained radiologists and orthopaedists as well as senior residents in emergency medicine, radiology, and orthopaedics. The results showed that the binary accuracy for fracture of the model was 93.8%, with sensitivity of 92.7% and specificity of 95%. Multiclass classification accuracy was 90.4%. When compared to human observers under all conditions, the model achieved at least expert-level classification. Moreover, when used as an aid in diagnosis human performance improved significantly with aided resident performance approximating unaided fellowship-trained expert performance. In conclusion, this deep learning model identified and classified hip fractures with at least expert-level accuracy while also improving human performance when used as an aid in diagnosis. This innovative approach has great potential to reduce diagnostic errors in clinical practice while also saving valuable time in identifying hip fractures accurately.