# Ultrasonographic Evaluation of Canine Hip Dysplasia: Comparison with FCI Radiographic Scoring System

## TL;DR

This study explores using ultrasound to diagnose canine hip dysplasia, finding it can detect joint changes earlier than traditional X-rays.

## Contribution

The study introduces specific ultrasound parameters for evaluating canine hip dysplasia and compares them with radiographic standards.

## Key findings

- Ultrasound detected joint capsule thickening and femoral head abnormalities more clearly in dysplastic hips.
- Ultrasound parameters like CTFHi and FHNTs showed significant differences between normal and dysplastic hips.
- Ultrasound findings correlated strongly with progressive bone remodeling in dysplastic hips.

## Abstract

Canine hip dysplasia (CHD) is a very frequently occurring orthopedic disease in dogs which leads to pain, reduced mobility, and osteoarthritis. Radiography is the standard method for diagnosing and grading this disease, but this requires exposure to ionizing radiation and the use of deep sedation/anesthesia. In this study, we compared radiographic and ultrasonographic findings obtained from hip joints in dogs, and noted some specific ultrasound (US) signs. US detected thickening of the joint capsule, loss of femoral head shape, irregular head–neck transitions, and osteophytes, with changes more evident in dysplastic hip joints. These results may support the use of US as a potential tool in the diagnosis and monitoring of CHD.

Canine hip dysplasia (CHD) is a common orthopedic condition characterized by joint laxity, abnormal femoral head development, and osteoarthritis. Radiography remains the gold standard in diagnosis; however, ultrasonography (US) can detect changes in bone and periarticular soft tissue earlier in CHD progression. Forty-four hips from twenty-two adult dogs of various breeds were graded according to the Fédération Cynologique Internationale (FCI) grading system, and grouped as normal (A, B) or dysplastic (C, D, E). Canine hip US evaluation, using the ventral femoral head–neck approach, included the following: capsule thickness at the femoral head index (CTFHi) and capsule thickness at the femoral head–neck index (CTFHNi), both measured in mm/body weight × 100; femoral head shape score (FHSs) and femoral head–neck transition score (FHNTs); and osteophyte score (Os). These findings were evaluated qualitatively and then converted into numerical scores. Twenty-three hips were graded on the FCI system as being normal, and twenty-one as dysplastic. Median values of the US parameters CTFHi, CTFHNi, FHSs, FHNTs, and Os were 2.02, 7.79, 1.00, 1.00, and 0.00 in the normal-hips group, and 3.11, 9.32, 3.00, 2.00, and 1.00 in the dysplastic-hips group. Significant differences were observed between most US parameters evaluated. Strong associations were found between CTFHi, FHNTs, and Os, indicating progressive bone remodeling. These findings support US usage as a potential tool for CHD diagnosis and monitoring.