# The CAPE TOWN modified squat and smile test: correlation with fracture union in long bone fractures of the lower limb

## TL;DR

A modified squat and smile test was evaluated for its ability to predict lower limb fracture healing in low-resource settings, but it did not correlate with radiological healing, though it did relate to quality of life.

## Contribution

The study evaluates the Cape Town modified squat and smile test as a potential tool for assessing fracture healing in resource-limited settings.

## Key findings

- The CTMSST did not correlate with radiological evidence of fracture union.
- Health-related quality-of-life measures correlated significantly with the CTMSST total score and its squat and smile domains.
- The support domain of the CTMSST showed no significant correlation with quality-of-life measures.

## Abstract

Assessing fracture union remains a significant challenge in low-resource settings, such as those across Sub-Saharan Africa. The original squat and smile test was developed as a potential surrogate measure for lower limb fracture union, aiming to reduce reliance on follow-up radiographs in environments with limited access to imaging. We evaluated the correlation between the (blinded) Cape Town modified squat and smile test (CTMSST) and fracture union following intramedullary nailing of lower limb long bone fractures.

We performed a retrospective review of prospectively collected data from the HIV in Orthopaedic Skeletal Trauma study.

A total of 180 patients with recorded CTMSST data were included in the analysis. There was no significant correlation between the CTMSST total score, or its individual domains (squat, support, and smile), and radiological evidence of fracture union. However, health-related quality-of-life measures (EQ-5D and disability rating index) showed a significant positive correlation with the total CTMSST score, as well as with the squat and smile domains (p < 0.05). No significant correlation was found between the support domain and these measures.

The CTMSST and its individual domains did not correlate with radiological fracture union following intramedullary nailing of lower limb fractures. However, the test showed significant positive associations with patient-reported outcome measures, suggesting potential utility in assessing functional recovery. Further prospective research is needed to validate the CTMSST and to explore its role in both clinical assessment and follow-up care in resource-limited settings.