Related Experiment Video
Updated: Jul 16, 2025

The Microscopic Transcanal Approach in Stapes Surgery Revisited
Published on: February 16, 2022
The Impact of Supratrochlear Foramen on Humeri's Medullary Canal Diameter and Its Surgical Implications
Prabhjot K Chhabra1, Swati Yadav2, Rajesh K Jangir3
1Anatomy, Mahatma Gandhi Medical College and Hospital, Jaipur, IND.
Insights
The supratrochlear foramen (STF) is present in 15% of humeri and significantly narrows the medullary canal. This finding impacts surgical planning for pediatric elbow fractures, especially retrograde intramedullary nailing.
Area of Science:
- Orthopedic surgery
- Pediatric orthopedics
- Anatomy
Background:
- Supracondylar elbow fractures are common in children.
- Retrograde intramedullary nailing is a frequent treatment.
- Medullary canal anatomy and supratrochlear foramen (STF) presence affect nail stability.
Purpose of the Study:
- Determine the incidence and morphology of the STF.
- Compare medullary canal width in humeri with and without STF.
Main Methods:
- Examined 40 adult humeri for STF presence and morphology.
- Measured humerus dimensions and STF size.
- Radiographically measured medullary canal width at three levels.
- Compared canal width between humeri with and without STF using unpaired t-test.
Main Results:
- STF found in 15% of humeri (6/40).
- Humeri with STF showed smaller mean dimensions, but not statistically significant.
- Mean medullary canal width was significantly smaller in humeri with STF (p<0.05).
Conclusions:
- Humeri with STF have a significantly narrower medullary canal.
- This impacts retrograde intramedullary nailing in pediatric elbow fractures.
- Consider STF presence for surgical planning to prevent iatrogenic fractures and improve efficiency.
Abstract:
Introduction Supracondylar elbow fractures are prevalent in the pediatric age group, and retrograde intramedullary nailing of the humerus is a common treatment approach. The anatomy of the medullary canal and the presence of the supratrochlear foramen (STF) significantly influence the stabilization of the nail. This study aimed to determine the incidence and morphology of the STF and compare the width of the medullary canal in humeri with and without the STF. Methods We examined 40 humeri bones with fused humeral epiphyses for the presence of the STF obtained from the Department of Anatomy's osteology collections. We studied the morphology and measured the dimensions of the foramen. We then compared the morphometric characteristics of humeri bearing the STF with those without it. We also took radiographs of all bones and measured the medullary canal width at three levels. We compared the measured width of the medullary canal in humeri between those with an STF and those without. This analysis was performed using IBM SPSS Statistics version 27.0 (Armonk, NY: IBM Corp.) for Windows and an unpaired t-test. We considered p-values of less than 0.05 as statistically significant. Results We found the STF in six bones (15%) as follows: four on the left side and two on the right. Humeri with the STF had smaller mean head circumference, length, and shaft circumference than those without the foramen. However, this difference was not statistically significant (p>0.05). The mean width of the medullary canal in humeri with the STF was significantly smaller (p<0.05) than in bones without the STF. Conclusions Our study revealed that humeri with an STF present a significantly smaller diameter of the medullary canal, which can impact surgical procedures like retrograde intramedullary nailing. Clinicians should consider this when planning surgeries to avoid iatrogenic fractures and enhance procedural efficiency. Our data also suggest that larger humeri are less likely to have an STF, potentially influencing pre-surgical planning and fracture risk assessment.

