Radioanatomical examination of the dorsal tubercle and surrounding regions for intraosseous infusions

Objectives: The aim of the study was to determine the soft tissue thickness overlying the dorsal tubercle and the relationship with adjacent anatomical structures in the distal radius for using this area as an alternative intraosseous route. Methods: Contrast-enhanced MR images of 56 adult patients (28 females, 28 males) without any wrist pathology were evaluated. The shape of dorsal tubercle and its relations with neighboring tendons and vessels with a diameter larger than 2 mm was identified on the axial T1-weighted sections. The soft tissue thickness above the most protruding point of the dorsal tubercle, the distance of the dorsal tubercle to closest tendon on the radial and ulnar sides, as well as its distance to the bone edges on the ulnar and radial sides, and the cortical bone thickness of the radius was evaluated. Results: The dorsal tubercle had sharp edges in 40 cases (71.4%), blunt in 12 cases (21.4%), and hump in 4 (%7.1) cases. Branches of dorsal venous plexus were found on its surface in 11 cases, extensor pollicis longus tendon only was found superficial to the dorsal tubercle in 7 cases while both extensor pollicis longus and dorsal venous branches were found in 2 cases. Conclusion: Dorsal tubercle of the distal radius can be considered as an important alternative route for IO infusions since it can be easily accessed without having a risk of injury to important structures, and can provide effective flow.