Abstract
Background: The first carpometacarpal joint is one of the joints prone to osteoarthritis in the upper limb. The aim of this study was to evaluate the accuracy and safety of first carpometacarpal joint injection using anatomical landmarks in the cadaver and to review previous studies.
Methods: In this study, 40 wrist specimens from 20 fresh cadavers without visible deformity or scars were studied. Four tactile techniques were used to inject the first carpometacarpal joint in different wrist positions (normal wrist position and wrist tilt towards the ulna). After injecting methylene blue into the joint, the specimens were dissected and the accuracy (staining of the joint) and safety (non-staining of adjacent neurovascular structures) were evaluated.
Findings: In specimens where the injection was performed in the proximal part of the first metacarpal bone, the injection was accurate in the normal wrist position in 9 cases and in the wrist tilt towards the ulna in 7 cases. In the distal snuffbox injection group, injection accuracy was observed in 8 samples (normal position) and 6 samples (wrist tilting towards the ulna). No statistically significant differences were observed between the different techniques and wrist positions. Also, none of the adjacent neurovascular structures were stained.
Conclusion: The findings of the study showed that injection into the first carpometacarpal joint without imaging guidance and using anatomical landmarks was safe and no significant differences in accuracy were observed between different injection techniques or different wrist positions.