Flexible intramedullary nails for the treatment of metacarpal fractures: A systematic review

Area of Science:

• Orthopedic surgery
• Traumatology
• Biomaterials engineering

Background:

• Metacarpal fractures are common hand injuries.
• Flexible intramedullary nails (FIN) allow for minimally invasive fixation and early patient mobilization.
• Comparing different FIN configurations is crucial for optimizing treatment outcomes.

Purpose of the Study:

• To systematically review and compare the post-operative outcomes of locked versus non-locked, and single versus double flexible intramedullary nails (FIN) in the treatment of metacarpal fractures.

Main Methods:

• A comprehensive literature search was conducted for English-language studies on acute metacarpal fractures treated with FIN.
• Included studies analyzed outcomes for 5th metacarpal neck fractures (locked vs. non-locked; single vs. dual non-locked) and 2nd-5th metacarpal fractures (locked vs. non-locked).
• Study quality was assessed using the National Institute for Health and JBI tools.

Main Results:

• Thirteen studies (649 fractures) were included, with most having a low risk of bias.
• No significant differences in overall complication rates were found between locked/non-locked and single/double non-locked FIN.
• Non-locked FIN showed reduced metacarpophalangeal joint penetration and delayed union but increased tendon irritation compared to locked FIN. Single non-locked nails had shorter operative times than double non-locked nails.

Conclusions:

• Flexible intramedullary nails (FIN) demonstrate low complication rates and excellent functional results for displaced metacarpal fractures.
• While complication profiles differ, locked or double nail configurations offer no clear advantage over a single non-locked FIN.
• Treatment decisions should consider the specific fracture pattern and potential risks associated with each FIN type.