How much is too much? A guide to appropriately bending ball tip guide wires when using intramedullary nails for the treatment of lower extremity long bone fractures

Rethinking the Coronal Anatomic Axis of the Distal Tibia for Intramedullary Nail Placement: A Cadaveric Study

Background: Recent studies have reported that targeting a center-center position at the distal tibia during intramedullary nailing (IMN) may result in malalignment. Although not fully understood, this observation suggests that the coronal anatomic center of the tibia may not correspond to the center of the distal tibia articular surface. Questions/Purposes: To identify the coronal anatomic axis of the distal tibia that corresponds to an ideal start site for IMN placement utilizing intact cadaveric tibiae. Methods: IMN placement was performed in 9 fresh frozen cadaveric tibiae. A guidewire was used to identify the ideal start site in the proximal tibia and an opening reamer allowed access to the canal. Each nail was then advanced without the use of a reaming rod until exiting the distal tibia plafond. Cadaveric and radiographic measurements were performed to determine the center of the nail exit site in the coronal plane. Results: Cadaveric and radiographic measurements identified the IMN exit site to correspond with the lateral 59.5% and 60.4% of the plafond, respectively. Conclusions: Tibial nails inserted using an ideal start site have an endpoint that corresponds roughly to the junction of the lateral and middle third of the plafond. Further studies are warranted to better understand the impact of IMN endpoint placement on the functional and radiographic outcomes of tibia shaft fractures.

Comparison of free-hand fluoroscopic guidance and electromagnetic navigation in distal locking of tibia intramedullary nails

BACKGROUND

It is challenges for surgeon to position the distal locking screw of a tibia intramedullary nail. The traditional free-hand (FH) technique is related to the proficiency of surgeons and has a long learning curve. Furthermore, the radiation dose and the accuracy of screw placement should be taken into account. The new technology, the electromagnetic navigation system (ET), which is a radiation-free way to locate the position of the drill bit. The purpose of our study is to evaluate the results of the ET for distal locking screw of a tibia intramedullary nail and to compare the effects with the FH technique.

METHODS

Eighty-nine cases of tibia diaphyseal fracture who needed to treat by intramedullary nails were analyzed retrospectively, and were divided into 2 groups. Patients in navigation group (n = 54) were treated with intramedullary nail using the ET for distal locking, while other 35 patients using FH technique. Intraoperative fluoroscopy exposure times, screw insertion times, and healing times were recorded. The parameter was used for comparison in 2 groups.

RESULTS

The mean time of distal locking in the ET technique was significant less than that in the FH group (5.89 ± 2.02 minutes vs 12.26 ± 4.40 minutes) and the exposure time was reduced in ET group significantly (2.13 ± 0.73 seconds vs 19.09 ± 10.41 seconds). The healing time was proved to be coincident in FH group and ET group (15.34 ± 2.98w vs 16.06 ± 3.74w). The one-time success rate of distal locking nail operation was 100% in the navigation group, which was significantly higher than that in FH group (P < .05).

CONCLUSION

Compared with the FH technique, the ET for distal locking of tibia intramedullary nail has the advantages of high efficiency and short locking time without radiation.