Anatomic Assessment of K-Wire Trajectory for Transverse Percutaneous Fixation of Small Finger Metacarpal Fractures: A Cadaveric Study

Transverse pinning of concomitant first and second metatarsal fractures using 1.5mm K-wires; case report and technical note

Introduction and importance

Here we represented a new technique of closed reduction and transverse pinning to address first metatarsal comminuted fractures in patients with a concomitant second metatarsal shaft fracture.

Case presentation

The first metatarsal comminuted fracture coincides with the second metatarsal simple fracture in this forefoot injury case. In a new technique, we used close reduction and percutaneous pinning (CRPP) in a transverse direction of pins to achieve a satisfactory outcome.

After performing traditional CRPP to fix the second metatarsal fracture, it served as physical support for the first metatarsal fixation. We drilled two 1.5mm pins through the first metatarsal bone at each proximal and distal side of the fracture site, transversely passed to the second metatarsal bone. Transverse pins came along from the first metatarsal medial side to the lateral. After six-week and 12-month follow-up, the patients had minimal pain with complete radiological and clinical fracture healing and no complication.

Clinical discussion

Here, internal fixation was unsuitable due to extensive soft-tissue injury and inadequate bone support. Despite the many advantages of external fixators, they have drawbacks that persuade us to perform our new technique: using K-wires for transverse pinning fixation of the first metatarsal fracture using an adjacent metatarsal as support. This minimally invasive approach is profitable because of its minimal soft tissue damage, affordable price, and convenient access.

Conclusion

The transfixation technique with K-wires is rarely used to treat metatarsal fractures. It may be helpful in similar cases of comminuted first metatarsal fracture with satisfactory outcomes.

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We introduced an applicable method for fixing comminuted first metatarsal fracture.

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Transverse pinning has appropriate clinical and radiological healing.

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Transfixation technique with K-wires is rarely used to treat metatarsal fractures.

Defining a Safe Zone for Percutaneous Screw Fixation of Posterior Malleolar Fractures

Posterior malleolar fractures require fixation to confer stability to the ankle. Although some have suggested that fractures involving less than 25% of the articular surface require no intervention, estimation of malleolar size on plain imaging is inaccurate. Some posterior malleolar fractures may be particularly suitable for posterior-to-anterior percutaneous screw fixation of the posterior malleolus via a posterolateral approach. We hypothesized that there may be a safe zone in the posterolateral ankle, identifiable with reliable anatomic landmarks, that might allow safe percutaneous screw placement for fracture fixation. The study protocol involved Step 1, in which multiple Kirschner wires were used in a single cadaveric specimen to attempt to identify a safe zone entry point in the posterior ankle, and Step 2, in which a single wire was used in each of six additional cadaveric specimens to test the ability to safely replicate the use of that entry point. In Step 1, a safe zone entry point was identified, located immediately lateral to the Achilles tendon and 1 cm above the level of the tip of the medial malleolus, when visualizing the posterior ankle. In Step 2, using these landmarks and an image intensifier, single wires were then successfully placed in the other six specimens without injury to any significant structure. If confirmed in clinical studies, the safe zone entry point that we have identified could potentially be used to facilitate posterior-to-anterior percutaneous fixation in patients with posterior malleolar fractures for whom open reduction may not be required or may be contraindicated.

Three-dimensional Printed Surgical Simulator for Kirschner Wire Placement in Hand Fractures

Supplemental Digital Content is available in the text.

Closed reduction and percutaneous pinning (CRPP) of hand fractures can be a deceptively challenging procedure that requires significant hands-on time to teach and learn. We created a realistic three-dimensional simulator that can be used for teaching junior residents the CRPP. Computer-aided design and computer-aided manufacturing (CAD/CAM) software was used to create a three-dimensional hand model incorporating several common hand fractures: Bennett’s fracture, transverse fifth metacarpal neck, and transverse second proximal phalanx. Three-dimensional printing was used to create molds in which the bones and soft tissue were poured. A polyurethane foam was utilized for the bones with iron incorporated to render them radiopaque, whereas silicone of varying viscosities was used for the soft tissues. Five plastic surgery residents and 5 consultants evaluated the model. Individuals then completed an anonymous 12-question survey evaluating the model based on realism, educational utility, and overall usefulness. Survey responses obtained from both residents and consultants were strongly in favor of the simulator. Average realism was graded as 4.48/5 by residents and 4.68/5 by consultants. Average educational utility was graded as 5/5 by residents and 4.95/5 by consultants. Average overall usefulness was graded as 5/5 by both groups. We created an anatomically accurate and realistic simulator for CRPP of hand fractures that was low cost and easily reproducible. Initial feedback was encouraging in regard to realism, educational utility, and overall usefulness.