Understanding the Orthopedic Push Pull Technique
In orthopedics, the push pull technique is a direct reduction method primarily used for displaced diaphyseal fractures, such as those of the fibula. The name refers to the two main phases of the procedure: first, using distraction to restore bone length (the "push" phase), and second, using compression to stabilize the fragments (the "pull" phase). This technique is crucial for ensuring proper anatomical alignment, which is vital for healing and long-term joint function, especially in complex ankle fractures where fibular length restoration is critical.
The Procedure Step-by-Step
- Initial Assessment and Incision: After proper patient positioning and anesthesia, a surgeon makes an incision to expose the fracture site. For ankle fractures, a lateral approach is common.
- Plate Application: A pre-contoured metal plate is temporarily attached to one of the main bone fragments, typically the distal (farther) fragment.
- Placement of the "Post Screw": A temporary screw, known as the "post screw," is inserted into the other main fragment, proximal (closer) to the plate. This screw acts as an anchor point for the next step. The choice between a unicortical (one cortex) or bicortical (both cortices) screw depends on the fracture's complexity and the required force.
- Distraction (The Push Phase): A bone spreader, or laminar spreader, is placed between the end of the plate and the post screw. The surgeon opens the spreader's tongs, applying a pushing force that distracts the fracture fragments, restoring the bone's original length.
- Achieving Reduction: While distracting, the surgeon can fine-tune the alignment. Intraoperative imaging, like fluoroscopy, is used to confirm that the bone is properly aligned in multiple planes.
- Compression (The Pull Phase): Once the correct length and alignment are achieved, a clamp (like a Verbrugge clamp) or other device is used to pull the plate end towards the post screw, applying compression across the fracture site for added stability.
- Final Fixation: Once reduced and compressed, permanent screws are placed through the plate to secure it to the bone. The temporary post screw is then removed, and the incision is closed.
Other Contexts for the Push-Pull Technique
While most commonly associated with orthopedic trauma, the push pull concept appears in other medical disciplines, leveraging similar principles of controlled, opposing forces.
Esophageal Food Impaction
In gastroenterology, a push-pull technique may be used during endoscopy to retrieve a bolus of impacted food. Instead of surgery, this involves an endoscope and specialized tools. In a push maneuver, the food bolus is gently pushed into the stomach. In a pull maneuver, the bolus is removed orally. A 2023 review of studies found comparable safety and effectiveness between the two methods, with the choice depending on the specific case and operator's judgment.
Orbital Surgery
Another, more specialized, application is in orbital surgery for managing certain lesions behind the eye. In this context, a "push-pull" approach describes a specific surgical strategy for resection, using specialized techniques to manipulate the lesion while protecting delicate surrounding structures.
Comparison of Reduction Techniques
| Feature | Push Pull Technique | Closed Reduction | Bridge Plating | Internal Fixation |
|---|---|---|---|---|
| Invasiveness | Requires open surgery with incisions | Non-surgical; manipulation is external | Less invasive than direct reduction for comminuted fractures | A broad category including push-pull, plates, screws |
| Best For | Displaced fractures requiring precise length restoration | Minimally or non-displaced fractures | Severely comminuted fractures where direct reduction is difficult | Holding bone fragments together internally while they heal |
| Process | Plate, post screw, spreader for distraction and compression | Physical manipulation from outside the body | Plate bridges the fracture site without direct fragment reduction | Inserting metal hardware (plates, screws, pins) into the bone |
| Key Advantage | High precision in restoring length and alignment | Less invasive, avoids surgery | Minimizes damage to soft tissues and blood supply | Offers strong, long-term stability |
Potential Complications and Recovery
As with any surgical procedure, there are risks associated with the orthopedic push pull reduction technique. These can include infection, nerve or blood vessel damage, and issues related to the implant hardware. The use of temporary screws has been studied for its potential risks, with research noting that unicortical screws can fail under higher forces compared to bicortical screws, potentially causing iatrogenic fracture. Your surgeon will discuss these risks with you based on your specific condition. Recovery involves post-operative immobilization in a cast or splint, followed by rehabilitation to regain strength and mobility. The timeline for recovery varies widely depending on the severity of the fracture and the patient's overall health.
Conclusion
The push pull reduction technique is a valuable surgical tool for treating complex, displaced fractures, particularly those in the ankle, by meticulously restoring bone length and alignment. Though invasive, its precision is often necessary to achieve optimal healing. Beyond orthopedics, the term also describes similar mechanical strategies in other fields like gastroenterology and orbital surgery. Understanding the specific context is key to grasping the technique's application and purpose in each discipline. For more information on orthopedic procedures, the AO Foundation offers comprehensive resources and surgical techniques.
