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Effects of Removal and Reinsertion of Headless Compression Screws
Simon M Donald1, Rui Niu1, Christopher W Jones1
1Department of Hand Surgery and Peripheral Nerve Surgery, Royal North Shore Hospital, University of Sydney, Sydney, Australia.
The Journal of Hand Surgery
|November 16, 2017
Summary
Reversing headless compression screws causes immediate loss of compression. Replacing a too-long screw with a shorter, wider one can restore compression effectively.
Area of Science:
- Orthopedic surgery
- Biomechanical engineering
- Medical device research
Background:
- Headless compression screws are vital in orthopedic fixation.
- Maintaining compression is crucial for successful bone healing.
- Screw malposition can lead to loss of compression and fixation failure.
Purpose of the Study:
- To quantify compression loss in commonly used headless compression screws upon reversal.
- To evaluate the efficacy of using larger diameter screws to re-establish compression after initial screw malposition.
Main Methods:
- Three headless compression screw designs were tested in a bone model.
- Compression was measured using a load cell during controlled screw reversal.
- The ability to re-establish compression with a larger diameter screw was assessed after complete removal.
Main Results:
- All tested screws exhibited significant compression loss even after minimal reversal (30°).
- The Acutrak 2 Micro screw showed the highest initial compression but also the most rapid loss.
- Replacing a malpositioned screw with a shorter, larger diameter screw successfully restored compression levels.
Conclusions:
- Accurate screw length selection is critical to avoid compression loss.
- Reversing headless compression screws leads to immediate and significant loss of fixation.
- In cases of screw over-penetration, replacement with a shorter, wider screw is a viable solution to regain compression.
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