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Radical excision of malignant sacral tumors using a modified threadwire saw
Shunzo Osaka1, Osamu Kondoh, Yukihiro Yoshida
1Department of Orthopaedic Surgery, Nihon University School of Medicine, Tokyo, Japan. osamu-k@eva.hi-ho.ne.jp
Background:
Surgical treatment of malignant sacral tumors is difficult, and has a high rate of recurrence.
Objectives:
The aim of this study was to examine the wide margin of large and small malignant sacral tumors using a threadwire saw (T-saw).
Materials And Methods:
We devised a flexible silver guide probe connected to a modified threadwire saw by a suture thread to perform osteotomies. We operated on 10 patients with sacral tumors using this device. The sacral excisions were performed via a posterior approach by four surgeons (two on each side) working simultaneously.
Results:
We obtained a wide margin in all cases and no recurrence, after a mean follow-up of 4 years 2 months (range, 1 year 8 months-7 years 8 months). In one case, one nerve root on the right side was injured.
Conclusions:
Our new method is easier and faster than the conventional method in cases in which bilateral sacral nerve root canals require sectioning, and it produces a wide tumor margin.
Insights
A novel threadwire saw (T-saw) technique facilitates wide margins for malignant sacral tumors, preventing recurrence in a 4-year follow-up. This surgical approach offers a faster, easier alternative for complex sacral tumor resections.
Area of Science:
- Oncology
- Surgical Oncology
- Orthopedic Surgery
Background:
- Malignant sacral tumors present significant surgical challenges.
- High recurrence rates are common with conventional surgical treatments for these tumors.
Purpose of the Study:
- To evaluate the efficacy of a modified threadwire saw (T-saw) for achieving wide margins in both large and small malignant sacral tumors.
- To assess the T-saw's utility in complex sacral tumor resections.
Main Methods:
- A flexible silver guide probe connected to a modified threadwire saw via suture thread was developed for osteotomies.
- Ten patients with sacral tumors underwent surgical excision using this T-saw device.
- Simultaneous posterior approach with four surgeons (two per side) was employed for sacral excisions.
Main Results:
- All patients achieved a wide tumor margin.
- No recurrence was observed during a mean follow-up of 4 years and 2 months.
- One instance of nerve root injury occurred on the right side.
Conclusions:
- The T-saw method simplifies and accelerates osteotomies, especially when bilateral sacral nerve root canals require sectioning.
- This technique reliably produces wide tumor margins, crucial for preventing recurrence in malignant sacral tumors.
