Hip Pelvis.  2017 Sep;29(3):199-203. 10.5371/hp.2017.29.3.199.

Breakage of the Tail Portion of the Lag Screw during Removal of Proximal Femoral Zimmer Natural Nail: Report of Two Cases with Technical Notes

• Santoso A
• Choi IS
• Park KS
• Yoon TR

• KMID: 2389527
• DOI: http://doi.org/10.5371/hp.2017.29.3.199

Abstract

Proximal femoral cephalomedullary nailing is one of the treatments of choice for intertrochanteric fracture. Zimmer Natural Nail® (ZNN; Zimmer) is one of the alternatives. We report two cases of broken tail portion of the ZNN lag screw during the removal procedure. This may be the first reported cases in scientific literature with this pattern of failure. We report these cases to highlight one of the possible problems that could occur during removal of this implant which can possibly prolong the operation time significantly if the required device is not prepared.

Keyword

Hip fractures; Zimmer Natural Nail; Lag screw; Breakage

MeSH Terms

Hip Fractures
Tail*

Figure

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  Fig. 1 Preoperative pelvic radiograph showed a stable intertrochanteric fracture (A). (B) Immediate postoperative radiograph. Stable fracture fixation was obtained even though the nail was inserted through the fracture site. (C) Radiograph taken at 14 months postoperatively showed complete bone union, no sign of loosening around the lag screw and showed no breakage previous to removal surgery (arrow). (D) After the nail removal radiograph, bonegraft filling of the bone space was performed.

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  Fig. 2 The original Zimmer lag screw inserter and retaining shaft; this device was also used for lag screw removal (A). (B) Tip of the device after assembling the two parts.

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  Fig. 3 Two pieces of the broken part of the lag screw head (large arrow) and new slots were made to match the lag screw removal device tip using a high speed burr (small arrow) (A). (B) After assembling the lag screw removal device tip to the new slots. (C) Ilustration on the original Zimmer Natural Nail® lag screw tail portion for the area of new created slots with size 5×3 mm (dashed line); arrow indicate the area of breakage site.

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  Fig. 4 Anteroposterior hip radiograph before removal operation, a more protruded tail portion of the lag screw was noted (A). (B) Radiograph after removal of hardware. (C) An incomplete breakage of lag screw tail portion indicated by the arrow. It was also happened on the opposite part.

Reference

1. Kumar R, Singh RN, Singh BN. Comparative prospective study of proximal femoral nail and dynamic hip screw in treatment of intertrochanteric fracture femur. J Clin Orthop Trauma. 2012; 3:28–36.

2. Tyllianakis M, Panagopoulos A, Papadopoulos A, Papasimos S, Mousafiris K. Treatment of extracapsular hip fractures with the proximal femoral nail (PFN): long term results in 45 patients. Acta Orthop Belg. 2004; 70:444–454.

3. Gómeza PS, Díazb AF, Fernándeza JS. A simple removal method of a broken Proximal Femoral Nail (PFN). Injury Extra. 2006; 37:353–356.

4. Iwakura T, Niikura T, Lee SY, et al. Breakage of a third generation gamma nail: a case report and review of the literature. Case Rep Orthop. 2013; 2013:172352.

5. Park BJ, Cho HM. Removal methods for broken proximal femoral nails using ball tip guide wire: technical note and two cases report. J Korean Fract Soc. 2014; 27:315–320.

6. Kweon SH, Shin CH, Park JS, Choi BS. Breakage of cephalomedullary nail used in the treatment of proximal femur fractures: case report. J Korean Fract Soc. 2016; 29:42–49.

7. Ballal MS, Emms N, Thomas G. Proximal femoral nail failures in extracapsular fractures of the hip. J Orthop Surg (Hong Kong). 2008; 16:146–149.

8. Tantigate D, Riansuwan K, Mahaisavariya B, Sukjaitham K. Breakage of a lag screw of cephalomedullary nail: A technique of removal. Clin Orthop Surg. 2015; 7:261–263.

9. Zheng XL, Park YC, Kim S, An H, Yang KH. Removal of a broken trigen intertan intertrochanteric antegrade nail. Injury. 2017; 48:557–559.