Determining the Optimal Level of Proximal Locking Screw Insertion in Femoral Nailing

Abstract

Objectives: The aim is to investigate the optimum level of insertion for proximal locking screw in the proximal femurs.

Methods: The distance between the trochanteric fossa and lesser trochanter and the medial- lateral femur canal diameters 20 mm proximal and 20 mm distal to the lesser trochanter within an intervals of 10 millimeters on AP radiograms of 208 patients in both genders and different age groups were measured.

Results: The average distances between the trochanteric fossa and lesser trochanter level were 60.8 mm in male and 52.2 mm in female populations (p=0.000). The average femoral canal diameter at the level of the lesser trochanter was 29.2 ± 4.3 mm, whereas 10 mm proximal to the lesser trochanter  it was 39 ± 4.6 mm, the difference was statistically significant with  p=0.000.  

Conclusions: Lesser trochanter level is the optimal level for transverse proximal locking screw insertion since it contains the relatively narrowest canal in the proximal femur. Orthopedic surgeons should be aware of choosing the femoral nails with a proximal tip to proximal screw hole distance of a 61 mm in male and a 52 mm in female populations to increase three point bending resistance of proximal locking screw and to prevent early implant failure. 

Keywords

• Femur fracture; Intramedullary nailing; Proximal locking screw; Three point bending

Femur İntramedüller Çivilemede Proksimal Kilitleme Vidası Uygulaması Optimal Seviyesinin Saptanması

Abstract

Amaç; Çalışmanın amacı femur intramedüller çivilemede proksimal kilitleme vidası uygulamasının optimal yerleşim seviyesini saptamaktır.

Hastalar ve Metod: Her iki cinsiyetten ve farklı yaş gruplarından 208 hastanın kalça anteroposterior grafileri değerlendirilmiştir. Trokanter minor seviyesinin 20 mm distal ve 20 mm proksimal aralığı 10 mm lik aralıklara bölündü. Trokanterik fossa ile trokanter minor arası mesafe ve yukarıda belirlenen seviyeler arasında mediolateral femoral kanal çapları ölçüldü.

Sonuçlar: Trokanterik fossa ve trokanter minor arası ortalama mesafe erkeklerde 60,8 mm kadınlarda ise 52,2 mm olarak saptandı(p=0,000). Trokanter minor seviyesindeki ortalama femoral kanal çapı 29,2 ± 4,3 mm ve trokanter minörün 10 mm proksimalinde ise 39 ± 4,6 mm olarak ölçüldü. Fark istatistiksel olarak anlamlı bulundu(p=0,000).

Çıkarımlar: Trokanter minor seviyesi, rölatif olarak proksimal femurun en dar yeri olması nedeni ile transvers proksimal kilitleme vidası için optimal seviye olarak saptandı. Ortopedik cerrahların femoral çivi seçerken çivinin tepesi ile proksimal kilitleme vidası arası mesafenin –üç nokta bükülme direncinin yüksek olması ve erken implant yetmezliği riskini azaltması nedeni ile- erkeklerde 61 mm ve kadınlarda 52 mm olmasına dikkat etmesinde fayda vardır.

Keywords

• Femur kırığı; İntramedüller çivileme; Proksimal kilitleme vidası; Üç nokta bükülme testi

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