The main objective of the present prospective study was to assess mechanical complications associated with an original intramedullary nail with limited and controlled blade back-out in the treatment of trochanteric fracture.

All patients treated for trochanteric fracture in a single orthopedic/traumatologic surgery department over a 2-year period were included. Minimum follow-up was 6 months. Fracture stability was assessed on the AO criteria. The TFP® intramedullary nail has a monobloc helicoid blade. Its main feature is the controlled and limited blade back-out, optimizing fracture site compression in weight-bearing, without the drawback of excessive back-out. The main endpoint was onset of mechanical complications: cut-out, intra-articular protrusion, non-union, and pain. Baumgaertner's Tip-Apex Distance (TAD), blade centering within the femoral head and fracture reduction were also assessed.

One hundred thirty-eight patients (mean age, 83 years) were operated on, and 118 followed up. There were 9 mechanical complications (7.6%): 4 cut-outs (3.4%), 3 intra-articular protrusions (2.5%), 1 non-union (0.8%) and 1 case of pain (0.8%). TAD length was not associated with complications rate. Poor reduction was significantly associated with more complications (p=0.02), as was blade malpositioning. Mean back-out was 3.3mm, affecting 22 nails (19%). There were no complications in case of back-out, versus a 9.4% rate in absence of back-out, although this difference was not significant (p=0.21). There were no postoperative infections.

The TFP® nail is useful for fixation of trochanteric fracture, whether stable or unstable, due to its low rate of mechanical complications compared to the literature.