Complete traumatic backout of the blade of proximal femoral nail antirotation: a case report

Prospective assessment of trochanteric fracture managed by intramedullary nailing with controlled and limited blade back-out

INTRODUCTION

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.

MATERIAL AND METHOD

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.

RESULTS

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.

CONCLUSION

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.

Comparison of Baumgaertner and Chang reduction quality criteria for the assessment of trochanteric fractures

Objectives

Different criteria for assessing the reduction quality of trochanteric fractures have been reported. The Baumgaertner reduction quality criteria (BRQC) are relatively common and the Chang reduction quality criteria (CRQC) are relatively new. The objectives of the current study were to compare the reliability of the BRQC and CRQC in predicting mechanical complications and to investigate the clinical implications of the CRQC.

Methods

A total of 168 patients were assessed in a retrospective observational study. Clinical information including age, sex, fracture side, American Society of Anesthesiologists (ASA) classification, tip-apex distance (TAD), fracture classification, reduction quality, blade position, BRQC, CRQC, bone quality, and the occurrence of mechanical complications were used in the statistical analysis.

Results

A total of 127 patients were included in the full analysis, and mechanical complications were observed in 26 patients. The TAD, blade position, BRQC and CRQC were significantly associated with mechanical complications in the univariate analysis. Only the TAD (p = 0.025) and the CRQC (p < 0.001) showed significant results in the multivariate analysis. In the comparison of the receiver operating characteristic curves, the CRQC also performed better than the BRQC.

Conclusion

The CRQC are reliable in predicting mechanical complications and are more reliable than the BRQC. Future studies could use the CRQC to assess fracture reduction quality. Intraoperatively, the surgeon should refer to the CRQC to achieve good reduction in trochanteric fractures.

Cite this article: Bone Joint Res 2019;8:502–508.

A novel angle on helical blade placement in trochanteric fractures - The axis-blade angle

INTRODUCTION

For trochanteric fractures, helical blade placement is crucial to the prognosis of operations. Existing measurement methods used for blade placement include the Cleveland zone, the tip-apex distance (TAD), the calcar-referenced tip-apex distance (CalTAD), and the Parker's ratio. These methods all lack a direct view on blade direction. The current study proposed the axis-blade angle (ABA) to solve direction problem and investigated its clinical applicability.

METHODS

A retrospective study collected 156 patients between May 2014 and February 2018. The occurrence of mechanical complications was analyzed in relation to age, gender, fracture side, American Society of Anesthesiologists classification, fracture classification, reduction quality, bone quality, the Cleveland zone, the Parker's ratio, the TAD, the CalTAD, and the ABA.

RESULTS

119 patients, including 25 with mechanical complications, were suitable for full analysis. In the univariate analysis, the Cleveland zone, reduction quality, the TAD, the CalTAD and the ABA were statistically associated with mechanical complications. In the multivariate analysis, reduction quality (p = 0.008) and the ABA (p < 0.001; adjusted OR 0.86;95% CI 0.77 to 0.96) showed significant results, which indicated that reduction quality and the ABA were two independent influencing factors for mechanical complications. Calculation of the receiver operating characteristic (ROC) curve indicated that the ABA was a reliable predictor of mechanical complications at the cut-off of -10°.

CONCLUSIONS

The ABA provides instruction for the intraoperative adjustment of guide wire direction. Placing the helical blade with an ABA > -10° can effectively reduce the risk of mechanical complications.

Influence of different great trochanteric entry points on the outcome of intertrochanteric fractures: a retrospective cohort study

BACKGROUND

The Proximal Femoral Nail Antirotation (PFNA) system for treatment of intertrochanteric fractures is currently widely applied worldwide. However, even though the PFNA has produced good clinical outcomes, a poor introduction technique with an inappropriate entry point can cause surgical complications. Some researchers suggest improving clinical outcomes by modifying the entry point, but no research has focused on this issue. The purpose of the present study is to compare the clinical and radiological outcomes of two different trochanteric entry points for the treatment of intertrochanteric fractures using the PFNA system.

METHODS

From May 2010 to October 2015, a total of 212 elderly patients with intertrochanteric fractures who were treated with the PFNA-II system were included into this retrospective cohort study. Group LA (98 patients) was treated using a lateral anterior trochanteric entry point, and group MP (114 patients) was treated using a medial posterior trochanteric entry point. All patients underwent follow-up assessments at 1, 3, 6, and 12 months after surgery. Radiographic evaluation was based on the impingement, tip-apex distance (TAD) and the position of the helical blade within the femoral head. Clinical evaluation was based on the surgical time, fluoroscopy time, blood loss, hospital stay, visual analogue scale (VAS), thigh pain, and Harris hip score.

RESULTS

The impingement was significantly reduced (P = 0.011) in group MP. The helical blade positions were significantly lower (P = 0.001) in group MP. The TADs in group LA (22.40 ± 4.43) and group MP (23.39 ± 3.60) were not significantly different (P = 0.075). The fluoroscopy time of group LA (53.26 ± 14.44) was shorter than that of group MP (63.29 ± 11.12, P = 0.000). Five iatrogenic lateral proximal fractures and 3 helical blade cutouts occurred in group LA, but none occurred in group MP. At 1 and 3 months postoperation, the Harris hip scores were significantly higher in group MP (P = 0.001 and P = 0.000, respectively), and the VAS scores were lower (P < 0.05).

CONCLUSIONS

The medial posterior trochanteric entry point achieved excellent nail and helical blade position, reduced surgical complications, and enabled early hip function recovery but required longer fluoroscopy time than the lateral anterior trochanteric entry point.