Proximal Femoral Nail Antirotation Blade Research Articles

Is it advantageous to use the intraoperative compression option of proximal femoral nail antirotation in the treatment of osteoporotic intertrochanteric fractures? A retrospective comparative study.

The aim of this study was to retrospectively compare the radiological and clinical results of intertrochanteric fractures treated with proximal femoral nail antirotation (PFNA) that were either intraoperatively compressed or non-compressed. Ninety-four patients (64 female, 30 male; mean age = 77.6 years; age range = 68-81) who underwent intraoperative fracture compression (IOFC) (94 hip joints, group A) and 88 patients (64 female, 24 male; mean age = 77.1 years; age range = 67- 80) who underwent postoperative impaction (POI) alone (88 hip joints, group B) from2012 to 2017 met the following six conditions were observed for over 2 years: AO Foundation/Orthopaedic Trauma Association 31-A1 and 31-A2 trochanteric fractures; Singh index grade ≥ 3; positive or neutral medial cortical support position with slightly valgus reduction; possible compression of more than one cortical bone in the anterior or medial region of the fracture site based on preoperative imaging test; blade position within the center-center; andtip-apex distance of < 25 mm. During the follow- up periods, changes of pain and time to fracture union were evaluated clinically, and the lateral extension distance (for screw back-up) was evaluated radiologically which measuredbetween the lateral end of the screw and lateral edge of the intramedullary nail. The mean follow-up was 38.4 (range = 24-48) months in Group A and 36.7 (24-48) months in Group B. The mean operation time was 68 (range = 40-100) min in group A and 71 (range = 40-105) min in Group B (P = 0.521). Intraoperative blood loss was 78 (range = 50-110) mL in Group A and 81 (range = 50-100) mL in Group B (p=0.715). The mean fluoroscopy time was 2.8 (range = 2.2-3.5) min in Group A and 2.6 (range = 2.1-3.5) min in Group B (P = 0.631). The acute phase pain scores measured by visual analog scale at postoperative 3 months were 35.5 in Group A and 37.6 in Group B (P = 0.073). The lateral extension of the PFNA blade showed significant difference at 24 months after surgery (Group A, 3.6±3.1 mm; group B, 7.8±3.7 mm, P = 0.017). Fracture gaps after surgery were 1.8 (range = 0.5-2.5)mmin Group A and 2.6 (range = 0.7-4.6)mmin Group B, showing significant difference (P = 0.001). The average fracture union time was 16.7 (range = 14-20) weeks in Group A) and 19.7 (range = 16-22) weeks in Group B (P = 0.065). The mean Harris Hip Scores at postoperative 24 months were 84.3 (range = 65-100) in Group A and 85.5 (range= 69-100) in Group B (P = 0.545).p Conclusion: If all the six conditions are met, IOFC seems to appropriate for AO/OTA 31-A1 and 31-A2 intertrochanteric fractures with the smaller postoperative fracture gap and lateral protrusion of the blade, which may contribute to the shortening of fracture union periods. Level IV, Therapeutic Study.

Bone cement augmentation of femoral nail head elements increases their cut-out resistance in poor bone quality– A biomechanical study

The aim of this study was to analyze biomechanically the impact of bone cement augmentation on the fixation strength and cut-out resistance of Proximal Femoral Nail Antirotation (PFNA) and Trochanteric Fixation Nail Advanced (TFNA) head elements within the femoral head in a human cadaveric model with poor bone quality. Methodology: Fifteen pairs of fresh-frozen human cadaveric femoral heads were randomized to three sets of five pairs each for center-center implantation of either TFNA blade, TFNA screw, or PFNA blade. By splitting the specimens of each pair for treatment with or without bone cement augmentation, six study groups were created. All specimens were biomechanically tested under progressively increasing cyclic loading featuring a physiologic loading trajectory in a setup simulating a reduced intertrochanteric fracture with lack of posteromedial support. Number of cycles to 5° varus collapse was evaluated together with the corresponding load at failure. Results: Compared to the non-augmented state, all types of implants demonstrated significantly higher numbers of cycles to failure and load at failure following augmentation, p ≤ 0.03. Augmented TFNA blades resulted in highest numbers of cycles to failure and loads at failure (30492; 4049 N) followed by augmented PFNA blades (30033; 4003 N) and augmented TFNA screws (19307; 2930 N), p = 0.11. Augmented TFNA screws showed similar numbers of cycles to failure and loads at failure compared to both non-augmented TFNA and PFNA blades, P = 0.98.From a biomechanical perspective, bone cement augmentation significantly increases the cut-out resistance of instrumented TFNA and PFNA head elements and is a valid supplementary treatment option to these nailing procedures in poor bone quality.

RADIOLOGIC PREDICTIVE FACTORS FOR CUT OUT FAILURE OF PROXIMAL FEMORAL NAIL ANTI-ROTATION IN TREATMENT OF INTERTROCHANTERIC FRACTURES

Background: Proximal femoral fractures are the most common type of fracture among elderly patients. Moreover, half of the fractures are unstable types (AO31A2-A3). The aim of surgical treatments of these fractures is to achieve stable fracture fixation allowing early weight-bearing and returning to pre-fracture functional status. Even though the Tip Apex Distance (TAD) less than 25mm has been used to identify the appropriate position of the lag screw, little data has demonstrated the optimized TAD using a helical blade.Objectives: The study aimed to identify radiologic factors influencing fixation failure using a newly designed Proximal Femoral Nail Anti-rotation (PFNA)Methods: A total o 400 cases of low energy intertrochanteric fractures undergoing PFNA fixation were reviewed. Of these, 10 cases of fixation failure were further investigated determining the exact cause. Of 390 patients with successful outcomes treated using PFNA fixation, 20 cases were randomized as a control group. A comparative study was conducted between those with fixation failure group and control group.Results: The displacement in lateral view and sum of displacement between AP and lateral view of radiographs were noted to have significant differences between the group (p=0.002 and 0.015). No significant differences were found between the groups in terms of Neck Shaft Angle (NSA) and Tip Apex Distance (TAD) including migration of the PFNA blade in the Cleveland zone. Additionally, the cutoff point was determined as less than 0.91 using the sum of the distance of displacement of AP with specificity of 95% and sensitivity of 80%. Moreover, the lateral view of the radiographs was less than 1.42 with specificity of 80% and sensitivity of 80%.Conclusion: This study demonstrated that the displacement in lateral hip view and sum of the displacement in both AP and lateral hip view were alternative parameters measured to decrease failure rate in PFNA. These parameters may be useful as an alternative to decrease the mechanical failure of PFNA fixation.

The Effect of Valgus Reduction on the Position of the Blade of the Proximal Femoral Nail Antirotation in Intertrochanteric Hip Fractures.

BackgroundThe purpose of this study was to evaluate the quantitative association between the degree of reduction and the position of the blade of the proximal femoral nail antirotation (PFNA) in intertrochanteric hip fractures.MethodsFrom March 2009 to April 2015, 530 patients treated with PFNA for intertrochanteric hip fractures were retrospectively reviewed. Patients were divided into a valgus reduced group (group 1) and a non-valgus reduced group (group 2), and the “valgus reduced” was defined as valgus reduction over 5°. We compared the calcar referenced tip-apex distance (calTAD) and the area between the blade of PFNA and the medial cortex of the femoral neck between the two groups.ResultsThe calTAD was measured as 22.5 ± 4.1 mm in group 1 and 24.8 ± 3.8 mm in group 2 (p < 0.05). The area between the blade and the medial femoral neck was measured as 135.5 ± 49.8 mm2 in group 1 and 145.1 ± 54.8 mm2 in group 2 (p = 0.074). The area corrected for the length difference in the femoral neck was 0.55 ± 0.16 in group 1 and 0.79 ± 0.19 in group 2 (p < 0.05).ConclusionsValgus reduction resulted in less calTAD and inferior position of the blade at the femoral neck in the treatment of intertrochanteric hip fractures with PFNA.

The effect on outcomes of the application of circumferential cerclage cable following intramedullary nailing in reverse intertrochanteric femoral fractures.

The aim of this study was to evaluate the effect on union results of the application of cerclage cable around the lateral femoral wall (LFW) in postoperative fracture displacement. A retrospective evaluation was made of all the cases of reverse intertrochanteric fractures over a 7-year period in a trauma center. The study included 69 fractures treated with intramedullary nailing. The age of the patients, postoperative reduction quality and complications such as mechanical failure and non-union (1.4%) were obtained from the medical records. Changes in the neck-shaft angle, the amount of LFW displacement and telescoping of proximal femoral nail antirotation blades and lag screws were measured on anteroposterior and lateral radiographs. The functional evaluation of the Harris Hip Score was recorded at the final follow-up examination. The mean age of the patients was 56.31years (range 18-93years). Closed reduction was applied in 37 (53.7%) cases, open reduction in 10 (14.5%) and with cerclage cable in 22 (31.8%). Mechanical failure developed in 8 (11.5%) cases where cerclage cable was not used. In 2 of these 8 cases, open reduction was successful. In the patients where cerclage cable was applied, no mechanical failure developed and no case underwent revision surgery. In the cases where cerclage cable was not used, a significantly higher rate of telescoping was found. (p = 0.001). The application of cerclage cable was seen to significantly reduce the amount of LFW displacement (2.23mm vs 8.86mm) and shorten the time to partial weight bearing (p = 0.000). In reverse intertrochanteric fractures, the application of circumferential cerclage cable with cephalomedullary nailing contributes to primary stability and accelerates mobilization. Therefore, it can be considered a good option. It reduces the risk of failure internal fixation for intertrochanteric fracture.

Cement augmentation of the Proximal Femoral Nail Antirotation (PFNA) – A multicentre randomized controlled trial

IntroductionNew implant designs like the Proximal Femoral Nail Antirotation (PFNA) were developed to reduce failure rates in unstable pertrochanteric fractures in the elderly. Standardized implant augmentation with up to 6 mL of polymethylmethacrylate (PMMA) cement has been introduced to enhance implant anchorage by increasing the implant-bone interface in osteoporotic bone conditions. Biomechanically, loads to failure were significantly higher with augmentation. The primary objective of this study was to compare the mobility of patients with closed unstable trochanteric fractures treated by PFNA either with or without cement augmentation. Patients and methodsA prospective multicentre, randomized, patient-blinded trial was conducted with ambulatory patients aged 75 or older who sustained a closed, unstable trochanteric fracture. Surgical fixation had to be performed within 72 h after admission. Outcomes were evaluated at baseline, during surgery, 3 to 14 days after surgery, 3 months, 6 months, and 12 months after surgery. To evaluate the primary objective, patients’ walking speed was assessed by the Timed Up and Go (TUG) test. Secondary objectives included the analysis of implant migration assessed on radiographs, quality of life measured by the Barthel Index, mobility measured by the Parker Mobility Score, and complications. ResultsOf 253 randomized patients, 223 patients were eligible: 105 patients were allocated to the PFNA Augmentation group and 118 to PFNA group. At 3 to 14 days after surgery, there was no statistical significant difference in mean walking speed between the treatment groups. For the secondary objectives, also no statistical significant differences were found. However, no patient in the PFNA Augmentation group had a reoperation due to mechanical failure or symptomatic implant migration compared to 6 patients in the PFNA group. ConclusionsAugmentation of the PFNA blade did not improve patients’ walking ability compared to the use of a non-augmented PFNA but might have the potential to prevent reoperations by strengthening the osteosynthesis construct.

Cephalomedullary fixation for intertrochanteric fractures: an operative technical tip

Intertrochanteric fracture is the most common hip fractures in elderly population. Cephalomedullary fixation, including proximal femoral nail antirotation (PFNA) and gamma nail, is commonly used in the treatment of intertrochanteric fractures. One of difficulties encountered in operation is insertion of the guide wire to femoral head. The guide wire would always bend and flow superiorly away from femoral calcar, and the lag screw and helical blade will follow the track and get into superior part of femoral head, not into femoral calcar. Here, we are presenting a surgical technique to direct the guide wire to right track. When guide wire just passed the tack hole of the nail, the rod of nail was slightly tapped down further to allow the superior border of the tack hole to touch the guide wire. Therefore, the superior border of the tack hole can be used as presser to prevent the wire from deviating upward. Through this way, the lag screw and helical blade get a good purchase that docked at femoral calcar. After that, the rod of nail was pulled back a little to make the wire in the middle of the tack hole, which can facilitate the insertion of the PFNA blade or lag screw. Our experience demonstrated that this surgical technique reduced the intraoperative risk for patients.

Cement augmentation of hip implants in osteoporotic bone: How much cement is needed and where should it go?

Several studies proved the beneficial effect of cement augmentation of proximal femoral nail antirotation (PFNA) blades on implant purchase in osteoporotic bone. We investigated the effect of different localizations and amounts of bone cement. Polyurethane foam specimens were instrumented with a PFNA blade and subsequently augmented with PMMA bone cement. Eight study groups were formed based on localization and amount of cement volume related to the blade. All specimens underwent cyclic loading with physiological orientation of the force vector until construct failure. Foam groups were compared between each other and to a cadaveric control group. The experiments revealed a significant dependency of implant purchase on localization and amount of cement. Biomechanically favorable cement positions were found at the implant tip and at the cranial side. However, none of the tested augmentation patterns performed significantly inferior to the cadaveric benchmark. These findings will allow surgeons to further reduce the amount of injected PMMA, decreasing the risk of cement leakage or cartilage damage.

A biomechanical evaluation of proximal femoral nail antirotation with respect to helical blade position in femoral head: A cadaveric study

Objective:Despite new developments in the management of osteoporotic fractures, complications like screw cutout are still found in the fixation of proximal femur fractures even with biomechanically proven better implants like proximal femoral nail antirotation (PFNA). The purpose of this cadaveric study was to investigate the biomechanical stability of this device in relation to two common positions (center-center and inferior-center) of the helical blade in the femoral head in unstable trochanteric fractures.Materials and Methods:Eight pairs of human cadaveric femurs were used; in one group [center-center (C-C) group], the helical blade of PFNA was fixed randomly in central position both in anteroposterior and lateral view, whereas in the other group it was fixed in inferior one-third position in anteroposterior and in central position in lateral view [inferior-center (I-C) group]. Unstable intertrochanteric fracture was created and each specimen was loaded cyclically till load to failureResults:Angular and rotational displacements were significantly higher within the C-C group compared to the I-C group in both unloaded and loaded condition. Loading to failure was higher in the I-C group compared to the C-C group. No statistical significance was found for this parameter. Correlations between tip apex distance, cyclic loading which lead to femoral head displacement, and ultimate load to failure showed a significant positive relationship.Conclusion:The I-C group was superior to the C-C group and provided better biomechanical stability for angular and rotational displacement. This study would be a stimulus for further experimental studies with larger number specimens and complex loading protocols at multicentres.

Ex vivo evaluation of the polymerization temperatures during cement augmentation of proximal femoral nail antirotation blades

Previous studies have clearly demonstrated superior biomechanical behavior of augmented proximal femoral nail antirotation (PFNA) blades compared with nonaugmented ones with respect to implant cutout. Nevertheless, there is concern about thermal bone necrosis due to exothermic curing of polymethylmethacrylate (PMMA)-based bone cements. The objective of this study was to quantify the temperatures arising around perforated titanium PFNA blades when augmenting with PMMA. Cylindrical samples from six pairs of fresh frozen human cadaveric femoral heads implanted with a PFNA blade were placed in a 37°C water bath and augmented with 3 mL and 6 mL PMMA. During augmentation, temperatures were measured using six K-type thermocouples that were placed at controlled distances around the implant. With the help of high-resolution quantitative computed tomography images, the locations of all thermocouples with respect to the cement-bone interface were reconstructed. No temperatures higher than 45°C were measured in the interface region and the surrounding cement-free cancellous bone. In the same regions, the longest exposure time above 41°C was 8.5 minutes and was measured in a 6-mL sample. Average maximum temperature was significantly lower for the 3-mL group compared with the 6-mL group (p = 0.017). The results of this study suggest that augmentation of titanium PFNA blades is not associated with a risk of thermal bone necrosis when using up to 6 mL of PMMA. However, larger amounts of cement lead to higher temperatures. PMMA application should therefore be kept low to minimally alter the biological system.

Potential of polymethylmethacrylate cement-augmented helical proximal femoral nail antirotation blades to improve implant stability—A biomechanical investigation in human cadaveric femoral heads

Cement augmentation may improve fixation stability and reduce cut-out rate in the treatment of intertrochanteric hip fractures. The aim of this study was to compare the number of cycles to failure of polymethylmethacrylate (PMMA)-augmented helical blades with nonaugmented ones in human cadaveric femoral heads. Six pairs of cadaveric femoral heads were instrumented with a perforated proximal femoral nail antirotation blade. Within each pair, one blade was augmented using 3 mL of PMMA. All specimens underwent cyclic axial loading under physiologic conditions.Starting at 1,000 N, the load was monotonically increased by 0.1 N/cycle until construct failure occurred. To monitor the migration of the blade, anteroposterior radiographs were taken at 250 cycle increments. Nonparametric test statistics were done to calculate correlations and identify differences between study groups. Inducing failure required a significantly higher number of cycles in the augmented group (p = 0.028). Bone mineral density was significantly related with the number of cycles to failure in nonaugmented specimens (p 0.001, R2 = 0.97), but not in the augmented group (p = 0.91, R2 = 0.34). Implant augmentation with small amounts of PMMA enhances the cut-out resistance in proximal femoral fractures. Especially in osteoporotic bone, the procedure may improve patient care.

Biomechanical evaluation of bone-cement augmented Proximal Femoral Nail Antirotation blades in a polyurethane foam model with low density

BackgroundHelically shaped cephalic implants have proven their benefit to provide an improved stabilization of unstable hip fractures. However, cut out ratios up to 3.6% still occur. This in vitro study evaluated the biomechanical performance of a novel cement augmentation technique of the Proximal Femoral Nail Antirotation in surrogate femora. MethodsFour study groups were formed out of 24 polyurethane foam specimens with low density. Proximal Femoral Nail Antirotation blades were implanted, either non-augmented, or augmented using 3ml of injectable Polymethylmethacrylate bone-cement. The influence of implant mal-positioning was investigated by placing the blade either centered in the femoral head or off-centric in an anteroposterior direction. All specimens underwent cyclic loading under physiological conditions. Starting at 1000N, the load was monotonically increased by 0.1N/cycle until construct failure. Movement of the head was identified by means of optical motion tracking. Non-parametric test statistics were carried out on the cycles to failure, to compare between study groups. FindingsCompared to control samples; augmented samples showed a significantly increased number of cycles to failure (P=0.012). In the groups with centric position of the Proximal Femoral Nail Antirotation blade, cement augmentation led to an increase in loading cycles of 225%. In the groups with off-centric positioning of the blade, this difference was even more accentuated (933%). InterpretationCement augmentation of the Proximal Femoral Nail Antirotation blade with small amounts of bone-cement for treatment of osteoporotic hip fractures clearly enhances fixation stability and carries high potential for clinical application.

Comparison of proximal femoral nail antirotation blade and reverse less invasive stabilization system‐distal femur systems in the treatment of proximal femoral fractures

To compare the effects of proximal femoral nail antirotation blade (PFNA) and reverse less invasive stabilization system-distal femur (Liss-DF) systems in the treatment of proximal femoral fractures. Between June 2007 and October 2009, 41 proximal femoral fractures were treated, 22 with PFNA (group A) and 19 with reverse LISS-DF plates (group B). The time to starting full weight-bearing, fracture healing time, functional recovery (Parker and Palmer mobility score), neck-shaft angle discrepancies with the intact contralateral hip, preoperative American Society of Anesthesiologists (ASA) scores, the operation durations and amount of intraoperative bleeding were recorded and compared. The mean follow-up period was 11.2 months (range, 10-12 months). Compared with Group A, Group B showed a statistically longer mean time to bear full body weight and heal their fractures, but a smaller neck-shaft angle discrepancy (all P < 0.05). The groups were similar in ASA score, operation duration, amount of intraoperative bleeding and Parker and Palmer mobility score. Both PFNA and reverse Liss-DF were satisfactory for the treatment of proximal femoral fractures, but had different advantages. PFNA allowed earlier weight-bearing and accelerated fracture healing. Reverse Liss-DF more effectively avoided coxa vara and may be indicated for patients with very severe osteoporosis.

Mid-term outcomes after intramedullary fixation of peritrochanteric femoral fractures using the new proximal femoral nail antirotation (PFNA)

Background Controversy persists concerning the preferred treatment of peritrochanteric femoral fractures. The purpose of the present study was to evaluate the mid-term outcomes of the newly developed implants – proximal femoral nail antirotation (PFNA) for the stabilisation of this type of fracture. Methods Between April 2006 and March 2008, 169 patients with peritrochanteric femoral fractures were treated with PFNA. As many as 26 patients were excluded from the study. According to the Orthopaedic Trauma Association (OTA) classification system, the remaining 143 fractures were classified as 19 cases of AO/OTA 31A1 fractures, 83 cases of 31A2 fractures, 28 cases of 31A3 fractures and 13 cases of 31A combined with proximal 32 fracture or separate proximal 32 fracture. The mean age of these patients was 67 years (range, 20–93 years). The operative time, the overall fluoroscopy time, the duration of hospitalisation and the surgical complications were noted. Patients were followed up for a mean of 21 months (range, 12–36 months). Functional outcomes were assessed according to the Harris hip scoring system. Results Fifteen patients (10%) required open reduction. The mean duration of surgery (from the beginning of close reduction to wound closure) was 72 min with a range between 45 and 170 min. The mean fluoroscopy time was 164 s with a range between 92 and 396 s. The mean time of hospital stay was 15 days. Postoperative X-rays showed a good or acceptable reduction in 134 cases (94%), and an ideal implant position in 131 cases (92%). There were 12 (8%) postoperative complications. All patients except one healed their fractures without any implant-specific complication (bending, breaking of the implant, cut out of the PFNA blade, femoral head penetration of the blade or ipsilateral fractures of the femoral shaft at the tip of the implant). The average time to bone healing was 16 weeks (range, 12–25 weeks). At the time of the latest follow-up, 106 patients (74%) were restored to their preoperative mobility. The mean Harris hip score was 84 points (range, 46–100 points). A total of 106 patients (74%) had an excellent or good outcome. According to the patients and/or their caregivers, outcome was described as satisfactory in 120(84%) of the 143 patients, and 36(90%) of the 40 patients, who were more than 80 years old. Conclusion The results suggest that PFNA is a very effective and safe method in the treatment of different patterns of peritrochanteric femoral fractures. The fixation is adequate to maintain reduction over time even in osteoporotic bones.

PFNA and PFN in Intertrochanteric Fractures - Comparison Study of Sliding -

Purpose: This study compared sliding between (a) lag screws of PFN (Proximal Femoral Nail, AO synthes) and (b) the helical blade of PFNA (Proximal Femoral Nail Antirotation, AO synthes) for femoral intertrochanteric fractures. Materials and Methods: We include in our study thirty seven cases who were classified as AO/OTA type A1 femoral intertrochanteric fractures and who underwent hip operations between October 2006 and December 2008. There were 19 patients in the PFN group and 18 in the PFNA group. Degrees of sliding were also measured with postoperative radiology on last follow up compared with immediate postoperative radiology. Both groups were also compared with regard too walking ability using the method of Koval. Results: Average sliding was 5.0±2.3 mm for lag screws of the PFN group and 2.8±1.3 mm for the helical blade of the PFNA group. The difference was statistically significant (p=0.04). Ambulatory abilities were not statistically different (p=0.33). Conclusion: Patients in the PFNA group have less sliding of the implant, but their walking abilities are similar to patients in the PFN group.

Results of Treating Senile Osteoporotic Peritrochanteric Fracture with Proximal Femoral Nail Antirotation (PFNA)

Purpose: The purpose of this study was to evaluate the results of treating senile osteoporotic peritrochanteric fracture with proximal femoral nail antirotation (PFNA). Materials and Methods: Between November 2006 and December 2007, 21 patients older than 65 years of age with intertrochanteric and subtrochanteric fractures were treated with PFNA. The mean duration of follow-up was 12.9 months and the mean age was 74.5 years. Results: The mean operation time was 48.8 minutes (range: 25-90 minutes). The time to ambulation averaged 7.9 days. Eighty point nine percent (17 cases) of the patients returned to their previous walking status at 6 months after operation. The average T-score was -3.3. Eighteen cases (85.7%) achieved acceptable reduction and the mean time to radiologic bony union was 17.4 weeks. The average amount of PFNA blade sliding was 4 mm and the neck-shaft angle was changed to 1.3 degrees varus displacement at the final follow-up. The complications included pulmonary edema in 1 case and protrusion of the PFNA blade into the hip joint in 1 case. Conclusion: Because of the reduced operation time, favorable walking ability and low rate of complications, PFNA is an acceptable alternative for fixation of senile osteoporotic peritrochanteric fracture.

The AO/ASIF proximal femoral nail antirotation (PFNA): A new design for the treatment of unstable proximal femoral fractures

Introduction PFNA design compacts the cancellous bone to provide increased stability and has been bio-mechanically proven to retard rotation and varus collapse. Methods Between 2006 and 2007, 62 consecutive patients with unstable proximal femoral fractures were treated with the PFNA. Results Twenty males and 42 females with a mean age of 78 years (44–94) were reviewed. In 48 patients, the fracture resulted from a low energy injury. The majority of the fractures belonged to AO/ASIF types 31A2.3 (22) and 31A3.2 (29). Twelve patients required open reduction. The PFNA blade position was central in 52 patients with a mean tip-apex distance (TAD) of 12 mm (range 4–34 mm). Post-operatively, five patients died within 3 months and two patients were lost to follow-up. Forty-nine fractures united between 3 and 4 months. Four patients had delayed union. The PFNA blade cut out rate was 3.6%. Conclusions Unstable proximal femoral fractures were treated successfully with the PFNA. The PFNA blade appears to provide additional anchoring in osteoporotic bone. No results have been published on this new design.