Cement augmentation of the proximal femoral nail antirotation for the treatment of two intertrochanteric fractures - a comparative finite element study

Background There are concerns regarding initial stability and cutout effect in proximal femoral nail antirotation (PFNA) treating intertrochanteric fractures. No study have used finite element analysis (FEA) to investigate the biomechanics. This study aimed to compare the cutout effect, stress and displacement between stable (AO31-A1.3) and unstable (AO31-A2.2) intertrochanteric fractures treated by cement augmented PFNA. Methods Four femoral finite element models (FEMs) were constructed and tested under the maximum loading during walking. Non-augmented and augmented PFNA in two different intertrochanteric fractures were respectively simulated, assuming Tip Apex Distance (TAD) < 25 mm within each FEM. The cutout effect, stress and displacement between femur and PFNA were compared in each condition. Results Cutout effect was observed in both non-augmented femoral head and was more apparently in unstable intertrochanteric fracture model. After reinforced by bone cement, no cutout effect occurred in two models. Stress concentration were observed on medial part of intertrochanteric region and the proximal part of helical blade before augmented while were observed on femoral shaft and the conjunction between blade and nail after augmented in both FEMs. Displacement mainly appeared on femoral head and the helical blade tip before augmented while distributed moderately on intertrochanteric region and the upper part of nail after augmented in both FEMs. The maximum stress and displacement value of femur decreased both in stable and unstable model after augmented but was more significantly in the unstable one. The maximum stress and displacement value of PFNA increased both in stable and unstable model after augmented but was more significantly in the unstable one. Conclusion Our FEA study indicated that the cement augmentation of the PFNA biomechanically enhances the cutout resistance in intertrochanteric fracture, this procedure is especially efficient for the unstable intertrochanteric fracture.

AO/OTA 31A2 and 31A3 Intertrochanteric Fractures Managed by Proximal Femoral Nail Antirotation (PFNA)

Aim: To study the clinical and radiological outcome of unstable intertrochanteric fracture AO/OTA 31A2, 31A3 fixed by proximal femoral nail antirotation Study design: Descriptive cross sectional study. Place and duration of study: Department of Orthopedic Surgery and Traumatology, Pir Abdul Qadir Shah Jilani Institute of Medical Sciences, Gambat, Sindh from 1st January 2016 to 31st December 2019. Methodology: Forty four cases having intertrochanteric fracture AO/OTA 31A2, 31A3 with age ranging from 18 year to 55 year of either gender were selected; patients having close fracture, who were willing were included in the study, while patients older than 55 year and younger than 18 year, AO/OTA 31A1 fracture, open fracture, bilateral injuries, smoker, alcoholic, drug addicted, poly-trauma, pathological fracture and history of poor compliance, psychiatric disease were excluded. Results: There were 26(59.09%) males and 18(40.91%) females with mean age was 41.3±7.7 years. Regarding classification; AO/OTA 31A2 were 33 (75%), and 31A3 were 11 (25%). Mean time for union was 18.5±3.55 weeks. The average time of follow-up was 48.5±6.6 weeks. Harris Hip Score was excellent (90-100) in 31(70.45%), good (80-89) in 7(15.91%), fair (70-80) in 3 (6.81%) and poor (<70) in 3 (6.81%). Conclusion: Intramedullary device proximal femoral nail antirotation can be labelled as implant of choice for unstable intertrochanteric fractures AO/OTA 31A2, 31A3, with fruitful clinical and radiological outcomes, and with fewer complications. Hip Harris score was excellent-good in 86% of the patients. Key words: Proximal femoral nail antirotation (PFNA), AO/OTA 31A2, 31A3, Intertrochanteric, unstable fracture

Cemented hemiarthroplasty versus proximal femoral nail antirotation in the management of intertrochanteric femoral fractures in the elderly: a case control study

Background The treatment for intertrochanteric femoral fractures (IFF) among the elderly has been a controversial topic. Hemiarthroplasty (HA) and proximal femoral nail antirotation (PFNA) have their own advantages in the management of IFF. Hence, this study aims to compare and analyze differences in the effectiveness of both procedures on IFF among the elderly. Methods Overall, 99 patients (81.09 ± 8.29 years; 68 women) underwent HA or PFNA from January 2016 to May 2020. IFF were classified according to the Arbeitsgemeins für Osteosynthesefragen (AO) classification. The difference in underlying diseases, the American Society of Anesthesiologists (ASA) grade, Singh index, Harris scores, surgical time, intraoperative bleeding, postoperative blood test results, postoperative number of days to partially bearing weight, and survival outcomes were analyzed. Postoperative follow-ups were performed every 3 months. Results There was no significant difference in the AO classification, underlying diseases, ASA grade, Singh index, surgical time, and survival outcomes of the HA (45 patients) group and PFNA group (54 patients). The HA group was associated with earlier partial weight-bearing (HA: 4 [2 ~ 4.5] days, PFNA: 10 [8~14] days). It also had a higher total Harris score than the PFNA group at the 6-month follow-up visit (HA: 86.8 [81.90 ~ 90.23], PFNA: 83.48 [75.13 ~ 88.23]). Harris scores decreased more in patients aged ≥90 years in the PFNA group than in the HA group. The postoperative stress recovery rate in the HA group was faster based on postoperative blood test results. Conclusions PFNA and HA have good therapeutic effects in the treatment of IFF. The advantages of HA were reflected in short-term weight bearing, faster recovery from stress, and better joint function in the long term. This advantage is more obvious in the patient population aged over 90 years. Therefore, we suggest that surgeons should consider the benefit of HA in the treatment of IFF among the elderly. Trial registration Chinese Clinical Trial Registry, ChiCTR2000035814. Registered 17 August 2020, https://www.chictr.org.cn/showproj.aspx?proj=57083