Inserting a straight (piriformis fossa entry) nail through the tip of the greater trochanter has been used for treating atypical femoral fractures (AFFs) with bowing. This study aimed to determine what degree of bowing can be successfully treated using a laterally shifted entry technique.
Twenty-three complete and six incomplete diaphyseal AFFs treated using the shifted entry technique were retrospectively analysed. Radiologic parameters and complications were evaluated. The complete AFFs were divided into two groups based on the severity of preoperative bowing: grade 0-II bowing and < 20° lateral bowing (minimal/moderate) and grade III bowing or ≥ 20° lateral bowing (severe). Comparison according to postoperative malalignment, a change of lateral or anterior bowing ≥ 5° was also performed.
Three complete AFFs in the minimal/moderate group showed malalignment, as did all in the severe group (p < 0.001). The change of bowing was greater for the severe group in lateral and anterior bowing (p = 0.004 and 0.001, respectively). A greater fracture gap was found on AP and lateral radiographs in the severe group (p = 0.044 and 0.026, respectively). In the comparison according to postoperative malalignment, a significant difference was found for the percentage of severe deformity (p < 0.001). All incomplete AFFs were united without complication.
Diaphyseal AFFs with grade 0-II bowing and < 20° anterior bowing were treated successfully by the shifted entry technique. However, postoperative malalignment was found in all cases of AFFs with severe bowing. Therefore, other techniques should be considered for AFFs with grade III bowing or ≥ 20° anterior bowing.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Lim SJ, Yeo I, Yoon PW et al (2018) Incidence, risk factors, and fracture healing of atypical femoral fractures: a multicenter case-control study. Osteoporos Int 29:2427–2435. https://doi.org/10.1007/s00198-018-4640-4
Kang JS, Won YY, Kim JO et al (2014) Atypical femoral fractures after anti-osteoporotic medication: a Korean multicenter study. Int Orthop 38:1247–1253. https://doi.org/10.1007/s00264-013-2259-9
Lee K-J, Min B-W (2018) Surgical treatment of the atypical femoral fracture: overcoming femoral bowing. Hip Pelvis 30:202. https://doi.org/10.5371/hp.2018.30.4.202
Park JH, Lee Y, Shon OJ et al (2016) Surgical tips of intramedullary nailing in severely bowed femurs in atypical femur fractures: simulation with 3D printed model. Injury 47:1318–1324. https://doi.org/10.1016/j.injury.2016.02.026
Teo B, Koh J, Goh S et al (2014) Postoperative outcomes of atypical femoral subtrochanteric fracture in patients on bisphosphonate therapy. Bone Jt J 96-B:658–664
Yue B, Ng A, Tang H et al (2015) Delayed healing of lower limb fractures with bisphosphonate therapy. Ann R Coll Surg Engl 97:333–338
Cha Y, Park CH, Yoo J-I et al (2020) Analysis of the changes in femoral varus bowing and the factors affecting nonunion for the treatment of femoral shaft fractures over 60 years old using piriformis fossa insertion intramedullary nailing. J Korean Fract Soc 33:65. https://doi.org/10.12671/jkfs.2020.33.2.65
Lai YS, Chau JYM, Woo SB et al (2019) A retrospective review on atypical femoral fracture: operative outcomes and the risk factors for failure. Geriatr Orthop Surg Rehabil 10:215145931986473. https://doi.org/10.1177/2151459319864736
Shon OJ, Yoon JY, Kim JW (2020) Clinical outcomes of using contralateral-side laterally bent intramedullary nails in atypical femur fractures with femoral bowing. Arch Orthop Trauma Surg. https://doi.org/10.1007/s00402-020-03524-1
Kim JW, Kim H, Oh CW et al (2017) Surgical outcomes of intramedullary nailing for diaphyseal atypical femur fractures: is it safe to modify a nail entry in bowed femur? Arch Orthop Trauma Surg 137:1515–1522. https://doi.org/10.1007/s00402-017-2764-1
Park YC, Song HK, Zheng XL, Yang KH (2017) Intramedullary nailing for atypical femoral fracture with excessive anterolateral bowing. J Bone Jt Surg - Am 99:726–735. https://doi.org/10.2106/JBJS.16.00760
Tan M, Siow JWX, Kwek EBK (2020) Intramedullary nailing of abnormally bowed atypical femoral shaft fractures: surgical technique. Arch Orthop Trauma Surg 140:353–357. https://doi.org/10.1007/s00402-019-03279-4
Shane E, Burr D, Abrahamsen B et al (2014) Atypical subtrochanteric and diaphyseal femoral fractures: second report of a task force of the American society for bone and mineral research. J Bone Miner Res 29:1–23. https://doi.org/10.1002/jbmr.1998
Yau WP, Chiu KY, Tang WM, Ng TP (2007) Coronal bowing of the femur and tibia in Chinese: its incidence and effects on total knee arthroplasty planning. J Orthop Surg (Hong Kong) 15:32–36. https://doi.org/10.1177/230949900701500108
Lee YK, Yeom J, Jang BW et al (2019) Reliability of measuring lateral bowing angle of the femur in patients with atypical femur fractures. J Orthop Surg 27:1–5. https://doi.org/10.1177/2309499019881475
Schilcher J, Koeppen V, Aspenberg P, Michaëlsson K (2015) Risk of atypical femoral fracture during and after bisphosphonate use: full report of a nationwide study. Acta Orthop 86:100–107. https://doi.org/10.3109/17453674.2015.1004149
Kim JW, Kim JJ, Byun YS et al (2017) Factors affecting fracture location in atypical femoral fractures: a cross-sectional study with 147 patients. Injury 48:1570–1574. https://doi.org/10.1016/j.injury.2017.05.033
Yoo H, Cho Y, Park Y, Ha S (2017) Lateral femoral bowing and the location of atypical femoral fractures. Hip Pelvis 29:127. https://doi.org/10.5371/hp.2017.29.2.127
Park YC, Yoon SP, Yang KH (2019) Localization of atypical femoral fracture on straight and bowed femurs. J Bone Metab 26:123–131. https://doi.org/10.11005/jbm.2019.26.2.123
Su XY, Zhao Z, Zhao JX, et al (2015) Three-dimensional analysis of the curvature of the femoral canal in 426 Chinese femurs. Biomed Res Int 2015: https://doi.org/10.1155/2015/318391
This study was approved by the institutional review board (application number: 2021–02-022).
Consent to participate
Consent for publication
The authors declare no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Below is the link to the electronic supplementary material.
About this article
Cite this article
Byun, SE., Cho, YH., Lee, YK. et al. Straight nail insertion through a laterally shifted entry for diaphyseal atypical femoral fractures with bowing: good indications and limitations of this technique. International Orthopaedics (SICOT) (2021). https://doi.org/10.1007/s00264-021-05212-0
- Atypical femoral fracture
- Femoral bowing
- Intramedullary nailing
- Entry point