Skip to main content
Download PDF
  • Research article
  • Open access
  • Published:

Low filling ratio of the distal nail segment to the medullary canal is a risk factor for loss of anteromedial cortical support: a case control study

Journal of Orthopaedic Surgery and Research volume 17, Article number: 27 (2022) Cite this article

Abstract

Background

Anteromedial cortical support apposition (positive and/or neutral cortical relations) is crucial for surgical stability reconstruction in the treatment of trochanteric femur fractures. However, the loss of fracture reduction is frequent in follow-ups after cephalomedullary nail fixation. This paper aimed to investigate the possible predictive risk factors for postoperative loss of anteromedial cortex buttress after nail fixation.

Methods

A retrospective analysis of 122 patients with AO/OTA 31A1 and A2 trochanteric femur fractures treated with cephalomedullary nails between January 2017 and December 2019 was performed. The patients were classified into two groups according to the postoperative status of the anteromedial cortical apposition in 3D CT images: Group 1 with contact “yes” (positive or anatomic) and Group 2 with contact “No” (negative, loss of contact). The fracture reduction quality score, tip-apex distance (TAD), calcar-referenced TAD (Cal-TAD), Parker ratio, neck-shaft angle (NSA), and the filling ratio of the distal nail segment to medullary canal diameter in anteroposterior (AP) and lateral fluoroscopies (taken immediately after the operation) were examined in univariate and multivariate analyses. Mechanical complications were measured and compared in follow-up radiographs.

Results

According to the postoperative 3D CT, 84 individuals (69%) were categorized into Group 1, and 38 individuals (31%) were classified as Group 2. The multivariate logistic regression analysis showed that the poor fracture reduction quality score (P < 0.001) and decreasing filling ratio in the lateral view (P < 0.001) were significant risk factors for the loss of anteromedial cortical contact. The threshold value for the distal nail filling ratio in lateral fluoroscopy predicting fracture reduction re-displacement was found to be 53%, with 89.3% sensitivity and 78.9% specificity. The mechanical complication (varus and over lateral sliding) rate was higher in Group 2.

Conclusions

The fracture reduction quality score and the decreasing filling ratio of the distal nail to the medullary canal in the lateral view (a novel parameter causing pendulum-like movement of the nail) were possible risk factors for postoperative loss of anteromedial cortical support.

Background

Currently, trochanteric hip fractures (AO/OTA 31A) are primarily treated using cephalomedullary nails [1,2,3]. However, postoperative complications and mechanical failures are frequent, ranging from 3 to 22%[4,5,6], with complications including over collapse of the head–neck fragment with femoral neck shortening or varus, helical blade/lag screw lateral back-out, cut-out from the superior femoral head, cut-in through the central femoral head, fracture non-union, and implant nail breakage.

In 1980, Kaufer [7] proposed five factors that can predispose fixation complications and treatment failure: bone quality, fracture morphology, implant selection, implant placement, and, most importantly, fracture reduction quality. In 2015, Chang et al. [8] proposed the concept of anteromedial cortex-to-cortex support reduction to obtain secondary stability after limited telescoping. The apposition of anteromedial cortices between the head–neck and shaft was assessed by immediate postoperative fluoroscopy in both AP and lateral views. This factor was classified as exhibiting positive, neutral, and negative patterns [8]. In practice, positive and neutral cortical appositions are acceptable; however, none of the negative relationships in the AP or lateral view was acceptable before nailing [9,10,11].

However, the status of anteromedial cortical apposition in immediate postoperative fluoroscopy is not always in accordance with postoperative 3D CT images after head–neck sliding [12]. Generally, approximately 30% of cases lose the cortical contacts at the anteromedial corner and classified as being negative in follow-ups [12, 13] (Fig. 1); the loss are usually accompanied by over-sliding, femoral neck shortening and varus, and lower functional outcomes [9, 14]. Thus, the current study aimed to identify which factors could predict the postoperative loss of anteromedial cortical contact (negative) after cephalomedullary nailing.

Fig. 1
figure 1

An 87-year-old woman with trochanteric femur fracture that treated by closed reduction and cephalomedullary nail fixation. a The fracture type was classified as 2018 AO/OTA 31A1.2. b–d Immediate postoperative fluoroscopy in AP, lateral, and anteromedial oblique views showed a good reduction quality, with smooth anteromedial cortex apposition (neutral relation). e Postoperative 3D CT image showed loss of cortical contact at anteromedial inferior corner. The proximal neck was sagged posteriorly into the distal medullary canal (the red arrow). f, g Follow-up X-ray in 6 months. AP view showed the backout of the helical blade by over-sliding, and lateral view showed loss of cortical contact of the anterior cortex with posterior sagging. The red arrow indicates anterior swing of the nail; the yellow arrow indicates negative anteromedial cortex relation, thus a sagittal pendulum-like movement was happened with lower filing ratio of distal nail/canal diameter

Full size image

Methods

Patients and inclusion criteria

After Institutional Review Board approval, all patients who sustained trochanteric hip fractures from January 2017 to December 2019 were retrospectively reviewed. The inclusion criteria were as follows: (1) age at or over 60 years, (2) fresh trochanteric femur fractures, (3) AO/OTA-2018 classifications 31A1 and A2 [15, 16], (4) treated with intramedullary nail fixation, and (5) complete set of preoperative radiographs, intraoperative fluoroscopies, and postoperative CT scanning and 3D reconstructions, as well as having at least six months of postoperative follow-up images. The exclusion criteria were as follows: (1) 31A3 trochanteric fractures as this pattern has reversed fracture direction to the intertrochanteric line from greater to lesser trochanter, and (2) pathological fractures.

Patients were grouped according to the status of the full-range observed anteromedial cortex reduction in 3D CT as contact “yes” (Group 1, n = 84) and contact “no” (Group 2, n = 38). All of the radiographic measurements were evaluated in both groups. Patient demographic data and clinical characteristics were obtained from the medical records, including age, sex, side, American Society of Anaesthesiologists (ASA) score, and the severity of osteoporosis at the time of fracture. Osteoporosis was evaluated by using the contralateral radiograph according to the Singh Index.

Treatment protocol

All patients had the same treatment protocol, fixed by cephalomedullary nails (Proximal Femoral Nail Anti-rotation-II, PFNA-II). In this study, all the cases were fixed with a cephalomedullary nail with distal diameter of 10 mm. All of the procedures were performed with patients in the supine position on a fracture table under spinal or general anesthesia. Routine closed reduction maneuvers, including abduction, traction, and internal rotation were performed to obtain fracture alignment and confirmed by fluoroscopy in AP, lateral, and anteromedial oblique views. If closed reduction was not possible, especially in the lateral sagittal view, for example, head–neck posterior sag or displacement, intraoperative instrument manipulation (usually with the use of a bone hook) was performed through the lateral incision from the helical blade entry route. We did not accept any negative cortical apposition in either AP or lateral fluoroscopies before nailing. However, if re-displacement of fracture reduction occurred during the nailing process (usually in the lateral view), especially the helical blade had been hammered in, we accepted it and no further manipulation was attempted, especially in older frail patients [12].

Rehabilitation and follow-up

For rehabilitation after surgery, we have a protocol by combined evaluation of the postoperative radiographic stability score [17] and the patient’s physical capability and willingness. If it was judged as good (8 points) in stability score and patients’ capability, early weight-bearing standing and walking were encouraged within one week; otherwise, bed rest was recommended for one month, with no sitting and turning restrictions.

The follow-up time was set as at least six months, which was regarded as either fracture union or fixation failure [18, 19]. Our primary outcome included changes in fracture reduction in the anteromedial cortex. The secondary outcomes included healing and mechanical complications, including varus collapse, over-sliding, non-union, cut-out, cut-through, implant failure, and reoperation. Varus collapse was defined as NSA reduced by > 10°. Over-sliding was defined as helical blade lateral telescoping of ≥ 10 mm [20, 21].

Parameters measurement

As standard, three immediate postoperative fluoroscopies were obtained with the patient in fracture table after surgery, i.e., AP, lateral (axial), and 30-degree anteromedial oblique views. We measured fracture reduction quality [8], NSA, TAD [22], Cal-TAD [23], Parker ratio [24] (estimation of the blade position within the femoral head), and the distal nail filling ratio. For the measurements, the known proximal diameter of the nail was used to correct the image magnification.

Subsequently, the fracture reduction quality score was assessed according to the four-point method [8]. Combined with Garden alignment and anteromedial cortical relation in AP and lateral fluoroscopies, fracture reduction quality was classified as being good (4 points), acceptable (3 points), or poor (2 points and below) (Table 1).

Table 1 Quality of fracture reduction in unstable trochanteric hip fractures
Full size table

The filling ratio of the distal nail segment to the medullary canal was a new parameter and defined as the occupied proportion of the nail diameter to the inner medullary canal. Using Adobe Photoshop CC 2018 software, this variable was measured in standard AP (Fig. 2) and lateral fluoroscopies (Fig. 3) using the pixel ruler technique.

Fig. 2
figure 2

AP filling ratio was calculated in fluoroscopic image by the pixels of the distal nail (known as 10 mm, measured at 1 cm above the tip of the nail) to the pixels of the corresponding medullary canal diameter

Full size image
Fig. 3
figure 3

Lateral filling ratio was measured and calculated in fluoroscopic image

Full size image

The images from 3D CT were considered to be accurate and standard for fracture reduction assessments, as they can be rotated 360° to provide a full range view of the relationship between the head–neck fragment and the femoral shaft. The statistical analysis was performed based on the mean value of the data measured by the two gaugers. If divergence was encountered, we obtained a conclusion via group discussion with a senior professor.

Statistical analysis

SPSS 22.0 software (SPSS Inc., Chicago, IL, USA) was used for the statistical analyses. Continuous data were presented as means and standard deviation (SD). Categorical data were presented as counts and percentages. The univariate logistic regression analysis was performed to assess the risk factors for the loss of anteromedial cortical support. Variables with a P-value < 0.10 were further included in the multivariate analysis. A P-value less than 0.05 was defined as being statistically significant. The receiving operating characteristic (ROC) curve for distal nail filling ratio in lateral fluoroscopy was used to calculate the area under the curve. The best threshold value of the distal nail filling ratio in lateral fluoroscopy was used to predict loss of anteromedial cortical support.

Results

There were 34 males (28% of the sample) and 88 females (72% of the sample), with an average age of 83.0 years. The right side was affected in 63 patients (52%), and the left side was involved in 59 (48%). The AO/OTA-2018 classification identified 45 cases (37%) as type A1 and 77 cases (63%) as type A2.

Of the 122 patients included in this study, all patients had a positive or neutral cortex-to-cortex reduction in the AP and lateral immediate postoperative fluoroscopic views. The fracture reduction quality score was 4 points (good) in 87 cases (71%) and 3 points (acceptable) in 35 patients (29%). The 1-point loss in most cases was due to the residual gap between the head–neck fragment and shaft, which was larger than one cortex thickness. Finally, postoperative 3D CT full-range images revealed that 84 cases (69%) were categorized as having true anteromedial cortex contact (positive or anatomic, Group 1), and 38 cases (31%) were categorized as having lost contact (negative, Group 2).

Univariate and multivariate analysis

From the univariate logistic regression analysis, no significant differences were found concerning age, sex, side injured, ASA score, Singh index, helical blade TAD, Cal-TAD, NSA, and Parker ratio in the AP view. There were significant differences in AO/OTA classification (P = 0.045), reduction quality score (P < 0.001), Parker ratio in the lateral view (P = 0.012), nail filling ratio in the AP (P < 0.001) and lateral views (P < 0.001). Furthermore, in the multivariate analysis, only the distal nail filling ratio in the lateral view (P < 0.001) and fracture reduction quality score (P < 0.001) were considered to be significant predictive factors for the postoperative loss of anteromedial cortex contact (Table 2).

Table 2 Logistic regression model to detect possible risk factors for losing cortex-to-cortex support
Full size table

Mechanical complication

No patient exhibited cut-out, cut-in, fracture non-union, or nail broken characteristics for the follow-up analysis. The mechanical complication details of varus collapse and excessive lateral sliding are shown in Table 3.

Table 3 Mechanical complications
Full size table

ROC curve predicting cortex contact change

The ROC curve was used to estimate a threshold value that can predict losing of anteromedial cortical support. The criterion for alteration was 53% for filling ratio of the distal nail segment to the medullary canal in the lateral view for balancing sensitivity (89.3%) and specificity (78.9%) (Fig. 4).The area under the curve (AUC) was 0.919 for the filling ratio in the lateral view and 0.808 for the reduction quality.

Fig. 4
figure 4

Area under the curve (AUC) was 0.919 for the filling ratio of the distal segment to medullary canal on the lateral view (95% confidence interval 0.867 to 0.972) and 0.808 for the reduction quality score (95% confidence interval 0.714 to 0.901). The recommended lateral filling ratio of the distal nail segment to medullary canal for balancing sensitivity and specificity was 53 (%)

Full size image

Discussion

Our study enrolled 122 geriatric trochanteric hip fractures fixed with short trochanteric femoral nails. All patients had a positive or neutral anteromedial cortex reduction in the AP and lateral views on immediate postoperative fluoroscopy. Postoperative 3D CT full-range images revealed that 38 cases (31%) lost their cortical contact. In both the univariate and multivariate analyses, the fracture reduction quality score and decreasing distal nail filling ratio in the lateral view were significant risk factors for predicting the loss of anteromedial cortical contact.

Risk factors for complication and failure

Five major factors have been recognized as predisposing fixation complications and treatment failure, including bone quality, fracture morphology, implant selection, implant placement, and, most importantly, fracture reduction quality [7]. However, of these five factors, only three factors can be controlled by the surgeon. For implant selection, more surgeons now prefer the use of intramedullary nails [25,26,27]. For the position of the helical blade in the femoral head, the TAD, Cal-TAD, and Parker ratios provide good guidance and are practiced in daily work [3, 28,29,30]. For the quality of fracture reduction, there has been a recent tendency for surgeons to pay more attention to the anteromedial cortex rather than to the posteromedial lesser trochanter, as has been previously described [31]. In addition, Kim et al. [32] showed that greater trochanter separation was a risk factor for posterior sagging, which was caused by the instability of the posterior coronal fragment. Parry et al. [33] demonstrated that calcar gapping and fracture classification were related to over-sliding of lag screws. Ciufo et al. [34] confirmed that lateral wall fracture, neck-shaft malreduction, and residual basicervical gapping were related to lag screw cut-out. Our study concluded that the fracture reduction score and the filling ratio of the distal nail segment to the medullary canal in the lateral view are closely associated with the anteromedial cortex buttress alteration. Therefore, in addition to fracture reduction with anteromedial cortex support, we also recommend that surgeons choose a nail diameter as thick as possible, provided that it can be manually inserted without femoral shaft reaming.

Anteromedial cortical support reduction

It is well-known that fracture reduction quality is of paramount importance and is the first prerequisite factor for the successful treatment of trochanteric femur fractures [35]. Anteromedial cortical support reduction provides mechanical stability to share loads from the implant and biological environments in fracture healing [13, 36]. However, redisplacement of the head–neck fragment after cephalomedullary nailing is still a common phenomenon, which leads to the transition of primarily good/acceptable fracture reduction quality changes into a poor category and causes varus deformity, femoral neck shortening, healing complications, or even implant failure [8, 37].

Anteromedial cortex-to-cortex support reduction was first introduced in 2015 by Chang and colleagues for unstable pertrochanteric femur fractures [8]. It involves a pattern of non-anatomical functional buttress reduction. It is specific for the proximal femur, as it relates to the NSA, and when various implant devices with sliding mechanisms are used for fixation. Controlled fracture impaction via limited telescoping provides secondary axial and torsional stability between the head–neck fragment and the femur shaft [38].

A full description of anteromedial cortical support reduction or cortex-to-cortex contact involves the assessment in three fluoroscopic views, i.e., the AP view (for the medial cortex), the lateral view (for the anterior cortex), and the 30-degree oblique view (for the anteromedial inferior corner cortices) [39]. The relationship between the head–neck fragment and the femoral shaft, which describes the position of their cortical layers or the trend in their changes of position after sliding along the implant axis (usually by 130°), is evaluated and classified into three categories (positive, neutral, and negative) for both medial and anterior cortical appositions.

We do not accept any negative cortical relations in AP, lateral, or oblique fluoroscopic views before cephalomedullary nailing in clinical practice. Re-manipulation is performed by using a closed maneuver or inserted instruments (such as a bone hook) to dig out the head–neck from its intramedullary position. However, redisplacement may occur during surgery, and there is usually no opportunity for readjustments in older frail patients after nailing.

Predictors for loss of anteromedial cortex reduction

Anteromedial cortical support is favorable for secondary stability after limited lateral sliding between head–neck fragments to the femoral shaft. However, several factors may interfere with sliding movement and change the final cortical apposition at the anteromedial inferior corner. These factors include (but are not limited to) the bearing and residual space between the head–neck fragment and femoral shaft, the ability to initiate head–neck sliding, the direction of sliding, the rotation and/or tilting during sliding, the external rotation of the femoral shaft (which may open a gap and step between the two anterior cortices), and the pendulum-like movement of the nail in the medullary canal [37].

The residual space between the head–neck and femoral shaft in the medial and/or lateral cortices is a major predictive factor. Typically, one cortex thickness is used as the criterion, and a residual gap/space larger than one cortex thickness (especially in the anterior region) is considered a significant risk factor. As the head–neck fragment obliquely slides in the inferior lateral direction, a larger gap likely predicts the loss of cortical contact. In this cohort study of patients who were evaluated as possessing acceptable fracture reduction quality (i.e., 3 points), the loss of 1 point in most cases was due to the larger residual gap/space between the anterior cortices in lateral fluoroscopy.

Pendulum-like movement in short nails is another risk factor. The distal interlocking screw acts as a pivotal point, leading to the proximal nail with the head–neck fragment toggling back and forth in both coronal (AP view) and sagittal (lateral view) directions. The amplitude of the proximal movement is determined by the tip segment length distal to the locking screw, the width of the medullary canal, and whether there is a posterior coronal fragment involving the lesser trochanter and posteromedial cortex. In the clinic, this phenomenon is especially prominent for short nails with significantly shorter nail tip lengths distal to the interlocking screw and with a larger posterior banana-like fragment, which consists of the posterior coronal components of the greater trochanter, the posterior crest, the lesser trochanter, and the posteromedial cortex. Chang et al. [17] described this phenomenon and recommended using full-length nails to prevent this deformity.

As the proximal femoral shaft canal diameter in the sagittal plane is usually larger than that in the coronal plane, the distal nail filling ratio is inversely smaller in the sagittal plane than in the coronal plane, which indicates that pendulum-like movement may occur more frequently and severely in the sagittal plane and result in the proximal nail and head–neck fragment shifting backward (Fig. 5). Clinically, this phenomenon may occur with the following two conditions: (1) detachments of the lesser trochanter and posteromedial cortex (A2.3 in 2018-AO/OTA classification) [40], whether it occurs in a large banana-like posterior coronal fragment or a comminuted pattern [16], and (2) a lower filling ratio of the distal nail to a capacious medullary canal. We referred to the pendulous wave as a swing tail effect.

Fig. 5
figure 5

Schematic drawing to show loss of cortex to cortex apposition with low filling ratio in lateral view. a Smooth anterior cortical relation after nailing fixation. b Pendulum-like movement in sagittal plane leads to the proximal nail and head–neck fragment shifts backward, and results in a posterior sag of the anterior cortex. c The head–neck fragment loses its cortical buttress from the femoral shaft during sliding

Full size image

Recently, several studies have focused on the effects of distal nail diameter. Cheung et al. [41] studied the distal nail diameter (10 mm vs. 11 mm) in short nails and found no differences in the postoperative complications. In a biomechanical study, Ceynowa et al. [42] reported that the large discrepancy in the diameters of the medullary canal (reamed to 18 mm) and the distal part of the nail (11 mm) would result in the tip of the nail migrating laterally as far as causing an impingement to the lateral cortex. However, these authors did not consider the filling ratio concept. Durusoy et al. [43] revealed that the nail diameter made a difference in intramedullary nail movement by using biomechanical tests. A low filling ratio has been associated with varus collapse progress and cut-out complications. However, the research has only explored the match between the diameter of the nail and the intramedullary canal in the coronal plane. The clinical influence of the filling ratio of the nail in the sagittal plane has not been previously reported.

In our opinion, suffusion of the distal nail to the medullary space will enhance the stability by preventing pendulum-like movement, especially in the sagittal plane. It will contribute to the overall stability of the fracture that is fixed with the intramedullary nail. Therefore, the negative transformation of the support status would not be easy to trigger. In addition, two distal screws would also be a benefit for preventing the pendulum-like movement. Distal stability combined with anteromedial contact would be beneficial for reducing the incidence of lateral sliding and varus collapse, as was observed in our follow-up analysis.

Study limitations

There were several limitations of this study. First, it was limited by the retrospective analysis itself. Second, the CT examination was not regularly performed for all the patients, the sample of enrolled patients was small. Additionally, 3D CT was deemed to be the standard in judging anteromedial cortex-to-cortex contact. Therefore, patients who lacked CT data were excluded. We also recognized that the filling ratio of the distal nail in the medullary space only plays a limited role in intramedullary nail fixation. Further studies with large samples and prospective design with clinical follow-up data would be beneficial for demonstrating more reliable conclusions.

Conclusions

In conclusion, for trochanteric femur fractures treated with intramedullary nails, the filling ratio of the distal nail to the medullary canal in the lateral view plays a role in predicting the maintenance of anteromedial cortex-to-cortex supports. A filling ratio over 50% on the lateral view may be regarded as the threshold for preventing pendulum-like movement of the nail in the medullary canal and for eliciting a benefit in mechanical complications. Our conclusions remind us of the existing possible fixation impact of the nail diameter matching the medullary space. It is recommended that thicker nails be used without femoral shaft reaming.

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Abbreviations

TAD:

Tip-apex distance

Cal-TAD:

Calcar-referenced TAD

NSA:

Neck-shaft angle

AP:

Anteroposterior

ASA:

American Society of Anaesthesiologists

ROC:

Receiver operating characteristic

AUC:

Area under the curve

References

  1. Ciaffa V, Vicenti G, Mori CM, Panella A, Conserva V, Corina G, et al. Unlocked versus dynamic and static distal locked femoral nails in stable and unstable intertrochanteric fractures. A prospective study. Injury. 2018;49(Suppl 3):S19–25.

    PubMed  Google Scholar 

  2. Liu W, Liu J, Ji G. Comparison of clinical outcomes with proximal femoral nail anti-rotation versus InterTAN nail for intertrochanteric femoral fractures: a meta-analysis. J Orthop Surg Res. 2020;15(1):500.

    PubMed  PubMed Central  Google Scholar 

  3. Barla M, Egrise F, Zaharia B, Bauer C, Parot J, Mainard D. Prospective assessment of trochanteric fracture managed by intramedullary nailing with controlled and limited blade back-out. Orthop Traumatol Surg Res. 2020;106(4):613–9.

    PubMed  Google Scholar 

  4. Geller JA, Saifi C, Morrison TA, Macaulay W. Tip-apex distance of intramedullary devices as a predictor of cut-out failure in the treatment of peritrochanteric elderly hip fractures. Int Orthop. 2010;34(5):719–22.

    PubMed  Google Scholar 

  5. Bonnaire F, Lein T, Fulling T, Bula P. Reduced complication rates for unstable trochanteric fractures managed with third-generation nails: gamma 3 nail versus PFNA. Eur J Trauma Emerg Surg: Off Publ Eur Trauma Soc. 2020;46(5):955–62.

    Google Scholar 

  6. Lee YK, Yoon BH, Hwang JS, Cha YH, Kim KC, Koo KH. Risk factors of fixation failure in basicervical femoral neck fracture: which device is optimal for fixation? Injury. 2018;49(3):691–6.

    PubMed  Google Scholar 

  7. Kaufer H. Mechanics of the treatment of hip injuries. Clin Orthop Relat Res. 1980;146:53–61.

    Google Scholar 

  8. Chang SM, Zhang YQ, Ma Z, Li Q, Dargel J, Eysel P. Fracture reduction with positive medial cortical support: a key element in stability reconstruction for the unstable pertrochanteric hip fractures. Arch Orthop Trauma Surg. 2015;135(6):811–8.

    PubMed  PubMed Central  Google Scholar 

  9. Yamamoto N, Imaizumi T, Noda T, Inoue T, Kawasaki K, Ozaki T. Postoperative computed tomography assessment of anteromedial cortex reduction is a predictor for reoperation after intramedullary nail fixation for pertrochanteric fractures. Eur J Trauma Emerg Surg: Off Publ Eur Trauma Soc. 2021. https://doi.org/10.1007/s00068-021-01718-9.

    Article  Google Scholar 

  10. Kristan A, Benulic C, Jaklic M. Reduction of trochanteric fractures in lateral view is significant predictor for radiological and functional result after six months. Injury. 2021;52(10):3036–41.

    PubMed  Google Scholar 

  11. Li SJ, Kristan A, Chang SM. Neutral medial cortical relation predicts a high loss rate of cortex support in pertrochanteric femur fractures treated by cephalomedullary nail. Injury. 2021;52(11):3530–1.

    PubMed  Google Scholar 

  12. Chang SM, Zhang YQ, Du SC, Ma Z, Hu SJ, Yao XZ, et al. Anteromedial cortical support reduction in unstable pertrochanteric fractures: a comparison of intra-operative fluoroscopy and post-operative three dimensional computerised tomography reconstruction. Int Orthop. 2018;42(1):183–9.

    PubMed  Google Scholar 

  13. Tian KW, Zhang LL, Liu C, Chen XT, Chen K. The positive, neutral, and negative cortex relationship in fracture reduction of per/inter-trochanteric femur fractures. Int Orthop. 2020;44(11):2475–6.

    PubMed  Google Scholar 

  14. Kim CH, Kim HS, Moon DH. Additional reduction screw fixation technique for pertrochanteric hip fractures: a novel method to prevent excessive sliding in cephalomedullary nail surgery. Hip Pelvis. 2021;33(3):162–6.

    PubMed  PubMed Central  Google Scholar 

  15. Meinberg EG, Agel J, Roberts CS, Karam MD, Kellam JF. Fracture and dislocation classification compendium-2018. J Orthop Trauma. 2018;32(Suppl 1):S1–170.

    PubMed  Google Scholar 

  16. Song H, Chen SY, Chang SM. What should be filled in the blank of 31A2.1 in AO/OTA-2018 classification. Injury. 2020;51(6):1408–9.

    PubMed  Google Scholar 

  17. Chang SM, Hou ZY, Hu SJ, Du SC. Intertrochanteric femur fracture treatment in Asia: what we know and what the world can learn. Orthop Clin N Am. 2020;51(2):189–205.

    Google Scholar 

  18. Palm H, Jacobsen S, Sonne-Holm S, Gebuhr P, Hip Fracture Study Group. Integrity of the lateral femoral wall in intertrochanteric hip fractures: an important predictor of a reoperation. J Bone Jt Surg Am. 2007;89(3):470–5.

    Google Scholar 

  19. Ganczak M, Chrobrowski K, Korzen M. Predictors of a change and correlation in activities of daily living after hip fracture in elderly patients in a community hospital in Poland: a six-month prospective cohort study. Int J Environ Res Public Health. 2018;15(1):95.

    PubMed Central  Google Scholar 

  20. Li C, Xie B, Chen S, Lin G, Yang G, Zhang L. The effect of local bone density on mechanical failure after internal fixation of pertrochanteric fractures. Arch Orthop Trauma Surg. 2016;136(2):223–32.

    PubMed  Google Scholar 

  21. Choo SK, Oh HK, Ko HT, Min DU, Kim Y. Effectiveness of controlled telescoping system for lateral hip pain caused by sliding of blade following intramedullary nailing of trochanteric fracture. Injury. 2017;48(10):2201–6.

    PubMed  Google Scholar 

  22. Baumgaertner MR, Solberg BD. Awareness of tip-apex distance reduces failure of fixation of trochanteric fractures of the hip. J Bone Jt Surg Br. 1997;79(6):969–71.

    CAS  Google Scholar 

  23. Kuzyk PR, Zdero R, Shah S, Olsen M, Waddell JP, Schemitsch EH. Femoral head lag screw position for cephalomedullary nails: a biomechanical analysis. J Orthop Trauma. 2012;26(7):414–21.

    PubMed  Google Scholar 

  24. Parker MJ. Cutting-out of the dynamic hip screw related to its position. J Bone Joint Surg Br. 1992;74(4):625.

    CAS  PubMed  Google Scholar 

  25. Li H, Wang Q, Dai GG, Peng H. PFNA vs. DHS helical blade for elderly patients with osteoporotic femoral intertrochanteric fractures. Eur Rev Med Pharmacol Sci. 2018;22(1 Suppl):1–7.

    CAS  PubMed  Google Scholar 

  26. Zang W, Liu PF, Han XF. A comparative study of proximal femoral locking compress plate, proximal femoral nail antirotation and dynamic hip screw in intertrochanteric fractures. Eur Rev Med Pharmacol Sci. 2018;22(1 Suppl):119–23.

    CAS  PubMed  Google Scholar 

  27. Babhulkar S. Unstable trochanteric fractures: Issues and avoiding pitfalls. Injury. 2017;48(4):803–18.

    PubMed  Google Scholar 

  28. Murena L, Moretti A, Meo F, Saggioro E, Barbati G, Ratti C, et al. Predictors of cut-out after cephalomedullary nail fixation of pertrochanteric fractures: a retrospective study of 813 patients. Arch Orthop Trauma Surg. 2018;138(3):351–9.

    PubMed  Google Scholar 

  29. Li S, Chang SM, Jin YM, Zhang YQ, Niu WX, Du SC, et al. A mathematical simulation of the tip-apex distance and the calcar-referenced tip-apex distance for intertrochanteric fractures reduced with lag screws. Injury. 2016;47(6):1302–8.

    PubMed  Google Scholar 

  30. Wang Z, Liu Y, Li S, Wang X, Liu C, Tang X. How to get better TAD? Relationship between anteversion angle of nail and position of femoral neck guide pin during nailing of intertrochanteric fractures. BMC Musculoskelet Disord. 2020;21(1):512.

    CAS  PubMed  PubMed Central  Google Scholar 

  31. Yoon YC, Oh CW, Sim JA, Oh JK. Intraoperative assessment of reduction quality during nail fixation of intertrochanteric fractures. Injury. 2020;51(2):400–6.

    PubMed  Google Scholar 

  32. Kim KH, Kang MS, Lim EJ, Park ML, Kim JJ. Posterior sagging after cephalomedullary nailing for intertrochanteric femur fracture is associated with a separation of the greater trochanter. Geriatr Orthop Surg Rehabil. 2020;11:2151459320946013.

    PubMed  PubMed Central  Google Scholar 

  33. Parry JA, Sapp T, Langford JR, Koval KJ, Haidukewych GJ. Variables associated with lag screw sliding after single-screw cephalomedullary nail fixation of intertrochanteric fractures. J Orthop Trauma. 2020;34(7):356–8.

    PubMed  Google Scholar 

  34. Ciufo DJ, Zaruta DA, Lipof JS, Judd KT, Gorczyca JT, Ketz JP. Risk factors associated with cephalomedullary nail cutout in the treatment of trochanteric hip fractures. J Orthop Trauma. 2017;31(11):583–8.

    PubMed  Google Scholar 

  35. Biber R, Berger J, Bail HJ. The art of trochanteric fracture reduction. Injury. 2016;47(Suppl 7):S3–6.

    PubMed  Google Scholar 

  36. Shao Q, Zhang Y, Sun GX, Yang CS, Liu N, Chen DW, et al. Positive or negative anteromedial cortical support of unstable pertrochanteric femoral fractures: a finite element analysis study. Biomed Pharmacother. 2021;138:111473.

    PubMed  Google Scholar 

  37. Carr JB. The anterior and medial reduction of intertrochanteric fractures: a simple method to obtain a stable reduction. J Orthop Trauma. 2007;21(7):485–9.

    PubMed  Google Scholar 

  38. Weil YA, Qawasmi F, Liebergall M, Mosheiff R, Khoury A. Use of fully threaded cannulated screws decreases femoral neck shortening after fixation of femoral neck fractures. Arch Orthop Trauma Surg. 2018;138(5):661–7.

    PubMed  Google Scholar 

  39. Chen SY, Chang SM, Tuladhar R, Wei Z, Xiong WF, Hu SJ, et al. A new fluoroscopic view for evaluation of anteromedial cortex reduction quality during cephalomedullary nailing for intertrochanteric femur fractures: the 30 degrees oblique tangential projection. BMC Musculoskelet Disord. 2020;21(1):719.

    CAS  PubMed  PubMed Central  Google Scholar 

  40. Chang SM. The difference between AO and OTA on 31A2.3 fractures. Injury. 2016;47(6):1361.

    PubMed  Google Scholar 

  41. Cheung ZB, Selverian S, Barbera J, Forsh DA. The effect of nail diameter on proximal femoral shortening after internal fixation of pertrochanteric hip fractures with short cephalomedullary nails. J Orthop. 2020;22:358–61.

    PubMed  PubMed Central  Google Scholar 

  42. Ceynowa M, Zerdzicki K, Klosowski P, Pankowski R, Roclawski M, Mazurek T. The early failure of the gamma nail and the dynamic hip screw in femurs with a wide medullary canal. A biomechanical study of intertrochanteric fractures. Clin Biomech (Bristol, Avon). 2020;71:201–7.

    Google Scholar 

  43. Durusoy S, Paksoy AE, Korkmaz M, Daglar B, Elibol FKE. The effect of medullary fill on varus collapse in AO 31A3 intertrochanteric (reverse obliquity) fracture treated with cephalomedullary nails. Orthop Traumatol Surg Res. 2021;107:102804.

    PubMed  Google Scholar 

Download references

Acknowledgements

Not applicable.

Funding

The study was supported by funding from the National Nature Science Foundation of China (NSFC No. 81772323) and was financially sponsored by Prof. Chang.

Author information

Authors and Affiliations

  1. Department of Orthopaedic Surgery, Yangpu Hospital, School of Medicine, Tongji University, 450 Tengyue Road, Shanghai, 200090, China

    Hui Song, Shi-Min Chang, Sun-Jun Hu & Shou-Chao Du

Authors
  1. Hui Song
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Shi-Min Chang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Sun-Jun Hu
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Shou-Chao Du
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

SMC and HS proposed the study conception and design. HS and SCD performed the collection of the data. HS and SJH conducted the analysis and interpretation of the data. HS was the major contributor in writing the manuscript. All the authors read and approved the final manuscript.

Corresponding author

Correspondence to Shi-Min Chang.

Ethics declarations

Ethics approval and consent to participate

This study received ethical approval from the Institutional Review Committee of Yangpu Hospital, School of Medicine, Tongji University. Informed consent was obtained from all individual participants included in the study.

Consent for publication

The participants have consented to the publication of the article.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Song, H., Chang, SM., Hu, SJ. et al. Low filling ratio of the distal nail segment to the medullary canal is a risk factor for loss of anteromedial cortical support: a case control study. J Orthop Surg Res 17, 27 (2022). https://doi.org/10.1186/s13018-022-02921-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s13018-022-02921-z

Keywords

Journal of Orthopaedic Surgery and Research

ISSN: 1749-799X