Orthopedics

Feature Article 

The Effect of Configuration of Rhombic Cannulated Screws on Internal Fixation of Femoral Neck Fractures

Jialiang Guo, MD; Weichong Dong, MM; Yingchao Yin, MD; Ruipeng Zhang, MD; Zhiyong Hou, MD; Yingze Zhang, BS

Abstract

Femoral neck fractures are commonly encountered clinical problems, especially in patients with osteoporosis, and have high morbidity and mortality. Internal fixation of femoral neck fractures using 3 cannulated screws placed in an inverse triangle configuration is commonly performed. Recently, the use of 4 cannulated screws in a rhombic configuration has been proposed. The aim of this study was to investigate the outcomes of femoral neck fractures treated using either an inverse triangle or rhombic configuration to determine which had a better clinical prognosis. A total of 138 consecutive patients without any previous hip surgery who had femoral neck fractures treated with cannulated compression screws in either an inverse triangle or rhombic configuration were reviewed. Patients' demographic and radiological data were collected from the authors' institutional database. The authors found that the rhombic configuration did not have a better result in decreasing complications, such as femoral neck shortening or screw exit, or in Harris Hip Scores and other clinical prognoses compared with the inverse triangle configuration. In addition, the technique used for applying 4 screws (especially the posterior ones) needs to be improved, so until then, using 3 screws in an inverse triangle configuration remains the gold standard for the treatment of femoral neck fractures. [Orthopedics. 2020; 43(2):e72–e78.]

Abstract

Femoral neck fractures are commonly encountered clinical problems, especially in patients with osteoporosis, and have high morbidity and mortality. Internal fixation of femoral neck fractures using 3 cannulated screws placed in an inverse triangle configuration is commonly performed. Recently, the use of 4 cannulated screws in a rhombic configuration has been proposed. The aim of this study was to investigate the outcomes of femoral neck fractures treated using either an inverse triangle or rhombic configuration to determine which had a better clinical prognosis. A total of 138 consecutive patients without any previous hip surgery who had femoral neck fractures treated with cannulated compression screws in either an inverse triangle or rhombic configuration were reviewed. Patients' demographic and radiological data were collected from the authors' institutional database. The authors found that the rhombic configuration did not have a better result in decreasing complications, such as femoral neck shortening or screw exit, or in Harris Hip Scores and other clinical prognoses compared with the inverse triangle configuration. In addition, the technique used for applying 4 screws (especially the posterior ones) needs to be improved, so until then, using 3 screws in an inverse triangle configuration remains the gold standard for the treatment of femoral neck fractures. [Orthopedics. 2020; 43(2):e72–e78.]

Femoral neck fractures are commonly encountered among elderly patients, in whom these fractures are associated with high mortality and morbidity, as well as in young, fit individuals subjected to high-energy trauma.1,2 Nonunion and avascular necrosis are common complications and result in death and loss of labor capacity. To minimize negative results, it is essential to take active preventive measures and provide appropriate treatment. Current implant selections for femoral neck fractures remain a topic of considerable interest and vary substantially, depending on the extent of displacement, bone quality, fracture patterns, physiological age, and other related factors. Nonoperative management is only considered in patients with low demands in terms of prognosis.

Numerous surgical techniques are proposed for the treatment of femoral neck fractures.3 Some reports have claimed that the different strategies show little differences with outcomes.1,4 However, the implant type can have different effects. It was reported that the holding capability of cannulated screws was inferior compared with other screw types and may lead to complications, especially in patients with osteoporosis.5 Biplane double-supported screw fixation was recently introduced and exhibited increased fixation strength.6 However, in patients who are not fit for arthroplasty, 3 inverted parallel cannulated screws remain an effective treatment for femoral neck fractures.7,8 Through compression to the fracture site, it accomplishes anatomic reduction and rigid fixation and promotes fracture healing. The procedure is minimally invasive, and the rate of blood transfusion is low.9,10

A clear consensus has been reached that using 3 inverted parallel cannulated screws is more beneficial for preventing complications than other techniques. With superior torsional stability and limited disturbance to the femoral head blood supply, it is the most widely used method for the fixation of femoral neck fractures.

Recently, a rhombic configuration using 4 screws has been proposed; however, a comparison with the inverse triangle configuration was not made. The aim of the current study was to investigate the outcomes of femoral neck fractures treated using the inverse triangle vs the rhombic configuration to determine which is better in terms of clinical prognosis.

Materials and Methods

Patient Demographics

From 2015 to 2016, data were collected for 160 patients treated with cannulated screws in either an inverse triangle or rhombic configuration. Patients' demographic and radiological data were reviewed. Data review was conducted in 2018, and written informed consent was obtained from patients or their legal guardians.

Patients with a closed femoral neck fracture treated with cannulated compression screws and a follow-up time greater than 1 year were included. Patients with severe cognitive dysfunction, those with previous or pathological femoral neck fracture, and those treated with other internal fixations were excluded. Twenty-two patients were lost to follow-up. Among the other 138 patients, 105 were injured after slips, trips, or falls, and 33 patients were involved in traffic accidents. This study received ethics committee approval.

Patients were placed into either the inverse triangle group (n=77) or the rhombic group (n=61), depending on the configuration of the cannulated screws. Patients in the inverse triangle group (mean age, 52±9.4 years) were treated with 3 compression screws. Patients in the rhombic group (mean age, 54±9.0 years) were treated with 4 compression screws (Table 1). All surgeries were conducted by experienced surgeons. Mean delayed time to surgery was 3 days (range, 2–7 days), which was primarily due to time taken in reporting to the hospital or examining biochemical indices.

General Characteristics of the Patients in the Inverse Triangle and Rhombic Configuration Groups

Table 1:

General Characteristics of the Patients in the Inverse Triangle and Rhombic Configuration Groups

Surgical Procedures

All patients were maintained in bed until the operation. Surgery was performed under general anesthesia or regional anesthesia. Patients were placed in the supine position and were treated by percutaneous fixation with different configurations of 3 or 4 cannulated screws. The reduction was conducted using a traction table. For those with difficult restorations, 3-dimensional femoral head and shaft reduction techniques were applied. After reduction, a guide pin was inserted with a lateral entry point located at the median line of the lateral cortex. The guide pin was close to the femoral calcar and parallel to the neck shaft angle in the anteroposterior view. In the lateral view, the guide pin was parallel to the anteversion angle and inserted along the center of the femoral head and neck. Subsequently, the partial threaded cannulated screws (6.5 mm; Stryker, Kalamazoo, Michigan) were used and inserted. The reduction quality was ensured with an image intensifier. Stitches were removed at 2 weeks postoperatively, except for when delayed due to wound swelling.

Perioperative Management

Passive exercises were performed in hip joints postoperatively. Low- molecular–weight heparin was administered for 2 weeks to prevent deep venous thrombosis postoperatively. Patients were guided to sit on the bed and exercise their lower limb muscles for the first day. Starting on postoperative day 3, patients were encouraged to attempt partial weight-bearing ambulation with assistance. Full weight bearing was started from 20 kg at 4 to 6 weeks, with an incremental increase of 5 kg per week postoperatively.

Outcome Measurements

Patients were followed in the orthopedic clinic and then assessed to check the progress of union and possible complications every 2 or 3 months for up to at least 1 year. Data regarding incision size, surgical time (from opening to closing), surgical blood loss, and hospital length of stay were reviewed. Complications, including screw exit, femoral neck shortening, nonunion, cutout, and avascular necrosis, were recorded. Femoral neck shortening was categorized into 4 levels: degree 0; degree 1; degree 2; and degree 3.11,12 Hip functions were evaluated using the Harris Hip Score on a scale of 1 to 100, being categorized as excellent (90 to 100), good (80 to 89), fair (70 to 79), and poor (<69).13,14 Fractures that failed to exhibit progressive healing after 12 months were classified as nonunion. When there was disagreement on the assessment after evaluation by the first author (J.G.), the decision made by the corresponding author was used (Z.H.).

Statistical Analysis

Continuous variables were expressed as mean±SD. Frequencies were used to express categorical data. SPSS version 21.0 (IBM, Armonk, New York) was used to perform the statistical analysis. Statistical analysis between the 2 groups was completed using the nonparametric Mann–Whitney U test and Pearson chi-square test. Fisher's exact test was performed when more than 20% of the cells had an expected frequency of less than 5. The level of significance was set as P=.05 for all statistical tests.

Results

No significant differences in the classification of fractures were observed in the inverse triangle and rhombic groups (Table 1). No significant differences were found in the baseline characteristics between groups (Table 1). Mean follow-up time was 18 months (range, 12–21 months).

All operations were performed by a senior surgeon (Z.H.). Images of femoral neck fractures fixed with cannulated compression screws are shown in Figure 1. Although no significant differences were found in operative time, deep venous thrombosis, and hospital length of stay (P>.05), patients in the rhombic group had relatively short hospital stays (Table 2). No patients in either group had infections postoperatively. Significant differences were found in incision size, surgical blood loss, and fluoroscopic time, suggesting that additional screw insertion in the rhombic group wasted time and increased trauma.

Postoperative anteroposterior (A) and lateral (B) radiographs showing the screws placed in the inverse triangle configuration. Postoperative anteroposterior (C) and lateral (D) radiographs showing the screws placed in the rhombic configuration.

Figure 1:

Postoperative anteroposterior (A) and lateral (B) radiographs showing the screws placed in the inverse triangle configuration. Postoperative anteroposterior (C) and lateral (D) radiographs showing the screws placed in the rhombic configuration.

Clinical Outcomes of the Perioperative Period in the Inverse Triangle and Rhombic Configuration Groups

Table 2:

Clinical Outcomes of the Perioperative Period in the Inverse Triangle and Rhombic Configuration Groups

Regarding complications after follow-up, no significant differences were found in shortening, cutout, nonunion, or avascular necrosis (2.6% [inverse triangle group] vs 6.6% [rhombic group]) (Figures 24; Table 3). Fracture healing was observed in most patients in both groups. Furthermore, no significant differences were observed regarding screw exit between groups. At the end of follow-up, no statistically significant differences in hip functions were exhibited (Table 3). One patient in the inverse triangle group and 6 in the rhombic group were found to have 1 screw malinserted (in-out-in) and were examined by computed tomography scan; the differences were significant (Figure 5). Nevertheless, no serious complications were induced by malinsertion.

Preoperative anteroposterior radiograph (A), preoperative lateral radiograph (B), postoperative anteroposterior radiograph (C), postoperative lateral radiograph (D), anteroposterior radiograph before finishing follow-up (E), and anteroposterior radiograph before finishing follow-up (F) of a 55-year-old woman with a Garden type II fracture treated with 3 screws in an inverse triangle configuration.

Figure 2:

Preoperative anteroposterior radiograph (A), preoperative lateral radiograph (B), postoperative anteroposterior radiograph (C), postoperative lateral radiograph (D), anteroposterior radiograph before finishing follow-up (E), and anteroposterior radiograph before finishing follow-up (F) of a 55-year-old woman with a Garden type II fracture treated with 3 screws in an inverse triangle configuration.

Preoperative anteroposterior radiograph (A), preoperative lateral radiograph (B), postoperative anteroposterior radiograph (C), postoperative lateral radiograph (D), anteroposterior radiograph before finishing follow-up (E), and postoperative lateral radiograph before finishing follow-up (F) of a 59-year-old woman with a Garden type III fracture treated with 4 screws in a rhombic configuration.

Figure 3:

Preoperative anteroposterior radiograph (A), preoperative lateral radiograph (B), postoperative anteroposterior radiograph (C), postoperative lateral radiograph (D), anteroposterior radiograph before finishing follow-up (E), and postoperative lateral radiograph before finishing follow-up (F) of a 59-year-old woman with a Garden type III fracture treated with 4 screws in a rhombic configuration.

Preoperative anteroposterior radiograph (A), postoperative anteroposterior radiograph (B), postoperative lateral radiograph (C), anteroposterior radiograph at 1 month postoperatively (D), anteroposterior radiograph at 3 months postoperatively (E), anteroposterior radiograph at 9 months postoperatively (F), computed tomography scan at 9 months postoperatively (G), and anteroposterior radiograph before finishing follow-up (H) of a 42-year-old man with a Garden type III fracture treated with 4 screws in a rhombic configuration who experienced failure. The patient was re-treated with total arthroplasty at 12 months postoperatively, but subluxation occurred.

Figure 4:

Preoperative anteroposterior radiograph (A), postoperative anteroposterior radiograph (B), postoperative lateral radiograph (C), anteroposterior radiograph at 1 month postoperatively (D), anteroposterior radiograph at 3 months postoperatively (E), anteroposterior radiograph at 9 months postoperatively (F), computed tomography scan at 9 months postoperatively (G), and anteroposterior radiograph before finishing follow-up (H) of a 42-year-old man with a Garden type III fracture treated with 4 screws in a rhombic configuration who experienced failure. The patient was re-treated with total arthroplasty at 12 months postoperatively, but subluxation occurred.

Clinical Outcomes in the Inverse Triangle and Rhombic Configuration Groups

Table 3:

Clinical Outcomes in the Inverse Triangle and Rhombic Configuration Groups

Pre- and postoperative radiographs and computed tomography (CT) scans of a 56-year-old woman with a Garden type II fracture fixated using 4 screws in a rhombic configuration. Preoperative anteroposterior radiograph (A), lateral radiograph (B), and 3-dimensional CT reconstruction scan (C) showing the fracture. Postoperative anteroposterior radiograph (D), lateral radiograph (E), and 3-dimensional CT reconstruction scans (F–H) showing that the posterior screw perforated out (in-out-in) of the cortical femoral neck. Anteroposterior (I) and lateral (J) radiographs before finishing follow-up. No serious complications occurred after follow-up.

Figure 5:

Pre- and postoperative radiographs and computed tomography (CT) scans of a 56-year-old woman with a Garden type II fracture fixated using 4 screws in a rhombic configuration. Preoperative anteroposterior radiograph (A), lateral radiograph (B), and 3-dimensional CT reconstruction scan (C) showing the fracture. Postoperative anteroposterior radiograph (D), lateral radiograph (E), and 3-dimensional CT reconstruction scans (F–H) showing that the posterior screw perforated out (in-out-in) of the cortical femoral neck. Anteroposterior (I) and lateral (J) radiographs before finishing follow-up. No serious complications occurred after follow-up.

Discussion

Although various instruments have been used for the stabilization of femoral neck fractures, optimal treatment remains internal fixation and arthroplasty. Currently, there may be sufficient evidence to support using more arthroplasties in displaced femoral neck fractures; however, for patients younger than 65 years, the optimal treatment of acute femoral neck fracture remains internal fixation for patients with high functional demands.

This retrospective study of 138 patients compared 2 groups treated with cannulated screws. No significant differences were observed in terms of preventing shortening, screw exit, and nonunion in the treatment of femoral neck fractures. However, the perioperative data illustrated that patients in the rhombic group had longer incision size, longer fluoroscopic time, and more blood loss. To the authors' knowledge, this study is the first clinical study to collect operative data to compare 2 fixation methods (3 cannulated screws placed in an inverse triangle configuration or 4 cannulated screws placed in a rhombic configuration) in the treatment of femoral neck fractures. This study suggests that inverse fixation remains the first choice for treating femoral neck fractures.

Many other methods for fixation have been introduced. A 4-quadrant parallel peripheral screw fixation technique was used; it was similar to the inverse triangle configuration in that 2 distal screws were used but a proximal screw was added.15 The current authors do not believe that the mechanical characteristics in this method are better than those of the triangular ones. Biplane double- supported screw fixation was introduced and studies found that it improved fixation strength.6,16 However, managing the screws under the level of the small trochanter is challenging for less experienced surgeons. Multiple compressive screws have been advocated to treat Garden type I and II fractures.17,18 In addition to cannulated screws, a more stable fixation using dynamic hip screws with anti-rotational screws has also been advocated.19 However, extensive soft tissue stripping, longer hospital stays, and other complications are substantial problems, hindering its clinical use.7

The rhombic configuration is similar to the inverse triangle configuration in that it has 1 distal screw, but it also has an additional proximal screw. Because of increased contact with bones, this configuration provides better initial stability and controls collapse; the 4 screws placed in the periphery of the femoral neck act as supporting pillars and provide excellent stability. The short learning curve and low expenditures are also advantages of the 4-screw rhombic configuration.

Nevertheless, other problems should be solved before using the rhombic configuration. Using more screws means removing more bone, which may result in the area of bone union decreasing and could lead to nonunion. The balance between bone removal and the number of screws inserted is controversial. In the current study, fluoroscopic time, incision size, and surgical blood loss were significantly greater in the rhombic group. Although there were no significant differences in terms of operation time, the increased time was substantial in the rhombic group. Interestingly, hospital stays were shorter in the rhombic group than in the inverse triangle group. This finding may be explained by the fact that 4-screw fixations increase the confidence of surgeons because they increase stability. Furthermore, avascular necrosis remains one of the greatest concerns in femoral neck fractures. The occurrence of avascular necrosis was not decreased in the rhombic group, and complications of Garden type III or IV fractures remained high.

Stable internal fixation and anatomic reduction are essential in treating femoral neck fractures. When the fracture occurs, the prognosis of femoral neck fracture is determined; therefore, the prognosis is not better when more screws are inserted. In the authors' opinion, if 3 screws are sufficient to provide stability and bone union for a femoral neck fracture, then 4 screws are not necessary, especially for patients who are poor, as screws are expensive.

With 3 screws, all of the screws are placed in the periphery of the femoral neck. When 4 screws are inserted, the middle 2 screws may have less contact with the femoral neck, leaving more space to insert the proximal screw. Although the supporting strength may be improved due to 1 additional screw in the rhombic configuration, the convergence of screws to the center may result in average strength decreasing (especially the middle 2 screws), leading to displacement and instability postoperatively. With 4 screws, the preferred position may not be realized.

According to a study of proximal femur morphology, Nakanishi et al20 found the definite screw positions for multiple screw fixation in femoral neck fractures and reported that the mean neck canal height was 22 mm. Therefore, there is limited space left for the proximal screw and it is possible to insert cannulated screws in nonideal positions that could result in less compression force acting on the fracture lines.

In the current study, some patients were found to have cannulated screws located posteriorly, perforating out of the cortex of the femoral neck, and the proximal screws were all in place (Figure 5). This happened because the posterior wall of the femoral neck is nearly vertical and adjacent to the femoral axis. Due to limited space provided by the femoral neck, screws that perforate out of the cortex may be observed and could be defined as iatrogenic injuries, especially in patients with more screws malinserted in the rhombic group. Fortunately, there were no serious complications caused by incorrect insertion. Although it was rare in the inverse triangle group and no significant differences were observed between groups, the differences may be more obvious when the number of patients increases. This suggests that 3 cannulated screws are safer than 4 in treating femoral neck fractures, especially in patients with narrow femoral neck canals.

According to the Garden classification, more complicated displaced fractures (Garden type III or IV) are treated using the 4-screw rhombic configuration. However, no significant differences were observed in the classification of femoral neck fractures in the inverse triangle or rhombic groups.

Other factors also affected the results in this study. Mean time between injury and surgical intervention was 3 days, and this delay may have affected the surgical results, especially the rate of avascular necrosis. It has been reported that a “linking” of the femoral vessels through prompt reduction results in decreased intracapsular decompression, restoration of blood flow to the femoral head, and a minimization of the risk of necrosis.19,21 Therefore, the unavoidable delay in time between injury and surgical intervention may increase the rate of avascular necrosis.

However, several studies reported no differences in the rate of avascular necrosis with delays of more than 24 hours, even more than 1 week. In a long-term follow-up of 1503 fractures, Barnes et al22 described no significant differences in necrosis if the operation was delayed up to 1 week. Patients are often frail and admitted with abnormal blood pressure, cardiac or renal abnormalities, and cognitive disorders. Preoperative examinations and nursing care for patients with specific factors, such as cardiac failure, dementia, or bronchopneumonia, are necessary to decrease the rates of mortality perioperatively.22 Kenzora et al23 found a decrease in the mortality rate through delaying operation from within 24 hours of admission to between 2 and 5 days from 34% to 5.8%.24 Early intervention for the fracture is necessary as long as the patient's condition permits.23 The rate of avascular necrosis was also related to the type of fixation.25,26 Above all, the results exhibited in the current study remain objective; more evidence supports the notion that inverse triangle configurations are sufficient to treat femoral neck fractures.

A limitation of this study included the potential user bias because surgeons could not be blinded regarding the configuration used in the treatment. In addition, different surgeons had varying degrees of expertise in operative skills. The follow-up time in this trial was limited, and there was no long-term follow-up, which would be more illustrative. The short follow-up time may be insufficient to register all cases of avascular necrosis. Nevertheless, an average follow-up period of 12 months remains sufficient to demonstrate the occurrence of bone union or most postoperative complications.

Conclusion

The authors found that the inverse triangle configuration and rhombic configuration are comparable in terms of complications and prognosis in the treatment of femoral neck fractures. However, the expertise in applying 4 screws in the rhombic configuration needs to be improved. Therefore, until that occurs, using 3 screws with an inverse triangle configuration remains the gold standard for the treatment of femoral neck fractures.

References

  1. Broderick JM, Bruce-Brand R, Stanley E, Mulhall KJ. Osteoporotic hip fractures: the burden of fixation failure. Scientific World Journal. 2013;2013:515197. https://doi.org/10.1155/2013/515197 PMID: doi:10.1155/2013/515197 [CrossRef]23476139
  2. Wilk R, Skrzypek M, Kowalska M, et al. Standardized incidence and trend of osteoporotic hip fracture in Polish women and men: a nine year observation. Maturitas. 2014;77(1):59–63. https://doi.org/10.1016/j.maturitas.2013.09.004 PMID: doi:10.1016/j.maturitas.2013.09.004 [CrossRef]
  3. Estrada LS, Volgas DA, Stannard JP, Alonso JE. Fixation failure in femoral neck fractures. Clin Orthop Relat Res. 2002;399:110–118. https://doi.org/10.1097/00003086-200206000-00013 PMID: doi:10.1097/00003086-200206000-00013 [CrossRef]
  4. Miller BJ, Lu X, Cram P. The trends in treatment of femoral neck fractures in the Medicare population from 1991 to 2008. J Bone Joint Surg Am. 2013;18;95:e132. doi:10.2106/JBJS.L.01163 [CrossRef]24048563
  5. Parker MJ. Results of internal fixation of Pauwels type-3 vertical femoral neck fractures. J Bone Joint Surg Am. 2009;91(2):490–491. PMID:19182004
  6. Filipov O, Gueorguiev B. Unique stability of femoral neck fractures treated with the novel biplane double-supported screw fixation method: a biomechanical cadaver study. Injury. 2015;46(2):218–226. https://doi.org/10.1016/j.injury.2014.11.013 PMID: doi:10.1016/j.injury.2014.11.013 [CrossRef]
  7. Haidukewych GJ, Rothwell WS, Jacofsky DJ, Torchia ME, Berry DJ. Operative treatment of femoral neck fractures in patients between the ages of fifteen and fifty years. J Bone Joint Surg Am. 2004;86(8):1711–1716. https://doi.org/10.2106/00004623-200408000-00015 PMID: doi:10.2106/00004623-200408000-00015 [CrossRef]15292419
  8. Kauffman JI, Simon JA, Kummer FJ, Pearlman CJ, Zuckerman JD, Koval KJ. Internal fixation of femoral neck fractures with posterior comminution: a biomechanical study. J Orthop Trauma. 1999;13(3):155–159. https://doi.org/10.1097/00005131-199903000-00001 PMID: doi:10.1097/00005131-199903000-00001 [CrossRef]10206245
  9. Blomfeldt R, Törnkvist H, Ponzer S, Söderqvist A, Tidermark J. Internal fixation versus hemiarthroplasty for displaced fractures of the femoral neck in elderly patients with severe cognitive impairment. J Bone Joint Surg Br. 2005;87(4):523–529. https://doi.org/10.1302/0301-620X.87B4.15764 PMID: doi:10.1302/0301-620X.87B4.15764 [CrossRef]15795204
  10. Yih-Shiunn L, Chien-Rae H, Wen-Yun L. Surgical treatment of undisplaced femoral neck fractures in the elderly. Int Orthop. 2007;31(5):677–682. https://doi.org/10.1007/s00264-006-0243-3 PMID: doi:10.1007/s00264-006-0243-3 [CrossRef]
  11. Boraiah S, Paul O, Hammoud S, Gardner MJ, Helfet DL, Lorich DG. Predictable healing of femoral neck fractures treated with intra-operative compression and length-stable implants. J Trauma. 2010;69(1):142–147. https://doi.org/10.1097/TA.0b013e3181bba236 PMID: doi:10.1097/TA.0b013e3181bba236 [CrossRef]
  12. Zlowodzki M, Jönsson A, Paulke R, Kregor PJ, Bhandari M. Shortening after femoral neck fracture fixation: is there a solution?Clin Orthop Relat Res.2007;461 (461):213–218. https://doi.org/10.1097/BLO.0b013e31805b7ec4 PMID:17415006
  13. Harris WH. Traumatic arthritis of the hip after dislocation and acetabular fractures: treatment by mold arthroplasty. An end-result study using a new method of result evaluation. J Bone Joint Surg Am. 1969;51(4):737–755. https://doi.org/10.2106/00004623-196951040-00012 PMID: doi:10.2106/00004623-196951040-00012 [CrossRef]5783851
  14. Marchetti P, Binazzi R, Vaccari V, et al. Long-term results with cementless Fitek (or Fitmore) cups. J Arthroplasty. 2005;20(6):730–737. https://doi.org/10.1016/j.arth.2004.11.019 PMID: doi:10.1016/j.arth.2004.11.019 [CrossRef]16139709
  15. Satish BR, Ranganadham AV, Ramalingam K, Tripathy SK. Four quadrant parallel peripheral screw fixation for displaced femoral neck fractures in elderly patients. Indian J Orthop.2013;47(2):174–181. doi:10.4103/0019-5413.108912 [CrossRef]23682180
  16. Filipov O, Stoffel K, Gueorguiev B, Sommer C. Femoral neck fracture osteosynthesis by the biplane double-supported screw fixation method (BDSF) reduces the risk of fixation failure: clinical outcomes in 207 patients. Arch Orthop Trauma Surg. 2017;137(6):779–788. https://doi.org/10.1007/s00402-017-2689-8 PMID: doi:10.1007/s00402-017-2689-8 [CrossRef]28391429
  17. Hoskinson S, Morison Z, Shahrokhi S, Schemitsch EH. Managing AVN following internal fixation: treatment options and clinical results. Injury. 2015;46(3):497–506. https://doi.org/10.1016/j.injury.2014.11.016 PMID: doi:10.1016/j.injury.2014.11.016 [CrossRef]
  18. Panteli M, Rodham P, Giannoudis PV. Biomechanical rationale for implant choices in femoral neck fracture fixation in the non-elderly. Injury. 2015;46(3):445–452. https://doi.org/10.1016/j.injury.2014.12.031 PMID: doi:10.1016/j.injury.2014.12.031 [CrossRef]25597514
  19. Schwartsmann CR, Lammerhirt HM, Spinelli LF, Ungaretti Neto ADS. Treatment of displaced femoral neck fractures in young patients with DHS and its association to osteonecrosis. Rev Bras Ortop. 2017;53(1):82–87. https://doi.org/10.1016/j.rboe.2017.03.003 PMID: doi:10.1016/j.rbo.2017.01.007 [CrossRef]
  20. Nakanishi Y, Hiranaka T, Shirahama M, et al. Ideal screw positions for multiple screw fixation in femoral neck fractures: study of proximal femur morphology in a Japanese population. J Orthop Sci. 2018;23(3):521–524. https://doi.org/10.1016/j.jos.2018.01.012 PMID: doi:10.1016/j.jos.2018.01.012 [CrossRef]29459082
  21. Schwartsmann CR, Jacobus LS, Spinelli LF, et al. Dynamic hip screw for the treatment of femoral neck fractures: a prospective study with 96 patients. ISRN Orthop. 2014;2014:257871. https://doi.org/10.1155/2014/257871 PMID: doi:10.1155/2014/257871 [CrossRef]24967124
  22. Barnes R, Brown JT, Garden RS, Nicoll EA. Subcapital fractures of the femur: a prospective review. J Bone Joint Surg Br. 1976;58(1):2–24. https://doi.org/10.1302/0301-620X.58B1.1270491 PMID: doi:10.1302/0301-620X.58B1.1270491 [CrossRef]1270491
  23. Lewis PM, Waddell JP. When is the ideal time to operate on a patient with a fracture of the hip? A review of the available literature. Bone Joint J. 2016;98-B(12):1573–1581. https://doi.org/10.1302/0301-620X.98B12.BJJ-2016-0362.R2 PMID: doi:10.1302/0301-620X.98B12.BJJ-2016-0362.R2 [CrossRef]27909117
  24. Kenzora JE, McCarthy RE, Lowell JD, Sledge CB. Hip fracture mortality: relation to age, treatment, preoperative illness, time of surgery, and complications. Clin Orthop Relat Res. 1984;(186):45–56. PMID:6723159
  25. Razik F, Alexopoulos AS, El-Osta B, et al. Time to internal fixation of femoral neck fractures in patients under sixty years: does this matter in the development of osteonecrosis of femoral head?Int Orthop.2012;36(10):2127–2132. https://doi.org/10.1007/s00264-012-1619-1 PMID: doi:10.1007/s00264-012-1619-1 [CrossRef]22829122
  26. Guo J, Dong W, Yin B, et al. Intramedullary nails with cannulated screw fixation for the treatment of unstable femoral neck fractures. J Int Med Res. 2019;47(2):557–568. doi:10.1177/0300060518816185 [CrossRef]

General Characteristics of the Patients in the Inverse Triangle and Rhombic Configuration Groups

CharacteristicInverse Triangle Group (n=77)Rhombic Group (n=61)P
Male/female, No.40/3730/31.736
Age, mean±SD, y52±9.454±9.0.076
Garden classification, No..539
  Type I00
  Type II3726
  Type III2821
  Type IV1214

Clinical Outcomes of the Perioperative Period in the Inverse Triangle and Rhombic Configuration Groups

OutcomeInverse Triangle Group (n=77)Rhombic Group (n=61)P
Incision size, mean±SD, cm5.95±0.798.1±0.83<.001
Surgical blood loss, mean±SD, mL103±12.3109±10.9.002
Surgical time, mean±SD, min80.0±14.385.7±9.0.079
Fluoroscopy time, mean±SD, min20±3.530±5<.001
Infection, No.00
Deep venous thrombosis (No.)6.5% (5)11.5% (7).302
Hospital stay, mean±SD, d16.9±3.216.8±2.4.058

Clinical Outcomes in the Inverse Triangle and Rhombic Configuration Groups

OutcomeInverse Triangle Group (n=77)Rhombic Group (n=61)P
Patients with malinsertion, No. (%)1 (1.30)6 (4.90).044
Shortening ≥10 mm, No. (%)7 (9.1)6 (9.80).882
Screw exit, No. (%)15 (19.5)12 (21.3).791
Cutout, No. (%)01 (1.6).442
Nonunion, No. (%)6 (7.8)4 (6.6).781
Avascular necrosis, No. (%)6 (7.8)4 (6.6).781
Harris Hip Score, mean±SD85.7±3.186.1±3.4.204
Authors

The authors are from the Department of Orthopaedic Surgery (JG, YY, RZ, ZH, YZ), the Third Hospital of Hebei Medical University, Shijiazhuang; Key Laboratory of Orthopaedic Biomechanics of Hebei Province (JG, YY, RZ, ZH, YZ), Shijiazhuang; the Orthopaedic Research Institution of Hebei Province (JG, YY, RZ, YZ), Hebei; the Chinese Academy of Engineering (YZ), Beijing; and the Department of Pharmacy (WD), the Second Hospital of Hebei Medical University, Shijiazhuang, China.

Drs Guo and Dong contributed equally to this work and should be considered as equal first authors.

The authors have no relevant financial relationships to disclose.

This research was supported by the National Nature Science Foundation of China (grant number 81572162) and the Key Project of Medical Science Research in Hebei Province (grant number 20180451).

Correspondence should be addressed to: Zhiyong Hou, MD, Department of Orthopaedic Surgery, the Third Hospital of Hebei Medical University, Ziqiang Rd 139, Shijiazhuang, 050051 China ( 460706223@qq.com).

Received: August 14, 2018
Accepted: January 08, 2019
Posted Online: December 16, 2019

10.3928/01477447-20191212-03

Sign up to receive

Journal E-contents