Orthopedic Surgery Resident Exposure to Sliding Hip Screw Fixation for Intertrochanteric Femur Fractures: A Multicenter Study

Abstract

Background

This study aimed to determine the level of exposure to sliding hip screws amongst orthopedic surgery residents compared to intramedullary nail fixation for intertrochanteric femur fractures.

Methods

Data was collected from five orthopedic surgery residency programs through the case log system of the accreditation council for graduate medical education (ACGME) based on current procedural terminology codes (CPT). The rates of IMN for treatment of IT fracture (27245) were compared to SHS fixation (27244) for the period of 2017-2021. The location of the procedure was also logged as either a level one trauma center, non-trauma hospitals, and a veteran’s affairs hospital (VA). Rates of SHS usage were compared by year and location type using multivariate logistic binary regression.

Results

5,910 IT femur fractures were treated by orthopedic residents during the time period. IMN was utilized for 88.8% of cases. The highest usage of SHS was 15.6% in 2017 with a statistically significant decrease to 9.2% in 2021 (p < 0.001). SHS utilization was lowest at non-trauma centers (5.4%) and highest at level one trauma centers (11.7%).

Conclusion

Residents get limited experience with SHS compared to IMN in their training programs, and there is a significant trend toward fewer SHS implants being used by residents over the past 5 years. Residents’ limited experience with SHS during residency may contribute for the trend toward IMN use. Surgeons at academic institutions ought to recognize this trend and strongly consider their implant choice when treating intertrochanteric femur fractures for fear of sliding hip screws becoming a lost art.

Level of Evidence: IV

Introduction

Intertrochanteric (IT) femur fractures are one of the most common injuries treated by orthopedic surgeons and account for an annual incidence of roughly 150,000 injuries.^1,2 Given the increasing elderly population of the United States, the rate of osteoporosis is expected to increase along with the rates of osteoporotic fragility fractures such as intertrochanteric femur fractures.^3,4 Due to the significant impact on patient mobility, surgery is most commonly indicated in those patients that are medically stable in order to decrease mortality and to limit the morbidity associated with bedbound patients, which includes pneumonia, deep vein thrombosis and pressure sores.^5-7 The mainstays of operative treatment remain intramedullary nail (IMN) or sliding hip screw (SHS) fixation, where the choice of implant often seems based on surgeon preference.⁵ Prior studies comparing outcomes between the two treatment modalities have failed to demonstrate a significant difference with regard to outcomes, union rates or complication profiles.^8-11 That said, because of the internal buttress effect of the IMN, this implant is often indicated in the treatment of unstable intertrochanteric fractures, characterized by reverse obliquity orientation, subtrochanteric extension or posteromedial comminution.^12,13

Despite the lack of evidence demonstrating superiority of one implant over the other, there has been an evolving trend toward the preference of IMN over SHS for treatment of intertrochanteric femur fractures. Several studies have investigated Medicare, Veteran’s Affairs, and ABOS part II databases with demonstration of an increase in the use of IMN for IT fractures from 3% in 1999 to 92.4% in 2017.^14-17 Several explanations have been proposed for why such a drastic trend exists, to include lack of exposure to SHS in orthopedic surgery training.^18,19 However, the data to demonstrate that orthopedic surgery residents are lacking operative experience with SHS have not been reported. Thus, the purpose of this study was to investigate if a similar trend toward IMN exists within U.S. orthopedic surgery training programs. The authors of this study hypothesized that a parallel trend exists, with residents gaining limited experience using SHS compared to IMN for intertrochanteric femur fractures.

Methods

After review by institutional review board, this study was deemed exempt from full review. Data were then collected from five orthopedic surgery residency programs through the case log system of the accreditation council for graduate medical education (ACGME). These programs had a complement of 4, 5, 6, 8 and 8 residents annually for a total of 155 residents recording cases during the study period. Cases logged using current procedural terminology codes (CPT) 27244 and 27245 representing treatment of intertrochanteric femur fractures with plate/ screw construct and intramedullary nail implant respectively were included in review and collected for the five year span from 2017-2021. No patient specific information nor trainee identifiable information was available through this database. In addition to code type, the location of the performed procedure was recorded. The location was described as an academic level one trauma center, a non-trauma designated community hospital, or veteran’s affairs (VA) hospital. Each program rotated through a minimum of 1 level-one trauma center, 4 programs rotated through a non-trauma designated community hospital, and 4 programs rotated through a VA hospital.

Statistical analysis was performed using statistical package for social sciences (SPSS) (Version 24; IBM SPSS). Comparisons between SHS and IMN were made for both time over the five-year period from 2017 to 2021 and based on hospital type using multivariate logistic binary regression. 2017 was used as the reference value for the time comparison while the non trauma, community hospitals were used as the reference value for the hospital type comparison. Statistical significance was set to a p-value of < 0.5 and odds ratios were reported for each year and hospital location with respect to the reference.

Results

Between the years 2017 and 2021, resident physicians at the 5 included programs recorded the treatment of 5,910 intertrochanteric hip fractures. Overall, SHS was utilized in 659 (11.2%) cases while IMN was utilized in 5251 (88.8%) of cases. The highest rate of SHS usage was recorded in 2017 with a rate of 15.6%. The rate of SHS use dropped to 12.9% in 2018, 10.4 % in 2019 and 8.7% in 2020. In 2021, SHS were utilized in 9.2% of IT fractures. The rates from 2019-2021 were significantly decreased compared to the reference rate in 2017 (p < 0.001). Table 1 further demonstrates the rates of SHS usage from all years included. (Table 1)

Table 1.

Proportion of Sliding Hip Screw and Intramedullary Nail by Year

	Year	Total Cases	Sliding Hip Screw (27244)	Intramedullary Nail (27245)	P-Value	Odds Ratio [95% CI]
2017		1091	170 (15.6%)	921 (84.4%)	-	-
2018		1018	131 (12.9%)	887 (87.1%)	0.087	0.807 [0.63, 1.03]
2019		1192	124 (10.4%)	1068 (89.6%)	< 0.001	0.639 [0.50, 0.82]
2020		1201	104 (8.7%)	1097 (91.3%)	< 0.001	0.528 [0.41, 0.68]
2021		1408	130 (9.2%)	1278 (90.8%)	< 0.001	0.560 [0.44, 0.72]
Total		5910	659 (11.2%)	5251 (88.8%)	-	-

Statistical significance is shown with respect to 2017 as the reference value. P < 0.050 is considered significant, values are highlighted in bold.

With regard to hospital type, 391 procedures were recorded at non trauma centers, 260 at VA hospitals and 5,263 at level-one trauma centers. SHS usage was lowest at the non-trauma hospitals with a rate of 5.4%. SHS were utilized at a significantly higher rate in both VA hospitals (9.6%; p = 0.041). and at level one trauma centers (11.7%; p < 0.001) when compared to non-trauma hospitals. Table 2 further outlines the rate of different implant usage by location of treatment. (Table 2)

Table 2.

Proportion of Sliding Hip Screw and Intramedullary Nail by Hospital Type

Hospital Type	Total Cases	Sliding Hip Screw (27244)	Intramedullary Nail (27245)	P-Value	Odds Ratio [95% CI]
A)	391	21 (5.4%)	370 (94.6%)	-	-
B)	260	25 (9.6%)	235 (90.4%)	0.041	1.874 [1.03, 3.43]
C)	5259	613 (11.7%)	4646 (88.3%)	< 0.001	2.33 [1.49, 3.64]
Total	5910	659 (11.2%)	5251 (88.8%)	-	-

A) Community non-trauma hospital; B) Veteran’s Affair’s Hospital Systems; C) Level 1 trauma center. Statistical significance is shown with respect to a community non-trauma hospital as the reference value. P < 0.050 is considered significant, values are highlighted in bold.

Discussion

Intertrochanteric femur fractures are frequently encountered by orthopedic surgeons and are expected to grow in frequency given the aging population and increased rates of osteoporosis in the United States.^1,3,20 Treatment of IT fractures with a sliding hip screw or intramedullary nail often depends on surgeon preference, as no studies have demonstrated superiority of one implant over the other.^8-11 Recent literature has demonstrated a significant trend toward increased IMN usage, with suggestions that the trend may be in part due to surgeon experience during surgical training.^15,18,19 The results of this study confirm the suggestions that orthopedic surgical residents are getting less exposure to SHS fixation during their residency training, which may contribute to the trend seen.

The trend toward use of IMN for IT fractures was first noted by review of the American Board of Orthopedic Surgeons (ABOS) part 2 examination database in 2008 by Anglen et al. and later confirmed by Smith et al. in 2021.^15,16 This trend seemed to suggest that younger surgeons favored IMN over SHS. Further study of the Medicare beneficiary database by Forte et al. demonstrated preference for use of IMN was associated with younger age of the surgeon and teaching hospital status. They further suggested that rates of IMN fixation would increase as surgeons continue to have less exposure to SHS through residency training.²¹ Through use of questionnaires of current practicing orthopedic surgeons, Murray et al. and Mellema et al. similarly demonstrated that preference for IMN over SHS was associated with less surgeon experience as well as exposure during residency.^18,19 The present study’s further affirms these prior investigations. The present study, however, highlights changes that are fundamental beyond practice trends: without the appropriate training of residents now, we may not be able to safely affect practice patterns, even if desired, for decades. The orthopedic residents included in this study demonstrated limited exposure to SHS fixation for intertrochanteric fractures with a trend of overall rates of SHS use declining over the course of the included study period.

The current study also found that residents were more likely to encounter the use of SHS at level one trauma centers as opposed to a non trauma center. These findings seem to agree with a prior study by Niu et al., who performed a web based survey of members of the American Academy of Orthopedic Surgeons. Through this, the investigators demonstrated that staff surgeons were more likely to utilize SHS if they worked at an academic hospital, were traumatology trained or supervised residents. These surveys also demonstrated that familiarity with technique was frequently cited as the reason for the choice of implant used.²² Although it seems promising to resident education that surgeons who train residents are more likely to use a combination of SHS and IMN, the current study demonstrates orthopedic residents are encountering SHS use at a significantly decreasing rate.

Although outcomes following the use of IMN for IT fractures have demonstrated high union rates with low complication rates,^23,24 this trend toward IMN is not without consequence. The financial impact of this trend is particularly alarming as several studies have demonstrated a stark increase in cost associated with the use of IMN over SHS. Casnovsky et al. retrospectively reviewed all intertrochanteric fractures at their institution over a 5-year period and estimated cost of care with a time-driven activity-based costing. They found the average cost of care for patients undergoing treatment with SHS was significantly lower than those treated with both long and short IMN ($17,077 versus $19,314 and $21,372).²⁵ In a similar fashion, Swart et al. evaluated the cost effectiveness of each implant type based on fracture stability and implant failure rates. This study demonstrated SHS remained more cost effective for all IT femur fractures aside from those with reverse obliquity.²⁶ Despite this evidence for improved cost effectiveness, it may be that many orthopedic surgeons do not consider cost when making their implant decision. Interestingly, a previous study by McCarthy demonstrated that orthopedic surgeons accurately identified the price of implant in only 21% of cases.²⁷ Regardless of the reason, financial considerations for implant use ought to be considered, particularly when no clinical difference in outcomes is overwhelmingly evident.

In addition to cost, it is important to recognize that SHS is not only an appropriate treatment strategy for IT fractures but is also an important implant for the treatment of young patients with femoral neck fractures.²⁸ In fact, several studies have demonstrated lower failure rates among young patients with femoral neck fractures treated with SHS compared to cannulated screws.^29,30 Needless to say, the SHS remains an integral implant in the orthopedic surgeon’s toolbox. Exposure to this implant during residency is of critical importance to the resident’s ability to utilize it in future practice. The lack of exposure to SHS for the treatment of IT fractures could lead to limited comfort with the implant for treatment of femoral neck fractures as well.

This study has multiple limitations. First, the information gathered through the ACGME case log is dependent on accurate reporting of procedures by the residents involved. For this reason, the system is subject to over or under reporting as well as scenarios that involve multiple residents recording the same procedure. Secondly, the case logs do not include information on fracture pattern or stability, which is a critical factor in determining the appropriate implant. Finally, the results of this study represent the experiences of a small sample group of residents at 5 residency programs out of 210 in the United States. Thus, this limited study may not be applicable to all orthopedic surgery residents.

Conclusion

This is the first study to our knowledge to evaluate orthopedic surgery residents’ experience using sliding hip screws versus intramedullary nails for the treatment of intertrochanteric femur fractures. Residents get a much more limited experience with SHS than they do IMN in their training programs, and there is a significant trend toward fewer SHS implants being used by residents over the past 5 years. Thus, the limited experience orthopaedic surgery residents have with SHS during residency may account for the increased trend toward IMN use that has been shown throughout the field of orthopedic surgery. Surgeons at academic institutions ought to recognize this trend and strongly consider their implant choice when treating intertrochanteric femur fractures for fear of sliding hip screws becoming a lost art.