Proximal femoral nail anti‐rotation vs dynamic hip screws decrease the incidence of surgical site infections in patients with intertrochanteric fractures: A meta‐analysis

Abstract

In this study, a meta‐analysis was conducted to comprehensively analyse the effectiveness of using proximal femoral nail anti‐rotation (PFNA) and dynamic hip screws (DHS) to treat intertrochanteric fractures on postoperative surgical site infections (SSI). PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from their inception until December 2022 to identify studies that compared PFNA and DHS in the treatment of intertrochanteric fractures. Two investigators independently screened the retrieved studies to assess their quality and verify their eligibility for inclusion. Meta‐analyses were performed with RevMan 5.4 software. Thirty studies, including 3158 patients, met the inclusion criteria. These studies included 1574 patients treated with PFNA, and 1584 were treated with DHS. The findings of the meta‐analysis revealed a significant reduction in the incidence of SSI in patients treated with PFNA compared with those treated with DHS (2.64% vs 6.76%, odds ratio [OR]: 0.40, 95% confidence intervals [CIs]: 0.28–0.57, P < .001), superficial SSI (2.58% vs 5.01%, OR: 0.53, 95% CIs: 0.33–0.85, P = .008) and deep SSI (1.26% vs 3.43%, OR: 0.41, 95% CIs: 0.19–0.92, P = .03). PFNA was more effective than DHS in reducing the incidence of SSI. Even so, significant variations in sample sizes among the included studies meant that the methodology for some studies had qualitative deficiencies. Therefore, additional studies with large sample sizes are needed to validate these results.

1. INTRODUCTION

Intertrochanteric fractures are localised to the space between the greater and lesser trochanters of the femur. These are common proximal femur fractures, with a preponderance in postmenopausal women. ¹ , ² , ³ the number of hip fractures worldwide will reportedly increase from 1.26 million in 1990 to 2.6 million in 2025 and 4.5 million in 2050. ⁴ Intertrochanteric fractures account for approximately 50% of all hip fractures. ⁵ These fractures usually result from high‐energy external forces, including falls, motor vehicle accidents, and sports injuries. ⁶ As the population ages and bodily functions decline, these fractures become more prominent in adults over 45 who are prone to osteoporosis from derangements in calcium homeostasis, including decreased intake and reduced absorption. These factors increase the yearly incidence of intertrochanteric fractures. In contrast, factors related to greater functional recovery that reduce the incidence of complications from intertrochanteric fractures include early repositioning and effective fracture fixation. ⁷

Currently, extramedullary and intramedullary fixations are commonly used to treat intertrochanteric fractures in clinical practice. The dynamic hip screw (DHS) is a classic example of extramedullary fixation. DHS insertion involves passing a nail through the femoral bone and into the medullary cavity. One end of the nail holds the bone fragments in place and ensures that they resume their original positions. ⁸ , ⁹ Directional pressure is then applied to the fracture site via the other end of the nail. This promotes bone healing and reconstruction. In contrast, inserting a proximal femoral nail anti‐rotation (PFNA) device involves driving a nail from the femoral trochanter through the marrow cavity to the fracture site. In so doing, the bone fragments at the fracture site are fixed to the nail. ¹⁰ Unlike DHS, the PFNA device has a barb on the nail that prevents the nail from rotating within the medullary cavity. This feature increases the effectiveness of PFNA. Many clinical reports have been published on treating intertrochanteric fractures with the aforementioned surgical procedures. However, few studies have evaluated the effectiveness of these procedures in postoperative incisional infections to treat intertrochanteric fractures. Therefore, this study aimed to investigate the efficacy of PFNA and DHS on surgical site infections (SSI) in the treatment of intertrochanteric fractures. The authors postulate that the findings of this meta‐analysis will provide an evidence‐based medical approach for selecting the best surgical option in clinical practice.

2. MATERIALS AND METHODS

2.1. Literature search

The PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from their inception until December 2022 for studies comparing PFNA and DHS in the treatment of intertrochanteric fractures. The following subject terms, combined with free words, were used to conduct the search: (1) intertrochanteric fractures; (2) proximal femoral nail anti‐rotation, PFNA; and (3) dynamic hip screw, DHS. Studies were manually retrieved from the databases to assess their quality and eligibility for inclusion.

2.2. Inclusion and exclusion criteria

The inclusion criteria were: (1) studies with a definite diagnosis of intertrochanteric fractures; (2) studies comparing PFNA and DHS in the treatment of intertrochanteric fractures; and (3) outcome indicators for SSI, superficial SSI, and deep SSI. The exclusion criteria were: (1) studies without intertrochanteric fractures; (2) studies that did not compare PFNA with DHS; (3) studies with unavailable manuscripts; (4) studies from conferences, abstracts, reviews, or case reports; and (5) duplicate publications.

2.3. Data extraction and quality assessment

All retrieved studies were screened independently by two authors according to the inclusion and exclusion criteria. Disagreements were resolved through a third investigator. The extracted data included the authors, publication year, patient sample size, sex, age, and outcome indicators. Literature quality was evaluated using the modified Jadad method. This method evaluated the generation of random sequences, randomization concealment, blinding, as well as withdrawal and exit. Studies could be assigned a total score of 7. However, scores between 0 and 3 indicated low‐quality literature, while scores between 4 and 7 indicated high‐quality literature.

2.4. Statistical analysis

The meta‐analysis was performed using RevMan 5.4 software. Extracted data involving dichotomous variables were described using odds ratios (OR) and 95% confidence intervals (CIs). In contrast, extracted data involving continuous variables was described by mean differences (MD) and 95% CIs. The χ ² test was used to evaluate heterogeneity among studies. If P > .1 or I ² < 50% indicated good homogeneity among studies, the fixed‐effects model was used for meta‐analysis; otherwise, the random‐effects model was used for meta‐analysis. Sensitivity analysis assessed the robustness of the results. When more than 10 papers were included, funnel plots were used to assess publication bias.

3. RESULTS

3.1. Study selection and quality assessment

The literature screening process is illustrated in Figure 1. A total of 328 studies were identified, and 201 duplicate papers were removed using Endnote X9 literature management software. Therefore, 127 studies were extracted. After reviewing titles and abstracts, 56 studies that did not meet the inclusion criteria were excluded. After carefully reviewing entire manuscripts, 41 studies were excluded. Finally, 30 studies were included. ¹¹ , ¹² , ¹³ , ¹⁴ , ¹⁵ , ¹⁶ , ¹⁷ , ¹⁸ , ¹⁹ , ²⁰ , ²¹ , ²² , ²³ , ²⁴ , ²⁵ , ²⁶ , ²⁷ , ²⁸ , ²⁹ , ³⁰ , ³¹ , ³² , ³³ , ³⁴ , ³⁵ , ³⁶ , ³⁷ , ³⁸ , ³⁹ , ⁴⁰ The included studies were published between 2002 and 2022, with sample sizes ranging from 46 to 222 patients. In total, 3158 patients were included, including 1574 patients treated with PFNA and 1584 patients treated with DHS. The included studies were of medium to high quality, and their basic characteristics are listed in Table 1.

FIGURE 1.

Flow diagram showing the systematic literature review and selection of studies.

TABLE 1.

Characteristics of the included studies.

Author	Year	Country	Number of patients		Age (Years)		Gender (male/female)		Outcomes	Jadad
			PFN (A)	DHS	PFN (A)	DHS	PFN (A)	DHS
Zeng	2017	China	110	112	74.34 ± 8.18	75.16 ± 8.8	40/70	45/67	1, 2, 3	4
Sarfraz	2022	Pakistan	40	40	59.2 ± 5.71	60.1 ± 4.48	23/17	25/15	1, 2	3
Adeel	2020	Pakistan	34	34	59.32 ± 2.39	60.88 ± 12.49	25/9	22/12	1, 2	3
Anshul	2022	Poland	40	40	21–90	21–90	21/19	22/18	1, 2, 3	3
Duymus	2019	Turkey	32	30	71.66 ± 10.59	72.13 ± 9.06	13/19	16/14	1, 2, 3	2
Gurung	2021	Nepal	26	26	56.35 ± 17.504	58.92 ± 17.609	18/8	17/9	1, 2	2
Gao	2017	China	45	45	79.2 ± 3.8		58/32		1	2
Huang	2010	China	48	48	75 ± 5	77 ± 5	6/42	19/29	1, 2	2
Mao	2020	China	60	60	64.88 ± 1.81	65.29 ± 1.29	32/28	31/29	1	2
Si	2020	China	50	50	73.57 ± 1.81	73.62 ± 1.85	25/25	26/24	1	2
Kassem	2022	Egypt	34	34	70.8 ± 7.7	68.7 ± 8.7	32/36		1, 3	3
Khan	2022	Narowal	35	35	55 ± 8.24	54.91 ± 8.56	15/20	13/22	1	4
Mohan	2019	India	30	24	60 ± 16	45 ± 14	18/12	16/8	1	2
Parker	2012	United Kingdom	215	215	82.4 (26–104)	81.4 (27–104)	52/248	69/231	1, 2, 3	5
Patil	2021	India	23	23	>21	>21	9/14	11/12	1, 2	3
Prakash	2022	India	23	23	65	61.09	12/11	9/14	1, 2	2
Qidwai	2019	India	40	40	>50	>50	29/11	24/16	1	2
Saleem	2020	Pakistan	54	54	58.54 ± 11.43	60.2 ± 11.37	31/23	37/17	1	4
Saudan	2002	Switzerland	100	106	83 ± 9.7	83.7 ± 10.1	24/76	22/84	1	3
Shukla	2022	India	85	77	61–70		40/45	38/39	1, 2	4
Cao	2021	China	45	45	61.86 ± 3.62	60.78 ± 3.24	21/24	20/25	1	3
Xue	2021	China	40	40	62.37 ± 7.49	62.51 ± 7.52	29/11	28/12	1	3
Zhang	2022	China	41	41	66.82 ± 5.13	64.64 ± 6.13	21/20	22/19	1	2
Zhu	2020	China	31	31	73.12 ± 3.53	72.35 ± 3.28	17/14	16/15	1	4
Nargesh	2014	India	48	48	68	67	15/33	11/37	1, 3	3
Xu	2010	China	51	55	78.5 ± 7.97	77.9 ± 7.82	15/36	16	1	4
Yadav	2016	India	38	54	55.64	55.81	26/12	22/32	1	3
Faisal	2016	India	50	50	66.8 (51–78)		NR	NR	1	2
Das	2020	India	75	75	68.6 (54–79)	68.8 (56–89)	21/54	27/48	1, 3	4
Sharmar	2018	India	31	29	60.67 (40–80)	62.27 (44–81)	19/12	19/10	1	3

Abbreviations: 1, Surgical site wound infection; 2, Superficial surgical site infection (SSI); 3, Deep SSI; DHS, Dynamic hip screw; PFN, Proximal femoral nail.

3.2. Surgical site wound infection

Thirty studies reported SSI. There were 41 cases of postoperative wound infections among the 1553 patients included in the PFNA group and 106 cases of postoperative wound infections among the 1567 patients included in the DHS group. The studies had no statistical heterogeneity (I ² = 0%, P = .62); therefore, the fixed‐effects model was used for the meta‐analysis. The meta‐analysis showed that the incidence of postoperative SSI was significantly lower in the PFNA group than in the DHS group (2.64% vs 6.76%, OR: 0.40, 95% CIs: 0.28–0.57, P < .001) (Figure 2).

FIGURE 2.

Forest plot showing differences between the use of PFNA and DHS in surgical site infections in patients with intertrochanteric fractures.

3.3. Superficial SSI

Seventeen studies reported superficial SSI. There were 25 cases of postoperative wound infections involving 969 patients in the PFNA group. However, 49 cases of postoperative wound infections involved 979 patients from the DHS group. The heterogeneity test showed no statistical heterogeneity between the studies (I ² = 0%, P = .67). Therefore, a fixed‐effects model was used for the meta‐analysis. The meta‐analysis findings showed that the incidence of postoperative superficial SSI was significantly lower in the PFNA group than in the DHS group (2.58% vs 5.01%, OR:0.53, 95% CI: 0.33–0.85, P = .008) (Figure 3).

FIGURE 3.

Forest plot showing differences between the use of PFNA and DHS in superficial SSI in patients with intertrochanteric fractures.

3.4. Deep SSI

Seven studies reported deep SSI. There were 7 cases of postoperative wound infections involving 554 patients in the PFNA group, and 19 cases of postoperative wound infections involving 554 patients in the DHS group. There was no statistical heterogeneity between the studies (I ² = 0%, P = .99). Therefore, a fixed‐effects model was used for the meta‐analysis. The meta‐analysis findings showed that the incidence of postoperative deep SSI was significantly lower in the PFNA group than in the DHS group (1.26% vs 3.43%, OR: 0.41, 95% CIs: 0.19–0.92, P = .03) (Figure 4).

FIGURE 4.

Forest plot showing differences between the use of PFNA and DHS in deep SSI in patients with intertrochanteric fractures.

3.5. Sensitivity analysis and publication bias

There was no significant heterogeneity among the studies. Subsequently, the results were reanalyzed by excluding one study at a time. No significant heterogeneity or effect was observed in the final results, indicating that the findings of the meta‐analysis were reliable. As shown in Figure 5, the funnel plot showed a largely symmetrical distribution among the studies. This indicated that there was no significant publication bias in the meta‐analysis findings.

FIGURE 5.

Funnel plot of the publication bias. (A) Surgical site infection. (B) Superficial SSI.

4. DISCUSSION

The surgical approach of choice for intertrochanteric fractures has always been controversial. Recently, however, there has been a yearly increase in the use of intramedullary fixation. Similarly, the use of extramedullary fixation has steadily declined. ⁴¹ DHS, a classical extramedullary fixation device, was once considered the “gold standard” for treating intertrochanteric fractures. DHS is suitable for stable intertrochanteric fractures and is advantageous in its ease of use, rapid recovery, and limited postoperative complications. Combined, these factors significantly improve the treatment outcome for intertrochanteric fractures. ⁸ , ⁹

PFNA is a modification of PFN. Its main feature includes the fact that the proximal end may be changed from two screws to a spiral blade. Consequently, the contact area with the bone is increased, and rotation is prevented. Therefore, PFNA is the most commonly used intramedullary fixation device for intertrochanteric fractures in clinical practice. ¹⁰ , ⁴² As the population continues to age, there will be a relative increase in the number of patients aged 45 and older with osteoporosis. The treatment of intertrochanteric fractures in these patients, especially unstable fractures with severe osteoporosis, is selected based on the operator's experience in clinical practice. Many clinical studies have reported using the abovementioned surgical modalities to treat intertrochanteric fractures. Even so, few studies on the effect of applying these procedures to postoperative incisional infections to treat intertrochanteric are available. Therefore, a meta‐analysis can provide a relatively reliable basis for selecting the best procedure for the clinical treatment of intertrochanteric fractures through a relatively rigorous evaluation with PFNA and DHS as the study subjects and by analysing a large number of previous studies with an evidence‐based medicine approach. PFNA is a modification of PFN.

This meta‐analysis included 30 studies investigating the effect of PFNA vs DHS on postoperative SSI in treating trochanteric fractures. The results showed that the incidence of postoperative SSI, superficial SSI, and deep SSI was significantly lower in patients treated with the PFNA group than in those treated with DHS. A meta‐analysis of 669 patients from six trials showed that PFNA significantly reduced operative times and intraoperative bleeding compared with DHS. However, there were no significant differences in the rate of postoperative wound infection and reoperation. ⁴³ In a prospective study of 52 patients with intertrochanteric fractures, Gurung et al. ¹⁷ showed that operative times were significantly reduced in patients treated with PFN than in those treated with DHS. Likewise, no significant difference was observed in the postoperative wound infection rate between the two groups. A study by Saudan et al. also identified similar findings. ²⁷ A recent meta‐analysis of 669 patients from 17 studies showed that PFNA significantly reduced the postoperative infection rate compared with DHS. ⁴⁴ These results are consistent with the findings of the present study.

To our knowledge, this meta‐analysis is the first to systematically compare the differences between PFNA and DHS in treating postoperative wound infections in intertrochanteric fractures. The included studies originate from several countries and regions worldwide. The diversity of these studies increases the generalizability of the conclusions and provides a reference for the clinical treatment of intertrochanteric fractures. However, this meta‐analysis still had the following limitations: (1) most of the included studies did not describe the implementation of the trial method with sufficient detail, which was a possible source of bias; (2) the small sample sizes of the included studies may have affected the accuracy of the conclusions; (3) because the studies were independently conducted, many confounding factors were difficult to control. Therefore, the external veracity of the results may have been impacted; and (4) differences in clinical experience and skill level of surgeons may have impacted postoperative outcomes and served as a source of bias.

5. CONCLUSION

PFNA significantly reduces the incidence of postoperative SSI in the treatment of intertrochanteric femoral fractures. Because of limitations in the number and quality of included studies, additional high‐quality studies are needed to validate our findings, improve the reliability of our conclusions, and provide an evidence‐based medicine approach for selecting the best surgical option to treat postoperative surgical wound infections in intertrochanteric fractures in clinical practice.

Dai P, Zhou H, Mao X, Liu C, Wang Z, Kang Y. Proximal femoral nail anti‐rotation vs dynamic hip screws decrease the incidence of surgical site infections in patients with intertrochanteric fractures: A meta‐analysis. Int Wound J. 2023;20(8):3212‐3220. doi: 10.1111/iwj.14200

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are available from the corresponding author upon reasonable request.