Introduction

Hip fractures typically occur in older adults following low-energy trauma, such as falls, and are associated with high rates of morbidity and mortality.1 Although the annual incidence of these fractures worldwide was approximately 1.3 million in 1990, this figure is estimated to exceed 6 million by 2050 due to population aging.1-3 Although a slight decrease in the incidence of hip fractures has been observed in countries such as the United States, attributed to multiple factors including increased awareness of osteoporosis, the risk of falls,4,5 and the implementation of fall prevention strategies,6 their impact on public health remains significant due to the high risk of complications and adverse outcomes.1-4

Approximately 330 000 hip fractures occur each year in the United States, with an incidence of 78.7 cases per 10 000 people in 2006 and a mortality rate of between 20% and 24% in the first year following the fracture.5 In Latin American countries, incidences of 138.5–177 per 100 000 inhabitants and annual mortality rates of 9.5%–24% in the year following the fracture are reported.7,8 Although there are no general epidemiological data on hip fractures in Peru, single-center studies conducted on older adults treated at the Cayetano Heredia National Hospital and the Luis N. Saenz PNP Central Hospital between 2013 and 2018 report that the majority of those affected were women (54.3%–71%), the intertrochanteric fracture was the most common type of fracture (60%–64%), surgical treatment was predominant (69.2%–88.5%), and 61.5% of patients who underwent surgery experienced complications.9,10

Complications following hip fractures are wide-ranging, diverse, and multifactorial, and include delirium, deep vein thrombosis, anemia, heart failure, functional impairment, and, in patients who undergo surgical treatment, problems related to the procedure and the osteosynthesis hardware, such as infections, postoperative pain, hemorrhage, neurovascular injury, fixation device failure, nonunion, avascular necrosis, limb length discrepancy, and periprosthetic fractures.1,11,12

Although the definitive management of these fractures depends largely on the location and configuration of the injury, the primary goal of treatment is to restore the patient’s mobility as soon as possible; therefore, surgery is the preferred option in most cases. In fact, conservative management has been reported to be associated with higher mortality at 30 days and 1 year, which is why this treatment is reserved solely for patients who are not candidates for surgery.1 In this context, early surgery is associated with better outcomes, and therefore, surgery is recommended within the first 48 hours after admission.1,6 However, in resource-limited countries such as Peru, there are structural barriers, which are insufficiently documented, that prevent timely intervention.

Intertrochanteric fractures are defined as extracapsular fractures of the proximal femur that occur between the greater and lesser trochanters.13 These injuries are more common in older adults with osteoporosis due to low-energy trauma, and it is estimated that at least half of all hip fractures are intertrochanteric.13 Furthermore, this type of fracture is more common in women, with a female-to-male ratio ranging from 2:1 to 8:1.13

Given the above, the objectives of this study were to describe the clinical characteristics of patients aged 60 years or older with intertrochanteric fractures treated at the Hipólito Unanue National Hospital (Peru) and to identify the risk factors associated with delayed surgical management (>48 hours after admission).

Study Type

Retrospective cohort study.

Study Population and Sample

The study population consisted of patients with intertrochanteric fractures treated between January and December 2023 at the Hipólito Unanue National Hospital (tertiary care facility) in Lima, Peru (n=60). Patients aged ≥60 years with a diagnosis of intertrochanteric fracture confirmed by X-ray and who received initial treatment at the institution were included. Medical records of patients with pathological fractures were excluded. Thus, a sample of 51 individuals (51 fractures) was obtained (Figure 1).

Figure 1. Sample selection flowchart.

Source: Author’s own work.

Statistical Power Analysis

A post-hoc power analysis was performed using G*Power 3.1 for the subgroup of patients who underwent surgery (n=23; early n=5, late n=18). An α=0.05 was considered, and Fisher’s exact test was used for dichotomous variables. For the variable ‘immediate availability of surgical management’, with proportions p₁=1.00 (early management) and p₂=0.33 (late management), the power was high (89.8%) and the effect size φ was 0.55 (large effect). In the case of anemia, with p₁=0.40 and p₂=0.83, the power was 43.3% and φ=0.41 (moderate effect). For urinary tract infection, with p₁=0.00 and p₂=0.22, the power was practically nil (0.21%) and φ=0.24 (small effect). Effect size was interpreted according to Cohen’s criteria as small (≤0.29), moderate (0.30–0.49), or large (≥0.50). These results indicate that the study had sufficient power only to detect the primary association related to surgical availability, while associations with comorbidities should be interpreted as exploratory. The post-hoc power analysis is not intended to validate associations, but rather to contextualize the risk of Type II error, especially in variables with small sample sizes and unbalanced subgroups.

Variables

Data on the following variables were collected through a review of medical records: age; sex; body mass index (BMI); presence of overweight or obesity based on BMI; presence of comorbidities such as anemia, hypertension, diabetes mellitus, urinary tract infection, osteoporosis, and hypothyroidism; fracture side; fracture type according to the AO classification; fracture stability, with 31A1 fractures considered stable and 31A2 and 31A3 fractures considered unstable; fracture alignment, classified as varus, valgus, or normal based on evaluation of the anteroposterior hip radiograph; type of management, surgical or non-surgical; and mortality.

For patients who underwent surgical treatment, additional information was collected on the time elapsed between admission and surgery; the duration of the surgical procedure; proper placement of the head screw, defined as a central or centro-inferior position of the screw in the anteroposterior and lateral views, according to accepted radiographic criteria; and the unavailability of surgical management, defined as the absence of essential hospital resources required to perform surgery (operating room, surgical team, C-arm, blood units, among others) in clinically eligible patients due to the hospital’s logistical limitations.

Statistical Analysis

Categorical variables are described using absolute frequencies and percentages, and continuous variables using means and standard deviations, as the data followed a normal distribution (Shapiro-Wilk test).

Bivariate analyses (Fisher’s exact test and the nonparametric Mann–Whitney U test) were performed to evaluate, on the one hand, differences between patients who underwent early surgical management (<48 h after admission) and those who underwent late surgical management; and on the other hand, differences in mortality between patients who received conservative treatment and those who underwent surgical management. To explore factors associated with delayed surgical management (>48 h after admission), a multivariate analysis was performed using a binary logistic regression model and the calculation of odds ratios (OR) and their respective 95% confidence intervals (95% CI). A level of statistical significance of p<0.05 was considered. All statistical analyses were performed using Epi Info v7.2 and SPSS v28.

Ethical Considerations

This study was approved by the Research Ethics Committee of the Hipólito Unanue National Hospital, Lima, Peru, under file No. 24-026808-01 dated September 9, 2024. The research complied with the ethical principles of the Declaration of Helsinki,14 since all data were collected retrospectively from medical records; individual informed consent was not required, and the confidentiality of the information was always respected.

Results

Patient characteristics

The mean age of the patients was 80.23 years (SD: 8.46), and 64.71% (n=33) were women. The most common comorbidities were anemia (64.71%), hypertension (39.22%), type 2 diabetes mellitus (23.53%), urinary tract infection (11.76%), and osteoporosis (9.8%). The mean BMI was 23.36 kg/m² (SD: 2.94), with a low prevalence of overweight (5.26%) and obesity (2.56%) (Table 1).

The left side was affected most frequently (52.94%); 58.82% of the fractures were unstable, 72.55% had varus alignment, and 50.98% were classified as 31A1 according to the AO system (Table 1). Regarding treatment, 54.9% of patients received non-surgical management (skin traction and progressive mobilization according to tolerance).

In the surgical treatment subgroup (n=23), the average time between admission and surgical management was 18.30 days (SD: 8.68), the average duration of surgery was 95.40 minutes (SD: 33.02), and proper placement of the cephalic screw was achieved in 65.21% of patients. Surgery was not immediately available for 78.26% (n=18) of these patients (Table 1).

Table 1. Clinical characteristics of patients with intertrochanteric fractures treated at a hospital in Lima.

Variable	n (%)
Age (years) – mean (SD)	80.23 (±8.46)
Sex
Female	33 (64.71)
Male	18 (35.29)
BMI – mean (SD)	23.36 (±2.94)
Overweight	2 (5.26)
Obesity	1 (2.56)
Comorbidities
Anemia	33 (64.71)
Mild	17 (51.52)
Moderate	13 (39.39)
Severe	3 (9.09)
Arterial hypertension	20 (39.22)
Type 2 diabetes mellitus	12 (23.53)
Urinary tract infection	6 (11.76)
Osteoporosis	5 (9.80)
Hypothyroidism	2 (5.26)
Fracture laterality
Right	24 (47.06)
Left	27 (52.94)
AO Classification
31A1	26 (50.98)
31A2	20 (39.22)
31A3	5 (9.80)
Fracture stability
Unstable	25 (49.02)
Stable	26 (50.98)
Alignment
Varus	37 (72.55)
Normal	12 (23.53)
Valgus	2 (3.92)
Type of treatment
Non-surgical	28 (54.90)
Surgical	23 (45.10)
Surgical waiting time (days) – mean (SD)	18.30 (8.68)
Average duration of surgery (minutes) – mean (SD)	95.43 (33.02)
Adequate placement of the cephalic screw (n=23)
Yes	15 (65.21)
No	8 (34.79)
Immediate availability of surgical management (n=23)
No	12 (52.17)
Yes	11 (47.82)
Mortality
Yes	8 (15.69)
No	43 (84.31)

SD: standard deviation.

BMI: body mass index.

Source: Author’s own elaboration.

In total, 8 patients died (15.69%), all of whom were in the conservative management group (28.57% vs. 0%; p=0.0057) (Table 2).

Table 2. Distribution of one-year mortality by type of management in patients with intertrochanteric fractures.

Management	Deceased	Survivors	Total	p-valor
Non-surgical	8	20	28	0,0057ª
Surgical	0	23	23
Total	8	43	51

aFisher’s exact test.

Source: Authors’ own calculations.

Furthermore, statistically significant differences were found between patients who underwent early surgical management (<48 hours after admission) and those who underwent delayed surgical management regarding the presence of anemia (p=0.04), surgical waiting time (p<0.001), and unavailability for surgical management (p=0.002) (Table 3).

Table 3. Clinical characteristics by group.

Variable	Early surgical management (n=05) n (%)	Delayed surgical management (n=18) n (%)	p-value
Age (years) – mean (SD)	78.20 (±7.80)	82.1 (±7.80)	0.35ª
Sex
Female	3 (60.00)	12 (66.70)	0.99ᵇ
Male	2 (40.00)	6 (33.30)	0.99ᵇ
BMI – mean (SD)	23.10 (±2.80)	23.40 (±3.00)	0.85ª
Overweight	1 (20.00)	1 (5.60)	0.39ᵇ
Obesity	0 (0)	1 (5.60)	0.99ᵇ
Comorbidities
Anemia	2 (40.00)	15 (83.30)	0.04ᵇ
Mild	2 (40.00)	6 (33.30)	0.99ᵇ
Moderate	0 (0)	7 (38.90)	0.15ᵇ
Severe	0 (0)	2 (11.10)	0.99ᵇ
Arterial hypertension	1 (20.00)	7 (38.90)	0.63ᵇ
Type 2 diabetes mellitus	1 (20.0)	5 (27.80)	0.99ᵇ
Urinary tract infection	0 (0)	4 (22.20)	0.54ᵇ
Osteoporosis	0 (0)	2 (11.10)	0.99ᵇ
Hypothyroidism	0 (0)	0 (0)	-
Fracture laterality
Right	3 (60.00)	9 (50.00)	0.67ᵇ
Left	2 (40.00)	9 (50.00)	0.67ᵇ
AO Classification
31A3.1	3 (60.00)	10 (55.60)	0.52ᵇ
31A3.2	2 (40.00)	6 (33.30)	0.52ᵇ
31A3.3	0 (0)	2 (11.10)	0.52ᵇ
Fracture stability
Unstable	3 (60.00)	11 (61.10)	0.99ᵇ
Stable	2 (40.00)	7 (38.90)	0.99ᵇ
Fracture alignment
Varus	4 (80.00)	13 (72.20)	0.78ᵇ
Normal	1 (20.00)	4 (22.20)	0.78ᵇ
Valgus	0 (0)	1 (5.60)	0.78ᵇ
Surgical waiting time (days) -mean (SD)	1.20 (±0.40)	22.50 (±5.70)	<0.001ª
Average duration of surgery (minutes) – mean (SD)	89.40 (±12.10)	97.30 (±15.60)	0.28ª
Adequate placement of the cephalic screw (n=23)
Yes	4 (80.00)	11 (61.10)	0.62b
No	1(20,00)	7(38,90)	0.62b
Immediate availability of surgical management (n=23)
No	6 (33.30)	12 (66.70)	0,002b
Yes	5 (100)	0 (0)	0,002b

ᵃMann-Whitney U test.

ᵇFisher’s exact test.

Source: Authors’ own elaboration.

Regarding the multivariate analysis (adjusted model), the lack of immediate surgical management showed the strongest association with delayed surgical management (adjusted OR = 6.0; 95% CI: 2.0–18.0; p= 0.001); furthermore, this variable had a high effect size in the statistical power analysis. Although positive associations were also found between delayed surgical management and the presence of anemia (adjusted OR = 4.9; 95% CI: 0.8–30.1; p=0.082) and urinary tract infection (adjusted OR = 3.5; 95% CI: 0.6–20.4; p=0.162), their magnitude was smaller and they were not statistically significant (Table 4). Furthermore, it should be noted that the statistical power analysis showed low-to-moderate power for these two variables.

Table 4. Results of the exploratory multivariate analysis for delayed surgical management (>48 h).

Variable	Adjusted OR (95% CI)	p-value	VIFª
Non-availability of immediate surgical management.	6.0 (2.0-18,0)	0.001	1.1
Anemia.	4.9 (0.8-30.1)	0.082	1.1
Urinary tract infection.	3.5 (0.6-20.4)	0.162	1.1

ªVariance inflation factor.

Source: Author’s own elaboration.

Discussion

Intertrochanteric fractures in older adults represent a complex clinical challenge due to the frequency of comorbidities and the frailty of geriatric patients.5 In our cohort of patients >60 years of age with intertrochanteric fractures, women predominated (64.71%), which is similar to what has been reported in national (67.3%–71%)9,15,16 and international studies (66.2%–70.47%),17-19 conducted on older adults with hip fractures. Furthermore, in this study, the average age was 80.2 years, a finding relatively consistent with that described in studies on hip fractures in Peru (patients >60 years), where the mean or median age ranged from 66 to 83.9,15 as well as in other countries such as the United States and China, where mean or median ages of between 80.7 and 82 years are reported.17,18

In this study, anemia was the most prevalent comorbidity (64.7%), a finding consistent with reports in the international literature, where its prevalence in older adults with hip fractures ranges from 68% to 72%.20,21 This was followed by hypertension (39.2%), with a lower frequency than that described in those same series (46%–88%), and type 2 diabetes mellitus (23.5%), both within previously reported ranges.20-22 These findings reflect a high clinical burden that requires a multidisciplinary orthogeriatric approach.9,10,12

The proportion of non-surgical management was considerably high (54.9%) compared to that reported in a study from Tunja, Colombia (7.02%).7 However, Rondón et al.10 reported an even higher rate (88.5%) at a local hospital in Peru.10 Internationally, surgery is the standard of care in more than 90% of cases.17,18 This situation reflects both the structural overload of the public health system (limited availability of operating rooms, insufficient critical resources, and the absence of prioritization protocols) and the influence of comorbidities and risk factors on clinical decision-making.9 In our cohort, 78.26% of patients undergoing surgery did not have immediate hospital availability for the procedure, highlighting the direct impact of structural limitations on the observed surgical delay.

In this study, the average surgical waiting time was alarmingly long (18.3 days), as international guidelines recommend performing the procedure within the first 48 hours following the injury.6,11-13 This delay increases the risk of infections, cardiovascular complications, functional loss, and mortality. 23 The variable with the greatest impact on the delay was the lack of immediate availability of surgical management (OR=6.0), followed by anemia (OR=3.2) and urinary tract infection (OR=4.1); however, it should be noted that the latter two showed low-to-moderate power in the statistical power analysis, so their association must be corroborated by further studies. Consistent results were reported by Huamán-Díaz et al.16 at the Regional Hospital of Lambayeque, Peru, where the same factors were significantly associated with surgical delay (median: 5.29 days), confirming that structural limitations and comorbidities are common determinants across different hospitals in the country.16 These results emphasize the urgent need to optimize care for these patients in Peru by developing and implementing strategies to increase the likelihood of surgical management within 48 hours of admission, through improvements in hospital capacity, particularly the immediate availability of resources for surgical management.

Several studies, including a meta-analysis, have shown that surgical interventions within the first 48 hours significantly reduce mortality24,25 and improve functional recovery.26 In our cohort, one-year mortality was 15.69%; all these patients had been treated conservatively. However, the international literature shows much higher mortality rates when comparing patients with non-surgical treatment versus surgical treatment: Dobre et al.27 report 56.4% vs. 24.5% in Romania,27 Mathur et al.28 report 20.7% vs. 3.8% in the United States with a Hispanic cohort,28 and Tan et al.29 report 33.05% vs. 8.96% in Singapore.29 Although the differences may be due to factors such as patient selection, comorbidities, or availability of support, all studies agree that conservative management is associated with higher mortality.27-29 In Peru, there are still no studies that directly compare both approaches, which represents a significant knowledge gap.

The limitations of this study include the fact that it is a single-center, retrospective analysis, and particularly the small size of the subgroups of interest (delayed surgical management: n=18 vs. early: n=5). Nevertheless, it is one of the few studies in Peru that specifically analyzes intertrochanteric fractures and identifies factors associated with delayed surgical management. Likewise, the post-hoc power analysis performed should be interpreted as a tool to contextualize the limitations arising from the sample size and the risk of Type II error, and not as confirmation of the observed associations, which should be considered exploratory. In this regard, larger, multicenter studies are needed to confirm the association of these factors.

Conclusions

In the present study, the proportion of surgical management is very low compared to that reported in international studies. Similarly, delayed surgical management (>48 h) was very common, and the average time between admission and surgery was prolonged (18.3 days); the lack of immediate availability of surgical management was associated with delayed surgical management. Furthermore, the presence of anemia and urinary tract infections suggests an exploratory association with delayed surgical management, although the statistical power was low to moderate; therefore, these results require confirmation in future studies. These findings highlight the need to implement strategies within the institution to increase the frequency of early surgical management in these patients, with an emphasis on resolving the issue of the lack of immediate availability of surgical management.

Conflicts of interest

None reported by the authors.

Funding

Self-funded by the authors.

Acknowledgments

None reported by the authors.

Use of Artificial Intelligence

Artificial intelligence tools were used as bibliographic search engines. All sources were independently reviewed and verified by the authors.

References

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