Evaluating the Costs of Surgically Managed Ankle Fractures Treated in an Inpatient vs Outpatient Setting: A Systematic Review and Meta-analysis

Abstract

Background:

Ankle fractures are prevalent, with 21% to 40% of cases requiring surgical intervention. Treatment decisions regarding non-complex fractures, whether in an inpatient (IP) or outpatient (OP) setting, are often influenced by local resource availability. Although IP care is generally expected to be more expensive, the magnitude of this difference and its interpretation across heterogeneous cost definitions, health care systems, and operative settings remain unclear. This systematic review and meta-analysis evaluates the cost differences between IP and OP surgical management of isolated ankle fractures, offering evidence to guide surgeons in optimizing care pathways while minimizing health care expenditures.

Methods:

This PROSPERO-registered systematic review and meta-analysis (CRD420251134624) of comparative studies evaluated cost differences for OP and IP management of ankle fractures. We queried PubMed, EMBASE, and CINAHL from inception through August 17, 2025. Because of the inconsistent definition “cost” across the literature, we extracted and analyzed the cost construct as defined by each included study and performed a random effects meta-analysis of the unstandardized mean differences (standardized to a common price year/currency)and reported them with 95% CIs.

Results:

Seven articles were included, with a final sample size of 21,955 patients with an average age of 43.50 ± 2.87 years and a 2.5-month mean follow-up. Overall, 53.8% (n = 11 813) of patients were treated in the IP setting and 46.2% (n = 10 142) were treated in the OP setting. The mean hospital length of stay (LOS) for IPs was 2.27 ± 0.25 days across the 5 studies reporting this value (n = 5718 IP patients). The average study reported direct cost for IP management was significantly higher than OP management ($11 236.37 ± $2205.05 vs $6990.18 ± $1670.72; P = .011, CI: 1654.50, 6920.19). Qualitatively, the safety and complication profiles between IP and OP were not different among 3 studies that examined this metric.

Conclusion:

Outpatient ORIF for isolated ankle fractures is associated with lower study-reported economic burden than inpatient management in appropriately selected patients, without clear evidence of worse short-term safety outcomes in the available comparative literature. These findings support outpatient pathways for patients with acceptable reduction and immobilization, manageable soft tissues, limited comorbidity burden, safe non-weightbearing mobility, and reliable follow-up. Because included studies used heterogeneous economic definitions and were observational, future prospective studies should use standardized economic outcomes and longer follow-up to better define the value of outpatient vs inpatient care.

Introduction

Ankle fractures are among the most common fractures in adults, with reported incidence estimates ranging from approximately 42 to 179 per 100 000 person-years across US, European, and Asian populations.^1-5 They account for nearly 10% of all fractures, and most often occur in younger men and postmenopausal women, with prior literature estimating that 21% to 40% of ankle fractures require surgical intervention.^1-3,5-7 Surgery with open reduction and internal fixation (ORIF) is generally indicated in unstable Weber B and C fractures, bi- and trimalleolar fractures, and those with associated syndesmotic injury or talar shift.^8-11

Outpatient (OP) management is appropriate for most isolated, closed ankle fractures in medically stable patients with few comorbidities who have reliable support at home. This includes many unimalleolar and bimalleolar injuries and select trimalleolar patterns where soft tissues are suitable and pain can be controlled appropriately.^12-15 Inpatient (IP) care is indicated for polytrauma situations, open fractures, and urgent problems such as neurovascular compromise, irreducible dislocation or severe soft tissue injury, and for patients with substantial comorbidity burden who will require a period of hospitalization for medical management.^12-15 For otherwise healthy patients with isolated, closed fractures that can be safely reduced, immobilized, and managed with reliable follow-up, OP care may represent an opportunity to de-escalate the acuity of care while preserving safety. In these cases, the decision often reflects local resources, including access to outpatient operating time in ambulatory surgery centers or hospital outpatient departments (HOPDs), inpatient bed availability, and the ability to coordinate timely follow-up and perioperative support.^13,14 OP pathways may be limited by constrained outpatient operating schedules or more limited access to overnight nursing observation, immediate inpatient medical consultation, therapy evaluation, or postoperative monitoring, whereas IP admission can prolong hospital stay, detract patients from returning to work or daily ambulatory activities, and increase risk of exposure to nosocomial infection.^13-17 The choice of setting carries meaningful financial implications for health systems and patients. In the United States, health spending accounted for 16.4% of gross domestic product in 2013 (~$9000 per person), and more than 2½ times the average of other industrialized nations.^12,13 Foot and ankle surgery in particular accounts for an annual $11-billion economic burden, with ankle fractures accounting for 10% of this cost. ¹⁸

Moving eligible orthopaedic procedures to OP settings has been associated with substantial cost savings without compromising outcomes when patients are appropriately selected. As payment models emphasize value, bundled episodes, and avoidance of unnecessary resource use, surgeons and administrators must understand the cost impact of surgery setting and align pathways that maintain safety while reducing avoidable IP utilization. ¹⁸ Although a growing number of comparative studies now examine costs for isolated ankle ORIF performed in OP and IP settings, they are limited by a lack of clear guidance for surgeons without any existing pooled analysis to deliver a clear summary of the incremental cost difference with contextual safety outcomes across settings.

Although it may be intuitively expected that OP surgery could be less expensive than IP admission, the practical question for clinicians and systems is not the direction of effect but the magnitude and context: How large is the incremental difference on a common scale, how consistent is it across health systems with different input prices and accounting methods, and what operational constraints (eg, ambulatory capacity, time-to-surgery, perioperative support) and patient-selection factors shape whether cost reductions can be realized without compromising safety? A pooled estimate framed in interpretable dollar units can inform pathway design, staffing and operating room planning, and value-based payment discussions. Therefore, we performed a systematic review and meta-analysis not simply to investigate whether OP care is less expensive, but to estimate the magnitude of the study-reported economic difference, assess how consistently this difference is observed across heterogeneous economic definitions and health care systems, and synthesize the patient-selection and implementation factors that determine when OP ankle ORIF pathways are clinically feasible.

Methods

Study Registration and Guideline Adherence

This study is a systematic review of comparative studies examining the cost differences of IP vs OP management of isolated ankle fractures. This study was pre-registered on the International Prospective Register of Systematic Reviews (PROSPERO) prior to the article sorting process (CRD420251134624). Additionally, this study was conducted under the guidance of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

Study Creation with Search Strategy

This systematic review searched PubMed, Embase, and CINAHL from database inception until August 17, 2025, using the following search algorithm: (Cost OR Costs) AND (“ankle fracture” OR “ankle fractures”) AND (outpatient OR “Episode-of-care” OR “Ambulatory Surgical Center”) AND (inpatient OR “Level-1 trauma center” OR “hospital setting”).

Inclusion and Exclusion Criteria

Inclusion criteria were comparative articles that compared any cost parameters for the surgical management of isolated ankle fractures without associated lower extremity polytrauma between IP and OP settings, articles with full-text, articles that were randomized controlled trials (RCTs) or comparative observational retrospective or prospective studies, and articles in English. Exclusion criteria were articles that did not examine and compare both IP and OP settings, articles that did not report data on cost, case reports, systematic reviews, meta-analyses, books, and noncomparative studies.

Article Selection Process

The article screening process was completed by 2 authors, with any conflicts in decisions being resolved by a third author. After the initial database search, all retrieved articles were uploaded into Rayyan, a systematic review screening interface, to facilitate the sorting process. ¹⁹ First, duplicate articles were removed and then articles were sorted by title and abstract. Next, articles were sorted by full text. On the final inclusion of any articles, a full reference search of the included articles was completed.

Study Definitions

The primary outcome was the difference between IP and OP management in the study-reported economic amount for surgically treated isolated ankle fractures among studies with extractable arm-level economic data. Secondary outcomes included hospital length of stay, time-to-surgery, episode-of-care costs or expenditures when reported separately from the primary economic construct, complications, readmissions, emergency department visits, and other perioperative characteristics. Because the term “cost” is used variably in the literature, this outcome was not assumed to represent a uniform activity-based or hospital-accounting cost. Depending on the original study and data source, reported values may reflect institutional direct costs, charges, payer payments, allowed amounts, claims-derived expenditures, or episode-of-care spending. For each included study, we extracted the economic construct exactly as defined by the authors and recorded its source, scope (eg, index hospitalization direct costs vs episode-of-care or 90-day expenditures), and time horizon. Accordingly, the pooled estimate should be interpreted as a synthesis of study-reported economic burden rather than a direct comparison of true costs across health care systems.

Data Extraction Process

Data extraction was completed by a single author. Once a final data set was obtained, another author independently verified all of the data for accuracy. Data extracted included first author, year of publication, number of patients, sex, follow-up time, setting, study-reported economic data, including the reported cost construct, data source, included cost components, and time horizon, complications, perioperative characteristics, and key findings in narrative form with P values. No patient-level data imputation was performed. When study-level economic data were missing, not reported by treatment arm, or not extractable as arm-level mean values for both IP and OP groups, the study was retained in the systematic review but excluded from the quantitative mean-difference meta-analysis and summarized narratively. When means were reported without SDs, the SDs were imputed from the most comparable included study.

Article Quality Grading

All observational studies included in this systematic review were classified as “comparative” and graded for their level of quality using the Methodological Index for Non-Randomized Studies (MINORS) scale. ²⁰ Comparative studies were graded out of 24 points with 12 items on the scale with each item being rated from 0 to 2 points. All articles were considered to be “high-quality,” “moderate-quality,” or “low-quality” based on their scoring. High-quality articles scored 24 points, moderate-quality articles scored 15 to 23 points, and low-quality articles scored less than 15 points. ²¹

Certainty of Evidence Assessment

The overall certainty of evidence was assessed using the GRADE framework and can be seen summarized in Table 1. Because all included studies were observational, the certainty assessment began at low. Certainty was further downgraded when appropriate for risk of bias, inconsistency, indirectness, imprecision, and publication bias. The primary economic outcome was rated as very low certainty because of observational study design, heterogeneity in economic constructs and time horizons, and cross-national differences in health care systems and accounting methods. Secondary safety and utilization outcomes were also rated as very low certainty because of residual confounding, inconsistent outcome reporting, and short follow-up.

Table 1.

GRADE Certainty of Evidence Assessment.

Outcome	Certainty	Reason
Primary economic outcome	Very low	Observational studies, heterogeneous cost constructs, cross-national indirectness, variable time horizons
Complications/readmissions/ED utilization	Very low	Observational studies, residual confounding, inconsistent reporting, short follow-up
Length of stay/time-to-surgery	Very low	Observational studies, setting-dependent practice patterns, inconsistent reporting

Abbreviation: ED, emergency department.

Statistical Synthesis

All analyses were performed in IBM SPSS Statistics version 29.0 (IBM Corp). The primary meta-analysis was limited to the study-reported economic outcome. Secondary outcomes were summarized descriptively or narratively because of inconsistent definitions, incomplete reporting, and limited availability of arm-level data. These secondary analyses were considered exploratory rather than confirmatory hypothesis testing. Descriptive statistics (eg, frequency-weighted means and percentages) were reported where hypothesis testing was not applicable. For the meta-analysis of cost outcomes, we first standardized all study-level costs to a common reference year and currency (USD, 2025) by inflating country-specific costs to the target price year using national consumer price indices and converting across countries using purchasing power parity factors based on the Organisation for Economic Co-operation and Development (OECD) Economic Outlook (Appendix Tables A and B). This standardization placed values on a common price-year and currency scale but did not eliminate heterogeneity in underlying economic constructs, accounting methods, payer mix, health-system structure, or time horizon. We then conducted a random effects meta-analysis of (USMDs) for cost between procedure setting, reported with 95% CIs. Using raw mean differences in a standardized currency preserves direct interpretability in dollars, which is essential for economic evaluation and for linking to cost-effectiveness metrics (eg, incremental cost effectiveness ratios or net monetary benefit). Unlike standardized mean differences (SMDs), USMDs do not confound the effect size with between-study variability in SMDs, and after explicit inflation and currency standardization, they remain comparable across years and countries while retaining policy-relevant units. Study weights were computed using inverse-variance methods. Where studies reported means without SDs, we used SDs from the most comparable study consistent with the literature.^22-24 Results were presented with heterogeneity statistics (Q, τ², and I²) and a prediction interval. Forest plots were generated to visualize study-level effects and the pooled estimate.

Results

Initial Search Results and Article Grading

The database search resulted in 52 articles; after manual de-duplication, 22 articles remained. After title and abstract screening, 7 articles were included in full-text analysis. Ultimately, 7 total articles met inclusion criteria and were included in the data extraction process (Figure 1).

Figure 1.

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses diagram.

Article Quality Results

Of the 7 included studies, all were comparative in nature. Mean MINORS score for comparative studies was 18.28 ± 0.75 (out of 24.0 points). Ultimately, all included articles were “moderate quality,” with no “high quality” or “low quality” articles included in this study (Table 2).

Table 2.

The Methodological Index for Non-Randomized Studies (MINORS) Grading for the Individual Articles Included in This Systematic Review. ^a

Author (Year)	Study Type	Total MINORS Score	Clearly Stated Aim	Inclusion of Consecutive Patients	Prospective Collection of Data	End Points Appropriate to Study Aim	Unbiased Assessment of Study End Point	Follow-up Period Appropriate to Study Aim	Less Than 5% Lost to Follow-up	Prospective Calculation of the Study Size	Adequate Control Group	Contemporary Groups	Baseline Equivalence of Groups	Adequate Statistical Analysis
Khaka et al 25 (2020)	Comparative	18	2	1	2	2	1	2	1	0	2	2	1	2
Barfield et al 26 (2022)	Comparative	18	2	1	0	2	2	2	2	0	2	2	1	2
Varacallo et al 18 (2018)	Comparative	18	2	1	0	2	2	2	2	0	2	2	1	2
Pasic et al 14 (2022)	Comparative	17	2	1	0	2	1	2	2	0	2	2	1	2
Malik et al 13 (2020)	Comparative	19	2	2	0	2	1	2	2	0	2	2	2	2
Bettin et al 12 (2019)	Comparative	19	2	2	0	2	1	2	2	0	2	2	2	2
Thangathurai et al 27 (2024)	Comparative	19	2	2	0	2	2	2	2	0	2	2	1	2

^aComparative studies scored 0-24 points.

Study Baseline Characteristics

We identified 21 955 patients across the 7 comparative studies included in this systematic review and meta-analysis. Across the 5 studies that reported gender demographics, we identified that 70.84% of patients were female (n = 3832) with a frequency weighted mean (FWM) age of 43.50 ± 2.87 years. More than half (53.81%) of the cohort was in the IP group (n = 11 813), with the remaining 10 142 patients (46.19%) in the OP group. The FWM follow-up period was 2.5 months. Patient with IP treatment generally experienced a mean hospital length of stay (LOS) 2.27 ± 0.25 days. Key findings and takeaways from each study can be found in Table 3.

Table 3.

Demographic Table of Study and Patient Characteristics. ^a

Author (Year)	Inpatient vs Outpatient	No. of Patients	Mean Age (y)	Sex	Follow-up Time (mo)	Length of Stay (d)	Preferred Procedure	Reasoning
Khaka et al 25 (2020)	IP	5	45.3	M = 7, F = 10	-	-	OP	Patients can be safely managed OP with regular clinic review before formal operative intervention vs blanket admission to an acute IP bed.
	OP	12
Barfield et al 26 (2022)	IP	6090	-	-	-	1.5-10.4	OP	ORIFs done in OP ASCs represent the lowest cost option available.
	OP	2842				-
Varacallo et al 18 (2018)	IP	201	43 ± 14	M = 126, F = 173	3 mo	2.7 ± 2.3	OP	OP cases cost significantly less than IP cases (P < .001) and cost roughly two-thirds of the IP cost.
	OP	98				-
Thangathurai et al 27 (2024)	IP	14	41.4	M = 60, F = 45	-	6.9 d	OP	IP care was associated with higher study-reported costs than OP care.
	OP	91				-
Pasic et al 14 (2022)	IP	125	42.0 ± 17.5	M = 50, F = 75	1 mo	2 d	OP	Length of stay and costs were significantly higher for the IP group compared to the OP group. Operative time was slightly shorter for the outpatient group but not by a substantial margin.
	OP	71	44.2 ± 16.0	M = 40, F = 31		<1 d
Malik et al 13 (2020)	IP	5317	-	M = 647, F = 1749	3 mo	2.25 d	OP	OP management was associated with lower study-reported 90-d economic burden than IP management.
	OP	6941		M = 647, F = 1749		<1 d
Bettin et al 12 (2019)	IP	61	52.8	-	3 mo	1.7 d	OP	OP care was associated with lower study-reported cost than IP care, with no significant difference in revision surgery, readmissions, or emergency department visits.
	OP	87	42.5			0.8 d

Abbreviations: ASCs, ambulatory surgery centers; IP, inpatient; OP, outpatient; ORIFs, open reduction and internal fixation procedures.

^aPreferred procedure indicates which modality the individual study recommended along with the rationale for supporting their findings.

Direct Costs of Inpatient vs Outpatient Operative Isolated Ankle Fracture Management

The FWM reported direct costs for patients who underwent IP management for ankle fractures was $11 236.37 ± $2205.05 as compared with $6990.18 ± $1670.72 for patients who underwent OP management (Table 4). This corresponded to an approximately 37.8% lower study-reported economic amount for OP management relative to IP management. This percentage reflects a descriptive comparison of frequency-weighted means across studies with heterogeneous economic constructs and should not be interpreted as a pooled analytic estimate. When examining the 5 included studies via random effects pooled meta-analysis, we found IP management (n = 5662) was associated with significantly higher direct costs compared with OP management (n = 7213) (P = .011; USMD = 4287.34; 95% CI: 1654.50, 6920.19; Figure 2).

Table 4.

Study-Reported Economic Values for Inpatient (IP) and Outpatient (OP) Management of Isolated Ankle Fractures Among Studies With Extractable Arm-Level Data Included in the Quantitative Meta-analysis.

Author (Year)	Group	Direct Cost	Standardized Direct Cost
Khaka et al 25 (2020)	IP	£2855	$5449.00
	OP	£1781	$3399.18
Varacallo et al 18 (2018)	IP	$15 942.55 ± $5630.85	$20 510.02 ± $7244.06
	OP	$10 164.22 ± $3899.61	$13 076.22 ± $5016.83
Thangathurai et al 27 (2024)	IP	CAD$8152	$7087.87
	OP	CAD$3408	$2963.00
Pasic et al 14 (2022)	IP	$4137 ± $2285	$4566.64 ± $2522.30
	OP	$1834 ± $421	$2024.47 ± $464.72
Malik et al 13 (2020)	IP	$14 876 ± $15 987	$18 568.32 ± $19 954.98
	OP	$10 806 ± $11 823	$13 488.05 ± $14 757.47

Figure 2.

Forest plot of unstandardized mean cost difference (USDM) in US dollars (USD) comparing direct costs in the IP and OP settings for surgical management of isolated ankle fractures (random effects; 95% CI and prediction interval).

Miscellaneous Costs of Inpatient vs Outpatient Operative Isolated Ankle Fracture Management

Thangathurai et al (2024) ²⁷ examined 105 patients who underwent ORIF for isolated ankle fractures at a Canadian level 1 trauma center. In that cohort, the study-reported cost was higher for IP management than OP management, with reported values of CAD$8152 for IP cases and CAD$3408 for OP cases. They found that the median global episode-of-care cost (EOCC) for isolated ankle fracture surgeries was CAD$3487 (IQR 880) (US$2685 [IQR 616]). They also noted that the median EOCC for patients who underwent surgery within 10 days of their injury (CAD$3347 [582], US$2577 [448]) was significantly lower than the cost for patients who had their surgery delayed 10 days or more after the injury (CAD$3634 [776], US$2798 [598]) (P = .03). Malik et al (2020) ¹³ identified 5317 IPs and 6941 OPs with isolated ankle fracture undergoing ORIF in the respective settings. They found that OP management was associated with lower 90-day readmission rates (9.7% vs 14.1%; P < .001) and emergency department visits (13.8% vs 16.2%; P = .028), with study-reported 90-day economic amounts nearly $9000 lower for OP isolated ankle fractures than IP isolated ankle fractures ($12 923 vs $21 866; P < .001). Bettin et al (2019) ¹² presented cost of care data for their cohort of 61 IPs and 87 OPs undergoing ORIF for isolated ankle fractures. They found that OP management was associated with 31.6% lower costs compared with the IP pathway, also noting that obese patients had 21.6% higher costs compared with patients who were not obese. Although univariate analysis showed that facility and labor costs were 46.9% lower with OP care, no differences were seen between facility and labor costs as a percentage of totals between IP and OP care. Pasic et al (2022) ¹⁴ noted that in their cohort, OP management saw more unimalleolar isolated ankle fractures compared with IP treatment (42 [59.2%] vs 41 [32.8%], P < .001), and OPs waiting longer for surgery than IPs (9.6 days [SD 5.6 days] vs 2.0 days [SD 3.3 days], P < .001).

Safety and Complication Profile of Inpatient vs Outpatient Operative Isolated Ankle Fracture Management

Malik et al (2020) ¹³ identified 5317 IP and 6941 OP patients with isolated ankle fracture undergoing ORIF. They observed that compared with IP surgical management, the OP surgical pathway had significantly lower rates of pneumonia (2.3% vs 4.0%; P < .001), myocardial infarction (0.9% vs 1.8%; P = .005), acute renal failure (2.2% vs 5.3%; P < .001), urinary tract infections (7.4% vs 12.3%; P < .001), and pressure ulcers (0.9% vs 2.0%; P = .001), finding OP intervention as a safe and feasible option in their cohort. Similarly, Bettin et al (2019), ¹² in their cohort of 61 IPs and 87 OPs undergoing ORIF for isolated ankle fractures, found that there was no difference noted in revision surgery, readmission, or return visits to the emergency department for patients treated in either IP (0/61; zero) or OP (2/87; 2.2%) setting. Mirroring this, Pasic et al (2022) ¹⁴ found that in their cohort of 125 IPs and 71 OPs, 14 of the IPs (11.2%) presented to the emergency department or were readmitted to hospital within 30 days of discharge compared with 5 OPs (7.0%) (P = .3).

Discussion

This systematic review and meta-analysis is, to our knowledge, the first to synthesize comparative economic evidence for IP vs OP management of isolated ankle fractures. Across studies with extractable arm-level data, IP management was associated with higher standardized study-reported economic amounts than OP management; however, this pooled estimate reflects heterogeneous economic constructs rather than a uniform true-cost measure. Safety findings should also be interpreted cautiously because treatment setting was not randomized. Patients selected for OP management may have differed from IP patients in comorbidity burden, fracture complexity, functional status, and social support, which may partly explain observed differences in complications, readmissions, and emergency department utilization. This study underscores the importance of carefully selecting the appropriate setting for surgical management of isolated ankle fractures, where OP pathways can offer substantial cost savings without compromising safety, provided patients have surgically indicated fractures that are acceptably reduced and immobilized, manageable soft tissues, limited comorbidity burden, and reliable outpatient follow-up and postoperative support. Surgeons may consider OP care for eligible patients to reduce health care expenditures, but must also account for institutional constraints, such as available operating time and perioperative support, and ensure that delays in surgery or inadequate follow-up resources do not undermine patient outcomes.

There are several determinants that may contribute to the efficacy and cost burden in ankle fracture management. Resource availability, including operating room time and surgical team capacity, is a critical component of the feasibility and safety of OP care for isolated ankle fractures. Studies demonstrate that when OP pathways are supported by adequate resources such as dedicated urgent operating room slots and nursing workflows, patients can safely wait at home for surgery without an increased risk of complications or readmissions, provided they are medically appropriate candidates.^17,28,29 Implementation of such practice can help preserve IP orthopaedic resources, especially during periods of high demand or resource constraints.^28,29 Considering whether to discharge patients home or admit to the floor is a critical consideration, as it can meaningfully impact both cost-effectiveness and the recovery outcomes of patients. The current evidence consistently shows that OP ankle fracture surgery, with discharge to home, is associated with substantial cost savings—often 30% to 50% lower—compared with IP care, without evidence of higher readmission or complication rates in the available observational literature.^13,14,18,30 In fact, most patients managed as OPs are discharged home, with differences in discharge disposition primarily driven by patient comorbidities, functional status, and social factors rather than fracture characteristics alone. ³¹ IP rehabilitation is rarely required for isolated ankle fractures unless there are significant medical or social barriers to home discharge.

Additionally, time to surgery influences both clinical workflow and patient experience. Available evidence suggests that patients managed through outpatient pathways may wait longer for surgery than inpatients, but the included comparative studies did not demonstrate worse short-term outcomes or higher readmission rates when outpatient management was used in medically appropriate patients.^14,29 Rather than implying that acute inpatient intervention is inherently superior, these findings highlight the importance of reliable outpatient systems. Patients discharged for delayed outpatient fixation should have an appropriate reduction and immobilization, clear elevation and return precautions, timely clinic follow-up, and access to operative scheduling once the soft tissue envelope is suitable. Institutional outpatient pathways should therefore aim to minimize unnecessary delay while preserving safe patient selection, soft tissue monitoring, and timely definitive fixation.

Clinical Guidance for Patient Selection using Outpatient and Inpatient Care Pathways

In the available observational literature, OP management of isolated ankle fractures appears safe in appropriately selected patients and is associated with similar or lower short-term complication rates.^12-14,17 Evidence-based criteria for identifying suitable candidates for OP care include fracture type, patient comorbidities, functional status, and social support. Specifically, closed, isolated fractures (unimalleolar, bimalleolar, or trimalleolar) in the absence of open wounds, neurovascular compromise, or polytrauma are appropriate for OP management.^15,31 Furthermore, patients with low perioperative risk (eg, ASA I-II); absence of severe comorbidities such as cardiac, pulmonary, or renal conditions; and no active systemic illness are ideal candidates.^15,31 Ambulatory preinjury status and adequate social support such as reliable home care and ability to follow postoperative instructions are also key factors for OP eligibility. The current study also supports that OP management in these low-risk patients was associated with lower rates of complications such as pneumonia (2.3% vs 4.0%), myocardial infarction (0.9% vs 1.8%), acute renal failure (2.2% vs 5.3%), urinary tract infection (7.4% vs 12.3%), and pressure ulcers (0.9% vs 2.0%) within 90 days, as well as lower 90-day readmission rates (9.7% vs 14.1%) and emergency department visits (13.8% vs 16.2%) compared with IP care.^{12,14,18,28,30}

In contrast, patients with higher perioperative risk or limited ability to safely function at home should be considered for IP care or additional perioperative support. This includes patients with advanced age, poor baseline functional status, high ASA class, substantial cardiopulmonary or renal comorbidity, limited social support, or an inability to safely mobilize while maintaining non-weightbearing precautions. Even when the fracture pattern itself may be suitable for delayed outpatient fixation, patients who cannot safely transfer, ambulate with assistive devices, or comply with postoperative restrictions may require admission, therapy evaluation, or coordinated discharge planning. Injury factors that may favor IP care include polytrauma, neurovascular compromise, irreducible dislocation, severe soft tissue injury, medical instability, or need for multidisciplinary management. However, not all open fractures require prolonged admission; select low-grade open injuries treated with timely debridement, stable fixation, successful wound closure, and adequate postoperative support may be appropriate for early discharge based on surgeon judgment and institutional protocols. By adhering to these selection criteria, surgeons can balance clinical safety, outcomes at final follow-up, and cost-conscious care, ensuring that both OP and IP pathways are used appropriately based on individual patient profiles and reduce the oversaturation in either treatment system.

This study has several strengths, being the first pooled analysis to evaluate study-reported direct costs between OP and IP management of isolated ankle fractures and providing valuable insights to reinforce clinical decision making. By pooling data from multiple studies, this work offers a more robust understanding of the cost dynamics between these 2 treatment settings, which can assist surgeons and administrators in optimizing surgical pathways and reducing unnecessary health care spending.

However, there are important limitations to consider. First, the studies included in this analysis were of moderate quality, with varying methodologic approaches and patient populations. Cost definitions varied across studies and may reflect true costs, charges, or payer payments/allowed amounts, depending on whether data were derived from hospital accounting systems, administrative claims, or other sources. Although we standardized values to a common year and currency using consumer price index and purchasing power parity, these adjustments do not eliminate cross-national heterogeneity in health system structure, billing practices, payer mix, accounting methods, input prices, time horizons, or the underlying economic construct reported by each study. Therefore, our pooled estimate should be interpreted as a synthesis of reported economic burden rather than a strict comparison of activity-based costs. Additionally, although we performed a random effects meta-analysis, the heterogeneity in study designs and patient characteristics such as comorbidities and fracture types should be taken into consideration when interpretating cost differences. Finally, outpatient setting granularity was limited by the reporting of the included studies. HOPD-based care was not intentionally excluded and would have been eligible for extraction when reported; however, most studies did not distinguish ambulatory surgery centers, HOPDs, and other same-day outpatient pathways in sufficient detail to permit a separate HOPD-specific cost analysis. Furthermore, most studies relied on retrospective data or administrative claims data, which lacked granular patient-level details such as fracture severity, techniques, and postoperative care, which may influence both cost and outcome. The overall sample size was also driven largely by the 2 largest studies, which together contributed the majority of included patients. Follow-up duration in the included studies was also generally short, often ranging from 1 to 3 months. Although this gave us strong 90-day readmission data, long-term complications or revision surgeries might not have been adequately captured, potentially underestimating indirect total costs associated with care. Therefore, our pooled estimates should be interpreted with caution, and future studies should focus on prospective data collection, with a focus on standardized cost definitions and detailed, long-term outcomes, including patient-reported outcomes and return to work, activity, and sport data, with accompanying complication and revision rates. This will provide a more comprehensive understanding of the true cost-effectiveness and safety of OP and IP management of isolated ankle fractures.

Conclusion

Outpatient ORIF for isolated ankle fractures is associated with lower study-reported economic burden than inpatient management in appropriately selected patients, without clear evidence of worse short-term safety outcomes in the available comparative literature. These findings support outpatient pathways for patients with acceptable reduction and immobilization, manageable soft tissues, limited comorbidity burden, safe non-weightbearing mobility, and reliable follow-up. Because included studies used heterogeneous economic definitions and were observational, future prospective studies should use standardized economic outcomes and longer follow-up to better define the value of outpatient vs inpatient care.

Supplementary Tables

Appendix Table A.

Consumer Price Index (CPI) Indices and Inflation Factors by Country Used to Inflate Study-Reported Costs to 2025 (Local Currency).

Country	CPI (Study Year)	CPI (Target 2025)	Inflation Factor Used
United Kingdom (Khaka 2020)	108.7	139.0	1.278749
United States (Varacallo 2018)	251.107	323.048	1.286495
United States (Malik 2020)	258.811	323.048	1.2482
United States (Pasic 2022)	292.655	323.048	1.103853
Canada (Thangathurai 2024)	162.1	164.9	1.017273

Appendix Table B.

Purchasing Power Parity (PPP) Conversion Factors (Local Currency Units per International Dollar) Used to Convert 2025 Local Costs to 2025 USD.

Country	PPP
United States	1
United Kingdom	0.67
Canada	1.17