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Article

Impact of BMI on Complications, Readmissions, and Perioperative Metrics in a Mature Direct Anterior Approach Total Hip Arthroplasty (THA) Practice

by
Stefan W. Fleps
* and
Christopher J. Drinkwater
Department of Orthopaedics and Physical Performance, University of Rochester, Miracle Mile Drive, Rochester, NY 14623, USA
*
Author to whom correspondence should be addressed.
Complications 2025, 2(4), 27; https://doi.org/10.3390/complications2040027
Submission received: 24 August 2025 / Revised: 15 October 2025 / Accepted: 28 October 2025 / Published: 3 November 2025
Review Reports Versions Notes

Abstract

This study analyzed complication rates, perioperative metrics, and hospital readmissions across BMI cohorts in patients undergoing direct anterior approach (DAA) total hip arthroplasty (THA) in a mature hip practice. Currently, the precise BMI cutoff points for risk in THA are not fully understood. A retrospective review was conducted of patients who underwent DAA THA by a single, highly experienced, fellowship-trained surgeon between January 2021 and January 2023. The use of single-surgeon cases allows for control of many potentially confounding variables but may limit the generalizability of the findings. Data collected included patient demographics, hospital readmissions, 12-month complication rates, and intraoperative metrics. Patients with Class II obesity (BMI 35–39.9) kg/m2 and Class I obesity (BMI 30–34.9) kg/m2 had significantly higher intraoperative blood loss and longer operative times compared to the control group (BMI 20–24.9 kg/m2). No statistically significant differences in hospital readmission rates or complication rates were observed between BMI cohorts. Higher BMI was associated with increased intraoperative blood loss and longer operation time; however, no differences were found in hospital readmissions or complication rates between BMI cohorts.

1. Introduction

Obesity rates have been rising dramatically, with projections indicating that by 2050 two thirds of adults in the United States will be classified as obese [1]. Obesity has been associated with both the early development and progression of hip osteoarthritis [2,3]. For patients with end-stage osteoarthritis, total hip arthroplasty (THA) is the primary surgical intervention. Between 2000 and 2019, the annual volume of THA increased by approximately 177%, and this trend is projected to continue [4]. Within THA, the direct anterior approach (DAA) has become increasingly popular [5]. Given the rising prevalence of obesity, the growth in THA utilization, and the socioeconomic burden of an aging population, it is essential to understand how obesity impacts DAA THA outcomes.
Previous research has identified obesity as a risk factor for complications following THA [6,7,8,9]. Interestingly, some studies have reported no differences in dislocation rates or risk of revision for instability among different BMI cohorts [10]. Meta-analyses have shown higher complication rates in patients with higher BMIs, although some studies have found no association [11]. Only a few studies have specifically examined the impact of obesity on complications in DAA THA, and their findings have been inconsistent, with some reporting increased complication rates and others finding no difference [12,13,14]. Many of these studies group patients simply above or below a certain BMI cutoff, limiting the understanding of whether complications, hospital readmissions, and perioperative parameters scale with BMI. Furthermore, these studies often differ in the types of complications reported, surgical approach, surgeon experience, and geographic location. While large database studies offer the advantage of sample size, they may introduce confounding variables that limit interpretation. To address these gaps in the literature this study utilized multiple BMI cohorts undergoing DAA THA in a mature hip practice.
There is currently no consensus on complication rates, types, readmission rates, or perioperative parameters in obese patients undergoing DAA THA. This study aimed to minimize confounding variables by analyzing consecutive DAA THA cases performed by a single, highly experienced surgeon at a single institution. We compared complication rates, types, readmission rates, and perioperative metrics across different BMI cohorts in patients undergoing DAA THA in a mature hip practice.

2. Materials and Methods

A retrospective chart review was conducted on adult patients aged 18 to 85 years with a body mass index (BMI) between 20 kg/m2 and 39.9 kg/m2 who underwent direct anterior approach (DAA) total hip arthroplasty (THA). All procedures were performed between January 2021 and January 2023 at a single surgical site by the senior author, who had performed over 2000 DAA cases prior to the study period, thereby exceeding the learning curve. This study received approval from the University of Rochester Office for Human Subjects Research on 26 February 2025 (Study ID: STUDY00010189).
Exclusion criteria included patients younger than 18 or older than 85 years, a BMI of less than 20 kg/m2, a BMI of greater than 39.9 kg/m2, revision THA, conversion of prior hip procedures to THA, and procedures performed at an outside healthcare system.
Demographic data collected from patient charts included age, sex, BMI, and American Society of Anesthesiologists (ASA) classification. Patients were categorized into BMI-based cohorts based on the Centers for Disease Control and Prevention (CDC) classifications at the time of surgery. The control group consisted of patients in a BMI range 20–24.9 kg/m2. The additional cohorts were overweight (BMI of 25–29.9 kg/m2), Class I obesity (30–34.9 kg/m2), and Class II obesity (35–39.9 kg/m2). A total of 479 cases were included and there were 55 Class II obesity patients,142 patients with Class I obesity, 197 patients in the overweight category, and 85 patients with a BMI of 20–24.99 kg/m2.
Perioperative data collected included length of hospital stay, operative time, estimated blood loss, and postoperative catheterization status. Hospital readmission rates were assessed through manual chart review at 1 week, 3 weeks, and 90 days postoperatively.
Complications were identified through manual chart review up to 12 months postoperatively and included both intraoperative and postoperative events. Major complications included dislocations, dislocations in the post anesthesia recovery unit (PACU), superficial and deep infections, periprosthetic fracture, major nerve palsy, and deep vein thrombosis (DVT). Superficial infections were defined as those limited to the skin or subcutaneous tissue that were documented or required clinical follow-up. Deep infections were defined as infections involving the prosthesis and extending to the muscle or deep fascia. DVTs were identified using relevant International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes, I82.X, as well as confirmed chart documentation of a DVT diagnosis. PACU dislocations were defined as dislocations of the operative hip occurring within minutes to hours after surgery while patients were recovering from anesthesia.

2.1. Statistical Analysis

All data were analyzed using Microsoft Excel (version 16.96.1) and GraphPad Prism (version 10.4.1) software. Normality of continuous variables was assessed using the Shapiro–Wilk test. Normally distributed continuous variables were compared using unpaired t-tests. Non-normally distributed continuous variables were analyzed using Mann–Whitney U tests. Categorical data were compared using Chi-Square tests. A p-value of <0.05 was considered statistically significant.

2.2. Surgical Procedure

Standard direct anterior approach THA was performed for all patients. All cases were performed with the patient supine using the Hana operating table (Mizuho OSI, Union City, CA, USA). Patients received perioperative antibiotics and 1000 mg of Tranexamic Acid intraoperatively. Fluoroscopy was used to assess component position intraoperatively. Additionally, patients received standard deep vein thrombosis prophylaxis.

3. Results

Table 1 summarizes the patient demographics for all study participants. The control group (BMI = 20–24.9 kg/m2) included 85 patients with a mean age of 66.91 years, which was significantly higher than the Class II obesity group (n = 55) with a mean age of 62.44 (p < 0.01). The Class I obesity group and the overweight group had a significantly higher proportion of male patients compared to the control group (p = 0.0019 and 0.0028, respectively). Regarding ASA classification, the Class II obesity group had significantly fewer patients classified as ASA Class II and significantly more patients classified as ASA Class III relative to the control group. Similarly, the Class I obesity group had significantly fewer patients with ASA Class II designation and significantly more with a Class III designation relative to the control group. Both the Class II obesity and the Class I obesity group also had significantly higher mean BMIs than the control group. In the overweight group (n = 197), there was a significantly higher proportion of males, and a significantly higher mean BMI compared to the control group. No other comparisons between the experimental groups and the control group reached statistical significance.
The perioperative metrics recorded in this study are presented in Table 2. There was a non-significant trend toward shorter length of stay in lower BMI cohorts compared to higher BMI cohorts. Same-day discharge rates were significantly higher in the control cohort (7.1%) compared to the Class I obesity cohort (0.7%, p = 0.0074). Operative time increased with higher BMI. The Class II obesity cohort had a mean operative time of 73.00 min, significantly longer than the control cohort at 62.58 min (p < 0.01). The Class I obesity cohort had a mean operative time of 67.81 min, also significantly longer than the control group (p < 0.01). Estimated blood loss (EBL) was significantly higher in higher BMI groups. The Class II obesity cohort had a mean EBL of 370.02 mL, significantly higher than 271.29 mL in the control group (p < 0.01). The Class I obesity cohort had a mean EBL of 298.77 mL, also significantly higher than the control group (p = 0.0206). Additionally, 69.1% of the patients in the Class II obesity cohort had an EBL > 300 mL compared to 24.7% of the control group (p < 0.01). There were no statistically significant differences between the overweight and the control group in any perioperative metrics. There were also no significant differences between any BMI group and the control cohort regarding postoperative catheterization.
Table 3 summarizes the hospital readmission rates for each BMI cohort compared to the control group. There were no significant differences in hospital readmissions across all cohorts in the 1-week, 3-week, and 90-day periods following surgery. Additionally, no cohort has a significantly higher rate of total hospital readmissions within 90 days postoperatively compared to the control group.
Table 4 summarizes the complication rates across the BMI cohorts compared to the control group. There were four post operative dislocations that did not occur in the PACU: one in the control group and three in the overweight group; however, this difference was not statistically significant. There were two dislocations that occurred in the PACU: one in the control group and one in the overweight group, with no statistically significant differences between the experimental groups and the control group. Within the study population, there were three superficial infections, with one occurring in each of the Class II obesity, Class I obesity, and overweight groups; there was no significant difference between any of these groups and the control group. No deep infections occurred in the study population. A total of four periprosthetic fractures were reported, with two occurring in the Class I obesity group and two in the overweight group, and this was not statistically different from the control group. One deep vein thrombosis (DVT) occurred in the control group, and one occurred in the overweight group, with no significant differences in DVT rates compared to the control group. There was a single case of nerve injury in the Class II obesity group, but this was not statistically higher than the control group. Overall, there were no statistically significant differences in complication rates when comparing any of the BMI groups to the control group.
Table 5 presents the overall complication rates among the 479 cases of DAA THA in this study. The non-PACU dislocation rate was 0.8%, and the PACU dislocation rate was 0.4%. Superficial infections occurred in 0.6% of patients. Periprosthetic fractures were reported in 0.8% of patients. The rate of DVT was 0.4%, and the rate of nerve injury was 0.2%. Overall, the total complication rate of any type from DAA THA in this study was 3.3%.

4. Discussion

This study evaluated perioperative metrics, hospital readmissions, and complications in 479 consecutive patients undergoing DAA THA. Patients were stratified into four groups based on BMI at the time of surgery: 20–24.9 kg/m2 (control), 25–29.9 kg/m2 (overweight), 30–34.9 kg/m2 (Class I obesity), 35–39.9 kg/m2 (Class II obesity). The Class II obesity group had a significantly lower average age and a higher proportion of ASA Class III patients, as well as increased estimated intraoperative blood loss and longer operative times compared to the control group.
Prior research has shown that obesity contributes to accelerated hip osteoarthritis (OA) and earlier need for THA [15,16,17]. Therefore, the younger age in the highest BMI cohort likely reflects the earlier progression of OA. Our findings are consistent with the existing literature, which has repeatedly demonstrated that patients with higher BMIs experience greater intraoperative blood loss during THA [18,19]. Similarly, the longer operative times in the Class II obesity group are supported by previous studies indicating increased surgical times in obese patients undergoing THA [20,21,22]. Importantly all patients in this study underwent surgery using the same preoperative and intraoperative protocols, and all procedures were performed by a single, highly experienced surgeon at a single institution. This consistency minimizes potential confounding variables and strengthens the finding that higher BMI is associated with increased intraoperative blood loss and longer operative time in THA.
The Class I obesity group had a significantly higher proportion of male patients and a greater proportion of ASA Class III patients compared to the control group. Operative time and estimated blood loss in this group were greater than the control group and less than in the Class II obesity group. Longer operative times in THA have been associated with an increased risk of medical morbidity and postoperative complications [23,24]. Further research should report on operative times in obese patients undergoing DAA THA as it is a pertinent variable related to outcome and cost. These findings further emphasize the direct relationship between higher BMI, and both increased operative time and intraoperative blood loss.
The overweight group had a significantly higher proportion of male patients compared to the control group, likely reflecting underlying biological factors. However, there were no significant differences in estimated blood loss, operative time, or same-day discharge rates between this group and the control cohort. A recent study reported no statistically significant differences in mean operative time or blood loss between BMI cohorts of 18.50–24.99 kg/m2 and 25–29.99 kg/m2, which aligns with our findings [25]. Similarly, an earlier study found that patients with a BMI of 26–30 kg/m2 did not have increased intraoperative blood loss compared to those with a BMI below 26 kg/m2 [26]. These studies included THA cases performed via a direct lateral approach and posterior approach which may introduce variability when comparing to the DAA. These results support the existing literature indicating that patients in the overweight BMI category do not experience increased operative time or blood loss during THA.
Our study found no significant differences in readmission rates among BMI cohorts at 1-week, 3-week, and 90-day intervals following DAA THA. A recent report by Simpson et al. identified a significant increase in 30-day admissions in class III obesity patients (BMI > 40) following DAA THA compared to lower BMI classes, though no significant differences were observed between other BMI cohorts [26]. Previous studies have suggested that elevated BMI is a risk factor for higher readmission rates following THA [27,28], while more recent analyses have found no such association [29]. Many of these prior studies draw from large datasets that include multiple surgical centers, geographic regions, and patient populations. These factors can introduce variability into their findings. The consecutive nature of the surgeries and the standardized discharge protocols at a single surgical center in our study enhance the reliability of our findings, suggesting that BMI within a range of 20–39.9 kg/m2 may not influence readmission rates following DAA THA. Nevertheless, further research with larger sample sizes is warranted to validate these results.
Our study found no significant differences in complication types across the BMI cohorts. The current literature remains heterogenous regarding dislocation rates following DAA THA in relation to BMI [10,30,31]. Many of these studies employ broader or inconsistent BMI categories and may be confounded by comorbidities commonly associated with increased BMI. While our study grouped patients with a BMI 35–39.9 kg/m2 into a single category, other studies have used higher cutoffs, such as 40 kg/m2 or even 50 kg/m2 which may contribute to the variation in reported dislocation rates. In our study of 479 cases there were only four non-PACU dislocation events (0.8%), which is on the lower end of the 1–3% range typically cited in the literature [30,32,33]. This low dislocation rate may reflect the experience of a mature hip practice. Additionally, the overall low incidence of complications and relatively small sample sizes in both the control and Class II obesity groups may have limited the ability to detect statistically significant differences in dislocation rates.
Superficial wound infections have been associated with increased BMI in patients undergoing DAA THA in several studies [34,35]. However, this finding is not universal across the literature, as some studies have found no increased infection risk related to BMI following THA [10,33]. In our study, no deep infections were observed, and only three cases superficial infection occurred. Purcell et al. grouped DAA THA patients into BMI < 35 kg/m2 and ≥35 kg/m2, reporting a significantly higher rate of deep infections in the BMI ≥ 35 kg/m2 group, though they found no significant difference in superficial wound dehiscence [14]. A recent long-term study examining periprosthetic joint infection up to 15 years post THA found that patients with class III and IV obesity had a threefold and ninefold increased risk of infection, respectively [36]. The lack of statistically significant differences in our study may be due to unequal sample sizes across BMI cohorts or the low overall infection incidence in a mature, high-volume DAA THA practice.
We also collected data on periprosthetic fractures, deep vein thrombosis (DVT), and nerve injuries occurring within 12 months following DAA THA. Multiple studies have reported no increased risk of periprosthetic fracture based on BMI in THA [13,37,38], and our findings are consistent with this literature. Similarly, a large-scale database study found no significant difference in DVT risk across BMI categories in THA patients [39]. In our study, only two cases of DVT were identified, limiting our ability to detect statistically significant differences between BMI cohorts. Larger studies are needed to clarify whether BMI influences DVT incidence, with appropriate control for confounding variables.
Regarding nerve injury, there was a single case of major nerve injury in the Class II obesity cohort. Major nerve injury is a rare complication following THA, with reported rates around 0.35% [40]. Our observed rate of 0.2% is consistent with these figures. Given the low incidence and study’s sample size of 479 cases, the power to detect significant differences in nerve injury rates between BMI cohorts is limited.
In future work, we plan to evaluate complications of DAA THA in patients with Class III obesity. Currently, no consensus exists on a BMI threshold at which the risks of THA outweigh potential benefits. To address this, a larger cohort including a substantial number of patients in this high BMI category would allow for a more robust assessment of perioperative risk. We also plan to incorporate relevant comorbidities such as diabetes mellitus, diagnosed hypertension, chronic kidney disease, and anemia alongside ASA classification could enable a more precise evaluation of how BMI interacts with underlying health status to influence surgical outcomes.
Another long-term goal of our group is to extend follow-up beyond the initial postoperative year to evaluate how early complications influence long-term survivorship and overall functional outcomes. Incorporating patient-reported satisfaction measures will also be a key focus, allowing us to assess whether long-term satisfaction and perceived success differ across BMI categories.
In this study, we attempted to control for potential risk factors that may coincide with BMI by adjusting for age, sex, and ASA classification at the time of surgery. The ASA classification system encompasses a wide range of systemic diseases including hypertension, diabetes mellitus, chronic obstructive pulmonary disease, and anemia. This approach provides a general assessment of a patient’s overall medical status and reflects the cumulative burden and management of chronic disease at the time of surgery.
However, the use of BMI remains an imperfect metric for body composition, as it does not distinguish between fat-free mass and adipose tissue. Future studies may seek to incorporate direct measures of body composition to better assess surgical risk.
Additionally, hospital readmission rates and complications in this study were based on documentation within the electronic medical record. While most healthcare systems, clinics, and hospitals in our network participate in record sharing, some follow-up events may have been missed if patients sought care at outside institutions. Major complications, which typically require hospital management, were likely captured; however, the potential for underreporting cannot be completely excluded.
This study has several limitations. First, its retrospective design which relies on the accuracy of prior documentation and does not allow for matched subject allocation across BMI groups. Second, BMI is an imperfect metric for patient stratification, as it does not differentiate between fat and muscle mass or account for other relevant anthropometric variables. Additionally, the study did not control for comorbidities that may correlate with or influence BMI. Patients were grouped into BMI intervals of 5 kg/m2, and individuals with a BMI below 20 kg/m2 were not assessed. Due to sample size constraints, our highest BMI cohort included all patients with a BMI of 35–39.9 kg/m2. Further studies with larger cohorts should stratify higher BMI categories (>40 kg/m2) to detect potential differences in outcomes more precisely. Leg length discrepancy (LLD) was not analyzed in detail, although no patients required treatment for LLD in the 12 months postoperatively. Lastly, this study was limited to DAA THA procedures performed by a single, experienced surgeon at a single surgical center. While this minimizes confounding variables, it may limit the generalizability of the findings to other surgeons, institutions, or healthcare systems.

5. Conclusions

Patients with Class II obesity and Class I obesity undergoing DAA THA were associated with significantly increased intraoperative blood loss and longer operative times. In contrast, patients in the overweight BMI group (25–29.9 kg/m2) showed no statistically significant differences from the normal weight group in any measured outcomes. BMI did not influence hospital readmission rates. Overall, complication rates were low across all cohorts, with no significant differences in complication rates or types based on BMI. These findings support the feasibility of performing DAA THA in patients with higher BMI, though certain perioperative challenges may be more prevalent. Future research should focus on identifying specific BMI thresholds associated with increased risk and developing effective strategies for minimizing risk and optimizing outcomes in these populations.

Author Contributions

S.W.F.: Conceptualization, Formal Analysis, Investigation, Writing—Original and Draft, Writing—Review and Editing. C.J.D.: Conceptualization, Methodology, Resources, Writing—Original and Draft, Writing—Review and Editing, Supervision. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

The study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of the University of Rochester. (Study ID: STUDY00010189, date: 26 February 2025).

Informed Consent Statement

The study received a patient informed consent exemption from the University of Rochester Office for Human Subject Protection on 26 February 2025. Patient consent was waived due to this study receiving exemption from our institutional review board as it was deemed unnecessary.

Data Availability Statement

The data of this study are available in the article itself. Due to patient confidentiality the data are not publicly available.

Conflicts of Interest

Christopher Drinkwater paid consultant for DePuy Synthes, no additional conflicting interests.

Abbreviations

The following abbreviations are used in this manuscript:
THATotal Hip Arthroplasty
DAADirect Anterior Approach
BMIBody Mass Index
ASAAmerican Society of Anesthesiologists
ICD-10-CMInternational Classification of Diseases, 10th Revision, Clinical Modification

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Table 1. Patient Demographics.
Table 1. Patient Demographics.
BMI GroupnAge% Male
N (%)		ASA Class I
N (%)		ASA Class II
N (%)		ASA Class III
N (%)		Mean BMI
(kg/m2)
Class II Obesity5562.44 ± 7.5021 (38.2)0 (0)24 (43.6)31 (56.4)37.08 ± 1.84
Control8566.91 ± 11.0728 (32.9)1 (1.8)61 (71.8)23 (27.1)23.20 ± 1.27
p-value <0.0001 *0.530.360.0009 *0.0005 *<0.0001 *
Class I Obesity14265.53 ± 9.1577 (54.2)1 (0.7)78 (54.9)63 (44.4)32.05 ± 1.38
Control8566.91 ± 11.0728 (32.9)1 (1.8)61 (71.8)23 (27.1)23.20 ± 1.27
p-value 0.0850.0019 *0.710.0117 *0.0093 *<0.0001 *
Overweight19766.84 ± 9.52103 (52.2)1 (0.5)123 (62.4)73 (37.1)27.41 ± 1.58
Control8566.91 ± 11.0728 (32.9)1 (1.8)61 (71.8)23 (27.1)23.20 ± 1.27
p-value 0.66520.0028 *0.53910.14450.0982<0.0001 *
Age and Body Mass Index (BMI) are presented as mean ± S.D. * denotes p-value < 0.05.
Table 2. Perioperative Surgical Data between BMI Cohorts.
Table 2. Perioperative Surgical Data between BMI Cohorts.
BMI GroupNLength of Stay
(Days)		Same Day Discharge
N (%)		Operative Time
(min)		Estimated Blood Loss
(mL)		Cases > 300 mL Blood Loss
N (%)		Catheterization
N (%)
Class II Obesity551.33 ± 1.072 (2.9)73.00 ± 15.82370.02 ± 187.1938 (69.1)5 (9.1)
Control851.15 ± 0.846 (7.1)62.58 ± 14.19271.29 ± 203.1521 (24.7)13 (15.3)
p-value 0.360.23<0.0001 *<0.0001 *<0.0001 *0.28
Class I Obesity1421.18 ± 0.791 (0.7)67.81 ± 12.47298.77 ± 165.7945 (31.7)12 (8.5)
Control851.15 ± 0.846 (7.1)62.58 ± 14.19271.29 ± 203.1521 (24.7)13 (15.3)
p-value 0.590.0074 *0.0007 *0.0206 *0.260.11
Overweight1971.10 ± 0.813 (6.6)64.40 ± 12.41264.64 ± 130.3242 (21.3)17 (8.6)
Control851.15 ± 0.846 (7.1)62.58 ± 14.19271.29 ± 203.1521 (24.7)13 (15.3)
p-value 0.380.890.130.310.530.10
Length of stay, operative time, estimated blood loss are presented as mean ± S.D. * denotes p-value < 0.05.
Table 3. Temporal Readmission Rates by BMI Cohort.
Table 3. Temporal Readmission Rates by BMI Cohort.
BMI GroupN1-Week
N (%)		3-Week
N (%)		90-Day
N (%)		Total
N (%)
Class II Obesity551 (1.8)0 (0)1 (1.8)2 (3.6)
Control850 (0)0 (0)2 (2.4)2 (2.4)
p-value 0.211.00.830.84
Class I Obesity1420 (0)1 (0.7)2 (1.4)3 (2.1)
Control850 (0)0 (0)2 (2.4)2 (2.4)
p-value 1.00.440.600.91
Overweight1972 (1.0)5 (2.5)4 (2.0)11 (5.6)
Control850 (0)0 (0)2 (2.4)2 (2.4)
p-value 0.350.140.860.24
Values are presented as number of participants and percentage of cohorts.
Table 4. Complication Rates by BMI Cohort.
Table 4. Complication Rates by BMI Cohort.
BMI GroupNDislocations
N (%)		PACU Dislocations
N (%)		Superficial Infection
N (%)		Deep Infection
N (%)		Periprosthetic Fracture
N (%)		DVT
N (%)		Nerve Injury
N (%)		Total
N (%)
Class II Obesity550 (0)0 (0)1 (1.9)0 (0)0 (0)0 (0)1 (1.9)2 (3.6)
Control851 (1.2)1 (1.2)0 (0)0 (0)0 (0)1 (1.2)0 (0)3 (3.5)
p-value 0.420.420.211.01.00.420.210.97
Class I Obesity1420 (0)0 (0)1 (0.7)0 (0)2 (1.4)0 (0)0 (0)4 (2.8)
Control851 (1.2)1 (1.2)0 (0)0 (0)0 (0)1 (1.2)0 (0)3 (3.5)
p-value 0.200.200.441.00.270.201.00.76
Overweight1973 (1.5)1 (0.5)1 (0.5)0 (0)2 (1.0)1 (0.5)0 (0)8 (4.1)
Control851 (1.2)1 (1.2)0 (0)0 (0)0 (0)1 (1.2)0 (0)3 (3.5)
p-value 0.820.540.511.00.350.541.00.83
Values are presented as number of participants and percentage of cohorts. Deep Vein Thrombosis (DVT), Post-Anesthesia Care Unit (PACU).
Table 5. Overall Complication Rates.
Table 5. Overall Complication Rates.
Dislocations
N (%)		PACU Dislocations
N (%)		Superficial Infection
N (%)		Deep Infection
N (%)		Periprosthetic Fracture
N (%)		DVT
N (%)		Nerve Injury
N (%)		Total
N (%)
Total
N = 479		4 (0.8)2 (0.4)3 (0.6)0 (0)4 (0.8)2 (0.4)1 (0.2)16 (3.3)
Values are presented as number of participants and percentage.
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Fleps, S.W.; Drinkwater, C.J. Impact of BMI on Complications, Readmissions, and Perioperative Metrics in a Mature Direct Anterior Approach Total Hip Arthroplasty (THA) Practice. Complications 2025, 2, 27. https://doi.org/10.3390/complications2040027

AMA Style

Fleps SW, Drinkwater CJ. Impact of BMI on Complications, Readmissions, and Perioperative Metrics in a Mature Direct Anterior Approach Total Hip Arthroplasty (THA) Practice. Complications. 2025; 2(4):27. https://doi.org/10.3390/complications2040027

Chicago/Turabian Style

Fleps, Stefan W., and Christopher J. Drinkwater. 2025. "Impact of BMI on Complications, Readmissions, and Perioperative Metrics in a Mature Direct Anterior Approach Total Hip Arthroplasty (THA) Practice" Complications 2, no. 4: 27. https://doi.org/10.3390/complications2040027

APA Style

Fleps, S. W., & Drinkwater, C. J. (2025). Impact of BMI on Complications, Readmissions, and Perioperative Metrics in a Mature Direct Anterior Approach Total Hip Arthroplasty (THA) Practice. Complications, 2(4), 27. https://doi.org/10.3390/complications2040027

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