Clinical Evaluation of Hyaluronic Acid Filler for Gluteal Augmentation: A Retrospective Study

Abstract

Background:

Hyaluronic acid fillers are increasingly being used for gluteal augmentation as a minimally invasive alternative to fat grafting and silicone implants. Despite their clinical appeal, limited data exist on their efficacy and safety in buttock enhancement, and they are not yet regarded as a standard of care compared with fat grafting or implants.

Methods:

This is a retrospective observational study, reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. In this retrospective study, 26 female patients underwent gluteal augmentation with cross-linked hyaluronic acid filler at a single clinic in Seoul. Eligibility criteria included adults 20–55 years of age; the treated cohort ranged from 25 to 47 years (mean age 34.6 y). A total volume of 200–360 mL was injected subcutaneously using a 16G blunt-tip cannula, avoiding high-risk anatomical zones.

Results:

Posttreatment photographs revealed consistent improvements in gluteal projection, contour, and symmetry. The upper and superolateral buttock regions showed the most prominent enhancement. Minor, self-limited adverse events occurred in 5 patients (19.2%), including localized swelling (n = 3), ecchymosis (n = 2), and transient firmness (n = 2). No major complications such as vascular compromise,deep infection, or filler migration were observed over 6 months.

Conclusions:

Hyaluronic acid filler can be safely and effectively used for buttock augmentation, offering a nonsurgical option with immediate aesthetic benefit and a favorable safety profile.

Takeaways

Question: Can hyaluronic acid (HA) filler be used as a safe and effective nonsurgical alternative for gluteal augmentation?

Findings: In this 26-patient retrospective study, gluteal augmentation using high volumes (mean 220 mL) of HA filler injected subcutaneously with a blunt-tip cannula was performed. The procedure resulted in consistent improvements in gluteal projection and contour with no major complications. Only minor, self-limited adverse events like swelling occurred in 19.2% of patients, and satisfaction was high.

Meaning: HA filler represents a viable, minimally invasive option for buttock augmentation, providing immediate aesthetic improvement with a favorable short-term safety profile when a standardized subcutaneous technique is used.

INTRODUCTION

Interest in body contouring has grown considerably as aesthetic goals have shifted from localized facial enhancement to holistic body shaping. These procedures not only address physical appearance but are also associated with improvements in body image, self-esteem, and overall quality of life.^1–3

Among various target areas, the gluteal region has received growing academic and clinical attention due to its central role in defining body proportion and attractiveness. A number of studies have examined the ideal contours and projection and the effects of aging or weight change on buttock morphology.^4–8 In line with this growing demand, a recent global survey identified buttock augmentation as the third most frequently performed surgical body contouring procedure, with an increase of 60.9% in procedures between 2019 and 2023.⁹

In response to the growing demand for buttock enhancement, various techniques have been developed, including fat grafting, silicone implants, and injectable fillers. Among the various techniques for buttock augmentation, autologous fat grafting and silicone implants are widely used but are associated with some limitations. Fat grafting requires prior liposuction and is unsuitable for patients with low body fat or a body mass index less than 20 kg/m², as donor fat is often insufficient.¹⁰ In addition, serious complications such as fat embolism have been reported, particularly in cases involving intramuscular injection.¹⁰

Silicone implants offer an alternative for lean patients but involve surgical dissection and have been associated with complications such as wound dehiscence, implant palpability, and migration.¹¹ Given these procedural invasions and associated risks, there is growing clinical interest in fillers as a less invasive option.

Filler-based augmentation does not require liposuction or general anesthesia, can be performed in an outpatient setting under local or sedation anesthesia, and typically involves minimal recovery time. These advantages make injectable fillers an appealing alternative for patients seeking safer, faster, and more accessible gluteal enhancement.

Among various dermal fillers used for gluteal augmentation, hyaluronic acid (HA) offers distinct advantages, including reversibility, biocompatibility, and immediate volumizing effects with minimal downtime.¹² These properties make HA particularly suitable for patients seeking nonsurgical and adjustable outcomes. However, despite its growing clinical appeal, there are no established guidelines for buttock augmentation with HA fillers. Furthermore, published evidence on the efficacy and safety remains limited compared to traditional approaches such as fat grafting or implants.¹³ Accordingly, HA-based gluteal augmentation should currently be regarded as an emerging adjunctive option rather than a standard of care, reserved for carefully selected patients in whom fat grafting or implants are not suitable or desired.

Therefore, this study aimed to evaluate the clinical outcomes of gluteal augmentation using HA filler by comparing pre- and posttreatment photographs and monitoring for adverse events. In addition, the study explores injection techniques that may help maximize treatment efficacy while minimizing complications, thereby contributing to the development of safer and more effective approaches to HA-based gluteal enhancement.

METHOD

Study Design

A total of 26 female patients who underwent gluteal augmentation using HA filler at a single aesthetic clinic in Seoul, Korea, between January 2022 and June 2023, were included. Eligibility criteria permitted adults aged 20–55 years who sought nonsurgical gluteal enhancement; the treated cohort in this series ranged from 25 to 47 years (mean age 34.6 y). Each patient received a single treatment session of HA filler administered using a standardized technique. (See Video [online], which demonstrates the subcutaneous cannula-based injection technique and fan-shaped filler distribution for gluteal augmentation.)

Video 1. This video demonstrates the cannula-based, subcutaneous technique for gluteal augmentation using cross-linked hyaluronic acid filler. It shows the entry point, cannula plane above the fascia, retrograde linear threading with fan-shaped distribution, and key safety principles to avoid high-risk anatomical zones.

Download video file ^{(157.4MB, mp4)}

Eligible participants were adults 20–55 years of age who sought nonsurgical gluteal enhancement for aesthetic purposes and had adequate subcutaneous tissue volume in the gluteal region. Exclusion criteria included previous gluteal augmentation (surgical or injectable), active dermatologic disease at the injection site, bleeding disorders, autoimmune disease, pregnancy, breastfeeding, or history of allergic reaction to HA.

All patients provided written informed consent before the procedure, including consent for the use of anonymized photographs for research purposes. This study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki.

Clinical outcomes were evaluated using standardized digital photographs, a 5-point Global Aesthetic Improvement Scale (from marked worsening to marked improvement) completed independently by 2 aesthetic physicians (one of whom was not involved in performing the procedures), and simple patient satisfaction scores at baseline, 1 month, and 6 months posttreatment. Any adverse events and procedural discomfort were also recorded throughout the 6-month follow-up. Injection techniques were evaluated with particular attention to safety zones, injection depth, and filler distribution strategies. Given the exploratory nature of this small retrospective series, only descriptive statistics (means, ranges, and proportions) were calculated.

INJECTION TECHNIQUE

Gluteal augmentation was performed using a sterile, cross-linked HA filler (E.P.T.Q. EVE X; HA concentration: 24 mg/mL, no lidocaine; JETEMA Co., Ltd., Gangwon-do, Republic of Korea). Filler volume ranged from 200 to 360 mL per patient (mean: 220 mL), with individualized dosing based on gluteal morphology and augmentation goals.

Patients were positioned in the fully prone position with hips in neutral extension to optimize gluteal projection and reduce procedural risk. The superolateral quadrant of the buttock was selected as the cannula entry site, avoiding the “danger triangle” bounded by the posterior superior iliac spine, greater trochanter, and ischial tuberosity (Fig. 1).

Fig. 1.

The superolateral quadrant of the buttock was selected as the cannula entry site, avoiding the “danger triangle” bounded by the posterior superior iliac spine, greater trochanter, and ischial tuberosity.

After thorough disinfection with 2% chlorhexidine, a small skin puncture was made using an 18G surgical blade, and a 16G blunt-tip cannula (single-hole) was inserted through the incision. A tumescent solution containing 10 mg lidocaine in 10 mL normal saline per side (total 20 mg) was infiltrated into the subcutaneous plane overlying the gluteus maximus fascia. A 5-minute latency was observed to ensure adequate anesthesia and hydrodissection. No intravenous sedation was administered, and patients were monitored with standard vital-sign surveillance throughout the procedure.

HA filler was delivered in the subcutaneous fat layer, above the fascia, using a retrograde linear threading technique. The cannula was maneuvered in gentle, fan-shaped arcs at an oblique angle, maintaining consistent depth to avoid intramuscular injection. Multiple passes were made to ensure even distribution and to sculpt the gluteal silhouette.

Care was taken to avoid vascular compromise, deep muscular penetration, and overcorrection. Manual palpation during injection and visual inspection of buttock contour were used to monitor filler positioning. The cannula was removed once satisfactory augmentation was achieved, and the entry site was closed with a sterile adhesive strip.

Posttreatment care included application of cold compresses, avoidance of strenuous physical activity and prolonged direct pressure on the treated area for 48 hours, and scheduled follow-ups at 1 week, 1 month, and 6 months. Routine prophylactic antibiotics were not prescribed; oral nonopioid analgesics such as acetaminophen were permitted as needed.

RESULTS

A total of 26 patients completed the treatment and 6-month follow-up protocol. All patients underwent gluteal augmentation using HA filler following a standardized injection technique, with volumes tailored according to individual gluteal anatomy and desired aesthetic enhancement. The volume of filler administered ranged from 200 to 360 mL per patient (mean: 220 mL). Representative pre- and posttreatment photographs from four patients are shown in Figure 2 to illustrate the range of clinical outcomes.

Fig. 2.

Representative standardized photographs of four patients who underwent gluteal augmentation using cross-linked HA filler. A and B, 31-year-old woman; 100 mL per side; posttreatment at 7 days. C and D, 34-year-old woman; 130 mL per side; posttreatment at 7 days. E and F, 34-year-old woman; 110 mL per side; posttreatment at 5 days. G and H 29-year-old woman; 120 mL per side; posttreatment at 7 days. In all cases, injection was performed via multiple entry points approximately 4–6 cm superolateral to the greater trochanter, with improvement in contour and projection and no reported adverse events.

Standardized pre- and posttreatment photographs demonstrated consistent, aesthetically significant improvements in gluteal contour, projection, and lateral hip volume. Volume enhancement was most prominent in the upper and superolateral buttock regions, yielding a more rounded and lifted gluteal silhouette. In patients presenting with baseline asymmetry or lateral hip dips, strategic filler placement provided corrective effects and improved symmetry. All outcomes appeared natural, with no signs of overcorrection, surface irregularities, nodularity, or filler migration (Fig. 2).

No major complications—including vascular compromise, deep tissue infection, or sciatic nerve injury—were observed over the 6-month follow-up period. Minor adverse events occurred in 5 patients (19.2%), including localized swelling (n = 3), ecchymosis (n = 2), and transient firmness (n = 2). These events resolved within 1–3 weeks, and all responded to conservative measures such as massage and cold compress. One patient experienced delayed-onset firmness at 4 weeks postinjection, presumed related to localized capsule formation; this resolved fully following daily massage therapy over several additional weeks. On qualitative comparison of baseline, 1-month, and 6-month photographs, the evaluating physicians did not observe obvious loss of augmentation within the 6-month period.

Procedure-related discomfort was minimal. Mild, transient pain associated with cannula advancement was reported in 7 patients (26.9%), although no patient required additional anesthesia or discontinued treatment. All patients resumed normal daily activities within 24 hours, and no delayed adverse events were observed at the final follow-up. The procedure was well tolerated, with high patient satisfaction in terms of both aesthetic outcomes and recovery experience.

DISCUSSION

This clinical investigation demonstrated that HA filler can be effectively and safely used for gluteal augmentation, producing visible improvements in volume and contour symmetry. Across all cases, photographic comparison revealed consistent enhancement of upper and lateral gluteal regions, with no reports of major complications. Mild and self-limited adverse events, such as bruising and tenderness, were observed only in a minority of patients. The use of 16G blunt-tip cannulae, a purely subcutaneous injection plane, and tumescent local anesthesia likely contributed to the favorable safety and comfort profile observed in this cohort.

Findings from this study align with previous literature reporting the safety and efficacy of HA fillers for gluteal enhancement.¹³ Although HA-based gluteal augmentation is not yet a standard of care and should be considered an emerging adjunct to fat grafting and implants, it may be particularly valuable for lean patients with limited donor fat, for individuals who decline surgery or general anesthesia, and for those seeking reversible, adjustable outcomes. Compared with fat grafting, the technique avoids liposuction and operating room costs but requires purchase of relatively expensive filler and offers a finite duration of effect; current evidence suggests gradual resorption over approximately 12–24 months and a potential need for retreatment. Our overall complication rate of 19.2% (all minor, self-limited events) appears lower than many published series of fat grafting and silicone implants, which report higher rates of wound problems, contour irregularities, or more serious complications such as fat embolism, although direct comparison is limited by differences in study design and outcome measures. The injected volumes in this study (200–360 mL per patient) were lower than typical volumes reported for fat grafting, and this difference may also contribute to the favorable safety profile; however, upper safe limits for HA volume in the gluteal region remain to be defined. Although validated patient-reported outcome tools such as the BODY-Q scale were not used in this study, most patients expressed satisfaction with the posttreatment appearance, and the visual improvements were clinically evident. These observations, in conjunction with prior studies demonstrating enhanced satisfaction and body image perception following HA filler augmentation, suggest that this procedure may also offer psychosocial benefits. Future research should incorporate standardized, validated instruments such as BODY-Q to more objectively quantify patient satisfaction and quality-of-life changes.

This study has several limitations. It was conducted at a single center with a small sample size and relatively short follow-up period. In addition, no quantitative volumetric analysis or validated patient-reported outcome measures were used, and the lack of an objective comparative method limits the ability to generalize the results. Standardized lateral-view photography was not consistently obtained, and ultrasound guidance was not used to confirm the injection plane. Future studies should incorporate long-term follow-up, larger patient cohorts, and standardized outcome metrics, including volumetric imaging and satisfaction scales.

Despite these limitations, this study provides valuable insight into the practical application of HA filler for gluteal augmentation. It not only confirms the feasibility and clinical effect of HA filler in enhancing hip contour but also examines injection techniques aimed at improving safety and minimizing complications. The use of multiple anatomically safe entry points, blunt-tip cannulae, and subcutaneous injection strategy was associated with a low complication rate. Given that previous studies have emphasized the importance of individualized, anatomy-based approaches to optimize both safety and aesthetic outcomes in HA filler procedures, further investigation into standardized yet flexible techniques is warranted.¹² In our practice, HA filler is generally selected for patients who desire modest, reversible enhancement and are unsuitable or unwilling to undergo fat grafting or implants, whereas surgical options remain preferable for those requiring larger, more permanent volume changes. Future protocols may benefit from incorporating ultrasound-guided cannula placement and formal case-selection algorithms that directly compare HA fillers, fat grafting, and implants to clarify the optimal role of each modality. In this context, our findings may contribute to the development of procedural guidelines and support the establishment of safe and reproducible protocols for HA-based buttock augmentation.

CONCLUSIONS

This retrospective clinical study demonstrates that HA filler is a safe and effective option for gluteal augmentation, yielding consistent improvements in buttock volume, projection, and symmetry with minimal complications. The standardized subcutaneous injection technique using blunt-tip cannulae and anatomically safe entry points contributed to a favorable safety profile and high patient satisfaction. Given the exploratory, single-center nature of this small case series and the absence of volumetric imaging, these findings should be interpreted as preliminary. Larger-scale prospective studies with long-term follow-up and objective outcome measures are warranted to validate the role of HA filler as a minimally invasive alternative or complement to fat grafting and implants and to define optimized, reproducible protocols for HA-based gluteal enhancement in aesthetic practice.

DISCLOSURE

Jae-Young Kim is the Chairperson of company JETEMA Co., Ltd. The other authors have no financial interest to declare in relation to the content of this article.