Intraoperative Discovery of Permanent Gluteal Filler During Implant Revision: A Case Report on Surgical Adaptation and Risk Awareness

Introduction

Body contouring procedures, including gluteal augmentation, have seen an unprecedented global increase. Gluteal augmentation, including fat grafting, gluteal implants, and filler-based enhancement, has experienced a significant rise, with over 820 000 procedures reported globally in 2022, reflecting a 56.8% increase compared with the previous year [1].

Several surgical techniques have been developed for gluteal augmentation, with placement and implants that are tailored to patient anatomy, body type, and aesthetic goals. The earliest gluteal implants, introduced in the late 1960s, were placed subcutaneously, but this approach was soon abandoned due to a high rate of complications, including implant visibility, displacement, and infection [2,3]. Modern techniques have evolved to favor subfascial, intramuscular, and occasionally submuscular planes. Among these, the intramuscular technique, described by Gonzalez in 1996, remains widely used due to its natural contour and reduced palpability, particularly in slim patients [4]. Aslani et al introduced the dual-plane pocket, a novel technique placing the superior part of the implant under the gluteus medius and the inferior part intramuscularly in the gluteus maximus. In their study of 82 patients and cadaveric dissections, they demonstrated improved soft tissue coverage in the upper pole, with a low incidence of complications, such as seroma and temporary sciatic pain [5]. In recent years, hybrid techniques combining implants with autologous fat grafting have gained popularity for optimizing volume and contour, particularly in the lateral and inferior gluteal areas [6]. The choice of implant size, shape, and projection is increasingly individualized to minimize complications and improve outcomes [2].

Minimally invasive gluteal augmentation using hyaluronic acid fillers has gained increasing popularity as a safe and effective alternative to surgical procedures in appropriately selected patients. Hyaluronic acid fillers allow for controlled volume enhancement and contouring, especially in individuals seeking moderate improvements without undergoing gluteal implant placement or autologous fat transfer. When performed under sterile conditions by trained professionals, using anatomically guided techniques, hyaluronic acid-based augmentation offers predictable aesthetic outcomes, a low complication rate, and high patient satisfaction [7,8].

By contrast, the use of permanent, non-hyaluronic acid fillers, which are often administered outside of regulated medical settings, raises serious safety concerns. Products such as liquid silicone, polymethylmethacrylate, and polyacrylamide hydrogel have been used illicitly for gluteal enhancement, particularly by non-medical personnel operating in non-clinical environments. These unauthorized procedures have been linked to severe complications, including chronic granulomatous inflammation, filler migration, tissue necrosis, and pulmonary embolism [9–11]. Health authorities, including the U.S. Food and Drug Administration, have issued multiple warnings, but the lack of regulation in many countries continues to allow these risky practices to proliferate [12].

Case Report

A 29-year-old woman in good health presented for a consultation regarding the aesthetic appearance of her buttocks, which she found unsatisfactory (Figure 1). She had undergone a previous buttock augmentation with silicone implants 3 years earlier in another country. No surgical records were available, and the patient was unable to provide basic information about the procedure, including the type, size, or plane of implant placement. On clinical examination, the implants were highly mobile, palpated in the subcutaneous plane, without associated pain. The overlying skin was normal, with no signs of redness, induration, or inflammation. The surgical scars were mature, hypopigmented, and notably wide (Figure 2). The patient expressed a desire for greater upper-pole projection and a more defined hourglass silhouette.

The treatment plan established during the consultation included implant exchange with repositioning into an intramuscular pocket, combined with liposuction of the lower back, fat transfer to the hip area, and scar revision.

The procedure began with infiltration of the lower back for liposuction. Upon the initial incision, a thick, gel-like substance was released. The assisting nurse immediately identified it as a permanent filler (Video 1).

Manual extraction consisted of external compression and digital pressure applied around the incision sites, allowing extrusion of the gel-like filler material. This was combined with gentle curettage of the subcutaneous tissue and repeated saline-povidone irrigation to evacuate as much foreign material as possible.

Liposuction of the lower back was completed without difficulty using the MicroAir device with a 4-mm cannula. The unexpected presence of filler was confined to the subcutaneous tissue of the buttocks, lateral regions, and infragluteal fold. Given the infiltration and tissue compromise in these areas, fat grafting was abandoned to reduce the risk of infection and ensure graft viability. The procedure was then continued with implant exchange.

The second step involved implant exchange. The existing intergluteal scar was excised, and bilateral dissection was performed. The subcutaneous implants were easily identified and removed (Figure 3). Intramuscular pockets were then created using blunt dissection with an elevator, followed by irrigation and hemostasis (Figure 4). After a new skin antisepsis and glove change, new 410-cc biconvex gluteal smooth surface implants (Sebbin) were inserted into the intramuscular pockets. No drains were placed. Closure was performed in layers, with a musculo-fascia suture, followed by subcutaneous and skin closure. The postoperative course was uneventful, and the patient was discharged on postoperative day 2.

The aesthetic result was assessed 3 months postoperatively and demonstrated improved upper pole projection and enhanced contour without implant visibility. The patient was satisfied with the outcome (Figure 1).

This case highlights the complex management of gluteal augmentation revision in the context of previously placed subcutaneous implants and undocumented permanent filler injections. The widespread popularity of gluteal contouring procedures has led to an increase in regulated and unregulated interventions, with patients often presenting years later for revision surgery without access to operative reports or knowledge of the materials used.

Discussion

Subcutaneous implant placement, while technically simpler than other techniques, is known to have a higher risk of complications such as implant displacement, visibility, and poor contour, especially in slim patients. This approach has largely been replaced by the intramuscular technique, which offers superior soft tissue coverage, implant stability, and more natural aesthetic outcomes [4]. In this case, the decision to reposition the implants into an intramuscular pocket was made to improve projection, correct the sagging appearance of the buttocks, and reduce implant mobility.

An unexpected intraoperative finding was the presence of permanent filler material throughout the subcutaneous plane of the lower back, hips, and infra-gluteal region. These substances, most likely silicone or polyacrylamide hydrogel, are frequently used by unlicensed providers and are associated with significant risks, including migration, granulomatous inflammation, infection, and even fatal embolic events [9,13]. Even after partial extraction, residual permanent filler remains a source of long-term morbidity. Reported complications extend beyond the immediate postoperative period and can include progressive contour deformities, recurrent or delayed infections, chronic inflammatory reactions leading to fibrosis, and late-onset tissue necrosis [14].

In complex cases, preoperative imaging, such as ultrasound or magnetic resonance imaging, can provide valuable information, particularly in patients with a history of undocumented procedures abroad. Such investigations can help detect foreign materials or abnormal tissue changes, allowing the surgeon to anticipate intraoperative challenges. In the present case, however, the patient never reported any filler injection and there were no clinical signs suggestive of this history, which limited the indication for preoperative imaging.

Postoperatively, long-term surveillance remains essential. Clinical monitoring should include regular assessment for induration, erythema, pain, or contour changes, with imaging as a consideration if symptoms develop. Patients must also be counseled regarding the possibility of delayed complications and the potential need for future surgical intervention.

The detection of complications in the present case altered the surgical plan by eliminating fat grafting, due to the presence of tissue undermining and devascularization in the injected area, which increased the risk of infection and reduced the likelihood of fat graft survival.

Conclusions

This case shows the critical need for comprehensive preoperative evaluation, informed patient counseling on safe augmentation options, and surgical adaptability when faced with unexpected intraoperative findings. Achieving a satisfactory aesthetic outcome despite significant challenges underscores the importance of adhering to evidence-based techniques and reinforces the urgent need for stricter regulation of non-medical filler practices to protect patient safety.