B-ultrasound-assisted gluteal fat grafting in Asians: A prospective study of quantitative results from three-dimensional imaging and B-ultrasound analysis.

BACKGROUND: The increasing number of fatalities caused by gluteal fat grafting is concerning; thus, there is a need to determine ways to obtain the ideal aesthetic effect while ensuring a safe operation. In this study, three-dimensional (3D) measurements combined with B-ultrasound were used to evaluate the effect of gluteal fat augmentation in Asians, whose safety and effectiveness were confirmed using quantitative data. METHODS: Thirty-five consecutive female patients were evaluated in this prospective clinical study. All patients underwent B-ultrasound-assisted gluteal fat augmentation on the subcutaneous plane alone. 3D imaging and B-ultrasound analysis of the adipose tissue thickness in the gluteal region were performed preoperatively and at 1 week, 3 months and 6 months post-operatively. RESULTS: The waist circumference of the patients decreased, gluteal circumference and length of the gluteal crease increased and average waist-to-hip ratio improved from 0.78 to 0.74. At 3 months and 6 months post-operatively, the adipose tissue thickness decreased by 5.1% and 15.1%, respectively. The fat retention rates calculated using 3D imaging measurements at 3 months and 6 months post-operatively were 77.9% and 64.7%, respectively. According to the BODY-Q scale scores, patients reported a high level of satisfaction post-operatively. CONCLUSIONS: B-ultrasound guidance can effectively prevent the occurrence of fatal fat embolism during gluteal fat grafting and maximise the augmentation effect. The quantitative data obtained using 3D measurements and B-ultrasound confirmed the safety and effectiveness of fat injections for gluteal augmentation under B-ultrasound guidance.

Danger Zones of the Gluteal Anatomy: Improving the Safety Profile of the Gluteal Fat Grafting.

INTRODUCTION: Knowledge of the vascular anatomy is critical to performing safe gluteal surgery. To date, only the course of the main blood vessels within the muscles has been outlined. These findings are based on MRI and CTA images that do not conform to a topographically standardized and normalized probability distribution. OBJECTIVES: The aim of this study was to develop a three-dimensional mapping of the gluteal zones of high vascular density in relation to anatomical landmarks. MATERIALS AND METHODS: This single-center retrospective cohort analysis comprised all consecutive patients who underwent cone-beam computed tomography (CBCT) scans between January 2016 and October 2021. The location of blood vessels in the gluteal region was allometrically normalized in relation to anatomical landmarks. Moreover, the caliber and area of the blood vessels were assessed. RESULTS: CBCT scans of 32 patients with an average age of 64 ± 12 years (range 34-87 years) were included. Fifty-three percent were female. The median [IQR] caliber of the intramuscular gluteal vessels was 1.47 [1.15-1.88] mm, significantly greater than that of the subcutaneous vessels 1.09 [0.72-1.44] mm (p < 0.001). Vascular density was higher intramuscularly, as 4.5% of the area of the muscle was occupied by blood vessels, as opposed to 0.3% in the adipose tissue. CONCLUSION: The analysis of the CBCT scans showed a higher vascular density and larger vessels intramuscularly. We, therefore, recommend the injection of autologous fat merely to the subcutaneous plane. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Correlation between preoperative CT scan of the paraspinal, psoas, and gluteus muscles and postoperative ambulatory status in patients with femoral neck fractures.

BACKGROUND: This study aimed to investigate the relationship between femoral neck fractures and sarcopenia. METHODS: This was a retrospective analysis of 92 patients with femoral neck fractures, from September 2017 to March 2020, who were classified into high ambulatory status (HG) and low ambulatory status (LG) groups. Ambulatory status was assessed before surgery, one week after surgery, at discharge, and during the final follow-up. To evaluate sarcopenia, muscle mass and fatty degeneration of the muscles were measured using preoperative CT. An axial slice of the superior end of the L5 vertebra was used to evaluate the paraspinal and psoas muscles, a slice of the superior end of the femoral head for the gluteus maximus muscle, and a slice of the inferior end of the sacroiliac joint for the gluteus medius muscle. The degeneration of the muscles was evaluated according to the Goutallier classification. RESULTS: The cross-sectional area of the gluteus medius and paraspinal muscles was significantly correlated with ambulatory status before the injury, at discharge, and during the final follow-up. CONCLUSIONS: Measurement of the gluteus medius and paraspinal muscles has the potential to evaluate sarcopenia and predict ambulatory status after femoral neck fractures.

The inferior gluteal artery anatomy: a detailed analysis with implications for plastic and reconstructive surgery.

BACKGROUND: The inferior gluteal artery (IGA) is a large terminal branch of the anterior division of the internal iliac artery (ADIIA). There is a significant lack of data regarding the variable anatomy of the IGA. MATERIALS AND METHODS: A retrospective study was conducted to establish anatomical variations, their prevalence and morphometrical data on IGA and its branches. The results of 75 consecutive patients who underwent pelvic computed tomography angiography were analysed. RESULTS: The origin variation of each IGA was deeply analysed. Four origin variations have been observed. The most common type O1 occurred in 86 of the studied cases (62.3%). The median IGA length was set to be 68.50 mm (lower quartile [LQ]: 54.29; higher quartile [HQ]: 86.06). The median distance from the origin of the ADIIA to the origin of the IGA was set to be 38.22 mm (LQ: 20.22; HQ: 55.97). The median origin diameter of the IGA was established at 4.69 mm (LQ: 4.13; HQ: 5.45). CONCLUSIONS: The present study thoroughly analysed the complete anatomy of the IGA and the branches of the ADIIA. A novel classification system for the origin of the IGA was created, where the most prevalent origin was from the ADIIA (type 1; 62.3%). Furthermore, the morphometric properties (such as the diameter and length) of the branches of the ADIIA were analysed. This data may be incredibly useful for physicians performing operations in the pelvis, such as interventional intraarterial procedures or various gynaecological surgeries.

Cosmetic Injection of Illicit Foreign Materials: Imaging Features and Patterns of Migration in 413 Cases.

BACKGROUND: The injection of illicit, nonregulated foreign materials is increasingly common and has negative consequences relative to the inflammatory process that ensues. OBJECTIVES: The aim of this study was to identify anatomical and imaging characteristics after the cosmetic injection of illicit foreign materials. METHODS: A retrospective review of clinical and imaging records was performed. The issues analyzed were the anatomical site, type of injected substance, imaging method for diagnosis, and patterns of migration. RESULTS: Data on 413 patients were collected. Most patients were female, with a mean age of 44 years. The most commonly infiltrated region was the buttocks (n = 284; 53.58%) followed by the breast (n = 99; 18.67%). Magnetic resonance imaging was the most common method of diagnosis in those patients who had an imaging study (159 out of 168). The most frequent depth of foreign material detected by imaging was the muscular plane (n = 103; 61.30%). Migration was detected in 56.55% of patients who had an imaging study. Most infiltrated substances were unknown; biopolymers were the most commonly identified substances. Depending on the type of substance, migration rates varied from 13% to 29%; rate differences were not statistically significant (P = .712). Migration was more common when the depth of infiltration was in muscle (77.66%) than in subcutaneous tissue (23.4%); this difference was statistically significant (P < .0001). CONCLUSIONS: Deep infiltration is related to greater migration rates, apparently regardless of the substance injected.

What Makes a Beautiful Buttock Beautiful? A Case-Control Study Comparing Buttocks Models versus Normal Women by Magnetic Resonance Imaging, Photography and Anthropometry.

OBJECTIVES: To describe characteristics of women with aesthetically ideal buttocks and differentiate them from women with normal buttocks. METHODS: Case-control study comparing anatomy of women with ideal buttocks (buttocks models) to women with normal buttocks using magnetic resonance images, anthropometric measurements and photography. RESULTS: Comparing to normal women, buttocks models have a narrower waist, narrower iliac crest, wider C point, wider hips and bigger and thicker gluteus maximus muscle (GMM). A bigger GMM adds more projection to the C point, point of maximum projection in the lateral view is 2.7 cm higher than the pubic bone. The amount of subcutaneous fat was equal in models and controls. CONCLUSIONS: Our study provides new knowledge regarding the tridimensional aspects of the beauty of the buttocks area. A beautiful buttock is a conjunction of adequate bony shape, muscle development, subcutaneous fat layer, and tight skin. Comparing to normal women, buttocks models have a narrower waist, narrower iliac crest, wider C point, wider hips and bigger and thicker Gluteus Maximus Muscle. Accurate understanding of the aesthetic goals in a given patient can guide surgical technique. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Aggressive gluteal fibromatosis: a rare case associated with spontaneous superior gluteal artery pseudoaneurysm.

Deep fibromatosis is a locally aggressive neoplasm commonly involving the extremities. Several authors have described imaging features and complications associated with deep fibromatosis. We present the case of a 33-year-old man who presented with a right gluteal fibrous mass identified on magnetic resonance imaging (MRI), which was associated with a pseudoaneurysm originating from the right superior gluteal artery on serial follow-up with MRI and computed tomography. No intervention was done, and after conservative management, spontaneous thrombosis of the pseudoaneurysm was developed. Such imaging finding is the first report of a spontaneous development of pseudoaneurysm caused by deep fibromatosis, which could be a life-threatening condition and should be considered when dealing with deep fibromatosis and deciding on the appropriate treatment.

Comparison of Lumbar Artery and Superior Gluteal Artery Perforator Flaps for Breast Reconstruction: Multislice CT-Based Anatomical Study.

BACKGROUND: Although the deep inferior epigastric artery perforator flap is the criterion standard for autologous breast reconstruction, lumbar artery perforator (LAP) and superior gluteal artery perforator (SGAP) flaps are recent trends as alternatives. The purpose of our study was to clarify differences of these flaps based on multislice CT findings of the same patient. METHODS: Retrospective study was conducted on 58 patients who underwent preoperative contrast-enhanced multislice CT for breast reconstruction using deep inferior epigastric artery perforator. Of these, 32 patients' data were evaluated excluding 26 patients' data either for the lumbar or gluteal fat being outside the imaging range or for nondepiction of the vascular pedicle origin of LAP or SGAP flap. Vascular pedicle diameter, pedicle length, and subcutaneous fat thickness were measured for LAP and SGAP flaps. RESULTS: The vascular pedicle diameter, pedicle length, and fat thickness were 2.1 (SD, 0.3) mm, 3.4 (SD, 0.4) cm, and 4.9 (SD, 1.0) cm, respectively, for LAP flaps; and 1.7 (SD, 0.2) mm, 5.6 (SD, 1.1) cm, and 2.7 (SD, 0.7) cm, respectively, for SGAP flaps. CONCLUSIONS: The LAP flaps had thicker subcutaneous fat and a larger vascular pedicle diameter, whereas the SGAP flaps had a longer vascular pedicle. As donor material for breast reconstruction, the LAP flap is indicated for cases where absolute volume is needed; otherwise, the SGAP flap is more advantageous as it facilitates vascular anastomosis with its longer vascular pedicle.

Embolization of Large Internal Iliac Artery Pseudoaneurysm through a Retrograde Trans-Superior Gluteal Arterial Access.

The presence of osteal stenosis/occlusion or osteal exclusion by prior interventions poses a challenge to selective catheterization of the internal iliac artery. We describe a case where a retrograde access through the superior gluteal artery (SGA) was used to successfully treat an internal iliac artery pseudoaneurysm (PSA) in a patient when an antegrade catheterization was not feasible due to internal iliac osteal exclusion by an endograft.

MRI assessment of minimally invasive anterolateral approaches in total hip arthroplasty.

INTRODUCTION: Total hip arthroplasty (THA) on a minimally invasive anterolateral (MIAL) approach frequently leads to gluteus minimus and gluteus medius lesions, and sometimes to tensor fasciae latae (TFL) denervation. We therefore developed compensatory strategies, which we assessed on pre- and post-operative MRI: 1) to assess gluteus minimus and gluteus medius fatty infiltration (FI), 2) to assess TFL FI, and 3) to assess FI in the other periarticular muscles. HYPOTHESIS: The modified MIAL approach reduces the rate of gluteus minimus and gluteus medius lesion. MATERIALS AND METHODS: A continuous prospective single-surgeon series of THA using a MIAL approach included 25 patients. Femoral implantation was performed with the hip in extension so as to distance the proximal femur from the gluteals, avoiding muscle trauma. The superior gluteal nerve branch in the space between the gluteus medius and TFL, running toward the TFL, was systematically released and protected. MRI was performed preoperatively and at 3 months and 1 year post-surgery. FI was analyzed according to the Goutallier classification in all periarticular muscles. RESULTS: One patient lacked preoperative MRI and was excluded, leaving 24 patients, for 72 MRIs. In 10/24 patients (41.7%) the gluteus minimus and in 8/24 patients (33.3%) the anterior third of the gluteus medius showed ≥2 grade increase in FI between preoperative and 1-year MRI, with significant increases in both at 3 months (p<0.001) and 1 year (p<0.001). At least a 2 grade increase in FI at 1 year was seen in 1 patient (4.2%) in the TFL, in 2 (8.3%) in the piriformis, and in 1 (4.2%) in the obturator internus. There were no significant differences in FI between preoperative, 3-month or 1-year MRI in any other periarticular muscles. CONCLUSION: Femoral implantation in hip extension did not reduce the rate of gluteal lesions, which remained frequent. In contrast, release of the superior gluteal nerve branch could be effective in conserving TFL innervation. Some rare lesions of the proximal part of the pelvi-trochanteric muscles were also observed. LEVEL OF EVIDENCE: IV, Prospective case series.

Comparative MRI assessment of three minimally invasive approaches in total hip arthroplasty.

INTRODUCTION: Minimally invasive approaches (direct anterior approach: DAA; minimally invasive anterolateral: MIAL; piriformis-sparing posterior approach: PSPA) are widely used for total hip arthroplasty (THA), with a muscle-sparing objective. There are no published comparative studies of muscle damage secondary to these approaches. The aim of the present study was to compare fatty infiltration (FI) on MRI induced by DAA, MIAL and PSPA in THA 1) in the tensor fasciae latae (TFL) and sartorius muscles, 2) in the gluteal muscles, and 3) in the pelvitrochanteric muscles. HYPOTHESIS: Greater FI is induced by DAA in anterior muscles, by MIAL in gluteal muscles and by PSPA in pelvitrochanteric muscles. MATERIALS AND METHODS: Three continuous prospective series of THA by DAA, MIAL and PSPA included 25 patients each. MRI was performed preoperatively and at 1 year postoperatively. FI was graded on the Goutallier classification in all periarticular hip muscles. Muscles showing ≥2 grade aggravation at 1 year were considered damaged. RESULTS: Nine patients whose preoperative MRI was uninterpretable were excluded. In all, 66 patients (21 DAA, 24 MIAL and 21 PSPA) with 132 MRI scans were analyzed. TFL was damaged in 2/21 DAA patients (9.5%), 1/24 MIAL patients (4.2%) and 0/21 PSPA patients (0%). There were no sartorius lesions. The anterior third of the gluteus medius was damaged in 8/24 MIAL patients (33.3%) and the gluteus minimus in 10/24 (41.7%), compared to 1/21 DAA patients (4.8%) and 0/21 PSPA patients (0%). The mid and posterior thirds of the gluteus medius and the gluteus maximus were never damaged. The piriformis muscle was damaged in 3/21 DAA patients (14.3%), 2/24 MIAL patients (8.3%) and 2/21 PSPA patients (9.5%). The obturator internus was damaged in 4/21 DAA patients (19%), 1/24 MIAL patients (4.2%) and 16/21 PSPA patients (76.2%). The obturator externus and quadratus femoris were mainly damaged in PSPA patients: respectively, 5/21 (23.8%) and 4/21 patients (19%)). CONCLUSION: The muscle-sparing properties of minimally invasive hip approaches are only theoretical. In the present series, there were rare TFL lesions with DAA and MIAL. Gluteus medius and minimus lesions were frequent in MIAL. Pelvitrochanteric muscles lesions were more frequent in PSPA, but found in all 3 approaches. These findings should help guide surgeons in their choice of approach and in informing patients about the damage these minimally invasive approaches can cause. LEVEL OF EVIDENCE: III, prospective comparative study.

Prevalence of Contralateral Hip Abductor Tears and Factors Associated With Symptomatic Progression.

BACKGROUND: Patients with gluteus medius tendinopathy present with laterally based hip pain that can be diagnosed under the greater trochanteric pain syndrome diagnosis. Magnetic resonance imaging (MRI) can assist in diagnosing pathology of the symptomatic hip, and when a pelvic MRI that includes both hips, the clinician may identify asymptomatic tears in the nonsurgical hip. In patients who undergo unilateral gluteus medius repairs, little is known about the prevalence or subsequent onset of clinical symptoms in the nonsurgical hip. PURPOSE: To describe (1) the prevalence of asymptomatic contralateral gluteus medius tears in patients with unilateral symptoms, (2) the presentation and time before symptom onset, and (3) the morphological characteristics on MRI of future symptomatic tears. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 51 consecutive patients who underwent gluteus medius tear surgery were reviewed for contralateral hip pathology; of these, 43 patients were 2 years out from index surgery with reviewable preoperative MRI scans. A musculoskeletal radiologist reviewed the MRI scans for tear size, tendon retraction, and fatty infiltration using the Goutallier-Fuchs grading system. Medical record review identified contralateral hips requiring subsequent treatment. RESULTS: Of the original 43 patients, 10 (23%) had no contralateral tear, 19 (44%) had low-grade partial tears, 9 (20%) had high-grade partial tears, and 5 (11%) had full-thickness tears. Thirty-seven patients had unilateral symptoms; the other 6 had mild contralateral hip pain at enrollment. Of the 37 patients with unilateral symptoms, 27 (73%) had a contralateral tear; of those, 10 became symptomatic at an average of 24 months after index presentation (range, 6-50 months). In patients with symptomatic progression, 7 had low-grade partial tears, 1 had a high-grade partial tear, and 2 had full-thickness tears, with an average retraction of 17 mm. Tendon tear grade on MRI did not always correlate with symptoms or future presentation. All symptomatic progression remained mild to moderate. Seven patients required a corticosteroid injection, and none needed contralateral hip surgery within 2 years. CONCLUSION: Of patients who underwent surgery for a gluteus medius tear, 73% (27/37) had an incidental MRI-confirmed contralateral hip abductor tear. Of these, 37% (10/27) developed symptoms consistent with greater trochanteric pain syndrome during the 2-year study period.

Distant migration of gluteal augmentation fat presenting as a soft tissue knee mass.

Gluteal augmentation with autologous fat grafting is an increasingly popular procedure. While complication rates are low, the clinical and imaging evaluation of the various complications can be challenging. We report a case of distal migration of a failed gluteal fat graft in a young female patient presenting as a soft tissue mass in the knee, mimicking a soft tissue sarcoma. Surgical resection of the migrated fat graft confirmed the diagnosis. The diagnosis was challenging as the patient was initially reluctant to disclose her surgical history due to perceived negative social stigmas related to cosmetic contouring procedures. This case highlights the imaging findings of a rare complication following autologous fat grafting for gluteal augmentation and the importance of obtaining a thorough medical history.

The relationship between gluteus medius and minimus muscle volumes and hip development in developmental dysplasia of the hip.

BACKGROUND: Several studies in adult hips have revealed the role of the gluteus medius (Gmed) and gluteus minimus (Gmin) muscles in maintaining the stability and centripetal force of the hip joint. Hip centripetality in developmental dysplasia of the hip (DDH) patients contributes to subsequent healthy hip development later in life. The purpose of this study is to investigate the relationship between Gmed and Gmin volume and centripetality of the hip in infant DDH patients. METHODS: We retrospectively enrolled 41 unilateral DDH patients (4 males, 37 females) who were treated by closed reduction from 2006 to 2016 and underwent magnetic resonance imaging at around 2 years old. Gmed, and Gmin volume was measured in magnetic resonance imaging. We defined both Gmin and Gmed together as hip abductor gluteus muscles (GMs; Gmed + Gmin). The muscle volume ratio of the affected side was calculated by dividing the GMs volume of the affected side by the contralateral side. Relationships between center-head distance discrepancy (CHDD) at 2 years old, and at 4-6 years old and GMs volume ratio were investigated by Pearson's correlation coefficient within the same patients. RESULTS: Mean age of closed reduction was 0.8 years old and mean age at MRI was 2.2 years old with a mean follow-up period of 3.7 years. Mean GMs volume in the affected side, contralateral side, and muscle volume ratio were 25.3 cm3, 27.0 cm3, and 0.94, respectively. GMs volumes were significantly higher in the contralateral side (p < 0.001). GMs volume ratio at 2 years old significantly correlated with CHDD at 4-6 years old (p < 0.05). CONCLUSION: GMs volume at 2 years old was found to be associated with later hip afferents. Promoting the healthy development of GMs by properly maintaining the infant's natural hip movement is important for the healthy hip development. LEVEL OF EVIDENCE: Level III.

Cytological features of BCOR-CCNB3 sarcoma: Comparison with Ewing sarcoma and synovial sarcoma.

INTRODUCTION: BCOR-CCNB3 sarcoma (BCS) is one of the histological types classified as an undifferentiated small round cell sarcoma of bone and soft tissue. This sarcoma frequently develops in males under 20 years of age. Histologically, a delicate capillary network has been reported as a conspicuous finding. In this study, the cytological findings of BCS were observed in two cases of primary lesions and one case of a lung metastatic lesion. The cytological findings of BCS were compared with its histological mimics, and the characteristic findings of BCS were examined. METHODS: Three cases of BCS were studied, and a cytological comparison was performed with 8 cases of Ewing sarcoma (ES) and 10 cases of synovial sarcoma (SS; monophasic type: 7 cases, biphasic type: 2 cases, poorly differentiated: 1 case). RESULTS: In all BCS cases, small clusters with thin and delicate vascular cores and tiny vascular fragments were conspicuous. In ES and SS cases, although small clusters with vascular cores were observed, the vascular cores were thicker than in BCS, and no tiny vascular fragments appeared in most cases. Cytomorphological differences of tumour cells were also observed among BCS, ES, and SS. Predominantly rounded nuclei with fine chromatin and inconspicuous nucleoli can be cytological clues for BCS. CONCLUSIONS: BCS shows characteristic cytological findings that make the diagnosis of BCS more likely than that of ES and SS. Cytological evaluation is a useful tool for appropriate differential diagnosis that leads to a more accurate final diagnosis and rapid treatment.