Imaging of peripheral nerve causes of chronic buttock pain and sciatica.

Chronic buttock pain is a common and debilitating symptom, which severely impacts daily activities, sleep, and may affect athletic performance. Lumbar spine, posterior hip, or hamstring pathology are usually considered as the primary diagnoses; however, pelvic neural pathology may be a significant cause of chronic buttock pain, particularly if there are prolonged (>6 months) buttock and/or radicular symptoms. The subgluteal space is the site of most pelvic causes of neural-mediated buttock pain, primarily relating to entrapment neuropathy of the sciatic nerve (deep gluteal syndrome), although other nerves within the subgluteal space including the gluteal nerves, pudendal nerve, and posterior cutaneous nerve of thigh may also be involved. Additionally, cluneal nerve entrapment at the iliac crest may result in "pseudo-sciatica". Anatomical variants of the pelvic girdle muscles and functional factors, including muscle spasm and pelvic instability, may contribute to development of deep gluteal syndrome, along with neural senescence. Imaging findings primarily relate to the presence of sciatic neuritis and peri-sciatic pathology, including neural compression and peri-neural adhesions or fibrosis. This imaging review describes the causes, magnetic resonance imaging and ultrasound imaging findings and imaging-guided treatment of pelvic neural causes of chronic buttock pain and sciatica.

Angiosomal Vascular Occlusions, Deep-Tissue Pressure Injuries, and Competing Theories: A Case Report.

ABSTRACT: Compression of the soft tissue between a support surface and a bony prominence has long been the accepted primary mechanism of pressure injury (PrI) formation, with the belief that said compression leads to capillary occlusion, ischemia, and tissue necrosis. This explanation presupposes an "outside-in" pathophysiologic process of tissue damage originating at the local capillary level. Despite advances in prevention protocols, there remains a stubbornly consistent incidence of severe PrIs including deep-tissue injuries, the latter usually evolving into stage 4 PrIs with exposed bone or tendon. This article presents just such a perioperative case with the aim of providing further evidence that these more severe PrIs may result from ischemic insults of a named vessel within specific vascular territories (labeled as angiosomes). Pressure is indeed a factor in the formation of severe PrIs, but these authors postulate that the occlusion occurred at the level of a named artery proximal to the lesion. This vascular event was likely attributable to low mean arterial pressure. The authors suggest that the terminology proposed three decades ago to call both deep-tissue injuries and stage 4 PrIs "vascular occlusion pressure injuries" should be the topic of further research and expert consensus.

Appropriate sites for the measurement of the cross-sectional area of the gluteus maximus and the gluteus medius muscles in patients with hip osteoarthritis.

PURPOSE: To evaluate the relationship between the volume, cross-sectional area, and peak isometric muscle strength of the gluteus maximus and gluteus medius muscles in patients with hip osteoarthritis, and to use this information to identify effective sites for measurement of the cross-sectional area of these muscles. METHODS: Twenty-four patients with hip osteoarthritis were included. The muscle cross-sectional area and volume were calculated from magnetic resonance images. The cross-sectional area was calculated at three levels: the inferior point of the sacroiliac joint, just above the femoral head, and at the greatest muscle diameter. Peak isometric strength was assessed using hand-held dynamometry, using the extension and external rotation for the gluteus maximus and abduction and internal rotation for the gluteus medius. Measured outcomes were compared between the two muscles, and the association between muscle volume, cross-sectional area, and peak isometric muscle strength was evaluated using Pearson's correlation. RESULTS: Volume was correlated with the cross-sectional area in the gluteus maximus (r ≥ 0.707) and with the cross-sectional area (r ≥ 0.637) and peak isometric strength (r ≥ 0.477) in the gluteus medius. There was no difference between the cross-sectional area measured at the greatest muscle diameter and just above the femoral head (p = 0.503) for the gluteus maximus and at the inferior point of the sacroiliac joint (p = 0.651) for the gluteus medius. CONCLUSION: The cross-sectional area, when used to calculate the muscle volume, should be evaluated just above the femoral head for the gluteus maximus and at the inferior point of the sacroiliac joint for the gluteus medius.

Pain Syndromes Secondary to Cluneal Nerve Entrapment.

PURPOSE OF REVIEW: The purpose of this review is to provide an overview of the cluneal nerves, present a summary of pain syndromes secondary to clunealgia, and evaluate current literature for diagnostic and treatment modalities. RECENT FINDINGS: Multiple trials and studies have reported success with numerous modalities ranging from nerve blocks, neuroablation, and even peripheral neuromodulation with varying degrees of clinical benefit. Cluneal nerve entrapment or chronic impingement can cause buttock pain or referred pain to nearby areas including the lower back, pelvic area, or even the lower extremities. Clunealgias and associated pain syndromes can often be challenging to diagnose and differentiate. An appreciation of the pathophysiology of clunealgias can assist with patient selection for interventional pain strategies targeted towards the cluneal nerves, including nerve blocks, neuroablation, and peripheral neuromodulation. More research is needed to better delineate the efficacy of these procedures for clunealgias.

Could the tendon degeneration and the fatty infiltration of the gluteus medius affect clinical outcome in total hip arthroplasty?

PURPOSE: The aim of this prospective study was to perform a clinical and radiologic evaluation of patients undergoing total hip arthroplasty (THA). The hypothesis is that there is a correlation between the pre-operative degeneration state of the gluteal muscle-tendinous unit and the clinical outcome in terms of functional recovery. METHODS: Fifty-five patients have met inclusion criteria. All patients included in the sample were subjected to clinical evaluation. The ultrasound examination of the patients of the study was conducted and the following parameters were assessed: Thickness in mm of the gluteus medius tendon; Quality of the gluteus medius tendon; and Trophy and muscular composition. RESULTS: The degree of degeneration of the pre-operative tendon shows a negative statistical correlation with all the pre- and post-operative clinical scales, but presents statistical significance (p < 0.05) only with the post-operative Harris, the post-operative Oxford, the Harris and HOOS-modified post-operative, lameness, and Trendelenburg; it correlates positively with the quality of the macroscopic tendon detected intra-operatively, the degree of the pre-operative contralateral tendon, and the operated and contralateral pre-operative muscle (p < 0.05). The degree of fatty degeneration of the pre-operatively operated muscle correlates negatively (p < 0.05) with all pre- and post-operative clinical scales except for the pre-operative WOMAC and HOOS modified, with the lameness and the Trendelenburg sign; it correlates positively (p < 0.05) with age, the quality of the macroscopic tendon detected intra-operatively, degree of tendon degeneration, fatty infiltration of the contralateral pre- and post-operative muscle and of the post-operative operated muscle. CONCLUSION: Tendon degeneration and fatty infiltration of the gluteus medius muscle appeared to be determinants of the post-operative persistence of lameness and Trendelenburg sign positivity in patients undergoing hip arthroplasty.

Seated buttocks anatomy and its impact on biomechanical risk.

AIM: The objective of this study was to describe the amount, types, and shapes of tissue present in the buttocks during sitting (i.e., seated buttocks soft tissue anatomy), and the impact of seated buttocks soft tissue anatomy on biomechanical risk. MATERIALS AND METHODS: The buttocks of 35 people, including 29 full-time wheelchair users with and without a history of pelvic pressure ulcers were scanned sitting upright on 3" of flat HR45 foam in a FONAR Upright MRI. Multi-planar scans were analyzed to calculate bulk tissue thickness, tissue composition, gluteus maximus coverage at the ischium, the contour of the skin, and pelvic tilt. RESULTS: Bulk tissue thickness varied from 5.6 to 32.1 mm, was composed mostly of adipose tissue, and was greatest in the able-bodied cohort. Skin contours varied significantly across status group, with wheelchair users with a history of pressure ulcers having tissue with a peaked contour with a radius of curvature of 65.9 mm that wrapped more closely to the ischium (thickness at the apex = 8.2 mm) as compared to wheelchair users with no pressure ulcer history (radius of curvature = 91.5 mm and apex thickness = 14.5 mm). Finally, the majority of participants presented with little to no gluteus coverage over their ischial tuberosity, regardless of status group. CONCLUSIONS: This study provides quantitative evidence that Biomechanical Risk, or the intrinsic characteristic of an individual's soft tissues to deform in response to extrinsic applied forces, is greater in individuals at greater risk for pressure ulcers.

Gluteal Burns from a Car Seat Heater in a Neurologically Intact Patient: A Case Report.

BACKGROUND: Car seat heaters are an increasingly common amenity in vehicles in the United States, but they have been shown to place neurologically impaired patients at risk for significant burns. CASE REPORT: We discuss the case of a neurologically intact and otherwise healthy 49-year-old man who presented to the Emergency Department with second-degree gluteal and posterior upper thigh burns after using a car seat warmer for 8 consecutive hours. At no point during the course of his drive did he experience discomfort beyond feeling slightly warm. The patient was treated with supportive therapy and standard wound care, and he had a full recovery after 10 days. We review the pathophysiology of burns and discuss how seat heaters can place even neurologically intact patients at risk for significant burn injuries. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case is the first published report of a neurologically intact patient sustaining significant burns from the use of a car seat heater. This case illustrates that burn injuries can develop after prolonged exposure even at low temperatures. Emergency physicians should perform a careful skin examination on all patients presenting with gluteal discomfort in whom a history of car seat warmer use is obtained.

Hip Abductor and Adductor Muscles Activity Patterns During Landing After Anterior Cruciate Ligament Injury.

CONTEXT: Hamstring and quadriceps activity adaptations are well known in individuals with anterior cruciate ligament deficiency (ACLD) and reconstructed (ACLR) to potentially compensate for knee joint instability. However, few studies have explored hip muscles activity patterns after ACL injury. OBJECTIVE: To examine the activation characteristics of gluteus medius (GMED) and adductor longus in ACLR and ACLD subjects compared with controls. DESIGN: Case-control study. SETTING: Athletic training room and university lab. PARTICIPANTS: Twelve healthy and 24 ACL-injured (12 ACLR and 12 ACLD) recreationally active male volunteers. INTERVENTIONS: Surface electromyography of the GMED and adductor longus were recorded during a single-leg vertical drop landing and normalized to maximum voluntary isometric contractions. MAIN OUTCOME MEASURES: Preparatory and reactive muscle activity and coactivation were analyzed from 100 milliseconds prior to initial contact to 250 milliseconds postcontact. RESULTS: During reactive activity, ACL-injured (ACLR and ACLD) participants demonstrated significantly lower peak GMED activity compared with controls (F = 4.33, P = .02). In addition, ACLR participants exhibited significantly lower reactive GMED:adductor longus coactivation muscle activity compared with controls (F = 4.09, P = .03). CONCLUSION: Our findings suggest neuromuscular adaptations of the hip musculature are present in people at least 2 years from ACL injury. GMED activation exercises should be considered in designing rehabilitation programs for ACL-injured individuals.

Detection of Gluteal Changes Using Ultrasound Imaging During Phases of Gait in Individuals With Medial Knee Displacement.

Context: Medial knee displacement (MKD) is a common risk factor for lower-extremity injury and is related to altered gluteal muscle activity. Ultrasound imaging (USI) is a reliable means to explore mechanical muscle activity; however, no information exists regarding USI of the gluteals during gait in an MKD population. Objective: To determine differences in USI gluteal muscle activity during gait in individuals with and without MKD. Design: Descriptive laboratory study. Setting: University research laboratory. Participants: Out of 28 participants, 14 exhibiting MKD unilaterally during a single-leg squat (19.36 [1.51] y, 169.73 [7.50] cm, and 62.01 [10.57] kg; 10 females) and 14 matched non-MKD subjects (20.29 [1.73] y, 167.24 [9.07] cm, and 67.53 [16.03] kg). Interventions: Bilateral B-mode USI of the gluteus maximus (Gmax) and gluteus medius (Gmed) muscles during quiet stance, heel strike, and a 10-second treadmill walking clip. Main Outcome Measures: Gluteal thickness measures normalized to quiet stance yielded activity ratios, and percentage of muscle thickness change was assessed between heel strike and quiet stance. Differences between groups were assessed with Cohen's d effect sizes with 95% confidence intervals. Activity ratios with 90% confidence intervals plotted on 10% intervals from 0% to 100% of gait were used to compare groups and limbs. A subsample of images was measured to determine intertester reliability. Results: USI revealed decreased Gmax and Gmed percent change at heel strike (%change = -9.57% [7.15%] and -8.76% [4.26%], respectively). The MKD limb compared with the contralateral limb exhibited decreased Gmed activity ratio at 30% of gait (MKD = 0.89 [0.056]; non-MKD = 1.01 [.052]). Intertester reliability was excellent for gluteus maximus (intraclass correlation coefficient = .987 [.014]) and Gmed (intraclass correlation coefficient = .989 [.013]) measurements. Conclusions: USI highlighted gluteal activity differences of MKD limbs during gait, which may contribute to inadequate hip stabilization during this daily repetitive task. These findings potentiate the use of USI as an intervention- or screening-based visual tool.

Hip abductor muscle activity during walking in individuals with gluteal tendinopathy.

The external hip adduction moment during walking is greater in individuals with gluteal tendinopathy (GT) than pain-free controls. Although this likely represents a greater demand on the hip abductor muscles implicated in GT, no study has investigated activation of these muscles in GT. For this purpose, fine wire electrodes were inserted into the segments of the gluteus minimus and medius muscles, and surface electrodes placed on the tensor fascia lata, upper gluteus maximus, and vastus lateralis muscles of eight individuals with, and eight without, GT. Participants underwent six walking trials. Individual muscle patterns were compared between groups using a wavelet-based linear effects model and muscle synergy analysis performed using non-negative matrix factorization to evaluate muscle activation patterns, within- and between-participant variability. Compared to controls, individuals with GT exhibited a more sustained initial burst of the posterior gluteus minimus and middle gluteus medius muscle segments. Two muscle synergies were identified; Synergy-1 activated in early-mid stance and Synergy-2 in early stance. In GT participants, posterior gluteus minimus and posterior gluteus medius and tensor fascia lata contributed more to Synergy-1 active during the period of single leg support. Participants with GT exhibited reduced within-participant variability of posterior gluteus medius and reduced between-participant variability of anterior gluteus minimus and medius and upper gluteus maximus. In conclusion, individuals with GT exhibit modified muscle activation patterns of the hip abductor muscles during walking, with potential relevance for gluteal tendon loading.

Measuring the impact of cushion design on buttocks tissue deformation: An MRI approach.

AIM: To establish a research approach for describing how different wheelchair cushion designs impact buttocks tissue deformation during sitting. MATERIALS AND METHODS: The buttocks of 4 individuals with spinal cord injury and significant atrophy were scanned sitting in a FONAR Upright MRI. Scans were collected with the individuals' buttocks fully suspended without pelvic support, and seated on 3 different commercially available wheelchair cushions. Multi-planar scans were analyzed to provide 3D renderings and measurements of tissue thickness and shape. RESULTS: Bulk tissue thicknesses at the ischium, which rarely included muscle, were reduced by more than 60% on enveloping cushion designs studied (i.e., Roho HP and Matrx Vi), and more variably (23-60%) on an orthotic off-loading design (i.e., Java). Adipose was typically displaced posterior and superior from the unloaded condition, with more lateral displacement on the Roho HP and Matrx Vi and more medial displacement present on the Java. Large changes in angle at the sacro-coccygeal joint indicated significant loading on the region. Deformation at the greater trochanter was more consistent across surfaces. Greater interface pressures tended to be associated with greater deformation, but the relationship varied by individuals and was highly non-linear. CONCLUSIONS: The buttocks in this study all deformed significantly, but at different locations and in different manners across all 3 surfaces. Attention needs to be paid to the regions of greatest deformation. A future metric of shape compliance should consider cushion performance at all high risk regions, and changes to the amount and shape of tissue in the regions of interest.

Deep tissue loads in the seated buttocks on an off-loading wheelchair cushion versus air-cell-based and foam cushions: finite element studies.

For wheelchair users, a common injury is a sitting-acquired pressure ulcer (PU) which typically onsets near the interface between the ischial tuberosity (IT) and the overlying soft tissues. The risk of developing PUs can be reduced considerably if an adequate cushion is placed on the wheelchair in order to protect tissues from PUs by minimising interface mechanical loads between the body and cushion and also, exposure to internal soft tissue loads. In this work, we studied the biomechanical performances of an off-loading (OL) cushion with limited adjustability, in comparison to a standard foam cushion and a fully adjustable air-cell-based (ACB) cushion. These different cushion design approaches were methodologically and quantitatively analysed and compared here using a finite element (FE) modelling framework. We determined the internal mechanical deformations, strains and stresses in soft tissues of the seated buttocks during symmetric sitting, in a specific anatomy of a person with a spinal cord injury that was acquired during sitting in an open, magnetic resonance imaging configuration. Our results have shown that strains and stresses in muscle, fat and skin tissues are orders of magnitude lower for the ACB cushion with respect to the standard foam and OL cushions. The OL cushion design has taken the approach of protecting at-risk sites of the buttocks by transferring local internal tissue loads away from the ITs and towards the greater trochanters, at the price of increasing exposure to internal tissue loads at sites other than the ITs. The ACB cushion design, however, has taken a different approach, that is, immersion and envelopment of the entire buttocks structure, which is useful for minimising the exposure to internal tissue loads throughout the whole buttocks. Quantifying performances of wheelchair cushions using FE modelling provides insights into deep tissue loads, which is essential for informed decision-making in developing sitting solutions for individuals at risk, as well as for patient groups.

A case series and a review of the literature on foreign modelling agent reaction: an emerging problem.

Foreign modelling agent reactions (FMAR) are the result of the injection of unapproved high-viscosity fluids with the purpose of cosmetic body modelling. Its consequences lead to ulceration, disfigurement and even death, and it has reached epidemic proportions in several regions of the world. We describe a series of patients treated for FMARs in a specialised wound care centre and a thorough review of the literature. A retrospective chart review was performed from January 1999 to September 2015 of patients who had been injected with non-medical foreign agents and who developed cutaneous ulceration needing treatment at the dermatology wound care centre. This study involved 23 patients whose ages ranged from 22 to 67 years with higher proportion of women and homosexual men. The most commonly injected sites were the buttocks (38·5%), legs (18%), thighs (15·4%) and breasts (11·8%). Mineral oil (39%) and other unknown substances (30·4%) were the most commonly injected. The latency period ranged from 1 week to 17 years. Complications included several skin changes such as sclerosis and ulceration as well as systemic complications. FMAR is a severe syndrome that may lead to deadly complications, and is still very common in Latin America.

Squamous cell carcinoma complicating a chronic lesion of hidradenitis suppurativa: a case report and review of the literature.

Squamous cell carcinoma (SCC) arising from chronic hidradenitis suppurativa (HS) is rare; however, the morbidity associated with this presentation is high and management has not been standardised or optimised. We present a case of HS of the perineum and buttocks complicated by SCC, requiring multiple extensive surgical resections. Adjuvant radiotherapy was withheld initially because of concern for poor healing of the surgical wound but was eventually initiated after a second recurrence was identified. The patient ultimately expired 4 years after the initial diagnosis of SCC. We also review 80 cases of SCC complicating HS found in the English literature. Case reports and mechanistic studies suggest the possibility that human papilloma virus and smoking may be risk factors associated with SCC in HS. Despite the majority of SCC cases being well-differentiated tumours in HS, the highly aggressive nature of SCC in HS and its high likelihood for rapid progression, recurrence, metastasis and high mortality suggests the need to advocate for aggressive treatment. We recommend an aggressive approach to management at the time of SCC diagnosis in HS, which includes appropriate imaging to establish the extent of the tumour, large and deep surgical excision, sentinel lymph node evaluation, consultation with radiation oncology for potential adjuvant radiation therapy and close surveillance.

Pediatric Positional Sitting Dermatitis: A New Form of Pediatric Contact Dermatitis.

We report on four pediatric patients who presented with localized dermatitis in areas subject to repetitive friction due to their sitting positions. We propose that the cause of the eruption was irritant contact dermatitis due to frequently sitting in a crossed-leg sitting position, an entity for which we have coined the term pediatric positional sitting dermatitis (PPSD). The goal of this report is to raise clinicians' awareness of PPSD, which to our knowledge has not been previously described, and to discuss management of these patients.

Intensive vasodilatation in the sciatic pain area after dry needling.

BACKGROUND: Short-term vasodilatation in the pain area after dry needling (DN) of active trigger points (TrPs) was recorded in several cases of sciatica. Moreover, the presence of TrPs in sciatica patients secondary to primary lesion was suggested. Still, it is not known how often they occur and if every TrPs can provoke vasomotor reactions. The purpose of this study was to evaluate the prevalence of active TrPs among subacute sciatica patients and the response to DN under infrared thermovision (IRT) camera control. METHOD: Fifty consecutive Caucasian patients (mean age 41.2 ± 9.1y) with subacute sciatica were diagnosed towards gluteus minimus TrPs co-existence. Based on TrPs confirmation, patients were divided into two groups: TrPs-positive and TrPs-negative, than DN under IRT control was performed. Skin temperature changes and the percentage size of vasomotor reactions in the pain area were evaluated if present. RESULTS: The prevalence of active TrPs was 32.0%. Every TrPs-positive presented vasodilatation dependent on TrPs co-diagnosis (r = 0.72 p < 0.000) and pain recognition during DN (r = 0.4 p < 0.05). The size of vasodilatation in TrPs-positive subjects was: post-DN 12.3 ± 4.0% and post-observation 22.1 ± 6.1% (both p = 0.000) versus TrPs-negative: post-DN 0.4 ± 0.3% and post-observation 0.4 ± 0.2%. A significant temperature increase in the thigh and calf was confirmed for TrPs-positive subjects only (both p < 0.05). Post-DN and post-observation temperatures were as follows: average (thigh:1.2 ± 0.2°C; 1.4 ± 0.2°C, both p < 0.05 and calf: 0.4 ± 0.2°C; 0.4 ± 0.3°C, both p < 0.05) and maximum (thigh 1.4 ± 0.3°C 1.6 ± 0.3°C; both p < 0.05). CONCLUSIONS: The presence of active TrPs within the gluteus minimus muscle among subacute sciatica subjects was confirmed. Every TrPs-positive sciatica patient presented DN related vasodilatation in the area of referred pain. The presence of vasodilatation suggests the involvement of sympathetic nerve activity in myofascial pain pathomechanism. Although the clinical meaning of TrPs in subacute sciatica patients is possible, further studies on a bigger group of patients are still required. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12614001060639. Registered 3 October 2014.

Bilateral gluteal ischemic necrosis mistaken for stage IV pressure wound: case report and discussion.

BACKGROUND: Sacral and gluteal pressure wounds are a common problem in elderly and critically ill patients. Prompt and accurate diagnosis is important to determine the best plan of treatment. CASE: A 48-year-old female was hospitalized with severe trunk pain and bilateral necrotic gluteal wounds present for more than 1 year initially diagnosed as stage IV pressure ulcers; she reported pain radiating to her lower extremities. She had multiple comorbid conditions, including peripheral vascular disease, smoking, and hypertension. CONCLUSION: Wound care providers should be aware of this differential diagnosis especially in patients with history of vascular disease.

[Prognosis of embolization of internal iliac artery during the endovascular repair for abdominal aortic aneurysm].

OBJECTIVE: To study the importance of the internal iliac artery (IIA) during the endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA). METHODS: Forty-six consecutive cases of AAA treated by EVAR were retrospectively analyzed. The complications after exclusion of the IIA were analyzed. RESULTS: The bilateral IIAs were reserved in 18 cases, in which the follow-up was achieved in 16 cases and no complication was observed. The IIAs were excluded in 28 (60.9%) cases, in which the bilateral, right and left IIAs were excluded in 7 (15.2%), 14 (30.4%) and 7 (15.2%) cases respectively. The follow-up was achieved in 26 cases. Buttock claudication was observed in 12 (46.2%) cases, altered bowel habit was observed in 8 (32.0%) cases, erectile dysfunction was observed in 3 (12.0%) cases, and bloody stool was observed in 2 (8.0%) cases. Comparing the bilateral and unilateral IIA exclusions, the rates of buttock claudication were 50.0% vs. 45.0%, altered bowel habit 33.3% vs. 31.6%, and erectile dysfunction 33.3% vs. 5.3% respectively. And the average duration of buttock claudication of bilateral IIAs exclusion (8.3 months) was longer than that of unilateral exclusion (4.7 months). Moreover, comparing the left and right IIA exclusions, the rates of buttock claudication were 57.1% vs. 38.5%, altered bowel habit 57.1% vs. 16.7%, and bloody stool 28.6% vs. 0 respectively. And the average duration of buttock claudication of left IIA exclusion (6.0 months) was longer than that of right exclusion (3.7 months). CONCLUSION: The IIAs, especially the left IIA, should be reserved during the EVAR for AAA.

Age-related ptosis of the buttock: an anthropometric gender-specific analysis.

UNLABELLED: Buttock reshaping has received a lot of attention, although to date there are no anthropometric gender-specific datasets to show the aging of the gluteal region from infancy to old age to guide surgical planning of gender-specific buttock reshaping. To make surgical planning easier, we analyzed the characteristics of the aging buttock in 280 volunteers ranging in age from 15 to 85 years and classified the age characteristics of the gluteal region into gender-specific categories to establish a classification system that could guide surgical techniques needed to reshape and rejuvenate the buttock. Based on our measurements it was evident that males showed fewer signs of atrophy and less ptosis of their buttock with less reduction of the gluteal volume as they aged than did females. Based on the results, it is concluded that gender-specific surgical rejuvenation of the buttock area should include shortening of the gluteal crease, lifting the gluteal mass, adding volume, and smoothening of curvature to the lateral sides of the gluteal region. LEVEL OF EVIDENCE IV: 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 .