Combined application of gluteus maximus muscle flaps and random pattern skin flaps in repairing sacrococcygeal sinus tracts: a prospective study and technical note.

BACKGROUND: Sacrococcygeal sinus ulcers are caused by pressure sores, trauma, or surgery. Several surgical techniques have been developed for its treatment; however, studies are ongoing to develop the ideal method. The present study aims to introduce an innovative application of gluteus maximus muscle flaps (GMMFs) packing combined with local random pattern skin flaps (RPSFs) in repairing sacrococcygeal sinus tracts (SSTs). METHODS: This was a prospective analysis study conducted on the patients (n = 26) with SSTs underwent an innovative repairing surgery in Qilu Hospital of Shandong University, China between December 2015 and December 2020. The repairing surgery was GMMFs combined with RPSFs. The demographic information and the clinical parameters including operative time, postoperative healing time, and recurrence rate were used to evaluate the efficacy of the operation. RESULTS: Except one case of partial necrosis at the edge of the flap due to severe fibrosis, which was cured after dressing change, all the other cases showed effective healing after the operation. CONCLUSION: The combined application of GMMFs and RPSFs for the treatment of sacrococcygeal sinus tracts gains the advantages of short operative time, quick postoperative recovery, and low postoperative recurrence rate.

Intramuscular Neural Distribution of the Gluteus Maximus Muscle: Diagnostic Electromyography and Injective Treatments.

INTRODUCTION: The purpose of this study was to investigate neural patterns within the gluteus maximus (Gmax) muscle to identify optimal EMG placement and injection sites for botulinum toxin and other injectable agents. METHODS: This study used 10 fixed and 1 non-fixed adult Korean cadavers. Intramuscular arborization patterns were confirmed in the cranial, middle, and caudal segments of 20 Gmax muscles using Sihler staining. Ultrasound images were obtained from one cadaver, and blue dye was injected using ultrasound guidance to confirm the results. RESULTS: The intramuscular innervation pattern of the Gmax was mostly in the middle part of this muscle. The nerve endings of the Gmax are mainly located in the 40-70% range in the cranial segment, the 30-60% range in the middle segment, and the 40-70% range in the caudal segment. DISCUSSION: Addressing the spasticity of the gluteus maximus requires precise, site-specific botulinum toxin injections. The use of EMG and other injection therapies should be guided by the findings of this study. We propose that these specific sites, which correspond to areas with the densest nerve branches, are the safest and most efficient locations for both botulinum toxin injections and EMG procedures.

Deep Learning-Based Fully Automated Segmentation of Regional Muscle Volume and Spatial Intermuscular Fat Using CT.

RATIONALE AND OBJECTIVES: We aim to develop a CT-based deep learning (DL) system for fully automatic segmentation of regional muscle volume and measurement of the spatial intermuscular fat distribution of the gluteus maximus muscle. MATERIALS AND METHODS: A total of 472 subjects were enrolled and randomly assigned to one of three groups: a training set, test set 1, and test set 2. For each subject in the training set and test set 1, we selected six slices of the CT images as the region of interest for manual segmentation by a radiologist. For each subject in test set 2, we selected all slices of the gluteus maximus muscle on the CT images for manual segmentation. The DL system was constructed using Attention U-Net and the Otsu binary thresholding method to segment the muscle and measure the fat fraction of the gluteus maximus muscle. The segmentation results of the DL system were evaluated using the Dice similarity coefficient (DSC), Hausdorff distance (HD), and the average surface distance (ASD) as metrics. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to assess agreement in the measurements of fat fraction between the radiologist and the DL system. RESULTS: The DL system showed good segmentation performance on the two test sets, with DSCs of 0.930 and 0.873, respectively. The fat fraction of the gluteus maximus muscle measured by the DL system was in agreement with the radiologist (ICC=0.748). CONCLUSION: The proposed DL system showed accurate, fully automated segmentation performance and good agreement with the radiologist at fat fraction evaluation, and can be further used for muscle evaluation.

Gluteus Maximus Muscle Flap in Tongue in Groove and Wrap Around Pattern for Refractory CSF Leakage in Extradural Cyst Patient.

Spinal extradural arachnoid cyst (SEAC) is a rare disease and has surgical challenges because of the critical surrounding anatomy. We describe the rare case of a 58-year-old woman who underwent extradural cyst total excision with dural repair and presented with refractory cerebrospinal fluid (CSF) leakage even though two consecutive surgeries including dural defect re-repair and lumbar-peritoneal shunt were performed. The authors covered the sacral defect using bilateral gluteus maximus muscle flap in tongue in groove and wrap around pattern for protection of visible sacral nerve roots and blockage of CSF leakage point. With the flap coverage, the disappearance of cyst and fluid collection was confirmed in the postoperative radiological finding, and the clinical symptoms were significantly improved. By protecting the sacral nerve roots and covering the base of sacral defect, we can minimize the risk of complication and resolve the refractory fluid collection. Our results suggest that the gluteus muscle flap can be a safe and effective option for sacral defect and CSF leakage in extradural cyst or other conditions.

Endoscopic gluteus maximus tendon release for external snapping hip syndrome: a functional assessment.

PURPOSE: The aim of this retrospective study was to investigate the clinical follow-up of patients with external snapping hip syndrome (ESHS) treated with endoscopic gluteus maximus tendon release and to compare the residual muscular strength and thigh circumference as an indirect outcome measure. METHODS: Patients of all ages with external snapping hip syndrome were treated with endoscopic gluteus maximus tendon release. Outcome measures evaluated included: visual analog scale (VAS), modified Harris Hip Score (mHHS), and Non-Arthritic Hip Score (NAHS). The gluteus maximus strength and the circumference of the thigh were also evaluated. RESULTS: Among 25 patients, 23 fulfilled the inclusion criteria and one patient was lost to follow-up. The series included 22 patients, 6 males and 16 females with a mean age of 27.9 ± 13.4 years (range 16-76 years). All patients had resolution of the snapping symptoms after the procedure. The mean follow-up was 18 ± 9.3 months. All outcomes improved in a statistically significant manner: VAS value decreased from 6.8 (range 6-8) to 0.6 (range 0-4) (p < 0.001), mHHS increased from 48.6 (range 17.6-67) to 88.2 (range 67-94.6) (p < 0.001), NAHS increased from 49.0 (range 21.5-66) to 90.8 (range 66-98.75) (p < 0.001). A statistically significant reduction of operated limb thigh circumference compared to the contralateral side (3.7%) was also found, while there were no statistical differences regarding the strength of gluteus maximus muscles. CONCLUSIONS: Endoscopic gluteus maximus tendon release is an excellent surgical option to treat snapping hip syndrome. The evaluated muscle strength revealed no functional impairment. The significance of the limb circumference reduction has yet to be determined. LEVEL OF EVIDENCE: IV: retrospective comparative trial.

Gluteoperinealis muscle: a surgically important variation.

BACKGROUND: Anatomical variations are common in gluteal region. This report presents two cases of gluteoperinealis muscles detected during radiological imaging. CASE PRESENTATION: Our study was conducted on two patients. This report describes an accessory muscle detected in the gluteal region on MRI examination of a patient who admitted to our clinic after a firearm injury and a second patient examined with CT imaging who had signs of pelvic infection. In the first case, this accessory muscle originated bilaterally from the fascia of the gluteus maximus throughout its posteromedial side and was attached to the perineal body. In the second case, it extended forward from the fascia of the gluteus maximus muscle and inserted to the cavernous body of penis on the left side and to the perineal body on the right. In the literature, this accessory muscle has been described as the gluteoperinealis muscle being a rare variation. CONCLUSION: Considering the origin and insertion of the muscle, this variation may be important during the surgical operations of the gluteal and perineal regions.

The study of the lower limb entheses in the Neanderthal sample from El Sidrón (Asturias, Spain): How much musculoskeletal variability did Neanderthals accumulate?

Entheses have rarely been systematically studied in the field of human evolution. However, the investigation of their morphological variability (e.g., robusticity) could provide new insight into their evolutionary significance in the European Neanderthal populations. The aim of this work is to study the entheses and joint features of the lower limbs of El Sidrón Neanderthals (Spain; 49 ka), using standardized scoring methods developed on modern samples. Paleobiology, growth, and development of both juveniles and adults from El Sidrón are studied and compared with those of Krapina Neanderthals (Croatia, 130 ka) and extant humans. The morphological patterns of the gluteus maximus and vastus intermedius entheses in El Sidrón, Krapina, and modern humans differ from one another. Both Neanderthal groups show a definite enthesis design for the gluteus maximus, with little intrapopulation variability with respect to modern humans, who are characterized by a wider range of morphological variability. The gluteus maximus enthesis in the El Sidrón sample shows the osseous features of fibrous entheses, as in modern humans, whereas the Krapina sample shows the aspects of fibrocartilaginous ones. The morphology and anatomical pattern of this enthesis has already been established during growth in all three human groups. One of two and three of five adult femurs from El Sidrón and from Krapina, respectively, show the imprint of the vastus intermedius, which is absent among juveniles from those Neanderthal samples and in modern samples. The scant intrapopulation and the high interpopulation variability in the two Neanderthal samples is likely due to a long-term history of small, isolated populations with high levels of inbreeding, who also lived in different ecological conditions. The comparison of different anatomical entheseal patterns (fibrous vs. fibrocartilaginous) in the Neanderthals and modern humans provides additional elements in the discussion of their functional and genetic origin.

Surgical treatment of middle cluneal nerve entrapment neuropathy: technical note.

OBJECTIVE The etiology of low-back pain (LBP) is heterogeneous and is unknown in some patients with chronic pain. Superior cluneal nerve entrapment has been proposed as a causative factor, and some patients suffer severe symptoms. The middle cluneal nerve (MCN) is also implicated in the elicitation of LBP, and its clinical course and etiology remain unclear. The authors report the preliminary outcomes of a less invasive microsurgical release procedure to address MCN entrapment (MCN-E). METHODS The authors enrolled 11 patients (13 sites) with intractable LBP judged to be due to MCN-E. The group included 3 men and 8 women ranging in age from 52 to 86 years. Microscopic MCN neurolysis was performed under local anesthesia with the patient in the prone position. Postoperatively, all patients were allowed to walk freely with no restrictions. The mean follow-up period was 10.5 months. LBP severity was evaluated on the numerical rating scale (NRS) and by the Japanese Orthopaedic Association (JOA) and the Roland-Morris Disability Questionnaire (RDQ) scores. RESULTS All patients suffered buttock pain, and 9 also had leg symptoms. The symptoms were aggravated by standing, lumbar flexion, rolling over, prolonged sitting, and especially by walking. The numbers of nerve branches addressed during MCN neurolysis were 1 in 9 patients, 2 in 1 patient, and 3 in 1 patient. One patient required reoperation due to insufficient decompression originally. There were no local or systemic complications during or after surgery. Postoperatively, the symptoms of all patients improved statistically significantly; the mean NRS score fell from 7.0 to 1.4, the mean RDQ from 10.8 to 1.4, and the mean JOA score rose from 13.7 to 23.6. CONCLUSIONS Less invasive MCN neurolysis performed under local anesthesia is useful for LBP caused by MCN-E. In patients with intractable LBP, MCN-E should be considered.

Comparative study between fasciocutaneous and myocutaneous flaps in the surgical treatment of pressure ulcers of the sacral region.

INTRODUCTION: Decubitus ulcers of the sacral region are common conditions in bedridden patients. Deep lesions (Stages III and IV) often require surgical treatment for closure. Flaps of the region are the first choice for treatment. We present our experience in the treatment of these lesions and compare two different approaches: local fasciocutaneous flap and gluteus maximus myocutaneous flap with V-Y advancement. METHOD: From March 2009 to May 2014, 32 patients underwent closure of sacral pressure ulcers by flaps, 17 of them with rotational local fasciocutaneous flaps and 15 with myocutaneous flaps of the gluteus maximus muscle with V-Y advancement. Evolution regarding complications and rate of success after two months was compared between the groups. RESULTS: Out of the 32 operated patients we obtained resolution of lesions after two months in 23 (71.8%), 10 patients in the fasciocutaneous flap group (58.8%) and 13 cases in the myocutaneous flap group (86.6%). The most common complication was partial dehiscence of sutures in 12 patients (37.5%), 8 patients in the fasciocutaneous flap group (47%) and 4 patients in the myocutaneous flap group (26.6%). The group of patients reconstructed with local fasciocutaneous flaps presented 3 cases with seroma, one with hematoma and 6 with partial cutaneous necrosis; these patients also required more drainage time. CONCLUSIONS: Both the local rotational fasciocutaneous flap and the myocutaneous flap of the gluteus maximus muscle in V-Y flap can be used in the surgical treatment of sacral ulcers. In our experience, a reduced success rate and more complications were found in the local fasciocutaneous reconstructive method.

Foetal development of the human gluteus maximus muscle with special reference to its fascial insertion.

The human gluteus maximus muscle (GMX) is characterised by its insertion to the iliotibial tract (a lateral thick fascia of the thigh beneath the fascia lata), which plays a critical role in lateral stabilisation of the hip joint during walking. In contrast, in non-human primates, the GMX and biceps femoris muscle provide a flexor complex. According to our observations of 15 human embryos and 11 foetuses at 7-10 weeks of gestation (21-55 mm), the GMX anlage was divided into 1) a superior part that developed earlier and 2) a small inferior part that developed later. The latter was adjacent to, or even continuous with, the biceps femoris. At 8 weeks, both parts inserted into the femur, possibly the future gluteal tuberosity. However, depending on traction by the developing inferior part as well as pressure from the developing major trochanter of the femur, most of the original femoral insertion of the GMX appeared to be detached from the femur. Therefore, at 9-10 weeks, the GMX had a digastric muscle-like appearance with an intermediate band connecting the major superior part to the small inferior mass. This band, most likely corresponding to the initial iliotibial tract, extended laterally and distally far from the muscle fibres. The fascia lata was still thin and the tensor fasciae latae seemed to develop much later. It seems likely that the evolutionary transition from quadripedality to bipedality and a permanently upright posture would require the development of a new GMX complex with the iliotibial tract that differs from that in non-human primates. (Folia Morphol 2018; 77, 1: 144-150).

Application of split gluteus maximus muscle--adipofascial turnover flap and subcutaneous tension-reducing suture technique in repair of decubitus ulcers.

The purpose of this study was to study the clinical effect of split gluteus maximus muscle-adipofascial turnover flap and tension-reducing suture in the treatment of decubitus ulcers. Thirty-one cases of sacrococcygeal decubitus ulcers were repaired by split gluteus maximus muscle-adipofascial turnover flap. The surface of flaps ranged from 5×6 cm to 7×8 cm. The skin was then closed, primarily using subcutaneous tension-reducing suture. Eighty-eight percent of the flaps (27 of 31) healed primarily. The split gluteus maximus muscle-adipofascial turnover flap and tension-reducing suture technique was found to be a highly efficient method of repairing decubitus ulcers with a relatively low ratio of recurrence.

An unusual cause of external snapping hip.

The external snapping hip syndrome is a condition characterized by palpable or audible snap on the lateral region of the hip occurring during movements and sometimes associated with pain. It is typical of young adults and athletes and can be favored by the abnormal sliding of the iliotibial band or of the gluteus maximus muscle over the greater trochanter. We present a case of external snapping hip syndrome occurring in a young woman secondary to a dysmorphic sickle-shaped myotendinous junction of the gluteus maximus muscle. Diagnosis was allowed by an integrated clinical and radiological approach, based on dynamic ultrasound and magnetic resonance imaging (MRI).