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Deep gluteal syndrome: anatomy, imaging, and management of sciatic nerve entrapments in the subgluteal space. Skeletal Radiol. DOI 10.1007/s00256-015-2124-6
Abstract
Deep gluteal syndrome (DGS) is an underdiagnosed
entity characterized by pain and/or dysesthesias in
the buttock area, hip or posterior thigh and/or radicular pain
due to a non-discogenic sciatic nerve entrapment in the
subgluteal space. Multiple pathologies have been incorporated
in this all-included Bpiriformis syndrome,^ a term that has
nothing to do with the presence of fibrous bands, obturator
internus/gemellus syndrome, quadratus femoris/ischiofemoral
pathology, hamstring conditions, gluteal disorders and orthopedic
causes. The concept of fibrous bands playing a role in
causing symptoms related to sciatic nerve mobility and entrapment
represents a radical change in the current diagnosis of
and therapeutic approach to DGS. The development of
periarticular hip endoscopy has led to an understanding of
the pathophysiological mechanisms underlying piriformis
syndrome, which has supported its further classification. A
broad spectrum of known pathologies may be located nonspecifically
in the subgluteal space and can therefore also trigger
DGS. These can be classified as traumatic, iatrogenic, inflammatory/
infectious, vascular, gynecologic and tumors/pseudotumors.
Because of the ever-increasing use of advanced magnetic
resonance neurography (MRN) techniques and the excellent
outcomes of the new endoscopic treatment, radiologists
must be aware of the anatomy and pathologic conditions
of this space. MR imaging is the diagnostic procedure of
choice for assessing DGS and may substantially influence
the management of these patients. The infiltration test not only
has a high diagnostic but also a therapeutic value. This article
describes the subgluteal space anatomy, reviews known and
new etiologies of DGS, and assesses the role of the radiologist
in the diagnosis, treatment and postoperative evaluation of
sciatic nerve entrapments, with emphasis on MR imaging
and endoscopic correlation.
... Recent advances in imaging, especially MR neurography and treatments, have aided this diagnostic process. Deep gluteal syndrome is a term used to describe entrapment neuropathy in sub-gluteal space, which presents with chronic gluteal pain and/or radiculopathy (Hernando et al. 2015;Koh 2021). There are multiple causes for this nerve entrapment with piriformis syndrome being one of the causes for deep gluteal syndrome (Hernando et al. 2015). ...
... Deep gluteal syndrome is a term used to describe entrapment neuropathy in sub-gluteal space, which presents with chronic gluteal pain and/or radiculopathy (Hernando et al. 2015;Koh 2021). There are multiple causes for this nerve entrapment with piriformis syndrome being one of the causes for deep gluteal syndrome (Hernando et al. 2015). This chapter deals with the background, role of dynamic positioning in its causation, various etiologies, clinical presentations, diagnostic algorithm of deep gluteal syndrome with emphasis on MR neurography, and management of such conditions. ...
... The piriformis muscle divides this space into suprapiriformis space and infrapiriformis space. Superior gluteal artery and nerve run within the suprapiriformis space, while inferior gluteal artery/nerve, sciatic nerve, posterior femoral cutaneous nerve, and nerves to obturator internus/gemellus superior and quadratus femoris/gemellus inferior nerves run within the infrapiriformis space (Hernando et al. 2015). The connective tissues including sacrospinous and sacrotuberous ligaments and fascial layers provide structural support and contribute to the overall stability of the region. ...
Deep gluteal syndrome is a type of entrapment neuropathy of the deep gluteal space where patients present with chronic buttock pain and/numbness with or without sciatica. Piriformis syndrome is one of the etiologies of deep gluteal syndrome wherein there is suspected compression of static or dynamic sciatic nerve due to the piriformis muscle and its variations. Good clinical history and examination can help in raising the clinical suspicion for deep gluteal syndrome. Imaging not only aids in the diagnosis but also has a large role in the treatment of this condition. MR neurography is an indispensable aid for the diagnosis of neuromuscular alterations associated with this syndrome. During evaluation of the deep gluteal syndrome, discogenic etiology for sciatica needs to be excluded as well. Conservative management includes medications for pain relief and muscle relaxation and physiotherapy. Image-guided interventions like intramuscular Botox injection and perineural sciatic injection can provide longer term relief. Patients with a history of failed conservative management and image-guided interventions can be considered for surgical intervention. Timely diagnosis of deep gluteal syndrome can help guide patient management and avoid unnecessary procedures.
... 1 Clinically, patients present with posteromedial pain at the root of the lower limb, frequently associated with radiation of pain to the thigh or buttocks. 8 Although it is true that some authors describe the clinical symptoms as hip pain, 2,4,5 it is common for patients to refer to it as gluteal pain, and it is currently included in the literature within the syndromes of the deep glutei. [8][9][10] The pain can worsen with external rotation, adduction and extension of the hip. ...
... 8 Although it is true that some authors describe the clinical symptoms as hip pain, 2,4,5 it is common for patients to refer to it as gluteal pain, and it is currently included in the literature within the syndromes of the deep glutei. [8][9][10] The pain can worsen with external rotation, adduction and extension of the hip. This limits hip movement, with walking and sitting being especially poorly tolerated, as we observed in some of our cases included in the series. ...
... As a result, patients frequently seek an analgesic position. 8 Acute symptoms can develop (due to the accumulation of oedema and inflammation in the anatomical structures included) or chronic symptoms (due to the appearance of fibrous tissue that traps the sciatic nerve), evolving over months or even years. 8,9 A differential diagnosis should be reached with pathologies that produce similar symptoms, such as psoas tendon rupture, lumbar radiculopathy, hamstring or adductor tendinopathy, or quadratus femoris rupture, as well as the causes of groin pain: bursitis and osteitis of the hip, synphysitis, entrapment of the sciatic nerve or pudendal nerve, among others. ...
Gluteal pain is a frequent cause of medical attention in the daily clinical practice. It can be caused by multiple pathologies, being ischiofemoral impingement syndrome among those included in its differential diagnosis. Encompassed within the deep gluteal syndromes, this entity occurs as a consequence of the entrapment of the neuromuscular structures between the lesser femoral trochanter and the ischial tuberosity, causing pain in the root of the lower limb, with irradiation towards the thigh or the gluteal region and poor tolerance to deambulation and sedestation. The magnetic resonance imaging of the hip is fundamental for its diagnosis, and its management consists on medical treatment at onset. Despite not being a frequent diagnosis in the clinical practice in Rheumatology, keeping it in mind helps improving its prognosis by establishing an early and adequate treatment.
... Clínicamente, los pacientes presentan dolor a nivel posteromedial en la raíz del miembro inferior, asociando con frecuencia irradiación del dolor hacia el muslo o hacia el glúteo 8 . Si bien es cierto que algunos autores describen la clínica como dolor de cadera 2,4,5 , es habitual que los pacientes lo refieran como un dolor glúteo, englobándose actualmente en la literatura dentro de los síndromes de glúteo profundo [8][9][10] . El dolor puede empeorar con la rotación externa, la aducción y la extensión de la cadera, limitando sus movimientos, siendo especialmente mal toleradas la marcha y la sedestación, tal y como observamos en algunos de nuestros casos incluidos en la serie. ...
... El dolor puede empeorar con la rotación externa, la aducción y la extensión de la cadera, limitando sus movimientos, siendo especialmente mal toleradas la marcha y la sedestación, tal y como observamos en algunos de nuestros casos incluidos en la serie. Esto hace que los pacientes busquen con frecuencia una posición antiálgica 8 . Puede desarrollarse un cuadro agudo (por acúmulo de edema e inflamación en las estructuras anatómicas incluidas) o crónico (debido a la aparición de tejido fibroso que atrapa al nervio ciático), evolucionando durante meses o incluso años 8,9 . ...
... La resonancia magnética (RM) de cadera es la prueba de referencia para observar la disminución del espacio isquiofemoral 12 ( fig. 1). Se considera la existencia de pinzamiento cuando el espacio isquiofemoral es menor de 23 (± 8) cm, o bien cuando la anchura del músculo cuadrado femoral es menor de 12 (± 4) cm 5,8 . No obstante, existe controversia con el uso de estos valores de referencia 1,11 , dado que este espacio es muy variable según el ciclo de la marcha y la posición del paciente durante la prueba de imagen, y además la RM suele sobreestimar su medida, por lo que la exploración física del paciente resulta fundamental en el diagnóstico de esta patología. ...
El dolor glúteo es un motivo frecuente de consulta médica en la práctica clínica diaria. Las causas son muy
variadas, pudiendo encontrar entre aquellas que forman parte de su diagnóstico diferencial el síndrome
de pinzamiento isquiofemoral. Este, incluido actualmente dentro de los síndromes de glúteo profundo, es
consecuencia del atrapamiento de las estructuras neuromusculares englobadas entre el trocánter menor
y la tuberosidad isquiática, lo que ocasiona un cuadro de dolor en la raíz del miembro inferior, con irradiación
hacia el muslo o hacia la región glútea, y mala tolerancia a la deambulación y a la sedestación. La
prueba diagnóstica fundamental es la resonancia magnética de cadera, y su manejo suele ser médico inicialmente.
A pesar de no ser una entidad frecuente en las consultas de reumatología, tener esta patología
en mente ayuda a mejorar su pronóstico, al poder ofrecer un tratamiento adecuado y precoz.
... At this level, the SN is protected from the sacrum by the pyramidalis muscle, and more caudally from the ischium by the superior gemellus and inferior gemellus muscles, the obturator internus muscle, and the quadratus femoris muscle (▶ Fig. 3). [4] Interestingly, the superior gemellus, inferior gemellus, and obturator internus are collectively defined as the triceps coxae. The segment of the SN located in the deep gluteal space normally shows a (gentle) curvilinear shape to wrap the muscle belly of the triceps coxae after exiting from the infrapiriform foramen [5]. ...
... At this level, by shifting the probe more distally, a thick hyperechoic interfascial plane can be easily observed and used as an anatomical landmark to promptly differentiate the quadratus femoris muscle from the inferior gemellus muscle (▶ Fig. 4C). For sure, several anatomical variations can be encountered in clinical practice with a single SN or multiple neural branches traveling within the infrapiriform foramen, the suprapiriform foramen, and inside the muscle belly of the piriformis muscle as well [4,8]. Interestingly, bending of the SN in the deep gluteal space can also be related to hip internal rotation and isometric contraction of the triceps coxae, due to the presence of a connective anchorage between the nerve and the obturator internus tendoni. ...
... e269 b Elektronischer Sonderdruck zur persönlichen Verwendung surgery, tendon avulsion, tendinosis, muscle strains, calcific tendinopathy, and muscle spasm are the most common causes of this syndrome. [4] Indeed, the authors suggest fully scrutinizing the piriformis muscle-tendon unit starting from its proximal muscular portion until its most distal tendinous component attaching to the bony surface of the greater trochanter [19]. Moreover, dynamic scanning with the patient in a prone position should be performed by matching hip internal rotation (i. ...
The sciatic nerve (SN) is the biggest nerve in the human body and innervates a large skin surface of the lower limb and several muscles of the thigh, leg, and foot. It originates from the ventral rami of spinal nerves L4 through S3 and contains fibers from both the posterior and anterior divisions of the lumbosacral plexus. After leaving the neural foramina, the nerve roots merge with each other forming a single peripheral nerve that travels within the pelvis and thigh. Non-discogenic pathologies of the SN are largely underdiagnosed entities due to nonspecific clinical tests and poorly described imaging findings. Likewise, to the best of our knowledge, a step-by-step ultrasound protocol to assess the SN is lacking in the pertinent literature. In this sense, the aim of the present manuscript is to describe the normal sono-anatomy of the SN from the greater sciatic foramen to the proximal thigh proposing a standardized and simple sonographic protocol. Then, based on the clinical experience of the authors, a few tips and tricks have been reported to avoid misinterpretation of confounding sonographic findings. Last but not least, we report some common pathological conditions encountered in daily practice with the main purpose of making physicians more confident regarding the sonographic “navigation” of a complex anatomical site and optimizing the diagnosis and management of non-discogenic neuropathies of the SN.
... The trajectory of the sciatic nerve takes it through the subgluteal space, a region encompassed by the gluteal aponeuroses. This space spans from the upper border of the piriformis muscle to the lower margin of the gluteus maximus muscle [57]. Within this context, deep gluteal syndrome (DGS) manifests as an entrapment neuropathy occurring within the subgluteal space, encompassing conditions such as piriformis syndrome [57,58]. ...
... This space spans from the upper border of the piriformis muscle to the lower margin of the gluteus maximus muscle [57]. Within this context, deep gluteal syndrome (DGS) manifests as an entrapment neuropathy occurring within the subgluteal space, encompassing conditions such as piriformis syndrome [57,58]. Other contributors to DGS encompass obturator internus/ gemellus syndrome, ischiofemoral impingement, hamstring tendinopathy, and various gluteal disorders. ...
Magnetic resonance neurography (MRN) is increasingly used to visualize peripheral nerves in vivo. However, the implementation and interpretation of MRN in the brachial and lumbosacral plexi are challenging because of the anatomical complexity and technical limitations. The purpose of this article was to review the clinical context of MRN, describe advanced magnetic resonance (MR) techniques for plexus imaging, and list the general categories of utility of MRN with pertinent imaging examples. The selection and optimization of MR sequences are centered on the homogeneous suppression of fat and blood vessels while enhancing the visibility of the plexus and its branches. Standard 2D fast spin-echo sequences are essential to assess morphology and signal intensity of nerves. Moreover, nerve-selective 3D isotropic images allow improved visualization of nerves and multiplanar reconstruction along their course. Diffusion-weighted and diffusion-tensor images offer microscopic and functional insights into peripheral nerves. The interpretation of MRN in the brachial and lumbosacral plexi should be based on a thorough understanding of their anatomy and pathophysiology. Anatomical landmarks assist in identifying brachial and lumbosacral plexus components of interest. Thus, understanding the varying patterns of nerve abnormalities facilitates the interpretation of aberrant findings.
... In these cases the differential diagnosis should be made with so-called deep gluteal syndrome, a syndrome characterised by pain and/or dysesthesia in the buttock, hip or posterior thigh, together with radicular pain due to impingement of the sciatic nerve, which is located posterior to the insertion of the gluteus maximus at a distance of 3-6 cm, in the subgluteal space. One of the causes of this is compressive fibrous bands running between the posterior surface of the greater trochanter and the gluteus maximus (14)(15)(16) . ...
50 RESUMEN Tratamiento endoscópico de tendinitis calcificante del glúteo mayor. A propósito de un caso La tendinitis calcificante es una patología frecuente; en cambio, su prevalencia y localización en el tendón del glúteo mayor es extremadamente rara y se dispone de escasa bibliografía sobre su tratamiento. Presentamos un caso de una mujer de 46 años que presentaba dolor en la región posterolateral de la cadera, junto con radiculopatía ipsilateral, secundarios a tendinitis cal-cificante del glúteo mayor. Debido a la gravedad, cronicidad y resistencia de los síntomas, se realizó intervención quirúrgica consistente en limpieza endoscópica intratendón. Los controles radiográficos postoperatorios demuestran una extirpación prác-ticamente completa. La paciente se mantiene asintomática y sin recurrencia al año de la intervención. Solo existe publicado un caso semejante a este con éxito similar. La endoscopia debe ser considerada como una opción de trata-miento eficaz frente a la tendinitis calcificante del glúteo mayor resistente al tratamiento conservador, presentando adicional-mente la menor morbilidad de la cirugía endoscópica con res-pecto a la cirugía abierta Palabras clave: Artroscopia. Cadera. Labrum. Calcificación. Glúteo mayor. ABSTRACT While calcific tendinitis is a common disorder, its prevalence and location in the gluteus maximus tendon is extremely rare, and there is little literature on its treatment. We present the case of a 46-year-old woman who presented with pain in the postero-lateral region of the hip, together with ipsilateral radiculopathy, secondary to calcific tendinitis of the gluteus maximus. Due to the severity, chronicity and resistance of the symptoms, surgery consisting of endoscopic intratendon cleaning was decided. The postoperative radiographic examinations demonstrate virtually complete excision. The patient remains asymptomatic and without recurrence one year after surgery. There is only a single previous published case similar to this one, reporting similar success. Endoscopy should be considered as an effective treatment option for calcific tendinitis of the gluteus maximus resistant to conservative management, with the additional advantage of the lesser morbidity of endoscopic surgery compared to open surgery .
... También se han descrito casos de dolor ciático junto a test de tensión neural positivo (test de Slump sentado) (8,12,13) y en estos casos debe realizarse el diagnóstico diferencial con el denominado síndrome glúteo profundo, síndrome caracterizado por dolor y/o disestesias en la nalga, la cadera o la cara posterior del muslo, junto con dolor radicular debido a un atrapamiento del nervio ciático, el cual se encuentra localizado posterior a la inserción del glúteo mayor a una distancia de 3 a 6 cm, en el espacio subglúteo. Una de las causas de este son bandas fibrosas compresivas que discurren entre la cara posterior del trocánter mayor y el glúteo mayor (14)(15)(16) . ...
RESUMEN La tendinitis calcificante es una patología frecuente; en cambio, su prevalencia y localización en el tendón del glúteo mayor es extremadamente rara y se dispone de escasa bibliografía sobre su tratamiento. Presentamos un caso de una mujer de 46 años que presentaba dolor en la región posterolateral de la cadera, junto con radiculopatía ipsilateral, secundarios a tendinitis calcificante del glúteo mayor. Debido a la gravedad, cronicidad y resistencia de los síntomas, se realizó intervención quirúrgica consistente en limpieza endoscópica intratendón. Los controles radiográficos postoperatorios demuestran una extirpación prácticamente completa. La paciente se mantiene asintomática y sin recurrencia al año de la intervención. Solo existe publicado un caso semejante a este con éxito similar. La endoscopia debe ser considerada como una opción de trata-miento eficaz frente a la tendinitis calcificante del glúteo mayor resistente al tratamiento conservador, presentando adicionalmente la menor morbilidad de la cirugía endoscópica con res-pecto a la cirugía abierta Palabras clave: Artroscopia. Cadera. Labrum. Calcificación. Glúteo mayor. ABSTRACT Endoscopic treatment of calcific tendinitis of the gluteus maximus. A case report While calcific tendinitis is a common disorder, its prevalence and location in the gluteus maximus tendon is extremely rare, and there is little literature on its treatment. We present the case of a 46-year-old woman who presented with pain in the postero-lateral region of the hip, together with ipsilateral radiculopathy, secondary to calcific tendinitis of the gluteus maximus. Due to the severity, chronicity and resistance of the symptoms, surgery consisting of endoscopic intratendon cleaning was decided. The postoperative radiographic examinations demonstrate virtually complete excision. The patient remains asymptomatic and without recurrence one year after surgery. There is only a single previous published case similar to this one, reporting similar success. Endoscopy should be considered as an effective treatment option for calcific tendinitis of the gluteus maximus resistant to conservative management, with the additional advantage of the lesser morbidity of endoscopic surgery compared to open surgery.
... This study showed including hip strengthening exercises is very effective in treating piriformis syndrome. In studies we have seen patients with piriformis syndrome who responded well when focused on strengthening of hip muscles and correcting gait patterns, clinically significant improvements were reported in piriformis syndrome, physiotherapy procedures must include strengthening hip muscle along with other techniques [14,15]. In current study, result showed that group A which received the treatment of hip abductor strengthening and sciatic nerve gliding exercise showed significant results as compared to group B which received piriformis stretching. ...
Background: Piriformis syndrome is a neuromuscular disorder where the sciatic nerve is compressed or irritated by the inflammation of piriformis muscle representing pain, tingling and numbness in the buttock region and in the course of sciatic nerve. Piriformis syndrome can be painful, but it is very rarely alarming and needs surgical interventions. It can be managed effectively by conservative means such as NSAIDS, analgesics and physiotherapy interventions like stretching, electro therapeutic modalities, myofascial release, thermo therapies, etc. The purpose of this study is to compare the effect of sciatic nerve gliding exercise with hip abductor strengthening exercises versus piriformis stretching exercises in software professionals who are sitting for prolong hours in office and diagnosed with piriformis syndrome. Materials & Methods: 30 patients with piriformis syndrome, reporting at the OPD of Physiotherapy Department were evaluated according to the inclusion and exclusion criteria and were divided into Group A (experimental) N=15, Group B (control) N=15 randomly. Their baseline data with respect to age, sex, pain in VAS, hip internal rotation range by goniometer, and disability evaluation by MODQ were taken on day 1 of the treatment and day 15 of the treatment. Data analysis was done by Mann Whitney ‘u’ test for subjective data and unpaired ‘t’ test for objective data analysis with 95%confidence interval. Results: The patients treated with sciatic nerve sliding exercise and abductor strengthening (Group A) showed statistically significant decrease in pain (p=0.00), increase in range of motion for hip internal rotation (p=0.00) and decrease in disability level according to MODQ (p=0.00) after 15 days of interventions as compared to Group B who were treated by piriformis stretching exercises. Conclusion: This study has shown significant improvement in the experimental group (group A) in respect to pain relief, hip internal rotation range of motion, and .......
... 1 It unites such syndromes as "sciatic neuropathy," "infrapiriformis space syndrome," "piriformis muscle syndrome," "obturator internus/gemellus syndrome," and "quadratus femoris/ ischiofemoral pathology." 2 In case of conservative treatment failure, surgical intervention is performed with sciatic nerve decompression. Endoscopic decompression is much less traumatic than open techniques and is gaining more and more popularity. ...
We describe all-endoscopic deep gluteal syndrome treatment and sciatic nerve decompression at the infrapiriformis space. Surgery is performed with the patient in the prone position with the usual arthroscopic instruments and pump. The first step includes performing placement of 2 initial portals (medial and median) without fluoroscopy in the area of the ischial tuberosity and conjoint tendon, as well as release in this area with a subsequent shift in the lateral direction. The second step includes performing placement of an additional lateral portal for instruments, switching the camera into the median portal, and visualizing the sciatic nerve and its decompression at the infrapiriformis space and upper part of the thigh area. The postoperative period includes early activation, immediate passive and active motion after surgery, and full weight bearing the day after surgery.
Object:
Extraspinal sciatica can present unique challenges in clinical diagnosis and management. In this study, the authors evaluated qualitative and quantitative patterns of sciatica-related pathology at the ischial tuberosity on MR neurography (MRN) studies performed for chronic extraspinal sciatica.
Methods:
Lumbosacral MRN studies obtained in 14 patients at the University of California, San Francisco between 2007 and 2011 were retrospectively reviewed. The patients had been referred by neurosurgeons or neurologists for chronic unilateral sciatica (≥ 3 months), and the MRN reports described asymmetrical increased T2 signal within the sciatic nerve at the level of the ischial tuberosity. MRN studies were also performed prospectively in 6 healthy volunteers. Sciatic nerve T2 signal intensity (SI) and cross-sectional area at the ischial tuberosity were calculated and compared between the 2 sides in all 20 subjects. The same measurements were also performed at the sciatic notch as an internal reference. Adjacent musculoskeletal pathology was compared between the 2 sides in all subjects.
Results:
Seven of the 9 patients for whom detailed histories were available had a specific history of injury or trauma near the proximal hamstring preceding the onset of sciatica. Eight of the 14 patients also demonstrated soft-tissue abnormalities adjacent to the proximal hamstring origin. The remaining 6 had normal muscles, tendons, and marrow in the region of the ischial tuberosity. There was a significant difference in sciatic nerve SI and size between the symptomatic and asymptomatic sides at the level of the ischial tuberosity, with a mean adjusted SI of 1.38 compared with 1.00 (p < 0.001) and a mean cross-sectional nerve area of 0.66 versus 0.54 cm(2) (p = 0.002). The control group demonstrated symmetrical adjusted SI and sciatic nerve size.
Conclusions:
This study suggests that chronic sciatic neuropathy can be seen at the ischial tuberosity in the setting of prior proximal hamstring tendon injury or adjacent soft-tissue abnormalities. Because hamstring tendon injury as a cause of chronic sciatica remains a diagnosis of exclusion, this distinct category of patients has not been described in the radiographic literature and merits special attention from clinicians and radiologists in the management of extraspinal sciatica. Magnetic resonance neurography is useful for evaluating chronic sciatic neuropathy both qualitatively and quantitatively, particularly in patients for whom electromyography and traditional MRI studies are unrevealing.
Recent advances in magnetic resonance (MR) imaging have revolutionized peripheral nerve imaging and made high-resolution acquisitions a clinical reality. High-resolution dedicated MR neurography techniques can show pathologic changes within the peripheral nerves as well as elucidate the underlying disorder or cause. Neurogenic pain arising from the nerves of the pelvis and lumbosacral plexus poses a particular diagnostic challenge for the clinician and radiologist alike. This article reviews the advances in MR imaging that have allowed state-of-the-art high-resolution imaging to become a reality in clinical practice.
To detect the variable relationship between sciatic nerve and piriformis muscle and make surgeons aware of certain anatomical features of each variation that may be useful for the surgical treatment of the piriformis syndrome.
The gluteal region of 147 Caucasian cadavers (294 limbs) was dissected. The anatomical relationship between the sciatic nerve and the piriformis muscle was recorded and classified according to the Beaton and Anson classification. The literature was reviewed to summarize the incidence of each variation.
The sciatic nerve and piriformis muscle relationship followed the typical anatomical pattern in 275 limbs (93.6 %). In 12 limbs (4.1 %) the common peroneal nerve passed through and the tibial nerve below a double piriformis. In one limb (0.3 %) the common peroneal nerve coursed superior and the tibial nerve below the piriformis. In one limb (0.3 %) both nerves penetrated the piriformis. In one limb (0.3 %) both nerves passed above the piriformis. Four limbs (1.4 %) presented non-classified anatomical variations. When a double piriformis muscle was present, two different arrangements of the two heads were observed.
Anatomical variations of the sciatic nerve around the piriformis muscle were present in 6.4 % of the limbs examined. When dissection of the entire piriformis is necessary for adequate sciatic nerve decompression, the surgeon should explore for the possible existence of a second tendon, which may be found either inferior or deep to the first one. Some rare, unclassified variations of the sciatic nerve should be expected during surgical intervention of the region.
Seven patients underwent release of the piriformis from the femur. Patients with residual symptoms after conservative treatment had dramatic relief of sciatica and 70% resumed customary work after surgery. Minimum followup was 31 montiis (average: 51 months). Early diagnosis can avoid prolonging ineffective empiric treatment and disability with satisfactory results achieved in most patients by conservative treatment and relief of sciatica in selected surgical cases.
With the expansion of endoscopically exploring various areas around the hip have come new areas to define. The area posterior to the hip joint, known as the subgluteal space or deep gluteal space (DGS), is one such area. This chapter will summarize the relevant anatomy and pathology commonly found in the DGS. It is hoped that this will allow the reader to further explore the area and treat the appropriate pathological areas.
Hip pathology and nonarthritic hip conditions have only recently been recognized as a cause of hip pain. In 2003, Ganz, Leunig and colleagues described the concept of femoroacetabular impingement (FAI) as a cause of hip pain and a mechanism for end-stage hip osteoarthritis. Ganz et al. also postulated that 70-90% of hip osteoarthritis is likely due to abnormal hip mechanics related to FAI, dysplasia, or other hip deformities. Over the past ten years, the treatment of these non-arthritic hip pathologies has grown dramatically, and has been estimated to grow by 15% each year. It is the largest segment of grown in sports medicine and orthopedics as a whole. However, no definitive reference yet exists on hip arthroscopy and hip joint preservation surgery. While books have been published on hip arthroscopy, these texts are limited to the technical aspects of the procedure and do not explore content related to hip joint preservation surgery. The scope of this book covers the basic science of hip pathology, anatomy, biomechanics, pathology, and treatment. It has put together up-to-date research and has invited opinion leaders in the field to contribute to the text. The book is focused on disease pathology and provides comprehensive information on each disease topic, which is followed by technique-driven chapters to provide surgeons a reference for any procedure related to non-arthritic conditions of the hip.
Purpose:
To evaluate continuity of the sacrotuberous ligament (STL) in normal and abnormal hamstring (HS) tendons on magnetic resonance (MR) images and to test the hypothesis that greater degrees of HS retraction are correlated with STL discontinuity.
Materials and methods:
The institutional review board approved this retrospective HIPAA-compliant study and waived informed consent. Control cohort comprised 33 patients (mean age, 54.1 years) without HS abnormalities at hip MR arthrography. Study cohort comprised 100 patients (mean age, 55.3 years) with HS abnormalities at pelvic or hip MR imaging. Two musculoskeletal radiologists independently assessed STL continuity with the ischium and semimembranosus (SM) and conjoined biceps femoris and semitendinosus (BF-ST) tendons and evaluated these tendons for tendinopathy, partial tear, or rupture. A third musculoskeletal radiologist measured retraction of ruptured tendons. Inter- and intraobserver agreement was calculated with weighted κ or intraclass correlation coefficients. HS abnormalities in the cohorts were compared with Mann-Whitney test. In patients with tendon rupture, relationships between qualitative (STL and HS attachments) and quantitative (tendon retraction measurements) data were analyzed with analysis of variance and linear regression with Bonferroni correction.
Results:
STL was continuous with ischium in all patients. In control patients, STL was always continuous with BF-ST but never continuous with SM. In study patients, BF-ST tendon alone, SM tendon alone, and both BF-ST and SM tendons showed abnormalities in 17, six, and 77 patients, respectively. HS rupture occurred in 24 patients; it involved BF-ST tendon alone in 13 patients and both BF-ST and SM tendons in 11. STL was continuous with BF-ST tendon in 12 patients and discontinuous in 12 patients. Retraction of BF-ST tendon (mean, 33 mm; range, 5-81 mm) was independently correlated with STL continuity with BF-ST (P = .0001) and SM (P = .0004) tendon rupture. Retraction was significantly greater (P ≤ 0.01) when STL was discontinuous and SM tendon was ruptured. Inter- and intraobserver agreement was very good or excellent in categorization of HS abnormalities and measurement of retraction.
Conclusion:
STL showed continuity with both ischium and BF-ST tendon but not SM tendon. In HS rupture, tendon retraction was significantly less when STL remained attached to BF-ST tendon.
The purpose of this study was to determine the diagnostic accuracy of the straight leg raise (SLR), active piriformis, and seated piriformis stretch tests in identifying individuals with sciatic nerve entrapment.
Thirty-three individuals (female = 25 and male = 8) with a mean age of 43 years (range 15-64; SD ± 11 years) were included in the study. Twenty-three subjects had endoscopic findings of sciatic nerve entrapment. Ten subjects without entrapment during endoscopic assessment were used as a control group. The results of the SLR, active piriformis, and seated piriformis stretch tests were retrospectively reviewed for each subject and compared between both groups. The accuracy of these tests for the endoscopic finding of sciatic nerve entrapment was determined by calculating the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio.
The SLR had sensitivity of 0.15, specificity of 0.95, positive likelihood ratio of 3.20, negative likelihood ratio of 0.90, and diagnostic odds ratio of 3.59. The active piriformis test had sensitivity of 0.78, specificity of 0.80, positive likelihood ratio of 3.90, negative likelihood ratio of 0.27, and diagnostic odds ratio of 14.40. The seated piriformis stretch test had sensitivity of 0.52, specificity of 0.90, positive likelihood ratio of 5.22, negative likelihood ratio of 0.53, and diagnostic odds ratio of 9.82. The most accurate findings were obtained when the results of the active piriformis test and seated piriformis stretch test were combined, with sensitivity of 0.91, specificity of 0.80, positive likelihood ratio of 4.57, negative likelihood ratio of 0.11, and diagnostic odds ratio of 42.00.
The active piriformis and seated piriformis stretch tests can be used to help identify patients with and without sciatic nerve entrapment in the deep gluteal region. LEVEL OF EVIDENCE: II.