Optimizing sciatic nerve exposure: Insights from a multicenter experience and review of the literature.

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Over a period of 13 years, the authors operated a total of 137 patients with sciatic nerve lesions, including traumatic injuries, compression syndromes, and tumors or tumor-like lesions. Of these, 98 (71.5%) were men and 39 (28.4%) were women, with ages ranging from 14 to 86 years (mean age: 43 years). The site of the injury was classified into three groups: 1) the upper third, corresponding to the gluteal region; 2) the middle third, involving the posterior compartment of the thigh, distal to the gluteal fold and proximal to the PF; and 3) the lower third, located within the PF ( Fig. 1 , Fig. 2 ). In cases involving more than one region, the site of the most extensive component was considered the primary location. Based on this classification, 68 (49.6%) injuries were located in the upper third, 51 (37.2%) injuries were located in the middle third, 13 (9.4%) injuries were located in the lower third, and 5 (3.6%) injuries shared more than one region. A total of 137 sciatic nerve injury cases were classified according to the etiology and anatomical level as follows: 1) Upper third (gluteal region): iatrogenic injuries in 25 cases (18.2%), blunt trauma following hip injury in 19 cases (13.8%), tumors in 7 cases (5.1%), ganglion cysts in 2 cases (1.4%), gunshot wounds in 8 cases (5.8%), compressive neuropathies in 6 cases (4.3%), and 1 case (0.7%) of stab injury. 2) Middle third (distal to the gluteal fold and proximal to the PF): tumors in 23 cases (16.7%), gunshot injuries in 20 cases (14.5%), stab injuries in 6 cases (4.3%), and iatrogenic injuries in 5 cases (3.6%). 3) Lower third (PF): blunt trauma in 5 cases (3.6%), tumors in 3 cases (2.1%), gunshot injuries in 5 cases (3.6%), compression in 1 case (0.7%), and post-irradiation neuritis in 1 case (0.7%). The surgical approaches used for lesions in the upper third included Stookey and its variant, TGA, and IGA. For the middle and lower thirds, the PMTA and PFA, respectively. The distribution was as follows: Stookey approach in 4 (2.9%) cases, TGA in 51 (37.2%) cases, IGA in 13 (9.4%) cases, PMTA in 51 (37.2%) cases, PFA in 13 (9.4%) cases, and combined approaches in 5 (3.6%) cases —Stookey plus PMTA in 1 case, Stookey plus PMTA and PFA in 1 case, TGA plus IGA in 1 case, IGA plus PMTA in 1 case, and PMTA plus PFA in 1 case—. In total, 137 patients underwent 132 single and 5 combined surgical approaches. Neither major (e.g., iatrogenic, vascular, etc.) nor minor (e.g., infections, wound dehiscence, seroma, etc.)) complications related with the approaches were encountered. To mention, as no pathology involved the intrapelvic segment of the SN, surgical access to this region was neither indicated nor undertaken. In all cases, the chosen approach provided adequate exposure of the SN without any major intra- or post-operative complications.

This is a retrospective multicenter study involving 7 hospitals across 6 countries: Hospital de Clínicas Dr. Manuel Quintela—Universidad de la República— in Montevideo, Uruguay; Hospital Universitario HM Regla y San Francisco in León, Spain; Centro Neurológico—The American British Cowdray Medical Center— in Mexico City, Mexico; Ospedale Santa María della Misericordia in Rovigio, Italy; Neurospinal Hospital, and Mediclinic Parkview Hospital in Dubai, United Arab Emirates; and Hospital de Clínicas José de San Martín—Universidad de Buenos Aires— in Buenos Aires, Argentina. Inclusion criteria included records of all patients diagnosed with SN pathology requiring surgery between 2005 and 2018. A total of 137 patients were included. A database was created containing epidemiological data, clinical diagnosis, location of the injury, and details of the surgical approach. Approaches analyzed included the Stookey and one variant with widening of the sciatic notch, transgluteal (TGA), infragluteal (IGA), posterior mid-thigh (PMTA) and popliteal fossa approach (PFA). The versatility of each approach was assessed in terms of surgical exposure goals, aesthetic and functional performance (mobility and comfort) outcomes, and overall complication rates. Additionally, a narrative literature review was performed using PubMed Central, NIH, Cochrane Library, LILACS, and Medline Plus databases.

SN injuries encompass a wide spectrum of etiologies, with traumatic leions in the gluteal region being the most common. In recent years, modifications of established surgical approaches have made it possible to expose the SN while minimizing morbidity, and optimizing postoperative recovery. Although the Stookey's approach allows broad exposure, its more invasive nature may not be necessary in all cases, instead TGA should be the preferred approach for lesions seated at the gluteal region. The IGA offers excellent access for proximal mid-gluteal lesions without significant muscle damage. The PMTA is ideal for distal lesions and provides a safe corridor with minimal morbidity. In cases of extensive trauma requiring complex reconstructions, combining approaches enhances visualization and facilitate reconstruction. We consider that a thorough understanding of the anatomy and anatomical relationships of the SN with surrounding structures in the pelvis, gluteal region, thigh and popliteal fossa is essential for improving surgical outcomes and avoiding complications.

Described by Stookey in 1920, this classic approach provides broad exposure of the most proximal extrapelvic segment of the SN in the gluteal region. The patient is positioned prone, and the incision extends from the upper segment of the sacroiliac joint to the greater trochanter, then curves downward to the inferior gluteal fold and turns medially in a question mark-shaped trajectory. Following the skin incision and subcutaneous dissection, the insertion of the gluteus maximus muscle (GMM) is detached and retracted medially to expose the gluteal portion of the SN and the greater sciatic notch ( Patil and Friedman, 2005 ; Henry, 1957 ; Stookey, 1920 , 1922 ; Seletz, 1946a , 1972a ). Fig. 3 shows the location of the SN and the relation with Stookey's approach at the buttock region. Fig. 3 Stookey's approach. Fig. 3 Stookey's approach. The TGA was originally described by von Langenbeck, modified by Kocher in the late 19th century, and later popularized by Moore in the 1950s for exposure during hip surgery. In recent years, several modifications have been introduced by peripheral nerve surgeons ( Patil and Friedman, 2005 ; Bonaddio et al., 2021 ; Seletz, 1972b ; Socolovsky and Masi, 2012 ; Socolovsky et al., 2011 ). The patient is placed in the prone position, and the skin incision —ranging from curvilinear to horizontal— is made between the ischial tuberosity and the greater trochanter, as the SN lies between these two bony landmarks in the gluteal region, approximately 10 cm lateral to the midline ( Franco et al., 2006 ). After dissection of the subcutaneous tissue, the GMM is exposed and bluntly separated along the direction of its fibers. Deep to the GMM the subgluteal space is accessed, where the SN and the inferior gluteal vessels can be identified, exiting the greater sciatic notch, from below the piriformis muscle and over the external rotator muscles of the hip ( Patil and Friedman, 2005 ; Socolovsky et al., 2011 ; Meena et al., 2021 ; Gecheva et al., 2024 ; Omer and Spinner, 1980 ; Son and Lee, 2022 ; Dützmann et al., 2012 ; Bailey et al., 2023 ). Fig. 4 shows the location of the SN and the relation with TGA at the buttock region. Fig. 4 Transgluteal approach. Fig. 4 Transgluteal approach. The IGA involves accessing the SN through the gluteal fold. The midline of the posterior thigh, the ischial tuberosity and greater trochanter serve as superficial anatomical landmarks to guide localization of the SN in deeper planes. The patient is in the prone position, and the incision is made along the gluteal fold. The underlying tissues are dissected to expose the inferior border of the GMM, which is reflected proximally. The SN is visualized deep to the hamstring muscles as it enters the proximal midline of the thigh. For improved exposure of the nerve, the hamstring muscles are retracted to the sides ( Patil and Friedman, 2005 ; Bonaddio et al., 2021 ; de Souza et al., 1987 ). Fig. 5 shows the location of the SN and the relation with IGA at the buttock and proximal thigh regions. Fig. 5 Infragluteal approach. Fig. 5 Infragluteal approach. Regardless of the level of the thigh, a posterior midline incision centered over the lesion, and extended proximally or distally as needed is commonly effective ( Moore, 1957 ). To approach the SN at the middle third of the thigh (PMTA), the patient is positioned prone, and a midline incision is made along the posterior aspect of the thigh. The subcutaneous tissues are then dissected, and both the superficial and deep aponeuroses are incised to access the posterior muscular compartment. The hamstring muscles are identified, with the SM and ST located medially, and the short and long head of the biceps femoris positioned laterally. The long head crosses the surgical field from medial to lateral and is retracted to expose the SN, which lies beneath it. Care must be taken to preserve the motor branches for the hamstring muscles, as well as the posterior femoral cutaneous nerve of the thigh. Fig. 6 shows the location of the SN and the relation with PMTA at the thigh region. Fig. 6 Posterior mid-thigh approach. Fig. 6 Posterior mid-thigh approach. Distally, at the level of the PF, the SN bifurcates into its terminal branches: the tibial and common peroneal nerves. The surgical approach must account for whether exposure is needed more toward the midline or lateral aspect of the PF, given the diverging trajectories of these two branches. The PF resembles a rhomboid-shaped anatomical space, bounded proximally and medially by the SM and ST muscles, proximally and laterally by the biceps femoris, and distally by the medial and lateral heads of the gastrocnemius muscle. The tibial nerve continues distally through the central portion of the PF lying superficial to the popliteal vessels as it proceeds toward the posterior compartment of the leg. In contrast, the common peroneal nerve turns laterally, passing beneath the biceps femoris muscle as it courses toward the lateral compartment of the leg. For optimal exposure and reduced risk of wound complications, the skin incision should be made obliquely across the PF ( Kline et al., 2001 ; Lee et al., 2022 ; Steinmetz et al., 2007 ; Siqueira and Martins, 2006 ). After the skin incision, the distal aponeurosis is incised and the intermuscular plane is carefully developed to expose the distal segment of the SN, while ensuring protection of the popliteal vessels. Fig. 7 shows the location of the SN and the relation with PFA at the popliteal region. Fig. 7 Popliteal fossa approach. Fig. 7 Fig. 8 Modified transgluteal approach with sciatic notch widening. Fig. 8 Popliteal fossa approach. Modified transgluteal approach with sciatic notch widening. Since the SN is the longest nerve in the human body, it maintains anatomical relationships with multiple muscular and vascular structures, as well as with two major joints, throughout its course along the four anatomical regions it traverses in the lower limb. The various surgical approaches and their variants described in the literature aim to provide the optimal surgical exposure while minimizing aesthetic and functional morbidity ( Kapandji, 2008 ). Currently, in Neurosurgery, minimally-invasive and endoscopic-assisted techniques, are increasingly employed to perform less disruptive surgical approaches and to enhance postoperative recovery ( Socolovsky and Masi, 2012 ; Socolovsky et al., 2011 ; Giuliano et al., 2015 ; Socolovsky, 2010 ; Hogan et al., 2020 ; Domb et al., 2025 ; Park et al., 2016a ; Jackson, 2016 ; Belyak et al., 2021 ; Martin et al., 2012 ). We believe that a comprehensive understanding of these approaches may also be of particular interest to peripheral nerve surgeons, given their potential to optimize exposure while reducing trauma and morbidity. In the upper third of the lower limb, the SN has a close anatomical relationship with the hip joint, which explains its high incidence of injury during hip arthroplasty and blunt trauma (13.8% in our series). Traction injury due to the use of surgical retractors is the most commonly reported mechanism, as described by several authors ( Nakamura et al., 2022 ; Stavrakakis et al., 2022 ; Sharp et al., 2021 ; Liu et al., 2022 ; Issack and Helfet, 2009 ; Yeremeyeva et al., 2009 ). Spontaneous recovery following blunt trauma has been reported in approximately 64.7% to 74.1% of cases. When surgical intervention is indicated —such as in the presence of persistent functional impairment or refractory neuropathic pain— external neurolysis appears to offer the best chance of a favorable outcome, with success rates ranging from 80% to 87% ( Park et al., 2016a ; Stavrakakis et al., 2022 ; Liu et al., 2022 ; Issack and Helfet, 2009 ; Yeremeyeva et al., 2009 ; Kim and Park, 2014 ; Kline and Hudson, 1995 ). Injection-related injuries, resulting from the improper administration of intramuscular injections, are a common yet under-reported complication in developing countries, particularly among children and elderly patients. The SN may be damaged by direct needle trauma, increased local pressure, or chemical irritation from the injected substance itself. Clinical presentation can range from acute to delayed-onset of transient or permanent pain and functional impairment ( Kline and Hudson, 1995 ; Park et al., 2019 ; Jung Kim and Hyun Park, 2014 ; Tak et al., 2008 ; Mansoor et al., 2005 ; Villarejo and Pascual, 1993 ). Literature reports highlight that chemical injection injuries may benefit from external neurolysis in a high percentage of cases; however, there is no consensus regarding the optimal timing for surgical intervention. Nevertheless, favorable outcomes have been documented with early surgery (within six months), showing success rates of up to 81.8% ( Jung Kim and Hyun Park, 2014 ; Topuz et al., 2011 ; Kumar et al., 2019 ). Ganglion cysts are rare lesions, typically associated with degenerative pathology of hip joint, that can compress the SN and lead to neuropathic pain, sensory disturbances and motor weakness. Progressive enlargement of the cyst may necessitate surgical excision and disconnection of the involved nerve branch from the cyst to relieve symptoms and reduce the risk of recurrence. In our series, we report two cases presenting with pain and paresthesia, one of which also exhibited drop foot ( Yang et al., 2013 ; Park et al., 2016b ; Masuda and Takahashi, 2023 ; Wu et al., 2011 ; Lakhotia et al., 2017 ). The surgical principles for accessing the subgluteal space (Stookey's approach) to expose the SN and its variants have remained largely unchanged. There is a consensus that this approach provides an excellent exposure of the SN, including oncological surgery. However, complete detachment of the GMM may lead to muscle atrophy, resulting in both cosmetic and functional disadvantages, as well as prolonged recovery time, given the GMM's critical role in standing and ambulation. For this reason, the TGA is preferred over the classic Stookey approach in recent years. Since it requires a less invasive incision and the GMM fibers are bluntly separated rather than transected, providing adequate SN exposure while achieving optimal aesthetic and functional outcomes ( Martínez et al., 2018 ; Socolovsky and Masi, 2012 ; Socolovsky et al., 2011 ; Socolovsky, 2010 ). In our experience, the TGA is safe and provides exposure of up to 10 cm of the SN in the gluteal region, while also allowing visualization of the pudendal nerve as it courses from the pelvis to the perineum. For more extensive exposures, additional windows can be created through the GMM (proximal or distal) to access the full length of the lesion. Therefore, this approach is versatile and can be applied in various clinical scenarios, including nerve decompression, microsurgical reconstruction, and benign tumor resection. However, it should be avoided in the treatment of malignant tumors, as these typically require extensive dissection, and cosmetic and muscle functional preservation become secondary considerations ( Fessler and Sekhar, 2006 ). In some cases, extensive exposure of the most proximal segment of the SN—proximal to the piriformis muscle— may require additional dissection or bone removal. A recently developed modification by one of the authors, designed for lesions with partial intrapelvic extension, involves enlargement of the sciatic notch to allow wide exposure of the proximal intrapelvic portion of the tumor (2 cases of our series). In this modification of Stookey's approach, described in 2018, the patient is positioned prone, and the surgical incision follows the lateral border of the sacral bone. This allows exposure of the medial margin of the GMM, which is sectioned and retracted laterally to reveal the medial aspect of the sciatic notch. A triangular sacral bone flap is then removed to provide direct access to the proximal segment of the SN. Fig. 8 ( Birch, 2010 ; Munakomi and Shrestha, 2017a ; Garozzo et al., 2018 ). In 1946, Seletz proposed using the lower (horizontal) segment of the Stookey's approach when only limited exposure near the gluteal fold is required. This modification involves severing only a small portion of the GMM, thereby avoiding the extensive dissection associated with the classic approach, which was considered excessive for more distal lesions ( Seletz, 1946b ). Additionally, the IGA facilitates a smooth transition to the proximal part of the SN at the thigh level. Based on our experience, this approach does not require sectioning of the inferior fibers of the GMM. In our series, we employed the IGA alone in 13 cases, in combination with the TGA in one case, and with the PMTA in another. Although its application and description in literature are limited, one suggested use of the IGA is in the management of hip and knee spasticity through selective neurotomies. A recent anatomical study demonstrated that the motor branches to the biceps femoris, ST, and SM muscles originate within a 15 cm-long segment of the SN at the level of the greater trochanter. These nerve branches can be reliably identified and accessed through the IGA ( Bretonnier et al., 2019 ; Decq et al., 1996 ). Our series includes one case in which this approach was successfully applied for the removal of a solitary Schwannoma. Fig. 5 In the context of traumatic injuries, with extensive involvement of the SN in the gluteal region, the IGA may be combined with the TGA in selective cases to achieve adequate exposure of the SN, extending from the greater sciatic notch to its distal segment at the gluteal-thigh transition. Although this strategy requires two incisions, cosmetic and functional outcomes are often superior to those achieved with the classic approach. As previously described in the literature, we concur that the mid-thigh surgical approach performed through a posterior midline incision, presents minimal anatomical disadvantages ( Garozzo et al., 2018 ; Aydin et al., 2010 ; Capek et al., 2015 ; Rigoard et al., 2009 ; Munakomi and Shrestha, 2017b ; Abou-Al-Shaar et al., 2018 ). The PF contains several important structures, including the popliteal artery, popliteal vein, and the SN with its terminal branches. These structures are arranged medially to laterally and deep to superficial, requiring particular caution when approaching the SN in cases of gunshot injuries. This is especially important due to the risk of vascular injury during dissection, as well as potential damage to the motor branches innervating the gastrocnemius, soleus, plantaris and popliteus muscles, which may be obscured by fibrosis. In addition, the cutaneous branches of the common peroneal nerve —such as the sural communicating branch and lateral cutaneous nerve of the calf— should be carefully preserved to prevent sensory deficits or neuropathic pain in posterolateral leg and lateral aspect of the foot ( Vloka et al., 2001 ; Tomaszewski et al., 2016 ; Thiery, 1986 ; Nichols and Ahford, 2013 ; Schiarite et al., 2015 ; Nair et al., 2000 ; Khanna et al., 2006 ; Turkman et al., 2023 ). Generally, incisions used for proximal approaches have low complication rate. However, when performing surgical approaches to the distal third of the thigh crossing the PF, it is important to consider oblique incisions or Z-plasty-type extensions along cutaneous tension lines relative to the long axis of the knee joint, in order to minimize postoperative wound complications. The intrapelvic segment of the SN corresponds to the portion located within the pelvis before exiting through the greater sciatic foramen. Fig. 9 . Fig. 9 Intrapelvic portion of the sciatic nerve (anterior view). Fig. 9 Intrapelvic portion of the sciatic nerve (anterior view). Surgical access to this region is complex due to its deep location and the close relationship with multiple neurovascular, gastrointestinal, and genitourinary structures surrounding the SN. Pathologies such as tumors, gynecological conditions (e.g., fibroids, endometriosis, etc.), vascular abnormalities, or trauma may produce sciatica by compressing or irritating the nerve roots or the nerve itself ( Kale et al., 2021 ). Management depends on the underlying etiology. Nevertheless, surgical indications involving this intrapelvic segment are relatively uncommon and may require laparoscopic approaches—frequently associated with gynecological surgery— ( Lemos and Possover, 2015 ; Grigoriadis et al., 2025 ) or open transabdominal approaches, used alone or in combination with a buttock extrapelvic route, particularly for the management sciatic-notch dumbbell-shaped tumors in selected cases after thorough high-resolution MRI evaluation ( Montano et al., 2013 ; Consales et al., 2006 ; Spinner et al., 2006 ). No extensive intrapelvic lesions requiring an intrapelvic approach were identified in our series. This study reinforces the importance of tailoring the surgical approach to the anatomical level and etiology of the SN pathology.

The sciatic nerve (SN) is the largest and longest nerve in the human body. It is formed within the pelvis by the union of the lumbosacral trunk and the S1 to S3 roots. From there, it exits the pelvis through the infrapiriform portion of the greater sciatic foramen to enter the gluteal region, and then descends along the midline of the posterior thigh, deep to the hamstring muscles. At the apex of the popliteal fossa (PF), in the distal third of the thigh, it bifurcates into two terminal branches: the tibial (medial) and common peroneal (lateral) nerves. These divisions are already anatomically distinct within the sciatic nerve from their origin in the pelvis, separated by the Compton-Cruveilhier septum, and enclosed within a common epi-perineural sheath. Along its proximal course, the SN gives off motor branches to the following muscles: the semimembranosus (SM) , semitendinosus (ST) , adductor magnus , the long head of the biceps femoris (tibial division), and the short head of the biceps femoris (peroneal division). The muscles of the leg and foot are innervated by its terminal branches: the tibial nerve, which supplies the posterior compartment, and the common peroneal nerve, which innervates the anterolateral compartment ( Giuffre et al., 2025 ; Dupont et al., 2018 ; Rabh, 1948 ; Martínez et al., 2013 ). Surgical exposure of the SN is required in several clinical scenarios, including traumatic injuries, entrapment syndromes, and nerve tumors. Many surgical approaches have been developed based on the distinct anatomical relationships of the SN as it courses through the pelvic, gluteal, thigh, and popliteal regions ( Kozioł et al., 2024 ; Atoni et al., 2022 ; Martínez et al., 2018 ). Fig. 1 , Fig. 2 depict the anatomical location of the SN and its main anatomical relationships with surgical landmarks. Fig. 1 Anatomical course of the sciatic nerve. Fig. 1 Fig. 2 Cadaveric dissection of the sciatic nerve: A) gluteal region, B) thigh, and C) popliteal fossa. Fig. 2 Anatomical course of the sciatic nerve. Cadaveric dissection of the sciatic nerve: A) gluteal region, B) thigh, and C) popliteal fossa. This study aims to evaluate the feasibility of various surgical approaches according to the location and type of sciatic nerve injuries, based on descriptive data from a multicenter case series and supported by a comprehensive literature review.

Sciatic nerve Popliteal fossa Semimembranosus Semitendinosus Transgluteal approach Infragluteal approach Posterior mid-thigh approach Popliteal fossa approach Gluteus maximus muscle

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.