{"id":8113,"date":"2026-02-05T10:25:11","date_gmt":"2026-02-05T09:25:11","guid":{"rendered":"https:\/\/blueportance.com\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/mechanical-locks\/"},"modified":"2026-10-25T22:43:40","modified_gmt":"2026-10-25T21:43:40","slug":"mechanical-locks","status":"publish","type":"page","link":"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/mechanical-locks\/","title":{"rendered":"KB_Pudendal Neuralgia_02 : Mechanical Vulnerability and Pudendal Nerve Entrapment Mechanisms"},"content":{"rendered":"\n\n\n<style>\n  .bp-bdc-wrap {\n    max-width: 980px;\n    margin: 0 auto;\n    padding: 0 16px 48px;\n    color: #222;\n    line-height: 1.65;\n  }\n\n  .bp-bdc-breadcrumb {\n    max-width: 900px;\n    margin: 0 auto;\n    padding: 20px 16px 0;\n    font-size: .85rem;\n    color: #6b7280;\n  }\n\n  .bp-bdc-breadcrumb a {\n    color: #2a7fba;\n    text-decoration: none;\n  }\n\n  .bp-bdc-breadcrumb a:hover {\n    text-decoration: underline;\n  }\n\n  .bp-bdc-hero {\n    max-width: 900px;\n    margin: 30px auto 0;\n  }\n\n  .bp-bdc-hero h1 {\n    margin-bottom: 18px;\n    line-height: 1.2;\n  }\n\n  .bp-bdc-meta {\n    margin-top: 22px;\n    padding: 12px 16px;\n    background: #f4f8fb;\n    border-left: 4px solid #2a7fba;\n    color: #52606d;\n    font-size: .9rem;\n  }\n\n  .bp-bdc-toc {\n    max-width: 900px;\n    margin: 34px auto;\n    padding: 22px 26px;\n    background: #f7fafc;\n    border: 1px solid #e1e8ee;\n    border-radius: 10px;\n  }\n\n  .bp-bdc-toc h2 {\n    margin-top: 0;\n  }\n\n  .bp-bdc-toc a {\n    color: #1e73be;\n  }\n\n  .bp-bdc-content {\n    max-width: 900px;\n    margin: 0 auto;\n  }\n\n  .bp-bdc-content h2 {\n    margin-top: 48px;\n    padding-bottom: 8px;\n    border-bottom: 2px solid #d9e8f5;\n    line-height: 1.3;\n  }\n\n  .bp-bdc-content h3 {\n    margin-top: 32px;\n    line-height: 1.35;\n  }\n\n  .bp-bdc-content p {\n    margin: 0 0 18px;\n  }\n\n  .bp-bdc-content ul,\n  .bp-bdc-content ol {\n    margin-bottom: 22px;\n  }\n\n  .bp-bdc-content li {\n    margin-bottom: 10px;\n  }\n\n  .bp-bdc-box {\n    margin: 26px 0;\n    padding: 20px 24px;\n    border-radius: 10px;\n  }\n\n  .bp-bdc-box--soft {\n    background: #f4f8fb;\n    border: 1px solid #d9e8f5;\n  }\n\n  .bp-bdc-box--warning {\n    background: #fff8ed;\n    border-left: 4px solid #f39c12;\n  }\n\n  .bp-figure {\n    margin: 30px auto;\n    padding: 0;\n    text-align: center;\n  }\n\n  .bp-figure img {\n    display: block;\n    width: 100%;\n    max-width: 900px;\n    height: auto;\n    margin: 0 auto;\n  }\n\n  .bp-figure figcaption {\n    margin-top: 12px;\n    color: #59636e;\n    font-size: .92rem;\n    text-align: left;\n  }\n\n  .bp-bdc-navigation {\n    margin-top: 44px;\n    padding: 22px 24px;\n    background: #f7fafc;\n    border: 1px solid #e1e8ee;\n    border-radius: 10px;\n  }\n\n  .bp-bdc-navigation a {\n    color: #1e73be;\n  }\n\n  .bp-bdc-footer {\n    margin-top: 28px;\n    padding: 18px 20px;\n    background: #fff8ed;\n    border-left: 4px solid #f39c12;\n    font-size: .92rem;\n  }\n\n  .bp-bdc-copyright {\n    font-size: .85em;\n    color: #6b7280;\n    margin-top: 22px;\n  }\n\n  .bp-reference-note {\n    color: #59636e;\n    font-size: .9rem;\n  }\n\n  .bp-bdc-level {\n    display: inline-block;\n    margin: 0 6px 6px 0;\n    padding: 3px 8px;\n    border-radius: 999px;\n    background: #eaf3f9;\n    color: #245f85;\n    font-size: .78rem;\n    font-weight: 700;\n    letter-spacing: .02em;\n  }\n\n  @media (max-width: 700px) {\n    .bp-bdc-wrap {\n      padding-left: 12px;\n      padding-right: 12px;\n    }\n\n    .bp-bdc-box {\n      padding: 18px;\n    }\n  }\n<\/style>\n\n<nav class=\"bp-bdc-breadcrumb\" aria-label=\"Breadcrumb\">\n<a href=\"\/en\/\">Blue Portance<\/a> \u2192 <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/\">Knowledge Base<\/a> \u2192 <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/\">Sitting-Related Pain<\/a> \u2192 <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/\">Pudendal Neuralgia<\/a> \u2192 Mechanical Vulnerability\n<\/nav>\n\n<section class=\"bp-bdc-wrap\">\n\n  <header class=\"bp-bdc-hero\">\n\n    <h1>\n      Mechanical Vulnerability and Pudendal Nerve Entrapment Mechanisms\n    <\/h1>\n\n    <p>\n      The pudendal nerve follows a complex course through the pelvis, in contact\n      with several ligamentous, muscular, vascular, and fascial structures.\n      Certain regions along this course have been described as potentially\n      vulnerable anatomical zones, particularly around the ischial spine and\n      within Alcock&#8217;s canal (pudendal canal).\n    <\/p>\n\n    <p>\n      The presence of an anatomically narrow zone does not, however, mean that\n      pathological compression is present in every patient. The clinical\n      relevance of a possible entrapment must be assessed by taking into account the\n      pain distribution, the symptom pattern, the clinical examination,\n      and the available additional diagnostic testing\n      (Robert et al., 1998; Labat et al., 2008;\n      Zapletal et al., 2024).\n    <\/p>\n\n    <p>\n      This page distinguishes three levels: established anatomical\n      relationships, the plausible mechanical consequences of those\n      relationships, and their integration into the SBNFA\u2122 functional model.\n      Within this framework, a \u201cmechanical lock\u201d (SBNFA\u2122 term) does not automatically denote\n      a lesion: it describes a zone whose adaptive capacity may become\n      insufficient under certain conditions of load, posture, or recovery.\n    <\/p>\n\n    <div class=\"bp-bdc-meta\">\n      Blue Portance Knowledge Base \u00b7 Non-commercial reproduction\n      permitted with citation of the source\n    <\/div>\n\n  <\/header>\n\n  <nav class=\"bp-bdc-toc\" aria-label=\"Table of contents\">\n\n    <h2>Table of Contents<\/h2>\n\n    <ul>\n      <li>\n        <a href=\"#principe\">\n          1. Understanding the concept of a zone of mechanical vulnerability\n        <\/a>\n      <\/li>\n\n      <li>\n        <a href=\"#pince\">\n          2. The ischial spine region and ligamentous relationships\n        <\/a>\n      <\/li>\n\n      <li>\n        <a href=\"#canal\">\n          3. Alcock&#8217;s canal: fascial pathway and potential zone of mechanical interference\n        <\/a>\n      <\/li>\n\n      <li>\n        <a href=\"#cumul\">\n          4. Cumulative stress and symptom variability\n        <\/a>\n      <\/li>\n\n      <li>\n        <a href=\"#references\">\n          Scientific references\n        <\/a>\n      <\/li>\n    <\/ul>\n\n  <\/nav>\n\n  <article class=\"bp-bdc-content\">\n\n    <section id=\"principe\">\n\n      <h2>\n        1. Understanding the concept of a zone of mechanical vulnerability\n      <\/h2>\n\n      <p>\n        <span class=\"bp-bdc-level\">ESTABLISHED DATA<\/span>\n        <span class=\"bp-bdc-level\">MECHANICAL INTERPRETATION<\/span>\n        <span class=\"bp-bdc-level\">SBNFA\u2122 FRAMEWORK<\/span>\n      <\/p>\n\n      <p>\n        The course of the pudendal nerve involves several changes of direction\n        and several close relationships with pelvic structures. The main points\n        of anatomical interest include the ischial spine region, the\n        sacrospinous and sacrotuberous ligaments, the falciform process, and\n        Alcock&#8217;s canal (pudendal canal)\n        (Robert et al., 1998; Zapletal et al., 2024).\n      <\/p>\n\n      <p>\n        To review the full course and the branches involved, see\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/pudendal-nerve-anatomy\/\">\n          Functional Anatomy and Neuromechanics of the Pudendal Nerve\n        <\/a>.\n      <\/p>\n\n      <p>\n        On this page, the expression <strong>zone of mechanical vulnerability<\/strong>\n        is preferred to \u201clock\u201d when there is no evidence of pathological\n        compression. It refers to a region in which anatomical relationships may\n        make the nerve sensitive to certain stresses, without presupposing the\n        mechanism at work in any given patient.\n      <\/p>\n\n      <p>\n        The term <strong>mechanical lock<\/strong> is reserved for the SBNFA\u2122\n        functional interpretation: a zone of vulnerability becomes a lock when\n        the local capacity for gliding, strain, redistribution, or recovery is\n        no longer sufficient to absorb the loads placed on it. The lock therefore\n        describes a <strong>temporarily unfavorable relationship between a\n        geometry, a load, and an adaptive capacity<\/strong>; it is neither\n        synonymous with a fixed lesion nor equivalent to a demonstrated compression.\n      <\/p>\n\n      <p>\n        Anatomical mechanical interference may involve compression, traction, shear, or\n        local irritation. These mechanisms may be intermittent or permanent, but\n        their existence cannot be inferred from the location of the pain\n        alone.\n      <\/p>\n\n      <p>\n        Posture dependence is an important clinical feature.\n        Worsening in the seated position is one of the essential Nantes\n        criteria, but it cannot be used to locate the precise site of\n        involvement with certainty, nor to demonstrate ligamentous compression\n        (Labat et al., 2008).\n      <\/p>\n\n      <div class=\"bp-bdc-box bp-bdc-box--soft\">\n\n        <strong>Key point<\/strong>\n\n        <p>\n          <strong>Zone of vulnerability<\/strong> = a potentially sensitive\n          anatomical configuration. <strong>Mechanical lock<\/strong> = a\n          functional state in which local adaptive capacities become\n          insufficient in the face of stress. <strong>Entrapment or compression<\/strong>\n          = a clinical mechanism that must be demonstrated, and not an automatic\n          consequence of the two preceding notions.\n        <\/p>\n\n      <\/div>\n\n    <\/section>\n\n    <section id=\"pince\">\n\n      <h2>\n        2. The ischial spine region and ligamentous relationships\n      <\/h2>\n\n      <p>\n        <span class=\"bp-bdc-level\">ESTABLISHED ANATOMY<\/span>\n        <span class=\"bp-bdc-level\">BIOMECHANICAL HYPOTHESIS<\/span>\n      <\/p>\n\n      <p>\n        The pudendal nerve passes close to the ischial spine and the\n        sacrospinous and sacrotuberous ligaments. This region is an important\n        anatomical zone in descriptions of pudendal nerve entrapment\n        (Robert et al., 1998).\n      <\/p>\n\n      <p>\n        In some situations, the relationships between the nerve, the ligaments,\n        and the neighboring tissues may contribute to local irritation. The term\n        <strong>ligamentous clamp<\/strong>, formed by the sacrotuberous and\n        sacrospinous ligaments, may be used as a descriptive anatomical model\n        (Shafik et al., 2007), but it should not be presented as an\n        automatic diagnosis or as a mechanism demonstrated in all\n        people suffering from pudendal pain.\n      <\/p>\n\n      <p>\n        In the clinical literature, the ligamentous clamp refers to the space\n        where the pudendal nerve, after passing around the ischial spine and\n        through the lesser sciatic foramen, runs between the sacrotuberous\n        ligament, below, and the sacrospinous ligament, above, accompanied by\n        the pudendal artery and veins. Ziouziou et al. (2013) describe this\n        region as a frequent site of nerve irritation.\n      <\/p>\n\n      <p>\n        Sitting may aggravate symptoms in some patients.\n        This aggravation may reflect the interaction of several factors:\n        local pressure, pelvic orientation, duration of exposure, muscle\n        tension, nerve sensitivity, and individual recovery capacity.\n        It has not been established that posterior pelvic tilt\n        systematically increases ligament tension or reduces the space available\n        for the nerve in all individuals.\n      <\/p>\n\n      <p>\n        From a mechanical standpoint, a change in pelvic orientation or in the\n        tension transmitted by neighboring tissues may nonetheless alter the\n        relative geometry of this region and the way stresses are distributed\n        within it. This proposition is consistent with anatomy, but its\n        magnitude, direction, and clinical significance vary from person to person;\n        it therefore does not justify establishing a single posture, notably\n        posterior pelvic tilt, as a universal cause.\n      <\/p>\n\n      <p>\n        The ligamentous model should therefore be formulated as a biomechanical\n        hypothesis that may explain certain clinical pictures, and not as\n        universal causation.\n      <\/p>\n\n      <figure class=\"bp-figure\">\n\n        <img decoding=\"async\"\n          src=\"https:\/\/blueportance.com\/wp-content\/uploads\/IMG_NP_Ligamentous-clamp.jpg\"\n          alt=\"Relationships of the pudendal nerve with the sacrospinous and sacrotuberous ligaments near the ischial spine\"\n          loading=\"lazy\">\n\n        <figcaption>\n          <strong>\n            Ischial spine region and ligamentous relationships.\n          <\/strong>\n          The pudendal nerve runs close to the sacrospinous and\n          sacrotuberous ligaments. This anatomical relationship may be relevant in\n          certain forms of entrapment, but the image alone does not allow one to\n          conclude that pathological compression is present in a given patient\n          (Robert et al., 1998; Zapletal et al., 2024).\n        <\/figcaption>\n\n      <\/figure>\n\n      <p>\n        Worsening in the seated position remains an important clinical feature\n        in the assessment of pudendal neuralgia. It is one of the Nantes\n        criteria, along with pain located in the pudendal territory, the usual\n        absence of nocturnal awakening, the absence of objective sensory deficit, and\n        improvement after an anesthetic pudendal nerve block\n        (Labat et al., 2008).\n      <\/p>\n\n    <\/section>\n\n    <section id=\"canal\">\n\n      <h2>\n        3. Alcock&#8217;s canal: fascial pathway and potential zone of mechanical interference\n      <\/h2>\n\n      <p>\n        <span class=\"bp-bdc-level\">ESTABLISHED ANATOMY<\/span>\n        <span class=\"bp-bdc-level\">MECHANICAL INTERFACE<\/span>\n      <\/p>\n\n      <p>\n        After passing near the ischial spine, the pudendal nerve runs\n        through the pudendal canal, also known as Alcock&#8217;s canal. This canal\n        corresponds to a splitting of the fascia associated with the obturator\n        internus muscle and contains the pudendal neurovascular bundle\n        (Robert et al., 1998; Zapletal et al., 2024).\n      <\/p>\n\n      <p>\n        According to Ziouziou et al. (2013), the nerve may also be involved\n        slightly more distally, in Alcock\u2019s canal, located about 15 mm further\n        along and about 16 mm long. At this level, the fat surrounding the\n        neurovascular bundle gives way to fibrous tissue. The authors describe\n        venous stasis that may promote an entrapment syndrome in the seated\n        position, particularly when the canal is narrowed or compressed by the\n        falciform process of the sacrotuberous ligament. These elements describe\n        a possible mechanism, not a systematic course.\n      <\/p>\n\n      <p>\n        Alcock&#8217;s canal can be described as a constrained anatomical\n        interface. It is not necessarily a pathological tunnel,\n        but a space in which the relationships between the nerve, the vessels,\n        the fascia, and the muscular structures may become clinically\n        relevant in certain situations.\n      <\/p>\n\n      <p>\n        Anatomical variations, a scar, a local change in the\n        tissues, or mechanical stress could theoretically influence this\n        environment. However, the available data do not support\n        the assertion that pelvic floor hypertonia systematically reduces\n        the volume of the canal or causes compression of the nerve.\n      <\/p>\n\n      <p>\n        It is also useful to distinguish two levels of analysis. The first\n        is anatomical: it concerns the presence of an abnormality or of a\n        structural relationship that could cause mechanical interference. The second is functional: it\n        concerns the nerve&#8217;s tolerance to variations in pressure, tension, and\n        movement.\n      <\/p>\n\n      <p>\n        This functional tolerance presupposes relative mobility between the nerve,\n        its sheaths, the vessels, and the obturator internus fascia. Alcock&#8217;s\n        canal should therefore not be represented as a rigid conduit: it is\n        a living tissue interface, bound to the neighboring structures yet\n        capable, under physiological conditions, of accompanying their relative\n        movements.\n      <\/p>\n\n      <p>\n        In the SBNFA\u2122 interpretation, the lock does not necessarily correspond to a\n        permanent reduction in the caliber of the canal. It may also refer to a\n        situation in which repeated or concentrated stress loads\n        this interface faster than it can redistribute or recover from it.\n        This mechanism makes an intermittent expression, dependent on\n        the duration of exposure, conceivable, without demonstrating that it explains the individual case.\n      <\/p>\n\n      <figure class=\"bp-figure\">\n\n        <img decoding=\"async\"\n          src=\"https:\/\/blueportance.com\/wp-content\/uploads\/IMG_NP_Alcoks-canal.jpg\"\n          alt=\"Alcock's canal and the course of the pudendal nerve within the obturator internus fascia\"\n          loading=\"lazy\">\n\n        <figcaption>\n          <strong>\n            Alcock&#8217;s canal and the course of the pudendal nerve.\n          <\/strong>\n          The pudendal canal forms a fascial pathway for the pudendal nerve. This\n          configuration may represent a zone of vulnerability in certain\n          anatomical or clinical contexts, without on its own demonstrating\n          pathological compression or a loss of gliding\n          (Robert et al., 1998; Zapletal et al., 2024).\n        <\/figcaption>\n\n      <\/figure>\n\n      <p>\n        The fascial densification model may be invoked as a general\n        hypothesis regarding possible changes in connective tissue\n        interfaces. It should not, however, be presented as specific\n        evidence of densification of Alcock&#8217;s canal in pudendal\n        neuralgia\n        (Pavan et al., 2014; Stecco et al., 2019).\n      <\/p>\n\n      <p>\n        The dynamics of this interface are developed in\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/fascia-neural-gliding\/\">\n          Fascia, Nerve Gliding, and Tissue Densification\n        <\/a>.\n      <\/p>\n\n    <\/section>\n\n    <section id=\"cumul\">\n\n      <h2>\n        4. Cumulative stress and symptom variability\n      <\/h2>\n\n      <p>\n        <span class=\"bp-bdc-level\">MULTIFACTORIAL MODEL<\/span>\n        <span class=\"bp-bdc-level\">SBNFA\u2122 HYPOTHESIS<\/span>\n      <\/p>\n\n      <p>\n        Anatomical factors should not be analyzed in isolation. A potentially\n        vulnerable zone may be better tolerated in one person and\n        less well tolerated in another, depending on nerve sensitivity,\n        medical history, exposure to stress, recovery, and\n        neuromuscular factors.\n      <\/p>\n\n      <p>\n        A clinical picture may therefore result from the interaction between an\n        anatomical predisposition, repeated mechanical load, muscle\n        tension, sensitization of the nervous system, and insufficient\n        recovery. This formulation describes a multifactorial model and does not\n        mean that several anatomical compressions are necessarily\n        present.\n      <\/p>\n\n      <p>\n        Within SBNFA\u2122, the \u201caccumulation of locks\u201d thus refers not to an\n        automatic addition of lesions, but to the progressive reduction of\n        compensatory possibilities. A first zone may remain silent\n        as long as other segments or interfaces absorb and redistribute the\n        load. When several possibilities for adjustment become limited,\n        the same load may become more concentrated on the nerve pathway\n        and be less well tolerated.\n      <\/p>\n\n      <p>\n        This interpretation connects four dimensions: <strong>geometry of the passages<\/strong>,\n        <strong>relative mobility of the tissues<\/strong>, <strong>variability of\n        stress<\/strong>, and <strong>recovery<\/strong>. It explains why\n        sitting duration, repetition, the inability to vary support points, and the\n        neuromuscular context can matter as much as the instantaneous intensity\n        of a pressure.\n      <\/p>\n\n      <p>\n        Symptom variability \u2014 periods of remission, flare-ups in the\n        seated position, the influence of exposure duration, and improvement with\n        changes of position \u2014 may be compatible with an intermittent\n        mechanical mechanism. It may also reflect factors of\n        nerve sensitivity or pain modulation.\n      <\/p>\n\n      <p>\n        The Nantes criteria can help structure the clinical assessment,\n        but they cannot determine the number of anatomical zones\n        involved, nor distinguish with certainty between compression, irritation,\n        sensitization, or a mixed mechanism\n        (Labat et al., 2008).\n      <\/p>\n\n      <div class=\"bp-bdc-box bp-bdc-box--soft\">\n\n        <strong>Key takeaway<\/strong>\n\n        <p>\n          The mechanical lock is a functional concept: it describes a local loss\n          of adaptive possibilities, not necessarily an anatomical\n          obstruction. In pudendal neuralgia, anatomical,\n          mechanical, neuromuscular, and neurophysiological factors may interact,\n          but their contribution must be assessed individually.\n        <\/p>\n\n      <\/div>\n\n    <\/section>\n\n    <section id=\"references\">\n\n      <h2>Scientific references<\/h2>\n\n      <div class=\"bp-bdc-box bp-bdc-box--soft\">\n\n        <ol>\n\n          <li>\n            <strong>\n              Robert R, Prat-Pradal D, Labat JJ, Bensignor M, Raoul S, Rebai R,\n              Leborgne J.\n            <\/strong>\n            Anatomic basis of chronic perineal pain: role of the pudendal nerve.\n            <em>Surgical and Radiologic Anatomy<\/em>.\n            1998;20(2):93\u201398.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.1007\/BF01628908\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.1007\/BF01628908\n            <\/a>.\n            <br>\n            <a\n              href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/9658526\/\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              View PubMed record\n            <\/a>\n          <\/li>\n\n          <li>\n            <strong>\n              Labat JJ, Riant T, Robert R, Amarenco G, Lefaucheur JP, Rigaud J.\n            <\/strong>\n            Diagnostic criteria for pudendal neuralgia by pudendal nerve entrapment\n            (Nantes criteria).\n            <em>Neurourology and Urodynamics<\/em>.\n            2008;27(4):306\u2013310.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.1002\/nau.20505\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.1002\/nau.20505\n            <\/a>.\n            <br>\n            <a\n              href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/17828787\/\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              View PubMed record\n            <\/a>\n          <\/li>\n\n          <li>\n            <strong>\n              Zapletal J, Nanka O, Halaska MJ, Maxova K, Hajkova Hympanova L,\n              Krofta L, et al.\n            <\/strong>\n            Anatomy of the pudendal nerve in clinically important areas:\n            a pictorial essay and narrative review.\n            <em>Surgical and Radiologic Anatomy<\/em>.\n            2024;46(2):211\u2013222.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.1007\/s00276-023-03285-7\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.1007\/s00276-023-03285-7\n            <\/a>.\n            <br>\n            <a\n              href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/38240796\/\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              View PubMed record\n            <\/a>\n          <\/li>\n\n          <li>\n            <strong>\n              Pavan PG, Stecco A, Stern R, Stecco C.\n            <\/strong>\n            Painful connections: densification versus fibrosis of fascia.\n            <em>Current Pain and Headache Reports<\/em>.\n            2014;18(8):441.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.1007\/s11916-014-0441-4\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.1007\/s11916-014-0441-4\n            <\/a>.\n          <\/li>\n\n          <li>\n            <strong>\n              Stecco A, Pirri C, Stecco C.\n            <\/strong>\n            Fascial entrapment neuropathy.\n            <em>Clinical Anatomy<\/em>.\n            2019;32(7):883\u2013890.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.1002\/ca.23388\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.1002\/ca.23388\n            <\/a>.\n          <\/li>\n\n          <li>\n            <strong>\n              Shafik A, El Sibai O, Shafik IA.\n            <\/strong>\n            Role of sacral ligament clamp in the pudendal neuropathy (pudendal canal\n            syndrome): results of clamp release.\n            <em>International Surgery<\/em>.\n            2007;92(1):54\u201359.\n            <br>\n            <a\n              href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/17390916\/\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              View PubMed record\n            <\/a>\n          <\/li>\n          <li>\n            <strong>\n              Ziouziou I, Bennani H, Zizi M, Karmouni T, El Khader K, Koutani A,\n              Iben Attya Andaloussi A.\n            <\/strong>\n            Le syndrome du canal d\u2019Alcock ou n\u00e9vralgie pudendale : un diagnostic\n            \u00e0 ne pas m\u00e9conna\u00eetre [Alcock\u2019s canal syndrome or pudendal neuralgia:\n            a diagnosis not to be overlooked].\n            <em>Canadian Urological Association Journal<\/em>.\n            2013;7(7-8):E486\u2013E489.\n            DOI:\n            <a\n              href=\"https:\/\/doi.org\/10.5489\/cuaj.415\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              10.5489\/cuaj.415\n            <\/a>.\n            <br>\n            <a\n              href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/23914265\/\"\n              target=\"_blank\"\n              rel=\"noopener\">\n              View PubMed record\n            <\/a>\n          <\/li>\n\n        <\/ol>\n\n        <p class=\"bp-reference-note\">\n          The anatomical and clinical references above do not demonstrate\n          that a \u201cmechanical lock,\u201d dynamic compression, or fascial\n          densification explains every case of pudendal pain. They\n          help distinguish established anatomical relationships from the proposed\n          functional or biomechanical models.\n        <\/p>\n\n      <\/div>\n\n      <div class=\"bp-bdc-box bp-bdc-box--warning\">\n\n        <strong>Blue Portance internal reference<\/strong>\n\n        <p>\n          The term \u201cmechanical lock,\u201d along with its integration into the\n          SBNFA\u2122 framework, constitutes a functional interpretive framework developed by\n          Blue Portance. It does not correspond to a validated medical\n          classification or to a stand-alone anatomical diagnosis.\n        <\/p>\n\n        <p>\n          Proposed internal reference:\n        <\/p>\n\n        <ul>\n          <li>\n            Blue Portance. SBNFA\u2122 Framework \u2014\n            <em>\n              Neuro-anatomie, partie II :\n              verrous m\u00e9caniques et contraintes pudendales\n            <\/em>\n            [Neuroanatomy, Part II: Mechanical Locks and Pudendal Stresses].\n            2026.\n          <\/li>\n        <\/ul>\n\n      <\/div>\n\n    <\/section>\n\n    <div class=\"bp-bdc-navigation\">\n      <strong>Pudendal Neuralgia Pathway<\/strong>\n      <p>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/pudendal-nerve-anatomy\/\">1. Functional Anatomy and Neuromechanics of the Pudendal Nerve<\/a><br>\n        <strong>2. Mechanical Vulnerability and Pudendal Nerve Entrapment Mechanisms<\/strong><br>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/referred-pain-trident\/\">3. Referred Pain and the Pudendal Trident: Understanding Symptom Territories<\/a><br>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/structural-functional-triage\/\">4. SBNFA\u2122 Triage: Distinguishing Structural Factors from Functional Mechanisms<\/a><br>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/fascia-neural-gliding\/\">5. Fascia, Nerve Gliding, and Tissue Densification<\/a><br>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/wandering-central-sensitization\/\">6. The Diagnostic Odyssey and Central Sensitization in Pudendal Neuralgia<\/a>\n      <\/p>\n      <p>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/pudendal-nerve-anatomy\/\">\u2190 Previous article<\/a> \u00b7\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/referred-pain-trident\/\">Next article \u2192<\/a>\n      <\/p>\n    <\/div>\n\n    <div class=\"bp-bdc-navigation\">\n\n      <strong>Navigation<\/strong>\n\n      <p>\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/pudendal-neuralgia\/\">\n          \u2190 Back to the Pudendal Neuralgia hub\n        <\/a>\n        <br>\n\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/sitting-related-pain\/\">\n          \u2190 See the topic: Sitting-Related Pain\n        <\/a>\n        <br>\n\n        <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/\">\n          \u2190 Explore the Knowledge Base\n        <\/a>\n      <\/p>\n\n    <\/div>\n\n    <footer class=\"bp-bdc-footer\">\n\n      <strong>Note:<\/strong>\n      this content aims to present anatomical, clinical, and\n      biomechanical information about the pudendal nerve. It constitutes neither a\n      medical diagnosis, nor a therapeutic recommendation, nor proof that\n      compression or fascial densification is present in a given\n      patient.\n\n    <\/footer>\n\n    <p class=\"bp-bdc-copyright\">\n      \u00a9 Gil Ayache. The concepts, diagrams, terminology, and principles presented on this page constitute a work protected by copyright. They are made available to Blue Portance under an intellectual property license agreement, without transfer of economic rights or of authorship.\n    <\/p>\n\n  <\/article>\n\n<\/section>\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>Blue Portance \u2192 Knowledge Base \u2192 Sitting-Related Pain \u2192 Pudendal Neuralgia \u2192 Mechanical Vulnerability Mechanical Vulnerability and Pudendal Nerve Entrapment Mechanisms The pudendal nerve follows a complex course through the pelvis, in contact with several ligamentous, muscular, vascular, and fascial structures. Certain regions along this course have been described as potentially vulnerable anatomical zones, particularly [&#8230;]\n","protected":false},"author":6,"featured_media":0,"parent":8099,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_yoast_wpseo_title":"Pudendal Nerve Entrapment and Vulnerability | Blue Portance","_yoast_wpseo_metadesc":"Where the pudendal nerve may be entrapped: ischial spine, ligamentous clamp, Alcock\u2019s canal \u2013 anatomy vs SBNFA\u2122 hypotheses.","footnotes":""},"pathologie_secondaire":[],"effet_positif":[],"class_list":["post-8113","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.7 (Yoast SEO v28.7) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>Pudendal Nerve Entrapment and Vulnerability | Blue Portance<\/title>\n<meta name=\"description\" content=\"Where the pudendal nerve may be 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