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Saddle anesthesia

Saddle anesthesia is a neurological symptom characterized by loss of sensation in the "saddle" region of the body, which includes the perianal area, buttocks, inner thighs, genitals, and sometimes the medial calves and posterior thighs, due to damage or compression of the sacral nerve roots (primarily S2-S4) or the conus medullaris of the spinal cord.^[1]^[2] This sensory deficit typically presents as numbness, tingling, or altered perception to touch, pain, temperature, and vibration in the affected areas, and it is most commonly associated with cauda equina syndrome (CES), a serious condition involving compression of the bundle of nerve roots at the lower end of the spinal cord.^[3]^[4] The primary causes of saddle anesthesia stem from pathologies that impinge on the cauda equina or conus medullaris, with the most frequent being a herniated lumbar disc, accounting for approximately 45% of CES cases.^[3] Other etiologies include spinal tumors, epidural abscesses, hematomas, trauma, spinal stenosis, infections, and iatrogenic factors such as post-surgical complications or anesthesia-related nerve injury.^[4]^[1] In CES, saddle anesthesia occurs in up to 93% of patients and often accompanies other red-flag symptoms, including severe low back pain, bilateral lower extremity weakness, bladder and bowel dysfunction (such as urinary retention or incontinence), and sexual dysfunction.^[3]^[2] As a critical indicator of potential irreversible neurological damage, saddle anesthesia demands urgent evaluation, typically involving MRI or CT imaging to identify the underlying compression, followed by prompt neurosurgical intervention like decompression if indicated.^[1]^[4] Delayed treatment beyond 48 hours can lead to permanent deficits in bladder, bowel, and lower limb function, underscoring its status as a surgical emergency.^[3] While less commonly linked to conus medullaris syndrome—which may present with more symmetric upper motor neuron signs like spasticity—saddle anesthesia remains a unifying feature of these lumbosacral disorders, highlighting the need for rapid multidisciplinary management.^[3]

Definition and Anatomy

Definition

Saddle anesthesia refers to a loss of sensation or numbness in the "saddle" distribution area of the body, encompassing the perineum, anus, genitals, inner aspects of the thighs, and buttocks.^[5]^[6] This sensory deficit specifically affects the regions that would make contact with a saddle during horseback riding, highlighting its characteristic perineal and sacral involvement.^[7] The condition arises from involvement of the dermatomes primarily supplied by the S2-S5 sacral nerve roots, leading to impaired perception of touch, pain, and temperature in these areas.^[8]^[3] As a symptom rather than a distinct disease entity, saddle anesthesia often presents asymmetrically, particularly in compressive neuropathies affecting the lower spinal nerve roots.^[5] Clinically, saddle anesthesia serves as a critical red-flag indicator of potential severe neurological compression, demanding urgent evaluation to prevent irreversible damage.^[1]^[7] It is frequently associated with cauda equina syndrome, where prompt intervention is essential.^[3]

Anatomical Basis

The saddle region refers to the perineal and perianal area that would contact a saddle, encompassing the inner aspects of the buttocks, the posterior thighs, the perineum, and the genitals.^[9] This area is primarily innervated by the sacral nerve roots S2-S4, with contributions from S1 and S5, providing sensory input for touch, pain, and temperature in these dermatomes.^[3] The cauda equina is a bundle of lumbar and sacral nerve roots (L2-S5) that descends from the conus medullaris, the tapered end of the spinal cord, which typically terminates at the L1-L2 vertebral level in adults.^[9] These nerve roots travel within the lumbar cistern, a subarachnoid space filled with cerebrospinal fluid, and exit the spinal canal through respective intervertebral foramina to form the sacral plexus.^[10] The pudendal nerve, arising from S2-S4, provides key sensory innervation to the perineum, including the external genitalia, anal canal below the pectinate line, and perianal skin.^[11] Additionally, the posterior cutaneous nerve of the thigh, derived from S1-S3, supplies sensation to the buttocks and adjacent perineal skin via its gluteal and perineal branches.^[12] Autonomic fibers within these sacral roots also contribute to visceral sensation and control in the bladder and bowel, though their disruption primarily affects function rather than cutaneous sensation.^[9] Dysfunction in the saddle region arises from the anatomical vulnerability of the cauda equina to compression or injury, particularly at the lumbosacral junction (L4-S1 levels), where the nerve roots are concentrated in a relatively narrow spinal canal without the protective dura of the spinal cord.^[13] These peripheral nerve roots possess a thin epineurium and a proximal hypovascular zone, making them prone to edema and ischemia under compressive forces, which can lead to bilateral or unilateral sensory deficits in the saddle distribution by interrupting multiple adjacent sacral rootlets simultaneously.^[13] Such insults selectively impair perineal sensation while often sparing more proximal lumbar dermatomes.^[3]

Etiology

Cauda Equina and Conus Medullaris Syndromes

Cauda equina syndrome (CES) arises from compression of the lumbosacral nerve roots below the conus medullaris, typically at levels L1-L5, disrupting motor, sensory, and autonomic functions in the lower extremities and perineal region.^[3] The most common etiology is lumbar disc herniation, accounting for approximately 45% of cases, which leads to lower motor neuron signs such as flaccid paralysis, hypotonia, and areflexia in the affected segments.^[3] This compression often involves the sacral roots (S2-S4), which innervate the perineal area, resulting in saddle anesthesia as a hallmark symptom.^[3] Conus medullaris syndrome (CMS), in contrast, involves damage to the conus medullaris at the T12-L2 spinal levels, along with the upper cauda equina, producing a combination of upper and lower motor neuron deficits.^[3] Common causes include tumors or ischemic events, which may lead to symmetric involvement of the legs with hyperreflexia below the lesion and fasciculations at the level of compression.^[3] Saddle anesthesia in CMS tends to be more symmetric due to the central location of the conus, affecting bilateral sacral segments equally.^[14] Key mechanisms underlying both syndromes include central disc prolapse, spinal stenosis, or trauma, which cause impingement on nerve roots or the conus, leading to ischemia or direct mechanical disruption.^[3] In CES, deficits are often asymmetric owing to the peripheral arrangement of nerve roots in the thecal sac, whereas CMS presentations are more symmetric, reflecting the midline spinal cord involvement.^[14] CES represents a primary cause of acute saddle anesthesia, occurring in a substantial proportion of such cases and necessitating urgent evaluation to prevent permanent neurological damage, with decompression ideally within 48 hours.^[3]

Iatrogenic and Traumatic Causes

Iatrogenic causes of saddle anesthesia primarily arise from complications during neuraxial procedures, such as spinal or epidural anesthesia, where direct neurotoxicity from local anesthetics or hematoma formation can compress sacral nerve roots. For instance, high concentrations of lidocaine (e.g., 5% hyperbaric solutions) have been implicated in chemical irritation leading to transient or persistent sensory loss in the perineal area, with mechanisms involving adhesive arachnoiditis or direct neuronal damage.^[13] The incidence of severe neurologic complications like cauda equina syndrome (CES) following spinal anesthesia is estimated at approximately 1:10,000 to 1:20,000 procedures, though epidural hematomas occur even less frequently, at about 1:200,000 in obstetric cases.^[15] Repeated lumbar punctures or chiropractic spinal manipulations can also contribute through mechanical trauma or ischemia, resulting in focal sensory deficits that mimic saddle anesthesia; these are rare but documented in case reports.^[16] Post-procedure saddle anesthesia often presents as a transient phenomenon, resolving within hours due to dilution or clearance of the anesthetic agent, but progression to full CES may occur if an epidural hematoma develops, causing compressive neuropathy on the cauda equina.^[17] Mechanisms include direct needle trauma to nerve roots, inadvertent intrathecal injection of high-volume solutions, or vascular injury leading to bleeding in the confined spinal canal space.^[18] In such cases, early recognition is critical, as delayed intervention can lead to permanent sensory impairment in the S2-S4 dermatomes. Traumatic causes typically involve acute physical injuries that disrupt sacral nerve roots, leading to immediate-onset saddle anesthesia through direct compression or laceration. Spinal fractures, particularly burst fractures at the L1 level, are a common etiology, where retropulsed bone fragments impinge on the cauda equina, often accompanied by vertebral instability that exacerbates nerve root compression.^[19] Penetrating injuries, such as gunshot wounds or stab injuries to the lumbosacral region, can sever or contuse sacral roots, resulting in sensory loss similar to that in CES.^[13] Birth trauma represents another traumatic pathway, particularly in cases of difficult deliveries involving excessive traction on the spine or sacral plexus injury in neonates, affecting sacral roots and potentially causing perineal sensory deficits.^[20] In trauma-related saddle anesthesia, the sensory loss is frequently permanent if associated with complete nerve transection, though partial recovery may occur with decompression in fracture cases; high vertebral instability correlates with poorer outcomes due to ongoing compression.^[21] These etiologies parallel the compressive mechanisms seen in CES but are distinguished by their acute, injury-induced nature.^[13]

Other Causes

Neoplastic causes of saddle anesthesia primarily involve tumors that compress or infiltrate the sacral nerve roots within the cauda equina or conus medullaris. Primary spinal tumors, such as myxopapillary ependymomas and astrocytomas arising from the conus medullaris, often lead to symmetric saddle anesthesia due to direct compression and associated edema disrupting sensory pathways.^[22] Metastatic lesions from systemic cancers, including breast, lung, and prostate carcinomas, can invade the cauda equina, resulting in asymmetric sensory loss in the perineal region as part of cauda equina syndrome.^[23] Additionally, neoplastic polyradiculopathy, as seen in acute myeloid leukemia with leptomeningeal infiltration, may produce saddle anesthesia through diffuse root involvement without a discrete mass.^[23] Infectious and inflammatory etiologies contribute to saddle anesthesia by inducing acute inflammation, abscess formation, or direct neural damage in the lumbosacral region. Epidural abscesses, often from bacterial sources like Staphylococcus aureus, can rapidly compress the cauda equina, manifesting as saddle anesthesia alongside fever and back pain.^[24] Herpes zoster reactivation affecting sacral dermatomes may cause radiculitis with localized vesicular rash and subsequent perianal sensory deficits.^[25] Transverse myelitis, an inflammatory spinal cord disorder frequently idiopathic or post-infectious, can involve the conus medullaris, leading to a sensory level at the saddle area if the lesion is localized there.^[26] Spinal cord infarcts, such as those from anterior spinal artery occlusion, may selectively spare posterior columns but still produce saddle anesthesia when the conus vasculature is affected, mimicking compressive syndromes.^[27] HIV-related vacuolar myelopathy, a degenerative process in advanced infection, can present with progressive sensory ataxia in the lower limbs due to dorsal column demyelination.^[27] Systemic and peripheral conditions underlie saddle anesthesia through demyelination, nutritional deficits, or chronic nerve entrapment. Multiple sclerosis plaques in the sacral spinal cord segments can demyelinate sensory tracts, resulting in patchy or bilateral perineal numbness.^[28] Vitamin B12 deficiency induces subacute combined degeneration of the spinal cord, primarily affecting posterior columns and leading to proprioceptive loss that extends to the saddle region in advanced cases.^[26] Pudendal neuropathy, often from repetitive trauma such as prolonged cycling, causes isolated sensory impairment in the pudendal nerve distribution, presenting as saddle anesthesia without broader cord involvement.^[29] Rare etiologies include historical and iatrogenic factors that selectively target sacral pathways. Tabes dorsalis, a late manifestation of neurosyphilis, produces lightning-like pains and dissociated sensory loss prominently involving the saddle area due to dorsal root ganglion degeneration.^[24] Radiation myelopathy, occurring months to years after spinal irradiation for malignancy, can cause delayed ischemic damage to the conus, resulting in progressive saddle anesthesia.^[30] In the differential diagnosis, Guillain-Barré syndrome may occasionally feature early saddle involvement within its ascending polyradiculoneuropathy pattern, though it typically spares isolated sacral symptoms.^[29]

Clinical Presentation

Sensory Symptoms

Saddle anesthesia is characterized by numbness or hypoesthesia in the perineal, genital, and anal regions, corresponding to the "saddle" distribution innervated by sacral nerve roots S2-S4. This sensory impairment typically involves reduced or absent sensation to pinprick, temperature, and light touch, with vibration sense potentially affected in cauda equina syndrome (CES). In severe cases, it progresses to complete anesthesia, while early manifestations may include paresthesia such as tingling in the affected areas.^[3]^[5] In CES, sensory symptoms often emerge asymmetrically and unilaterally, potentially extending to the lower extremities in lumbar and sacral dermatomes before becoming bilateral as nerve root compression intensifies. By contrast, conus medullaris syndrome (CMS) features more symmetric and bilateral saddle sensory loss from onset, with possible dissociation where pinprick and temperature sensations are impaired but light touch remains relatively preserved. These variations reflect the peripheral (CES) versus central (CMS) nature of the lesions.^[3]^[5] Associated sensory issues include diminished genital sensation, which contributes to sexual dysfunction such as impotence or reduced arousal, and perianal hypoesthesia, increasing vulnerability to undetected injuries like pressure sores or trauma in the sitting area. Progression of saddle anesthesia is acute in 70-80% of CES cases, frequently coinciding with sudden severe low back pain, whereas in demyelinating diseases like multiple sclerosis, it can develop chronically through recurrent inflammatory episodes. Up to 93% of CES patients experience perineal sensory deficits, with persistence noted in 56.6% at 63 days post-surgical decompression.^[3]

Motor and Autonomic Dysfunction

Motor dysfunction in saddle anesthesia, often associated with cauda equina syndrome (CES) or conus medullaris syndrome (CMS), manifests as lower extremity weakness due to compression of lumbosacral nerve roots or the conus medullaris.^[3] In CES, this typically presents as bilateral or unilateral flaccid paralysis with lower motor neuron signs, including hypotonia, areflexia, and muscle atrophy in chronic cases; asymmetrical deficits are common owing to the peripheral nerve root involvement from L1 to S5 levels.^[3] Conversely, CMS may exhibit spastic paralysis with upper motor neuron features like hyperreflexia, reflecting spinal cord compression at T12-L2, though mixed signs can occur.^[3] A classic example is foot drop from L5 nerve root impingement, leading to impaired dorsiflexion and gait instability.^[31] Reduced anal sphincter tone, detectable on digital rectal examination, is a hallmark motor deficit in both syndromes, stemming from S2-S4 root dysfunction and indicating sacral involvement.^[5] The anal wink reflex, elicited by perianal stimulation, is often absent or diminished, serving as a key indicator of sacral nerve integrity loss.^[32] Leg reflexes differ notably: areflexia predominates in CES due to lower motor neuron lesions, while hyperreflexia may appear in CMS from upper motor neuron disruption.^[3] Autonomic dysfunction accompanies motor impairments, primarily affecting bladder, bowel, and sexual functions via parasympathetic and somatic nerve compromise. Urinary retention occurs in 50-70% of CES presentations, often with post-void residual volumes exceeding 100 mL signaling significant detrusor areflexia.^[33]^[34] Bowel dysfunction, including constipation, retention, or fecal incontinence, affects up to 72% of patients, with residual issues persisting in about 42% at two months post-surgery.^[3] In males, erectile dysfunction arises from S2-S4 autonomic fiber disruption, reported in over 50% of cases with incomplete resolution.^[3] Autonomic failures frequently emerge hours to days after initial sensory changes, such as perineal numbness, highlighting disease progression toward complete syndrome and underscoring the need for urgent evaluation.^[33]

Diagnosis

Physical Examination

The physical examination for saddle anesthesia focuses on assessing sensory, motor, reflex, and autonomic functions in the sacral dermatomes to identify deficits indicative of cauda equina syndrome (CES) or related conditions. Sensory testing begins with evaluation of the perianal and perineal regions, often referred to as the "saddle" area, using pinprick for sharp sensation, cotton wool for light touch, and warm/cool objects for temperature discrimination to detect hypoesthesia or anesthesia.^[5] Asymmetry or patchy loss in the buttocks, posterior thighs, and genitals should be noted, as saddle anesthesia may present asymmetrically.^[5] Motor and reflex examinations target lower lumbar and sacral roots. Ankle jerks (Achilles reflex) are tested bilaterally for hyporeflexia or areflexia, which signals S1-S2 involvement.^[5] Digital rectal examination assesses anal sphincter tone by inserting a gloved finger to evaluate voluntary contraction and resting tone; reduced or absent tone indicates sacral nerve dysfunction.^[35] The straight leg raise test is performed to provoke radicular pain or assess for lumbosacral radiculopathy contributing to saddle symptoms, with positive findings at less than 60 degrees suggesting nerve root irritation.^[5] Autonomic function is evaluated through post-void residual bladder volume measurement via ultrasound scan to detect urinary retention (>300 mL), a hallmark of detrusor areflexia in CES, with abnormal results in 80% of confirmed cases.^[35] The bulbocavernosus reflex, elicited by squeezing the glans penis or clitoris while monitoring anal contraction, tests S2-S4 integrity and shows 100% sensitivity and specificity when performed, though it is underutilized.^[35] Red flags during examination include sudden-onset saddle anesthesia accompanied by severe back pain or new-onset incontinence, warranting immediate neurosurgical consultation for potential emergent decompression, as delays beyond 48 hours worsen outcomes.^[7] The sensitivity of perianal sensory testing for CES is approximately 60%, highlighting the need for comprehensive evaluation rather than reliance on a single finding.^[35]

Imaging and Laboratory Tests

Magnetic resonance imaging (MRI) of the lumbosacral spine, often with gadolinium contrast, serves as the gold standard for diagnosing the causes of saddle anesthesia, particularly in suspected cauda equina syndrome (CES), offering high sensitivity for detecting compressive pathologies such as disc herniation, epidural abscess, or tumor.^[36] This modality provides detailed visualization of the conus medullaris, cauda equina, and surrounding structures, enabling identification of nerve root compression or other abnormalities.^[36] If MRI is contraindicated or unavailable, CT myelography is a viable alternative, involving intrathecal contrast to outline the thecal sac and nerve roots with comparable accuracy for localizing lesions.^[36] Laboratory tests support the diagnostic workup by helping to identify infectious or inflammatory contributors to saddle anesthesia, though they are not definitive for CES itself. A complete blood count (CBC) is routinely obtained to detect leukocytosis suggestive of infection, such as in spinal abscesses.^[36] Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels are elevated in inflammatory conditions like discitis or epidural abscess, guiding further evaluation.^[36] Urinalysis is indicated to screen for urinary tract infections or other complications arising from bladder dysfunction and retention.^[36] For chronic presentations of saddle anesthesia, additional specialized tests assess nerve and autonomic integrity. Electromyography (EMG), particularly of the anal sphincter and lower limb muscles, evaluates nerve conduction and detects denervation patterns in sacral roots.^[36] Urodynamic studies quantify bladder pressure, detrusor function, and sphincter coordination, providing critical insights into the extent of autonomic involvement and aiding in prognosis.^[36] Current guidelines emphasize urgent imaging in the presence of red flags such as acute urinary retention or bilateral lower extremity weakness, recommending MRI within 4 hours of clinical suspicion to optimize outcomes and avoid delays exceeding 24 hours, which increase the risk of permanent deficits.^[37]

Management

Acute Treatment

The acute treatment of saddle anesthesia, typically arising from cauda equina syndrome (CES), prioritizes emergent interventions to alleviate neural compression and prevent irreversible deficits in bladder, bowel, and lower limb function. The cornerstone is prompt surgical decompression, which is indicated for patients exhibiting progressive neurological deficits, such as worsening sensory loss in the perineal region or new-onset incontinence.^[7]^[21] Surgical options include laminectomy or discectomy to relieve pressure from causes like massive lumbar disc herniation, with intervention ideally performed within 24 hours of symptom onset and absolutely within 48 hours to optimize neurological recovery. Delaying surgery beyond this window is associated with poorer outcomes, including persistent urinary retention and motor weakness, though some studies indicate benefits even with later decompression in select cases. According to guidelines from the American Association of Neurological Surgeons (AANS), urgent surgery is recommended specifically for CES accompanied by incontinence, as this signals severe root involvement. In cases of iatrogenic causes, such as post-anesthesia hematoma, close monitoring and rapid evacuation are essential to mitigate progression.^[7]^[21]^[38] Supportive measures complement surgery by addressing secondary complications. High-dose corticosteroids, such as dexamethasone 10 mg intravenously, may be administered in non-infectious cases to reduce perineural edema and provide temporary pain relief while awaiting decompression, though evidence for long-term neurological benefit remains limited. For infectious etiologies like epidural abscess, broad-spectrum intravenous antibiotics are initiated immediately, guided by culture results if available. Pain management in the acute phase targets radicular and neuropathic symptoms with opioids for severe discomfort and gabapentinoids like gabapentin to modulate nerve hyperexcitability. Acute urinary retention, a hallmark of CES, requires immediate bladder catheterization—often indwelling initially—to prevent overflow incontinence and renal complications, transitioning to intermittent self-catheterization post-stabilization as needed.^[39]^[40]

Chronic Management

Chronic management of saddle anesthesia, often a residual symptom of cauda equina syndrome (CES), focuses on addressing persistent sensory deficits, motor impairments, and autonomic dysfunction through rehabilitative, pharmacological, and monitoring strategies to improve quality of life.^[3] Rehabilitative therapy plays a central role in mitigating leg weakness and enhancing bladder and bowel control. Physical therapy targets lower limb strength and coordination, incorporating exercises to rebuild muscle stability and gait, which can help patients regain mobility and reduce fall risk following initial recovery.^[41]^[40] Pelvic floor exercises, often guided by biofeedback, strengthen the perineal muscles to alleviate incontinence and improve continence mechanisms in neurogenic bladder and bowel dysfunction.^[42]^[43] Occupational therapy assists with adaptations for daily activities, such as using assistive devices for transfers and self-care, to promote independence despite ongoing sensory loss in the saddle region.^[44] Pharmacological interventions address specific autonomic sequelae. Anticholinergics, such as oxybutynin, are commonly prescribed as first-line therapy for neurogenic bladder overactivity or detrusor-sphincter dyssynergia, reducing urinary urgency and incontinence by inhibiting parasympathetic stimulation of the detrusor muscle.^[45]^[46] For erectile dysfunction, phosphodiesterase-5 inhibitors like sildenafil enhance penile blood flow and improve erection quality in men with neurogenic impairment, with studies showing significant efficacy in CES-related cases.^[47]^[48] Ongoing monitoring ensures timely adjustment of care for evolving symptoms. Regular urodynamic studies evaluate bladder function, detecting issues like detrusor underactivity or high post-void residuals to guide interventions and prevent complications such as urinary tract infections.^[49] Nerve conduction studies assess pudendal and lower sacral nerve integrity, providing objective measures of sensory and motor recovery in the perineal area.^[36] For neuropathic pain, which may persist in the saddle distribution, tricyclic antidepressants like amitriptyline offer analgesia by modulating central pain pathways, with evidence supporting their use in spinal cord injury-related neuropathic conditions.^[50]^[51] A multidisciplinary approach coordinates care across specialties to holistically manage impacts on sexual function and psychological well-being. Neurologists oversee nerve recovery, urologists handle bladder and sexual dysfunction, and psychologists address anxiety or depression from chronic symptoms, with integrated clinics improving outcomes in refractory cases.^[3] For persistent bladder or bowel issues unresponsive to conservative measures, sacral nerve stimulation delivers electrical impulses to the sacral roots, enhancing continence and reducing urgency in select CES patients.^[52]^[53]

Prognosis

Factors Influencing Recovery

The timing of intervention is a key determinant of recovery in saddle anesthesia associated with cauda equina syndrome (CES). Surgical decompression within 24 hours of autonomic symptom onset in incomplete CES (CESI) is linked to superior bladder function outcomes, with 89% of patients achieving normal function at follow-up compared to 53% for those operated after 24 hours. Similarly, decompression within 48 hours yields 84% good bladder recovery rates versus 44% if delayed beyond 48 hours, underscoring the importance of early diagnosis to mitigate permanent deficits. However, some recent studies as of 2025 indicate that surgical timing may not always significantly affect outcomes in all cohorts.^[54]^[55] Etiology-specific factors significantly affect prognosis, with better recovery observed in traumatic or iatrogenic causes compared to neoplastic ones, where ongoing tumor progression limits resolution. In disc herniation-related CES, up to 95% of patients with urinary dysfunction may recover, while neoplastic cases often show poorer long-term outcomes due to persistent compression or metastasis. Younger age (<50 years) and absence of comorbidities, such as diabetes, further enhance recovery prospects, as older patients (≥70 years) face higher risks of residual neurologic deficits.^[56]^[57]^[58] Severity at presentation strongly influences recovery rates, with mild sensory loss absent autonomic failure associated with higher rates of resolution compared to severe presentations, whereas complete perineal anesthesia or significant sphincter involvement correlates with poorer outcomes. Bilateral deficits, typical of complete CES, adversely affect prognosis compared to unilateral or incomplete presentations, increasing the likelihood of persistent sensory and motor impairments.^[59] Longitudinal data highlight variable recovery patterns; for instance, at a 63-day follow-up, approximately 52% of patients achieve micturition recovery, though recovery rates are lower in complete CES cases.^[60]

Potential Complications

Saddle anesthesia, when associated with untreated or incompletely resolved cauda equina syndrome, can lead to persistent neurological residuals, including chronic numbness in the perineal and saddle regions. Studies indicate that up to 29% of patients experience ongoing saddle anesthesia 3 to 5 years post-surgery, while genital numbness persists in approximately 47% of cases at a mean follow-up of nearly 5 years.^[61]^[62] Chronic neuropathic pain, particularly lower back pain, affects around 67% of patients long-term, often requiring further medical intervention in 10% of cases.^[62] Additionally, lower limb weakness contributes to mobility limitations, with up to 40% of working-age individuals unable to return to employment due to persistent motor deficits.^[62] Urological and bowel complications are common sequelae, with chronic bladder dysfunction reported in 33% to 42% of patients at long-term follow-up, manifesting as urinary incontinence or retention.^[62]^[61] Bowel dysfunction, including fecal incontinence and constipation, persists in 38% to 44% of cases, sometimes leading to severe fecal impaction.^[62]^[61] These issues increase the risk of recurrent urinary tract infections due to incomplete bladder emptying or catheterization needs.^[7] In severe, refractory instances, bowel management may necessitate colostomy to address chronic incontinence or impaction.^[63] Sexual dysfunction represents a significant long-term impact, affecting 53% to 64% of patients overall, with impotence or erectile difficulties occurring in up to 59% of males due to impaired orgasmic and erectile function.^[62]^[61]^[64] In females, dyspareunia may arise from perineal sensory loss.^[65] Psychological consequences include depression, with 50% of patients experiencing moderate or severe symptoms stemming from functional losses and chronic pain.^[62] Leg weakness further elevates fall risk, exacerbating mobility challenges and injury potential.^[66] In immunocompromised patients, secondary infections such as urinary tract or wound complications can arise more readily due to autonomic dysfunction and hospitalization needs.^[7]^[67]

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Suspected cauda equina syndrome: no reduction in investigation ...
... cauda equina syndrome (CES), . ... However, 70–80% of patients have severe, acute onset pain, bladder, bowel or ...
[32]
Acute bilateral foot drop with or without cauda equina syndrome—a ...
Feb 7, 2021 · We present 7 cases of acute and bilateral foot drop, all due to degenerative spinal disease, with trauma and relevant systemic illness excluded as causes.
[33]
Anal reflex versus bulbocavernosus reflex in evaluation of patients ...
Jan 7, 2020 · The anal reflex is also known as the anal wink ... Clinical assessment of cauda equina syndrome and the bulbocavernosus reflex (letter).
[34]
Cauda equina syndrome: a review of the current clinical and medico ...
Red flag symptoms of cauda equina syndrome (CES): typically from a central PID. Usually severe LBP and bilateral neurogenic sciatica. Perineal/genital numbness.Missing: paresthesia | Show results with:paresthesia
[35]
Bladder Post Void Residual Volume - StatPearls - NCBI Bookshelf
A PVR over 400 mL is considered abnormal and generally diagnostic of urinary retention. In addition, it may be highly predictive of cauda equina syndrome if ...
[36]
Physical Examination Is Predictive of Cauda Equina Syndrome - NIH
A combination of physical examination findings of lower sacral function is an effective means of ruling out CES and, with further study, may eliminate the need ...
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Cauda Equina and Conus Medullaris Syndromes Workup
Dec 30, 2024 · MRI with gadolinium contrast of the lumbosacral area is the diagnostic test of choice to define pathology in the areas of the conus medullaris ...Approach Considerations · Radiography · Magnetic Resonance Imaging
[38]
[PDF] National Suspected Cauda Equina Syndrome (CES) Pathway - GIRFT
MRI protocol: The 24/7 Cauda Equina Syndrome MRI screening protocol should prioritise this sequence. This is typically a 2D turbo spin echo sequence. There is ...
[39]
Cauda equina syndrome—a practical guide to definition and ... - NIH
Dec 4, 2021 · Cauda equina syndrome (CES) is a rare but important condition whose commonest cause is massive lumbar disc herniation compressing the roots of the cauda equina.Missing: paresthesia | Show results with:paresthesia
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Cauda Equina syndrome - PMC - PubMed Central - NIH
Treatment with high-dose steroids (dexamethasone 4–100 mg IV) may provide pain relief and improved neurologic function (by reducing edema) while awaiting ...
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Cauda Equina Syndrome: What It Is, Symptoms & Treatment
Cauda equina syndrome is nerve root compression that causes pain, weakness and incontinence. It's a medical emergency.Missing: anesthesia | Show results with:anesthesia
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Cauda Equina Syndrome - Physiopedia
The most common cause of compression in 45% of CES is a herniated lumbar intervertebral disc. Other causes include epidural abscess, spinal epidural hematoma, ...
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[PDF] Rehabilitation in a case with cauda equina syndrome after spinal ...
Oct 31, 2024 · Saddle anesthesia is another challenge in the long-term management of cauda equina syndrome. It also leads to sexual dysfunction and is ...
[44]
[PDF] Effectiveness of Pelvic Floor Exercises Along with Faradic ...
Feb 21, 2022 · Physiotherapy treatment such as pelvic floor exercises and electro- therapy can help the patient to overcome the symptoms and reduce the ...<|separator|>
[45]
Rehabilitation after cauda equina injury – what you need to know
Oct 15, 2025 · This rehab could involve re-learning to walk, balance and coordinate lower limbs, which may mean using assistive devices such as crutches, ...
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Neurogenic Bladder and Neurogenic Lower Urinary Tract Dysfunction
Patients with significant detrusor overactivity should initially be treated with behavioral modifications and pharmacotherapy, including anticholinergics and/or ...
[47]
Neurogenic Lower Urinary Tract Dysfunction: AUA/SUFU Guideline ...
Neurogenic lower urinary tract dysfunction (NLUTD) refers to abnormal function of either the bladder, bladder neck, and/or its sphincters related to a ...
[48]
Efficacy and Safety of Sildenafil in Men With Sexual Dysfunction and ...
Sildenafil significantly improves erections, intercourse success, and ejaculation frequency vs placebo, including in men with complete SCI.
[49]
Phosphodiesterase inhibitors in the treatment of erectile dysfunction ...
Sildenafil, Vardenafil and Tadalafil are all effective and well-tolerated treatments for ED in SCI patients.
[50]
The role of urodynamic assessment in cauda equina syndrome ...
Sep 10, 2022 · Urodynamically, LUT dysfunction in CES typically involves underactive or acontractile bladder with sphincter underactivity, which result in incomplete bladder ...Missing: EMG | Show results with:EMG<|separator|>
[51]
Management of Neuropathic Pain Associated with Spinal Cord Injury
Amitriptyline, a tricyclic antidepressant and the antiepileptic drugs, gabapentin and pregabalin, are most studied with demonstrated efficacy.
[52]
Antidepressants in the treatment of neuropathic pain - PubMed
Tricyclic antidepressants will relieve one in every 2-3 patients with peripheral neuropathic pain, serotonin noradrenaline reuptake inhibitors one in every 4-5 ...
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Sacral Nerve Stimulation for Treatment of Intractable Pain ... - NIH
Sacral nerve stimulation (SNS) is an effective treatment for bladder and bowel dysfunction, and also has a role in the treatment of chronic pelvic pain.
[54]
(PDF) Sacral Nerve Stimulation for Treatment of Intractable Pain ...
Aug 9, 2025 · We report two cases of intractable pain associated with cauda equina syndrome (CES) that were treated successfully by SNS.
[55]
Does early surgical decompression in cauda equina syndrome ...
Apr 15, 2015 · We identified that decompressive surgery within 24 hours of onset of autonomic symptoms in CESI reduces bladder dysfunction at initial follow-up.
[56]
Cauda equina syndrome secondary to lumbar disc herniation
Conclusions: There was a significant advantage to treating patients within 48 hours versus more than 48 hours after the onset of cauda equina syndrome.Missing: recovery rates
[57]
Prognosis of Cauda Equina Syndrome Caused by Herniated Disk ...
About 24-month follow-up of patients showed muscle weakness improvement in 26(78.8%) of them. Of all 19 patients with urinary dysfunction, 18(94.7%) recovered.
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Risk factors for residual neurologic deficits after surgical treatment ...
Patients' neurologic status improved significantly after the surgery (p<.001). Risk factors including age, diabetes, cauda equina syndrome, presence of ...Missing: prognosis recovery
[59]
Predictors of outcome in cauda equina syndrome - PubMed
The mean time to decompression in the group with a satisfactory outcome was 14 h (range 6-24 h) whilst that of the group with the poor outcome was 30 h (range ...
[60]
Cauda Equina Syndrome: presentation, outcome, and predictors ...
Two post-operative follow-up (FU) moments took place after a mean of 75 h and 63 days. Outcomes at second FU moment: micturition dysfunction 48%, defecation ...Missing: bladder | Show results with:bladder<|control11|><|separator|>
[61]
How to assess the long-term recovery outcomes of patients with ...
After 3 to 5 years of follow-up, the residual rates of bladder dysfunction, bowel dysfunction, sexual dysfunction, and saddle anesthesia were 41.9, 44.1, 63.7, ...
[62]
Long-term core outcomes in cauda equina syndrome | Bone & Joint
Sep 1, 2021 · This study assesses the recently defined core outcome set for CES in a cohort of patients using validated questionnaires.
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[PDF] Colostomy - Spinal Injuries Association
Some people with a spinal cord injury (SCI) or Cauda Equina Syndrome. (CES) consider having a colostomy as it may give them more independence and can be truly ...Missing: fecal impaction
[64]
Sexual function in men with cauda equina lesions - NIH
Results: Severe sexual dysfunction was reported by 35% of patients, moderate dysfunction by 24%, and slight dysfunction by 26%; normal sexual function was ...
[65]
Cauda Equina Syndrome: Why do we miss it? How to improve?
Jun 13, 2021 · CES results from compression of lower lumbar and sacral nerve roots, with L4-L5 disc herniation as the most common etiology. While CES is ...
[66]
Living with cauda equina syndrome – things you might need to know.
Feb 19, 2024 · It happens when the nerve roots in the lumbar spine are compressed, cutting off sensation and movement. CES is not a permanent disability itself ...Missing: persistent | Show results with:persistent
[67]
Atypical Spinal Infections in Immunocompromised Patients
Spinal infections in immunocompromised patients are a potential threat due to atypical presentations and delay in diagnosis.