History

Fact Explanation
Introduction Cauda equine syndrome [CES] is a collection of clinical features that results from the compression of the cauda equina, which is the lowermost part of the spinal cord comprising of the lumbosacral roots [1]. The compression of the motor & sensory nerve roots supplying the lower limb, bladder, rectum, sphincters and the sexual organs gives rise to a collection of signs & symptoms related to their dysfunction [2]. The causative factors of compressing the cauda equina include central/ centrolateral disc prolapse, spinal stenosis ans spinal neoplasms [2]. The non-compressive causes include ischemic insults, spinal arachnoiditis [2] infections such as meningitis, as a complication after surgery/ anesthetic procedures / spinal manipulation and epidural injections [3]. Lumbar disc herniation is the most common cause [4], with the herniation most commonly at L4/L5 or L5/S1 level [5]. The compression/ischemia causes impairment of impulse propagation and change of neurotransmitters in the spinal cord, leading to the motor/sensory impairment resulting in CES [2].
Symptoms of bladder dysfunction Patients commonly present with bladder problems due to the compression of S2,S3,S4 nerve roots which is the main innervation of the bladder and the urethral sphincter, and the most common symptoms include painless urinary retention and overflow incontinence. However, some patients may not present with bladder symptoms [3]. In incomplete CES, patients may have altered urinary sensation, loss of desire to void and poor urinary stream due to loss of bladder innervation[4]. Note: asking for bladder symptoms is a very important component of the history before excluding CES [3].
Symptoms of bowel dysfunction This also results from the dusfunction of S2, S3 & S4 nerve roots that innervate the rectum and the anus. Patients do not present commonly with bowel symptoms as the bladder symptoms, and include non-specific symptoms ranging from constipation to incontinence. However, these symptoms may not be apparent in the acute stage due to loss of sensation in complete CES [3]. Important: as the the bladder & bowel symptoms have a gradual onset it is important to monitor for bladder & bowel symptoms in suspected CES [3].
Anesthesia of the perianal area Most of the patients present with anesthesia of the perianal area [6]. There is only partial/ unilateral loss of saddle/ genital sensation in incomplete CES, with preserved sensation of the trigone area [1].
Weakness of lower limbs Although motor dysfunction is not a feature of classic CES, patients may present with lower limb weakness [4]. Therefore it is important to ask this in the history of suspected CES.
Sexual dysfunction Although not a common clinical finding of CES, patients may have sexual dysfunction. Thus patients should be inquired about erectile dysfunction, impotence & ejaculatory dysfunction [3]. Note: As patients are reluctant to express problems in their sexual function, it is the responsibility of the physician to obtain the relevant details from the patient as it helps in early and proper diagnosis [3].
Lower back pain Severe lower back pain is quite a rare symptom in cauda equina syndrome, with only 1 in 2000 patients presenting with this symptom [3]. Sciatica may be associated with the back pain and often bilateral when present. However, sciatica may be absent when the compression is at or below the level of L5/S1 [1]. Important: if a patient presenting with back pain is having bladder & bowel symptoms and/or motor/sensory deficit in the pelvis and the lower limbs, CES should be suspected always [7]. Severe lower back pain, sciatica, bladder, bowel & sexual dysfunction and saddle/genital sensory impairment are regarded as red flag symptoms and immediate action is needed in view of management [1].
Lower limb pain This is not a common symptom and is non-specific. When present, lower limb pain is regarded as a poor prognostic factor of CES. When the compression is caused by a central disc herniation, the lateral lumbar nerve roots are spared hence symptoms of lower limb pain will be absent [3].
References
  1. GARDNER ALAN, GARDNER EDWARD, MORLEY TIM. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J [online] December, 20(5):690-697 [viewed 08 September 2014] Available from: doi:10.1007/s00586-010-1668-3
  2. ORENDáčOVá JUDITA, Čı́žKOVá DášA, KAFKA JOZEF, LUKáčOVá NADEžDA, MARšALA MARTIN, ŠULLA IGOR, MARšALA JOZEF, KATSUBE NOBUO. Cauda equina syndrome. Progress in Neurobiology [online] 2001 August, 64(6):613-637 [viewed 11 September 2014] Available from: doi:10.1016/S0301-0082(00)00065-4
  3. FRASER STUART, ROBERTS LISA, MURPHY EVE. Cauda Equina Syndrome: A Literature Review of Its Definition and Clinical Presentation. Archives of Physical Medicine and Rehabilitation [online] 2009 November, 90(11):1964-1968 [viewed 08 September 2014] Available from: doi:10.1016/j.apmr.2009.03.021
  4. KORSE N. S., JACOBS W. C. H., ELZEVIER H. W., VLEGGEERT-LANKAMP C. L. A. M.. Complaints of micturition, defecation and sexual function in cauda equina syndrome due to lumbar disk herniation: a systematic review. Eur Spine J [online] December, 22(5):1019-1029 [viewed 08 September 2014] Available from: doi:10.1007/s00586-012-2601-8
  5. LAVY C., JAMES A., WILSON-MACDONALD J., FAIRBANK J.. Cauda Equina Syndrome. Obstetric Anesthesia Digest [online] 2010 March, 30(1):16-17 [viewed 11 September 2014] Available from: doi:10.1097/01.aoa.0000366996.87147.18
  6. GOLOB ANNA L., WIPF JOYCE E.. Low Back Pain. Medical Clinics of North America [online] 2014 May, 98(3):405-428 [viewed 08 September 2014] Available from: doi:10.1016/j.mcna.2014.01.003
  7. CASAZZA BA. Diagnosis and treatment of acute low back pain. Am Fam Physician [online] 2012 Feb 15, 85(4):343-50 [viewed 08 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/22335313

Examination

Fact Explanation
Motor examination of the lower limbs Although motor signs are not a feature of classic CES as the lumbar roots that gives motor supply to the lower limbs are usually spared in CES, weakness of lower limbs is found in most of the patients with CES [1]. Also, straight leg raising test may be abnormal [2]. Therefore, motor examination should be carried out in all the patients suspected of CES [1]. As reflexes of the lower limbs may be affected as well in some patients, it is advised to check for reflexes in the motor examination. The reflexes are diminished as the lower motor neurones are affected [1].
Sensory examination of the pelvis Testing for both light touch and pin-prick sensation is a must in any person suspected of CES [1]. The most common findings are anesthesia of the perineum & the saddle area [4]. Note: saddle anesthesia with sphincter dysfunction is known to be the most striking feature of CES [1], and complete perianal anesthesia at the presentation is considered to be a poor prognostic factor [5].
Digital examination of the rectum (DER) This should be done in every patient to asses for the anal tone and reflex contracture, as it helps in early diagnosis CES. However, most of the patients presenting with bladder & bowel symptoms have normal findings in the DER [1].
Abdominal examination Palpable bladder may be present due to urinary retention [6].
Complications of the condition It is necessary to be alert on deep vein thrombosis and pressure ulcers as a complication of CES, due to prolonged immobilization. The patient may complaint of severe pain on calf muscle and signs include tenderness, warmth, erythema & swelling of the leg [3].
References
  1. FRASER STUART, ROBERTS LISA, MURPHY EVE. Cauda Equina Syndrome: A Literature Review of Its Definition and Clinical Presentation. Archives of Physical Medicine and Rehabilitation [online] 2009 November, 90(11):1964-1968 [viewed 08 September 2014] Available from: doi:10.1016/j.apmr.2009.03.021
  2. Goertz M, Thorson D, Bonsell J, Bonte B, Campbell R, Haake B, Johnson K, Kramer C, Mueller B, Peterson S, Setterlund L, Timming R. Institute for Clinical Systems Improvement. Adult Acute and Subacute Low Back Pain. Updated November 2012. [viewed 08 September 2014] Available from: http://www.icsi.org/guidelines_and_more/gl_os_prot/musculo-skeletal/low_back_pain/low_back_pain__adult_5.html.
  3. WILBUR J, SHIAN B. Diagnosis of deep venous thrombosis and pulmonary embolism. Am Fam Physician [online] 2012 Nov 15, 86(10):913-9 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/23157144
  4. GOLOB ANNA L., WIPF JOYCE E.. Low Back Pain. Medical Clinics of North America [online] 2014 May, 98(3):405-428 [viewed 08 September 2014] Available from: doi:10.1016/j.mcna.2014.01.003
  5. KENNEDY J. G., SOFFE K. E., MCGRATH A., STEPHENS M. M., WALSH M. G., MCMANUS F.. Predictors of outcome in cauda equina syndrome. European Spine Journal [online] 1999 August, 8(4):317-322 [viewed 08 September 2014] Available from: doi:10.1007/s005860050180
  6. SELIUS BA, SUBEDI R. Urinary retention in adults: diagnosis and initial management. Am Fam Physician [online] 2008 Mar 1, 77(5):643-50 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18350762

Differential Diagnoses

Fact Explanation
Infection (Spinal tuberculosis/Pyelonephritis/ spinal epidural abscess/ vertebral osteomyelitis) These can also cause lower back pain. However, spinal tuberculosis is uncommon in developed countries. The gradual onset of symptoms with the association of fever may help in excluding the diagnosis of CES [1].
Vertebral fracture This can give rise to acute onset back pain similar to CES. A radiograpg of the spine can help in identifying the fracture and making the right diagnosis [1].
Opiate analegesia When patients with lower back pain and limb pain are on opiates for pain relief, they may complaint of urinary retention mimicking CES, as the opiates have an effect on the sphincter function. history of opiate use combined with quick recovery of bladder function and normal neurological examination excludes CES [2].
Malignancy Breast/ lung/ prostrate/thyroid/ gut and renal malignancy can give rise to spinal metastasis leading to lower back pain. The gradual onset of symptoms and history of malignancy may help in making the diagnosis [1].
Prostatomegaly This causes urinary symptoms in elderly males [2]. The progressive onset of symptoms with normal neurological findings and ultrasound scan findings help in the diagnosis.
Post surgical urinary retention due to anesthetic effect This causes a temporary retention of urine and the history also helps in excluding the diagnosis of CES [2].
Guillan Barre syndrome (GBS) Patients present with weakness of lower limbs and examination reveals lower motor neurone type of lesion with reduced muscle power and diminished reflexes [3]. Urinary retention is also a feature [4]. Ascending weakness with involvement of other cranial nerves (facial nerve), and electromyelogram helps in making the diagnosis [3].
Diabetic neuropathy This also causes peripheral sensory impairment as well as bladder dysfunction due to autonomic neuropathy, causing retention and overflow incontinence similar to CES [5]. History of diabetes and presence of other complications of diabetes aids in making the diagnosis.
Multiple sclerosis This causes urinary retention, sexual dysfunction and weakness of limbs similar to CES, but the reflexes are exaggerated as opposed to CES [6].
Transverse myelitis This is an upper motor neurone lesion causesing motor & sensory impairment of acute onset with bladder & bowel dysfunction. Hyper reflexia and presence of babinsky reflex in the examination aids in differentiating it from CES [7].
References
  1. Goertz M, Thorson D, Bonsell J, Bonte B, Campbell R, Haake B, Johnson K, Kramer C, Mueller B, Peterson S, Setterlund L, Timming R. Institute for Clinical Systems Improvement. Adult Acute and Subacute Low Back Pain. Updated November 2012. [viewed 08 September 2014] Available from: http://www.icsi.org/guidelines_and_more/gl_os_prot/musculo-skeletal/low_back_pain/low_back_pain__adult_5.html.
  2. Gloucestershire Hospitals. NHS Foundation Trust. Cauda Equina Syndrome (CES) - Early Recognition.Physiotherapy Guideline. Reviewed July 2014. [viewed 08 September 2014] Available from: ESPPN_Protocols_etc__GHNHSFT_Physiotherapy_Guideline_Cauda_Equina_Syndrome_2012%20(1).pdf.
  3. NEWSWANGER DL, WARREN CR. Guillain-Barré syndrome. Am Fam Physician [online] 2004 May 15, 69(10):2405-10 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/15168961
  4. SELIUS BA, SUBEDI R. Urinary retention in adults: diagnosis and initial management. Am Fam Physician [online] 2008 Mar 1, 77(5):643-50 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18350762
  5. ARING AM, JONES DE, FALKO JM. Evaluation and prevention of diabetic neuropathy. Am Fam Physician [online] 2005 Jun 1, 71(11):2123-8 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/15952441
  6. CALABRESI PA. Diagnosis and management of multiple sclerosis. Am Fam Physician [online] 2004 Nov 15, 70(10):1935-44 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/15571060
  7. FROHMAN ELLIOT M., WINGERCHUK DEAN M.. Transverse Myelitis. N Engl J Med [online] 2010 August, 363(6):564-572 [viewed 12 September 2014] Available from: doi:10.1056/NEJMcp1001112

Investigations - for Diagnosis

Fact Explanation
Magnetic resonance imaging of the spine (MRI spine) Emergency MRI spine should be carried out as soon as possible to prevent delay in diagnosis [1]. Obliterated spinal canal by the herniated disc/ intraspinal mass can be seen in the MRI, confirming the diagnosis [2].
Computed tomography of spine (CT spine) This is recommended when MRI spine is not accessible [3].
Urodynamic tests Useful in assessing bladder dysfunction and aids in the early diagnosis of CES. The ultra sound scan findings include large volumes of urine in post void residual testing despite no bladder complaints [3].
Spinal radiograph Helpful in excluding the differential diagnosis of vertebral fracture [4].
Electromyelogram Helps in excluding the diagnosis of GBS and other related muscle problems [5].
Erythrocyte sedimentation rate/ C reactive protein Helps to exclude inflammatory and other infective conditions such as GBS [5].
Capillary blood sugar/ HbA1C Useful in assessing the blood sugar in suspected/known diabetics as a guide to diagnosis. HbA1C gives an impression on the long term glucose control and used as a screening method for diabetes [6].
References
  1. GARDNER ALAN, GARDNER EDWARD, MORLEY TIM. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J [online] December, 20(5):690-697 [viewed 08 September 2014] Available from: doi:10.1007/s00586-010-1668-3
  2. THEYS TOM, KHO KUAN H.. The Saddle and the Horse’s Tail. JAMA Neurol [online] 2014 July [viewed 08 September 2014] Available from: doi:10.1001/jamaneurol.2013.6008
  3. FRASER STUART, ROBERTS LISA, MURPHY EVE. Cauda Equina Syndrome: A Literature Review of Its Definition and Clinical Presentation. Archives of Physical Medicine and Rehabilitation [online] 2009 November, 90(11):1964-1968 [viewed 08 September 2014] Available from: doi:10.1016/j.apmr.2009.03.021
  4. Goertz M, Thorson D, Bonsell J, Bonte B, Campbell R, Haake B, Johnson K, Kramer C, Mueller B, Peterson S, Setterlund L, Timming R. Institute for Clinical Systems Improvement. Adult Acute and Subacute Low Back Pain. Updated November 2012. [viewed 08 September 2014] Available from: http://www.icsi.org/guidelines_and_more/gl_os_prot/musculo-skeletal/low_back_pain/low_back_pain__adult_5.html.
  5. NEWSWANGER DL, WARREN CR. Guillain-Barré syndrome. Am Fam Physician [online] 2004 May 15, 69(10):2405-10 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/15168961
  6. PATEL P, MACEROLLO A. Diabetes mellitus: diagnosis and screening. Am Fam Physician [online] 2010 Apr 1, 81(7):863-70 [viewed 11 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20353144

Investigations - Followup

Fact Explanation
MRI spine This may be needed in the post surgical period to evaluate the condition, if the clinical features continue to persist.
Urodynamic tests These may be needed in the long term if the patients are left with residual urinary symptoms.
References

Management - General Measures

Fact Explanation
Prompt & early diagnosis and early referral to specialist care Early diagnosis and prompt action is mandatory in the outcome of the CES. Hence physicians should be well aware about the red flag symptoms and make necessary steps for early referral to a specialist unit to prevent delay in specific treatment and thereby offer the patient a good outcome [1].
Patient education & counseling This is a very crucial aspect in the management to avoid unpleasant medico-legal issues which are notorious with the CES [2]. The patient and the relatives should be explained about the condition and its short term & long term prognosis. Consent should be taken for surgery after explaining the possible residual neurological deficits that are likely to persist post surgery [1].
Treatment of the underlying cause The underlying cause that led to the CES should be investigated and treated to prevent recurrence.
Treatment of complications Complications of CES such as pressure ulcers, deep vein thrombosis should be assessed and appropriate measures should be taken to prevent progression.
Follow-up care This should be carried out by a multi-disciplinary team (MDT) involving the neuro- surgery unit, urologist/gynecologist, physiotherapist, occupational therapist, gastroenterologist and a social worker [1]. About 20% of patients with poor prognostic factors may need continuing care and support for self-catheterization, management of sexual dysfunction, colostomy, urological & gynecological surgery [1]. The aim of follow-up is to rehabilitate the patient to become independent and to provide good quality of life.
Physiotherapy Physiotherapy is necessary in the early period for recovery of motor functions.
Occupational therapy Some patients may not be able to go back to their previous occupations or may need assistance, thus occupational therapy should be carried out as well.
Psychological support As this can cause devastating effects to the quality of life of the patient, affecting his work & income/ personal & sexual life, the patient and the family members should be offered psychological support to overcome/ prevent depression and stress as a consequence of the condition.
Social support The social worker has an important role in the assessment of the living conditions of the patient and identifying the areas of help required and making the necessary arrangements in order to give better quality of care and social support to the patient.
References
  1. GARDNER ALAN, GARDNER EDWARD, MORLEY TIM. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J [online] December, 20(5):690-697 [viewed 08 September 2014] Available from: doi:10.1007/s00586-010-1668-3
  2. THEYS TOM, KHO KUAN H.. The Saddle and the Horse’s Tail. JAMA Neurol [online] 2014 July [viewed 08 September 2014] Available from: doi:10.1001/jamaneurol.2013.6008

Management - Specific Treatments

Fact Explanation
Decompressive surgery Emergency decompression is indicated in CES as the clinical features become apparent when the cauda equina is severely compressed [1]. The recovery of the bladder function is most likely to be found in patients who underwent surgery less than 24 hours after the onset of symtoms [2].
Post-operative care A sympathetic approach should be followed with supportive care given for the patient and the family members [2] . Initial bed rest should be carried out post surgery until recovery of bladder & bowel function. Long term follow-up and rehabilitation is discussed in the general management.
References
  1. KORSE N. S., JACOBS W. C. H., ELZEVIER H. W., VLEGGEERT-LANKAMP C. L. A. M.. Complaints of micturition, defecation and sexual function in cauda equina syndrome due to lumbar disk herniation: a systematic review. Eur Spine J [online] December, 22(5):1019-1029 [viewed 08 September 2014] Available from: doi:10.1007/s00586-012-2601-8
  2. GARDNER ALAN, GARDNER EDWARD, MORLEY TIM. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J [online] December, 20(5):690-697 [viewed 08 September 2014] Available from: doi:10.1007/s00586-010-1668-3