Cauda Equina Syndrome Changing Perceptions

1. CaudaEquina SyndromeChanging Perceptions Manoj Krishna Spinal Surgeon www.spinalsurgeon.com

2. What is CaudaEquina Syndrome • Severe neurological disorder caused by compression or disturbance of function of the caudaequina • The CaudaEquina is a sheath of nerves arising from the tip of the spinal cord( The conus) • These include the L1-5 and S1-5 nerve Roots

3. Causes • Large central disc protrusion- most common-2% of all disc protrusions • Severe Spinal Stenosis • Epidural Abscess • Fractures at T12/L1 level • Tumours of the Conus • Epidural Haematoma( Spinal anaesthesia, bleeding disorders)

4. Symptoms • Bladder Dysfunction: Retention, Overflow incontinence, hesitancy, urgency • Unilateral or bilateral leg pain • Saddle sensory loss- one or both buttocks • Low Back Pain • Motor Weakness • Late Stages: Bladder and Bowel Incontinence, Sexual dysfunction, paraplegia.

5. Bladder Anatomy • Neurophysiologically, lesions involving the cauda equina are lower motor neuron lesions. Therefore, patients with CES may demonstrate varying degrees of lower extremity muscle weakness and sensory disturbance as well as decreased or absent reflexes. • Neurogenic bladder dysfunction is an essential element of CES. • The detrusorurinae muscle and internal sphincter of the bladder are smooth muscles. They are controlled by the parasympathetic nervous system via the S 2-4 nerve roots and the sympathetic nervous system via the hypogastric plexus (T11-L3). • The external sphincter of the bladder is a striated muscle that is controlled by the pudendal nerve, which arises from the S2-4 • Bladder dysfunction can be divided into two broad categories: retention and incontinence. • CES causes a lower motor neuron lesion that interrupts the nerves forming those reflex arcs. Consequently, patients lose both sensory and motor innervation to the bladder. • The loss of contraction and sensation leads to urinary retention and eventually to overflow incontinence.

6. 2 Distinct Presentations • The acute presentation was characterized by the sudden onset of severe low back pain, sciatica, urinary retention requiring catheterization, motor weakness of the lower extremities, and perinealanesthesia. • The insidious presentation was characterized by recurrent episodes of low back pain occurring over periods of a few weeks to years, followed by the gradual onset of sciatica, sensorimotor loss, and bowel and bladder dysfunction. This latter presentation often occurs in the setting of long-standing spinal stenosis.

7. Changing Management • We now want to intervene early- before a full blown syndrome develops- because then its usually too late for recovery. Early surgery results in a full recovery. • REFER EARLY IF: Patient has any bladder dysfunction, associated with any altered sensation in buttocks and sciatica(one or both legs) • Patient needs an Urgent MRI scan and surgery within 24 hours if a large disc prolapse is present

8. SIGNS Sensation to pinprick in the perianal region (S2-S4 dermatomes), perineum, and posterior thigh is performed. These patients typically have preserved sensation to pressure and light touch, so if discrimination is not made between pinprick and light touch sensation, then the diagnosis of CES may be missed. Altered sensation rather than absent sensation is the key to an early diagnosis. A rectal examination is performed on all patients with potential CES to assess the tone and voluntary contracture of the external anal sphincter. Decreased rectal tone is often an early finding in a patient with CES. Both the anal wink test and a bulbocavernosusreflex should be evaluated. The bulbocavernosus reflex is a segmental polysynaptic reflex with crossover in the sacral spinal cord (S1-3). The reflex is performed by applying pressure to the glans penis or clitoris and/or traction on the Foley catheter- this causes a contraction of the rectal sphincter. This is a superficial reflex and is lost early in CES

9. DERMATOMES

10. Bulbocavernous reflex

11. Treatment- 3 cases studies • Surgery within 24 hours gives best outcome • In my experience an interbody fusion gives better outcomes than a discectomy because it removes the pain source, decompresses the neural structures and restores loading across the disc space • A discectomy is another option practised by many surgeons

12. JC. F=30. Cauda Equina Syndrome. All disc material H/O Fall down stairs. Numb buttocks and sciatica. Dribbling. Referred 10 days after onset. Delayed diagnosis . Post- discectomy pain went. Bladder function improved.Numbness still. Poor anal tone.

13. MC. F= 12/50. Central Disc Prolapse L5/S1. 16/10/97 Central Disc prolapse Oct 97, sudden severe LBP, dribbling urine and Rt Leg Pain. Symptoms settled in one week, but then recurred . Central disc prolapse L5/S1, causing an irritable bladder and LBP. Sitting a problem.

14. MC. F= 12/50. Central Disc Prolapse L5/S1. L5/S1 PLIF on 19/8/98. Complete relief of LBP and Leg Pain 17/11/98

15. JR. Cauda Equina Syndrome. Obese F. 48. h/o LBP 5 yrs. Then bilateral sciatica and bladder dysfunction.

16. JR. Cauda Equina Syndrome. L4/5 PLIF. Complete relief of pain + bladder function. Saddle sensory loss recovered.