CASE STUDIES M Steffen M Sc Physiotherapy (Witwatersrand), Private Practitioner INTRODUCTION C aud a E quina Synd rom e (CES) is the m ost severe o f the m any nerve com pres­ sion synd rom es that occu r in the lum bar spine. Its clinical p resentation is w h at d if­ fe r e n tia te s it fro m o th e r lu m b a r s y n ­ d rom es. The signs and sym p tom s are de­ pendent upon the level, the severity o f the m yelopathy, and the acuteness o f its onset. DEFINITION C au d a E quina Synd rom e is a pelvic vis­ ceral d y sfu n ctio n associated w ith com ­ pression o f the cauda equ in a1. EXPLANATION T he sy nd rom e can presen t as acu te or chronic, partial or com plete, at a h igh lum ­ bar level o r at the lum bosacral ju nction. If the com pression is at the lum bosacral ju n c­ tion, the only find ings w ill b e perineal nu m bn ess, pelvic floor paralysis, dysfunc­ tion o f bow el and bladder, and loss o f sex u a l fu n ctio n . If the c o m p re ssio n o f cauda equina takes place at a higher level in the lum bar spine, then partial or com ­ plete paralysis o f the legs m ay also be pre­ sent. • A etiology - com m on ly becau se of: * m assive disc herniation, often in a narrow canal (acute) * s e v e r e s p in a l s te n o s is fro m an y cause (chronic) PATIENT PRESENTATION • A cute Cauda Equina Synd rom e This m ay be caused b y m any different com pressive lesions o f the cauda equina. These include tum ours, infections, frac­ tures and disc herniations. The highest in ­ cidence is found to be due to m assive disc herniation, often in a narrow spinal canal2. The m ajority o f lesions at L4/5 and L 5/SI A cute is classified into 3 groups: G roup I - sud d en onset - no prem oni­ tory sym ptom s, no w arning G roup II - previou s h istory o f sciatica and back pain prior to acute onset o f uri­ nary retention i.e. pelvic v isceral paralysis G roup III - back pain and sciatica, uni­ laterally or bilaterally - after short interval develop urinary retention3. The difference betw een G roups II and III is the time span b efore urinary retention involvem ent. • C hronic Cauda Equina Syndrom e The patient is usually m iddle-aged or older, w ith no specific history o f injury. In the stenotic patient there is a gradual onset of sym ptom s over m onths or years due to the slo w ly d im inishing volu m e o f the sp i­ nal canal. These are: * urinary incontinence, hesitancy or urgency * sciatica and backache for m any years * pseudo-claudication * perianal o r perineal pain associated w ith neurogenic bow el or b lad d er , dysfunction PHYSICAL FINDINGS • A cute CES A lw ays includes: * num bness in d istribution o f sacral roots ie sole o f feet, buttocks, per­ ineum , scrotum , labia, clitoris. M ay include: * various degrees o f dim inished sen­ sation in the legs and feet (depend­ ing on) level o f obstruction * absence o f the anal reflex and bu lb o ­ cavernous reflex * w eakness of low er extrem ities * severe bladder paralysis w ithout leg pain sym ptom s * unilateral leg signs * blad d er distention * altered low er extrem ity reflexes and m uscle strength * bilateral positive SLR test • C h ronic C E S (m ore subtle) * rectal tone m ay b e dim inished * sensation m ay be altered in the per­ ineum (less than in the acute CES) * low er extrem ity neurological find ­ ings m ay be presen t only w ith p ro­ vocative testing such as w alking and spinal extension INVESTIGATIONS • A cute CES * w ater soluble m yelogram (to deter­ m ine level and extent) * post m yelogram CT * M RI provides sam e inform ation as m yelography * urod ynam ic stu d ies - for prognosis • C hronic CES * thorough n eurologic w orkup * com plete n eurologic assessm ent * m yelogram w ith post-m yelographic CT * urologic assessm ent - intravenous pyelogram * e le c tro -d ia g n o s tic s p h in cte r fu n c­ tion * urodynam ic testing * tests o f renal function SURG IC AL T R EA TM EN T D ecom pression is' indicated w h en the n eu ral e le m e n ts are in v o lv ed cen trally and /or laterally b ecau se long term com ­ p ressive factors are inju rious to the neural elem ents.4 Surgical d ecom pression takes the fo rm o f a w id e lam in ectom y for the canal elem ents o f the cau d a equ ina, and foram inotom y for the lateral nerv e root d ecom pression, or a com bin ation o f these. • In the acu te syndrom e: T he nerve roots are severely traum a- tised b y the com pression and the surgical proced u re is considered to be urgent. Even after decom pression, the end re­ sult o f acu te cauda equ ina episodes show th at the p a tie n t s e ld o m re c o v e rs co m ­ pletely. R e sid u al b la d d e r d y s fu n ctio n is the rule, w h atever the tim ing o f surgical d e­ com pression. W h en rectal and anal d y s­ fu nction occurs the patient m u st, as w ith b lad d er dysfunction, learn to adjust. If saddle anaesthesia p ersists follow ing decom pression, then pelvic v isceral fu n c­ tion w ill rem ain severely disturbed. B ilateral sciatica is also consid ered to have a poor long term prognosis. • In the chro n ic synd rom e: T he surgical proced u re is the d ecom ­ pression o f b o th central and lateral canals at the appropriate level or levels. R esu lts o f ch ro nic cau da equ ina ep i­ sodes norm ally show a slow recov ery over approxim ately a year. It is u su ally in co m ­ plete but has a greater p o tential for the reversibility o f the signs and sym ptom s than the acu te synd rom e. PH YSIOTHERAPY AFTER D ECOM PRESSION A im : M ob ilisation of the n euro-m u scu - lar-skeletal system .. W h e n the c o m p re ss iv e fa c to rs an d , R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) therefore, the p rim ary cau sative factors have b een rem oved /red uced surgically, p hysiotherapy aim s at relieving the seco n ­ dary com pen satory sy m ptom s o f pain and lim itation o f m ovem ent throughout the neuro-m u scular-skeletal system s. Respecting the d eg ree o f recovery, and using the resu ltant n eurological m anifes­ tations as a y a rd s tic k , the g e n era l ap­ proach b y m anual therapy is the sequence of passively * m obilising intervertebral jo in ts * releasing soft tissue stru ctures * stretching neural tissue. Physiotherapy aim s to treat pain first to prepare these stru ctures for the phase of actively m aintaining w h at has b een p as­ sively achieved. CASE PR ESEN TATIO N 1 • A cu te C aud a E quina Synd rom e (Disc H erniation) Forty-year-old m ale w ith p ast history (8 years) o f chronic b ack pain and sciatica, probably due to years o f ru gby and aggra­ vated by y ears o f d rivin g (sales rep re­ sentative). N o specific injury. First co n su ltatio n w ith d octor w as 3 years ago - m ajor com plaints constan t se­ vere low back pain and sciatica o n the right. H e w as hospitalised for 3 days on a program m e of: * bed rest * sym ptom atic relief using spinal m o­ bilisation techniques * m edication. He reported a m arked im provem en t and w ith the assistance o f a fu nctional co r­ s e t w h en d riv in g , an d o ra l a n a lg e sics w h en required, he kept going. O ne year ago, as he bent forw ard and twisted to the right to pick up a light object, he coughed. H e experienced severe lanci­ nating pain in his b ack, follow ed im m edi­ ately b y severe rad iating pain and w eak­ ness in b oth low er extrem ities, and bladder retention. H e w as ad m itted to h ospital im m edi­ ately and w ith in an hou r a m y elo g ram w as p erfo rm ed . The m y e lo g ram revealed a com plete block at the L4-5 level. Surgery w as perform ed 3 hours later w ith rem oval o f an enorm ou s fragm ent of disc m aterial lying free w ith in the spinal canal, and som e p artially extruded disc fragm ents from the interspace. Post-opera- tively, there w as sig n ifican t im provem en t in low back pain and sciatic pain, b u t the m otor w eakness o f the right low er extrem ­ ity p ersisted , n e ce ssita tin g a fo o t d rop brace. H e required a Foley catheter for 5 m onths after w h ich he continued to have u rin ary sp h in cte r and p e rsiste n t rectal sphincter im pairm ent. For the blad d er and b ow el dysfunction, he w as taught the long term m anagem ent. D espite everything, he returned to his w ork one m onth p o st-op ­ era tively. This case suggests that a severe and m assive retropulsion o f an intervertebral disc w ill probably traum atise the nerve roots so severely, or produce such perm a­ nent changes to the vascu lar supply of the cauda equina, that a serious residual effect w ill persist no m atter how prom ptly the pressure is surgically relieved. CASE PRESENTATION 2 • Chronic Cauda Equina Syndrom e (Spi­ nal stenosis) O bese 56 year old hou sew ife w h o fell onto her buttocks 2 years ago. She could get up but the follow ing day developed severe back pain. This eased w ithin a few days w ith bed rest, p hysiotherapy and an­ algesics. She experienced interm ittent low back pain over the follow ing 8 m onths and d e­ veloped a nu m bness from the w aist dow n in a s s o cia tio n w ith re cta l and u rin ary sphincter im pairm ent. A m yelogram re­ vealed a com plete block at L5-S1 w ith a sm aller m id-line defect at L4-L5, for w hich surgery w as recom m ended. She declined, continued w ith physio­ therapy, and the assistance o f a functional corset and m edication as required. N ine m onths later she developed uri­ nary incontinence and w eakness o f both low er extrem ities. She struggled on for an­ other 4 m onths w h en she could avail h er­ self for surgery. Exam ination * loss o f m obility of lum bar spine, par­ ticularly in flexion * severe lu m b ar p ara-sp in al m uscle spasm * saddle anaesthesia w ith num bness extending into both legs * SLR L=R-60° * both TA reflexes absent * anocutaneous reflex absent bilat­ erally. Surgery * d e c o m p r e s s i o n l a m in e c t o m y L4,5,S1 * bilateral foram inotom y at L5-S1. A Y ear Post-operatively * original severe pain in low back and both extrem ities had gone * num bness and w eakness in both legs had com pletely gone * urinary incontinence im proved - continued to experience urinary frequency . * slight hypaesthesia to pinprick over sacru m and p e rin eu m and m otor strength o f b oth feet alm ost norm al - fatigues * SLR L=R=80°. This patient p robably had a less acutely d eveloping lesion w h ich produced com ­ p aratively less traum a to the cauda equina and provided greater p o tential fo r revers­ ibility. D espite the delay in treatm ent, she had a satisfactory result. DISCUSSION C ase history 1 - d em onstrates the clas­ sic p re sen ta tio n o f a G ro u p II A C U TE cauda equina synd rom e ie the sudden o n ­ set o f a m assive disc h erniatio n at L4/5 w ith im m e d ia te b la d d e r in v o lv e m e n t. Even after im m ediate decom pression, he had serious resid ual dysfunction. Case history 2 - is the classic presen ta­ tion o f a chronic cauda equina syndrom e. P o s t-d e c o m p r e s s io n re c o v e ry ov er ap­ proxim ately a year left her virtu ally pain free, w ith slight neural deficit, and fu nc­ tional. C ONCLUSION C au d a Equina Sy nd rom e presents as an acu te o r chronic com p ressive lum bar syn­ drom e. It is a serious cond ition alw ays involving the b lad d er and resulting in sur­ gery. M o st patients end up w ith a residual dysfunction and p hy siotherap y is essen­ tial to gain the m axim u m recov ery avail­ able to the n euro-m u scular-skeletal sys­ tem. R eferences: 1. Mcneill T W. Lumbar Spinal Stenosis, Mosby Year Book, ed Anderson G B J, Mcneill T W, 1991:16. 2. F lom an Y, W iesel S W , R o thm an RH. Cauda equina syndrome presenting as a herniated lumbar disc. Clin Orthop 1980;147:234-237. 3. Tandon P N, Sankaram B. Cauda equina syn­ drome due to lum bar disc prolapse. Indian J Orthop 1967;1:112-119. 4. Richard J. Surgical Management of Lumbar spinal stenosis 1986. Spine 1987;12(8):809- 816. F e b r u a rie 1995 B la d s y 12 S A T y d s k R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. )