Neurosurgical attitude to lumbar spine instability after disc operations

Tuesday. 8 July 1997

Spine - Lumbar Disc Herniation and Spondylosis

S165

of intervertebraldisc excision can be preventedby early diagnosis. the correct Three of them weredorsomedialand two weredorsolateral,left-sided hemichoice of treatment. and meticulouscare during surgical intervention. ations. All were operatedand showedgood recovery(threeby interlaminectomy interarcuarisand two by left-sidedinterlaminectomy).

IP-4-424 ! Recurrentlumbardischerniations: A review of 182 operated cases N. $i~li , H. Toplarnaoqlu, R. Atabey, B. Bozyigit. B. Gunduz, N. Kazan. Bakirl<6yPsychiatricand NeurologicalDisease Hospital Neurosurgery , Department, Istanbul, Turkey

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BAK·method of lumbarinterbodyfusionin chronic low back pain

G. Matge. NeurosurgicalDepartment, GentreHospitalier,Luxembourg

The degeneratingdisc seems to be the primarysource of low back pain (LBP). Among 4820 casesoperated for lumbar disc herniation in two different cenLBP. also they had a 10 to 15% of these patients becomechronic with disabling ters between 1986-1996 182 patients who had the previous discectomyan minimumof 6 monthsseriousmedicaland physicaltherapy. After thorough clinaverage 3 years and 6 month were treated for recurrent disc herniation by ical andradiologicalexamination, these patients may be considered for spinal repeallaminectomyanddiscectomy.The purposeof this study was to evaluate fusion.Principalindicationsfor BAK-fusionare degenerativediscopathy at one which patients should be included in the re-operationprotocol and with which or two levels. some casesafter failed back surgery. and grade one spondylolisindications . The authors discuss several problem related to this condition. 100thesis.Infection,osteopenia,malignancyand traumaticinstabilityare excluded. stabilizationwith bilateralthreaded cylindrical titanium patients were operated previously in the same centers but 82 patients in theDistraclion-eompression other centers. There were 91 men and 91 women (with mean age of 40.7). The cages andautogenousbone graft has been proofed efficientbiomechanical in operationwasperformedthrough an interlaminarapproachwithout microscopic and animalstudies.Stable fusion has been achieved in a large FDA approval approachis retained in thispresentation,a wide magnification.Residualor re-extrudeddischerniation.scartissues,arachnoidistudy, Only the open posterior tis were found atoperation.The series were divided accordingto pre-operative enough laminotomyand facetectomywith power drill. Special instrumentation findings into five groups. Group I: 78 patients with protrusionat the same side with safety anchored tubes. distractors and drills allows screwing the implant centers.Group and same level (truerecurrence).37 patients operated in same (13 or 15 mm cages) in the prepared bone bed. Emphasis will be made on II: 39 patients with protrusionat a different level and same and/or controlateral. distraction(foraminal opening) andsymmetricalendplate drilling assisted by controlateralside. X-raycontrol.Surgicalbone site graft obviatesautograftand allograft complicaGroup III: 11 patients with protrusion at the same level but preserved.Additional fixation is not indicated with this Group IV: 50 patients with only scar tissue and Group V: 4 patients with arach-tions. Natural lordosis is noiditis.Herniationsat other leveland true recurrencesof lumbardisc hemiation autostabilizingdevice. Clinical results for pain and function are good. Fusion rate is high and improves overtime. Technical problems and complications are showed the best results (excellent in 96% and 60.2% respectively)than scar discussed.as well as indications, advantages to alternative procedures and formations which had less satisfactory(only 40% excellent results).Differences BAK-system. between clinical aspects and imaging studies unique to either scar tissue orcautionsconcemingthe recurrent disc hemiation should be distinguishedto avoid a secondoperation. MRI proved more reliable in distinguishing between disc prolapse and fibrosis than CT andmyelography . Therefore MRI is the diagnosticmethodof choice in P-4-42S I Neuro~urgical a~itude to lumbar spineinstability after diSC operations theseconditions.

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IP-4-425 I Microsurgical operationson lumbar discherniations after percutaneouslaser-disc-decompression

V. Srnrcka, Z. Novak, O.Baudysove. Neurosurgical Departments Brno-8ohunice and rBno-Pekafska,Czech Rep

In a group of 1242 patients operated for hemiated disc in the neurosurgical department of Bmo we have noted 84 patients ( l%) who came back with lumbar pain due to instability of the lumbar spine. The diagnosis was made M. Zell, M. Scholz.A.G. Harders.NeurosurgicalDepartment.Universityof from the clinicalsigns, functionalX-rays with loading and a CT scan. Long-term Bochum, Germany resultsare availablein 38 patients. Introduction:Percutaneouslaserdiscdecompression (PLOD) isrecommended A clowardoperationmodifiedfor the posteriorapproach to the lumbar spine intervertebralspace was always was performedin all of these patients. The since 1987 for treatment of lumbar (and cervical) disc herniations. The method evacuated together with the covering plates of the vertebral bodies and filled and indications are described as known from the literature.Our study should withautologousbone grafts from the iliac crest or from the spinal process. evaluatethe effects and the complicationsof thismethod. Method: Aprospectivestudy of 20 patients has been carried out. All were The patients had to wear a lumbar brace for 3 months. Ossificationof the two adjacentsegments was usually present on the follow-up X-ray one year after operatedmicrosurgicallyon lumbar discherniationsafter PLODhad been performedin aassociateddepartment.12 female. 8 male.They weretreatedin our theoperation.Clinicalimprovementwas observedin 24 patients(63%) who had departmentduring the last 30 months. Mean age was 43 years (range 30-53). no orsignificantlydecreased lumbar pain after the operation.In the rest of the temporaryor no effect. patientsthere was only Average duration of symptoms (sciatic pain) was 6.7 months. Hypaesthesiain We think that this method is beneficial and should be considered in the L5/S1 8, paresis in 9 patients. Segments involvedwere 19 times L4/5, 6 times treatmentstrategy.Furtherimprovementmay be achieved by the use of metal and once L3I4. In 7 patients PLDDwas performedin 2segments,3 timestwice. instrumentationin selectedcases. Average time between last PLDD and microdiscectomywas 4 weeks. In 17 patients CT- and MRI-scansshowed sequestrateddischerniations. Results: During theoperationson these patients thesuspected,sequesP-4-429I A morphometricanalysis ofextra-foraminaI lumbar . 1 trated disc herniations were found. 16 patients improvedafteroperation the nerve roots reoperationfor recurrenceand 1 spondylodiscilis occurred. Histopathological pigmentsas Laser findings: four times phlegmonousinfections. nine timesblack Soon-KwanChoi,Hack-GunBae, Bark-JangByun.Department of effect. Neurosurgery,Soon-Chun-HyangUniversity, Seoul, South Korea Discussionand Conclusions:Thesepatientsshould not havebeentreated by PLOD because they suffered from disc herniations that had been alreadyBackground:In the posterolateralextraforaminal or anterolateral retroperitonealapproachfor extremelateral lumbardisc herniation, the neural structures sequestrated. around the lumbarextra-forarnlnal region are unfamiliar to the neurosurgeon. The purposeof this study was to determinethe normal anatomic morphometric parameter of all lumbar nerve roots around their exit from intervertebral the P-4-426 Intradurallumbar discherniation foramento thesurroundingbony structure. I. Radic " B. Bozic' L . . Negovetic' ,A. Kogler1• O. Kovac' , R. Skarica 2. Materials & Methods: A total of 15 adult formalin fixed cadavers were 1 DepartmentofNeurosurgery,UniversityHospital Sisters Mercy, of Zagreb, studied. Theentire lumbarspineoccupiedby psoasmajormusclewas dissected Croatia.2 Department ofsurgery,Division ofNeurosurgery,County General and removed to expose the full course of the lumbar nerve roots and lumbar Hospital,Zadar, Croatia plexus. Theextraforaminallocation of the course of the lumbar nerve roots and Intradurallumbar disc herniation is a rare pathologicalentity. first describedby the plexus wasmeasured segmentallyin the horizontal plane with a standard caliper.Landmarkswere the most medial and superior margin of transverse Dandy in 1942. Itspathogenesishas been a matter ofdiscussionever since process (TP), the most posteriorof intervertebralforamen (IVF), and the most (congenitaladhesionsof the dura mater to the posterior longitudinalligamentat respectively. The angle of inclination of each nerve root the lower lumbar spine; weakness of the dura mater ventrally and at the axillaanterior margin of IVF of the nerve root). measuredwith agoniometer. locatedoutwardsto IVF was About sixty cases have been described in the literature.At theDepartment Results: The distancefrom superior medial border TP to the lateral border of Neurosurgery,UniversityHospital Sisters of Mercy, Zagreb,4000 cases disc (range, 7-11 mm) in L2 of correspondingnerve root was 9 mm (mean value) protrusionshave beenoperatedover a 9-yearperiod,5 of which were intradural and L3 level, and 6 mm in L4 and L5 level. The distancefrom the most superior discherniations.All of them were located at the l.v, space level L4-L5-S1. border of articular facet joint, namely, the most posterior border of IVF to the

(PLOD)

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