J. Heine

Degenerative lumbar spinal stenosis. Long-term results after undercutting decompression compared with decompressive laminectomy alone or with instrumented fusion.

Abstract The aim of the study was to evaluate the long-term outcome of various surgical procedures for lumbar spinal stenosis. Operations were performed on 117 consecutive patients for lumbar spinal stenosis between 1987 and 1992. Pre- and intraoperative data were recorded in a standardized manner. Three treatment groups were distinguished: group I consisting of 39 patients submitted to undercutting decompression; group II, 51 patients, submitted to laminectomy and foraminal decompression alone; and group III, 27 patients, who underwent foraminal decompression and laminectomy with instrumented fusion. Eight years (5–10 years) after surgery a questionnaire was mailed to the patients containing the outcome scales according to Greenough and Fraser [6] and Turner et al. [22] together with questions about residual pain, necessity of treatment and satisfaction with the operative outcome. A total of 72 questionnaires (61.6%) gave enough information for analysis. After a mean follow-up of 8 years, walking capacity had increased significantly in all groups (P<0.001). Compared to preoperative values, pain had decreased significantly in all groups (P<0.01). In group I 36% had good-to-excellent outcomes, and 30.8% and 23.8% in groups II and III (P>0.05). Forty percent of group I patients were unsatisfied with the result, compared to 38.4% and 33.3% in the other groups (P>0.05). Overall, 25 of 72 patients (34.7%) had severe constant back and/or leg pain requiring daily administration of analgesics. We conclude that the long-term outcome of decompressive surgery of the lumbar spinal canal, without and with instrumented fusion, is less favourable than was previously reported.

Decompression/stabilization of the metastatic spine. Cotrel-Dubousset-Instrumentation in 50 patients.

50 patients with metastatic disease of the spine underwent dorsal decompression and stabilization with the Cotrel-Dubousset-Instrumentation from 1987 to 1991. Indications for surgical treatment were neurologic deficit, spinal instability, and/or pain resistant to medical or radiation treatment. No external orthotics were used postoperatively. Pain was relieved dramatically in 45 patients. Among 25 patients suffering from neurologic deficit preoperatively, 13 improved, 15 remained unchanged, whereas 2 developed an incomplete, transient paraplegia. 15 (7) patients were alive after 1 (2) years. Postoperative complications were frequent, but there were only 2 failures of the stabilization device requiring reoperation.

Sagittal static imbalance in myelomeningocele patients: improvement in sitting ability by partial and total gibbus resection.

Abstract The progression of kyphosis in myelomeningocele is independent of skeletal growth and requires early operative correction and stabilization to prevent a loss of sitting ability. In severe cases, only vertebrectomy makes it possible to achieve correction, stability and skin-closure without tension. In 14 patients with myelomeningocele gibbus, kyphectomy was performed, removing two vertebral bodies on average. The average kyphosis angle decreased from 128° to 81°, enabling most of the patients to participate again in social life by restoring wheelchair mobility. Nevertheless, a significantly higher complication rate was found compared to other correctional operations, lengthening the average hospital stay to 41 days. Special problems arose from trophic disorders of the skin and soft tissue and from the dystrophic muscles below the level of neural malfunction. In three cases, kyphosis reappeared cranial to the fused segments, requiring ventral stabilization. With respect to increasing kyphosis angle, an early intervention should be aimed at. A secondary operation can be necessary, if surgery is performed without taking care of the growth potential.

Metastatic instability at the proximal end of the femur

A retrospective study was performed of the surgical treatment of metastatic lesions of the proximal femur in 50 patients. In 25 consecutive cases a megaprosthesis was implanted; compound plate osteosynthesis was performed in another 25 consecutive patients. Indications for surgical treatment were pathological fractures or, for prophylactic treatment, lesions of the femoral cortex exceeding 2.5 cm in diameter or affecting half the diameter of the bone or more. In all patients capable of walking preoperatively mobility was regained. Immediate full weight-bearing stability was obtained in all patients. Group analysis showed that the functional rating of the hip joint was unchanged, i.e., good or excellent, in all patients with compound osteosynthesis, compared to only 68% in the endoprosthesis group. Pain relief was excellent or good in 84% and 88% respectively. Dislocation of the tumor prosthesis occurred in 3 patients. Closed reduction was possible in 2 cases. Local recurrence was higher in the patients undergoing plate osteosynthesis, as was the frequency of tumor-related implant failure. Postoperative survival averaged 14.7 months and 12.1 months respectively.

Prognostic criteria for work resumption after standard lumbar discectomy

Abstract The purpose of this study was to determine prognostic criteria for return to work 9–12 years after standard nucleotomy for herniated nucleus pulposus confirmed by CT. From 1985 until 1988, 182 patients (102 male, 80 female, mean age 45 years) with a single-level herniated nucleus pulposus were operated on for the first time. In summer 1997, an average of 10.2 years after the operation, 101 of 182 patients (55.5%) returned a standardised questionnaire. Eighteen patients (9.8%) had died during the intervening years, while 63 patients (34.6%) were lost to follow-up because of moving to other cities. Two groups could then be distinguished: group I worked full time in their usual job; group II did not. The influence of the degree of the paresis, time elapsed since the occurrence, intraoperative findings, age, sex, weight, type of work and re-operations were analysed statistically. Group I consisted of 44 patients who still worked full time in their usual job. Group II contained 57 patients, of whom 18 worked only part of the time, 9 had changed to a lighter full-time job, 23 had taken early retirement, and 7 were receiving a pension. Patients in group I were significantly younger (38 vs 51 years), had a smaller proportion of patients with more than 20% overweight (27% vs 44%), had a smaller proportion of severe, grade 0 and 1, motor dysfunction (0% vs 16.3%), had been operated sooner (within 3 days: 52.3% vs 19.3%), had undergone fewer re-operations for recurrence of the herniation (4.5% vs 21.1%), and had worked less frequently in physically demanding jobs (6.7% vs 22.8%). We concluded that when there is a relative indication for herniated nucleus pulposus surgery, it should be limited to patients aged below 40 years, with slight motor dysfunction, who work in physically undemanding jobs, so as to make a satisfactory long-term result more likely.

Die hochenergetische extrakorporale Stoßwellentherapie (ESWT) bei Pseudarthrose

ZusammenfassungDie Therapie der Wahl von Pseudarthrosen war bisher die Operation mit Osteosynthese und Spananlagerung. Seit den 90er Jahren wird die extrakorporale Stoöwellentherapie (ESWT) als nichtinvasive und risikoarme Behandlungsmethode bei Pseudarthrosen eingesetzt.Ziel dieser prospektiven Studie war es, den Behandlungseffekt bei einem homogenen Patientengut zu überprüfen und prognostische Faktoren herauszuarbeiten.An einem Patientengut von 43 voroperierten Patienten mit seit 9 Monaten bestehenden Pseudarthrosen wendeten wir die hochenergetische ESWT (0,6 mJ/mm2) mit 3000 Impulsen (Siemens Osteostar) in einer Sitzung in Regionalanästhesie an. Zuvor wurde zusätzlich eine Skelettszintigraphie zur Differenzierung von aktiven und inaktiven Pseudarthrosen durchgeführt.Nachuntersuchungen erfolgten nach 8 Wochen, danach monatlich bis zum 9. Monat nach ESWT. Nach durchschnittlich 4,0±0,6 Monaten trat bei 31 von 43 (72,1%) Pseudarthrosen ein knöcherner Durchbau auf. In der Mineralisationsphase der Szintigraphie hatten 25 von 31 (80,6%) erfolgreich behandelten Pseudarthrosen eine deutliche Anreicherung gezeigt, gegenüber 4 von 12 (33,3%) der Behandlungsversager. Bei 29 der 35 (82,9%) Patienten mit einer deutlichen Anreicherung in der Mineralisationsphase kam es nach ESWT zu einer knöchernen Konsolidierung im Vergleich zu 2 von 8 (25%) Patienten mit einer negativen Szintigraphie; 6 dieser 8 Patienten rauchten >20 Zigaretten/Tag.Die ESWT bleibt eine klinisch-experimentelle Behandlungsmethode, deren Einsatz jedoch aufgrund fehlender Nebenwirkungen bei Pseudarthrosen gerechtfertigt erscheint. Kontrollierte Studien stehen hierzu noch aus.AbstractThe gold standard for treatment of pseudarthrosis is operation with osteosynthesis and grafting. More than 10 years ago, extracorporeal shock wave therapy (ESWT) was additionally introduced as a noninvasive and low-risk treatment for pseudarthrosis.The aim of our prospective study was to analyze the treatment effect in a homogeneous group of patients and to develop prognostic factors.Forty-three consecutive patients were included in this study. All patients had been operated on for trauma or undergone selective osteotomy and had developed pseudarthrosis that persisted for 9 months. All patients received high-energy ESWT (0.6 mJ/mm2) with 3000 impulses (Siemens Osteostar) in one session under regional anesthesia. To differentiate active from inactive pseudarthrosis, a bone scintigraphy was compulsory.Clinical and radiological follow-ups were done at 4-week intervals starting 8 weeks after ESWT for 9 months. Cortical bridging was found in 31 of 43 (72.1%) pseudarthroses at 4.0±0.6 months after ESWT.Of 31 (80.6%) successfully treated patients, 25 had a positive scintigraphy compared to 4 of 12 (33.3%) treatment failures. Of 35 (82.9%) patients with a positive bone scintigraphy, 29 had bony healing compared to 2 of 8 (25%) patients with a negative bone scintigraphy. Six of these eight patients smoked more than 20 cigarettes a day.ESWT is still a clinically experimental treatment method. The absence of complications justifies its use for pseudarthrosis treatment. Further controlled studies are mandatory.

Dreidimensionale biomechanische Untersuchung eines neuen flexiblen lumbalen Bandscheibenimplantats

ZusammenfassungZiel der vorliegenden Untersuchung ist es, die biomechanischen Eigenschaften eines neuen flexiblen lumbalen Bandscheibenimplantats zu beschreiben. Es wurden 6 Bewegungssegmente L1/2 und L4/5 einer Kalbswirbelsäule mit Hilfe einer dreidimensionalen (3D-)Prüfmaschine untersucht. Die Messungen wurden nichtdestruktiv unter physiologischer Belastung bis maximal 7 Nm vorgenommen. Die Krafteinleitung erfolgte in Flexion/Extension sowie in Seitneigung und Torsion. Es wurden dabei die Translation (in mm) und Rotation (in Grad) jeweils in den 3 Raumachsen gemessen.Zunächst erfolgten die Messung des intakten Bewegungssegments und eine Messung nach einer ausgedehnte Nukleotomie mit durchschnittlich 6 g entfernten Bandscheibengewebe. Anschließend wurde eine Messung nach dem Auffüllen des Zwischenwirbelraums mit einem kaltpolimerisierenden Silikonkautschuk (Polymethylsiloxanepolymer/PMSO) durchgeführt. Es konnte für die Translation und für die Rotation nach Nukleotomie eine signifikante Zunahme (p=0,0313) der Beweglichkeit zum intakten Bewegungssegment gezeigt werden. Nach der Implantation des Kunststoffs konnte keine signifikante Unterschiedlichkeit (p>0,3125) zum intakten Bewegungssegment gezeigt werden. Mithilfe des verwendeten Kunststoffs ist es möglich, die biomechanischen Eigenschaften des intakten Bewegungssegments zu rekonstruieren.AbstractThe aim of this study was to determine the significance of a new artificial nucleus implant for lumbar discs (polymethyl siloxane polymer, DR-PMSO) with special regard to the biomechanical properties of the spinal motion segment.The lumbar segments L1/L2 and L4/L5 were harvested from six calf cadavers. The segments were fixed on a special device mounted on a three-dimensional testing machine. Physiological load with a maximum of 7 Nm was applied in flexion/extension, right and left lateral bending, and right and left torsion.The movement of the measuring point (center of L1 and L4) was registered along three axes (sagittal, frontal, and vertical). Three cycles of measurements were performed on all specimens: (1) intact segment, (2) segment after nucleotomy, and (3) segment with PMSO. There was a statistically significant (p=0.0313) increase in segmental mobility in all directions after nucleotomy with an increased mobility of the segment up to 30% for rotation and 50% for translation. After introduction of the PMSO implant, segmental mobility for all movement directions was restored with no statistically significant difference from the intact situation before nucleotomy. The disc material was found to be noncytotoxic according to current ISO 10993 standards.

Operative management of epidural tumors of the spine

Seventy-two patients with neoplastic involvement of the vertebral column were operated on between 1986 and 1991. In the course of 79 operations anterior decompression and stabilization alone were performed in 3 cases, while ventrodorsal spondylodesis was carried out in 10 individuals. The remainder of the patients underwent exclusively dorsal decompression and stabilization, mainly with the Cotrel-Dubousset instrumentation (CDI). No external spinal support was required following posterior fixation by CDI alone or in combination with ventral spondylodesis. Forty patients suffered from neurological deficits preoperatively, 20 of them being unable to walk, in most cases owing to severe vertebral collapse. Neurologic symptoms improved in 18 patients postoperatively. Median postoperative survival time averaged 11.5 months. In palliative surgery of the spine, posterior decompression and fixation using CDI permit most patients to retain ambulation without requiring external orthotics. The rate of postoperative complications is reduced by the introduction of CDI.

Korrelation degenerativer Bandscheibenveränderungen im MRT mit dem Befund der Diskographie bei Rückenschmerzpatienten

BACKGROUND MRI can be too sensitive for detecting degenerative changes and commonly displays pathology that is not necessarily responsible for the patients symptoms. METHODS Retrospectively, we investigated MRI findings and results of discography in 23 patients with lower back pain. MRI investigations were performed with a 1.0 and 1.5 Tesla device using T1-weighted and T2-weighted sagittal plane imaging and T2-weighted transverse plane imaging. RESULTS Of the 35 degenerated discs, 16 were detected on MRI as having a high intensity zone (HIZ). Eleven of the 35 segments had previous lumbar disc surgery with a HIZ rate of 81.8%, whereas the HIZ rate for unoperated segments was only 29.2%. CONCLUSIONS HIZ is known to be a common lesion found using MRI in lower back pain patients. In operated segments, we found an incidence of 81.8% and in unoperated segments of 28.2%. Discography can discriminate between painful and non-painful discs. With the help of additional parameters such as contrast mean volume and pain characteristics during puncture, the number of false positive discograms can be reduced.

Correlation of degenerative intervertebral disk displacement using MRI with discography findings in patients with back pain

BACKGROUND MRI can be too sensitive for detecting degenerative changes and commonly displays pathology that is not necessarily responsible for the patients symptoms. METHODS Retrospectively, we investigated MRI findings and results of discography in 23 patients with lower back pain. MRI investigations were performed with a 1.0 and 1.5 Tesla device using T1-weighted and T2-weighted sagittal plane imaging and T2-weighted transverse plane imaging. RESULTS Of the 35 degenerated discs, 16 were detected on MRI as having a high intensity zone (HIZ). Eleven of the 35 segments had previous lumbar disc surgery with a HIZ rate of 81.8%, whereas the HIZ rate for unoperated segments was only 29.2%. CONCLUSIONS HIZ is known to be a common lesion found using MRI in lower back pain patients. In operated segments, we found an incidence of 81.8% and in unoperated segments of 28.2%. Discography can discriminate between painful and non-painful discs. With the help of additional parameters such as contrast mean volume and pain characteristics during puncture, the number of false positive discograms can be reduced.