Acta Neurochir (2005) [Suppl] 92: 107–109 6 Springer-Verlag 2005
Printed in Austria
Surgical intradiscal decompression without annulotomy in lumbar disc herniation using a coblation device: preliminary results
A. P. Fabrizi and M. Zucchelli
Department of Neurosurgery, Bellaria Hospital, Bologna, Italy
Summary
Annulotomy is a mandatory step to perform intradiscal decom- pression to resolve a disco radicular conflict. However, this ma- noeuvre can lead to post surgical complications such as vertebral instability and back pain.
Coblation assisted microdiscectomy (CAM procedure) allows a quoted removal of disc without anulus damage.
Keywords: Coblation; lumbar disc herniation; annulotomy; verte- bral instability; postsurgical back pain.
Introduction
In the last years with modern microdiscectomy techniques surgeons have reached many important goals in spine surgery: the incidence of intraoperative bleeding is now very low, time of hospitalization is short, the postoperative pain is low and the radicular symptoms are eliminated in a very high percentage of patients.
However, today we still have a 10% recurrence and postoperative back pain in 40% of cases.
The cause of recurrence can be sought in a loss of tension of the disc, that is even more weakened by the surgical annulotomy preceding microdiscectomy.
Postsurgical back pain can be caused by an excessive removal of disc contributing to the basis of vertebral instability and its first consequence: back pain.
The CAM procedure allows the surgeon to perform microdiscectomy without annulotomy with a defined amount of disc tissue removed.
Coblation technology removes tissue by using low- energy radiofrequency wave to create an ionic plasma field from sodium atoms within the nucleus. This low- temperature plasma converts tissue into gases by a molecular dissociation. Coblation is not temperature-
driven and does not rely on heat energy to remove tissue. Thus thermal damage and tissue necrosis can be avoided.
Materials and methods
The coblation device which uses plasma energy to remove tissue and to create small channels within the disc, is of a bi-polar design allowing a fully contained plasma field at the tip to provide highly targeted tissue removal without injury to the surrounding tissue. For coagulation the device uses higher energy to create heat in the tissue (Figs. 1a and 1b).
The surgical steps for the CAM procedure are the same as for the classic microdiscectomy up to the intervertebral disc (the patient is under general anaesthesia, in genupectoral position). Thereafter we do not perform the annulotomy but a 17-gauge needle is inserted under direct control into the annulus (Fig. 2). Through this mi- crosurgical approach the electrode is introduced which removes a defined amount of intradiscal tissue at each passage and in every planned direction determined by the surgeon.
Through this procedure a decompression inside the disc is achieved without damaging the integrity of the annulus. The extent of decompression can be verified by direct inspection or with pal- pation instruments.
After extraction of the needle we perform a classical closure layer by layer.
The inclusion criteria for patients were – Leg pain greater than back pain
– MRI evidence of contained posterior-lateral disc protrusion – Failed conservative therapy for at least 3 months
The exclusion criteria were – Disc Height less than 50%
– Evidence of severe disc degeneration – Spinal fracture or tumor
– Moderate/severe spinal stenosis
In the period August 2003 to September 2003, 6 patients underwent the CAM procedure. In 4 cases the herniated disc was at L4/L5, in 2
at L5/S1. In 4 cases the herniation was left, in 2 right. One patient had a previous microdiscectomy at the same side and at the same level. We did not use topic steroids in any patient.
The referred symptoms were back pain with sciatic pain in 3 cases, 3 patients had only radicular symptoms.
Only one patient presented weakness in the tibialis anterior muscle.
All patients were discharged on the third day with orthopaedic corset.
Results
During the surgical procedure we achieved in all cases an important intradiscal decompression, aimed at disappearance of the radicular conflict. The annu-
lus, after pulling out the needle, was macroscopically intact.
The immediate results (at discharge) were excellent:
the pain had disappeared in all cases from the day of surgery.
The short term follow-up and the small number of treated cases does not allow quantification of recur- rence frequency but we think the intradiscal decom- pression obtained and the annulus preservation are important to improve results and to minimize post surgical complications.
Conclusions
We think that the CAM procedure is a useful tech- nique for intradiscal decompression without damage to the annulus (which would be the base of a low per- centage of recurrence) and a predetermined tissue removal procedure (the basis for a low percentage of vertebral instability). The limited series and the short follow-up period does not permit the authors to pro- vide definitive results. This is left to the future through further studies.
References
1. Chen Y, Lee SH, Chen D (2003) Intradiscal pressure study of disc decompression with nucleoplasty in human cadavers. Spine 28 (7): 661–665
Fig. 1(a–b). Micro DisCoblator (MDC) SpineWand
Fig. 2. Intraoperative needle insertion
108 A. P. Fabrizi and M. Zucchelli
2. Gerszten PC, Welch WC (2002) Alternative strategies for lumbar discectomy: intradiscal electrothermy and nucleoplasty. Neuro- surg Focus 13: 2
3. Preliminary Outcomes of Percutaneous Nucleoplasty (2002) A comparison of patients with versus without an associated central focal protrusion. Eur Spine J 11 (4): 416–417
4. Sanders N, McMahon R, Yetkinler D (2002) Nucleoplasty: a novel approach to percutaneous disc decompression. 6th Inter- national Congress of Spinal Surgery, Ankara Turkey
5. Vives M, Manos R, Yuan P, Kau¤man C, Garfin S, Yetkinler D (2002) The e¤ect of radiofrequency energy on dural tissue: histo- morphologic analysis. Eur Spine J 11 (4): 417
Correspondence: A. P. Fabrizi, Division of Neurosurgery, Bel- laria Hospital, University of Bologna, Via Altura No. 3, 40139 Bologna, Italy. e-mail: [email protected]
Surgical intradiscal decompression without annulotomy in lumbar disc herniation using a coblation device 109
