Spine Clinic Neurospine Specialists, Orthopaedics and Neurosurgery

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1 Spine Clinic Neurospine Specialists, Orthopaedics and Neurosurgery REVISION SPINE SURGERY Revision surgery is a very complex field which requires experience, training and evaluation in a very individual basis to understand what are the causes of an unsuccessful result. The surgical team must take in consideration that the normal spinal anatomy, biomechanics and biology are pathologically altered. The structures of the spine may be more difficult to reach through a standard or similar to the first operation approach. Nerves and vessels may be very difficult to approach, release and mobilise. Scar tissue from the previous surgeries makes the procedure quite challenging. The causes of revision spine surgery are many times multifactorial Re-herniation of a disc after microdiscectomy: is basically a repeat of the symptoms (sciatica) that led to surgery at the first time. Repeat the discectomy is a reasonable approach if the intervertebral disc is still functional and there is no back pain and/or instability. In case of biomeccanical insufficiency of the reherniated disk a more drastical solution is required. Most likely a complete removal of the disk and a fusion will be required. Pseudarthrosis (failure to achieve fusion by 6 months to 1 year after surgery): may be the result of poor tissue healing (biological factors play a very important role), smoking and/or use of corticosteroid and antiiflamatory (NSAID) medications. The type of bone graft used, the hardware installed and the surgical techniques used play a very important role for the outcome of any operation. Post operative instability: secondary to the removal of important spine stabilising structures as spinal apophyses, facette joints, interspinous ligaments and great portions of intervertebral disks. Inadequate muscle reconstruction after open surgeries, stabilisation through inadequate implants are major causes of instability. Adjacent segment disease: anatomical changes of the spine can occur at spinal joints above and/or below the area of a spine surgery (this is true mostly for the cervical spine and less documented for the lumbar spine). This generally occurs after 1-3 pain-free years. Most of the times is the result of residual postoperative instability combined with kyphosis of the treated spinal segment. Alteration of the normal sagital profile of the spine: Even after an apparently successful surgery with significant relief of pain and fatigue, the shape of the spine can deteriorate and require further surgery (for example: segmental kyphosis/scoliosis, flat back syndrome, vertebral fractures due to osteoporosis etc). This is particularly true is the primary surgery did not restore or even worse produced a kyphotic deformity. Infection: any kind of surgery can be complicated from a microbial contamination. This complication is very rare in our days because of the very careful sterilisation methods, evolution of the surgical techniques, biocompatibility of the implants and climatisation of the operation theatres.

2 σελ. 2 Imaging and diagnosis X-Rays in standing position: are always the first imaging method to be used. Normally is the best method to investigate on the shape of the spine (sagital profile, scoliosis) and the relation between the bony structures after an operation. As a protocol, normal x-rays are performed 3, 6, 12 months after an operation in order to control the healing process. It is the examination where an eventual postoperative problem will be recognised. They must always be performed but many times are forgotten as old fashioned related to the MRI or CT, which are complementary. Dynamic x-rays of the spine: are a very good method to reveal instability. Many times are performed in combination to a myelography. Myelography and CT myelography: is a very useful examination which combines an intradural injection of special radiopaque contrast with dynamic x-rays of the spine in various positions. The shape and the diameter of the spinal canal can be perfectly visualised and compared in flexion, extension and different inclinations of the spine. An additional Computer Tomography (CT scan) improves the visualisation in difficult cases. Magnetic Resonance Imaging (MRI) with T1, T2, STIR sequences: is the method of choice when it comes to control of the soft tissues and of the biological reaction of any tissue of our body. A contrast agent (gadolinium) may be helpful to distinguish scar from normal tissue. It is extremely useful in localising the scar tissue, re-herniations, bone oedema in vertebral fractures making it possible to distinguish between healed and fresh lesions. The hydration of the intervertebral discs as a degeneration index is easily shown from this examination. It is performed in a laying position and this is one of the major disadvantages of the method as it may not show alterations which depend from the standing position of the patient. Bone scanning: is a biologic method in which a radionuclide given intravenously is fixed in areas where a pathologic process is occurring. Is an extremely sensible method but has a very low specificity. It is very useful in tumour cases, infections and fractures of the vertebral bodies. Many times is used in patients with implanted pacemakers, stents or other implants incompatible with an MRI. Surgical treatment Revision surgery for a failed disc herniation may require fusion (if lumbar pain and instability occurred) or may require microdiscectomy again if the intervertebral disc is still functional. The use of new techniques (for example Barricaid implant) during the original or second surgery can reduce significantly the rates of recurrence. Revision surgery for a failed spinal fusion or for post operative instability requires always a circumferential (360 o ) fusion and therefore exposure of the front and/or lateral and back of the spine. The biggest mistake

3 σελ. 3 among spine surgeons is to apply only posterior fixation and fusion (normally with grater diameter screws) which very frequently lead to new and more complicated failed back surgery. Anterior and lateral approaches (ALIF and XLIF techniques) and the use of intervertebral cages is indispensable in these cases, in order to restore the normal spinal alignment, improve the load sharing between anterior and posterior part of the spinal column and stabilise the spine in its correct balance. The choice of the bone graft to be used is also an important factor of success. We prefer the use of autograft and/or allograft mixed with growth factors (appropriately centrifuged - celling technologies) to achieve the best result. The previous instrumentation is usually removed, the spine then may be released (through osteotomy) and or/realigned and fused in proper sagital profile using new instrumentation. Revision surgery for changes above or below a previous successful fusion usually requires extension of the instrumentation and fusion. Revision surgery for infection requires irrigation and debridement of the infected tissue, local use of autograft mixed with local antibiotics, solid stabilisation with proper implants and targeted intravenous antibiotic treatment. Success rate The success rate of revision spine surgery depends on correct the diagnosis and uncompromised surgical indication. In some instances repeat surgery for the same problem may not be as successful as an original operation, which can make revision surgery more challenging. The surgical team of the Spine Clinic of the American Medical Center (head of department: Dr Petros Stavros) consists of Orthopaedics and Neurosurgeons specialised in Minimally Invasive, Complex Spine Surgery and in Revision Spine Surgery. The surgical team working together knows how to prevent problems during the first surgery as well as approach with very high success rates patients that have been already operated many times. The success rate of revision lumbar spine surgery in our hands overpass the 85%, even in the most difficult cases. Successful outcomes are significantly associated with the spinal approach and the successful fusion process. Patients with defined mechanical instability and with stenosis have the best results.

4 σελ. 4 Below are a few cases of lumbar revision cases performed from the surgical team of Neuro-Spine Specialists, Orthopaedics and Neurosurgery of the American Medical Center. Case 1 Woman, 45 y. old, with history of multiple discectomies L5/S1, with reprolaps and persisting sciatica (VAS = 7-8/10) and post op instability + adjacent segment degeneration L4/L5. We performed an anterior fusion through an anterior retroperitoneal approach and L5/S1 360 degrees fusion and dynamic posterior stabilisation L4/L5. Total time of surgery was 2,5 hours, with minimal blood loss and with 2 days of hospitalisation. Two months after surgery she has no leg pain (VAS = 2/10) and she is back to normal activities with some precautions due to the early postoperative period.

5 σελ. 5 Case 2 Adult, 42 y. old, with extreme lumbar pain due to pseudarthrosis after a stand alone PLIF operation at the L3/ L4 level about 1 year before. We performed a lateral transpsoas L4/L5 approach, removal of the previous cages, preparation of the disc space and implantation of a lateral interbody cage (XLIF technique) with allograft and growth factors through centrifugation of autologous bone marrow blood. The stabilisation was completed with bilateral transpedicular screw fixation. Total time of surgery was about 2 hours, with less than 30cc blood loss and a total time of hospitalisation of 48 hours. Three months after surgery the fusion was achieved and the patient was free of pain and turned back to his normal activities.

6 σελ. 6 Case 3 Woman, 57 years old, with back pain, neurogenic claudication after six (6) unsuccessful lower lumbar operations (VAS pre op = 8/10, very lo Oswestry score). She has first a discectomy L4/L5, then a fusion L3/L4 and L4/L5 in TLIF technique, then a new posterior instrumentation because of pseudarthrosis in both L3/L4 and L4/L5 levels, then two debridement posterior operations because of infection and at the end a removal of the posterior instrumentation for the same reason. The lumbar spine was unstable and collapsed. She could hardly walk for meters. We performed a combined lateral and posterior approach and a 360 degrees fusion at the L4/L5, L3/L4 and L2/L3 levels a pedicle subtraction osteotomy in order to improve the sagital profile and posterior transpedicular fixation from T11 to L5 in order to restore the normal curves of the spine and stabilise the lower lumbar spine in the proper position. The patient 6 months after surgery was very satisfied (VAS =2-3/10) and she was almost back to her normal activities. One year after the operation she has a very normal appearance and she was happy with the result.

7 σελ. 7 Case 4 Woman, 59 y old, with pseudarthrosis L3/L4, adjacent segment degeneration L2/L3, osteoporosis and instability L5/S1 after multiple previous operations in her lower lumbar spine (VAS Pre op = 7/10). She was taking opioid pain killers in very large doses for more than one year. We removed the previous posterior instrumentation and through a lateral approach performed a new interbody stabilisation of the L3/L4 level (XLIF technique). Then through a posterior transforaminal approach performed discectomy and interbody stabilisation of the L5/S1 and L2/L3 levels. The 360 degrees fusion was completed by a posterior transpedicular fixation from L1 to S1 plus iliac screw fixation and vertebroplasty at the D12 level. Total time of surgery was 6 hours. She was mobilised within 24 hours. The total hospitalisation was 5 days. The patient 4 months after surgery is completely independent and she is taking only paracetamol 3-4 times/week.

8 σελ. 8 Case 5 Woman, 43 y. old, with pseudarthrosis, axial cervical pain and severe instability C5/C6 after three cervical operations. A very uncommon anterior resection of the vertebral bodies was performed from the previous surgeon and a partial PMMA interbody reconstruction was performed. The patient had severe instability of the middle cervical spine and extreme tension of the posterior muscles of the neck. She was unable to hold her head in the upright position for longer than 20 minutes. We performed a corpectomy of C5 and C6 and anterior cervical stabilisation with a tantalum corpectomy cage. The operations lasted 2 hours and the patient was discharged 2 days after surgery. Two months after surgery is in excellent clinical condition. Dr. Petros Stavros Orthopaedic Spine Surgeon Dr. Manolis Petridis Neurosurgeon Dr. Panayiotis Pachniotis Neurosurgeon