Anterior Endoscopic Cervical Discectomy
Transcription
Anterior Endoscopic Cervical Discectomy
XXVII JORNADA NACIONAL DE ORTOPEDIA Y TRAUMATOLOGIA Acapulco, Mexico May 1-5, 2013 Anterior Endoscopic Cervical Discectomy/Foraminoplasty Surgical Technique with Case Illustration John C Chiu, MD, FRCS (US), DSc Chief, Neurospine Surgery California Spine Institute Thousand Oaks, California, USA President AAMISMS spinecenter.com California Spine Institute Medical Center, Inc “Bienvenida del CSI” Kinh Môi “Ciao” “Bonjour” “Buenos Dias” “Guten Tag!” “Konnichi wa” Calif. Center for Minimally Invasive Spine Surgery spinecenter.com Overview 1. MISS being disruptive technology with dilatation technology instead of cutting technology 2. To discuss endoscopic cervical decompressive discectomy and foraminoplasty 3. Related non-fusion technique and dilatation technology for preservation of spinal motion 4. MISS with limited visualization needs precise MISS approach 5. The importance having MISS technology, education and training needed for meticulous MISS spinecenter.com Endoscopic Anterior Cervical Discectomy (AECD) Demographics of Herniated Cervical Discs (3917) • • Since 1995, 2169 patients with 3917 herniated cervical discs Average age of 43.4 (21 to 82) with symptomatic cervical, single and multiple herniated intervertebral discs • Males: 1109- Females: 1054 • Each failed at least 12 weeks of conservative care • Post operative follow up: 6 to 75 mos. (average 46.4 months) 50 1% 318 8% 44 1% 1039 27% C2 C3 890 23% C4 C5 C6 C7-T1 1576 40% spinecenter.com Surgical Indications: Surgical Indications: • • • • • • • • • • Neck with arm pain (radicular pain) associated with paresthesia, sensory loss, muscle weakness and/or decreased reflexes Intractable cervicogenic headache Discogenic pain At least 12 weeks of failed conservative therapy MRI or CT scan positive for disc herniation Positive EMG considered helpful Positive provocative discogram Multiple discs can be treated at one sitting Post fusion junctional disc herniation syndrome Positive 3 legs of bar stool – symptoms, physical findings, EMG, imaging and provocative discogram spinecenter.com Surgical Indications: In addition, Post Spinal Fusion Junctional Disc Herniation Syndrome (JDHS), Adjacent Segment Disease (ASD) • Two post ACF fusion C4-C6 & C5C6 JDHS cases • MRI showing junctional discs • Anterior endoscopic cervical microdiscectomy (AECD) and foraminoplasty provides relief spinecenter.com AECD Surgical Instruments and Equipment: • Endoscopic surgical instruments for AECD spinecenter.com AECD Surgical Instruments and Equipment: • Advanced endoscopic micro flexible forceps, bone ronguer and navigable dissecting probe spinecenter.com AECD Surgical Instruments and Equipment: • Advanced anterior cervical endoscopic instruments • For bony decompression: – Round ball tip drill – Sharp drill and trephine spinecenter.com AECD Surgical Instruments and Equipment: • Anterior cervical endoscopic instruments Discectomes, working channel sets • • Tri-chip digital camera with cervical 6°endoscope and forceps Holmium YAG laser equipment Laser Thermodiskoplasty (LTD) Endoscopic laser fibers and Instruments spinecenter.com Surgical Procedure/Technique: • Instruments for tissue modulation • Percutaneous MIST interventional procedures: – Injectional, non ablative and ablative tissue modulation technology, laser, RF (radiofrequency), ultrasound, cryogenic and others – MISS surgeons should be familiar with injectional and RF facet denervation procedures and others – MISS surgeons are uniquely suited to perform these for the care of the spinal pain spinecenter.com Surgical Procedure/Technique: Injectional and tissue modulation technology, RF treatment for: – Selective nerve blocks, epidural block and cervical sympathetic nerve block – Facet arthralgia (medial branch of posterior primary rami) – Spinal discogenic pain (related to sinuvertebral nerve) – Cervicogenic headache spinecenter.com ANESTHESIA – AECD Surgical Technique: ANESTHESIA and Intra-operative neurophysiological monitoring (IOM) • Local anesthesia combined with IV conscious sedation with surface EEG monitoring optimize anesthesia and reduce drug requirement • The obvious challenge of MISS is limited visualization and exposure of the relevant anatomy and direct visualization of the nerve • Continuous intra-operative EMG/neurophysiological monitoring in a digital operating room (DOR) prevents undue neural trauma • IOM of neural structure, direct visualization with fluoroscopy and endoscopy creates safer endoscopic MISS procedures spinecenter.com Intraoperative Neurophysiological Monitoring - IOM • Trend of spinal surgery is toward less or minimally invasive spine surgery (MISS) • MISS aims at being less traumatic, with less morbidity and improved surgical outcome • The obvious challenge of MISS is limited visualization and exposure of the relevant anatomy in spite of fluoroscopy and endoscopy to work with, and potentially placing the relevant neural structures at increased risk of trauma • INTRAOPERATIVE NEUROPHYSIOLOGICAL MONITORING (IOM) of neural structure, direct visualization with fluoroscopy and endoscopy creates safer endoscopic MISS procedures • Spontaneous EMG monitoring, at times SSEP and MEP can provide the surgeon with useful feedback to avoid neural trauma during MISS • Intra-operative surface EEG/neurophysiological monitoring optimizes the anesthesia for MISS spinecenter.com Surgical Technique - Step by Step with Case Illustration spinecenter.com Case Illustration I – Large extruded C6-7 disc: 34 year old accountant suffering from intractable increasing neck and left arm pain and weakness. MRI scan showed large C6-7 extruded disc/osteophyte which was relieved by endoscopic cervical discectomy and foraminoplasty. spinecenter.com Endoscopic Anterior Cervical Discectomy (AECD) Surgical Technique: • • Patient Positioning and surgical portal of entry Needle and stylette placement into the disc under Grid Position System (GPS) • Supine position with hyperextension of neck • Digital retraction of trachea/esophagus, and the carotid artery under the first two fingers • Systolic arterial pressure maintained at 130+ ephedrine may be used to maintain BP • • 45° Needle and stylette inserted into the disc aided by GPS, under fluoroscopy and EMG 20° N/G tube is placed in the esophagus to avoid injury GPS spinecenter.com AECD Surgical Technique: • • • • • • • Small 3mm skin incision The spinal needle with a thin stylette is introduced into the center of the disk Under fluoroscopy Provocative discogram is often done first The working cannula/dilator are passed over the stylette gently (dilatation technology) Mechanical microdecompressive discectomy to follow Completed with laser thermodiskoplasty (LTD) to shrink and to tighten the disc besides sinu-vertebral denervation spinecenter.com AECD Surgical Technique: Endoscopic/fluoroscopic/imaging monitoring to provide safe and precise application of aggressive micro grasper forceps, drill, curette, discectome, and bony ronguer for microdecompression spinecenter.com Endoscopic Cervical Microdiscectomy and Foraminoplasty Procedure – Step by Step - A Discogram demonstrated double shadow of large extruded disc/osteophytes Micro-drill and forceps for microdecompression of disc/osteophyte spinecenter.com Endoscopic Cervical Microdiscectomy and Foraminoplasty Procedure – Step by Step - B Microdecompression along posterior spinal canal with safety ronguer, drill and forceps spinecenter.com Endoscopic Cervical Microdiscectomy and Foraminoplasty Procedure – Step by Step - C Final removal of disc fragments/debris with ronguer, forceps, laser thermodiskoplasty, irrigation and cleaning with a discectome spinecenter.com AECD Surgical Technique: “Fan Sweep Maneuver” • For maneuvering instrument to precisely increase the area for microdecompressive discectomy spinecenter.com AECD Surgical Technique: Endoscopic Microdiscectomy – Laser Thermodiskoplasty (LTD) • • • Mechanical microdecompressive discectomy Herniated disc fragment removal Laser Thermodiskoplasty – disc shrinkage and tightening spinecenter.com AECD Surgical Technique: Cervical Foraminoplasty Cervical Foraminal Decompression for Foraminal Disc and Stenosis • Mechanical decompressive discectomy foraminoplasty for osteophytes/stenosis under fluoroscopy, endoscopy and IOM Microdiscectomy forceps Discectome Micro cutting forceps Micro curette Trephine for osteophytectomy Burr for osteophyte decompression spinecenter.com AECD Surgical Technique: • Endoscopic views of uncinate joint and nerve root after disc decompression, and fissure in cervical disc LTD defect Uncinate joint Nerve root Fissure Disc Disc Intra operative endoscopic view of fissure in cervical disc Uncinate joint and nerve root after endoscopic microdecompressi on spinecenter.com AECD Surgical Technique: Protocols for laser thermodiskoplasty (LTD) Level Stage Watts Joules Cervical First Stage 8 300 Cervical Second Stage 5 200 Holmium YAG laser with photo thermal effect and mechanism: • Absorbed by water • A pear shaped cavitation bubble formed by vaporization of water molecules, undergoes expansion and collapse - resulting in acoustic and shock wave emission • Simultaneously a vapor channel is formed that effectively conducts laser energy to the target with a pressure effect • Continuous cold saline irrigation is necessary spinecenter.com AECD Surgical Technique: Surgical technique of LTD, fan sweep maneuver and endoscopic views of disc shrinkage Side fire laser probe in action “Fan sweep maneuver” of instrument increased disc removal and shrinkage Laser used to shrink and tighten the disc besides “purse string” of the disc defect spinecenter.com AECD Post Operative Care: • Ambulatory usually in about one hour and discharged subsequently • May shower the following day • May use a cervical collar in a vehicle or on a flight as needed • Ice pack is helpful • Mild analgesics and muscle relaxant are required at times • Progressive spine exercise second post operative day on • Rehabilitation compliments MISS and motion preservation • Allowed to return to work in one to two weeks (not for heavy work) spinecenter.com AECD Surgical Outcome: • For 2169 patients, average follow-up 46 months (6-75 months) • Overall result: 1952(90%) patients with good to excellent results, fair results 130(6%) patients (single level) • Various evaluations/tests of response to treatment: modified Mac Nab criteria, Oswestry disability score/index (ODI), visual analogue pain scale (VAS), patient satisfaction scoring, pain diagram and/or patient target achievement score (PTA) for assessment were utilized • Average satisfaction score – 2309 (94% ) patients • 98 (4.5%) patients had mild residual pain and parasthesia, although overall their pain lessened • Complication rate: less than 1% • Average return to work: ten days spinecenter.com Case Illustration I – Octogenarian w/herniated C5-6 disc/osteophyte: 81 yo NS Professor underwent successful laser endoscopic cervical discectomy in spite of transient extreme bradycardia (30), detected, monitored and corrected with atropine in the DOR. Discharged on hour later Intra operative monitor shows severe dropping of heart rate spinecenter.com Case Illustration II – JDHS C3, C4 & C6 • 54 year old female suffering post fusion junctional disc herniation syndrome (JDHS) (after C5 & C6 corpectomy, discectomy and bone graft of C5-C6) at C3, C4 & C6 levels with severe radiculopathy • Complete relief of spinal symptoms after AECD and foraminoplasty at C3, C4 & C6 level spinecenter.com Case Illustration III - Herniated C5-6 disc: 50 yo female under went successful endoscopic microdecompressive cervical discectomy for a large herniated C5-6 disc spinecenter.com Case Illustration IV- Large herniated C3-4 disc: English rock star had successful endoscopic cervical discectomy C3-4 with hypoplastic odontoid process spinecenter.com Case Illustrations V • • Large herniated C5-6 disc: 44 year old female with increasing intraticable neck and upper extremity pain and numbness of fingers, mild spastic gait and weakness of hand grip, mild hyper reflexia, and hypoesthesia AECM - post operatively rapid improvement and disappearance of all symptoms Pre operative MRI scan - Large 5 mm herniated C5-6 disc compressing spinal cord with myelopathic changes of the spinal cord spinecenter.com Case Illustration VI • • Large herniated C5-6 disc: 35 year old male rock star with increasing intraticable neck and upper extremity pain and numbness of fingers, unable to perform AECM and left C5-6 foraminal decompressive discectomy and foraminoplasty gave immediate relief of all symptoms Pre operative MRI scans - Large foraminal herniated C5-6 disc compressing C6 nerve root spinecenter.com Discussion: • New biotechnology, instrument advances and accumulation of endoscopic spinal surgical experience, make the procedure of AECD and foraminal decompression (foraminoplasty) possible • Open cervical spinal surgery/fusion results in higher complication and morbidity besides longer convalescence • Post cervical spinal fusion patient, has high as 25 – 52% of them developed Junctional Disc Herniation Syndrome (JDHS) or Adjacent Segmental Disease (ASD) within 3-4 years • AECD MISS is an effective alternative or replacement for open spinal surgery for discectomy and decompression of stenosis in degenerative spine disease spinecenter.com Discussion: • As demonstrated in a multi-center endoscopic cervical spinal disc surgeries had an overall success rate of 91% (single level) • With a complication rate of less than 1%, zero mortality, satisfaction score, over 90% (for single and multi-levels) • Second operation required only in 0.79% • Resuming usual activity in a few days and full active lives in 2-6 weeks • These procedures can be extremely gratifying for patients and surgeon • Soon spinal arthroplasty, spinal motion preservation and dynamic stabilization can become an integral part of all cervical spinal surgery spinecenter.com AECD Discussion: • • • • • • • In order to perform AECD and to avoid potential complications, one must have a thorough knowledge of laser endoscopic cervical spinal procedures and the surgical anatomy Endoscopic cervical MISS has its unique surgical skill set Requiring the surgeon to go through a steep learning curve Careful patient selection Careful preoperative surgical planning Fluoroscopy as “The 3rd Eye” or “Eye of Wisdom” for confirmation of location of instruments; endoscopy alone is not enough These surgical procedures must be meticulously executed spinecenter.com POTENTIAL COMPLICATIONS AND THEIR AVOIDANCE • Excessive sedation: – Continuous conscious EEG monitoring with the new computerized SNAP™ monitoring (SNAP index) improves anesthesia and reduces drug requirement – Local anesthesia with conscious sedation provides a responsive patient to facilitate endoscopic MISS and prevents potential complications Surface EEG monitoring (SNAP™) spinecenter.com POTENTIAL COMPLICATIONS AND THEIR AVOIDANCE • Discitis: – Prophylactic antibiotics – Continuous irrigation of the interspace – Introduction of instruments through a cannula without contact with the skin • Aseptic discitis: – Aim the laser in a “bowtie” fashion to avoid damaging the endplates (at 6 and 12 o’clock) spinecenter.com POTENTIAL COMPLICATIONS AND THEIR AVOIDANCE • Spontaneous Cervical Fusion: secondary to using larger working channel, trephine (5mm or more) and trauma to the endplate causes spontaneous fusion at C6-C7 spinecenter.com POTENTIAL COMPLICATIONS AND THEIR AVOIDANCE • Neural Injury: extremely rare – No spinal cord injuries reported – Nerve root and spinal cord injury, though possible, but avoidable – With neurophysiologic monitoring (EMG/NCV) – Root injury avoided by introducing instruments in the “safety zone” – And direct endoscopic visualization – By frequent use C-arm fluoroscopy – Recurrent laryngeal nerve injury, is extremely rare – Postoperatively one case of transient hoarseness – One case with transient hiccough Uncinate joint and nerve root after endoscopic microdecompression Continuous intraoperative neurophysiologic monitoring (EMG/NCV) Intra operative endoscopic view of fissure in cervical disc spinecenter.com POTENTIAL COMPLICATIONS AND THEIR AVOIDANCE • • Sympathetic nerve injury: – Rare but can occur from injury to cervical sympathetic and Stellate Ganglions – One post-operative transient Horner syndrome or oculo sympathetic dysfunction occurred Esophageal and trachea injury due to trauma or perforation can occur: – But are avoided by careful surgical technique and by identifying and retracting these structures – By careful digital palpation and retraction at the site of needle insertion – By placing a nasogastric tube into the esophagus aids in identifying and retracting that structure by palpation. spinecenter.com Conclusion: • • • • • AECD has proven to be safe, less traumatic, easier, and efficacious For treatment of intractable spinal pain secondary to herniated cervical discs, and degenerative cervical spinal disease/foraminal stenosis It preserves spinal segmental motion, avoids JDHS, and provides an excellent access for spinal arthroplasty Utilization of intraoperative neurophysiological monitoring, IOM in a DOR prevents neurological injury and provides a safer MISS With proper surgical training and experience, it is a smart way to perform cervical spinal surgery spinecenter.com Hope you enjoyed this presentation! “Gracias por su amable atención” “Arigato” “Danke schön” “Cám ón” “Thank you” “Gracias” “Merci” John C. 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