research article minimally invasive scoliosis surgery: a...

Research ArticleMinimally Invasive Scoliosis Surgery A Novel Technique inPatients with Neuromuscular Scoliosis

Vishal Sarwahi1 Terry Amaral1 Stephen Wendolowski1 Rachel Gecelter1

Melanie Gambassi1 Christos Plakas2 Benita Liao3 Sarika Kalantre4 and Chhavi Katyal5

1Division of Pediatric Orthopedics Cohen Childrenrsquos Medical Center New Hyde Park NY 11040 USA2Department of Orthopaedic Surgery Childrenrsquos Hospital at Montefiore and Albert Einstein College of MedicineBronx NY 10467 USA3Department of Pediatric Anesthesiology Cohen Childrenrsquos Medical Center New Hyde Park NY 11040 USA4Division of Pediatric Cardiology Childrenrsquos Hospital at Montefiore and Albert Einstein College of Medicine Bronx NY 10467 USA5Division of Critical Care Department of Pediatrics Childrenrsquos Hospital at Montefiore and Albert Einstein College of MedicineBronx NY 10467 USA

Correspondence should be addressed to Vishal Sarwahi vsarwahinshsedu

Received 7 August 2015 Revised 6 October 2015 Accepted 15 October 2015

Academic Editor Roberto Delfini

Copyright copy 2015 Vishal Sarwahi et alThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Minimally invasive surgery (MIS) has been described in the treatment of adolescent idiopathic scoliosis (AIS) and adult scoliosisThe advantages of this approach include less blood loss shorter hospital stay earlier mobilization less tissue disruption andrelatively less pain However despite these significant benefits MIS approach has not been reported in neuromuscular scoliosispatients This is possibly due to concerns with longer surgery time which is further increased due to more levels fused andinstrumented challenges of pelvic fixation size and number of incisions and prolonged anesthesiaWemodified theMIS approachutilized in our AIS patients to be implemented in our neuromuscular patients Our technique allows easy passage of contouredrods placement of pedicle screws without image guidance partialcomplete facet resection and all standard reduction maneuversOperative time needed to complete this surgery is comparable to the standard procedure and themajority of our patients have beenextubated at the end of procedure spending 1 day in the PICU and 5-6 days in the hospital We feel that MIS is not only a feasiblebut also a superior option in patients with neuromuscular scoliosis Long-term results are unavailable however short-term resultshave shown multiple benefits of this approach and fewer limitations

1 Introduction

MIS technique in AIS has been shown to provide similarcorrection and pedicle screw accuracy with lower blood lossand rate of transfusion [1] In adult scoliosis patients short-term benefits such as less pain narcotics usage and shorterhospital stay have also been reported [2]These benefits seemideal for patientswith neuromuscular scoliosis who routinelyspend more days in the ICU and in the hospital requireprolonged intubation have increased blood loss and requiremultiple units of blood transfusion [3ndash5] However curves inchildren with neuromuscular scoliosis are usually larger andstiffer with more number of levels fused and instrumented(16ndash18) and a need for pelvic fixation [5] The length and

type of skin incision are also important The standard stabincision for placement of percutaneous pedicle screws cannotbe utilized as passing a rod that is contoured in the normalsagittal profile (thoracic kyphosis and lumbar lordosis) will bequite challenging and thirty-two to thirty-eight stab incisionsin the back for screw insertion are less than desired

In MIS technique for AIS patients the skin incisionshave beenmodified to three noncontiguousmidline incisionsthrough which 2ndash4 levels (4ndash8 screws) can be fused utilizinga muscle splitting approach [6] The pedicle screws areinserted in a free hand anatomic manner obviating theneed for fluoroscopy and the technique allows for partial orcomplete facet osteotomyexcision [6] Adequate fusion hasbeen documented on CT scans as the fusion bed comprises

Hindawi Publishing CorporationBioMed Research InternationalVolume 2015 Article ID 481945 6 pageshttpdxdoiorg1011552015481945

2 BioMed Research International

Figure 1 Intraoperative image showing the modification of skinincision to facilitate instrumentation

the facet joint pars and variable areas of transverse processand lamina while preserving the midline osteoligamentouscomplex [6] This approach also allows multiple reductionmaneuvers including rod translation rod derotation in situbending direct vertebral rotation and spine translation [6]However despite all the advantages and feasibility of thetechniqueMIS approach inAIS takesmuch longer which hasthus far limited its application in neuromuscular scoliosis

The purpose of this study is to detail a modificationof the previously described technique for minimally inva-sive posterior spinal fusion allowing its application in theneuromuscular scoliosis patient population with comparablelength of surgery

2 Materials and Methods

We have been utilizing minimallyless invasive spine surgerytechniques in neuromuscular scoliosis patients for aroundone year This technique allows for all standard reductionmaneuvers rod insertion free hand anatomic insertion ofpedicle screws withwithout image guidance adequate facetosteotomy to enable fusion facet joint excision for stiffercurves and pelvic fixation

21 Surgical Technique A single midline curvilinear skinincision is made for instrumentation of sixteen to eighteensegments following the deformity (Figure 1)

The skin is undermined and mobilized on either side ofmidline to allow for the placement of pedicle screws on bothsides The muscle dissection is started in the lumbar spinewhere the facet can be manually palpated A stab incision inthe fascia is made directly over the facet and muscle planeis developed bluntly between multifidus and longissimus coliwith a Cobb elevator or an insulated electrocautery (Figures2 and 3)

The facet joint is exposed and a small Gelpi retractor isinserted Further dissection is carried out as needed to exposethe adjacent transverse process and portion of the laminaWetake advantage of the overlapping spine anatomy in locatingthe facet joints at the level above and at the level below Themidline osteoligamentous structures are preserved Furtherdissection is extended caudally and cranially to exposeadditional levels This approach thus creates a paramedianexposure similar to Wiltse approach along the entire lengthof the spine and also the posterior superior iliac spine Inthe thoracic spine the fibers of latissimus dorsi and trapezius

M L

Figure 2 MRI axial image of the lumbar spine with the block arrowpointing to the facet joint which is the most prominent area afterthe spinous process and is easily palpable after the lumbar fasciais incised The thin arrow denotes the plane of dissection betweenmultifidus medially (M) and longissimus laterally (L) This plane isapproximately 2 to 25 cm lateral to the midline

ML

Figure 3 MRI axial image of the thoracic spine showing the facetjoint (large block arrow) which is less prominent than the transverseprocess (small block arrow)The plane of dissection (dashed arrow)is between multifidus medially (M) and longissimus laterally (L)Also notice the fibers running transversely of the trapezius whichlies superficially to the thoracodorsal fascia and has to be incised toexpose the surgical plane

need to be dissected before reaching the thoracodorsal fasciaThe longitudinal fibers can be split after the fascia is incisedto expose the facet joint After the facet joint is exposed afacetectomy is performed with either a 1410158401015840 osteotome ora high speed burr Adequate excision of the facet joint iscarried out to ensure a solid fusion The adjacent transverseprocess pars and portion of lamina are decorticated to createa sizeable fusion bed after the muscle fibers are elevated withBovie if needed The fusion bed thus extends from the tipof the transverse process laterally to lamina medially andincludes the facet joint and pars interarticularis This fusionbed area reaches comparable size to standard techniquesexcept for the spinous process which is often excised bysurgeons in the standard technique

Pedicle screws are placed utilizing the free hand techniquebut can be inserted under fluoroscopy (Figure 4)

Complete exposure of the transverse process is usuallynot needed to identify the entry point but can be carried

BioMed Research International 3

Figure 4 Intraoperative image showing pedicle screws that havebeen inserted utilizing free hand anatomic technique on the left sideat multiple levels

Figure 5 A close-up view of the lumbar spine with rod reductioninstruments attached to the pedicle screws at the time of rodinsertion

out if desired Sacral screw insertion is carried out in afree hand manner but can also be done under fluoroscopyfor a tricortical approach Pelvic fixation can be carried outsimilarlyThe PSIS serves as an attachment formultifidus andthus the dissection plane leads to the entry pointWe prefer toplace pelvic screws under intermittent fluoroscopy to directthe screw towards dense bone superior to the sciatic notchTwo rods cut to appropriate length are contoured in thenormal sagittal plane and are inserted caudad to cephaladWe start with the concave rod first A rod translation orrod derotation maneuver can be carried out to seat the rodcompression and distraction as needed can also be carriedout In situ rod contouring can also be carried out but is notour preference Direct vertebral rotation maneuver is thencarried out off the concave-side screws (Figures 5 and 6)

A mix of allograft and autograft mixed with vancomycinpowder is layered after burring the posterior portion ofspine Closure is fairly rapid and is carried out in a layeredfashion We utilize subcutaneous medium hemovac drainIntraoperative anteroposterior and lateral X-rays are takento confirm adequate correction An assessment is made atthe end of the case about extubating the patient and in mostcases is carried out in the operating room We prefer to useKetorolac (Toradol Roche Laboratories Nutley NJ) ratherthan morphine for analgesia We do not brace our patientsand child is allowed sitting andor wheelchair transfers nextday Activity is increased gradually as tolerated within thelimits of pain Patients can return to school in 3-4 weeks

Figure 6 Rods have been inserted on both of the sides and correc-tion has been obtained Notice that the midline osteoligamentousstructures have been preserved

Figure 7 Preoperative radiographs showing a 54-degree scoliosisdeformity in a patient with Rett syndrome Patient has coronalimbalance The pelvis is level

3 Results

We present two case examples to show the degree of cor-rection and benefits of MIS technique in neuromuscularscoliosis In our first case the patient is an 11-year-old girl witha 54∘ right-sided long C shaped curve (Figure 7)

She had underlying diagnoses of Rett syndrome Patientwas noncommunicative but was able to ambulate indepen-dently Patient hadminimal pelvic obliquity 54 cmof coronalimbalance and normal sagittal parameters Patient under-went posterior spine fusion fromT3-S1 utilizing pedicle screwinstrumentation and the approach described above Mul-timodality neuromonitoring was utilized with no changesthroughout the surgery Total duration was 5 hours andestimated blood loss was 600mL Patient received 1 unit ofpacked red blood cells intraoperatively and was successfullyextubated at the end of the procedure Her PICU stay was oneday and she was able to get out of bed and ambulate with awalker on POD 2 Her pain was controlled with Tylenol andToradol around the clock with oxycodone for breakthroughpain She was discharged home on POD 4 with her paincontrolled on oral medication At most recent follow-up shewas at her preoperative levels of activity ambulating and


Figure 8 Immediate postoperative radiographic images showingexcellent correction of the deformity Patient is well-balanced incoronal and sagittal planes The pelvis and shoulder are level

with no significant pain Postoperative X-rays are shown inFigure 8

In our second case a 135-year-old girl with a 100∘ right-sided main thoracic curve (T6-L1) underwent minimallyinvasive surgery for correction of her spinal deformity Shepresented with cerebral palsy in addition to a history ofseizures developmental delay and a recent diagnosis ofobstructive sleep apnea (Figure 9)

Moreover the patient is nonverbal nonambulatory feed-ing tube dependent and asthmatic Using a similar approachthe patient was instrumented with pedicle screws from T3-S1No remarkable neuromonitoring changes occurred duringthe surgery Total surgical duration was 7 hours with an esti-mated blood loss of 800mL Patient received 2 units of packedred blood cells and 1 unit of platelets intraoperatively Patientwas extubated POD 1 and was transferred to the floor Painmanagement was similar to the previously described casePatient was discharged on POD 5The postoperative X-raysdemonstrate pelvic fixation and show good correction in thecoronal and sagittal planes (Figure 10)

4 Discussion

Patients with neuromuscular scoliosis experience higherrates of complications prolonged ICU stay and increasedblood loss Jain et al grouped 617 patients with differentdiagnosis to assess the relationship between diagnosis andblood loss in children undergoing posterior spinal fusionsurgery They found that patients with cerebral palsy andother neuromuscular disorders had a significantly highernormalized blood loss than patients with idiopathic scoliosis[7] Edler et al [5] compared 163 neuromuscular patientswith 80 nonneuromuscular patients They found that 65 ofneuromuscular patients lostmore than 50of their estimatedblood volume Modi et al reported a mean blood loss of3221 plusmn 1711mL in their review of 50 patients with neu-romuscular scoliosis who underwent posterior spine fusionusing all pedicle screw construct [8] Twenty of their patients

had blood loss of 3500mL or more which they found tobe a clear determinant of postoperative complications[8]Tsirikos and Mains reviewed 45 consecutive patients withquadriplegic cerebral palsy who underwent spinal fusionusing pedicle screw instrumentation Thirty-eight patientsunderwent posterior spine fusion while 7 underwent stagedanterior and posterior spine fusionThey reported an averagecorrection of 741 overall with average blood loss of 08blood volumes ICU stay of 35 days and hospital stay of176 days in posterior-only group In anteroposterior groupthe average blood loss was 09 blood volumes ICU stay was89 days and hospital stay was 274 days [9] Tsirikos et alcarried out a retrospective review of 287 patients treated withthe unit rod instrumentation with 242 posterior-only and45 anterior-posterior procedures They reported an average68 correction of the deformity In posterior-only fusionthe average blood loss was 28 L ICU stay was 49 daysand the hospital stay was 196 days In combined proceduresthe average blood loss was 34 L ICU stay was 67 daysand the hospital stay was 245 days [10] Hammett et alretrospectively reviewed 11 patients with Rett syndrome whounderwent scoliosis surgery The average age of the cohortwas 12 Eight of their patients suffered one ormore significantcomplications with an average inpatient stay of 182 days[11] Rumbak et al reviewed patients with Rett syndromeundergoing scoliosis surgery in regard to rates of respiratoryfailure and rates of ventilator-acquired pneumonia in com-parison to patients with neurologic scoliosis and adolescentidiopathic scoliosis There were 133 patients with adolescentidiopathic scoliosis 48 patients with neurologic scoliosisand 8 patients with Rett syndrome They found that patientswith Rett syndrome undergoing scoliosis surgery have higherrates of respiratory failure and longer ventilation times in thepostoperative period when compared with both adolescentidiopathic scoliosis and neurologic scoliosis patients [12]

Considering the reported advantages of the MIS tech-nique in AIS and adult scoliosis surgery it is intuitiveto apply the benefits in neuromuscular scoliosis Certainlyless blood loss and pain can impact the amount of painmedications fluids and even the duration of intubationin these compromised children However MIS techniquein neuromuscular scoliosis has thus far not been reportedlargely due to concern for prolonged surgery and anesthesiawhich can increase the blood loss fluids and risk of infectionAlso it is challenging to pass a curved rod over 12-13 segmentsthrough small incisions and to pass it over 16ndash18 segmentsand the pelvic fixation appears quite daunting We havetherefore modified the MIS for AIS approach and haveutilized it in neuromuscular patients Instead of multipleskin incisions we now use a single midline incision thatfollows the curve After this the dissection is between themultifidusmedially and longissimus laterally Since this planeexists naturally the dissection involves separation of themuscles and is quite bloodless Occasionally a small leash ofblood vessel is seen on the surface of longissimus and canbe coagulated preemptively Instead of making separate stabincisions in the fascia which is done in the MIS approachwe make a longitudinal incision along the muscle plane Wefind that multiple stab incisions made over adjacent levels


Figure 9 Preoperative radiographs showing a 100-degree scoliosis deformity in a severely involved cerebral palsy patient The patient haspelvic obliquity of 15 degrees with significant coronal decompensation Patient is nonambulatory with unilateral hip dislocation

Figure 10 Immediate postoperative radiograph images showingspinal fusion and instrumentation from T3-S1 with significantimprovement of the deformity Unilateral pelvic fixation was carriedout in this patient

tend to coalesce leading to a long incision in the fascia alongthe muscle plane Thus single long fascial incision makesthe dissection neat and efficient In the thoracic spine thecrossing fibers of latissimus dorsi and trapezius overlie thethoracodorsal fascia and they need to be dissected to allowaccess to the facet joint Generally the facet joints lie 15ndash2 cm from the midline on the concave side and 2ndash25 cmon the convex side As the dissection proceeds caudally thisdistance becomes smaller In the lumbar spine the facet jointslie more superficial to the transverse process and are easilypalpable whereas in the thoracic spine the transverse processis more prominent Thus we prefer to start in the lumbarand thoracolumbar spine and extend cephalad following theoverlapping spine anatomy to expose thoracic spine facets

It can be argued that the size of the skin incision does notdetermine minimally invasive technique Minimally invasiveapproach in this patient population refers to preservation of

tissues utilization of the preexisting muscle planes and lessdisruptive and traumatic dissection This leads to a lesseramount of pain and blood loss which is determinant ofcomplications in this group of patients [8] We have utilizedthe MIS technique on curves up to 100 degrees and evenin children with severe disease involvement For curves gt70degrees or smaller but less flexible curves we have utilizedpreviously described transforaminal type osteotomyfacetresection [6] The entire facet facet joint capsule and mostligamentum flavum can be excised which increases theflexibility and can be carried out at multiple levels Themidline ligamentous and bony structures are preserved [6]

The highlight of this surgical technique paper is theimmense perioperative benefit it accrues to children withneuromuscular scoliosis who are otherwise at a much higherrisk for morbidity and mortality The weaknesses are theshort-term follow-up and concerns of loss of correction evennonunion We are presenting this as a surgical techniquepaper with two case reports showing significant advantagesfor a challenged population Our technique has lower bloodloss lesser transfusion risk and comparable operative timeIn addition patients have lower pain medication require-ments stay in the ICU for one day and can be dischargedhome in 4ndash6 days These advantages are due to bettersoft tissue preservation utilizing intermuscular planes fordissection which decreases bleeding and pain This in turnhelps with ICU and hospital stay and pain medicationsThese combined benefits are much superior to those whichhave been previously reported and are worthy of reportingeven with short-term follow-up This technique paper hencefocuses on the surgical approach and perioperative benefitsThepseudarthrosis rate previous to pedicle screwfixationwasaround 10 [13]With pedicle screw fixation nonunion is rareand is usually associated with deep infection Our techniqueis no different than the standard method in terms of fixationand is comparable to fusion area but its perioperative benefitsare far superior and can potentially change the outcomes inneuromuscular scoliosis which are otherwise riddled withmajor medical complications


Our results indicate that good correction in coronal andsagittal planes can be achieved safely In curves that areflexible 75ndash80 correction can be achieved However thegreatest benefit of this technique is less blood loss shorterPICU and hospital stay earlier mobilization and less painand need for pain medication [1] The operative time neededto complete this surgery is comparable to standard scoliosissurgery [1 2]

5 Conclusion

Minimally invasive approach seems to provide the greatestbenefits to patients with neuromuscular scoliosis in terms ofblood loss pain and ICU and hospital stay A longer-termstudy is currently underway at our institution

Conflict of Interests

Vishal Sarwahi is a Consultant at Medtronic and Spinal USAand receives royalties from Spinal USA All the other authorshave no conflict of interests to declare

References

[1] V Sarwahi J J Horn P M Kulkarni et al ldquoMinimally invasivesurgery in patients with adolescent idiopathic scoliosis is itbetter than the standard approach A two year follow-up studyrdquoJournal of Spinal Disorders and Techniques 2014

[2] N Anand R Rosemann B Khalsa and E M Baron ldquoMid-term to long-term clinical and functional outcomes of mini-mally invasive correction and fusion for adults with scoliosisrdquoNeurosurgical focus vol 28 article E6 2010

[3] N A Murphy S Firth T Jorgensen and P C Young ldquoSpinalsurgery in children with idiopathic and neuromuscular scol-iosis Whatrsquos the differencerdquo Journal of Pediatric Orthopaedicsvol 26 no 2 pp 216ndash220 2006

[4] D L Reames J S Smith K-M G Fu et al ldquoComplicationsin the surgical treatment of 19360 cases of pediatric scoliosisa review of the Scoliosis Research Society Morbidity andMortality databaserdquo Spine vol 36 no 18 pp 1484ndash1491 2011

[5] A Edler D J Murray and R B Forbes ldquoBlood loss during pos-terior spinal fusion surgery in patients with neuromuscular dis-ease is there an increased riskrdquo Paediatric Anaesthesia vol 13no 9 pp 818ndash822 2003

[6] V Sarwahi A LWollowick E P Sugarman J J HornMGam-bassi and T D Amaral ldquoMinimally invasive scoliosis surgeryan innovative technique in patients with adolescent idiopathicscoliosisrdquo Scoliosis vol 6 article 16 2011

[7] A Jain D B Njoku and P D Sponseller ldquoDoes patientdiagnosis predict blood loss during posterior spinal fusion inchildrenrdquo Spine vol 37 no 19 pp 1683ndash1687 2012

[8] H N Modi S-W Suh J-H Yang et al ldquoSurgical complica-tions in neuromuscular scoliosis operated with posterior- onlyapproach using pedicle screw fixationrdquo Scoliosis vol 4 article 112009

[9] A I Tsirikos and E Mains ldquoSurgical correction of spinal defor-mity in patients with cerebral palsy using pedicle screw instru-mentationrdquo Journal of Spinal Disorders amp Techniques vol 25no 7 pp 401ndash408 2012

[10] A I Tsirikos G Lipton W-N Chang K W Dabney and FMiller ldquoSurgical correction of scoliosis in pediatric patientswith cerebral palsy using the unit rod instrumentationrdquo Spinevol 33 no 10 pp 1133ndash1140 2008

[11] T Hammett A Harris B Boreham and S M H MehdianldquoSurgical correction of scoliosis in Rett syndrome cord mon-itoring and complicationsrdquo European Spine Journal vol 23 no1 pp S72ndashS75 2014

[12] D M RumbakWMowrey S W Schwartz et al ldquoSpinal fusionfor scoliosis in rett syndrome with an emphasis on respiratoryfailure and opioid usagerdquo Journal of Child Neurology 2015

[13] J E Lonstein S E Koop T F Novachek and J H PerraldquoResults and complications after spinal fusion for neuromuscu-lar scoliosis in cerebral palsy and static encephalopathy usingluque galveston instrumentation experience in 93 patientsrdquoSpine vol 37 no 7 pp 583ndash591 2012

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Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom


Figure 1 Intraoperative image showing the modification of skinincision to facilitate instrumentation

the facet joint pars and variable areas of transverse processand lamina while preserving the midline osteoligamentouscomplex [6] This approach also allows multiple reductionmaneuvers including rod translation rod derotation in situbending direct vertebral rotation and spine translation [6]However despite all the advantages and feasibility of thetechniqueMIS approach inAIS takesmuch longer which hasthus far limited its application in neuromuscular scoliosis

The purpose of this study is to detail a modificationof the previously described technique for minimally inva-sive posterior spinal fusion allowing its application in theneuromuscular scoliosis patient population with comparablelength of surgery

2 Materials and Methods

We have been utilizing minimallyless invasive spine surgerytechniques in neuromuscular scoliosis patients for aroundone year This technique allows for all standard reductionmaneuvers rod insertion free hand anatomic insertion ofpedicle screws withwithout image guidance adequate facetosteotomy to enable fusion facet joint excision for stiffercurves and pelvic fixation

21 Surgical Technique A single midline curvilinear skinincision is made for instrumentation of sixteen to eighteensegments following the deformity (Figure 1)

The skin is undermined and mobilized on either side ofmidline to allow for the placement of pedicle screws on bothsides The muscle dissection is started in the lumbar spinewhere the facet can be manually palpated A stab incision inthe fascia is made directly over the facet and muscle planeis developed bluntly between multifidus and longissimus coliwith a Cobb elevator or an insulated electrocautery (Figures2 and 3)

The facet joint is exposed and a small Gelpi retractor isinserted Further dissection is carried out as needed to exposethe adjacent transverse process and portion of the laminaWetake advantage of the overlapping spine anatomy in locatingthe facet joints at the level above and at the level below Themidline osteoligamentous structures are preserved Furtherdissection is extended caudally and cranially to exposeadditional levels This approach thus creates a paramedianexposure similar to Wiltse approach along the entire lengthof the spine and also the posterior superior iliac spine Inthe thoracic spine the fibers of latissimus dorsi and trapezius

M L

Figure 2 MRI axial image of the lumbar spine with the block arrowpointing to the facet joint which is the most prominent area afterthe spinous process and is easily palpable after the lumbar fasciais incised The thin arrow denotes the plane of dissection betweenmultifidus medially (M) and longissimus laterally (L) This plane isapproximately 2 to 25 cm lateral to the midline

ML

Figure 3 MRI axial image of the thoracic spine showing the facetjoint (large block arrow) which is less prominent than the transverseprocess (small block arrow)The plane of dissection (dashed arrow)is between multifidus medially (M) and longissimus laterally (L)Also notice the fibers running transversely of the trapezius whichlies superficially to the thoracodorsal fascia and has to be incised toexpose the surgical plane

need to be dissected before reaching the thoracodorsal fasciaThe longitudinal fibers can be split after the fascia is incisedto expose the facet joint After the facet joint is exposed afacetectomy is performed with either a 1410158401015840 osteotome ora high speed burr Adequate excision of the facet joint iscarried out to ensure a solid fusion The adjacent transverseprocess pars and portion of lamina are decorticated to createa sizeable fusion bed after the muscle fibers are elevated withBovie if needed The fusion bed thus extends from the tipof the transverse process laterally to lamina medially andincludes the facet joint and pars interarticularis This fusionbed area reaches comparable size to standard techniquesexcept for the spinous process which is often excised bysurgeons in the standard technique

Pedicle screws are placed utilizing the free hand techniquebut can be inserted under fluoroscopy (Figure 4)

Complete exposure of the transverse process is usuallynot needed to identify the entry point but can be carried








3 Results








4 Discussion













5 Conclusion




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Disease Markers



OncologyJournal of





PPAR Research



Journal of

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Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of





















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Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

























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Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of





















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Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of
















research article minimally invasive scoliosis surgery: a...

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