Wiltse Paraspinal Approach Research Articles

Microsurgical Wiltse Paraspinal Approach Using a Low-Budget Exoscope.

Access to microneurosurgical care in low- and middle-income countries remains limited mainly due to a lack of equipment. High purchasing and maintenance costs hinder the use of operating microscopes in low-resource facilities. The authors present an improved version of their previously introduced low-cost exoscope to achieve high magnification and illumination in low-resource environments. The setup included a 48-megapixel two-dimensional digital microscope camera, a wide field C-mount lens, ring light, and a two-link cantilever with a screw terminal. The surgical field was projected to a portable 17.3-inch 2K resolution monitor. Ten patients underwent exoscope-assisted transforaminal lumbar interbody fusion via the Wiltse paraspinal approach. The simple construction allowed a fast and intuitive preoperative setup. The in-plane switching type display provided a clear and bright image regardless of the viewing angle. The two-link arm of the cantilever allowed smooth positioning of the camera, overcoming the cumbersome up and down movements needed to zoom in and out with the previous prototype. Industrial microscope cameras are effective low-budget alternatives to conventional operating microscopes in lumbar microdiscectomy. The improved system is superior compared to the authors' previous prototype with regard to affordability, image quality, and adjustability of position and angle.

Technical note: A modified wiltse technique for minimally invasive surgery transforaminal lumbar interbody fusion

Background: Conventional midline dorsal approach to spine leads to excessive muscle retraction and hence muscular injury, denervation, atrophy, or ischemic necrosis. Wiltse paraspinal approach prevents these complications. We present a modified Wiltse approach using minimally invasive surgery techniques for fixation of lumbar spinal instability patients.Methods: Here, we provide a step wise description of the modified Wiltse approach. We then put together, a step wise analysis of the preparation, patient positioning, skin incision, fascial opening, dissection, bone identification, retractors, deprioritization, decompression, discectomy, instrumentation, arthrodesis, and closure for the Wiltse technique.Conclusion: The classical approach described by Wiltse is essentially minimally invasive, sparing both the muscle planes and soft tissues. Adding a modification with tubular retractor system gives an additional advantage of muscle-sparing discectomy and fusion with a very low complication rate.

The Clinical Effect of Manual Reduction Combined with Internal Fixation Through Wiltse Paraspinal Approach in the Treatment of Thoracolumbar Fracture.

ObjectiveTo evaluate the clinical outcome of manual reduction combined with pedicle fixation through Wiltse paraspinal approach (WPA) in the treatment of thoracolumbar fractures.MethodsFrom May 2017 to May 2019, 48 thoracolumbar fractures patients without neurological symptoms were enrolled in this study. Forty‐eight patients were randomly divided into two groups based on the different surgical treatment. Group 1 was manual reduction combined with pedicle screw fixation through Wiltse paraspinal approach treatment group. Group 2 was pedicle screw fixation through traditional posterior approach treatment group. The operation time (OT), intraoperative blood loss (BL), postoperative drainage (PD), time of brace (TB) and the cobb angle recovery of the injured kyphosis in the prone position were obtained and compared between the two groups, respectively. Comparison of cobb angle changes, serum creatine kinase (CK) level, pain visual analogue score (VAS), Oswestry disability index (ODI), and multifidus cross‐sectional (MCS) area changes were achieved between the two groups, respectively.ResultsForty‐eight patients were enrolled in this study and each group had 24 patients. There was no significant difference between the two groups in patient's age, height, weight, and body mass index (BMI). There were 20 males and four females in group 1. The mean age, height, weight, and BMI of patients were 61.99 ± 11.00 years (range, 42–75 years), 175.21 ± 4.49 cm, 76.71 ± 4.87 kg, and 24.98 ± 1.03 kg/m2 in group 1, respectively. Group 2 had 18 males and six females, and the mean age, height, weight, and BMI of patients were 57.95 ± 9.22 years (range, 44–77 years), 176.37 ± 4.56 cm, 77.42 ± 4.61 kg, and 24.87 ± 1.10 kg/m2 in group 2, respectively. The mean bleeding volume of group 1 was significantly less than group 2 (64.13 ± 9.77 ml and 152.13 ± 10.73 ml, respectively) (P < 0.05). The mean operation time, postoperative drainage, and time of brace were 62.95 ± 9.80 min, 66.25 ± 12.75 ml, and 3.62 ± 0.97 days in group 1, respectively, and they were significantly better than those of group 2 (69.29 ± 6.82min, 162.96 ± 14.55ml and 7.88 ± 1.94 days, respectively) (P < 0.05). The mean multifidus cross‐sectional area was significantly smaller than per‐operation after surgery in two groups (P < 0.05). The mean creatine kinase of group 1 was 403.13 ± 39.78 U/L and 292.12 ± 45.81 U/L at 1 and 3 days after surgery, respectively, which was significantly smaller than those in group 2 (654.25 ± 53.13 U/L and 467.67 ± 44.25 U/L, respectively) (P < 0.05). The Oswestry disability index of group 1 were significantly better than those in group 2 especially at 1 month and final follow‐up after surgery (P < 0.05). Moreover, group 1 also had better outcomes in postoperative Cobb angle change than those in group 2, with significant difference on intra‐operation, 1 day and 1 month post‐operation (P < 0.05).ConclusionIn short, this operation is suitable for thoracolumbar fractures without neurologic symptoms. Preoperative manual reduction had advantages of restoring the height of injured vertebrae. Wiltse intermuscular approach can reduce intraoperative blood loss, shorten operation time, and reduce paraspinal muscle damage. Using the traditional posterior approach, it is easy for surgeons to grasp this technique and it should be recommended as conforming with the minimally invasive approach of recent years.

Comparison of the modified Wiltse's approach with spinal minimally invasive system and traditional approach for the therapy of thoracolumbar fracture.

Thoracolumbar fractures are usually treated by open posterior pedicle screw fixation. However, this procedure involves massive paraspinal muscle stripping, inflicting surgical trauma, and prolonged X-ray exposure. In this study, we observed 127 patients with single-segment injury thoracolumbar fractures. Thirty-six patients were treated by the modified Wiltse's paraspinal approach with minimally invasive channel system, while 91 patients were treated via traditional posterior approach. Operation time, intraoperative blood loss, intraoperative fluoroscopy frequency, screw placement accuracy, visual analogue scale score, and Cobb's angle of two groups were compared. The X-ray exposure times were notably reduced (4.2±1.6) in the new approach group (P<0.05). The pedicle screw placement accuracy and Cobb's angle after surgery were similar in the two groups. We conclude that modified Wiltse's paraspinal approach with spinal minimally invasive channel system surgery can significantly reduce the X-ray exposure times and is an alternative therapy for the thoracolumbar fracture.

Large Retroperitoneal Hematoma and Lumbosacral Plexopathy Following Microsurgical Decompression via the Wiltse Paraspinal Approach: A Case Report

Journal of Minimally Invasive Spine Surgery & Technique (JMISST) is the official journal of the Korean Minimally Invasive Spine Surgery Society (KOMISS) for the publication of research results about minimally invasive spinal surgery (MISS), including studies in spinal endoscopic surgery, minimally invasive procedure for degenerative spine disease, pain intervention, and minimally invasive surgery for spinal fusion or spine trauma, neuroscience, neurology, molecular biology and biomechanics etc. Articles with helpful information for MISS such as reports of rare cases or technical review of special devices or equipment are also available

Corrigendum to "Microsurgical Foraminotomy via Wiltse Paraspinal Approach for Foraminal or Extraforaminal Stenosis at L5-S1 Level : Risk Factor Analysis for Poor Outcome" by Cho SI, et al. (J Korean Neurosurg Soc 59 : 610-614, 2016).

Corrigendum to "Microsurgical Foraminotomy via Wiltse Paraspinal Approach for Foraminal or Extraforaminal Stenosis at L5-S1 Level : Risk Factor Analysis for Poor Outcome" by Cho SI, et al. (J Korean Neurosurg Soc 59 : 610-614, 2016).

Comparison of pedicle screw fixation via paraspinal approach and traditional open approach for treatment of thoracolumbar fracture and dislocation

Objective To compare the clinical efficacy of posterior pedicle screw fixation through Wiltse paraspinal approach and posterior traditional open approach in the treatment of thoracolumbar fracture and dislocation. Methods A retrospective case control study was performed based on the clinical data of 40 patients with thoracolumbar fracture and dislocation admitted between January 2013 and January 2016. All the surgeries were performed through posterior midline incision, and they were divided into two groups according to different approaches. Patients in Group A received pedicle screw fixation through Wiltse paraspinal approach while Group B received fixed pedicle screw through open surgery. Group A was composed of 12 males and 8 females, aged 21-60 years [(41.5±9.6)years]. Group B was composed of 13 males and 7 females, aged 18-58 years [(39.1±13.1)years]. The same surgical procedures were adopted in spinal decompression, reduction, and the spinal vertebral interbody bone graft and fusion surgery in the two groups. Operation duration, intraoperative blood loss, postoperative drainage volume, visual analogue scale (VAS), spinal canal patency at the last follow-up, percentage of postoperative injury of vertebral height recovery, and Cobb angle were compared. CT and MRI were used to evaluate postoperative paravertebral muscle atrophy, and American spinal injury association (ASIA) impairment scale was used to evaluate neurological function assessment. Results All patients were followed up for 9-33 months, with (19.3± 5.6)months for Group A and (22.5±4.9)months for Group B (P>0.05). The operation duration was (240.5±38.3)min in Group A and (258.5±43.7)min in Group B (P>0.05). The intraoperative blood loss was (525.0±168.2)ml in Group A, less than (770.0±269.2)ml in Group B (P 0.05). In terms of MRI evaluation score of postoperative paravertebral muscle atrophy, Group A reported better results than Group B [(2.1±0.6)points vs. (1.2±0.6)points] (P 0.05). Within the same group, significant difference was observed between the preoperative data and that at the last follow-up in terms of postoperative VAS score, spinal canal patency, percentage of injury of vertebral height, Cobb angle, and ASIA impairment scale (P<0.05). Conclusion For thoracolumbar fracture and dislocation, compared with traditional open approach, posterior pedicle screw fixation through Wiltse paraspinal approach can effectively restore the vertebral body height and spinal canal patency and can reduce the intraoperative bleeding, postoperative drainage, postoperative back pain, and paravertebral lesion. Key words: Spinal injuries; Thoracic vertebrae; Lumbar vertebrae; Fracture fixation

Surgical Technique for Lumbar Spinal Extraforaminal Schwannoma

Spinal neurinomas are frequently observed in the cauda equina, particularly within the dura mater. However, extraforaminal schwannomas(EFS), which are neither intradural nor dumbbell type, are relatively rare; hence, different surgical procedures have been employed. Here, we report 12 cases of lumbar EFS with total resection that were safely performed. This study was comprised of 12 patients with lumbar EFS(excluding those with neurofibromas)who were previously treated at our hospital. Using the Wiltse paraspinal approach, we inserted the microscope until it reached the tumor surface. After confirming the tumor surface, we inserted a scalpel to make an incision in a portion of the outer capsule. Then, we confirmed that the surfaces of the outer capsule and the tumor within the capsule could be dissected. Next, a thread was attached to the outer capsule and pulled upwards so that there was enough space to perform the required procedures within the capsule. Using a CUSA^®, we removed the intracapsular tumor. After its removal, the outer capsule was treated carefully to ensure that the origin nerve was not damaged. In all cases, we successfully performed a total removal of the intracapsular tumor;in the mean postoperative observation period of 8 years, no recurrence was observed. Although temporary paralysis was observed in three patients, this improved over time. We report our experience with a surgical technique that ensured the safe removal of lumbar EFS. Satisfactory results were achieved, with no recurrences observed during the mean 8-year postoperative observation period.

How to perform the Wiltse posterolateral spinal approach: Technical note.

Background:The paraspinal, posterolateral, or Wiltse approach is an old technique that observes the principles of an MIS procedure. The aim of this study was to provide a step-by-step description from the literature of the Wiltse paraspinal approach and analyze its main advantages and limitations.Methods:Here, we provide a step-by-step description of the Wiltse approach. Utilizing PubMed and Lilacs and the Mesh terms “Wiltse approach,” “paraspinal approach,” “muscle sparing approach,” and “lumbar spine,” we identified 10 papers. We then put together, based on these publications, a step-by-step analysis of the preparation, patient positioning, skin incision, fascial opening, dissection, bone identification, retractors, deperiostization, decompression, discectomy, instrumentation, arthrodesis, and closure for the Wiltse technique.Results:Most papers underscored the minimally invasive aspects of the typical Wiltse approach. Advantages included minimal intraoperative bleeding, a shorter hospital length of stay, and a low infection rate.Conclusion:The classical approach described by Wiltse is essentially minimally invasive, sparing both the muscle planes and soft tissues, allowing for ample far lateral lumbar decompression, including discectomy and fusion, with a low complication rate.

Outcome of Decompression Alone for Foraminal/Extraforaminal Entrapment of L5 Nerve Root Through Wiltse Paraspinal Approach.

Retrospective analysis. The objective of the study was to present the surgical outcome and analyze the prognostic factors for postoperative leg pain after posterior decompression alone for foraminal/extraforaminal L5 entrapment at L5-S1 segment (LSS). Disk extrusion, hypertrophy of facet joint, osteophyte of vertebral body, thickened lumbosacral ligament, and collapsed disk lead to form the lumbosacral tunnel which compresses the L5 exiting nerve root. There are few reports discussing the outcome and prognostic factors of posterior decompression alone. One hundred two consecutive patients underwent posterior decompressive surgery through Wiltse approach for foraminal/extraforaminal entrapment at LSS, performed by 2 surgeons. Demography and preoperative radiograph were analyzed for 6 parameters: age, pathology, disk height, relative disk height ratio, depth of L5 vertebrae within the pelvis, and coronal wedging angle of the segment. Clinical outcomes were assessed by the Visual Analog Scale score for back and leg pain, Oswestry Disability Index, and modified Macnab criteria. The incidence of medications of anticonvulsants, opioids, epidural nerve root block and revisional surgery at index level were also examined. This study included 93 patients. The mean follow-up period was 40.6±19.7 months. Thirty-six patients had disk herniation and 57 had stenosis. Preoperative Visual Analog Scale score and Oswestry Disability Index significantly improved at the final follow-up. On the basis of the modified Macnab criteria, 83% of the patients had good outcomes at follow-up. The mean duration of the medications of anticonvulsants or opioids is 27.2±37.4 days (0-210 d). 5 patients (5.4%) were reoperated. Relative disk height ratio <0.8 was associated with worsening of postoperative leg pain (P<0.01). Decompression as the only method for foraminal/extraforminal lesion of LSS through Wiltse paraspinal approach provided good clinical results. A large difference of disk height between standing and supine positions is associated with poor clinical outcomes.

Microsurgical Foraminotomy via Wiltse Paraspinal Approach for Foraminal or Extraforaminal Stenosis at L5-S1 Level : Risk Factor Analysis for Poor Outcome.

ObjectiveThe purpose of this study was to present the outcome of the microsurgical foraminotomy via Wiltse paraspinal approach for foraminal or extraforaminal (FEF) stenosis at L5–S1 level. We investigated risk factors associated with poor outcome of microsurgical foraminotomy at L5–S1 level.MethodsWe analyzed 21 patients who underwent the microsurgical foraminotomy for FEF stenosis at L5–S1 level. To investigate risk factors associated with poor outcome, patients were classified into two groups (success and failure in foraminotomy). Clinical outcomes were assessed by the visual analogue scale (VAS) scores of back and leg pain and Oswestry disability index (ODI). Radiographic parameters including existence of spondylolisthesis, existence and degree of coronal wedging, disc height, foramen height, segmental lordotic angle (SLA) on neutral and dynamic view, segmental range of motion, and global lumbar lordotic angle were investigated.ResultsPostoperative VAS score and ODI improved after foraminotomy. However, there were 7 patients (33%) who had persistent or recurrent leg pain. SLA on neutral and extension radiographic films were significantly associated with the failure in foraminotomy (p<0.05). Receiver-operating characteristics curve analysis revealed the optimal cut-off values of SLA on neutral and extension radiographic films for predicting failure in foraminotomy were 17.3° and 24°s, respectively.ConclusionMicrosurgical foraminotomy for FEF stenosis at L5–S1 level can provide good clinical outcomes in selected patients. Poor outcomes were associated with large SLA on preoperative neutral (>17.3°) and extension radiographic films (>24°).

Intramedullary screw fixation through Wiltse paraspinal approach to treat thoracolumbar spine fracture

Objective To demonstrate the efficacy of fixation with short-segment thoracolumbar pedicle screws through Wiltse paraspinal approach in treatment of the thoracolumbar spine fracture without neurotrosis. Methods A retrospective analysis was conducted of the 48 patients with thoracolumbar spine fracture who had undergone intramedullary screw fixation from November 2013 to January 2015. The Wiltse paraspinal approach was adopted in 24 patients (group A), 12 males and 12 females, with a mean age of 48.1 ± 8.0 years. The conventional approach was adopted in 24 patients (group B), 19 males and 5 females, with a mean age of 46.7 ± 13.1 years. The 2 groups were compatible in preoperative demographic data (P > 0.05) . Operation time, blood loss,time for ambulation, visual analogue scale (VAS) scores for the waist pain pre- and post-operation, and recovery rates of anterior vertebral height pre-operation, post-operation but pre-ambulation and at the last follow-up were compared between the 2 groups. Results No incision infection or implant failure occurred in either group. The operation time, blood loss and time for ambulation in group A were significantly less than in group B (P 0.05). Conclusion Although intramedullary screw fixation through both approaches can lead to favorable reduction, the Wiltse paraspinal approach can result in shorter operation time, less operative trauma, and quicker recovery. Key words: Spinal fractures; Fracture fixation, internal; Bone nails

Differences in Damage to CGRP Immunoreactive Sensory Nerves After Two Lumbar Surgical Approaches

Immunohistochemical study. To evaluate invasive surgical approaches by analyzing the number of sensory nerve fibers at 2 back muscle sites in rats and humans and the number of injured nerve fibers innervating these 2 sites after muscle injury in rats. SUMMARY OF BACKGROUND DATA.: Several minimally invasive approaches have recently become popular in the treatment of lumbar spine disorders. Minimally invasive surgery (MIS) is not invasive to back muscle and is thought to reduce low back pain. Muscle damage has been generally evaluated by magnetic resonance imaging (MRI); however, damage to sensory nerve fibers in and around back muscle that is directly related to pain has apparently not been explored. Human muscle at L4-L5 was obtained from the paraspinous process (during a midline approach) and from paraspinal back muscle (during a Wiltse paraspinal approach) (n = 10 each). The muscle was sectioned and immunostained for calcitonin gene-related peptide (CGRP). To detect dorsal root ganglion (DRG) neurons innervating back muscle in rats, Fluoro-Gold (FG) was applied to the same 2 sites on the lower back muscle at L4-L5 (only application, n = 12; application of FG + muscle injury, n = 12). DRGs were harvested and immunostained for CGRP and activating transcription factor-3 (ATF-3: marker for nerve injury). The numbers of FG-labeled CGRP-immunoreactive or FG-labeled ATF-3-immunoreactive DRG neurons innervating the 2 sites were counted and compared. CGRP-immunoreactive sensory nerve fibers were found at the 2 sites. The average number of CGRP-immunoreactive sensory nerve fibers in muscle obtained in a midline approach was significantly higher than that in muscle obtained in a Wiltse paraspinal approach (P < 0.01). The numbers of FG-labeled CGRP- and ATF-3-immunoreactive DRG neurons innervating paraspinous process muscle were significantly greater than those innervating paraspinal back muscle in rats (P < 0.01). There are more CGRP-immunoreactive sensory nerve fibers and DRG neurons innervating muscle in the midline approach area than in the Wiltse paraspinal approach area in humans and rats. There are more ATF-3-immunoreactive DRG neurons innervating muscle in the midline approach area than in the Wiltse paraspinal approach area after muscle injury in rats. This result may show the differences in sensory nerve injury during the 2 surgical approaches.

Comparison study between Wiltse paraspinal approach and conventional approach for thoracolumbar vertebral fracture.

Objective To determine the difference of paraspinal muscle injury between Wiltse paraspinal approach and conventional approach for the thoracolumbar vertebral fracture with open reduction and internal fixation. Methods A total of 47 patients with thoracolumbar vertebral fracture(ASIA E) under-went posterior open reduction and internal fixation from June 2004 to December 2006. Randomly, 22 pa-tients adopted Wiltse paraspinal approach, including 16 males and 6 females with the mean age of 37.6 years; 25 patients adopted traditional approach, 18 males and 7 females with the mean age of 40.1 years. The operative duration, blood loss and changes of postoperative serum level of Creatinine Kinase were com-pared. Total 47 patients were followed up with VAS scores 1 day preoperatively, 1 and 6 months postopera-tively. And EMG were adopted for long-term evaluation. Results There was no obvious difference in surgi-cal time, but less blood loss, lower index of serum level of Creatinine Kinase in Wihse paraspinal approach group. The VAS score in Wihse paraspinal approach was significantlt less than that in conventional approach group 1 and 6 months postoperatively. And in conventional approach group EMGs demonstrated fibrillation potentials, but they were normal in Wihse approach group. Conclusion The Wihse paraspinal approach is an easy way for treating of thoracolumbar vertebral fracture, minimize the soft tissue injury in operation and creates less complications after operation. Key words: Thoracic vertebrae; Lumbar vertebrae; Spinal fractures; Fracture fixation, internal

The Wiltse Paraspinal Approach to the Lumbar Spine Revisited

The paraspinal posterior approach to the lumbar spine initially was described for spinal fusion, particularly for treatment of lumbosacral spondylolisthesis. Despite the technical details described by Wiltse et al, the exact location of the sacrospinalis muscle that must be split remains unclear. We sought to clarify the anatomic description of the paraspinal posterior approach to the lumbar spine, and to provide topographic landmarks for facilitating this surgical approach. Fifty cadavers were dissected using an anatomic transmuscular paraspinal approach. The level of the natural cleavage plane between the multifidus and the longissimus parts of the sacrospinalis muscle was noted, and measurements were taken between this level and the midline at the level of the spinous process of L4. A natural cleavage plane between the multifidus and the longissimus parts of the sacrospinalis muscle was present in all specimens. There was a fibrous separation between the two muscular parts in 88 of 100 cases. The mean distance between the level of the cleavage plane and the midline was 4.04 cm (range, 2.4-7 cm). Small arteries and veins were present at the level of the cleavage plane in all specimens. These vascular landmarks make it easier to locate the muscular cleavage plane and reach the articular and transverse processes during the paraspinal approach.