Safety of spinal decompression using an ultrasonic bone curette compared with a high-speed drill: outcomes in 337 patients

The Predictors of Incidental Durotomy in Patients Undergoing Pedicle Subtraction Osteotomy for the Correction of Adult Spinal Deformity

Background: Pedicle subtraction osteotomy (PSO) is a powerful tool for sagittal plane correction in patients with rigid adult spinal deformity (ASD); however, it is associated with high intraoperative blood loss and the increased risk of durotomy. The objective of the present study was to identify intraoperative techniques and baseline patient factors capable of predicting intraoperative durotomy. Methods: A tri-institutional database was retrospectively queried for all patients who underwent PSO for ASD. Data on baseline comorbidities, surgical history, surgeon characteristics and intraoperative maneuvers were gathered. PSO aggressiveness was defined as conventional (Schwab 3 PSO) or an extended PSO (Schwab type 4). The primary outcome of the study was the occurrence of durotomy intraoperatively. Univariable analyses were performed with Mann-Whitney U tests, Chi-squared analyses, and Fisher's exact tests. Statistical significance was defined by p < 0.05. Results: One hundred and sixteen patients were identified (mean age 61.9 ± 12.6 yr; 44.8% male), of whom 51 (44.0%) experienced intraoperative durotomy. There were no significant differences in baseline comorbidities between those who did and did not experience durotomy, with the exception that baseline weight and body mass index were higher in patients who did not suffer durotomy. Prior surgery (OR 2.73; 95% CI [1.13, 6.58]; p = 0.03) and, more specifically, prior decompression at the PSO level (OR 4.23; 95% CI [1.92, 9.34]; p < 0.001) was predictive of durotomy. A comparison of surgeon training showed no statistically significant difference in durotomy rate between fellowship and non-fellowship trained surgeons, or between orthopedic surgeons and neurosurgeons. The PSO level, PSO aggressiveness, the presence of stenosis at the PSO level, nor the surgical instrument used predicted the odds of durotomy occurrence. Those experiencing durotomy had similar hospitalization durations, rates of reoperation and rates of nonroutine discharge. Conclusions: In this large multisite series, a history of prior decompression at the PSO level was associated with a four-fold increase in intraoperative durotomy risk. Notably the use of extended (versus) standard PSO, surgical technique, nor baseline patient characteristics predicted durotomy. Durotomies occurred in 44% of patients and may prolong operative times. Additional prospective investigations are merited.

Ultrasonic Bone Scalpel versus Conventional Technique for Thoracolumbar Spinal Decompression: A Prospective Randomized Controlled Trial

Objective  The purpose of the present study is to compare intraoperative blood loss, operating time, laminectomy time, hospital length of stay, and complications in thoracolumbar spinal decompression using ultrasonic bone scalpels (UBSs) with conventional procedures. Methods  Forty-two patients who underwent decompressive laminectomy and pedicular screw fusion with a surgical level of 1-5 levels between February 1, 2020, and June 30, 2022, in a single institution were evaluated for eligibility, and 11 were excluded due to a history of spinal surgery ( n  = 3), spinal tumor ( n  = 3), and spinal infection ( n  = 5). A total of 31 patients were randomly divided into the UBS group ( n =15) and the conventional group ( n =16). Intraoperative blood loss, operating time, laminectomy time, hospital length of stay, and complications were recorded. Results  Intraoperative blood loss and laminectomy time were significantly lower in the UBS group (656.0 ± 167.6 ml, 54.5 ± 27.4 minutes, respectively) than in the conventional group (936.9 ± 413.2 ml, 73.4 ± 28.1 minutes, respectively). Overall operation time, hospital length of stay, and complications were all similar between the groups. Conclusion  The UBS is a useful instrument for procedures performed near the dura mater or other neural tissue without excessive heat or mechanical injury. This device is recommended for various spinal surgeries in addition to high-speed burrs and Kerrison rongeurs.

Ultrasonic Bone Scalpel versus Conventional Methods for Osteotomy in Posterior Surgery for Cervical Spondylotic Myelopathy: A Review and Meta-Analysis

Posterior methods for cervical myelopathy include laminoplasty and laminectomy with/without fusion. A more recent innovation in these treatments is the use of an ultrasonic bone shaver for osteotomy. In this study, we examined the perioperative results after laminectomy/laminoplasty between conventional methods (rongeur/high-speed drill) vs. piezosurgery-based instruments. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed and the search was performed on four databases (PubMed, Scopus, EMBASE, and Google Scholar). Seven comparative studies were chosen after thorough screening by the authors and a meta-analysis was performed between piezosurgery and conventional technique to ascertain intraoperative and postoperative results after laminectomy/laminoplasty. The analysis includes four retrospective cohort studies and three randomized controlled trials published between 2015 and 2022. The mean age ranged from 55.5 to 64.2 years. Blood loss was significantly reduced in the piezosurgery group, other findings were not significant. On subgroup analysis, laminoplasty dramatically reduced blood loss and the rate of iatrogenic dural rips in the piezosurgery group. The use of ultrasonic bone shaver for osteotomy in cervical spondylotic myelopathy is related to significantly decreased blood loss and no significant increase in postoperative drainage, operative time, complication rate, and functional outcomes as compared to traditional techniques. We noticed significantly reduced blood and rate of dural tears in the laminoplasty subgroup with the use of ultrasonic bone shaver, which was not mirrored in the laminectomy subgroup. Careful intraoperative handling of the instrument can help prevent iatrogenic dural tears and nerve damage.

Improving Surgeon Well-Being: Ergonomics in Neurosurgery

BACKGROUND

Musculoskeletal disorders are common among surgeons, and affect most neurosurgeons over the course of their career. Although all subspecialist neurosurgeons may be affected by physical strain, spine surgeons and skull base surgeons have a high propensity for workplace injury as a result of long procedures with repetitive movements in strained physical positions.

METHODS

In this review, the prevalence of musculoskeletal disorders in neurosurgery, the state of innovation to improve ergonomics in the operating room for neurosurgeons, and potential limitations in advancing technology with the goal of maximizing neurosurgeon longevity are discussed.

RESULTS

Innovations such as robotics, the exoscope, and handheld devices with more degrees of freedom have allowed surgeons to maneuver instruments without exerting excessive effort, all while maintaining neutral body positioning, avoiding joint and muscle strain.

CONCLUSIONS

As new technology and innovation in the operating room develop, there has been a larger emphasis placed on maximizing surgeon comfort and neutral positioning, by minimizing force exertion and fatigue.

Ultrasonic bone scalpel in spine surgery

Background

Spine surgery has always been considered technically demanding even in the hands of the most experienced surgeon on account of close proximity of vital soft tissue structures. Technical advancements over the last few decades have been crucial for the progress of this complex speciality which not only increased the surgical accuracy, but patient safety as well. Ultrasonic devices are one such innovation based on piezoelectric vibrations, patented by Fernando Bianchetti, Domenico Vercellotti, and Tomaso Vercellotti in 1988.

Methods

We did an extensive literature search on ultrasonic devices and their applications in the field of spine surgery.

Results

We present the various ultrasonic bone devices available including their physical, technologic and clinical aspects in spine surgery. We also attempt to cover the limitations and future advances of Ultrasonic bone scalpel (UBS) in particular, which would be interesting and informative for any spine surgeon who is novice in this field.

Conclusion

UBS has been found to be safe and effective in all forms of spine surgeries offering distinct advantages over conventional instruments, although limited by an inherent learning curve.

The Use of Ultrasonic Bone Scalpel (UBS) in Unilateral Biportal Endoscopic Spine Surgery (UBESS): Technical Notes and Outcomes

STUDY DESIGN

Case Series and Technical Note, Objective: UBS has been extensively used in open surgery. However, the use of UBS during UBESS has not been reported in the literature. The aim of this study was to describe a new spinal surgical technique using an ultrasonic bone scalpel (UBS) during unilateral biportal endoscopic spine surgery (UBESS) and to report the preliminary results of this technique.

METHODS

We enrolled patients diagnosed with lumbar spinal stenosis who underwent single-level UBESS. All patients were followed up for more than 12 months. A unilateral laminotomy was performed after bilateral decompression under endoscopy. We used the UBS system after direct visualization of the target for a bone cut. We evaluated the demographic characteristics, diagnosis, operative time, and estimated blood loss of the patients. Clinical outcomes included the visual analog scale (VAS), the Oswestry Disability Index (ODI), the modified MacNab criteria, and postoperative complications.

RESULTS

A total of twenty patients (five males and fifteen females) were enrolled in this study. The mean follow-up period was 13.2 months (range 12-17 months). The VAS score, ODI, and modified MacNab criteria classification improved after the surgery. A minimal mean blood loss of 22.1 mL was noted during the operation. Only one patient experienced neuropraxia, which resolved within 2 weeks. There was no durotomy, iatrogenic pars fracture, or infection.

CONCLUSIONS

In conclusion, our study represents the first report of the use of UBS during UBESS. Our findings demonstrate that this technique is safe and efficient, with improved clinical outcomes and minimal complications. These preliminary results warrant further investigation through larger clinical studies with longer follow-up periods to confirm the effectiveness of this technique in the treatment of lumbar spinal stenosis.

Analysis of the curative effect of cervical spondylotic radiculopathy with osseous foraminal stenosis using ultrasonic osteotome in anterior cervical surgery

PURPOSE

To explore the clinical efficacy and operation points of cervical radiculopathy with osseous foraminal stenosis treated with ultrasonic osteotome in anterior cervical surgery.

METHODS

From January 2018 to June 2021，a retrospective analysis of 23 patients with cervical radiculopathy with bony foraminal stenosis during this period was retrospectively analyzed. Anterior Cervical Discectomy and Fusion (ACDF) was used for all cases in this group. Intraoperative use of ultrasonic osteotome to decompress the nerve in the intervertebral foramina. The operation time, intraoperative blood loss and complication rate were recorded in this group of patients. Interbody fusion was evaluated using Brantigan criteria. The IC-PACS imaging system was used to measure the intervertebral foramen area (IFA) before and after surgery to evaluate the range of decompression. The VAS (Visual Analogue Scale, VAS) score and NDI (Neck Disability Index, NDI) score before and after surgery were recorded to evaluate the clinical efficacy.

RESULTS

All enrolled patients were followed up regularly for 1 year or more. The mean operative time was 61.5 ± 8.0 minutes. The average intraoperative blood loss was 88.3 ± 12.8 ml, and the average hospital stay was 8.1 ± 1.7d. Twenty one cases of successful fusion were followed up 1 year after operation, and the fusion rate was 91.3%. IFA expanded from 25.1 ± 4.0 mm2 before operation to 57.9 ± 3.4 mm2 at 1 year after operation, and the difference was statistically significant (P < 0.001). The VAS score and NDI score of patients 3 days after surgery, 3 months after surgery, and 1 year after surgery were significantly lower than those before surgery (P < 0.001). There was 1 case of dysphagia and 1 case of Cage subsidence after operation, and the complication rate was 8.6%.

CONCLUSION

Anterior cervical surgery using ultrasonic osteotome in the treatment of cervical radiculopathy with bony foraminal stenosis has reliable clinical efficacy and high safety, and is worthy of clinical promotion.

Clinical effect of channel assisted cervical key hole technology combined with ultrasonic bone osteotome in the treatment of single segment cervical spondylotic radiculopathy

OBJECTIVE

To explore the clinical effect and operating skills of channel assisted Cervical Key Hole technology combined with Ultrasonic Bone Osteotome (CKH-UBO) in the treatment of single segment cervical spondylotic radiculopathy (CSR).

METHODS

From June 2018 to June 2020, 14 patients diagnosed with CSR and treated with channel assisted CKH-UBO were collected. The duration of the disease, the length of the incision, the operation time, the amount of bleeding during the operation, the length of hospitalization and the complications were recorded. The Range Of Motion (ROM) and the stability of the surgical segment were recorded before and after the operation. Visual analog scale (VAS), neck disability index (NDI) and modified macnab efficacy evaluation criteria were used to evaluate the surgical efficacy.

RESULTS

The operative segments of the enrolled patients were all lower cervical vertebrae. The average incision length was 2.0 ± 0.1 cm, the operation time was 42.2 ± 5.7 min, the intraoperative bleeding volume was 32.7 ± 4.1 ml, and the hospital stay was 5.6 ± 1.2 days. There was no difference in ROM between preoperative and 3 months and 1 year after operation (P > 0.05), and all patients did not have segmental instability. The VAS scores of neck pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 5.6 ± 1.2, 1.6 ± 0.6, 1.1 ± 0.7, 0.6 ± 0.5, and the VAS scores of upper limb pain were 6.2 ± 1.2, 1.7 ± 0.7, 1.1 ± 0.6, 0.6 ± 0.5. The NDI scores of upper limb pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 36.7 ± 3.5, 9.8 ± 2.4, and 3.9 ± 1.5, 1.8 ± 1.0, The VAS and NDI scores at all follow-up time points after operation were significantly lower than those before operation (P < 0.001). One year after operation, the curative effect was evaluated according to the modified macnab evaluation standard, and the excellent and good rate was 100%. The complication rate was 6.25%.

CONCLUSION

Channel assisted CKH-UBO for single segment CSR has the advantages of short operation time, reliable clinical effect, high safety and low complication rate, which is worthy of clinical promotion.

Ergonomics in Spine Surgery

As physician burnout and wellness become increasingly recognized as vital themes for the medical community to address, the topic of chronic work-related conditions in surgeons must be further evaluated. While improving ergonomics and occupational health have been long emphasized in the executive and business worlds, particularly in relation to company morale and productivity, information within the surgical community remains relatively scarce. Chronic peripheral nerve compression syndromes, hand osteoarthritis, cervicalgia and back pain, as well as other repetitive musculoskeletal ailments affect many spinal surgeons. The use of ergonomic training programs, an operating microscope or exoscope, powered instruments for pedicle screw placement, pneumatic Kerrison punches and ultrasonic osteotomes, as well as utilizing multiple surgeons or microbreaks for larger cases comprise several methods by which spinal surgeons can potentially improve workspace health. As such, it is worthwhile exploring these areas to potentially improve operating room ergonomics and overall surgeon longevity.

Effect of Ultrasonic Osteotome on Therapeutic Efficacy and Safety of Spinal Surgery: A System Review and Meta-Analysis

Background. A meta-analysis was performed to evaluate the effectiveness and safety of ultrasonic osteotomes in spine surgery to standard spinal surgery procedures. Methods. Using the search keywords “bone curette”, “cutter”, “scalpel”, “bone shaver”, “aspirator”, “osteotome”, “ultrasonic”, “piezosurgery”, and “ ${\text{dent}\hspace{0.17em}\hspace{0.17em}}^{\ast }$ ” in the databases of PubMed (1966-2021.12), Cochrane Library, Embase (1986-2018.12), Web of Science (1978-2021.12), and China Academic Journals Full-Text Database (CNKI, 1979-2021.12). Two researchers reviewed the literature, extracted and extensively assessed the data, and included information on the study quality. RevMan v5.3.5.0 was used for the meta-analysis. Results. A total of 10 trials with a total of 911 patients were included. The meta-analysis findings revealed that, when compared to traditional methods, ultrasonic osteotomes could save operation time ( $\text{OR}=-18.83$ , 95 percent CI (-22.76, -14.99), $P=0.03$ ) and reduce intraoperative bleeding ( $\text{OR}=-66.73$ , 95 percent CI (-75.70, -57.76), $P=0.04$ ) and postoperative complications ( $\text{OR}=0.38$ , 95 percent CI (0.21, 0.69), $P=0.001$ ). There was, however, no significant difference in the hospital stay ( $\text{OR}=-1.34$ , 95 percent CI (-1.90, -0.77), $P=0.23$ ) and symptom improvement rate ( $\text{OR}=1.03$ , 95 percent CI (0.73, 1.45), $P=0.86$ ). Conclusion. There is evidence that using an ultrasonic osteotome in spine surgery is safe and effective and may minimize intraoperative bleeding and save time. However, there is no significant difference in symptom improvement rate, hospital stay length, or postoperative complications compared to standard surgical equipment. Therefore, more high-quality investigations are needed to corroborate the initial results.

Spinal decompression with patient-specific guides

BACKGROUND CONTEXT

Patient-specific instruments (PSI) have been well established in spine surgery for pedicle screw placement. However, its utility in spinal decompression surgery is yet to be investigated.

PURPOSE

The purpose of this study was to investigate the feasibility and utility of PSI in spinal decompression surgery compared with conventional freehand (FH) technique for both expert and novice surgeons.

STUDY DESIGN

Human cadaver study.

METHODS

Thirty-two midline decompressions were performed on 4 fresh-frozen human cadavers. An expert spine surgeon and an orthopedic resident (novice) each performed 8 FH and 8 PSI-guided decompressions. Surgical time for each decompression method was measured. Postoperative decompression area, cranial decompression extent in relation to the intervertebral disc, and lateral recess bony overhang were measured on postoperative CT-scans. In the PSI-group, the decompression area and osteotomy accuracy were evaluated.

RESULTS

The surgical time was similar in both techniques, with 07:25 min (PSI) versus 06:53 min (FH) for the expert surgeon and 12:36 min (PSI) vs. 11:54 (FH) for the novice surgeon. The postoperative cranial decompression extent and the lateral recess bony overhang did not differ between both techniques and surgeons. Further, the postoperative decompression area was significantly larger with the PSI than with the FH for the novice surgeon (477 vs. 305 mm²; p=.01), but no significant difference was found between both techniques for the expert surgeon. The execution of the decompression differed from the preoperative plan in the decompression area by 5%, and the osteotomy planes had an accuracy of 1-3 mm.

CONCLUSION

PSI-guided decompression is feasible and accurate with similar procedure time to the standard FH technique in a cadaver model, which warrants further investigation in vivo. In comparison to the FH technique, a more extensive decompression was achieved with PSI in the novice surgeon's hands in this study.

CLINICAL SIGNIFICANCE

The PSI-guided spinal decompression technique may be a useful alternative to FH decompression in certain situations. A special potential of the PSI technique could lie in the technical aid for novice surgeons and in situations with unconventional anatomy or pathologies such as deformity or tumor. This study serves as a starting point toward PSI-guided spinal decompression, but further in vivo investigations are necessary.

Power-Tool Use in Orthopaedic Surgery: Iatrogenic Injury, Its Detection, and Technological Advances: A Systematic Review

Power tools are an integral part of orthopaedic surgery but have the capacity to cause iatrogenic injury. With this systematic review, we aimed to investigate the prevalence of iatrogenic injury due to the use of power tools in orthopaedic surgery and to discuss the current methods that can be used to reduce injury.

Surgical Resection of a Parietal Osteoma in a Domestic Ferret Using Advanced Neurosurgical Techniques

A 3.5 yr old male neutered ferret presented with progressive enlargement of a right dorsocaudal skull mass that had occurred over 18 mo. Computed tomography imaging revealed a large (2.4 × 2.7 cm), well-defined, pedunculated osseous mass arising from the right parietal bone. Cytology was inconclusive, and surgical biopsy was consistent with an osteoma. Further enlargement of the mass occurred over the next 3 mo, at which time surgical intervention was pursued. The patient recovered well, despite the persistence of a bony defect at the former mass site, and no mass regrowth occurred in the 14 mo following the surgical resection. This is one of only two reports in the literature to document the surgical removal of an osteoma in a ferret, and this is the sole case in which a custom apparatus was fabricated for head stabilization, a multiaxis adjustable surgical table was used to improve access to the surgical site, and an ultrasonic scalpel was used for the mass resection.

A comparison of piezo surgery osteotomies with conventional internal osteotomies as performed by trainee surgeons: a cadaveric study

INTRODUCTION

Aesthetic rhinoplasty remains a challenging procedure with high expectations and narrow tolerance for errors. Considerable training is required to achieve controlled and reliable results. Use of the Piezotome is gaining popularity for performing the nasal osteotomies, a key step in rhinoplasty, where it is reported to improve precision and predictability and to keep tissue damage to a minimum. We compare the outcomes of conventional osteotomy techniques to piezosurgery in human cadavers as undertaken by surgical trainees.

MATERIALS AND METHODS

Seven human cadavers were used and a total of 14 osteotomies were performed. Conventional osteotomies and piezosurgery were carried out each on one side of the cadaver. A number of fragments and a blinded assessment of the accuracy of the osteotomy compared with the preprocedure skin markings were carried out by two experienced rhinoplasty surgeons. The Mann-Whitney test for statistical analysis was used.

RESULTS

The mean number of fragments was 1.57 in the piezosurgery osteotomy and 2.14 using conventional osteotomies. Four of seven piezosurgery osteotomies achieved an accuracy within 1mm. The conventional osteotomies as performed by the trainees showed a significant mismatch of more than 3mm in three of seven of cases. Accuracy within 1mm was achieved in one of seven cases.

DISCUSSION

Piezosurgery offers a safe, reliable and precise method of performing lateral nasal osteotomies. This human cadaver study shows a high accuracy of osteotomy and fewer comminuted fractures using this technique compared with conventional osteotomy techniques.

Efficacy and Safety of Ultrasonic Bone Curette-assisted Dome-like Laminoplasty in the Treatment of Cervical Ossification of Longitudinal Ligament

Objective

To assess the efficacy and safety of ultrasonic bone curette‐assisted dome‐like laminoplasty in the treatment of ossification of longitudinal ligament (OPLL) involving C₂.

Methods

A total of 64 patients with OPLL involving C₂ level were enrolled. Thirty‐eight patients who underwent ultrasonic bone curette‐assisted dome‐like laminoplasty were defined as ultrasonic bone curette group (UBC), and 28 patients who underwent traditional high‐speed drill‐assisted dome‐like laminoplasty were defined as high‐speed drill group (HSD). Patient characteristics such as age, sex, body mass index (BMI), symptomatic duration, and other information like the type of OPLL, the time of surgery, blood loss, C₂–C₇ Cobb angle change and complications were all recorded and compared. The Japanese Orthopaedic Association (JOA) score, the nerve root functional improvement rate (IR), and the visual analogue scale (VAS) were used to assess neurological recovery and pain relief. The change of the distance between the apex of ossification and a continuous line connecting the anterior edges of the lamina was measured to assess the spinal expansion extent. The measured data were statistically processed and analyzed using SPSS 21.0 software, and the measurement data were expressed as mean ± SD.

Results

In ultrasonic bone curette (UBC) group and high‐speed drill group (HSD) group, the average time for laminoplasty was 52.3 ± 18.2 min and 76.0 ± 21.8 min and the mean bleeding loss volume was 155.5 ± 41.3 mL and 177.4 ± 54.7 mL, respectively, with a statistically significant difference between the groups. Both groups demonstrated a significant improvement in neurological function. However, the VAS score in UBC group was lower than in HSD group at the 6‐month follow‐up (P < 0.05), but there was no significant difference at 1‐year follow‐up. We found that the loss of lordosis was 1.5° ± 1.0° in UBC group, which is significantly lower than that of HSD group at 1‐year follow‐up (3.8° ± 1.2°, P < 0.05). According to the change of canal dimension, we found that the expansion extent of the spinal canal in UBC group was similar to that of HSD group (P > 0.05). Only one patient in the UBC group and five patients in the HSD group displayed cerebrospinal fluid (CSF) leakag.

Conclusions

With the use of ultrasonic bone curette in OPLL dome‐like decompression, the decompression surgery could be completed relatively safely and quickly. It effectively reduced the amount of intraoperative blood loss and complications, and had better initial recovery of neck pain.

Plunging Dangerously: A Quantitative Assessment of Drilling the Clavicle

Bicortical drilling of the clavicle is associated with risk of iatrogenic damage from plunging given the close proximity of neurovascular structures. This study determined plunge depth during superior-to-inferior clavicle drilling using a standard drill vs drill-sensing technology. Two orthopedic surgeons drilled 10 holes in a fresh cadaveric clavicle with drill-sensing technology in freehand mode (functions as standard orthopedic drill) and another 10 holes with drill-sensing technology in bicortical mode (drill motor stops when the second cortex is breached and depth is measured in real time). The drill-measured depths were compared with computed tomography-measured depths. Distances to the neurovascular structures were also measured. The surgeons' plunge depths were compared using an independent t test. With freehand (standard) drilling, the mean plunge depth was 8.8 mm. For surgeon 1, the range was 5.6 to 15.8 mm (mean, 10.9 mm). For surgeon 2, the range was 3.3 to 11.0 mm (mean, 6.4 mm). The surgeons' plunge depths were significantly different. In bicortical mode, the drill motor stopped when the second cortex was penetrated. Drill-measured depths were verified by computed tomography scan, with a mean difference of 0.8 mm. Mean distances from the clavicle to the neurovascular structures were 15.5 mm for the subclavian vein, 18.0 mm for the subclavian artery, and 8.0 mm for the brachial plexus. Plunge depths differed between surgeons. However, both surgeons' plunge depths were greater than distances to the neurovascular structures, indicating a risk of injury due to plunging. Although a nonspinning drill bit may still cause soft tissue damage, drill-sensing technology may decrease the risk of penetrating soft tissue structures due to plunging. [Orthopedics. 2021;44(1):e36-e42.].

Resection of Spinal Meningioma Using Ultrasonic BoneScalpel Microshaver: Cases, Technique, and Review of the Literature

BACKGROUND

Meningiomas of the spinal canal comprise up to 40% of all spinal tumors. The standard management of these tumors is gross total resection. The outcome and extent of resection depends on location, size, patient's neurologic status, and experience of the surgeon. Heavily calcified spinal meningiomas often pose a challenge for achieving gross total resection without cord injury.

OBJECTIVE

To report our experience with the BoneScalpel Micro-shaver to resect heavily calcified areas of spinal meningiomas adherent to the spinal cord without significant cord manipulation, achieving gross total resection and outstanding clinical results.

METHODS

Seventy-nine and 82-yr-old females presented with progressive leg weakness, paresthesias, and gait instability. Magnetic resonance imaging of the thoracic spine showed a homogenous enhancing intradural extramedullary mass with mass effect on the spinal cord. Midline bilateral laminectomy was performed, and the dura was open in midline. The lateral portion of the tumor away from the spinal cord was resected with Cavitron Ultrasonic Surgical Aspirator while the BoneScalpel Micro-shaver (power level 5 and 30% irrigation) was brought into the field for the calcified portion of the tumor adherent to the spinal cord.

RESULTS

Gross total resection was achieved for both cases. At the 2-wk postoperative visit, both patients reported complete recovery of their leg weakness with significant improvement in paresthesias and ataxia.

CONCLUSION

The ultrasonic osteotome equipped with a microhook tip appears to be a safe surgical instrument allowing for effective resection of spinal meningiomas or other heavily calcified spinal masses not easily removed by usual surgical instrumentation.

Primary lumbar decompression using ultrasonic bone curette compared to conventional technique

PURPOSE

The ultrasonic bone curette (Bone Scalpel) is a novel technique in neurosurgery for bony dissection. This study aimed to evaluate its use against conventional techniques for primary lumbar decompression.

MATERIALS AND METHODS

This study was a retrospective cohort comparison, using Spine Tango Registry data. All patients undergoing a primary procedure for lumbar decompression secondary to degenerative disease during a 2-year period (2014-2016) were identified, split into age and gender matched cohorts utilising either bone scalpel or conventional techniques intra-operatively.

RESULTS

Ninety-three patients were identified within each cohort, which did not differ significantly in terms of age, gender, BMI, number of operative vertebral levels or seniority of the principal surgeon. The incidence of intra-operative blood loss >100 ml was significantly reduced within the bone scalpel cohort (16.1% bone scalpel, 34.4% conventional, p = 0.04). There was no difference in the incidence of iatrogenic dural breach (9.7% bone scalpel, 16.1% conventional, p = 0.27). There was no significant difference in pre-operative Core Outcomes Measures Index (COMI) between the cohorts (7.91 bone scalpel, 8.02 conventional, p = 0.67) and both cohorts demonstrated a significant reduction in mean COMI at 24 months (bone scalpel p = 0.004, conventional p = <0.001). No difference in mean COMI existed between either cohort at any point across the 24-month post-operative period (p = 0.18).

CONCLUSIONS

The use of ultrasonic bone curette for primary lumbar decompression is associated with reduced intra-operative blood loss compared to conventional techniques, alongside a comparable safety profile and equivalent patient reported outcomes.

The Effectiveness and Safety of Ultrasonic Bone Scalpel Versus Conventional Method in Cervical Laminectomy: A Retrospective Study of 311 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The aim of this study was to compare the results of cervical laminectomy (CL) performed with ultrasonic bone scalpel (UBS) or conventional method (CM).

METHOD

This study comprised 311 CL performed by a single surgeon between January 2004 and December 2017. Group A (GpA) comprised 124 cases of CL performed using UBS, while Group B (GpB) comprised 187 cases of CL performed using CM. These 2 groups were compared in terms of demographic characteristics of patients, duration of surgery, estimated blood loss, and surgical complications.

RESULTS

GpA included 112 males and 12 females, mean age being 61.18 years. GpB comprised 166 males and 21 females, mean age being 62.04 years. Mean duration of surgery, estimated blood loss, and length of hospital stay was 65.52/70.87 minutes, 90.24/98.40 mL, and 4.80/4.87 days in GpA and GpB, respectively. Six patients were reported to have dural injuries in each group. In GpA, 2 cases of C5 palsy and 1 nerve root injury was observed, while in GpB, 3 cases of C5 palsy and no nerve root injury was reported. One patient had developed transient neurological deterioration postsurgery in GpA as against 11 patients in GpB.

CONCLUSION

Neurological complications observed in CM leads to intensive care unit admission, additional morbidity, and additional expenditure, whereas UBS provides a safe, rapid, and effective means of performing CL, thereby decreasing the rate of surgical complications and postoperative morbidity.

Ultrasonic osteotome versus high-speed burr in cervical anterior vertebral subtotal resection: A retrospective study of 81 cases

AIM

This study aimed to investigate the safety and effectiveness of ultrasonic osteotome in cervical anterior vertebral subtotal resection.

METHODS

Retrospective clinical data were collated for 81 patients with cervical spondylotic myelopathy who required cervical anterior vertebral subtotal resection.

RESULTS

Group A (n=40) was treated with an ultrasonic osteotome and group B (n=41) with a high-speed burr. Vertebrectomy time, intraoperative blood loss, surgical complications, Japanese Orthopedic Association (JOA) scores and JOA score improvement were compared. Group A showed significantly shorter vertebrectomy time and significantly less intraoperative blood loss (P<0.05). In group A, dysphagia occurred in one patient, and superior laryngeal nerve injury in one. Urinary tract infection occurred in one patient in group B. JOA score in both groups significantly increased 3 days after surgery (P<0.05), and at last follow-up compared with 3 days after surgery (P<0.05).

CONCLUSION

Ultrasonic osteotome was a safe and effective tool for subtotal anterior cervical vertebral resection.

How I do it: en-bloc subaxial cervical laminectomy using a high-speed drill with a footplate attachment

BACKGROUND

Cervical laminectomy is a common strategy to decompress the spinal canal.

METHODS

The anatomy of the cervical spine and surrounding critical structures as viewed from the posterior approach is described. The use of a high-speed drill with a footplate attachment to make laminar troughs with an en-bloc subaxial cervical laminectomy is described with a discussion on surgical technique and complication avoidance.

CONCLUSION

This technique allows for a safe, comfortable, and rapid decompression of the cervical spine with minimal risk. For routine cases, this may potentially be more safe and cost-effective than using a cutting bur or bone scalpel attachment.

Effects of Combined Use of Ultrasonic Bone Scalpel and Hemostatic Matrix on Perioperative Blood Loss and Surgical Duration in Degenerative Thoracolumbar Spine Surgery

How to decrease intraoperative bleeding, shorten surgical time, and increase safety in spinal surgery is an important issue. Ultrasonic bone removers and FloSeal have been proven to increase safety, reduce the surgical duration, and decrease intraoperative bleeding in skull base surgery. Therefore, we aimed to compare the surgical duration, blood loss, and complications during spinal surgery with or without the use of FloSeal and an ultrasonic bone scalpel. Therefore, we retrospectively reviewed 293 patients who underwent thoracolumbar spinal surgery with decompression and instrumented fusion performed by a single surgeon. We divided these patients into three groups, including nonuse of FloSeal nor a bone scalpel (group A), use of FloSeal only (group B), and use of FloSeal and a bone scalpel (group C) intraoperatively after pairing in terms of age, sex, and surgical level. The surgical duration, blood loss, and occurrence of complications were all recorded. The mean surgical duration in group A was 160 mins, in group B it was 167 mins, and in group C it was 134 mins. The mean blood loss was 700 ml in group A, 682 ml in group B, and 383 ml in group C. Six patients sustained intraoperative dura injuries in total, 3 in group A, 2 in group B, and 1 in group C. No postoperative neurologic defects or occurrences of hematoma were recorded. According to our results, we concluded that combined use of FloSeal and bone scalpels is recommended during primary thoracolumbar spinal surgery to reduce the intraoperative blood loss and shorten the surgical duration.

Cerebrospinal fluid leaks after spine tumor resection: avoidance, recognition and management

Post-operative CSF leaks are a known complication of spine surgery in general, and patients undergoing surgical intervention for spinal tumors may be particularly predisposed due to the presence of intradural tumor and a number of other factors. Post-operative CSF leaks increase morbidity, lengthen hospital stays, prolong immobilization and subject patients to a number of associated complications. Intraoperative identification of unintended durotomies and effective primary repair of dural defects is an important first step in the prevention of post-operative CSF leaks, but in patients who develop post-operative pseudomeningoceles, durocutaneous fistulae or other CSF-leak-related sequelae, early recognition and secondary intervention are paramount to preventing further CSF-leak-related complications and achieving the best patient outcomes possible. In this article, the incidence, risk factors and complications of CSF leaks after spine tumor surgery are reviewed, with an emphasis on avoidance of post-operative CSF leaks, early post-operative identification and effective secondary intervention.

Three-dimensional navigation (O-arm) versus fluoroscopy in the treatment of thoracic spinal stenosis with ultrasonic bone curette: A retrospective comparative study

Three-dimensional intraoperative navigation (O-arm) has been used for many years in spinal surgeries and has significantly improved its precision and safety. This retrospective study compared the efficacy and safety of spinal cord decompression surgeries performed with O-arm navigation and fluoroscopy. The clinical data of 56 patients with thoracic spinal stenosis treated from March 2015 to April 2017 were retrospectively analyzed. Spinal decompression was performed with O-arm navigation and ultrasonic bone curette in 29 patients, and with ultrasonic bone curette and fluoroscopy in 27 patients. Patients were followed-up at postoperative 1 month, 3 months, and the last clinic visit. The neurologic functions were assessed using the Japanese Orthopaedic Association (JOA) Back Pain Evaluation Questionnaire. The accuracy of screw placement was examined using three-dimensional computed tomography (CT) on postoperative day 5. There was no significant difference in the incidences of intraoperative dural tear, nerve root injury, and spinal cord injury between the two groups. The two groups showed no significant difference in postoperative JOA scores (P > .05). The O-arm navigation group had significantly higher screw placement accuracy than the fluoroscopy group (P < .05). O-arm navigation is superior to fluoroscopy in the treatment of thoracic spinal stenosis with ultrasonic bone curette in terms of screw placement accuracy. However, the two surgical modes have similar rates of intraoperative complications and postoperative neurologic functions.

Ultrasonic bone scalpel: utility in cervical corpectomy. A technical note

PURPOSE

Anterior cervical corpectomy and fusion (ACCF) is a technically challenging surgery. Use of conventional instruments like high-speed burr and kerrison rongeurs is associated with high complication rates such as increased blood loss and incidental durotomy. Use of ultrasonic bone scalpel (UBS) in cervical corpectomy helps to minimize such adverse events.

METHODS

We performed a retrospective study based on the data of 101 consecutive patients who underwent cervical corpectomies with UBS for different cervical spine pathologies from December 2014 to December 2016. Total duration of surgery, time taken for corpectomy, estimated blood loss, and incidental durotomies were noted.

RESULTS

Total surgical time was 30-80 min (59.36 ± 13.21 min) for single-level ACCF and 60-120 min (92.74 ± 21.04 min) for double-level ACCF. Time taken for single-level corpectomy was 2 min 11  ± 10 s and 3 min 41  ± 20 s for double-level corpectomy. Estimated blood loss ranged from 20-150 ml (52.07 ± 29.86 ml) in single level and 40-200 ml (73.22 ± 41.64 ml) in double level. Four (3.96%) inadvertent dural tears were noted, two during single-level corpectomy and other two during double-level corpectomy.

CONCLUSIONS

Use of UBS is likely to provide a safe, rapid, and effective surgery when compared to conventional rongeurs and high-speed burr. The advantages such as lower blood loss and lower intra-operative incidental dural tears were noted with the use of UBS.

Use of image-guided bone scalpel for resection of spine tumors: technical note

In the literature, the use of navigation for spine tumor surgery has largely centered on implant placement. We describe the cases of two patients with spinal tumors on whom we utilized our resection technique of registering an ultrasonic bone scalpel (UBS) to a navigation system. In both cases, we achieved a satisfactory tumor resection with negative margins and excellent neurologic outcomes. We feel that using the navigation-registered UBS is a valuable tool to increase the operator's ability to achieve desired resections while minimizing the neurologic deficits and operative morbidity associated with these challenging surgical cases.

[Safety and effectiveness of ultrasonic osteotome in posterior cervical laminectomy decompression and fusion]

Objective

To explore the safety of ultrasonic osteotome used in posterior cervical laminectomy decompression surgery and its effect on surgical outcome.

Methods

A clinical data of 52 patients with ossification of posterior longitudinal ligament of cervical spine (C-OPLL) undergoing posterior cervical laminectomy decompression and fusion (PCLDF) between April 2013 and April 2017 was retrospectively analysed. The patients were divided into two groups according to whether using the ultrasonic osteotome during operation: group A (20 cases, ultrasonic osteotome group) and group B (32 cases, traditional gun-clamp decompression group). There was no significant difference in gender, age, body weight, height, preoperative hemoglobin, and Japanese Orthopedic Association (JOA) score between the two groups ( P>0.05). The operation time, intraoperative blood loss, postoperative drainage volume, hospitalization time, complications, hemoglobin at 1 day after operation, and JOA score at 6 months after operation were recorded and compared between the two groups, and the improvement rate of JOA was calculated.

Results

The operation time and intraoperative blood loss in group A were significantly less than those in group B ( P<0.05); there was no significant difference in the drainage volume and hospitalization time between the two groups ( P>0.05). The hemoglobin of group B was slightly higher than that of group A at 1 day after operation, but there was no significant difference between the two groups ( t=-1.260, P=0.214). All the patients were followed up 6-10 months (mean, 7.6 months). No serious complications such as C ₅ nerve paralysis, dural tear, infection, epidural hematoma, deep venous thrombosis, pulmonary embolism, transfusion allergy, or shock occurred during and after operation. The JOA scores of the two groups were significant improved at 6 months after operation when compared with preoperative scores ( P<0.05), and there was no significant difference in JOA score and improvement rate between the two groups at 6 months after operation ( P>0.05).

Conclusion

Compared with the traditional gun-clamp decompression, the effectiveness of PCLDF in treatment of C-OPLL by using ultrasonic osteotome is comparable, but the latter can effectively reduce the operation time and blood loss.

Suitability of Administrative Databases for Durotomy Incidence Assessment: Comparison to the Incidence Associated With Bone-Removal Devices, Calculated Using a Systemic Literature Review and Clinical Data

Background

Durotomy is a major complication of spinal surgery, potentially leading to additional clinical complications, longer hospitalization, and increased costs. A reference durotomy incidence rate is useful for the evaluation of the safety of different surgical aspects. However, the literature offers a wide range of incidence rates, complicating this comparison. Theoretically, a reference incidence value can be extracted from administrative databases, containing a large number of procedures. However, it is suspected that these databases suffer from underreporting of complications. This study aims to evaluate durotomy incidence using several large-scale databases and to assess the ability to use it as a reference by comparison to durotomy incidences directly associated with 4 bone removal devices, including the commonly used high-speed drill.

Methods

Durotomy overall incidence was estimated from several administrative databases using different methods in order to achieve minimal and maximal estimations. Durotomy incidences for 3 bone removal devices were derived using literature meta-analysis, and the incidence for the fourth device was calculated using clinical data.

Results

The incidence range of durotomy according to the databases was 2.8-3.5%. The calculated incidence of durotomy for the studied devices was 0.4-2.91%. The highest rate, 2.91%, is associated with the commonly used high-speed drill combined with Kerrison Rongeur and bone punches. Since bone-removal devices are just one of the possible causes of dural tears, the general incidence is expected to be higher than the incidence associated with the devices, yet even the maximal estimation, 3.5%, was only slightly higher, suggesting that the speculation of underreporting of dural tears to these databases is probably true, as also supported by the mostly higher incidences reported in the literature.

Conclusions

Hospital administrative databases seem to show a lower-than-reasonable incidence of durotomy, suggesting possible underreporting. Researchers should therefore use this tool with caution. Reduction of the absolute durotomy incidence by approximately 2.5% can be achieved by improving the safety of bone-removal devices.

Microendoscopic Surgery with an Ultrasonic Bone Curette for a Patient with Intraforaminal Stenosis of the Lumbar Spine Due to an Ossification Lesion: A Technical Case Report

Introduction:

We present a rare case with radiculopathy resulting from intraforaminal stenosis of the lumbar spine due to an ossification lesion. Microendoscopic surgery was chosen because of two strong advantages. One was the ease to reach the nerve foramen and ossification lesion and the other was the non-invasiveness at the posterior supporting structures of the spine. Moreover, an ultrasonic bone curette developed for microendoscopic spine surgery was applied. This is the first detailed case report of microendoscopic surgery using an ultrasonic bone curette for a patient with radiculopathy due to intraforaminal free ossification.

Case Report:

A 49-year-old woman born in Japan had complained of severe left leg pain for over 7 months in spite of conservative treatment including selective nerve root block. There was no lumbago, muscle weakness, or loss of sensation in her leg. Plain radiography revealed spondylolytic spondylolisthesis classified as Grade II at L4-L5, but there was no instability on dynamic assessment. Computed tomography (CT) showed a free ossification lesion in the foramen at L4-L5. Considering a diagnosis of left L4 radiculopathy due to the free ossification, ossification resection and nerve decompression were performed with posterior spinal microendoscopic surgery using an ultrasonic bone curette. A tubular retractor was introduced into the extraforaminal zone using Wiltse approach. After a part of the ossification lesion and the nerve root were exposed, an ultrasonic bone curette was applied to remove the ossification mass. After decompression, the nerve root was found to be relaxed. The surgical time was 83 min, and blood loss was 5 g. According to the Japanese Orthopedic Association scoring system, her score improved from 21/29 preoperatively to 29/29 postoperatively, and the full score was maintained at the final observation. Post-operative CT revealed the absence of an ossification lesion.

Conclusions:

For a rare case with radiculopathy resulting from intraforaminal stenosis of the lumbar spine due to an ossification lesion, microendoscopic surgery with an ultrasonic bone curette was very effective. The use of ultrasonic bone curette is easy and safe in microendoscopic surgery and it helps achieve less invasiveness and ideal decompression, without injuring the nerve root.

[Application of ultrasonic bone curette in posterior cervical single open-door laminoplasty]

Objective

To investigate the safety and reliability of ultrasonic bone curette in posterior cervical single open-door laminoplasty.

Methods

The clinical data were retrospectively analyzed, from 193 patients who underwent single open-door laminoplasty (C 3-7) from January 2012 to January 2016. The patients were divided into three groups according to different instruments: posterior single open-door laminoplasty was performed with ultrasonic bone curette in 61 cases (group A), with bite forceps in 73 cases (group B), and with micro-grinding drill in 59 cases (group C). There was no significant difference in gender, age, the course of disease, underlying disease and preoperative Japanese Orthopedic Association (JOA) score, visual analogue scale (VAS) between groups ( P>0.05). The operative time, intraoperative blood loss, drainage volume at 48 hours, JOA score, improvement rate, VAS and perioperative com-plication were compared.

Results

The operative time, intraoperative blood loss, and drainage volume at 48 hours of group A were significantly less than those in groups B and C ( P<0.05), but there was no significant between groups B and C ( P>0.05). The follow-up time was 12-21 months (mean, 14.6 months) in group A, 24-36 months (mean, 27.5 months) in group B, and 28-47 months (mean, 38.1 months) in group C. There were no cerebrospinal fluid leakage and incision infection in three groups. No complications of internal fixation loosening and rupture occurred during the follow-up. Rediating pain occurred in 6 cases of group A, 8 cases of group B, and 6 cases of group C, and was cured at 1 week after dehydration and physical therapy. No nerve root palsy was found in three groups. Fracture of portal axis occurred in 5 cases (7 segments) of group B and was fixed by micro titanium plate. The JOA score and VAS score at last follow-up were significantly improved when compared with preoperative scores in three groups ( P<0.05); there was no significant difference in JOA score and improvement rate and VAS score between groups ( P>0.05).

Conclusion

It is safe and reliable to use the ultrasonic bone curette in posterior cervical single open-door laminoplasty. It can shorten the operative time and has similar clinical curative effect to the traditional operation, and the lateral rotation of the lamina can be avoided.

Anterior submandibular retropharyngeal odontoid osteotomy and posterior atlantoaxial fusion for irreducible atlantoaxial dislocation associated with odontoid fracture malunion

PURPOSE

To report a case of complex odontoid fracture malunion accompanied by atlantoaxial dislocation which was treated with a new surgical approach.

METHODS

A 53-year-old female was admitted due to progressive symptoms with a stiff limp and unsteady gait. Preoperative examination, diagnostic radiography, computed tomography, and magnetic resonance imaging were performed following admission. The examinations showed odontoid fracture malunion, an old right axial zygapophyseal fracture, atlantoaxial dislocation, and spinal cord injury. Anterior submandibular retropharyngeal odontoid osteotomy and posterior atlantoaxial fusion were then performed.

RESULTS

Good reduction of the atlantoaxial dislocation was gained. The cervical spinal cord compression was significantly relieved and neurological function was also significantly improved.

CONCLUSION

Anterior submandibular retropharyngeal odontoid osteotomy and posterior atlantoaxial fusion fixation is an effective method for treating IAAD associated with odontoid fracture malunion, it avoids the adverse effects of anterior transoral odontoid osteotomy and provides a new option for the treatment of odontoid fracture malunion associated with atlantoaxial dislocation.

Piezoelectric technology in otolaryngology, and head and neck surgery: a review

BACKGROUND

Piezoelectric technology has existed for many years as a surgical tool for precise removal of soft tissue and bone. The existing literature regarding its use specifically for otolaryngology, and head and neck surgery was reviewed.

METHODS

The databases Medline, the Cochrane Central Register of Controlled Trials, PubMed, Embase and Cambridge Scientific Abstracts were searched. Studies were selected and reviewed based on relevance.

RESULTS

Sixty studies were identified and examined for evidence of benefits and disadvantages of piezoelectric surgery and its application in otolaryngology. The technique was compared with traditional surgical methods, in terms of intra-operative bleeding, histology, learning curve, operative time and post-operative pain.

CONCLUSION

Piezoelectric technology has been successfully employed, particularly in otology and skull base surgery, where its specific advantages versus traditional drills include a lack of 'blunting' and tissue selectivity. Technical advantages include ease of use, a short learning curve and improved visibility. Its higher cost warrants consideration given that clinically significant improvements in operative time and morbidity have not yet been proven. Further studies may define the evolving role of piezoelectric surgery in otolaryngology, and head and neck surgery.

Technical Aspects on the Use of Ultrasonic Bone Shaver in Spine Surgery: Experience in 307 Patients

Aim. We discuss technical points, the safety, and efficacy of ultrasonic bone shaver in various spinal surgeries within our own series. Methods. Between June 2010 and January 2014, 307 patients with various spinal diseases were operated on with the use of an ultrasonic bone curette with microhook shaver (UBShaver). Patients' data were recorded and analyzed retrospectively. The technique for the use of the device is described for each spine surgery procedure. Results. Among the 307 patients, 33 (10.7%) cases had cervical disorder, 17 (5.5%) thoracic disorder, 3 (0.9%) foramen magnum disorder, and 254 (82.7%) lumbar disorders. Various surgical techniques were performed either assisted or alone by UBShaver. The duration of the operations and the need for blood replacement were relatively low. The one-year follow-up with Neck Disability Index (NDI) and Oswestry Disability Index (ODI) scores were improved. We had 5 cases of dural tears (1.6%) in patients with lumbar spinal disease. No neurological deficit was found in any patients. Conclusion. We recommend this device as an assistant tool in various spine surgeries and as a primary tool in foraminotomies. It is a safe device in spine surgery with very low complication rate.

Ultrasonic total uncinectomy: a novel technique for complete anterior decompression of cervical nerve roots

BACKGROUND

In standard anterior cervical diskectomy, complete resection of the uncinate process is not commonly attempted because of the risk of injury to the vertebral artery. This may result in incomplete decompression of the nerve root when there is severe osseous foraminal stenosis.

OBJECTIVE

To demonstrate the feasibility of total uncinectomy with an ultrasonic bone dissector in patients with concomitant central and foraminal stenosis requiring anterior decompression and fusion.

METHODS

A case series of patients with cervical radiculopathy or myeloradiculopathy who underwent single-level or multilevel ultrasonic total uncinectomy (UTU) in combination with anterior cervical diskectomy and fusion is presented. The uncinate process was amputated along its base with an ultrasonic bone dissector and removed en bloc to expose the cervical root and the vertebral artery. Data gathered in accordance with routine practice were analyzed retrospectively.

RESULTS

Forty-four uncinate processes were resected in 38 patients. No UTU procedures were aborted because of technical difficulties, and no vertebral artery or nerve root injury occurred. Mean follow-up was 28 weeks (range, 14-37 weeks). Mean Neck Disability Index and Visual Analog Scale scores for neck and arm pain improved from 42%, 4.9%, and 6.8% to 23%, 2.6%, and 2.1%, respectively. Postoperative computed tomography and oblique radiographs revealed complete decompression of the neural foramen after UTU.

CONCLUSION

UTU is a safe and effective technique for complete decompression of cervical nerve roots when the coexistence of central and foraminal pathology dictates an anterior approach. The surgical technique is described in detail.

Spinal decompression in achondroplastic patients using high-speed drill versus ultrasonic bone curette: technical note and outcomes in 30 cases

BACKGROUND

This manuscript describes the clinical and operative characteristics of achondroplastic children who undergo multilevel thoracolumbar decompressions using either the high-speed drill or the ultrasonic bone curette (BoneScalpel).

METHODS

We retrospectively reviewed 30 thoracolumbar decompressions in achondroplastic patients at a single institution between 2008 and 2013. Patients were classified into either the high-speed drill cohort or the BoneScalpel cohort, depending on which instrument was utilized to perform the decompression. A technical note on the role of the ultrasonic bone curette in decompressing stenotic achondroplastic spines is also provided.

RESULTS

In comparison with the high-speed drill cohort, the BoneScalpel cohort experienced less overall perioperative complications, including durotomy, cerebrospinal fluid leak, pseudomeningoceles, wound infection, and wound dehiscence. Although 45.0% of patients experienced a durotomy in the high-speed drill cohort, only 30.0% of patients experienced a durotomy in the BoneScalpel cohort (P = 0.694). In the high-speed drill cohort, the number of patients complaining of sensory disturbances, back pain, ataxia, incontinence, neurogenic claudication, radiculopathy, ataxia, and/or weakness decreased postoperatively. Similar results were observed in the BoneScalpel cohort.

CONCLUSIONS

Although spinal decompression provides symptomatic resolution in patients with achondroplasia, intraoperative complications, in general, and durotomies, in particular, are common. Here, we report a decreased incidence in intraoperative durotomy and overall perioperative complication rates in the BoneScalpel cohort, although this did not reach the level of statistical significance. Nonetheless, the data demonstrate that the BoneScalpel is a safe and efficacious alternative to the high-speed drill in these challenging patients.

LEVEL OF EVIDENCE

Level II-retrospective study.

Spontaneous regression of sequestrated lumbar disc herniations: Literature review

Lumbar disc herniations (LDH) may regress with conservative management; however, this phenomenon is poorly understood for the sequestrated subtype of LDH. We present one of the first comprehensive literature reviews specifically addressing the spontaneous regression of sequestrated intervertebral discs. We reviewed all publications with lumbar disc herniations, sequestrated subtype. Our results were then narrowed to patients who experienced spontaneous regression of the sequestration. Based on our literature review of 53 cases, patients with sequestrated lumbar disc herniations experienced symptomatic resolution in a mean of 1.33±1.34 months and radiographic resolution in 9.27±13.32 months. Symptomatic patients with sequestrated discs present similarly to those with other types of lumbar disc herniations. Sequestrations may have the highest likelihood to radiographically regress in the shortest time frame in comparison to the remaining subtypes of LDH. The most likely mechanism for regression is an inflammatory response elicited against the free fragment. Patients with disc sequestrations may be managed conservatively, in the absence of intractable pain, inability to walk, weakness or symptoms suggestive of cauda equina syndrome.