Technical advantages of an ultrasonic bone curette in spinal surgery

Application of Piezosurgery in Revision Surgery through Posterior Approach for Infection after Percutaneous Vertebral Augmentation: Technique Note with Case Series

OBJECTIVES

Pyogenic spondylitis after vertebral augmentation (PSVA) is a severe complication and even threatens the life of patients. How to deal with infectious bone cement is a big problem for surgeons. The application of piezosurgery has advantages in removal the infectious bone cement in limb bone and spinal laminectomy, but it is rarely used in PSVA. So, the present study aimed to introduce the application of piezosurgery in revision surgery for PSVA and report the preliminary radiological and clinical results.

METHODS

The data of nine patients with PSVA who had undergone revision surgery were retrospectively reviewed between May 2017 and January 2023 in our hospital. The technique of removal of infectious bone cement and lesion by piezosurgery and the reconstruction of the spinal stability were described, and the operation time and intraoperative blood loss were recorded. Postoperatively, radiographs and computed tomography scans were reviewed to evaluate the condition of bone cement removal, control of infection, and bone fusion. Oswestry disability index (ODI) and visual analog scale (VAS) were assessed pre- and postoperatively, and clinical outcomes were assessed using Odom's criteria.

RESULTS

All patients achieved satisfactory tainted bone cement cleaning and restoration of spinal alignment. The surgical time was 258.8 ± 63.2 (160-360) min, and the intraoperative blood loss was 613.3 ± 223.8 (300-900) mL. The VAS score decreased from 7.0 (6-8) points preoperatively to 2.4 (1-4) points postoperatively. The ODI index decreased from 71% (65%-80%) preoperatively to 20% (10%-30%) postoperatively. The patient's VAS and NDI scores after operation were significantly improved compared with those before surgery (p ≤ 0.05). Odom's outcomes were good for all patients in the last follow-up, and all patients reported satisfactory results.

CONCLUSIONS

Piezosurgery can effectively remove large blocks of infectious bone cement through a posterior approach while avoiding nerve and spinal cord damage. We cautiously suggest that a one-stage posterior approach using piezosurgery is an alternative option for surgical treatment of PSVA.

The Ultrasonic Bone Scalpel does not Outperform the High-Speed Drill: A Single Academic Experience

BACKGROUND

Spinal decompression and osteotomies are conventionally performed using high-speed drills (HSDs) and rongeurs. The ultrasonic bone scalpel (UBS) is a tissue-specific osteotome that preferentially cuts bone while sparing the surrounding soft tissues. There is ongoing investigation into its ability to optimize peri- and postoperative outcomes in spine surgery. The purpose of this study was to compare the intraoperative metrics and complications during a transition period from HSD to UBS.

METHODS

A single-institution, single-surgeon retrospective analysis was conducted of patients undergoing spine surgery from January 2020 to December 2021. Statistical analyses were performed to detect associations between the surgical technique and outcomes of interest. A P value < 0.05 was considered statistically significant.

RESULTS

A total of 193 patients met the inclusion criteria (HSD, n = 100; UBS, n = 93). Multivariate logistic regression revealed similar durotomy (P = 0.10), nerve injury (P = 0.20), and reoperation (P = 0.68) rates. Although the estimated blood loss (EBL) and length of stay were similar, the operative time was significantly longer with the UBS (192.81 vs. 204.72 minutes; P = 0.03). Each subsequent surgery using the UBS revealed a 3.1% decrease in the probability of nerve injury (P = 0.026) but had no significant effects on the operative time, EBL, or probability of durotomy or reoperation.

CONCLUSIONS

The UBS achieves outcomes on par with conventional tools, with a trend toward a lower incidence of neurologic injury. The expected reductions in EBL and durotomy were not realized in our cohort, perhaps because of a high proportion of revision surgeries, although these might be dependent on surgeon familiarity, among other operative factors. Future prospective studies are needed to validate our results and further refine the optimal application of this device in spine surgery.

Channel-assisted cervical key hole technology combined with ultrasonic bone osteotome versus posterior percutaneous endoscopic cervical foraminotomy: a clinical retrospective study

PURPOSE

The search for more effective and safe treatment methods for cervical spondylotic radiculopathy (CSR) has led to the rapid development and increasing popularity of minimally invasive posterior cervical foraminotomy (MI-PCF). This study aims to compare two important approaches for MI-PCF surgery: the channel-assisted cervical key hole technology combined with ultrasonic bone osteotome (CKH-UBO) and posterior percutaneous endoscopic cervical foraminotomy (PPECF).

METHODS

Data from patients treated with single-level CKH-UBO (n = 35) or PPECF (n = 40) were analyzed. Clinical outcomes, including visual analogue scale (VAS) scores for neck and arm pain, Neck Disability Index (NDI), and modified Macnab criteria, were assessed preoperatively, as well as at three days, three months, and one year postoperatively.

RESULTS

The percentages of patients with excellent and good outcomes were 97.14% and 92.5%, respectively. The average surgical time in the CKH-UBO group was significantly shorter than in the PPECF group (p < 0.001), while the average incision length in the PPECF group was significantly smaller than in the CKH-UBO group. There were no significant differences between the two groups in terms of blood loss, hospital stay, and clinical outcomes at three days, three months, and 12 months postoperatively.

CONCLUSION

CKH-UBO can achieve the same surgical outcomes as PPECF for the treatment of CSR. However, CKH-UBO saves more time but requires patients to undergo larger incisions.

The efficacy and safety of ultrasonic bone scalpel for removing retrovertebral osteophytes in anterior cervical discectomy and fusion: A retrospective study

In this study, we present a novel surgical method that utilizes the ultrasonic bone scalpel (UBS) for the removal of large retrovertebral osteophytes in anterior cervical discectomy and fusion (ACDF) and evaluate its safety and efficacy in comparison to the traditional approach of using high-speed drill (HSD). A total of 56 patients who underwent ACDF for retrovertebral osteophytes were selected. We recorded patients' baseline information, operation time, intraoperative blood loss, complications, JOA and VAS scores, and other relevant data. The mean operation time and the mean intraoperative blood loss in the UBS group were less than those in the HSD group (P < 0.05). Although both groups exhibited considerable improvements in JOA and VAS scores following surgery, there was no statistically significant difference between the two groups (P > 0.05). Additionally, no significant disparities were found in bone graft fusion between the two groups at 6- and 12-months postsurgery. Notably, neither group exhibited complications such as dura tear or spinal cord injury. Our study found that the use of UBS reduced operative time, minimized surgical bleeding, and led to clinical outcomes comparable to HSD in ACDF. This technique offers an effective and safe method of removing large retrovertebral osteophytes.

Using Piezosurgery in Anterior Cervical Discectomy and Fusion to Treat Complex Cervical Spondylotic Myelopathy Is Safe and Effective

Objective

To investigate the safety and efficacy of piezosurgery in anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM).

Methods

47 patients with complex CSM (cCSM) underwent ACDF surgery from 2014 to 2017. Among these patients, 26 underwent ACDF using piezosurgery (group A) and 21 underwent ACDF by using traditional tools such as high-speed air drill, bone curette, and Kerrison bone punch (group B). Average surgical time, intraoperative blood loss, surgical complications, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, and improvement rate were measured.

Results

Average surgical time and intraoperative blood loss were significantly lower in group A than those in group B (P < 0.01). The incidences of surgical complications were 3.8% and 23.8% in the A and B groups (P < 0.05), respectively. There were no significant differences in JOA scores and improvement rates between data collection periods at preoperative, 3-day postoperative, and 1-year postoperative follow-ups (P > 0.05).

Conclusion

For treating cCSM, both the piezosurgery and traditional tools led to significant neurological improvement. However, the piezosurgery was superior to the traditional tools in terms of surgical time, blood loss, and complication rate. Hence, piezosurgery was a safe and effective adjunct for ACDF treating cCSM.

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.

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.

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.

Angled Ultrasonic Bone Curette-Assisted Circumferential Decompression for Thoracic Myelopathy Caused by Severely Anterior Ossification

Objective

Thoracic myelopathy caused by severe anterior ossification is often progressive and fails to respond to conservative treatment. Removal of the compressing ossification is the most effective method but is hard to operate. In this study, we describe a novel one‐stage posterior circumferential decompressive procedure assisted by an angled ultrasonic bone curette (UBC) for thoracic myelopathy caused by severe anterior ossification and evaluate its safety and efficacy.

Methods

The current study enrolled 15 consecutive patients (five men and 10 women) with thoracic myelopathy caused by severely anterior ossification between January 2017 and December 2019. All patients underwent posterior circumferential decompression assisted by angled UBC and segmental instrumentation with interbody fusion. At the time of surgery, the average age was 58.6 ± 6.3 years (47–70 years). Before and after surgery, the patient data, clinical manifestation, operative levels, blood loss, operative time, perioperative complications, Japanese Orthopaedic Association (JOA) score were recorded and analyzed retrospectively.

Results

All patients had successful one‐stage posterior circumferential decompression to remove anterior ossifications directly. There were 12 cases of OPLL, two cases of a calcified giant herniated disc, and one case of osteophyte. The average operation time was 153.4 ± 53.4 min (77–242 min), with a mean blood loss of 463.5 ± 155.8 mL (240–780 mL). The average length of stay in the hospital was 14.3 ± 4.7 days (9–25 days) and the mean follow‐up duration was 20.8 ± 8.8 months (12–39 months). Almost all patients had subjective improvement in motor power and gait. The average preoperative JOA score was 4.5 ± 1.6, which improved to 9.0 ± 1.8 at the final follow‐up. Postoperative differences in the overall JOA scores showed significant improvement (F = 105.446, p < 0.01). The overall recovery rate at the final examination scored 70.9% ± 25.0%. According to Hirabayashi's classification, eight cases were rated as excellent, four as good, two as fair, and one as unchanged. No patient was graded as deteriorated. Two patients (13.3%) experienced intraoperative cerebrospinal fluid leakage, while two cases (13.3%) experienced unilateral intercostal neuralgia, and only one (6.7%) encountered acute neurological deterioration. All these patients were treated conservatively and their neurological function improved significantly. At the follow‐up, there was no evidence of neurological deterioration.

Conclusion

Circumferential decompression assisted by angled UBC can preserve more posterior elements of the involved levels, maintaining an intact pleura and reducing the operation time and blood loss for thoracic myelopathy caused by severe anterior ossification. It is a safe, effective, and technically feasible method to provide surgeons with a new option for thoracic spinal circumferential decompression.

Safety and Effectiveness of Modified Expansive Open-door Laminoplasty Using a Ultrasonic Bone Scalpel Compared With a High-speed Drill

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

Our study aimed to compare the effectiveness and safety of ultrasonic bone scalpel (UBS) and high-speed drill (HSD) in modified expansive open-door laminoplasty.

SUMMARY OF BACKGROUND DATA

The traditional methods of decompression mostly use HSD and laminectomy forceps to lift the lamina. As a new type of bone cutting instrument, UBS has the advantages of good tissue selectivity, bone cutting accuracy, good hemostasis, cold cutting, and easy operation, leading to its popular use in surgery.

MATERIALS AND METHODS

Forty-two patients who underwent modified expansive open-door laminoplasty for multilevel cervical spondylotic myelopathy were included in this study. They were divided into HSD and UBS groups (n=18 and 24, respectively). Data on demographics, operation duration, blood loss, postoperative drainage, extubation time, length of stay, cost of hospitalization, and complications were collected and compared. Modified Japanese Orthopedic Association score, visual analog scale, Neck Disability Index, and axial symptoms were also recorded and analyzed.

RESULTS

The blood loss in the UBS group was 255.4±217.5 mL, which was lower than that in the HSD group (490.6±389.4 mL, P=0.030). The cost of hospitalization was similar between the 2 groups. The operative time and postoperative drainage did not significantly differ (P>0.05). The modified Japanese Orthopedic Association score, visual analog scale score, and Neck Disability Index score after surgery were better than those before surgery (P<0.05), but no significant difference existed between the 2 groups in each period (P>0.05). No significant difference existed in the incidence of axial symptoms and other complications (P>0.05).

CONCLUSION

The application of the UBS to modified open-door laminoplasty resulted in a safe and effective decompression effect and reduced blood loss without increasing cost benefit.

Transpedicular bi-vertebrae wedge osteotomy in treatment of post-tubercular spinal deformity: a retrospective study

Background

In the late stage of spinal tuberculosis, the bony destruction and vertebral collapse often leads to significant kyphosis, presenting clinically as a painful gibbus deformity, with increased instability, vertebral body translations and increased risk of neurologic involvement. Spinal osteotomy is thought to be suitable for most patients with severe rigid kyphosis. The aim of this study was to evaluate the efficacy of transpedicular bi-vertebrae osteotomy technique in the patients with Pott’s kyphosis and other post-tubercular spinal deformity.

Methods

Between January 2012 and December 2015, 18 patients with post-tubercular spinal deformity underwent the transpedicular bi-vertebrae wedge osteotomy, with a minimum follow up of 27.0 months. Preoperative and postoperative kyphotic angle, sagittal plane parameters (TK for thoracic deformity, TLK for thoracolumbar and LL for lumbar deformity) and sagittal vertical axis (SVA) were measured. Oswestry Disability Index (ODI), Visual analog scale (VAS) and modified American Spinal Injury Association grading (ASIA) of preoperative and final follow-up were documented and compared.

Results

The average operation time was 305 minutes (range, 200–430 minutes) with a mean intraoperative blood loss of 425 mL (range, 200-700 mL). The kyphotic angles decreased from 80.3° (range, 28.5°-130.8°) preoperatively to 26.1° (range, 7.0°-63.3°) at the final follow-up (P<0.01). The mean VAS score was reduced from preoperative 5.2(range, 2-9) to 0.9(range, 0-2, P<0.01) and the ODI improved from 55.3% (range, 46%-76%) to 6.3% (range, 2%-18%, P<0.01). At final follow-up, there was radiographic evidence of solid fusion at the osteotomy site and fixed segments in all patients. Neurological function improved from ASIA scale D to E in 7 patients, C to D in 3 patients.

Conclusions

Our results suggest that transpedicular bi-vertebrae wedge osteotomy is a safe and effective treatment option for post-tubercular spinal deformity. This technique achieves satisfying correction and fusion rates with adequate decompression of neurological elements.

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.

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.

Ultrasonic bone scalpel for thoracic spinal decompression: case series and technical note

Background

Thoracic spinal stenosis (TSS) is a rare but intractable disease that fails to respond to conservative treatment. Thoracic spinal decompression, which is traditionally performed using high-speed drills and Kerrison rongeurs, is a time-consuming and technically challenging task. Unfavorable outcomes and high incidence of complications are the major concerns. The development and adaptation of ultrasonic bone scalpel (UBS) have promoted its application in various spinal operations, but its application and standard operating procedure in thoracic decompression have not been fully clarified. Therefore, the purpose of this study is to describe our experience and technique note of using UBS and come up with a standard surgical procedure for thoracic spinal decompression.

Methods

A consecutive of 28 patients with TSS who underwent posterior thoracic spinal decompression surgery with UBS between December 2014 and May 2015 was enrolled in this study. The demographic data, perioperative complications, operation time, estimated blood loss, and pre- and postoperative neurological statuses were recorded and analyzed. Neurological status was evaluated with a modified Japanese Orthopaedic Association (JOA) scale, and the neurological recovery rate was calculated using the Hirabayashi’s Method.

Results

Thoracic spinal decompression surgery was successfully carried out in all cases via a single posterior approach. The average age at surgery was 49.7 ± 8.5 years. The mean operative time of single-segment laminectomy was 3.0 ± 1.4 min, and the blood loss was 108.3 ± 47.3 ml. In circumferential decompression, the average blood loss was 513.8 ± 217.0 ml. Two cases of instrument-related nerve root injury occurred during operation and were cured by conservative treatment. Six patients experienced cerebrospinal fluid (CSF) leakage postoperatively, but no related complications were observed. The mean follow-up period was 39.7 ± 8.9 months, the average JOA score increased from 4.7 before surgery to 10.1 postoperatively, and the average recovery rate was 85.8%.

Conclusions

The UBS is an optimal instrument for thoracic spinal decompression, and its application enables surgeons to decompress the thoracic spinal cord safely and effectively. This standard operating procedure is expected to help achieve favorable outcomes and can be used to treat various pathologies leading to TSS.

Efficacy and Safety Analysis of Ultrasonic Bone Curette in the Treatment of Thoracic Spinal Stenosis

Objective

To investigate the efficacy and safety of ultrasonic bone curette in treating thoracic spinal stenosis.

Methods

A total of 30 patients of thoracic spinal stenosis who underwent posterior thoracic decompression in the hospital from December 2015 to 2017 were enrolled. Of these, 18 patients (group A) underwent posterior thoracic decompression using ultrasonic bone curette; and 12 patients underwent the treatment using a high‐speed drill (group B). The time of laminectomy, amount of intraoperative blood loss, presence or absence of cerebrospinal fluid leakage, and nerve root injury were recorded. All patients underwent X‐ray, computed tomography with three‐dimensional reconstruction, and magnetic resonance imaging before and after surgery. The Frankel classification and the Japanese Orthopaedic Association (JOA) scores were used to assess the neurological function and neurological recovery in patients. The measured data were statistically processed and analyzed using SPSS21.0 software, and the measurement data were expressed as mean ± SD.

Results

In groups A and B, the average time for single‐segment laminectomy was 3.3 ± 1.2 min and 6.0 ± 1.8 min and the mean bleeding volume was 105.5 ± 43.3 mL and 177.4 ± 54.7 mL, respectively, with a statistically significant difference between the groups. The difference in JOA scores before and after surgery in groups A and B was statistically significant. No significant difference was found between the groups, in group A, the improvement rate of nerve function at the last follow‐up was 71% and in group B, the improvement rate at the last follow‐up was 70%. In group A, at last follow‐up, two patients had Frankel grade B injury, one had grade C injury, seven had grade D injury, and eight had grade E injury. In group B, at last follow‐up, one patient had Frankel grade B injury, one had grade C injury, five had grade D injury, and five had grade E injury. The Frankel classification of both groups A and B significantly improved. Four patients experienced cerebrospinal fluid leakage in group A and five in group B, with no significant difference between the groups. There was no nerve root injury in both groups, and no complications, such as pulmonary infection and urinary tract infection, occurred after operation.

Conclusions

With the use of ultrasonic bone curette in posterior thoracic decompression, the decompression surgery could be completed relatively safely and quickly. It effectively reduced the amount of intraoperative blood loss.

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.

3D Real-Time Image-Guided Navigation Spine Corpectomy with Ultrasonic Bone Cutter: Technical Note

BACKGROUND

Surgical interventions for congenital scoliosis are challenging for spine surgeons. The coordination of 3-dimensional (3D), real-time, image-guided navigation with an ultrasonic bone cutter allows surgeons to localize the affected area of the spine accurately and remove the lesion without damaging soft tissue structures. The goal of this technical paper is to report a previously undescribed method of hemivertebrectomy that combines 3D, real-time, image-guided navigation and an ultrasonic bone cutter. We highlight the feasibility and safety of this method in spinal surgery.

METHODS

Three patients with congenital scoliosis were treated with this technique. We present three illustrative cases comprising hemivertebrectomies for congenital scoliosis. Intraoperative photos demonstrating the technique are also provided.

RESULTS

All surgeries were completed without complications. The hemivertebrae were completely removed, and marked correction of congenital scoliosis was noted.

CONCLUSIONS

We believe that the combination of 3D, real-time image navigation and an ultrasonic bone cutter improves hemivertebrectomy by increasing accuracy and avoiding dura laceration, major organ damage, or potential vessel damage.

The Efficacy of Ultrasonic Bone Scalpel for Unilateral Cervical Open-Door Laminoplasty: A Randomized Controlled Trial

BACKGROUND

In cervical open-door laminoplasty for cervical myelopathy, a high-speed rotatory drill and rongeurs are used to make unicortical troughs and bicortical openings in the laminae. The lamina is reflected at the trough to enlarge the spinal canal, followed by bone healing on the hinge side to stabilize laminoplasty. The ultrasonic bone scalpel (UBS) has been used due to theoretical advantages including a better hinge union rate, less soft tissue trauma, less neurological injury, and shorter operative time.

OBJECTIVE

To assess the superiority of UBS for hinge union compared to the drill through randomized controlled trial.

METHODS

In 190 randomly allocated cervical myelopathy patients, the trough and opening at the lamina were made using either the drill (n = 95) or UBS (n = 95) during 2015 to 2018. The primary outcome was the hinge union rate on 6-mo postoperative computed tomography. Secondary outcomes included the hinge union rate at 12 mo, the operative time, intraoperative/postoperative bleeding, neurological injury, complications, and clinical outcomes over a 24-mo follow-up.

RESULTS

Hinge union in all laminae was achieved in 60.0% (drill) and 43.9% (UBS) of patients at 6 mo (intention-to-treat analysis; P = .02; odds ratio, 2.1) and in 91.9% (drill) and 86.5% (UBS) at 12 mo. Dural injury only occurred in the drill group (2.1%), and the UBS group showed significantly less intraoperative bleeding (P < .01). The other secondary outcomes did not differ between groups.

CONCLUSION

The hinge union rate was inferior in the UBS group at 6 mo postoperatively, but UBS was efficacious in reducing dural injuries and bleeding.

Characteristics of ultrasound device: a new technology for bone curettage and excavation

Background

Ultrasonic (US) devices are used in laparoscopic, dental, and spinal surgeries, while it is difficult to use for the joint under irrigation and perfusion solutions due to lack of power. A new US device is developed with greater voltage improvement and has been implemented in the arthroscopic field. The aim is to compare the characteristics of the US devices with the conventional ones in water.

Methods

Twenty bone blocks from the porcine femur were settled in a holder in water. A 4.0 mm diameter abrader burr moved 15 mm along the long axis of the bone block in ten blocks for three times. A 4.3 mm wide curette blade powered by ultrasonic vibration was moved in the same manner in the other ten blocks. The gutter shape, including the gutter depth and the bottom angle of the gutter, and the curetted area ratio of the gutter were assessed.

Forty bones blocks from the porcine femurs were clamped with a holder in water, while the cortical bone surface must be located on the side. A 5 mm diameter drill excavated the bone along the previously-inserted guide wire to the 15 mm depth for twenty blocks. Next, the US excavation probe of 5x4mm rectangular shape was moved to the same depth in the other twenty blocks. Each ten block was cut in half along the bone tunnel and was assessed the surface roughness at three area, while the cross-sectional area (CSA) of the tunnel were measured and the ratio of the measured CSA was calculated based on an expected CSA in the remaining ten blocks for each device.

Results

The depth of curettage and bottom angle were significantly smaller with the US device than with the abrader burr at all planes, while the curetted area ratio created by each device was mostly equal to the other. Surface roughness was similar in two evacuating devices except one area. CSA ratio with the US excavation device was significantly smaller than that with the drill.

Conclusion

US curettage has an advantage to flatly curette bone surfaces, while a bone tunnel can be accurately created with the US device.

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.

Novel approach using ultrasonic bone curettage and transoral robotic surgery for en bloc resection of cervical spine chordoma: case report

Chordomas are rare, locally aggressive neoplasms that develop from remnants of the notochord. The typical approach to chordomas of the clivus and axial cervical spine often limits successful en bloc resection. In this case report, authors describe the first-documented transoral approach using both transoral robotic surgery (TORS) for exposure and the Sonopet bone scalpel under navigational guidance to achieve en bloc resection of a cervical chordoma. This 27-year-old man had no significant past medical history (Charlson Comorbidity Index 0). During a trauma workup following a motor vehicle collision, a CT of the patient's cervical spine demonstrated an incidental 2.2-cm lesion situated along the posterior aspect of the C2 vertebral body. Postoperative imaging showed successful en bloc resection with adequate placement of hardware, and the pathology report demonstrated negative resection margins. The patient tolerated the procedure well, and because of the successful en bloc resection, radiation has been deferred. At 7 months postoperatively, the patient returned to work in New York City. Contrasted MRI at 15 months postoperatively showed the patient to be disease free. This approach offers a promising way forward in the treatment of these complex tumors.

The Role of Powered Surgical Instruments in Ear Surgery: An Acoustical Blessing or a Curse?

Ear surgery in many ways lagged behind other surgical fields because of the delicate anatomical structures within the ear which leave surgeons with little room for error. Thus, while surgical instruments have long been available, their use in the ear would most often do more damage than good. This state of affairs remained the status quo well into the first half of the 20th century. However, the introduction of powered surgical instruments, specifically the electric drill used in conventional microscopic ear surgery (MES) and the ultrasonic aspirator, the Sonopet® Omni, in transcanal endoscopic ear surgery (TEES) marked major turning points. Yet, these breakthroughs have also raised concerns about whether the use of these powered surgical instruments within the confines of the ear generated so much noise and vibrations that patients could suffer sensorineural hearing loss as a result of the surgery itself. This paper reviews the intersection between the noise and vibrations generated during surgery; the history of surgical instruments, particularly powered surgical instruments, used in ear surgeries and the two main types of surgical procedures to determine whether these powered surgical instruments may pose a threat to postoperative hearing.

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.

[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.

Heat generation by ultrasonic bone curette comparing with high-speed drill

BACKGROUND

Ultrasonic bone curettes have been used as with high-speed drills. However, the amount of heat generated by the ultrasonic bone curette is not well known. This study quantitatively assessed the heat generated by an ultrasonic bone curette and compared it to that by a high-speed drill.

METHODS

The thermal change in a swine skull during bone curetting using an ultrasonic device and a high-speed drill were assessed. The investigation focused on the type of surgical manipulation (brush-like strokes vs. pushing motion) and irrigation (room temperature vs. cold water; low-volume irrigation vs. high-volume irrigation).

RESULTS

The thermal elevation during drill use was suppressed when using brush-like strokes compared to pushing motion (brush-like strokes, 44.7 °C; pushing motion, 69.2 °C; p < 0.01). Cold-water irrigation while drilling had a small effect compared to room temperature (RT) water (RT, 44.7 °C; cold, 35.2 °C; p = 0.12). The temperature generated by the curette was higher than that generated by the drill (curette, 72.5 °C; drill, 44.7 °C; p < 0.01). High-volume irrigation was required to reduce the heat generated by the curette (no irrigation, 88.6 °C; low-volume, 72.5 °C; high-volume, 60.5 °C; p < 0.01).

CONCLUSIONS

The ultrasonic bone curate generated more heat than the high-speed drill. During surgical manipulation, the use of brush-like strokes by both the high-speed drill and the ultrasonic bone curette is necessary to avoid excess thermal elevation. Irrigation with RT water is sufficient to avoid heat generation. High-volume irrigation is required to reduce the heat generated by the curette.

Use of Ultrasonic Device in Cervical and Thoracic Laminectomy: a Retrospective Comparative Study and Technical Note

Multilevel severe compressive myelopathy is a challenging disorder for the surgeons, the aim of this study is to assess the efficacy and safety of a newly designed ultrasonic burr as an assistant tool to the ultrasonic scalpel in laminectomy for this disease. This is a retrospective comparative study, the included subjects were patients who received cervical and thoracic laminectomy using ultrasonic device (LUD, n = 9, 10 surgeries) and controls with the high-speed burr (LHB, n = 16). Fifteen patients (60.0%) showed severe cord occupancy and the average number of laminae operated was 3.5. Ultrasonic devices caused less blood loss (P = 0.02) and quicker operative time per level (P < 0.001) than LHB, and was associated with more operated laminae (P = 0.04). Preoperative JOA scores (P = 0.51), improvement rate (P = 0.47), and dural injury (P = 0.51) were not related to LUD. Our experience indicates ultrasonic devices are safe and effective for laminectomy treating multilevel and severe compressive myelopathy, the instrument could be used with ease especially for cases with ossified posterior longitudinal ligament and ossification of the ligamentum flavum, proper utility of the instrument is crucial to prevent complications.

Use of an Ultrasonic Bone Curet for the Extraction of a Cervical Artificial Disc: A Novel Application: A Case Report

CASE

Eighteen months after implantation of a C6-C7 cervical artificial disc (ProDisc-C; DePuy Synthes), a 44-year-old woman presented with right-sided C7 radiculopathy. Imaging revealed posterior subsidence of the prosthesis, with C7 foraminal stenosis. An ultrasonic curet was used to safely and effectively extract the prosthesis without neurologic complication; safe access for the insertion of an intervertebral cage was facilitated.

CONCLUSION

The ultrasonic curet was a safe and effective adjunct for revision artificial cervical disc replacement surgery; this technique may help to reduce potential injury to neural structures in a procedure with a traditionally high complication rate.

Ultrasonic bone aspirator use in endoscopic ear surgery: feasibility and safety assessed using cadaveric temporal bones

Objectives:

To describe the feasibility and assess the safety of using an ultrasonic bone aspirator in endoscopic ear surgery.

Methods:

Five temporal bones were dissected via endoscopic ear surgery using a Sonopet ultrasonic bone aspirator. Atticoantrostomy was undertaken. Another four bones were dissected using routine endoscopic equipment and standard bone curettes in a similar manner. Feasibility and safety were assessed in terms of: dissection time, atticoantrostomy adequacy, tympanomeatal flap damage, chorda tympani nerve injury, ossicular injury, ossicular chain disruption, facial nerve exposure and dural injury.

Results:

The time taken to perform atticoantrostomy was significantly less with the use of the ultrasonic bone aspirator as compared to conventional bone curettes.

Conclusion:

The ultrasonic bone aspirator is a feasible option in endoscopic ear surgery. It enables easy bone removal, with no additional complications and greater efficacy than traditional bone curettes. It should be a part of the armamentarium for transcanal endoscopic ear surgery.

Safety and efficacy of cervical laminoplasty using a piezosurgery device compared with a high-speed drill

BACKGROUND

Piezosurgery is a relatively new osteotomy technique using microvibrations of scalpels at ultrasonic frequencies to perform safe and effective osteotomies without damage to adjacent soft tissue, which is widely used in spinal, oral, and maxillofacial surgery. We hypothesized that such a device could also be useful in cervical laminoplasty. The purpose of this study was to compare the safety and efficacy of a piezosurgery device with those of a highspeed drill in cervical laminoplasty.

METHODS

A prospectively randomized clinical study was designed. Forty-two consecutive patients were enrolled in the study. All patients underwent modified expansive open-door laminoplasty and were randomly divided into 2 groups according to the instrument for transection of the lamina, using high-speed drill (drill group) or piezosurgery device (piezosurgery group). The operation time, intraoperative blood loss, and postoperative drainage were recorded. Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) as clinical assessments were quantified.

RESULTS

No significant difference was observed in the operation time between the 2 groups. In the piezosurgery group, there were less loss of the intraoperative blood and postoperative drainage compared with the drill group. However, clinical results (VAS and JOA scores) showed no significant difference between both groups during the all follow-up periods.

CONCLUSION

The piezosurgery is a useful instrument and at least as safe and efficacious as the conventional high-speed drill in cervical laminoplasty.

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.

The Reliability of the Ultrasonic Bone Scalpel in Cervical Spondylotic Myelopathy: A Comparative Study of 46 Patients

BACKGROUND

In patients with cervical spondylotic myelopathy (CSM), laminectomy is usually performed with a Kerrison rongeur or a high speed drill (HSD).The HSD, which is most often selected for laminectomy, may cause complications such as duratomy, thermal and mechanical neural injuries. With an ultrasonic bone scalpel (UBS), a less traumatic laminectomy can be performed in a shorter time. The aim of this study was to compare the results of laminectomies using HSD and UBS.

METHODS

Evaluation was made in 46 patients who were operated on for CSM. Cervical laminectomy was performed on 23 patients using the UBS (group I) and to 23 using the HSD (group II). A comparison was made of the 2 groups in respect of demographic characteristics, laminectomy levels, mean laminectomy duration, bleeding rates, and surgical complications.

RESULTS

In group I, the mean laminectomy time was 2.2 ± 0.4 min/level, mean blood loss was 180 mL, hospitalization was 3.0 ± 0.0 days, and C5 radiculopathy was seen in 1 patient. In group II, the mean laminectomy time was 7.4 ± 2.6 min/level, mean blood loss was 380 mL, hospitalization was 3.7 ± 1.3 days, C5 radiculopathy was seen in 1 patient and dura injuries in 3 patients. The recovery rate was determined as 47.6% in group I and 48.8% in group II.

CONCLUSIONS

For patients with CSM, laminectomy using the UBS provides a safe, rapid, and effective decompression with a lesser blood loss. The low rate of complications lessens the postoperative morbidity rates and shortens hospital stay.

Biofouling of surgical power tools during routine use

Surgical power tools (SPTs) are frequently used in many surgical specialties such as dentistry, orthopaedics, ophthalmology, neurology, and podiatry. They have complex designs that may restrict access to cleaning and sterilization agents and frequently become contaminated with microbial and tissue residues following use. Due to these challenges, surgical power tools can be considered the weak link in the decontamination cycle and present a potential for iatrogenic transmission of infection. We aimed to review the existing literature on the decontamination of surgical power tools and associated iatrogenic transmission of infection. A search of the medical literature was performed using Ovid online using the following databases: Ovid Medline 1950-2014, Embase 1980-2014, and EBM Reviews Full Text--Cochrane DSR, ACP Journal Club, and Dare. Despite challenges to decontamination processes, reported episodes of iatrogenic infection directly linked to SPTs appear rare. This may reflect a true picture but more likely represents incomplete reporting, failure to investigate power tools, or lack of surveillance linking surgical site infections (SSIs) to power tools. Healthcare professionals should be aware of the complexities associated with the decontamination of different SPTs, and should review manufacturers' reprocessing instructions prior to purchase. More clarity is required in the manufacturers' validation of these reprocessing instructions. This particularly applies to the emerging surgical robot systems that present extreme challenges to decontamination between uses. Investigation of cross-infection incidents or SSI surveillance should include an element of assessment of SPT decontamination to further elucidate the contribution of SPTs to skin and soft tissue infections.

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.

Use of Piezosurgery for removal of retrovertebral body osteophytes in anterior cervical discectomy

BACKGROUND CONTEXT

The relatively new technique of Piezosurgery is based on microvibrations, generated by the piezoelectrical effect, which results in selective bone cutting with preservation of adjacent soft tissue.

PURPOSE

To study the applicability of Piezosurgery in anterior cervical discectomy with fusion (ACDF) surgery.

STUDY DESIGN/SETTING

Prospective clinical study at the neurosurgical department of the University of Freiburg, Germany.

PATIENT SAMPLE

Nine patients with cervical disc herniation and retrovertebral osteophytes who underwent ACDF surgery.

OUTCOME MEASURES

Piezosurgery was evaluated with respect to practicability, safety, preciseness of bone cutting, and preservation of adjacent neurovascular tissue. Pre- and postoperative clinical and radiological data were assessed.

METHODS

Piezosurgery was supportively used in ACDF in nine patients with either radiculopathy or myelopathy from disc herniation or ventral osteophytes. After discectomy, osteophytes were removed with Piezosurgery to decompress the spinal canal and the foramina. Angled inserts were used, allowing for cutting even retrovertebral osteophytes.

RESULTS

In all nine cases, Piezosurgery cut bone selectively with no damage to nerve roots, dura, or posterior longitudinal ligament. None of the patients experienced any new neurological deficit after the operation. The handling of the instrument was safe and the cut precise. Osteophytic spurs, even retrovertebral ones that generally only can be approached via corpectomies, could be safely removed because of the angled inserts through the disc space. Currently, a slightly prolonged operation time was observed for Piezosurgery. Furthermore, the design of the handpiece could be further improved to facilitate the intraoperative handling in ACDF.

CONCLUSIONS

Piezosurgery proved to be a useful and safe technique for selective bone cutting and removal of osteophytes with preservation of neuronal and soft tissue in ACDF. In particular, the angled inserts were effective in cutting bone spurs behind the adjacent vertebra which cannot be reached with conventional rotating burs.

Application of ultrasonic bone curette in endoscopic endonasal skull base surgery: technical note

Background Endoscopic endonasal surgery (EES) of the skull base often requires extensive bone work in proximity to critical neurovascular structures. Objective To demonstrate the application of an ultrasonic bone curette during EES. Methods Ten patients with skull base lesions underwent EES from September 2011 to April 2012 at the University of Pittsburgh Medical Center. Most of the bone work was done with high-speed drill and rongeurs. The ultrasonic curette was used to remove specific structures. Results All the patients were submitted to fully endoscopic endonasal procedures and had critical bony structures removed with the ultrasonic bone curette. Two patients with degenerative spine diseases underwent odontoid process removal. Five patients with clival and petroclival tumors underwent posterior clinoid removal. Two patients with anterior fossa tumors underwent crista galli removal. One patient underwent unilateral optic nerve decompression. No mechanical or heat injury resulted from the ultrasonic curette. The surrounding neurovascular structures and soft tissue were preserved in all cases. Conclusion In selected EES, the ultrasonic bone curette was successfully used to remove loose pieces of bone in narrow corridors, adjacent to neurovascular structures, and it has advantages to high-speed drills in these specific situations.

Microsurgical medial fenestration with an ultrasonic bone curette for lumbar foraminal stenosis

BACKGROUND

Misdiagnosis and inadequate treatment of lumbar foraminal stenosis (LFS) are the most common causes of failed back surgery. Although several surgical procedures have been reported, the optimal surgical treatment remains controversial.

AIM

We describe our method of microsurgical medial fenestration using an ultrasonic bone curette (Sonopet, Stryker Corp., Kalamazoo, MI, USA) to treat patients with LFS and report our early results.

PATIENTS AND METHODS

We followed up 26 patients who had undergone microsurgical medial fenestration at least 1 year earlier. The patients were 15 men and 11 women with a mean age at surgery of 59.5 years; the mean follow-up period was 30.6 months. The affected nerve root was at L4 in 1 patient and at L5 in 25. Evaluation of our clinical results was based on the Japanese Orthopedic Association score.

RESULTS

There were no intraoperative surgery-related complications. After surgery, 1 patient had recurrence of L5 radiculopathy associated with iatrogenic spondylolysis. He was successfully treated with resection of the inferior articular process without fusion surgery; there was loss of disc height without obvious instability at the corresponding level. The Japanese Orthopedic Association scores showed significant improvement at 1 month after surgery and at final follow-up (p<0.001). No patient had spinal instability or malalignment postoperatively.

CONCLUSIONS

Microsurgical medial fenestration using Sonopet, a less-invasive surgical technique that does not result in spinal instability or malalignment, yielded excellent clinical outcomes.

Cervical anterior fusion with the Williams-Isu method: clinical review

Anterior decompression and fusion of the cervical spine is a widely accepted treatment for cervical canal disease. The Williams-Isu method involves cervical anterior fusion with autologous bone grafts from cervical vertebral bodies. Its advantages are a wide operative field, excellent graft fusion, the absence of problems related to the iliac donor site, and direct visualization of the nerve root. For detailed decompression of the cervical root, an ultrasonic bone curette (SONOPET, Stryker Japan K.K., Tokyo) may be useful. To prevent graft extrusion, bioabsorbable screws featuring a head are placed in 4 corners of the bone graft and are fixed with a tap on a part of the graft. The screws are visualized on postoperative X-ray, computed tomography, and magnetic resonance imaging studies. In 69 patients reported elsewhere there were no complications attributable to screw insertion, screw or graft extrusion, or surgery-related infections. When adequate bone cannot be harvested, a piece of ceramic hydroxyapatite is placed between the bone grafts. This sandwich method reinforces the graft, and radiological evidence suggests that it yields better results with respect to the angle and height of the fused segment. For the surgical treatment of cervical ossification of the posterior longitudinal ligament, a large vertebral bone window and a large bone graft are needed; this may result in postoperative radiological worsening. Radiological studies have shown that cervical ossification of the posterior longitudinal ligament can, as can cervical spondylosis, be addressed with the Williams-Isu method. Detailed radiological studies in patients treated with the Williams-Isu method have demonstrated that the range of motion and the disc height of the fused segment must be considered to prevent worsening in that segment after anterior fusion. The Williams-Isu method cannot completely correct cervical alignment, and great caution must be exercised in patients with preoperative malalignment. To reduce the levels to be fused in patients with multilevel lesions due to cervical disease, the Williams-Isu method can be combined with the transvertebral approach. The transvertebral approach facilitated by the wide Williams-Isu window allows the root bifurcation area to be confirmed during the early stage of surgery and possible decompression along the root. Radiological examination has shown that the combination of the Williams-Isu method and transvertebral approach does not affect the fusion level compared with the Williams-Isu method alone and produces better results than does the transvertebral approach alone.

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

Object

Unintended durotomies are a common complication of spine surgery and are often correlated with increased postoperative morbidity. Recently, ultrasonic bone curettes have been introduced in spine surgery as a possible alternative to the conventional high-speed drill, offering the potential for greater bone-cutting precision and less damage to surrounding soft tissues. To date, however, few studies have investigated the safety and efficacy of the ultrasonic bone curette in reducing the rates of incidental durotomy compared with the high-speed drill.

Methods

The authors retrospectively reviewed the records of 337 consecutive patients who underwent posterior cervical or thoracic decompression at a single institution between January 2009 and September 2011. Preoperative pathologies, the location and extent of spinal decompression, and the use of an ultrasonic bone curette versus the high-speed drill were noted. The rates of incidental durotomy, as well as hospital length of stay (LOS) and perioperative outcomes, were compared between patients who were treated using the ultrasonic bone curette and those treated using a high-speed drill.

Results

Among 88 patients who were treated using an ultrasonic bone curette and 249 who were treated using a high-speed drill, 5 (5.7%) and 9 (3.6%) patients had an unintentional durotomy, respectively. This finding was not statistically significant (p = 0.40). No patients in either cohort experienced statistically higher rates of perioperative complications, although patients treated using an ultrasonic bone curette tended to have a longer hospital LOS. This difference may be attributed to the fact that this series contained a statistically higher number of metastatic tumor cases (p < 0.0001) in the ultrasonic bone curette cohort, likely increasing the LOS for that patient population. In 13 patients, the dural defect was repaired intraoperatively. No patients who experienced an incidental durotomy had new-onset or permanent neurological deficits postoperatively.

Conclusions

The safety and efficacy of ultrasonic bone curettes in spine surgery has not been well established. This study shows that the ultrasonic bone curette has a similar safety profile compared with the high-speed drill, although both are capable of causing iatrogenic dural tears during spine surgery.