A light-powered self-rotating liquid crystal elastomer drill

Self-oscillating systems can directly convert ambient energy to mechanical work, and new type self-oscillating systems are worth designing for applications in energy harvesters, engines, and actuators. Taking inspiration from the hand drill, we have developed a novel self-rotating drill system, which is consist of a turnplate and a liquid crystal elastomer (LCE) fiber under steady illumination. To investigate the self-rotating behaviors of the LCE drill, we have proposed a nonlinear theoretical model of the LCE drill under steady illumination based on the well-established dynamic LCE model. Numerical calculation reveals that the LCE drill can undergo a supercritical Hopf bifurcation between the static regime and the self-rotation regime. The self-rotation of drill originates from the contraction of winding portion of LCE fiber in illumination at winding state, and its continuous periodic motion is sustained by the interrelation between light energy and damping dissipation. The Hopf bifurcation conditions are also investigated in detail, as well as the vital system parameters affecting its frequency and amplitude. In contrast to the abundant existing self-oscillating systems, this self-rotating drill stands out due to its simple and lightweight structure, customizable dimensions, and high speed, and thus facilitates the design of compact and integrated systems, enhancing their applicability in microdevices and systems. This bears great significance in fields like micro-robotics, micro-sensors, and medical instruments, enabling the realization of smaller and higher-performance devices.

Evaluation of inner ear damage by mastoid drilling with measurement of serum prestin (SLC26A5) levels

OBJECTIVE

The objective of this study is to demonstrate any inner ear injury caused by drilling in mastoid surgery with prestin, outer hair cell motor protein specific to the cochlea.

METHODS

The patients with chronic otitis media requiring mastoidectomy (n = 21) and myringoplasty (n = 21) were included. Serum prestin level obtained from blood samples was measured before surgery and on postoperative days 0, 3, and 7 using Human Prestin (SLC26A5) ELISA Kit. All patients underwent the Pure Tone Audiometry (PTA) test before surgery and on the postoperative 7th day. The drilling time was also recorded for all patients who underwent mastoidectomy.

RESULTS

In both mastoidectomy and myringoplasty groups, the postoperative serum prestin levels increased on days 0 and 7 (pday-0 = 0.002, pday-7 = 0.001 and pday-0 = 0.005, pday-7 = 0.001, respectively). There was no significant difference in the serum prestin levels between the two groups, postoperatively. The PTA thresholds at day 7 did not change in either group. A significant decline at 2000 Hz of bone conduction hearing threshold in both groups and a decline at 4000 Hz in the myringoplasty group were found. There was no correlation between the drilling time and the increase of prestin levels in the postoperative day 0, 3, and 7.

CONCLUSION

Our results showed that mastoid drilling is not related to a significant inner ear injury. Although the myringoplasty group was not exposed to drill trauma, there was a similar increase in serum prestin levels as the mastoidectomy group. Also, a significant decline at 2000 Hz of bone conduction hearing threshold in both groups and a decline at 4000 Hz in the myringoplasty group were found. These findings suggest that suction and ossicular manipulation trauma can lead to an increase in serum prestin levels and postoperative temporary or permanent SNHL at 2000 and 4000 Hz.

LEVEL OF EVIDENCE

Level-4.

Temperature change during orthopedic drilling procedures: An experimental surgical internal fixation simulation study

Background

The purpose of this experimental surgical internal fixation simulation study was to analyze four drilling parameters as a whole, use a thermal camera to observe the temperature, and then determine how these parameters were related to temperature.

Methods

Four separate experimental models were examined in terms of the impacts of four drilling parameters, defined as the drill, drill bit diameter, drill bit design, and the material drilled during drilling procedures, on temperature.

Results

The temperature was observed to be affected by the drill used, a change in the drill bit diameter, drill bit design, and the characteristics of the material drilled (p < 0.041, p < 0.001, p < 0.001, and p < 0.001, respectively). The speeds of the four drills used were measured as 558 rpm, 1385 rpm, 930 rpm, and 1490 rpm.

Conclusion

The findings of the present research demonstrated that the four parameters investigated were related to the temperature formed during drilling. Of the parameters examined, the parameter which increased the temperature the most was a change in the drill bit diameter.

Roxborough Park Community Wildfire Evacuation Drill: Data Collection and Model Benchmarking

Wildfires are increasing in scale, frequency and longevity, and are affecting new locations as environmental conditions change. This paper presents a dataset collected during a community evacuation drill performed in Roxborough Park, Colorado (USA) in 2019. This is a wildland-urban interface community including approximately 900 homes. Data concerning several aspects of community response were collected through observations and surveys: initial population location, pre-evacuation times, route use, and arrival times at the evacuation assembly point. Data were used as inputs to benchmark two evacuation models that adopt different modelling approaches. The WUI-NITY platform and the Evacuation Management System model were applied across a range of scenarios where assumptions regarding pre-evacuation delays and the routes used were varied according to original data collection methods (and interpretation of the data generated). Results are mostly driven by the assumptions adopted for pre-evacuation time inputs. This is expected in communities with a low number of vehicles present on the road and relatively limited traffic congestion. The analysis enabled the sensitivity of the modelling approaches to different datasets to be explored, given the different modelling approaches adopted. The performance of the models were sensitive to the data employed (derived from either observations or self-reporting) and the evacuation phases addressed in them. This indicates the importance of monitoring the impact of including data in a model rather than simply on the data itself, as data affects models in different ways given the modelling methods employed. The dataset is released in open access and is deemed to be useful for future wildfire evacuation modelling calibration and validation efforts.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10694-023-01371-1.

Limited evidence of adjuvant biologics with bone marrow stimulation for the treatment of osteochondral lesion of the talus: a systematic review

PURPOSE

To evaluate the complication rates, continuous functional outcome scores, and return to play data following bone marrow stimulation (BMS) versus biologics ± BMS for the treatment of osteochondral lesion of the talus (OLT).

METHODS

A systematic review was performed. The PubMed and Embase databases were searched using specific search terms and eligibility criteria according to the PRISMA guidelines. The level of evidence was assessed using published criteria by The Journal of Bone & Joint Surgery, and the quality of evidence using the Modified Coleman Methodology Score. Continuous variables were presented as mean ± standard deviation and categorical variables as frequencies (percentages).

RESULTS

BMS versus BMS + hyaluronic acid (HA): no complications in either treatment arm were reported. The mean American Orthopaedic Foot and Ankle Society score was 43.5 to 67.3 points and 44.0 to 72.4 points, respectively. The mean 10 mm Visual Analogue Scale pain score was 7.7 to 3.8 points and 7.5 to 2.5 points, respectively. BMS versus BMS + concentrated bone marrow aspirate (CBMA): the pooled overall complication rate was 17/64 (26.6%) versus 11/71 (15.5%), respectively (non-significant). The pool revision rate was 15/64 (23.4%) versus 6/71 (8.5%), respectively (p = 0.016). There has been a notable poor reporting of complication rates for the use of ADSC and PRP as adjuvant biological therapies to BMS for the treatment of OLT.

CONCLUSION

There was an overall limited comparative clinical evidence of adjuvant biologics with BMS versus BMS alone for the treatment of OLT. BMS + HA and BMS + CBMA can provide superior outcomes, albeit the currently limited evidence. Further studies are warranted to establish the true clinical superiority of the various biologics ± BMS versus BMS alone. These studies must also compare the various biologics against one another to determine, if any, the optimal biologic for OLT. Clinicians should counsel patients accordingly on these findings as required.

LEVEL OF EVIDENCE

Level III.

Power versus manual pedicle tract preparation: a multi-center study of early adopters

STUDY DESIGN

Retrospective cohort, multicenter. A single surgeon study demonstrated that pedicle tract preparation with power tools was associated with lower fluoroscopy times and revision rates compared to manual tools, while maintaining patient safety.

OBJECTIVE

Our purpose was to determine the safety of power-assisted pedicle tract preparation by early adopters of this technology.

METHODS

Retrospective review comparing patients that underwent posterior spinal fusion by seven pediatric spine surgeons at six institutions between January 1, 2008 and August 31, 2019. The manual pedicle tract preparation used a pedicle awl. Power tract preparation used a flexible 2.0-2.4 mm drill bit, followed by a larger drill bit or a reamer. All screws were inserted with power technique.

RESULTS

In the manual tract preparation group, 9424 screws were placed in 585 cases. In the power tract preparation group, 22,209 screws were placed in 1367 cases. Seven patients (7/1952; 0.36%; 95% CI: 0.14-0.74%) had 11 mal-positioned screws (11/31,633; 0.03%; 95% CI: 0.017-0.062%). Seven screws (7/9424; 0.07%; 95% CI: 0.030-0.15%) were in the manual cohort and four (4/22,209; 0.02%; 95% CI: 0.0049-0.046%) were in the power cohort. There were significantly more revisions per screw in the manual cohort (p = 0.02). However, there were not significantly more revisions per patient in the manual cohort (manual: 0.5%, 3/585 vs. power: 0.3%, 4/1,367; p = 0.43). Of these seven, three patients (3/585; 0.5%; 95% CI: 0.1-1.5%) experienced neurologic injury or neuro-monitoring changes requiring screw removal in the manual cohort, and 1 patient (1/1,367, 0.07%; 95% CI: 0.002-0.4%) in the power cohort (p = 0.08). Three additional patients underwent revision in the power cohort: 1 for an asymptomatic lateral breech, 1 for a spinal headache/medial breech that developed after an MVA, and 1 for an iliac vein injury during pedicle tract preparation.

CONCLUSION

This is the first multi-center study examining power pedicle preparation. Overall, 99.9% of pedicle screws placed with power pedicle preparation did not have complications or revision. Equivalent patient safety was demonstrated compared to manual technique.

LEVEL OF EVIDENCE

III.

Aerosol and droplet generation from orbital repair: Surgical risk in the pandemic era

INTRODUCTION

The highly contagious COVID-19 has resulted in millions of deaths worldwide. Physicians performing orbital procedures may be at increased risk of occupational exposure to the virus due to exposure to secretions. The goal of this study is to measure the droplet and aerosol production during repair of the inferior orbital rim and trial a smoke-evacuating electrocautery handpiece as a mitigation device.

MATERIAL AND METHODS

The inferior rim of 6 cadaveric orbits was approached transconjunctivally using either standard or smoke-evacuator electrocautery and plated using a high-speed drill. Following fluorescein inoculation, droplet generation was measured by counting under ultraviolet-A (UV-A) light against a blue background. Aerosol generation from 0.300-10.000 μm was measured using an optical particle sizer. Droplet and aerosol generation was compared against retraction of the orbital soft tissue as a negative control.

RESULTS

No droplets were observed following the orbital approach using electrocautery. Visible droplets were observed after plating with a high-speed drill for 3 of 6 orbits. Total aerosol generation was significantly higher than negative control following the use of standard electrocautery. Use of smoke-evacuator electrocautery was associated with significantly lower aerosol generation in 2 of 3 size groups and in total. There was no significant increase in total aerosols associated with high-speed drilling.

DISCUSSION AND CONCLUSIONS

Droplet generation for orbital repair was present only following plating with high-speed drill. Aerosol generation during standard electrocautery was significantly reduced using a smoke-evacuating electrocautery handpiece. Aerosols were not significantly increased by high-speed drilling.

An affordable and miniature ice coring drill for rapid acquisition of small iceberg samples

Icebergs account for approximately half of the freshwater flux from the Greenland Ice Sheet and they can impact marine ecosystems by releasing nutrients and sediments into the ocean as they drift and melt. Parameterizing iceberg fluxes of nutrients and sediments to fjord and ocean waters remains a difficult task due to the complexity of ice-ocean interactions and is complicated by a lack of observations. Acquiring iceberg samples can be difficult and dangerous, as icebergs can break apart and roll without warning. Here we present open source design files for a small, lightweight ice coring drill that can be reproduced using modern computer numerical control (CNC) machining and 3D printing technology. This ice core drill can rapidly acquire small ice samples from icebergs and bergy bits using a standard commercial, off-the-shelf battery-operated hand drill. Design files and a recent field expedition to Northwest Greenland are described. Ice core collection required only 30 s, thereby minimizing risks to scientists.

CT-guided percutaneous biopsy of sclerotic bone lesions: diagnostic outcomes

OBJECTIVE

To determine the diagnostic yield of CT-guided percutaneous biopsy of densely sclerotic bone lesions.

MATERIALS AND METHODS

We retrospectively analyzed CT-guided percutaneous bone biopsies performed at our institution from September 2008 through August 2011 (329 cases) and from September 2012 through August 2015 (324 cases) after adoption of a battery-powered drill system (OnControl). Bone lesions were included in the analysis if they were >70% sclerotic by visual inspection, had a density > 2 times that of adjacent trabecular bone, and had an attenuation of ≥250 HU. Pathological fractures, diskitis-osteomyelitis, and osteoid osteomas were excluded. Eligible cases were characterized by lesion location, maximum lesion diameter, mean density, biopsy needle type and gauge, reported complications, and histological diagnosis. Clinical and imaging follow-up was used to confirm histological diagnosis. Cases in which a benign histological diagnosis could not be confirmed by imaging over a minimum period of 1 year were excluded.

RESULTS

A total of 37 biopsies of sclerotic bone lesions met the inclusion criteria, 17 of which were performed with a power drill needle and 20 of which were performed with a manually driven needle. The mean lesion density was 604.1 HU. The overall diagnostic yield was 78.4%; overall diagnostic accuracy was 94.6%, and the false-negative rate was 5.4%. Diagnostic yield and accuracy were 82.4% and 100% respectively, with a power drill and 75% and 90% respectively, with a manual device. Diagnostic yield for lesions ≥700 HU was 90% (9 out of 10).

CONCLUSION

Densely sclerotic bone lesions are amenable to percutaneous needle biopsy.

Drilling through lateral transmuscular portal lowers the risk of suprascapular nerve injury during arthroscopic SLAP repair

PURPOSE

The aim of our study was to evaluate the risk of medial glenoid perforation and possible injury to suprascapular nerve during arthroscopic SLAP repair using lateral transmuscular portal.

METHODS

Ten cadaveric shoulder girdles were isolated and drilled at superior glenoid rim from both anterior-superior portal (1 o'clock) and lateral transmuscular portal (12 o'clock) for SLAP repairs. Drill hole depth was determined by the manufacturer's drill stop (20 mm), and any subsequent drill perforations through the medial bony surface of the glenoid were directly confirmed by dissection. The bone tunnel depth and subsequent distance to the suprascapular nerve, scapular height and width, were compared for investigated locations.

RESULTS

Four perforations out of ten (40 %) occurred through anterior-superior portal with one associated nerve injury. One perforation out of ten (10 %) occurred through lateral transmuscular portal without any nerve injury. The mean depth was calculated as 17.6 mm (SD 3) for anterior-superior portal and 26.5 mm (SD 3.6) for lateral transmuscular portal (P < 0.001).

CONCLUSIONS

It is anatomically possible that suprascapular nerve could sustain iatrogenic injury during labral anchor placement during SLAP repair. However, lateral transmuscular portal at 12 o'clock drill entry location has lower risk of suprascapular nerve injury compared with anterior-superior portal at 1 o'clock drill entry location.

Reuse of a Reversed "Bone Pad" to Perforate Incompletely Penetrated Burr Holes Created by Automatic-Releasing Cranial Perforators

BACKGROUND

It can be difficult to make complete burr holes using a perforator with automatic releasing systems in cases of a soft diploe or thick calvarial bone.

OBJECTIVE

To demonstrate the utility of a flipped "bone pad" (BP) in recovery of penetration failure when using an automatic releasing perforator.

METHODS

For craniotomy or ventricular drainage, the first step is to make 1 or more burr holes using a craniotome. Neurosurgeons sometimes incompletely penetrate the skull using the latest tools. As a countermeasure for such cases, we have developed a simple and practical method. When making a perforation using a high-speed perforator, a round bone piece we call the BP is formed just above the dura. We pulled the BP from a completed burr hole, and placed the reversed BP in position at the bottom of the incompletely perforated burr hole. The BP acted as a new hard surface, preventing the automatic releasing system from activating, and allowed the burr hole to be completed by the craniotome without the need for additional tools.

RESULTS

With this technique, we have successfully completed 6 out of 7 imperfectly perforated burr holes using a perforator with an automatic releasing system. There were no technique-related complications, such as plunging or dural laceration.

CONCLUSIONS

The method has the advantage that the BP can be obtained without drilling an additional burr hole, and can be completed without the need for increasing cost, time, or instrument usage.

Advances in Microdebrider Technology: Improving Functionality and Expanding Utility

Since its application in nasal surgery, the microdebrider has revolutionized the practice of endoscopic sinus surgery. As the demands and breadth of procedures performed endoscopically have increased, so has the need for improvement in the microdebrider and related technologies. This article addresses how use of the microdebrider has impacted endonasal surgery and discusses current advances, which include creation of specialty hand pieces and blades, increases in instrument rotational speed, incorporation of navigation and energy, adaptation for intracranial use, and disposable instrumentation designed for in office use. Advances in microdebrider technology have improved functionality and expanded the utility of these devices.

CT-guided percutaneous screw fixation plus cementoplasty in the treatment of painful bone metastases with fractures or a high risk of pathological fracture

OBJECTIVE

To evaluate the feasibility and effectiveness of computed tomography (CT)-guided percutaneous screw fixation plus cementoplasty (PSFPC), for either treatment of painful metastatic fractures or prevention of pathological fractures, in patients who are not candidates for surgical stabilization.

MATERIALS AND METHODS

Twenty-seven patients with 34 metastatic bone lesions underwent CT-guided PSFPC. Bone metastases were located in the vertebral column, femur, and pelvis. The primary end point was the evaluation of feasibility and complications of the procedure, in addition to the length of hospital stay. Pain severity was estimated before treatment and 1 and 6 months after the procedure using the visual analog scale (VAS). Functional outcome was assessed by improved patient walking ability.

RESULTS

All sessions were completed and well tolerated. There were no complications related to either incorrect positioning of the screws during bone fixation or leakage of cement. All patients were able to walk within 6 h after the procedure and the average length of hospital stay was 2 days. The mean VAS score decreased from 7.1 (range, 4-9) before treatment to 1.6 (range, 0-6), 1 month after treatment, and to 1.4 (range 0-6) 6 months after treatment. Neither loosening of the screws nor additional bone fractures occurred during a median follow-up of 6 months.

CONCLUSIONS

Our results suggest that PSFPC might be a safe and effective procedure that allows the stabilization of the fracture and the prevention of pathological fractures with significant pain relief and good recovery of walking ability, although further studies are required to confirm this preliminary experience.

Effectiveness of the surgical torque limiter: a model comparing drill- and hand-based screw insertion into locking plates

Background

The objective of this study is to analyse the effectiveness of the surgical torque limiter during operative use. The study also investigates the potential differences in torque between hand and drill-based screw insertion into locking plates using a standardised torque limiter.

Methods

Torque for both hand and power screw insertion was measured through a load cell, registering 6.66 points per second. This was performed in a controlled environment using synthetic bone, a locking plate and locking screws to simulate plate fixation. Screws were inserted by hand and by drill with torque values measured.

Results

The surgical torque limiter (1.5 Nm) was effective as the highest recorded reading in the study was 1.409 Nm. Comparatively, there is a statistically significant difference between screw insertion methods. Torque produced for manually driven screw insertion into locking plates was 1.289 Nm (95 % CI 1.269–1.308) with drill-powered screw insertion at 0.740 Nm (95 % CI 0.723–0.757).

Conclusions

The surgical torque limiter proved to be effective as per product specifications. Screws inserted under power produce significantly less torque when compared to manual insertion by hand. This is likely related to the mechanism of the torque limiter when being used at higher speeds for which it was designed. We conclude that screws may be inserted using power to the plate with the addition of a torque limiter. It is recommended that all screws inserted by drill be hand tightened to achieve adequate torque values.

Percutaneous Biopsy and Radiofrequency Ablation of Osteoid Osteoma with Excess Reactive New Bone Formation and Cortical Thickening Using a Battery-Powered Drill for Access: A Technical Note

PURPOSE

To report our experience with the use of a battery-powered drill in biopsy and radiofrequency ablation of osteoid osteoma with excess reactive new bone formation. The battery-powered drill enables obtaining the sample while drilling.

MATERIALS AND METHODS

During the last 18 months, 14 patients suffering from painful osteoid osteoma with excess reactive new bone formation underwent CT-guided biopsy and radiofrequency ablation. In order to assess and sample the nidus of the osteoid osteoma, a battery-powered drill was used. Biopsy was performed in all cases. Then, coaxially, a radiofrequency electrode was inserted and ablation was performed with osteoid osteoma protocol. Procedure time (i.e., drilling including local anesthesia), amount of scans, technical and clinical success, and the results of biopsy are reported.

RESULTS

Access to the nidus through the excess reactive new bone formation was feasible in all cases. Median procedure time was 50.5 min. Histologic verification of osteoid osteoma was performed in all cases. Radiofrequency electrode was coaxially inserted within the nidus and ablation was successfully performed in all lesions. Median amount CT scans, performed to control correct positioning of the drill and precise electrode placement within the nidus was 11. There were no complications or material failure reported in our study.

CONCLUSIONS

The use of battery-powered drill facilitates access to the osteoid osteoma nidus in cases where excess reactive new bone formation is present. Biopsy needle can be used for channel creation during the access offering at the same time the possibility to extract bone samples.