Interbody Fusion Techniques in the Surgical Management of Degenerative Lumbar Spondylolisthesis

Purpose of Review

The various lumbar interbody fusion (IBF) techniques and the evidence for their use in the treatment of degenerative lumbar spondylolisthesis (DLS) are described in this review.

Recent Findings

The existing evidence is mixed regarding the indications for and utility of IBF in DLS, but its use in the setting of pre-operative instability is most strongly supported. Anterior (ALIF), lateral (LLIF), posterior (PLIF), transforaminal (TLIF), and axial (AxiaLIF) lumbar IBF approaches have been described. While the current data are limited, TLIF may be a better option than PLIF in DLS due the increased operative morbidity and peri-operative complications observed with the latter. LLIF also appears superior to PLIF in light of improved radiologic outcomes, fewer intra-operative complications, and potentially greater improvements in disability. The data comparing LLIF to TLIF are less conclusive. No studies specifically comparing ALIF or AxiaLIF to other IBF techniques could be identified.

Summary

Instability may be the strongest indication for IBF in DLS. When IBF is employed, the authors’ preferred technique is TLIF with posterior segmental spinal instrumentation. Further research is needed.

     

Degenerative Scoliosis

Purpose of Review

The purpose of this review is to provide an updated review of adult degenerative scoliosis (ADS). Epidemiology, classification, pathophysiology, and natural history are discussed along with a summary of commonly used outcome measures. Operative vs non-operative outcomes and new surgical techniques are discussed.

Recent Findings

The SRS-Schwab classification (2012) combines clinical and radiographic evaluation including overall global alignment. Current evidence regarding risk factors and efficacy of non-surgical modalities are discussed. Recent studies have reported surgical management to provide superior outcomes to non-operative modalities. New surgical techniques provide promising early data in regard to decreasing perioperative morbidity.

Summary

ADS is a potentially debilitating condition that occurs with asymmetric spinal degeneration. This can produce global sagittal malalignment and central and foraminal stenosis and can lead to significant impairment often necessitating surgery. The surgeon must be aware of the perioperative risks in this population and implement appropriate age-specific alignment goals to achieve the best outcome for patients.

     

Lumbar disc replacement surgery—successes and obstacles to widespread adoption

Purpose of review

Lumbar disc replacement has been a surgical alternative to fusion surgery for the treatment of lumbar degenerative disc disease (DDD) for many years. Despite enthusiasm after the approval of the first devices, implantation rates have remained low, especially in the USA. The goal of this review is to provide a general overview of lumbar disc replacement in order to comprehend the successes and obstacles to widespread adoption.

Recent findings

Although a large amount of evidence-based data including satisfactory long-term results is available, implantation rates in the USA have not increased in the last decade. Possible explanations for this include strict indications for use, challenging surgical techniques, lack of device selection, fear of late complications or revision surgeries, and reimbursement issues.

Summary

Recent publications can address some of the past concerns, but there still remain obstacles to widespread adoption. Upcoming data on long-term outcome, implant durability and possible very late complications will determine the future of lumbar disc replacement surgery.

     

Offene Arthrolyse des Kniegelenks

Background

Loss of range of motion of the knee joint causes significant disability. Surgical treatment should include arthroscopic as well as open arthrolysis procedures.

Objectives

Impairments of extension and flexion can have capsular or extra-articular origins in the musculature. The techniques of open capsulotomy and interventions on the proximal and distal extension apparatus are presented.

Methods

Discussion on the indications and surgical techniques for open arthrolysis of the knee joint are presented based on own results and the available literature.

Results

The established surgical techniques can significantly improve the range of motion considering the severity of this case group.

Conclusions

An exact analysis of the cause of knee stiffness is necessary. Only intra-articular problems can be arthroscopically treated and open techniques are indicated when the stiffness is caused by an extra-articular pathology. The techniques are established and reproducible.

     

Surgical process analysis identifies lack of connectivity between sequential fluoroscopic 2D alignment as a critical impediment in femoral intramedullary nailing

Purpose

Identifying key steps and barriers within complex and simple surgical procedures can be accomplished in a structured and rigorous manner using surgical process modeling. For lower extremity long bone fracture stabilization, the current standard of care is closed intramedullary (IM) nailing, which, despite its widespread use, is associated with challenges that greatly impact operative time and lead to the frustration of medical staff. The aim of this study was to identify challenging surgical steps in IM nailing and understand their underlying causation.

Methods

Eight semi-structured interviews with staff orthopedic surgeons and eight detailed surgical observations were conducted to understand the surgical steps, challenges and adapted techniques used in IM nailing. Hierarchical decomposition was then utilized to structure the IM nailing surgical procedure into phases, steps and activities.

Results

In the developed IM nailing surgical process model, the most challenging steps were identified as fracture reduction (75 %) and entry point selection (25 %), both of which were associated with high levels of frustration in the observed surgeries. Both of these steps utilize 2D fluoroscopic imaging to guide 3D alignment. Challenges arise when the alignment in one plane is lost while adjusting the alignment in the perpendicular plane. This leads to unpredictable repetition of activities which can be time-consuming and frustrating.

Conclusion

Identifying the causation of surgical challenges in IM nailing through surgical process modeling forms a knowledge base that can be used to guide future improvements to techniques and surgical instrumentation.

     

Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction

Purpose

Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction.

Recent findings

Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics.

Summary

Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

     

Development of preoperative planning software for transforaminal endoscopic surgery and the guidance for clinical applications

Purpose

Preoperative planning is of great importance for transforaminal endoscopic techniques applied in percutaneous endoscopic lumbar discectomy. In this study, a modular preoperative planning software for transforaminal endoscopic surgery was developed and demonstrated.

Methods

The path searching method is based on collision detection, and the oriented bounding box was constructed for the anatomical models. Then, image reformatting algorithms were developed for multiplanar reconstruction which provides detailed anatomical information surrounding the virtual planned path. Finally, multithread technique was implemented to realize the steady-state condition of the software.

Results

A preoperative planning software for transforaminal endoscopic surgery (TE-Guider) was developed; seven cases of patients with symptomatic lumbar disc herniations were planned preoperatively using TE-Guider. The distances to the midlines and the direction of the optimal paths were exported, and each result was in line with the empirical value.

Conclusions

TE-Guider provides an efficient and cost-effective way to search the ideal path and entry point for the puncture. However, more clinical cases will be conducted to demonstrate its feasibility and reliability.

     

An augmented reality C-arm for intraoperative assessment of the mechanical axis: a preclinical study

Background

Determination of lower limb alignment is a prerequisite for successful orthopedic surgical treatment. Traditional methods include the electrocautery cord, alignment rod, or axis board which rely solely on C-arm fluoroscopy navigation and are radiation intensive.

Study objectives

To assess a new augmented reality technology in determining lower limb alignment.

Methods

A camera-augmented mobile C-arm (CamC) technology was used to create a panorama image consisting of hip, knee, and ankle X-rays. Twenty-five human cadaver legs were used for validation with random varus or valgus deformations. Five clinicians performed experiments that consisted in achieving acceptable mechanical axis deviation. The applicability of the CamC technology was assessed with direct comparison to ground-truth CT. A t test, Pearson’s correlation, and ANOVA were used to determine statistical significance.

Results

The value of Pearson’s correlation coefficient R was 0.979 which demonstrates a strong positive correlation between the CamC and ground-truth CT data. The analysis of variance produced a p value equal to 0.911 signifying that clinician expertise differences were not significant with regard to the type of system used to assess mechanical axis deviation.

Conclusion

All described measurements demonstrated valid measurement of lower limb alignment. With minimal effort, clinicians required only 3 X-ray image acquisitions using the augmented reality technology to achieve reliable mechanical axis deviation.

     

Olanzapine vs haloperidol: treating delirium in a critical care setting

Objective

To compare the safety and estimate the response profile of olanzapine, a second-generation antipsychotic, to haloperidol in the treatment of delirium in the critical care setting.

Design

Prospective randomized trial

Setting

Tertiary care university affiliated critical care unit.

Patients

All admissions to a medical and surgical intensive care unit with a diagnosis of delirium.

Interventions

Patients were randomized to receive either enteral olanzapine or haloperidol.

Measurements

Patient’s delirium severity and benzodiazepine use were monitored over 5 days after the diagnosis of delirium.

Main results

Delirium Index decreased over time in both groups, as did the administered dose of benzodiazepines. Clinical improvement was similar in both treatment arms. No side effects were noted in the olanzapine group, whereas the use of haloperidol was associated with extrapyramidal side effects.

Conclusions

Olanzapine is a safe alternative to haloperidol in delirious critical care patients, and may be of particular interest in patients in whom haloperidol is contraindicated.

     

Minimalinvasive Schmerztherapie rund um die Wirbelsäule

Background

Spinal pain is common and often difficult to treat. In addition to the individual’s impairment, the economic damage is also enormous.

Objective

The present work aims to provide an overview of therapeutic procedures commonly used to treat spinal pain today. These methods are employed primarily for therapy-resistant pain without an existing surgical indication.

Materials and methods

The existing literature was reviewed using PubMed, Google Scholar, and orthopedic textbooks. Further references to older literature were investigated using the Google search function and the Central Library of the Medical University of Vienna.

Results

In addition to X?ray-targeted infiltration, neuroablative and neuromodulatory procedures as well as adhesiolysis catheters are available. They provide consistently good results if correctly indicated.

Discussion

Although in many patients, given the complexity of the pain, complete freedom from symptoms is hardly realistic, the constantly evolving minimally invasive procedures enable a clinically relevant pain reduction to be achieved. Due to the low tissue traumatization there is hardly any scar formation, and the risks of the interventions are low if correctly performed.

     

A mixed-reality surgical trainer with comprehensive sensing for fetal laser minimally invasive surgery

Purpose

Smaller incisions and reduced surgical trauma made minimally invasive surgery (MIS) grow in popularity even though long training is required to master the instrument manipulation constraints. While numerous training systems have been developed in the past, very few of them tackled fetal surgery and more specifically the treatment of twin-twin transfusion syndrome (TTTS). To address this lack of training resources, this paper presents a novel mixed-reality surgical trainer equipped with comprehensive sensing for TTTS procedures. The proposed trainer combines the benefits of box trainer technology and virtual reality systems. Face and content validation studies are presented and a use-case highlights the benefits of having embedded sensors.

Methods

Face and content validity of the developed setup was assessed by asking surgeons from the field of fetal MIS to accomplish specific tasks on the trainer. A small use-case investigates whether the trainer sensors are able to distinguish between an easy and difficult scenario.

Results

The trainer was deemed sufficiently realistic and its proposed tasks relevant for practicing the required motor skills. The use-case demonstrated that the motion and force sensing capabilities of the trainer were able to analyze surgical skill.

Conclusion

The developed trainer for fetal laser surgery was validated by surgeons from a specialized center in fetal medicine. Further similar investigations in other centers are of interest, as well as quality improvements which will allow to increase the difficulty of the trainer. The comprehensive sensing appeared to be capable of objectively assessing skill.

     

Knowledge transfer for surgical activity prediction

Purpose

Lack of annotated training data hinders automatic recognition and prediction of surgical activities necessary for situation-aware operating rooms. We propose using knowledge transfer to compensate for data deficit and improve prediction.

Methods

We used two approaches to extract and transfer surgical process knowledge. First, we encoded semantic information about surgical terms using word embedding. Secondly, we passed knowledge between different clinical datasets of neurosurgical procedures using transfer learning.

Results

The combination of two methods provided 22% improvement of activity prediction. We also made several pertinent observations about surgical practices based on the results of the performed transfer.

Conclusion

Word embedding boosts learning process. Transfer learning was shown to be more effective than a simple combination of data, especially for less similar procedures.

     

Accuracy analysis in MRI-guided robotic prostate biopsy

Purpose

To assess retrospectively the clinical accuracy of an magnetic resonance imaging-guided robotic prostate biopsy system that has been used in the US National Cancer Institute for over 6 years.

Methods

Series of 2D transverse volumetric MR image slices of the prostate both pre (high-resolution T2-weighted)- and post (low-resolution)- needle insertions were used to evaluate biopsy accuracy. A three-stage registration algorithm consisting of an initial two-step rigid registration followed by a B-spline deformable alignment was developed to capture prostate motion during biopsy. The target displacement (distance between planned and actual biopsy target), needle placement error (distance from planned biopsy target to needle trajectory), and biopsy error (distance from actual biopsy target to needle trajectory) were calculated as accuracy assessment.

Results

A total of 90 biopsies from 24 patients were studied. The registrations were validated by checking prostate contour alignment using image overlay, and the results were accurate to within 2 mm. The mean target displacement, needle placement error, and clinical biopsy error were 5.2, 2.5, and 4.3 mm, respectively.

Conclusion

The biopsy error reported suggests that quantitative imaging techniques for prostate registration and motion compensation may improve prostate biopsy targeting accuracy.

     

3D ultrasound registration-based visual servoing for neurosurgical navigation

Purpose

We present a fully image-based visual servoing framework for neurosurgical navigation and needle guidance. The proposed servo-control scheme allows for compensation of target anatomy movements, maintaining high navigational accuracy over time, and automatic needle guide alignment for accurate manual insertions.

Method

Our system comprises a motorized 3D ultrasound (US) transducer mounted on a robotic arm and equipped with a needle guide. It continuously registers US sweeps in real time with a pre-interventional plan based on CT or MR images and annotations. While a visual control law maintains anatomy visibility and alignment of the needle guide, a force controller is employed for acoustic coupling and tissue pressure. We validate the servoing capabilities of our method on a geometric gel phantom and real human anatomy, and the needle targeting accuracy using CT images on a lumbar spine gel phantom under neurosurgery conditions.

Results

Despite the varying resolution of the acquired 3D sweeps, we achieved direction-independent positioning errors of \(0.35\pm 0.19\) mm and \(0.61^\circ \pm 0.45^\circ \), respectively. Our method is capable of compensating movements of around 25 mm/s and works reliably on human anatomy with errors of \(1.45\pm 0.78\) mm. In all four manual insertions by an expert surgeon, a needle could be successfully inserted into the facet joint, with an estimated targeting accuracy of \(1.33\pm 0.33\) mm, superior to the gold standard.

Conclusion

The experiments demonstrated the feasibility of robotic ultrasound-based navigation and needle guidance for neurosurgical applications such as lumbar spine injections.

     

Zellfreie Biomaterialien

Introduction

Regenerative scaffold-based procedures are emerging as a potential therapeutic option for the treatment of chondral and osteochondral lesions. In vitro studies, preclinical studies and clinical applications are of great interest with an increasing number of publications every year.

Methods

One-step strategies with cell-free scaffolds have recently been developed to broaden the indications, simplify the procedure and further reduce costs.

Results and conclusion

Clinical application has been reported for different types of scaffold at short and medium-term follow-up but well-designed studies are lacking. Systematic long-term evaluation of these techniques and randomized controlled studies are necessary to confirm the potential of this tissue engineering approach, especially compared with the available traditional forms of treatment.

     

Predictive factors for polypharmacy among child and adolescent psychiatry inpatients

Background

Aim was to determine the predictive factors for polypharmacy among inpatient children and adolescents with psychiatric disorders.

Methods

Blinded, case-note review of children and adolescents with ICD 10 diagnosis of psychiatric disorders on psychotropic medication was conducted. Data on demography, illness, and treatment was analyzed with univariate and multivariate techniques.

Results

Proscribing non-pharmacological interventions (OR = 4.7) and pro re nata medication (OR = 3.3), increased the risk of polypharmacy. Prescribing physical restraint reduced the risk of receiving multiple medications (OR = 0.3).

Conclusion

Proscribing non-pharmacological interventions, pro re nata medication and physical restraints increased polypharmacy.

     

Low dose quetiapine induced galactorrhoea: a case report

Background

Quetiapine causes less prolactin elevation and/or galactorrhoea than other atypical antipsychotics.

Case Presentation

Ms AB had galactorrhoea and raised prolactin levels at only 100 mg of quetiapine daily.

Conclusion

Low dose quetiapine can also cause galactorrhoea.

     

Treatment for Degenerative Lumbar Spondylolisthesis: Current Concepts and New Evidence

Purpose of Review

Current guidelines for the optimal treatment degenerative spondylolisthesis are weak and based on limited high-quality evidence.

Recent Findings

There is some moderate evidence that decompression alone may be a feasible treatment with lower surgical morbidity and similar outcomes to fusion when performed in a select population with a low-grade slip. Similarly, addition of interbody fusion may be best suited to a subset of patients with high-grade degenerative spondylolisthesis, although this remains controversial. Minimally invasive techniques are increasingly being utilized for both decompression and fusion surgeries with more and more studies showing similar outcomes and lower postoperative morbidity for patients. This will likely be an area of continued intense research. Finally, the role of spondylolisthesis reduction will likely be determined as further investigation into optimal sagittal balance and spinopelvic parameters is conducted. Future identification of ideal thresholds for sagittal vertical axis and slip angle that will prevent progression and reoperation will play an important role in surgical treatment planning.

Summary

Current evidence supports surgical treatment of degenerative spondylolisthesis. While posterolateral spinal fusion remains the treatment of choice, the use of interbodies and decompressions without fusion may be efficacious in certain populations. However, additional high-quality evidence is needed, especially in newer areas of practice such as minimally invasive techniques and sagittal balance correction.

     

Surgical soundtracks: automatic acoustic augmentation of surgical procedures

Purpose

Advances in sensing and digitalization enable us to acquire and present various heterogeneous datasets to enhance clinical decisions. Visual feedback is the dominant way of conveying such information. However, environments rich with many sources of information all presented through the same channel pose the risk of over stimulation and missing crucial information. The augmentation of the cognitive field by additional perceptual modalities such as sound is a workaround to this problem. A major challenge in auditory augmentation is the automatic generation of pleasant and ergonomic audio in complex routines, as opposed to overly simplistic feedback, to avoid alarm fatigue.

Methods

In this work, without loss of generality to other procedures, we propose a method for aural augmentation of medical procedures via automatic modification of musical pieces.

Results

Evaluations of this concept regarding recognizability of the conveyed information along with qualitative aesthetics show the potential of our method.

Conclusion

In this paper, we proposed a novel sonification method for automatic musical augmentation of tasks within surgical procedures. Our experimental results suggest that these augmentations are aesthetically pleasing and have the potential to successfully convey useful information. This work opens a path for advanced sonification techniques in the operating room, in order to complement traditional visual displays and convey information more efficiently.

     

Laser-assisted flat-detector CT-guided intracranial access

Purpose

Flat-detector CT can be integrated with C-arm fluoroscopy for CT-guided neurosurgical and endovascular procedures. We studied the accuracy of this technique with laser assistance in targeting intracranial lesions in a cranial model.

Methods

An acrylic scale-model skull containing foam parenchyma was embedded with 2.16-mm-diameter targets. A flat-detector CT was acquired and registered to the skull’s position. Ten targets were accessed with biopsy needles under fluoroscopic guidance, flat-detector CT overlay, and laser assistance. Accuracy was measured from the needle tip to the target center using flat-detector CT.

Results

Ten targets were accessed successfully using XperGuide software. Needles were placed within 1.30 \(\pm \) 0.63 mm of target isocenter. Accuracy did not vary by entry site, operator, location, or lesion depth.

Conclusions

Laser-assisted flat-detector CT-guided targeting of all intracranial targets was successful with excellent accuracy. This technique can be applied to other minimally invasive neurosurgical procedures.