Application of three-dimensional printed biomodels in endoscopic spinal surgery.

Background: Three-dimensional printing (3DP) is increasingly used to individualise surgery and may be an effective tool for representing patient anatomy. Current literature on patient-specific anatomical models (biomodels) for minimally invasive spinal surgery is a limited number of case series and cohort studies. However, studies investigating 3DP in other specialties have reported multiple benefits. Methods: This prospective study considered a series of patients (n=33) undergoing elective endoscopic spinal surgery, including combinations of microdiscectomy (n=27), foraminotomy (n=7), and laminectomy (n=3). These surgeries were conducted at vertebral levels ranging from L2/3 to L5/S1. The surgeon then recorded the impact on preoperational planning, intraoperative decision-making and accelerating the learning curve with a qualitative questionnaire. Results: There were benefits to planning in 54.5% of cases (n=18), improved intraoperative decision-making in 60.6% of cases (n=20). These benefits were reported more frequently earlier in the cases, with improvements to learning reported in 60% of the first five cases and not in subsequent cases. The surgeon commented that the biomodels were more useful on. Conclusions: The rates of preoperative and intraoperative benefits are consistent with existing studies, and the early benefit to the learning curve may be suitable for applications to surgical training. Additional research is required to determine the practicality of biomodels and their impact on patient outcomes for endoscopic spinal surgery.

The use of carbon fiber/polyetheretherketone (CF/PEEK) in pedicle screw fixation for spinal neoplasms-potential advantages in postoperative imaging and radiotherapy planning.

Background: Titanium pedicle screw fixation complicates postoperative care in patients with spinal neoplasms due to postoperative imaging artefacts and dose perturbation. This study aims to measure the benefits of using carbon fiber/polyetheretherketone (CF/PEEK) pedicle fixation compared to titanium in postoperative imaging, radiotherapy planning and delivery for spinal neoplasms treated with conventional external beam radiotherapy with a commercial treatment planning system. Methods: The properties of CF/PEEK pedicle fixation systems were compared to titanium in radiotherapy dose planning accuracy and postoperative computed tomography (CT) image quality. Dose profiles through the screw, tulip and longitudinal axis of the screw were acquired with radiochromic films and compared to a collapsed cone algorithm simulation, to measure dose agreement. The image quality of postoperative CTs were compared by defining four regions of interest around the vertebrae and screws in water phantom models and previous planning CTs, and comparing calculated artefact indexes (AIs). Results: CF/PEEK screws have non-inferior dosimetric prediction accuracy up to 50 mm beneath the screw for collapsed-cone algorithm planning systems. There is a statistically significant reduction in the absolute difference between calculated and measured dose at a depth of 2 mm beneath the screw. There is minimal attenuation with CF/PEEK relative to the surrounding dose, extending to 50 mm beneath the screw. There is a statistically significant improvement in CT imaging quality with reduced AIs in CF/PEEK fixation compared to titanium in both model and patient CT plans. Conclusions: CF/PEEK pedicle fixation can provide benefits in postoperative imaging and photon radiotherapy planning and delivery to patients with spinal neoplasms.

The subjective and objective quality of life score (SOQOLTM) for the quantification of general health status: a preliminary study with initial normative population values.

BACKGROUND: Established health-related quality of life scores do not consider both subjective and objective indices of health. We propose the subjective and objective quality of life score (SOQOL) for the comprehensive assessment of health-related quality of life and aim to provide normative population data. The SOQOL is compatible with smartphone applications, allowing widespread use on a global scale. METHODS: Normative SOQOL population data was sourced from pre-existing datasets on the EQ-5D-5L, daily step count, and walking speed. Normative values were calculated using weighted grand means. We trialled the SOQOL in a group of five patients presenting to a spinal neurosurgery clinic. RESULTS: SOQOL scores decreased with age, and women had lower scores in every age group. In our case series, the spine patients with the biggest SOQOL deficit compared to age- and sex-matched population averages were found to be surgical while the rest were non-surgical. CONCLUSIONS: The SOQOL shows promise as a simple and effective scoring tool that is compatible with smartphones, potentially useful for screening in primary and specialized care settings, and for assessment following healthcare interventions. This study, however, is preliminary, and the findings are primarily suggestive. They underline the necessity for future, more comprehensive studies to validate and expand upon these initial observations. The conclusion of both this abstract and the full paper will clearly state these limitations and the preliminary nature of the study.

Challenges of conducting a randomised placebo-controlled trial of spinal surgery: the SUcceSS trial of lumbar spine decompression.

Although placebo-controlled trials are considered the gold standard for evaluating the efficacy of healthcare interventions, they can be perceived to be controversial and challenging to conduct for surgical treatments. The SUcceSS trial is the first placebo-controlled trial of lumbar decompression surgery for symptomatic lumbar canal stenosis. The SUcceSS trial has experienced common issues affecting the implementation of randomised placebo-controlled surgery trials, accentuated by the COVID-19 pandemic. Using the SUcceSS trial as an example, we discuss key challenges and mitigation strategies specific to the conduct of a randomised placebo-controlled surgical trial. Overall, the key lessons learned were (i) involving key stakeholders early and throughout the trial design phase may increase clinician and patient willingness to participate in a placebo-controlled trial of surgical interventions, (ii) additional resources (e.g. budget, staff time) are likely required to successfully operationalise trials of this nature, (iii) the level of placebo fidelity, timing of randomisation relative to intervention delivery, and nuances of the surgical procedure under investigation should be considered carefully. Findings are based on one example of a placebo-controlled surgical trial; however, researchers may benefit from employing or building from the strategies described and lessons learned when designing or implementing future trials of this nature.

Continuous data capture of gait and mobility metrics using wearable devices for postoperative monitoring in common elective orthopaedic procedures of the hip, knee, and spine: a scoping review.

BACKGROUND: Surgical procedures involving the hip, knee, or spine represent a majority of orthopaedic procedures performed electively in the health care system. Postoperative care is a key aspect of surgery and mobilisation without injury is the primary objective. Recent advances in wearable technologies allow objective evaluation of walking metrics to inform and guide postoperative care following orthopaedic surgery. PURPOSE: The aim of this scoping review is to explore current applications of wearable devices, objective data capture and gait analysis in monitoring postoperative recovery following commonly performed elective orthopaedic procedures of the hip, knee and spine. METHODS: A search against pre-defined criteria was performed on the following scientific databases from date of inception to February 28th, 2021: Medline (via OvidSP), Embase (via OvidSP) and Cochrane Library (via CENTRAL). Data were collected according to a predetermined checklist including study participants, surgery, wearable device (model), sensor location, and monitoring parameters such as mobility metrics, monitoring timepoints and monitoring duration for each study included in our review. Quality was assessed independently using the Newcastle Ottawa Scale (NOS). CONCLUSIONS: To our knowledge, this is the first review of wearable monitoring (of postoperative recovery) following hip, knee and spine surgery. Patients undergoing elective orthopaedic procedures may benefit from wearable monitoring of their walking health and mobility metrics.

Clinical gait characteristics in the early post-concussion phase: A systematic review.

BACKGROUND: Understanding gait alterations immediately post-concussion can improve identification, management and prognosis of concussion. OBJECTIVE: To identify and define gait characteristics immediately post-concussion. METHOD: A review of electronic databases was conducted using terms gait alteration AND mTBI OR concussion. 172 reports were identified. After restricting to English and human studies, 158 remained. Reports were screened to include studies assessing quantifiable gait change post-concussion. 12 studies were included. DISCUSSION: Multiple gait features are altered post-impact: stability, step length, walking speed and postural control. There is evidence that postural measures in gait initiation and termination may identify more subtle deficits. There is paucity of data evaluating the impact of concussion on gait function acutely and the authors identified no studies examining immediate changes. CONCLUSION: Acutely post-concussion, various gait alterations are seen and correlate with degree of deficit and prognosis. Slowed gait, instability and postural control are several features. Dynamic gait and postural assessments identify more subtle gait alterations. Given the absence in literature, high quality prospective studies examining immediate gait alterations post-concussion would contribute to improved assessment, management and prognostication. Given difficulty in participant recruitment, technological and standardised gait assessments should be used to assess force of impact and immediate gait alteration.

Australian Spine Surgeon's Perspectives on Endoscopic Spine Surgery: An In-depth Analysis.

OBJECTIVE: Endoscopic spine surgery (ESS) is a minimally invasive approach with reduced tissue trauma, shorter hospital stays, and faster recovery times. It employs advanced endoscopic instruments and imaging technologies to address a wide range of spinal pathologies with minimal disruption to surrounding tissues. As ESS continues to evolve, this article aims to gather insights into the opinions and perspectives of the key stakeholders involved, and highlight strategies to improve implementation. METHODS: A cross-sectional survey was distributed to collect data on Australian spine surgeons' perspectives of ESS. The survey questionnaire was distributed electronically to a diverse group of spine surgeons who are members of the Spine Society of Australia. RESULTS: Of responders, 46.8% were already integrating ESS into practice, or had the sufficient training to commence ESS. A further 29.8% were contemplating introduction of ESS techniques, while just under one quarter of respondents (23.4%) were not interested in implementing minimally invasive techniques. Primary motivators for implementation included skill development and improved patient outcomes. Primary barriers included lack of training opportunities, length of time to develop competency and lack of current supporting evidence. CONCLUSION: The study contributes to the existing body of knowledge on ESS by providing a comprehensive analysis of surgeon opinions and experiences. The results highlight the growing interest in endoscopic techniques, while recognizing the challenges that need to be addressed to make this more widely utilised and available. The findings can guide future research, training programs, clinical practice and ultimately improve health and financial outcomes to patients and the wider health system.

Proposed objective scoring algorithm for clinical evaluation of walking asymmetry in lumbar disc herniation, based on relevant gait metrics from wearable devices: The Gait Symmetry Index (GSiTM) - Observational study.

•The proposed GSi algorithm aims to objectively evaluate the walking impairment associated with lumbar disc herniation (LDH).•GSi is calculated as deviation from mean (age-matched) normative values for gait velocity, step time asymmetry and step length asymmetry.•Clinical performance was assessed in a prospective, single surgeon series of 33 lumbar disc herniation (LDH) patients.•GSi was lower in LDH participants with significant distribution between surgical and conservative management subgroups.

The concept of recovery kinetics: an observational study of continuous post-operative monitoring in spine surgery.

Background: The spine surgeon's understanding of an individual patient's burden of disease and functional disability in daily life is shaped by patient-reported outcome measures (PROMs). Although PROMs are useful in understanding the patient's perception of their disease, the use of PROMs constitutes a "snapshot" approach of single timepoint data capture, omitting day-to-day fluctuations in functional status. We introduce the concept of kinetics when considering continuous and objective postoperative patient monitoring with wearable sensors. Methods: A prospective single-centre series was performed using patients either undergoing lumbar decompression for lumbar spinal stenosis (LSS) (n=12), or posterior lumbar fusion for degenerative spondylolisthesis (n=12). The Oswestry Disability Index (PROM) was conducted preoperatively and 12-weeks postoperatively. During this timeframe, continuous measurements of step count and distance travelled were made using a wrist-based wearable accelerometer. Results: Over the 12-week study period, mean daily step count for all participants improved from 4,700 to 7,700 steps per day (P=0.013), following an initial dip in total steps taken. The mean daily distance travelled improved from 3,300 to 5,300 meters per day (P=0.003). Decompression group recovered at a faster rate than the fusion group. Conclusions: Although overall improvement was similar between the decompression and fusion groups, the recovery kinetics varied. The recovery kinetics approach of continuous postoperative monitoring provides additional insight to postoperative patient progress.

Rapid Personalised Virtual Planning and On-Demand Surgery for Acute Spinal Trauma Using 3D-Printing, Biomodelling and Patient-Specific Implant Manufacture.

Three-dimensional printing is a rapidly growing field, with extensive application to orthopaedics and spinal surgery. Three-dimensional-printed (3DP) patient-specific implants (PSIs) offer multiple potential benefits over generic alternatives, with their use increasingly being described in the spinal literature. This report details a unique, emergency case of a traumatic spinal injury in a 31-year-old male, acquired rurally and treated with a 3DP PSI in a tertiary unit. With increasing design automation and process improvements, rapid, on-demand virtual surgical planning (VSP) and 3DP PSIs may present the future of orthopaedics and trauma care, enabling faster, safer, and more cost-effective patient-specific procedures.

Analysing gait patterns in degenerative lumbar spine diseases: a literature review.

Objectives: To collate the current state of knowledge and explore differences in the spatiotemporal gait patterns of degenerative lumbar spine diseases: lumbar spinal stenosis (LSS), lumbar disc herniation (LDH) and low back pain (LBP). Background: LBP is common presenting complaint with degenerative lumbar spine disease being a common cause. In particular, the gait patterns of LSS, LDH and mechanical-type (facetogenic and discogenic) LBP is not established. Methods: A search of the literature was conducted to determine the changes in spatial and temporal gait metrics involved with each type of degenerative lumbar spine disease. A search of databases including Medline, Embase and PubMed from their date of inception to April 18th, 2021 was performed to screen, review and identify relevant studies for qualitative synthesis. Seventeen relevant studies were identified for inclusion in the present review. Of these, 5 studies investigated gait patterns in LSS, 10 studies investigated LBP and 2 studies investigated LDH. Of these, 4 studies employed wearable accelerometry in LSS (2 studies) and LBP (2 studies). Conclusions: Previous studies suggest degenerative diseases of the lumbar spine have unique patterns of gait deterioration. LSS is characterised by asymmetry and variability. Spatiotemporal gait deterioration in gait velocity, cadence with increased double-support duration and gait variability are distinguishing features in LDH. LBP involves marginal abnormalities in temporal and spatial gait metrics. Previous studies suggest degenerative diseases of the lumbar spine have unique patterns of gait deterioration. Gait asymmetry and variability, may be relevant metrics for distinguishing between the gait profiles of lumbar spine diseases.

Validation of a novel range of motion assessment tool for the cervical spine: the HALO© digital goniometer.

Background: Cervical spine range of motion (ROM) assessment has long been carried out via use of the universal goniometer (UG) as an objective tool in the evaluation of patient rehabilitation pre- and post-operatively. The advent of novel ROM assessment technology, such as HALO digital goniometer (DG), presents an avenue for research and potential application within clinical and surgical settings. The objective of this study was to examine the reliability and validity of the HALO DG in the assessment of the active ROM of the cervical spine. Methods: One hundred healthy subjects were recruited for the study and were split into two groups to be assessed by either physiotherapists or medical students. The methodology for cervical spine ROM assessment was carried out per the American Association of Orthopaedic Surgeons (AAOS) guidelines. The reliability analysis was completed using IBM SPSS Statistics 25, calculating the intraclass correlation coefficients (ICC) to determine both the intra- and inter-rater reliability of the device. Results: Inter-rater reliability within the physiotherapist cohort with the DG (ICCr =0.477, 0.718, 0.551) was higher compared to the UG (ICCr =0.380, 0.510, 0.255) for active cervical flexion, lateral flexion, and rotation, respectively. The UG (ICCr =0.819) showed better reliability versus the DG (ICCr =0.780) when assessing cervical extension. Similarly, in the medical student cohort, the DG outperformed the UG in all movement except cervical lateral flexion. When assessing for intra-rater reliability, the DG (ICCm =0.507, 0.773, 0.728, 0.691) performed better than the UG (ICCm =0.487, 0.529, 0.532, 0.585) in cervical flexion, extension, lateral flexion, and rotation, respectively. Conclusions: The present validation study identified the DG as a reliable substitute for the UG.

Tracking the disease progression of lumbar spinal stenosis using objective gait metrics: a case report.

We present the case of an 85-year-old woman who presented to our clinic with neurogenic claudication due to lumbar spinal stenosis (LSS) over a period of two years. During this time a series of walking metrics were monitored including daily step count, walking speed, and step length. All metrics showed a deterioration over time and objectively document the disease progression of LSS (initial: walking speed =1.03 m/s, step length =0.49 m, and daily step count =3,136; final: walking speed =0.49 m/s, step length =0.37 m, and daily step count =334). At this time, the patient had also begun experiencing bilateral lower limb weakness and paraesthesia upon exertion, preventing her from mobilizing for more than a few meters at a time. After a shared decision-making process with the patient and her family, surgical management was recommended. The deterioration of the patient's walking metrics matched their increasing requirement for walking assistance, with no walking assistance being needed initially, compared to a four-wheel walker being required in the weeks prior to her surgery. Therefore, the extent of walking deterioration may be able to inform clinical decision-making regarding appropriate walking assistance. To our knowledge, this is the first report that objectively documents the deterioration of LSS using walking metrics for such a prolonged duration of time.

Two-year continuous data capture using a wearable sensor to remotely monitor the surgical spine patient: a case report.

We report the case of a 46-year-old male with long-standing low back pain who presented with a deterioration of symptoms characterised by back and right leg pain corresponding to the L4 and L5 dermatomes. An MRI scan revealed severe central and lateral recess stenosis at L4/5 secondary to a large central disc protrusion. We remotely monitored activity and general health metrics over a time-period exceeding two years. This is the first study to monitor these metrics remotely and continuously in the surgical spine patient. Over this time, he received several interventions including a spinal cord stimulator implant, and an L4/5 microdiscectomy. We tracked his fluctuating health status using the Oura Ring [objectively measuring metrics including step count, sleep patterns, heart rate (HR), heart-rate variability (HRV), and respiratory rate (RR)] and with daily self-reported scores on the Visual Analogue Scale. The Oura Ring is a convenient and lightweight wearable device that is worn on any finger. Taken together, metrics provided a comprehensive picture of deterioration and recovery, paralleling key events in the patient's history. The use of wearable devices is feasible in enabling long-term remote continuous monitoring. This may assist surgeons and rehabilitation providers in identifying early deterioration and monitoring the post-intervention course of recovery.

Standalone titanium/polyetheretherketone interbody cage for anterior lumbar interbody fusion: Clinical and radiological results at 24 months.

Context: Anterior lumbar interbody fusion (ALIF) is a common procedure for patients suffering degenerative, deformity, or posttraumatic pathologies of the lumbar spine. Aims: The aim of this study is to evaluate the clinical and radiological outcomes of a combination Titanium/Polyetheretherketone (Ti/PEEK) 3-screw fixation ALIF cage. Settings and Design: This was a prospective multisurgeon series of 87 patients (105 implants), with a minimum 24-month follow-up. Twelve patients (12/87) were supplemented with posterior percutaneous pedicle screw fixation for additional stability for pars defect spondylolisthesis correction. Radiological follow-up with fine-cut computed tomography (CT) scan occurred at 4-6 months, and again at 18-24 months if no fusion observed on initial CT, was performed to evaluate early and final fusion rates, and integration of the Ti/PEEK cage at the end-plate junction. Clinical follow-up included the subjective measures of pain and functional status and objective wearable device monitoring. Results: The fusion rate was 85% (97/105 implants) 6 months postoperatively, with no implant-related complications, and 95% at 24 months, based on independent radiological assessment. Patients experienced statistically significant improvement in subjective pain and functional outcomes compared to preoperative status. The objective measures revealed a daily step count with a 27% improvement, and gait velocity with a mean increase from 0.97 m/s to 1.18 m/s, at 3 months postoperatively. Conclusions: A Ti/PEEK cage, with allograft and bone morphogenetic protein-2 (BMP-2), achieved rapid interbody progression to fusion and is an effective implant for use in anterior lumbar surgery with high early fusion rates and no peri-endplate lucency. Supercritical CO2 allograft provided an osteoconductive scaffold and combined well with BMP-2 to facilitate fusion.

Comparison of in vivo kinematic and radiological parameters of three cervical disc prostheses.

Introduction: Cervical total disc replacement (CTDR) is an alternative to anterior cervical discectomy and fusion for select patients that may preserve range of motion and reduce adjacent segment disease. Various CTDR prostheses are available; however, comparative data are limited. This study aimed to compare the short-term kinematic and radiological parameters of the M6-C, Mobi-C, and the CP-ESP prostheses. Methods: This retrospective cohort study included patients treated with CTDR between March 2005 and October 2020 at a single institution. Patients were included if their follow-up assessment included lateral erect and flexion/extension radiographs. The primary outcome assessed at 3-months postoperatively was range of motion, measured by the difference in functional spinal unit angle between flexion and extension. Results: A total of 131 CTDR levels (120 patients, 46.2 ± 10.1 years, 57% male) were included. Prostheses implanted included the M6-C (n = 52), Mobi-C (n = 54), and CP-ESP (n = 25). Range of motion varied significantly (8.2° ± 4.4° vs. 10.9° ± 4.7° vs. 6.1° ± 2.7°, P < 0.001). On post hoc analysis, the Mobi-C prosthesis demonstrated a significantly greater range of motion than either the M6-C prosthesis (P = 0.003) or CP-ESP (P < 0.001). Conclusion: Although the optimal range of motion for CTDR has not been established, short-term differences in the range of motion may guide the selection of CTDR prosthesis. Further studies with longer follow-up and consideration of clinical outcome measures are necessary.