Ashish Diwan

UNSW Sydney | UNSW · Spine Service | Department of Orthopaedic Surgery | St George & Sutherland Clinical School | UNSW Medicine

Objective To compare the surgical trauma and outcomes between oblique lateral interbody fusion (OLIF) and posterior fixation and posterior lumbar interbody fusion (PLIF) with fixation for adult degenerative scoliosis (ADS). Methods We included ADS patients who underwent OLIF with fixation or PLIF with fixation treatment from June 2020 to December...

Purpose Increased intramedullary signal intensity (IISI) on T2 weighted MRI scan (T2WI) in patients with Degenerative Cervical Myelopathy (DCM) can be a radiological feature of spinal cord damage. However, the association of IISI to degeneration of the spinal column remains unclear in literature. The purpose of this study was to determine the preva...

Importance: Adolescent idiopathic scoliosis (AIS) is the most common pediatric spinal disorder. Routine physical examinations by trained personnel are critical to diagnose severity and monitor curve progression in AIS. In the presence of concerning malformation, radiographs are necessary for diagnosis or follow-up, guiding further management, such...

Introduction & importance Atlanto-occipital assimilation is a rare congenital abnormality which can cause atlantoaxial instability. Basilar invagination and instability can lead to cord compression and myelopathy in young individuals. Case report & discussion A 37-year-old male presented with gradually worsening axial neck pain for four years dura...

Although cigarette smoke (CS) and low back pain (LBP) are common worldwide, their correlations and the mechanisms of action remain unclear. We had shown that excessive activation of Mast Cells (MCs) and their proteases play key roles in CS associated diseases, like asthma, chronic obstructive pulmonary disease (COPD), blood coagulation and lung can...

Study Design A prospective case-control study. Objective To analyze global coronal malalignment (GCM) in degenerative lumbar scoliosis (DLS) and to prospectively investigate the performance of priority-matching correction technique on preventing postoperative coronal imbalance. Methods A total of 444 DLS inpatients and outpatients were recruited....

Introduction & Aim: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has secured a prominent role in the operative management of degenerative spinal conditions. Compared to open TLIF, minimal tissue dissection with minimal neural tissue handling and adequate decompression can be achieved with this surgery. It remains partially k...

Introduction & Aim: Any revision surgeries have poorer outcomes when compared to primary surgeries. Indications for minimally invasive transforaminal lumbar interbody fusion (MAS-TLIF) are spondylolisthesis, recurrent herniation of lumbar discs, and degenerative lumbar deformities with or without canal stenosis. The outcome of the MAS-TLIF (Nuvasi...

Current in vitro intervertebral disc (IVD) models do not fully recapitulate the complex mechanobiology of native tissue, and so far there is no strategy to effectively evaluate IVD regeneration. The development of a modular microfluidic on-chip model is expected to enhance the physiological relevance of experimental data leading to successful clini...

Most diseases of the spine disproportionately impact older persons, with the modal (i.e., commonest) patient a female in their 8th decade of life. We examined the corpus of spinal RCTs to determine how many included "average" spine patients. We searched PubMed for randomized clinical trials published in the top 7 spine journals over a period of 5 y...

Many factors may trigger intervertebral disc (IVD) structural failure (intervertebral disc degeneration (IDD) and endplate changes), including inflammation, infection, dysbiosis, and the downstream effects of chemical factors. Of these, microbial diversity in the IVD and elsewhere in the body has been considered as one of the potential reasons for...

Objective: Whilst microdiscectomy is an excellent reliever of pain for recalcitrant lumbar disc herniation (LDH), it has a high failure rate over time due to the ensuing reduction in mechanical stabilization and support of the spine. One option is to clear the disc and replace it with a nonhygroscopic elastomer. Here, we present the evaluation of...

Animal models have been invaluable in the identification of molecular events occurring in and contributing to intervertebral disc (IVD) degeneration and important therapeutic targets have been identified. Some outstanding animal models (murine, ovine, chondrodystrophoid canine) have been identified with their own strengths and weaknesses. The llama...

Extreme lateral interbody fusion (XLIF) may be performed with a standalone interbody cage, or with the addition of unilateral or bilateral pedicle screws; however, decisions regarding supplemental fixation are predominantly based on clinical indicators. This study examines the impact of posterior supplemental fixation on facet micromotions, cage lo...

There are several complications associated with lumbar interbody fusion surgery however, pseudarthrosis (non-union) presents a multifaceted challenge in the postoperative management of the patient. Rates of pseudarthrosis range from 3-20% in patients with healthy bone and 20-30% in patients with osteoporosis. The current methods in post-operative f...

BACKGROUND Routine check-ups for adolescent idiopathic scoliosis are critical to monitor progression and prescribe interventions. AIS is primarily screened via physical examination. If there are features of deformity, radiographs are necessary for diagnosis or follow-up, guiding further management, i.e., bracing corrections for moderate deformities...

The purpose of this review was to evaluate data generated by animal models of intervertebral disc (IVD) degeneration published in the last decade and show how this has made invaluable contributions to the identification of molecular events occurring in and contributing to pain generation. IVD degeneration and associated spinal pain is a complex mul...

Degenerative cervical myelopathy (DCM) manifests as the primary cause of spinal cord dysfunction and is non-traumatic, chronic and progressive in nature. Decompressive surgery is typically utilised to halt further disability and neurological dysfunction and as such, early diagnosis and assessment is a vital means of slowing the disease process. Cur...

Background: Degenerative cervical myelopathy (DCM) manifests as the primary cause of spinal cord dysfunction and is non-traumatic, chronic and progressive in nature. Decompressive surgery is typically utilised to halt further disability and neurological dysfunction. The limitations of current diagnostic options surrounding assessment and prognosti...

Background: The anterior approach to the cervical spine is the most commonly used surgery with effective decompression and less surgical trauma. Anterior plate construct (APC) is considered a standard technique. However, it appears to cause implant failure and postoperative dysphagia. Due to these reasons, locking stand-alone cages (LSCs) without...

Purpose Examine the effectiveness of interventions to approach guideline-adherent surgical referrals for low back pain assessed via systematic review and meta-analysis. Methods Five databases (10 September 2021), Google Scholar, reference lists of relevant systematic reviews were searched and forward and backward citation tracking of included stud...

A Comparison Review of fusion methods (Open Vs Minimal invasive) of sacroiliac dysfunction

Purpose To evaluate intra- and inter-rater agreement and reliability of seven reported disc height index (DHI) measurement methods on standing lateral X-ray of lumbar spine. Methods The adult patients who had standing lateral X-ray of lumbar spine were recruited. Seven methods were used to measure DHI of each lumbar intervertebral disc level, incl...

Routine check-ups for adolescent idiopathic scoliosis are critical to monitor progression and prescribe interventions. AIS is primarily screened via physical examination. If there are features of deformity, radiographs are necessary for diagnosis or follow-up, guiding further management, i.e., bracing for moderate deformity and surgery for severe....

Aims Intraoperative pressure sensors allow surgeons to quantify soft-tissue balance during total knee arthroplasty (TKA). The aim of this study was to determine whether using sensors to achieve soft-tissue balance was more effective than manual balancing in improving outcomes in TKA. Methods A multicentre randomized trial compared the outcomes of...

Purpose Low back pain (LBP), a widely prevalent and costly disease around the world, is mainly caused by intervertebral disc (IVD) degeneration (IDD). Although numerous factors may trigger this degenerative process, microbiome dysbiosis has recently been implicated as one of the likely causes. However, the exact relationship between the microbiome...

Intervertebral disc degeneration (IDD) is the main cause of low back pain, and little is known about its molecular and pathological mechanisms. According to reports, excessive compression is a high-risk factor for IDD; compressive stress can induce oxidative stress in nucleus pulposus (NP) cells during IDD progression that, in turn, promotes cell a...

Intervertebral Disc Degeneration Ancient Chinese astronomers divided the sky into four quarters. Each of the four directions contains seven of the twenty‐eight constellations. The four directions, collectively known as the Four Symbols, each assigned a mysterious animal. They are Azure Dragon on the east, Black Tortoise on the north, White Tiger on...

The blood-spinal cord barrier (BSCB) has been long thought of as a functional equivalent to the blood-brain barrier (BBB), restricting blood flow into the spinal cord. The spinal cord is supported by various disc tissues that provide agility and has different local immune responses compared to the brain. Though physiologically, structural component...

Purpose: To evaluate intra- and inter-rater agreement and reliability of seven reported disc height index (DHI) measurement methods on standing lateral X-ray of lumbar spine. Methods: The adult patients who had standing lateral X-ray of lumbar spine were recruited. Seven methods were used to measure DHI of each lumbar intervertebral disc level. Bla...

Although degeneration of the nucleus pulposus (NP) is a major contributor to intervertebral disc degeneration (IVDD) and low back pain, the underlying molecular complexity and cellular heterogeneity remain poorly understood. Here, a comprehensive single-cell resolution transcript landscape of human NP is reported. Six novel human NP cells (NPCs) po...

Introduction Chronic low back pain disorders (CLBDs) present a substantial societal burden; however, optimal treatment remains debated. To date, pairwise and network meta-analyses have evaluated individual treatment modes, yet a comparison of a wide range of common treatments is required to evaluate their relative effectiveness. Using network meta-...

PurposeTo evaluate the impact of discectomy on disc height (DH) in lumbar disc herniation (LDH) patients following discectomy surgery and address the association of DH change with pain score change.Methods We searched three online databases for randomized controlled trials (RCTs) and observational studies. In LDH patients, eligible for discectomy s...

Aim To assist surgeons to determine a potential approach to reduce incidences of recurrent lumbar disc herniation and assess the current devices regarding their outcomes and complications. Method Four electronic full-text databases were systematically searched through September 2017. All results were pooled utilising meta-analysis with weighted me...

With lower back pain increasingly becoming a highly prevalent economic, clinical and social burden among the global population, the demand for a reliable clinical approach for the quantification of the mechanical properties of the human intervertebral disc (IVD) to detect premature degeneration or identify the underlying pathophysiology that is ess...

Extreme lateral interbody fusion allows for the insertion of a large-footprint interbody cage while maintaining the presence of natural stabilising ligaments and the facets. It is unclear how the load-distribution mechanisms through these structures alters with temporal changes in the bone graft. The aim of this research was to examine the effects...

Introduction Understanding practice-based differences in treatment of lumbar disc herniations (LDHs) is vital for reducing unwarranted variation in the delivery of spine surgical health care. Identifying factors that influence surgeons’ decision-making will offer useful insights for developing the most cost-effective and safest surgical strategy as...

Degeneration of the nucleus pulposus (NP) is a major contributor to intervertebral disc degeneration (IVDD) and low back pain. However, the underlying molecular complexity and cellular heterogeneity remain poorly understood. Here, we first reported a comprehensive single-cell resolution transcriptional landscape of human NP. Six novel human nucleus...

Study design: Translational review encompassing basic science and clinical evidence. Objectives: Multiple components of the lumbar spine interact during its normal and pathological function. Bony stress in the lumbar spine is recognized as a factor in the development of pars interarticularis defect and stress fractures, but its relationship with...

Cigarette smoke (CS) has been consistently demonstrated to be an environmental risk factor for amyotrophic lateral sclerosis (ALS), although the molecular pathogenic mechanisms involved are yet to be elucidated. Here, we propose different mechanisms by which CS exposure can cause sporadic ALS pathogenesis. Oxidative stress and neuroinflammation are...

PurposeRecent animal studies have discovered dysregulation of local inflammatory activity as a novel mechanism to explain fat and connective tissue accumulation in the multifidus muscle in association with intervertebral disc (IVD) degeneration/injury. This study aimed to test whether similar mechanisms are active in humans by investigation of whet...

A previous version of this editorial lacked hyperlink to the articles published for the supplement. The hyperlink to the articles has been enabled and given below. Further, Havey et al. is now updated to Patwardhan and Havey.

Bariatric surgery produces significant and quantifiable reductions in back pain. However, there is a lack of information on the association of weight changes after bariatric surgery with changes in pain score. We aim to evaluate the impact of bariatric surgery on back pain in obese patients and to address the association between changes in body mas...

Degenerative cervical myelopathy (DCM), earlier referred to as cervical spondylotic myelopathy (CSM), is the most common and serious neurological disorder in the elderly population caused by chronic progressive compression or irritation of the spinal cord in the neck. The clinical features of DCM include localised neck pain and functional impairmen...

Study design: Observational study. Objective: To evaluate whether inflammatory and/or muscle regeneration markers in paraspinal tissues (multifidus muscle/fat) during microdiscectomy surgery in patients with lumbar disc herniation (LDH) with radiculopathy, differ between individuals with good or poor outcome. Summary of background data: Struct...

Growth differentiation factor (GDF) family members have been implicated in the development and maintenance of healthy nucleus pulposus (NP) tissue, making them promising therapeutic candidates for treatment of intervertebral disc (IVD) degeneration and associated back pain. GDF6 has been shown to promote discogenic differentiation of mesenchymal st...

Objective: To evaluate if back pain scores in morbidly obese patients change after bariatric surgery. Summary Background Data: Obese patients often complain of low back pain (LBP), however the underlying mechanism is not fully understood. Recent research shows that, next to mechanical loading, the chronic low-grade inflammation that arises in obese...

Objective: The objective of this systematic review was to synthesize the best available evidence relating to the measurement properties of the multidimensional pain assessment tools used to assess postoperative pain in adults. Introduction: Pain is a common and poorly managed occurrence in patients during the postoperative period. Currently, pos...

Introduction It is undetermined whether using sensors for knee balancing in total knee arthroplasty (TKA) improves patient outcomes. The purpose of this study was to compare clinical outcomes of sensor balance (SB) to manual balance (MB) TKA with a minimum two-year follow-up. Methods A consecutive series of 207 MB TKAs was compared to 222 SB TKAs...

Background Multiple components of the lumbar spine interact during the normal and pathological function. Bony stress in the lumbar spine is recognised as a factor in the development of pars defects and stress fractures, but its relationship with intervertebral disc (IVD) degeneration is not well understood. Therefore, a translational review encompa...

Damage to the annulus fibrosus (AF), the outer region of the intervertebral disc (IVD), results in an undesirable condition that may accelerate IVD degeneration causing low back pain. Despite intense research interest, attempts to regenerate the IVD have failed so far and no effective strategy has translated into a successful clinical outcome. Of p...

PurposeThis meta-analysis aims to compare the complication rates of discectomy/microdiscectomy (OD/MD), microendoscopic discectomy (MED), percutaneous endoscopic lumbar discectomy (PELD), percutaneous laser disc decompression (PLDD), and tubular discectomy for symptomatic lumbar disc herniation (LDH) using general classification and modified Clavie...

Previous studies have indicated that growth differentiation factor 6 (GDF6) is a potential candidate for intervertebral disc (IVD) degeneration (IDD) treatment. Here, we investigated the effect of GDF6 on IDD by examining changes in disc structure and the expression of inflammatory and pain‐related factors. A rat posterior disc puncture model of si...

There has been no study to describe the ultrastructural organization of elastic fibers at the interface of the nucleus pulposus and annulus fibrosus of the intervertebral disc (IVD), a region called the transition zone (TZ). A previously developed digestion technique was optimized to eliminate cells and non-elastin ECM components except for the ela...

The increasing prevalence of low back pain has imposed a heavy economic burden on global healthcare systems. Intense research activities have been performed for the regeneration of the Nucleus Pulposus (NP) of the IVD; however, tissue-engineered scaffolds have failed to capture the multi-scale structural hierarchy of the native tissue. The current...

Purpose Animal models are frequently used to elucidate pathomechanism and pathophysiology of various disorders of the human intervertebral disc (IVD) and also to develop therapeutic approaches. Here we report morphological characteristics of the kangaroo lumbar IVDs and compare them with other animal models used in spine research. Methods Twenty-f...

Background The accuracy of surgeon-defined assessment (SDA) of soft tissue balance in total knee arthroplasty (TKA) is poorly understood despite balance being considered a significant determinant of surgical success. The study’s hypothesis was that intra-operative SDA is a poor predictor of coronal balance in TKA.MethodsA prospective, multicenter s...

Purpose: Existing automated spine alignment is based on original X-rays that are not applicable for teleradiology for spinal deformities patients. We aim to provide a novel automated vertebral segmentation method enabling accurate sagittal alignment detection, with no restrictions imposed by image quality or pathology type. Methods: A total of 4...

Real-time health monitoring systems are emerging in diverse medical fields, tracking biological and physiological signals for direct feedback to the user. Orthopaedics is yet to adapt to innovative trends in health monitoring. Despite an evident entry point during orthopaedic surgeries, clinicians remain unable to objectively examine the structural...

Aims: It is unknown whether kinematic alignment (KA) objectively improves knee balance in total knee arthroplasty (TKA), despite this being the biomechanical rationale for its use. This study aimed to determine whether restoring the constitutional alignment using a restrictive KA protocol resulted in better quantitative knee balance than mechanica...

Purpose: The aim of this network meta-analysis (NMA) was to compare the complication rates of discectomy/microdiscectomy, percutaneous laser disc decompression (PLDD), percutaneous endoscopic lumbar discectomy (PELD), microendoscopic discectomy (MED), and tubular discectomy for symptomatic lumbar disc herniation (LDH). Methods: We searched three...

Purpose Abnormal stress in the lumbar vertebra, also known as bony stress, can be a precursor to degenerative changes which may manifest as low back pain (LBP). However, the prevalence of bony stress in the lumbar spine and its relationship with degenerative changes and LBP is unclear. The purpose of this study was to evaluate the prevalence of bon...

Study design A retrospective cross-sectional study. Objective To assess the sensitivity to change and reliability of various mid-sagittal and axial plane metrics in the assessment of patients with single-level degenerative cervical stenosis on T2-weighted MR imaging. Setting A diagnostic MR imaging facility in Sydney (Australia). Methods We retrosp...

Replacing the Nucleus Pulposus for Degenerative Disc Disease and Disc Herniation: Disc Preservation Following Discectomy

A retrospective cross-sectional study. To assess the sensitivity to change and reliability of various mid-sagittal and axial plane metrics in the assessment of patients with single-level degenerative cervical stenosis on T2-weighted MR imaging. A diagnostic MR imaging facility in Sydney (Australia). We retrospectively reviewed T2-weighted MR images...