Browsing by Author "Prithishkumar, Ivan James"

Now showing 1 - 9 of 9

Determining anatomically-safe corridors for placement of lateral mass screws in the first cervical vertebra of the Emirati population – a CT study
(Springer Science and Business Media LLC, 2025-01-15) Suresh, Dineshwary; Naidoo, Nerissa; AlSharhan, Rashid; Lakshmanan, Jeyaseelan; Prithishkumar, Ivan James
The first cervical vertebra (C1) is atypical in shape and bears a complex relationship with important neurovascular structures such as the vertebral artery and cervical spinal cord which are at risk of injury during misplaced screw fixation of C1. Placement of screws into the lateral mass of C1 vertebra is performed for stabilization of the craniovertebral junction. The objective of this study was to describe ideal screw dimensions, precise entry points, safe bony corridors, and ideal trajectories for placement of lateral mass screws in the Emirati population. CT scans of 160 Emirati patients (> 18 years) were studied and variables relevant to lateral mass screw fixation were measured. Screw entry at the centre of lateral mass, below its junction with the posterior arch, allowed straight screws of lengths of 20 mm and 19.5 mm in Emirati males and females, respectively. A medial angulation of 20° in males and 15° in females allowed maximum bone purchase. Screw entry at the junction of medial margin of posterior arch and lateral mass allowed straight screws of length 18 mm in both males and females. We recommend safe cephalic angulations of 19° and 16°in males and females, respectively. The mean critical width was 7.6 mm in males and 6.8 mm in females which would safely permit screws of width 4.0 mm. Pre-operative knowledge of the above dimensions would help in greater precision, minimizing the risk of injury to neurovascular structures in the vicinity of C1 lateral mass.
Double burden of malnutrition among women of reproductive age: Trends and determinants over the last 15 years in India
(2024) Prithishkumar, Ivan James; Lakshmanan, Jeyaseelan
Abstract Introduction: Double burden of malnutrition (DBM) has been recognized by the World Health Organisation (WHO) as an emerging Global Syndemic characterized by the simultaneous occurrence of both undernutrition and overnutrition. Women of the reproductive age group (15 to 49 years) are disproportionately affected by DBM and are at high risk of continuing the intergenerational cycle of malnutrition. This study aims to assess the changing trends and determinants of DBM among women of the reproductive age group in India. Materials and methods: We used data from three rounds of National Family Health Surveys (NFHS-3,4,5) conducted in years 2005–06, 2015–16, and 2019–2021. Descriptive statistics and Poisson regression analysis were done using weights with log link function. Results: The prevalence of anaemia, underweight and overweight/obesity was 57.2%, 18.6% and 24%respectively. The combined burden of underweight and anaemia has declined by 46% (21.6% to 11.7%), whereas the combined burden of overweight/obesity and anaemia has increased by 130% (5.4% to12.4%) in the past 15 years. The prevalence of DBM, which includes both underweight and overweight/obesity with anaemia was 24.1% in 2021, a decline of 11% in 15 years. Women who were younger, rural, less educated, poor and middle class, and women living in the eastern, western and southern regions of India had higher risk for being underweight with anaemia and lower risk for developing overweight/obesity with anaemia. Conclusion: Thesignificant decrease in underweight yet enormous increase in overweight/obesity over the past 15 years with the persistence of anaemia in both ends of the nutritional spectrum is characteristic of the new nutritional reality emphasizing the need to address malnutrition in all its forms. It is critical to consider geography and a population specific, double-duty targeted intervention to holistically address the risk factors associated with DBM and accomplish India’s commitment to the global agenda of Sustainable Development Goals-2030.
Estimating aspect ratio of the distal femur and proximal tibia in the Emirati population from MRI scans of the knee: a preliminary experience
(2023) Prithishkumar, Ivan James
Abstract: Size and shape of knee implants play an important role in the success of total knee arthroplasty. Several studies have identified anthropometric differences of the distal femur and proximal tibia between the genders and ethnicities. Ill-fitting prosthesis can cause overhang or under-ft resulting in persistence of pain, periprosthetic fracture and decreased range of motion. The purpose of this study was to estimate the aspect ratio of distal femur and proximal tibia in the Emirati population and determine whether gender differences exist within this group. Magnetic resonance imaging datasets of unilateral knees scans performed on adult Emirati patients at a tertiary care hospital were retrospectively examined. Knee parameters were obtained from 65 males and 46 females (n= 111). Females showed significantly smaller AP and ML dimensions of distal femur and lower aspect ratios compared to males (p< 0.001). Proximal tibial dimensions (AP and ML) of Emirati women are also significantly smaller compared to men. However, aspect ratio of proximal tibia did not show gender variation (p= 0.956) within the Emirati population. Emirati knees showed significant gender differences in bony dimensions and aspect ratio of the knee, and also have smaller aspect ratios when compared with most other population groups.
Estimation of Anatomical Dimensions of the Thorax from Computed Tomography Images of the Adult ‎and Pediatric Indian Population for Developing Optimal Radiological Protocols
(2021) Nathan, Vandana; Prithishkumar, Ivan James
Purpose:‎ Ionizing radiation has been extensively used for medical diagnosis since its discovery in 1895; however, ‎excessive use can lead to deleterious effects. Prior knowledge on radiological protocols based on ‎simulations would be a practical tool for optimal use of radiation.‎ Materials and Methods: Scan length of the thorax was measured from computed tomography (CT) topographic images and ‎cross‑sections at three levels of the thorax were measured from tomographic images of 500 adults and ‎‎340 children who had undergone CT thorax examinations using Centricity workstation software. The ‎effective diameter (ED) of the thorax was calculated from anterio‑posterior (AP) and transverse ‎anatomical dimensions. Results: A 17% increase in scan length was observed for 6–10 years age group ‎compared to 0–5 years, whereas there was marginal increase for 11–15 years of age. A 11.5% increase ‎was observed for 16–18 years compared to 11‑15 years age group. The cross‑sectional phantom ‎dimensions were calculated from ED measurements obtained from three regions of the thorax. ‎ Conclusions: This study has provided age‑ and gender‑specific reference scan lengths, AP and transverse ‎dimensions and ED for radiological examinations of the thorax. This information is useful to develop ‎age‑ and gender‑specific preset protocols and fabricate phantoms of the thorax for the pediatric and ‎adult Indian population.‎
Feasibility of transpedicular screw placement through the posterior arch of C1: A CT study in the Emirati population
(Elsevier BV, 2025-06) Prithishkumar, Ivan James; Suresh, Dineshwary; Naidoo, Nerissa; AlSharhan, Rashid; Lakshmanan, Jeyaseelan
Background: Instrumentation of the lateral mass of first cervical vertebra (C1) is required in atlantoaxial instability. C1 bears a complicated relationship with adjacent neurovascular structures such as the vertebral artery and cervical spinal cord, which are at risk of injury in a misplaced screw. The objective of this study was to look at the feasibility of transpedicular screw placement into the C1 lateral mass with entry through the posterior arch. Methods: Computed tomography images of the cervical spine in 160 adults (>18 years) who are natives of the United Arab Emirates (UAE) (M = 80; F = 80) were reviewed. Morphometric parameters relevant to pedicle screw fixation via the posterior arch were studied. Results: Mean intraosseous distance from screw entry point in the posterior arch to the anterior cortex of lateral mass following a straight course without any inclination was 28.0 mm in males and 29.0 mm in females, allowing a safe distance of 3.2 mm from the foramen transversarium laterally and 9.0 mm from the vertebral canal medially. A medial inclination of 18◦ in males and 14◦ in females allows for increased bone purchase. Mean height of the pedicle at its junction with lateral mass was 5.6 mm in both sexes. However, the mean height of the posterior arch at the vertebral artery groove was 3.3 ± 0.4 mm in males and 3.1 ± 0.4 mm in females. Conclusion: We recommend placement of 3.5/4.0 mm screws using the notching technique, of length 28–30 mm with a slight medial angulation of 15◦ for increased bone purchase and greater stability of fixation.
Integrating virtual reality to enhance remote teaching of anatomy during unprecedented times
(Korean Association of Anatomists, 2024-12-03) Boillat, Thomas; Prithishkumar, Ivan James; Suresh, Dineshwary; Naidoo, Nerissa
The COVID-19 pandemic necessitated a global paradigm shift in the teaching of human anatomy. Most institutions successfully transitioned from traditional in-person teaching methods, to various distance-learning strategies. Since virtual reality (VR) offers immersive three-dimensional (3D) experiences, this study investigated students’ experiences regarding the capacity of VR to support distance-learning of anatomy. Using the VR application, 3D Organon Virtual Reality Anatomy, anatomy instructors pre-recorded learning content as 360-degree videos with live voice-over and integrated it into the teaching material of the MBBS first-year abdomen, pelvis, and perineum-structure and function course. A 19-item 5-point Likert scale questionnaire, comprising of two major categories, “VR experience in anatomy lessons” and “VR in anatomy lessons vs. traditional cadaveric dissection” was disseminated. Post-evaluation analysis revealed a response rate of 63.5%. Almost 70% of students agreed that VR was instrumental in solidifying their theoretical understanding and improved spatial awareness with better retention of anatomical relationships. Approximately 50% wanted to continue using VR even if instruction becomes onsite. Though 72% of participants agree that VR addressed the session learning objectives only 24% agree that it is similar or better than cadaveric dissection, thus preferring cadaveric dissection to VR. Only 12.1% agree that VR is more beneficial to cadaveric dissection. Our exploration into the integration of VR technology in anatomy teaching has revealed promising opportunities. While VR can augment traditional teaching methods in unprecedented times such as war, floods or global pandemic, it should not replace hands-on cadaveric learning entirely, but rather complement existing approaches.
Localizing motor entry points of adductor muscles of thigh for motor point procedures in the treatment of adductor spasticity
(2024-08) Lakshmanan, Jeyaseelan; Prithishkumar, Ivan James
Abstract Spasticity which is focal or segmental such as affecting a single muscle group or limb can be treated by chemical neurolysis or surgical denervation at the neurovascular hilus. This study determines the motor entry points (MEPs) of adductor muscles of the thigh in the adult Indian population and identifies precise anatomical landmarks for the successful performance motor point procedures for the relief of muscle spasticity. A total of 10 adult lower limbs were dissected, and nerve branches to adductor muscles were carefully exposed up to their MEP. The morphometry of adductor muscles, precise locations of proximal and distal MEPs, and ideal sites for motor point procedures were identified. The median number of MEPs in adductor longus was two. Most of them were located between 40% and 50% of the muscle length i.e., in the third-fifth of the total muscle length. Adductor magnus and gracilis had a median number of one and six MEPs respectively. The ideal site of motor point procedures is in the second-fifth of the muscle length for both. This preliminary study describes the location of MEPs and ideal sites of motor point procedures in the adductor muscle of the thigh. However, further cadaveric and electromyographic studies with larger samples are necessary to investigate precise locations of MEPs aiding in the treatment of spasticity.
A novel reconstructive approach of the lumbar vertebral column from 2D MRI to 3D models
(2022-11) Naidoo, Nerissa; Lakshmanan, Jeyaseelan; Prithishkumar, Ivan James
Introduction: Low back pain (LBP), arising from the lumbar vertebral column (LVC), is a global burden, ranking highest in terms of disability. In the United Arab Emirates (UAE), there is a high prevalence of LBP in the adult population. As MRI has emerged as the mainstay in assessment of LVC-related conditions, this study aimed to reconstruct reproducible 3D LVC MRI models from 2D MRI scans. Methods: Following the extraction of serial 2D MRI scan slices from an existing image database, ffty 3D MRI models (n = 50) were retrospectively reconstructed (Mimics Innovation Suite ®) and analyzed through the bootstrapping technique. Results: Lumbar vertebral bodies depicted kidney and oval shapes, with an increasing frequency of the former traced from L1 to L5. Traction (10%) and claw (14%) osteophyte types were noted. The inferior rims of L2 (2%) and L4 (4%) presented with the co-existence of both osteophyte types, which was reflective of the same degenerative process. Morphometric dimensions of L1 were also determined: Anterior vertebral height: 29.6 ± 3.5 mm (28.6–30.5 mm); Posterior vertebral height: 26.8 ± 3.1 mm (25.9–29.6 mm); Superior vertebral width: 40.6 ± 3.8 mm (39.6–41.6 mm); Intervertebral disc height between L1 and L2: 15.9 ± 6.3 mm (14.3–17.7 mm). Conclusion: A proof-of-concept in the reconstructive approach of the LVC was established, which introduces a process through which a normative simulated dataset can be obtained in the extended population. Additionally, these values will assist to detect structural disproportions and changes and contribute to pre-operative planning and artificial intervertebral disc implant design.
Prevalence of the additional head of quadriceps femoris in the South Indian population: a cadaveric and radiological study
(2021) Prithishkumar, Ivan James
Abstract: Quadriceps femoris is an extensor muscle in the anterior compartment of thigh and is traditionally taught to be composed of four heads. Recently, there is an increased interest in the occurrence of an additional muscle head of quadriceps femoris. But scientifc knowledge regarding its incidence is lacking in the South Indian population. This study was done to confrm the presence of the additional head by routine anatomic dissection and radiological imaging techniques. Forty-one formalin fxed human cadaveric lower limbs were dissected and the morphology of the additional head was noted. Retrospective analysis of 88 MRI images of patients was done. The additional muscle head was present in 43.9% of the cadaveric lower limbs and was consistently located between the vastus lateralis and vastus intermedius. It originated from variable portions of the greater trochanter, intertrochanteric line, lateral lip of linea aspera and lateral surface of the shaft of femur and inserted either as a muscle belly or as an aponeurosis into the vastus intermedius (55.6%), vastus lateralis (22.2%) or directly into the base of the patella. It received its vascular supply from branches of the lateral circumfex femoral artery and was innervated by branches from the posterior division of the femoral nerve. In addition, the additional muscle head was identifed by MRI and its incidence was reported to be 30.68% for the frst time in living subjects. The result of this study provides additional information in understanding the morphology of the quadriceps femoris muscle.