Surgical Anatomy of Vertebral Artery in Relation to Atlantoaxial Instrumentation: A Cadaveric Study.

BACKGROUND: With the advent of pedicle screws and advanced instrumentation techniques, internal fixation and stabilization of upper cervical vertebrae are possible in fractures of an axis. However, the proximity of vertebral arteries (VAs) poses a unique challenge to surgeons during these procedures and can result in profound physical impairment to patients. Cadaveric studies contributing to fine anatomical details necessitate conducting such studies. METHODS: After receiving due ethical permission, this descriptive cross-sectional study was carried out on 10 cadavers in the department of Anatomy, All India Institute of Medical Science (AIIMS) Rishikesh. Twenty VAs were dissected along their course, and measurements of parameters related to the axis and atlas vertebra were noted. RESULTS: The length of the pre-osseous segment related to the axis (VAX-1) on the right and left sides were from 3.8 to 14.5 mm (7.48±3.88 mm) and 4.46 to 10.5mm (6.94±2.01mm) respectively. The length of the osseous segment related to the axis (VAX-2) on the right side and left sides were from 6.82 to 31 mm (17.9±7.84mm) and 7.35 to 20 mm (15.6±4.53). The osseous segment of the VA related to the axis (VAX-2) shows genu (bend), which extends to a variable distance towards the midline. The mean distance of VA genu from the midline of the axis vertebral body on the right and left sides was 15.6mm and 17.5 mm, respectively. The percentage of superior articular facet (SAF) surface area of the axis occupied by the VA was 25-50% in nine and 50-75% in 11 cadavers, reflecting incomplete occupancy. CONCLUSION: The study suggests that for instrumentation of the axis vertebra in the midline, the minimum distance between the genu of both sides of VA segments, related to an osseous segment of the axis (VAX-2) and medial extent of the VA groove of the atlas, should be considered as a safe zone to minimize inadvertent VA injury. During atlantoaxial fixation through a posterior approach in interarticular, pars, and pedicle screws, the surgical anatomy of the VA in relation to the osseous segment of the VA within the transverse process of the axis should be kept in mind to avoid inadvertent VA injury.

Use of contralateral lateral meniscus for medial meniscal allograft transplantation: a cadaveric study.

PURPOSE: Meniscal allografts are a preferred alternative to menisectomy in cases of irrepairable meniscal tears in young patients. Biological meniscal allograft transplantation requires a cadaveric donor, limiting its availability for transplantation. We are exploring the possibility of using contralateral lateral meniscus for medial meniscal allograft transplantation, as it can be easily procured from proximal tibial cuts from total knee replacement. METHODS: Ten paired knees from five formalin-fixed Indian male cadavers were dissected. Outer and inner circumferences of the medial and meniscus, area of the articular surface of the medial tibial plateau covered by the native medial meniscus and transplanted lateral meniscus were noted. Measurements were taken using software ImageJ (National Institute of Health). The mean of the recordings from two independent observers was taken as the final value. Inter-observer and intra-observer reliability were also calculated. RESULTS: The mean inner circumference of the medial meniscus was significantly larger than the lateral meniscus (p < 0.0001). However, outer circumferences were not significantly different from each other (p = 0.1). Area of the tibial plateau covered by the native medial meniscus was smaller than the area covered by the transplanted lateral meniscus, though the difference was not statistically significant. Inter-observer reliability and intra-observer reliability were good (ICC 0.904 and 0.927, respectively). CONCLUSION: Based on measurements of the outer circumference of medial and lateral menisci, lateral meniscal allograft can be matched for transplantation on the contralateral medial side from the donor with same dimensions of the tibial plateau. Further clinical studies are necessary to prove the clinical significance of this cadaveric study. LEVEL OF EVIDENCE: Diagnostic study.

Management of Mandibular Angle Fractures Using Single Y-Shaped Titanium Miniplate at the Superior Border: A Prospective Clinical Study.

Treatment of angle fractures remains controversial. The various techniques documented for the treatment are: wire osteosynthesis, one miniplate at superior border (2.0 mm), a single plate on inferior border (2.3 or 2.7 mm) along with tension band in the form of arch bar at the upper border, 2 miniplates (1 at superior border and 1 at inferior border), 3-D strut plates or lag screw. To evaluate the efficacy of single Y-shaped titanium miniplate at the superior border in the management of mandibular angle fractures. Total of 15 healthy adult patients reporting to the department of Oral and Maxillofacial Surgery for the treatment of mandibular angle fractures was randomly selected. All the cases were assessed clinically at 1st post-operative day, 1st, 3rd, 6th and 12th week post-operatively for pain, status of occlusion, neurosensory deficit and postoperative hard & soft tissue healing. Radiographic assessment was also done at 1st postoperative day, 6 weeks and 12 weeks. Postoperative pain, infection, wound dehiscence, neurosensory deficit were not evident during the follow- up periods. Radiographically, the fracture reduction was good and plate fracture was not seen in any case. Y- shaped titanium miniplate is an effective method in the management of the mandibular angle fractures and provided satisfactory results.

Anatomy of posterior cruciate ligament retained in a posterior cruciate ligament retaining total knee replacement: a cadaveric study.

BACKGROUND: Recent evidence has highlighted a risk that the majority of posterior cruciate ligament (PCL) is removed while making bone cuts in tibia and femur during total knee replacement surgery. Aim of this cadaveric study is to calculate how much PCL footprint is retained in a PCL retaining prosthesis after routine tibial and femoral cuts are made.  Methods: Twelve paired formalin-fixed Indian cadaveric knees were studied. Knees were disarticulated and all soft tissues were circumferentially removed from the tibia and femur. Footprints of antero-lateral and postero-medial bundles were marked on tibia and femur. Proximal tibial and distal femoral cuts were made using standard cutting jigs (Zimmer NexGen LPS). Digital photographs were taken with a magnification marker attached on the bone before and after making the cuts. Area of PCL insertion before and after the bone cuts was measured using software ImageJ (National Institute of Health). RESULTS: Footprint on tibial side was reduced by 9.1%, and on femoral side by 21.8%. Footprint of AL bundle was reduced by 24.3% on the tibial side and by 15.3% on the femoral side. Footprint of PM bundle on tibia was not affected by the bone cut but was reduced by 18.5% on the femoral side. CONCLUSION: Tibial and femoral insertions of PCL are relatively well preserved after bone cuts are made in a posterior cruciate retaining TKR. There is differential sectioning of antero-lateral and postero-medial bundles of PCL on tibial and femoral sides.

What is wrong with the MCI?

In the wake of the Medical Council of India's (MCI) take on the promotion of faculty recently, it is clear that the faculty of medical institutions across the country are in a state of alarm. A situation in which the whole onus of research is put on the faculty is quite quirky when there is no consideration of the fact that most medical colleges in India do not have a system of intramural funding, apt infrastructure and a pertinent environment for carrying out good research.

Classification and fascicular analysis of variant branching pattern of femoral nerve for microsurgical intervention: a series of thirteen cadavers / Clasificación y análisis fascicular de las variantes en el patrón de ramificación del nervio femoral en intervenciones microquirúrgicas: una serie de 13 cadáveres

Femoral neuropathy associated with lower limb is treated by surgical intervention through activation/regeneration/grafting of nerve fibers by a nerve cuff electrode implant or neuro-prosthesis. These procedures require detailed and precise knowledge of neuro-anatomical variants of the femoral nerve and its fascicular anatomy so that the nerve injury can be investigated and treated more efficiently. The aim of the study is to uncover the variations both in the femoral nerve and its branches, to classify them and to bring out corresponding fascicular anatomy using a hypothesis based on the principle of consistency, continuity and traceability of fascicles. The study was carried out in the Department of Anatomy AIIMS Rishikesh using 13 matched lower limbs (26 femoral nerves) from 13 cadavers. The femoral nerve was exposed in the femoral triangle and traced to the posterior abdominal wall. Variations in the shape, size and course of the femoral nerve and its branches were analyzed. The fascicular arrangement was also conceptualized based on the hypothesis. Seven classes, high division, trunk anomaly, semi-scattered, scattered branching pattern, pectocutaneous, lateral cutaneous nerve of thigh and nerve to sartorius anomalies were detected. The corresponding fascicular organizations were modeled. The seven classes along with corresponding fascicular pattern will be very useful for neurosurgeons, radiologists, anesthetists and anatomists in diagnosis and treatment of femoral neuropathy.

La neuropatía femoral asociada con el miembro inferior es tratada por intervención quirúrgica a través de activación, regeneración e injerto de fibras nerviosas mediante un implante de electrodo de manguito de nervios o neuro-prótesis. Estos procedimientos requieren un conocimiento detallado y preciso de las variantes neuro-anatómicas del nervio femoral y su anatomía fascicular de modo que la lesión del nervio pueda ser investigada y tratada de manera más eficiente. El objetivo del estudio fue descubrir las variaciones tanto en el nervio femoral y sus ramas y clasificarlos a partir de la anatomía fascicular utilizando una hipótesis basada en el principio de la continuidad y trazabilidad de los fascículos correspondientes. El estudio se llevó a cabo en el Departamento de Anatomía AIIMS Rishikesh utilizando 13 miembros inferiores pareados (26 nervios femorales) de 13 cadáveres. El nervio femoral se expuso en el triángulo femoral y fue trazado en la pared abdominal posterior. Se analizaron las variaciones en la forma, tamaño y trayecto del nervio femoral y sus ramas. El patrón fascicular fue conceptulizado de acuerdo a la hipótesis planteada. Se detectaron anomalías clasificadas en: siete clases, división alta, anomalías de tronco, semi-dispersos, patrón de ramificación dispersa, pectocutáneo, nervio cutáneo lateral y nervio del músculo sartorio. Las clasificaciones junto con el patrón fascicular correspondientes serán de gran utilidad para los neurocirujanos, radiólogos, anestesistas y anatomistas en el diagnóstico y tratamiento de la neuropatía femoral.

Morphometric Analysis of Axis and Its Clinical Significance -An Anatomical Study of Indian Human Axis Vertebrae.

BACKGROUND: The atlas and axis vertebra have unique shape and complex relationship with vertebral artery. Fracture of dens of axis accounts for 7-27% of all cervical spine fractures, but surgeries in these regions are highly risky because of the reported incidences of vertebral artery injury. AIM AND OBJECTIVES: The study was designed to measure morphometric data of human axis vertebra, of Indian origin. The different anatomical parameters on dry specimen of human axis vertebrae were established and the results were compared with other studies. MATERIALS AND METHODS: Thirty intact human axis vertebrae were measured with digital vernier caliper and mini-inclinometer. Various linear and angular parameters of axis were observed. RESULTS: The mean distance from the midline of body to the tip of transverse process of axis was 29.32 mm on right side and 29.06mm on left side. The mean distance from the midline of body to the lateral most edge of superior articulating facet was 22.8 mm on right side and 22.6 mm on left side. The mean value of anterior and posterior height of axis was 34.33±2.69mm and 30.56±2.78mm respectively. The anterior and posterior height of body of axis was 19.67 mm and 16.67mm respectively. Mean A-P and transverse diameter of inferior surface of axis was 15.42mm and 17.7mm respectively. Mean transverse diameter and mean A-P diameter of odontoid process was 9.32 mm and 10.1 mm respectively. Mean anterior and posterior height of the odontoid process was 14.66 mm and 13.89mm respectively. Mean of dens axis sagittal angle (angle between an axis that was imagined to pass longitudinally through the dens axis and the vertical line on a sagittal plane) was 13.23 degree. The shape of superior articulating facets of C2 varies from oval to circular. In the present study, 84% of SAF were oval and 16% were circular. Inferior articulating facets were circular in shape in 90% cases, and oval in 10% vertebra. Mean pedicle width was 10.07mm on right side and 10.52mm on left side. Mean transverse diameter of vertebral canal was 22.37±1.73mm. Mean of A-P diameter of vertebral canal at inlet was 18.31±2.05mm and mean of A-P diameter of vertebral canal at outlet was 14.84±1.63mm. CONCLUSION: These results obtained from this study may be helpful for the surgeons in avoiding and minimizing complications such as vertebral artery injury, cranial nerve damage and injury to other vital structures while doing surgery around cranio-vertebral region.