The surgery on the spine is still in many parts of the world, a matter of controversy, with both the public and the medical community associating it with a poor outcome. Most surgical approaches were limited to posterior laminectomy for a wide range of conditions. However, with technological advancement and availability of better modalities of radio-diagnosis, better knowledge of the biomechanics of the spine and the use of Microsurgery, spinal surgery has now become a very sophisticated specialty offering excellent results. New approaches have been devised and with the use of microsurgical techniques, many spinal pathologies are now being dealt with safety and with minimal morbidity.
Some of the conditions that are being routinely dealt with are disc pathologies, spondylosis and Spondylolisthesis, OPLL, Caries spine, Fracture spine, spinal tumours, etc., With advent of better techniques and the availability of good implants for spinal stabilization, it is possible to mobilize the patient early. For example, now all cervical disc pathologies are approached anteriorly with less tissue handling and bleeding with shortened hospital stay. For lumbar disc pathologies, laminectomy has given way to microsurgical fenestration, which does not involve removal of bone. Following surgery patients are mobilized the same day and are discharged on the second or third day. Artificial discs and spacers have been introduced recently in an attempt to restore the natural anatomy following disc excision. Anterior pathologies involving the vertebral bodies are now being routinely dealt with by corpectomy which is done by the anterior cervical, transclavicular, or trans -thoracic or retroperitoneal approaches depending on the level of involvement. The experience gained over the years in these surgeries and the knowledge and use of different implant systems has allowed surgeons to undertake surgery of complex spinal problems with reasonably good results.
Surgery on the spine is performed to decompress the spinal cord and or nerve roots, and to reconstruct the spinal column which has been disrupted either due to pathology or because of surgery. Experience with spinal microsurgery has enabled us to approach lesions with minimal disruption of the spinal column. We now know that the stability of the spine is not dependent solely on the integrity of the spinal column but also on the functional capabilities of the paraspinal muscles and the ligaments of the spine, which participate in the “Flag pole” concept of spinal stability. This, along with experience with implant systems has encouraged more difficult reconstructions. These two factors have allowed us to undertake the management of certain complex pathologies, from which we have gained furthur knowledge and experience. We would like to share these experiences with you. The problems faced in these special complex cases are in the diagnosis and approach to the lesions, as well as in the reconstruction of the spine.
Case no I A 36 year old male presented with persistent neck pain following a road traffic accident. A month later he started developing stiffness of all 4 limbs. The x-ray of the cervical spine was reported as normal. The MRI scan showed a C7-T1 total dislocation with pressure on the cord from both anterior and posterior. (Fig 1).
He was operated in a single stage anesthesia. Under skull traction, a posterior approach was first utilized to release the facets at C7-T1. The posterior elements of T1 were found to be floating and these were removed. The patient was then turned supine and through a classical anterior cervical approach and a trans-clavicular trans-sternal extention, corpectomy of T1 was done along with discectomy of the adjacent levels. The gap was bridged by a tricorticate bone graft, and stabilization was performed using an anterior monocortical locking cervical plating system. The patient was once again turned prone and a posterior fusion and stabilization was done using Hartshill rectangle and wires. Thus the spinal cord was decompressed and a 3600 stabilisation was done . (Fig 2).
The patient was mobilized on the 8th postoperative day and was discharged without any fresh deficits. The patient is asymptomatic at one year follow up and the radiology is showing good fusion and proper implant position.
Cervico-thoracic dislocations are notorious for being missed as the region is poorly visualized on plain lateral radiographs. Persistent pain or the development of neurological deficit is often the only indicator of a pathology, unless carefully looked for in the AP radiograph. The MR scans will clearly delineate these dislocations which may be complete with spondyloptosis. These patients require careful handling, as the region is difficult to immobilize even with skull traction. In most instances reduction does not take place and it is necessary to decompress the cord and stabilise the spine from both anterior and posterior.
Case 2 : (Fig 3,4) A 5 year old girl presented with a spinal deformity and spastic paraparesis of recent onset. The deformity was extensive and there was a dysraphic state of the entire lumbar spine. The posterior elements were absent from L1 to S1, and the lateral ends of the rudimentary pedicles were both visualized and palpable through the skin due to the gross kyphosis. The radiology revealed the extent of the deformity and the associated abnormalities. The conus was stretched over the hump of the internal gibbus at L1-L2. The management problems of this child are discussed in the presentation including the problems of instrumentation in children.
Case 3: A 45 year old man underwent lithotripsy under spinal anesthesia. He complained of persistent back pain following the procedure. An x-ray was taken and was reported normal and he was put on analgesics and bed rest. As he did not find relief and as pain worsened, the x-rays were repeated and an MR was done. These showed signal changes in the vertebral bodies and disc spaces indicative of infective discitis and spondylitis. There was also evidence of root pressure at multiple levels. He was operated upon to no avail. He presented to us at this stage with severe pain and radiology showing active infective spondylitis, with gross deformity.(Fig 5) The issues in management were the role of surgery in the management of the patient, whether or not instrumentation was indicated, what should be done for the gross deformity. We performed a relaminectomy and removed all seen infected material from the spinal canal, releasing the nerve roots and clearing all sequestra and debris. The patient was placed on complete bed rest and antibiotics. He gradually improved and the infection disappeared with healing of the bone. He has since been mobilized and is doing well.
Intraparenchymal lesions may present in the following ways with respect to the brain surface:
The advantage of the operating microscope goes beyond the basic gains of illumunation and magnification, allowing precise dissection. The greatest advantage of the microscope is in the capability of sharp stereoscopic focus in a narrow deep opening with adequate illumination. The microscope creates a telescope effect which allows the surgeon to work at a depth of 10- 12cm through a small opening 5 mm wide and 16 mm long. The ability to work in this narrow and deep field with depth perception and illumination is indispensable. This allows the surgeon to minimise both the opening made in the normal brain tissue and also the use of retractors during surgery. Retractors cause brain injury in two distinct ways. With increasing retractor pressure the brain tissue gets pulled apart displacing and destroying fibre tracts. Increasing retractor pressures can cause venous hemorrhage in the adjacent brain tissue due to impedance to venous flow. Microsurgical techniques used in the removal of intraparenchymal lesions involve staying within the confines of the lesion, prograssive debulking and removal of the tumour inside out. Once the main bulk of the tumour is excised, space is created for finer dissection and removal of the margins of the tumour without furthur retraction.
Thus with the microscope the surgeon does not have to make space (by retraction) to remove a tumour. The surgeon makes use of the space that the tumour has occupied and is therefore able to remove tumours with minimal or no retraction.
In the early 1900s surgeons like Cushing, Dandy and Krause demonstrated surgical approaches to deep seated brain tumours and redefined neurosurgical principles. The surgeons removed brain tumours and other lesions, with a morbidity and mortality rate that was acceptable at that period of time, taking into consideration the lack of imaging, monitoring, anesthetic and surgical technology. The advent of new imaging technology in the last 20 years, has made possible precise tumour localisation, and characterisation.. This, along with improved monitoring and anaesthesia, has put the onus back on the surgeon to find the means to tackle these lesions which are now so clearly seen and defined.
Intracerebral tumours present to the clinician due to either raised intracranial pressure, or the local effect of the lesion on the brain as seen by seizures or neurological deficit. The main aim of surgery for these lesions is radical excision, while procuring a histological diagnosis. Radical excision in turn benefits the patient by effecting a reduction in the intracranial pressure, and reducing the effects of the lesion on the surrounding brain. It is the duty of the surgeon to ensure that in doing so, the patient improves, or at the least, maintains his or her neurological condition. The goals in front of the surgeon are therefore radical excision of the tumour with a good neurological result. The use of microsurgical techniques at surgery greatly help the surgeon in achieving these goals and it is mandatory that surgeons use the microscope at all surgeries.
Experience with microsurgical techniques has brought in the knowledge that the anatomy of the brain is such that it allows access to deep structures. “The brain is not an isolated compact structure like an island unto itself; rather it is like a continent with a multifaceted coastline with many water inlets; it floats in a sea of CSF , with rivers of cerebrospinal fluid which allows access to its interior”. (M G Yasargil Clin.Neurosurg 1986) Knowledge of this sulcal, fissural and cisternal anatomy is essential for the proper surgical management of brain tumours. While every neurosurgeon is well versed with the gyral anatomy and the partition of the brain into supra and infratentorial compartments, the sulci, fissures and cisterns have generally been excluded from the surgeon’s perspective.
The main reasons for morbidity following surgery on intraparenchymal lesions include:
The route of approach to the lesion should be chosen such that the trauma caused to the normal brain is minimal. When the entire tumour is surfacing the lesion is removed by going through the surfacing area without disturbing the surrounding normal cortex. When only a small portion of the lesion is surfacing, the surgeon must stay within the surfacing small area of the tumour and debulk the lesion so that the lesion becomes small enough to be removed through the small cortical opening. However when the lesion is not surfacing the surgeon must study the available radiology to decide on the shortest path through normal white matter. The approach then depends on where the lesion is with respect to the gyral and sulcal pattern of the brain. If the tumour is not surfacing but just beneath the surface on the crest of the gyrus, the best approach would be to go through the top of the gyrus. If however the lesion is furthur deep and is close to one of the banks of the sulcus, the surgeon would have to approach the lesion through the sulcus. Similarly, the trans-sulcal approach has to be used when the lesion is deeper or intra-ventricular. Similarly approaches through fissures and cisterns can take the surgeon to deep portions of the brain hitherto thought to be inaccessible.
The mainstay of the transsulcal approach is to use the shortest route between the surcase of the brain and the tumour so that surgical trauma to the normal brain is minimised. While approaching the tumour the microsurgeon is also saddled with the responsibility of looking after the microvasculature of the normal cortex and maintenance of the arachnoidal vessels and layer, so that the normal CSF milieu of the surrounding brain is maintained.
The vessels that lie in relation to a tumour require careful consideration from the surgeon. Venous channels require more respect than the arteries. It is of prime importance that no normal venous channel be obliterated during surgery. While it is expected that with the reduction of intracranial pressure after tumour removal, collateral venous channels open up, and therefore obliteration of one or two veins do not affect venous outflow, this may not always be the case. Venous infarcts will develop where crucial channels have been sacrificed. The surgeon should therefore ensure that no venous channel is sacrificed unless there is no other option left.
There are three types of arteries that may be seen in relation to a tumour: normal arteries, transit arteries and feeder arteries. Normal arteries may lie close to the tumour margin especially when the tumour abuts a sulcal surface. The surgeon must be able to identify the normal arteries and preserve them. Transit arteries pass through the tumour or on the surface of the tumour and go on to feed normal areas distal to the lesion. During their passage they may send off branches to feed the tumour. Generally vessels greater that 1mm do not act as terminal branches for a tumours. It is therefore essential that the surgeon carefully isolate and identify the transit vessel, and coagulate only the feeding branches while preserving the former main vessels. Preserving the normal vessels and resecting only the feeders maintains normal blood supply to the adjacent normal brain while depriving the tumour of its vascular input.
At the time of tumour removal it may occasionally be difficult to decide which is a transit vessel and which is a terminal feeder. Debulking the tumour and creating space around the margins will bring into view the anatomy of the vessel and help dissect transit vessels and identify the feeders.
12 year old boy presented with symptoms and signs of raised intracranial pressure and right hemiparesis. The CT scan (Fig 1) showed a mixed density irregularly enhancing lesion situated in the left medial temporal region bordering unto the ambient cistern medially and the region of the carotid bifurcation anteriorly. The lesion was approached through the inferior temporal sulcus (Fig 2) and was removed radically expect for where the tumour was surrounding the branches of the Carotid, Middle Cerebral and Anterior cerebral arteries.(Fig 3,4).
Microsurgical techniques have to be employed to achieve the goal of a good neurological result with radical tumour excision. The use of the operating microscope cannot be restricted to the occasional difficult case. It must be made order of the day as very case must be given its due and every patient the best there is to offer. To give the advantage of precise dissection and preservation of function to benign tumours and to believe that it is not essential for malignant lesions of the brain is criminal. Only when the surgeons uses the microscope in all cases and at all times will the surgeon be able to confidently tackle the most difficult of situations. One cannot just climb onto the stage and perform. Practice makes prefect -- Use the surfacing and easier tumours to practice microsurgical techniques -- so that when the need arises in the case of deep seated lesions one is able to rise to the occasion.
The Operating Microscope does not only magnify the operative field but also the errors of the surgeon.The implication --- the surgeon is forced to reduce the errors made. The result --- A mediocre surgeon becomes a good surgeon ! A good surgeon becomes an excellent surgeon !!
Is Microsurgery required in every case? The answer:Yes , of course!
Ossification of the posterior longitudinal ligament (OPLL) as a cause of cord compression was first reported by Key in 1838 (1), and by Tsukimoto in Japan in 1960 (2). It was long thought to be a disease of the Japanese (in whom the incidence is 2.2 % in asymptomatic patients and 27 % in the presence of myelopathy). Improved imaging modalities and recognition of the disease have shown a 20 to 23 % incidence the Caucasian races in the presence of myelopathy (3,4). Recent reports have shown that non-Japanese Asians too may have an incidence close to that of the Japanese. However, there are no proper epidemiological studies to prove or refute this statement.
Clinically the patients present with symptoms of radiculomyelopathy, similar to those of spondylosis. One distinguishing feature, found in the author’s series was the singular absence of brachial neuralgia as a primary symptom. The latter was observed only in patients in whom a disc prolapse was the compressive element. Trauma aggravates symptoms in a patient with cervical OPLL. Relatively minor injuries can also precipitate severe symptoms and signs in an otherwise asymptomatic patient.
Plain lateral radiographs of the cervical spine show OPLL as a dense band posterior to and extending across vertebral bodies. However, we found a false negative rate of In their prospective study of the cervical spine of 240 patients, Jayakumar et al (10) found evidence of OPLL in only 13 or 4.8%. The cause of the poor x-ray visibility of OPLL in patients of South Asia is not known. A similar low incidence of intracranial calcification, normal and pathological, has been reported in Indian patients and has been thought to be related to the type of nutri¬tion (26). This could account for the low incidence of OPLL reported from this part of the world. While plain x-rays and tomograms can be used to screen patients for OPLL, MRI and CT scans are essential to study the ossification.
Classification systems have been devised depending on the configuration of the OPLL on radiographs and sagittal MR scans. The most common system used is that which divides the OPLL into Continuous, Segmental, Mixed and Circumscribed types. Using axial CT scans OPLL has been classified into different types depending on shape (17). These systems do not help in the planning of surgery. A more useful system is where the OPLL is divided into “Localised” and “Extensive” types on the sagittal plane. The axial sections of the MR and / or CT scans may be used to study whether the OPLL is central and symmetrical , or, eccentric and asymmetrical in its configuration. These will influence decisions regarding approach and the technique of excision of the OPLL.
Surgical options for cervical OPLL include anterior and posterior decompres¬sive procedures. Which of these gives better results is still controversial (3,7,21,22). While anterior decompression and excision of the OPLL is preferred as it directly deals with the compressive pathology, a posterior decompressive procedure remains a popular choice when the cord is compressed for more than three vertebral segments . Baba et al (21) reporting on 85 patients who had undergone anterior decompression and fusion for cervical myeloradiculopathy due to OPLL found the anterior approach satisfactory only when done in upto two vertebral levels. For more extensive involvement they recommend posterior decompressive surgery. This is in contrast to the conclusions drawn by Epstein (3,22), who prefers the anterior approach . In her opinion, those patients who were in the worst pre-operative grade and underwent a corpectomy and fusion had the best recovery, while those who underwent a posterior procedure had the worst outcomes. We have found both anterior and posterior procedures to give good outcomes on followup. However, patients who undergo anterior procedures experience improvement early in the post-operative period , unlike patients who undergo posterior procedures. We recommend anterior approaches when the compressive element is three vertebral levels or less; and posterior procedures when the compressive element extends over three or more vertebral segments, or behind the body of the axis.
The choice of surgical procedure is dependant on the patient’s clinical picture and the radiological findings. MR scans are the most useful for the planning of the surgical procedure. As the OPLL causes cord pressure from anterior, an anterior surgical procedures is ideal. However, technical difficulties related to exposure, resection of the OPLL, and, reconstruction and stabilisation of the vertebral column often preclude an anterior approach. When the compressive element extends for four vertebral segments or more, there is a preference for a posterior procedure as the condition resembles a cervical canal stenosis. However, in the presence of a pre-existing kyphosis, an anterior procedure is preferred. In practical terms therefore, the anterior approach is best performed when the cord compression extends for three vertebral segments or less, and in a kyphotic spine. A median corpectomy or an anterior segmental decompression are the surgical procedures available.
SURGICAL TECHNIQUE Shifting a patient with a cervical spine pathology to the operat¬ing table should be done with utmost care , and should be under the direct supervision of the surgical team. While ideally fibreoptic intubation may be practised, it is not essential as long as it is ensured that there are no vigorous neck movements during intuba¬tion. The endotracheal tube is preferably taken to the right side of the oral cavity. This takes the curve of the larynx to the left which helps retraction of the trachea during surgery. The patient is operated upon in the supine position with the neck in a minimally extended position. This extension is maintained either only by skull traction ,or by the addition of a soft roll at the nape of the neck. Hyper extension is to be avoided. The head is rested on a head ring of appropriate size and is kept straight and preferably not turned to either side. Some surgeons however prefer turning the head to the side opposite the side of approach to make the anterior border of the sternomastoid muscle prominent. Skull traction is applied before intubation and maintained through the surgical procedure. More
Head injuries are the major cause of mortality and morbidity especially following road traffic accidents. Care of head injured patients forms an important part of a neurosurgeons and a trauma surgeons work in all parts of the world. With increasing industrialization and more rapid means of transport the incidence of head injuries is increasing steadily. In more developed countries with fast moving traffic, head injuries are more severe and often associated with multiple injuries. In India there is a combination of fast and slow moving traffic, with traffic indiscipline and chaos a significant contributory factor. India’s fatality rate of 55 deaths per 10000 vehicles is amongst the highest in the world. Besides the number of deaths caused, head injuries are a major social problem due to the loss of young intelligent minds to trauma, a loss of man hours at work resulting in an increased burden to society and family. The only way to avoid this great social tragedy, is to find ways to prevent head injuries. Greater road discipline and the enforcement of traffic laws, public education of the fallout of major trauma, better on site medical and para-medical care with an efficient ambulance and first aid will go a long way in reducing the incidence and severity of head injuries. Two factors which will go a long way in the prevention of major head trauma are the compulsory wearing of helmets when riding or sitting pillion on two wheelers and the strict avoidance of driving after consumption of alcohol.
The final result of a head trauma is the cumulative effect of different forces acting on the head and the differential transmission of energy waves through the skull and the brain. The skull is a rigid hard container, that holds within it the soft jelly like brain. Between the two are the coverings of the brain, blood vessels and within the brain are the fluid filled ventricles. When a moving object hits the head, or when a moving head hits a stationary object, there are two mechanisms that are set into motion that result in brain damage. The first is the differential deceleration between the skull and the brain. The skull stops moving when it strikes a stationary object, while the brain continues to move forwards. This results in the brain hitting against the uneven and jagged surfaces of the inner surface of the skull base, resulting in injury to the brain. The greater the momentum with which the head strikes an object, the greater will be the differential deceleration and injury. The second mechanism is the force of impact, which is dissipated through the skull to the brain. Depending on the severity of the impact, a lesser or greater force is delivered to the skull. This force is then transmitted as energy waves through the bone and the brain, resulting in fractures, heamorrhage etc. The wearing of a crash helmet is aimed at reducing the impact force that reaches the brain, therefore lessening the actual brain injury.
The management f a head injured patient is in multiple stages:
The main objectives of management at the site of trauma are to establish the following: Airway, Breathing and Circulation or the ABC of acute care. These are of extreme importance as making sure of proper airway, breathing and circulation ensures that there is proper oxygenation of blood and that the circulation is good so that cerebral oxygenation is good. When these basic parameters are not taken care of at the site of injury, the patient often suffers a “second accident” resulting from hypoxia to the brain. The scalp is an extremely vascular structure and lacerations over the face and head often bleed tremendously. Bedsides the vessels of the scalp lie in the sub- aponeurotic layer, such that the arteries are held open even when there is a cut. Pressure over the edges of the scalp laceration or eversion of the scalp after the application of forceps on the galea will stop any bleeding immediately. Similarly any cut or laceration anywhere else in the body should be looked for and the bleeding should be stopped, at least temporarily, by appropriately placed tourniquets and , or pressure dressings. Once the ABC are looked at and ensured, the next step is to stabilize the patient for transportation to the hospital. The conscious level of the patient is to be noted and any obvious bleeding is to be controlled with pressure bandages.
Approximately thirty percent of all major poly and head trauma are associated with injury to the cervical spine. In all cases of trauma it must be assumed that the patient has suffered a cervical spine injury until it is proved negative. This means that the patient should not be immediately bundles into any available vehicle in any manner possible. A cervical collar or support and a backboard are mandatory. These will ensure that during shifting there is no inadvertent movement of the cervical spine, preventing a disaster. If the ideal collar or backboard is not available on site, one can use any available material temporarily so that the purpose of splinting the spine is served.
At the hospital, the team experienced in the management of head injury and poly trauma takes over the care of the patient. Once again it is important that the patient is first stabilized before anything else is done. Once stabilized, the conscious level and pupillary reaction are looked for, as well as the presence or absence of long bone fractures, and abdominal rigidity. As a protocol, there should be radiological screening of the entire spine, a non- contrast CT scan of the brain and ultrasound of the abdomen performed for all cases of poly trauma. The anesthetist, neurosurgeon, general surgeon and orthopedic surgeon form the trauma team and assess the extent of injuries, and formulate the plan of action for each case.
Indications for Neurosurgical intervention in a case of head injury include deteriorating conscious level and, or, papillary dilatation associated with an intracranial hematoma (extradural or subdural), cerebral contusion, or cerebellar hematomas. Diffuse cerebral edema often associated with multiple petechial hemorrhages all over the brain are best treated with anti-edema measures and ventilation with paralysis. Steroids have no role in the management of head injuries. Ventilation with paralysis works by reduction of the carbon dioxide content of the blood (PaCO2), which controls cerebral blood flow. The aim of ventilation is to keep the PaCO2 at about 25-30 mm Hg for the first 48 hours and then slowly bring it to normocarbia (40 mm Hg) after that.
Enforcing traffic discipline is the best way of doing this. Crash helmets have to be made compulsory for all riders and those sitting pillion on two wheelers (whatever the type). Similarly seat belts should be worn in all cars. Social awareness of the cost involved in the management and waste of precious life associated with head injuries must be increased. Society has a duty to perform if young productive lives have to be saved from the clutches of head injuries. More
The whole world has come together for the purpose of fighting a War against Terrorism. No nation has been left untouched by the events of terror that started on September 11th 2001 and continued into December 2001. Hitherto unfriendly nations found a common table to sit around and it appears as though the door leading towards the utopic state of the global nation is just opening.
What we forget is that terrorism come is many shapes and sizes, and that when there is a chronic state of terrorism , it becomes a way of life. This is also true of what is happening on the roads of Chennai. Terrorism has become a way of life on the roads and most of us have accepted this state. The road is the battlefield – the terrorists are the drivers – the victim is society. We remain mute and choose to turn a blind eye at the situation – hoping and firmly believing that we ourselves will never fall victim to the terror.
Traffic on Chennai roads is for the strong hearted and those with quick reflexes. The bus that thunders down the lane, the over laden lorry that hurtles around a corner, the car that flies, the auto that perceptually tries to squeeze through narrow gaps, the two-wheeler that weaves through the traffic, the cyclists for whom there are no rules or signals and finally the fish-carts who are king of all they survey ---- these are the weaponsused by the terrorists. The terrorists themselves are normal members of our society, who turn into Mr Hyde once on the road. All the aggression within is brought forth – and then it is a battle for survival.
Numerous are the victims of this terror – death is a common commodity. Death and loss affecting mainly the youth and the prime of society. Doctors, lawyers, engineers, software personnel, graduates, students, teachers – all those who matter, all those who contribute everyday to our community – they are the victims. Indirectly, we all are victims. A unique situation where we are both the terrorist and victim.
MUST WE JUST SIT BACK AND WATCH ?? Must we not also stand up and fight against this terrorism on the roads of Chennai ? Must we also not resolve to stop this unnecessary loss of life and livelihood. Let us resolve toady that each one of us will try and make a difference.
T= Try not to overtake on the left
E= Educate on the use of Helmets and Seat Belts
R= Relax at the Red light
R= Reach for the accelerator only after the green light comes on
O= Outright NO to Alcohol and driving
R= Reduce the speed at which you travel