.

OSTEOPOROTIC COMPRESSION FRACTURE: SALIENT POINTS

2007-10-26T22:44:00.000+05:30

*most common spine fracture in the emergency dept.
* female > male
* sudden onset pain in midback after a simple maneuvre such as coughing or lifting of weight
* 20% have asymptomatic fracture
* neurological deficit is rare after simple compression fracture
* 3 patterns of fracture ---> wedge, codfish and vertebra plana type
* CT should be taken if middle column involvement is suspected
* suspect burst fracture if interpedicular distance is increased or posterior vertebral height is decreased

* Admission if:
severe pain
ileus
urinarty retention
neurological comlications

* Bracing is offered to patient and he is then mobilised
* BMD is must for all osteoporotic fractures and approprite treatment is then instituted
* brace for 6-12 weeks
* after that----> extension exercise programme and low impact aerobics
* If significant pain after a few weeks---->Vertebroplasty is a good option
* Kyphotic deformity aftre repeated compression fractures---->ribs impinge on the pelvis,poor posture, protuberant abdomen, respiratory compromise

How to differentiate between osteoporotic fracture and tumour:

Patient with tumour has:
* severe pain and any movement is painful
* neurological signs are present
* plain x-ray shows: cortical destruction loss of pedicle compression fracture above T-7 or below L-2
* past H/O malignancy*MRI shows: obliteration of marrow cavity, with no fatty marrow left cortical margins are gray and mottled soft tissue mass outside the vertebral body causing cord effacement skip lesions gadolinium not a reliable choice to differentiate between benighn and malignant
* bone scan is useful to differentiate between benign and malignanat tumours* CT-guided biopsy is necessary if doubt persists

D/D OF SEVERE ACUTE BACK PAIN IN DIFFERENT AGE GROUPS

2007-10-26T22:42:00.000+05:30

Infancy and Adolescence:
* Vertebral Osteomyelitis
* Osteoid Osteoma
* Spondylolysis
* Scheurmann disease

Young and Middle age adults:
* Premature disc degeneration
* spondyloarthropathy
* Trauma

Old Adults:
* Disc degeneration
* exclude other causews

Old Patients:
* Metastasis
* Infection
* Osteoporotic compression fracture

QUICK TIPS ABOUT SURGICAL REDUCTION OF SPONDYLOLISTHESIS

2007-10-26T22:39:00.000+05:30

Ref: Frymoyer

*Surgical reduction of spondylolisthesis is usually reserved for patients with high-grade dysplastic spondylolisthesis as defined by Marchetti and Bartolozzi
*The primary pathology addressed by reduction is significant lumbosacral kyphosis. Improvement in the accompanying translation is a by-product of correction of the kyphosis and is to be expected.
*Elements: exposure---->laminectomy------->complete exposure of 2 roots above ane below-------->complete discectomy and scral dome excision--->decorticzation of opposing surfaces ofL5 and S-1------>ant. graftting and titanium mesh cage--->place peicle screws---->distract, placethe rods and compress------>posterolateral bone grafting

* Goals: anterior column load sharing reestablish the posterior tension band negation of lumbosacral shear forces

*which x-rays? Thirty-six–in. erect anteroposterior and lateral radiographs of the entire spine (including the femoral heads) are the basic required films.Flexion extension lateral radiographs are of little value.A magnetic resonance image (MRI) without contrast of the lumbar spine is quite valuable. The MRI depicts the anatomy of the lumbosacral disc as well as the anatomy of the sacral dome, guiding the resection of the sacral dome. The posterior inferior lip of L-5 may provide an impediment for placing a structural graft into the lumbosacral space; this is usually seen on the MRI.

*The transforaminal lumbar interbody fusion (TLIF) approach is performed.

*Creation of a physiologic flap of annulus------>A medial-based rectangular flap is created with the scalpel, taking care to protect L-5 roots. A stay suture of 2-0 silk is placed. This flap is then used to retract the S-1 root medially while protecting it. An excellent window into the lumbosacral space is now present. Figure 4 is an illustration of the exposure via the transforaminal technique described. The physiologic retractor afforded by the posterior longitudinal ligament and annulus is demonstrated.
*Morselized autograft is then placed in the anterior one-third of the interspace and impacted.
*Polyaxial screws are preferred to facilitate rod placement.
*With all screws in place, an appropriate length rod is selected and bent to appropriate sagittal contours. A lordotic configuration is usual. The rod is placed in the sacral screws first, and the closure mechanism is tightened.
*The cantilever maneuver using the rods attached to the sacral screws has the primary function of producing lumbar lordosis, using the Harms titanium mesh cages as a fulcrum. This decreases the lumbosacral kyphosis and the slip angle. This maneuver also decreases the lumbosacral translation.Application of compression between the L-5 screws and the S-1 screws has additional biomechanical functions. Compression loads on the anterior structural grafts may perhaps enhance anterior arthrodesis. Compression also increases lumbosacral lordosis production, using the structural cages as a fulcrum.
*Platelet-rich plasma provides a good adhesive medium to prevent scattering of the morselized fragments. An alternative is multiple strips of corticocancellous bone from the iliac crest.

QUICK TIPS FOR THORACIC PEDICLE SCREWS

2007-10-26T22:34:00.000+05:30

*pedicle screw insertional techniques :
freehand
fluoroscopically assisted
computer-aided
open-lamina K-wire assisted

*two trajectories have been described
anatomic trajectory
straight-ahead trajectory

*three anatomic characteristics of the pedicle important before insertion pedicle diameter angle of the trajectory length of the trajectory

*Entry Points:

Proximal thoracic( T-1-4 ) junction of proximal transverse process and lamina medial to lateral pars

Mid-Thoracic ( T-5-8 ) junction of downslope of proximal transverse process and lamina at the base of superior facet, medial to lateral pars

Lower Thoracic ( T-9-12 ) Downslope of bisected transverse process at the junction of transverse process and lamina at the same level as lateral pars.

Freehand technique using straight-ahead trajectory:

* both uni and multiaxial screws can be used
*posterior spine is dissected till exposure of transverse processes
*partial facetectomy done for the inferior facet
*use acorn-tip burr for making the hole, look for a cherry red spot that shows that the tip is in the cancellous bone of the pedicle
*2 mm curved thoracic gearshift pedicle finder is used to make the track for screw
*probe is pointed initially laterally and then near the base of the pedicle medially
*tip of probe should meet the resistance of the cortical bone of body
*signs of screw malposition: screws that overlap screws that are long screws that cross the midline screws that do not line up with the pedicle outline screws that do not follow curvature of spine
*after all screws are passes, stimulate them with EMG to evaluate the potential neurological impingement
*replace loose screw with a screw of bigger diameter

OSTEOPOROTIC COMPRESSION FRACTURE: SALIENT POINTS

2007-09-30T07:20:00.000+05:30

BIOCHEMICAL MARKERS OF BONE TURNOVER

2007-09-25T20:08:00.000+05:30

*alkaline phosphatase --If the alkaline phosphatase level is elevated, fractionation of this enzyme is helpful, as isoenzymes are secreted by several tissues, including bone, liver, kidney, and intestine.

*Urine hydroxyproline and hydroxylysine-- There is an elevated urinary excretion of hydroxyproline and hydroxylysine; both are degradation products of bone's organic matrix. Patients with Paget's disease can excrete up to 20 times more hydroxyproline than normal persons.

*pyridinoline cross-link assays-- important components to measure bone resorption

*calcium excretion in the urine -- Calcium excretion remains an important method for determining the rate of bone loss, and the 24-hour urine collection is a means for determining calcium and phosphorus balance. If calcium excretion in the urine is increased, treatment may be indicated to augment total-body calcium retention.

*Phosphorus excretion -- indicates the effects of PTH on the kidney and is usually elevated when the PTH activity is high.

*carboxyglutamic acid in the serum or urine/ osteocalcin -- low-molecular-weight protein synthesized only by osteoblasts and secreted directly into the circulation. Measurement of the protein in serum or urine is indicative of bone turnover

*PTH, and the vitamin D metabolites -- These more expensive tests should be reserved for those patients in whom a specific abnormality is suspecte

*serum protein electrophoresis -- to rule out an occult lymphoproliferative malignancy such as myeloma. This condition is frequently a cause of spinal pain and bone loss and has been shown to mimic osteoporosis radiographically.

PAGET'S DISEASE AND SPINE

2007-09-24T19:42:00.000+05:30

*the second most common metabolic bone disturbance in the United States, after osteoporosis

*prevalence of approximately 1 in 1,000 persons

*the vertebrae, pelvic bones, and femora are the most common

*pathologic lesion is characterized by an excess of hyperactive osteoclasts and osteoblasts, with an intense increase in bone resorption, marrow replacement by hypervascular fibrous tissue, and a haphazard attempt by the body to regenerate bone .

*new bone synthesized to replace the bone that has been lost appears as a disorganized, woven bone tissue and is of poor quality .

*increased cellular activity and turnover of bone matrix in Paget's disease is evidenced by increased urinary output of collagen breakdown by-products

*Presentations:
1.subclinical case is discovered when a patient has a radiograph taken or a serum alkaline phosphatase level measured for an unrelated reason
2.an obvious bony deformity, pain, and extraskeletal involvement
3.high--output heart failure may result from an arteriovenous fistula that develops in the hypervascular pagetic bone
4.Back pain has been reported to occur in 11 to 43% of patients who have Paget's disease involving the spine .central or lateral stenosis, nonspecific syndrome of stiffness, ache and fatigue due to arthritic changes in the facet joints, Pathologic fractures , the most common sites are the fourth and fifth lumbar vertebrae . When these vertebrae are severely affected, spinal stenosis is a common finding.

*arterial steal phenomenon, whereby hypervascular pagetic bone “steals” blood from the neural tissue, is also a possible etiology for the observed symptoms

*direct compression of the vascular supply of the neural tissue

*Malignant degeneration occurs in 1 to 10% of patients with Paget's disease and is the most serious complication of this disorder.The most frequently occurring malignant tumors in pagetic bone are osteogenic sarcoma, followed by fibrosarcoma. Other less common tumors include chondrosarcoma, malignant fibrous histiocytoma, and reticulum-cell sarcoma. The most common site for pagetic tumor involvement is the femur, followed by the humerus, pelvis, and tibia.

*The DIAGNOSIS of Paget's disease is based on history, physical examination, radiographic evaluation, and measurement of biochemical markers.

*Because urinary measurement of hydroxy-proline or hydroxylysine is expensive and cumbersome, however, the measurement of alkaline phosphatase has become the preferred laboratory test.

*There is an elevated urinary excretion of hydroxyproline and hydroxylysine; both are degradation products of bone's organic matrix. Patients with Paget's disease can excrete up to 20 times more hydroxyproline than normal persons .

*A urinary assay has been developed that measures the pyridinium derivatives hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), which are intermolecular cross-links of collagen collectively known as pyridinoline cross-links .

*Using a specific HP and LP assay, Uebelhart et al. showed that the urine of patients with active Paget's disease had a 12-fold increase in pyridinolines .

*HP and LP decrease significantly after treatment with aminopropylidene bisphosphonate, a potent inhibitor of bone resorption, which indicates that urinary excretion of HP and LP reflects only collagen degradation occurring during osteoclastic resorption and not the degradation of newly synthesized collagen.

*Bone biopsy is rarely needed for diagnosis , opnly when malignant degeneration is suspected.

Treatment:-

basis: suppression of osteoclastic activity.

approved agents: salmon and human calcitonin and several bisphosphonates. Plicamycin (previously mithramycin), although not approved by the FDA for the treatment of Paget's disease, is available by prescription.

indication for treatment and the choice of therapeutic agent continue to be debated. Currently, the most widely followed indication for initiation of treatment is a serum alkaline phosphate level that is at least three times normal.

Treatment is intended to alleviate patients' symptoms by suppressing osteoclastic activity. A decline in alkaline phosphatase or pyridinium cross-link levels of 50% or more can ameliorate symptoms in up to two-thirdsof patients. Bone pain, headache, and low back pain are most likely to be relieved. Conversely, pain due to arthritic changes and bony deformity does not improve with medical treatment.

Human and salmon calcitonins are available as subcutaneous or intramuscular injection (salmon calcitonin is also available as a nasal spray). Doses generally range from 50 U three times per week to 100 to 200 U per day in severe cases. Symptoms may begin to improve over several weeks, and biochemical markers begin to decline after 3 to 8 months. Decreasing effectiveness over time has been observed. Side effects are few and minimal, as noted previously.

Plicamycin is a potent and toxic therapeutic modality that is indicated only for severe refractory cases, such as those involving spinal cord compression. It is administered intravenously and is infused every second to third day for five to ten infusions per cycle. Its action is to inhibit osteoclastic activity, as well as reduce the hypervascularity associated with Paget's disease.

Alendronate and risedronate can be used at doses higher than those used for osteoporosis. For example, whereas a daily dose of alendronate for osteoporosis is 10 mg, for Paget's disease, a 40-mg dose is recommended. Pamidronate (Aredia) has recently been approved for the treatment of hypercalcemia of malignancy and has been used to treat refractory Paget's disease. It is administered as an intravenous infusion, and its use requires careful medical monitoring.
Other therapies, such as gallium nitrate, also have been used in experimental settings.

EMG AND NCV--BASICS

2007-09-24T19:18:00.000+05:30

when to do it?

*discrepancy between clinical findings and neuroradiologic imaging [magnetic resonance imaging (MRI), computed tomography (CT), myelogram] that often occurs in patients with back pain accompanied by extremity pain, numbness, or weakness
*all forms of nondestructive pathology noted on spinal imaging tests
*When imaging studies show multiple levels of spinal pathology consistent with nerve root compression
*certain patients with well-defined neurologic deficits and corresponding imaging studies to determine whether the deficits are acute or chronic
*To know if neuronal symptoms in the extremities are due to more peripheral neuronal entrapment (e.g., carpal tunnel syndrome in the arms or peroneal neuropathy in the legs) rather than an observed spinal pathology

The purposes of these tests are not only to document the presence of radiculopathy and differentiate it from more peripheral neuronal deficits, but also to determine its segmental level and to give some estimate as to degree and chronicity of the nerve root dysfunction.

There are 2 mechanisms by which the nerve fibres react to the variety of pathology

1.loss of myelin and axon both

2. demyelination with intact axon

EMG:- It is mainly affected by axon loss

NCV:- It is mainly affected by demyelination.

Needle EMG:
*the most useful electrodiagnostic procedure for the evaluation of radiculopathies

*A bipolar or monopolar needle electrode is inserted into a muscle, and the electrical activity in the muscle is measured under various functional conditions

*all EMG manufacturers use digital monitors

*A normally innervated muscle is quiet at rest, and the recording shows a flat or straight line

*If the muscle is denervated, as may occur in radiculopathy, there may be ongoing spontaneous activity at rest. The abnormal spontaneous waves may be in the form of fibrillation potentials, positive sharp waves, or fasciculations

*Fibrillation potentials and positive sharp waves tend to develop in the muscles within the myotome in a proximal to distal sequence.Following onset of an acute lesion, they may be found after 6 or 7 days in the paraspinal muscles, after 3 weeks in the proximal extremity muscles, and after 5 to 6 weeks in the distal extremity muscles. For that reason, sampling the paraspinal muscles as well as the limb muscles is important.

*spontaneous activity in the paraspinal muscles indicates that the lesion affects the fibers of the posterior primary ramus and is therefore within or near the intraspinal canal .

*Often, the paraspinal muscles do not show spontaneous activity even in patients with proven radiculopathies.

*mech. of polyphasic waves:When a muscle is denervated, adjacent nerve fibers will attempt to reinnervate the affected muscle fibers through sprouting of collateral axons, which then migrate to and make synaptic connections with the denervated muscle fibers. This phenomenon results in higher amplitude (giant) motor unit potentials with increased duration and number of phases (polyphasia).

Conclusions from EMG:

*the differentiation of acute from chronic denervation can be made. The acute changes result in the fibrillation potentials, positive sharp waves, and fasciculation during the resting phase, whereas the chronic changes result in the larger or giant motor unit potentials with polyphasia.
*severity of nerve dysfunction can also be estimated, although this is relatively crude. The quantity of denervation potentials allows some assessment of the extent of the radiculopathy, but perhaps more important is the nature of the recruitment and the degree to which a muscle is able to generate an interference pattern. A muscle that is affected only slightly may show abnormal potentials but still may be able to generate a full interference pattern. A more severely denervated muscle only generates a weaker interference pattern.

*the level of a radicular injury can be localized within one or two segments by means of EMG. This requires testing multiple muscles in the extremity and paraspinal muscles and correlating the pattern of abnormalities observed with the known muscular distribution of each nerve root.

H Reflex:

*monosynaptic spinal reflex with both motor and sensory pathways traveling through the S-1 nerve root by large diameter nerve fibers

*The reflex is elicited by recording the electrical response generated by the soleus muscle on stimulation of the posterior tibial nerve in the popliteal fossa

*Depending on age, leg length, and other factors, this stimulation is followed in approximately 23–32 milliseconds by a second contraction of the soleus muscle, which is the H reflex response (Fig. 4). The H reflex first increases in amplitude with low stimulus intensities and then decreases in amplitude as the stimulus intensity increases. An absent H reflex correlates well with an S-1 radiculopathy (2) and an absent Achilles deep tendon reflex.

*Problems with H reflex:

1.no changes in mils s-1 radiculopathy

2.experienced myographer and fastidious technique is required

3.affected only in s-1 root lesions

4.not synonymous with s-1 root since lesion anywhere along the sensory/ motor pathway or spinal cord can give ris eto the abnormal response 5.remains abnormal indefinitely, so not of any use in recurrent disc 6.absent in polyneuropathies and old patients

* it is complementary to EMG and confirms acute s-1 root injury even before EMG.

F Response:-
*The F responses are late responses that can be recorded from a muscle after maximal stimulation of its nerve

*The response is often inconsistent and of small amplitude when compared to the direct motor response and can show considerable variation in latency. For this reason, it is necessary to elicit at least ten responses for every tested nerve and to use the shortest or minimal latency

*The advantage of the F response is that it becomes abnormal immediately after an injury and may be the only early electrodiagnostic abnormality in patients with a radiculopathy

*F response studies are disappointing in patients with clinically unequivocal cervical and lumbar radiculopathies

NCV:-
*Motor and sensory nerve conduction studies are usually within normal limits in the patient with pure one-level radicu-lopathies

*Even when clinical examination strongly suggests a radiculopathy, it is still important to consider motor and sensory peripheral nerve conduction studies

*The primary shortcoming of EMG and F responses is their ability to detect a spinal cord lesion or a purely sensory radiculopathy

*TYPES:

Large mixed-nerve SEPs

Small sensory nerve evoked potentials

dermatomal somatosensory evoked response or potential (DSEP)Pudendal Evoked Responses

Magnetically Evoked Potentials

* BENEFITS:

1.directly assess the physiologic integrity of the spinal nerve roots, thereby providing information of both diagnostic and prognostic relevance

2.noncompressive radiculopathies

3.differentiating between radicular and more peripheral sources of neuronal symptoms or clinical deficits

4.documenting the presence of lesions affecting the spinal cord and the pudendal nerve that may be difficult to assess from the neurologic examination

*LIMITATIONS:-

1.does not detect all compressive radiculopathies

2.time dependent, Studies may be falsely negative if they are performed too early or too late in the course of the radiculopathy

3.with chronic radiculopathies, the EMG may be unrevealing, because muscles that had previously contained fibrillation potentials for a time after the onset of radiculopathy may have become completely reinnervated and therefore do not show any spontaneous activity

4.cause of the causative pathologic process cannot be determined, regardless of the electrodiagnostic procedure used in determining the radiculopathy

5.Although the root affected may have been determined, the anatomic site of the lesion, especially with regard to disk level, can only be estimated

6.In the end, it is the correlation of the patient's symptoms, clinical examination, electrodiagnostic consultation, and imaging studies that leads to the most accurate diagnosis of the patient with spine and extremity symptoms.

NONOPERATIVE MANAGEMENT OF BACK PAIN: A QUICK REVIEW

2007-09-18T19:00:00.000+05:30

Acute Low Back Pain (0 to 4 Weeks)
*symptomatic relief with NSAIDs or acetaminophen

*activity advice recommending return to normal activities as soon as tolerable

*short-term opioid

*muscle relaxant for as long as 1 to 2 weeks

*education of the patient regarding the generally favorable natural history of the problem

Subacute Low Back Pain (4 to 12 Weeks)
*reevaluation

*appropriate laboratory and imaging studies

*active exercise-oriented physical therapy is recommended both for its reconditioning and educational benefits

Chronic Low Back Pain (More than 12 Weeks)
*interventional investigation may identify a potential precise pain generator

*Exercise improves pain intensity and functional status in persons with chronic back pain and is the cornerstone of management

*Pure analgesics

*Tricyclic antidepressants may be useful as adjuvant analgesics

*Manipulation, acupuncture, or massage may be of some benefit as adjunctive treatment in selected patients with chronic back pain

*education

ACTIVE SLR TEST FOR INSTABILITY OF SPINE

2007-09-16T20:22:00.000+05:30

How to perform?

Active SLR test is perfomed with the patient in supine position and both his hands behind the head. Then he is asked to lift both the legs at the same tie without bending the knees.The bakpain reproduced by this maneuvre is taken as apositive test.

What does it show?

It indicates the instability phase of the degenerative spine disease with weak abdominal muscles .

Mechniasm:

Lifting of legs stright---->rotation of pelvis anteriorly---->hyperextension of spine due to weak abdominal muscles--->increased intradiscal pressure------>reproduction of the backpain----->positive test.

Implications:

* pt has weak abdominal muscles and during conservative therapy, the pt. should strngthen the abdominal muscles and wear a corset that raises the intra-abdominal pressure and supports the spine better.

*Pt should avoid extension strains on spine and follow a flexion exercise programme .

*If the instability indicated by the test does not respond to the conservative therapy, then the surgery involves fusion of that motion segment.

CURRENT CONCEPT OF REFEERED PAIN

2007-08-22T20:27:00.000+05:30

Obtained from Kellgren , Mooney and Anderson.

Reffered pain is

* a very diffuse sensation in their legs

* bilateral in nature

* not associated either with any radicular pattern or any root tension irritation or compression findings

* provided that those patients do not have spinal stenosis on CT scan or MRI, they probably have referred pain.

It is perceived as one of the two types of discomfort:

*deep discomfort felt in a sclerotomal or myotomal distribution

* it may be superficial in nature and felt within the skin dermatomes

Concept of trigger zones:

Somewhere in the nervous system is a convergence and summation of nerve impulses from the primary painful area. This is probably lamina 5 in the dorsal horn. The stimulation of this lamina opens a gate and allows central dispatch of the pain message and distal referral of other sensations that indicate referred pain. The essential feature of the relationship between the site of the pain and the distal referral is the common segmental origin of the sensory innervation for both the origin and the distal referral site. Some of that commonality may occur in the complicated ascending pathways in the spinal cord. You can increase the painful sensation by touching the sites of referred pain. These areas are known as trigger zones, and, through various methods of stimulation and anesthetization, referred pain can be altered.

TIPS, TRICKS ABOUT TITANIUM MESH CAGES

2007-08-18T20:59:00.000+05:30

A titanium mesh cage provides a biomechanical stability for the anterior thoracic arthrodesis.

KEY PRINCIPLES:

A cylindrical mesh cage like Harms' cage provides biomechanical stability with bony ingrowth potential. Fenestrations in the cage incease the graft-host bony surface area for maximal bony graft incorporation.

INDICATIONS:
All anterrior spinal pathologies involving decompressive procedures.

CONTRA-INDICATIONS:
pyogenic infections of spine- avoid metallic implants anteriorly; post. implants can be us

TIPS/ TRICKS:

Place the cage as posteriorly as possible near the middle column.

Use the harvested rib graft for packing the inside of the cage.

Preserve the subchondral bony end plates.

The ends of the cage can be trimmed to achieve desired cage configuration.

Internal rings can be fitted at the neds of the cage whicj increas the stability of the cage.

The serrated border increase the anchoring of the cage.

The bone graft should be packed around the cage.

A single anterior rod construct increase stability of cage.

Large ant. defects need post. column support.

PMMA is an alternative to the cage.

Classification of instabilities

2007-08-12T12:47:00.000+05:30

Frymoyer has described a classification system for degenerative segmental instabilities that is an expansion of an earlier classification system .It is based on radiographic findings, as well as a history of previous spine surgery . The underlying concept is that segmental instability is best diagnosed when the deformity progresses over time. Indeed, the classification was based principally on such progressive deformities, rather than abnormal motions and translations identified on a single dynamic flexion-extension radiograph. A primary instability is one that cannot be attributed to any previous interventions (i.e., surgery, chemonucleolysis). Secondary instabilities are those that were created or exacerbated by an intervention.

Type I: Axial Rotational Instability
Axial rotational instability has a rotational malalignment as a major part of the deformity. Because cadaveric studies have shown that degenerative spondylolisthesis can have combinations of rotatory deformity, lateral bend, and translation , Frymoyer suggests that this and type II defects might be the same. Clinically, patients complain of recurrent, episodic low back pain provoked by twisting motions. Radiographically, this is manifest by malalignment of the spinous processes as well as pedicle rotation. Myelograms have been reported to show a pedicle-to-pedicle defect .

Type II: Translational Instability
Translational instability is synonymous with degenerative spondylolisthesis. Forward displacement of the cephalad vertebrae is the predominant deformity, although some rotational component can exist. Patients may complain of recurrent episodes of back pain along with an extensor lag. Classic radiographic signs described by Knutsson and Macnab, such as traction osteophytes and vacuum discs, are associated with this type of deformity. Women are affected five to six times more often than men, and the instability usually occurs after the age of 40 years. It occurs three times more often in African American women than in white women and usually involves the L4-5 interspace. Facet joint angulation has been implicated as a cause of the deformity.

Type III: Retrolisthetic Instability
Retrolisthetic instability is manifest by posterior displacement of the cephalad vertebra, posterior disc space collapse, and facet subluxation. The symptoms, which may include low back pain and nerve root signs, are most prominent in extension. Radiographically, the retrolisthesis increases with extension as well.

Type IV: Degenerative Scoliosis
The curve seen in this degenerative scoliosis is usually less than 40 degrees and is associated with central and lateral recess stenosis. The combination of the curve with degenerative disease of the disc and facets reduces canal size, and thus can be associated with central and lateral stenosis. Symptoms usually consist of low back pain with or without neurogenic claudication and/or radiculopathy.Patients with stenosis due to degenerative scoliosis, however, generally do not get relief from sitting .

Type V: Internal Disc Disruption
Various authors have tried to study the relationship between instability and disc disruption but have not found a definitive link. Soini et al. found no association between disc degeneration (as assumed by discography) and abnormal angular movement. It is not clear at this time what the relationship is between disc disruption and clinical instability.

TIPS FOR LAMINOPLASTY OF CERVICAL SPINE

2007-08-08T22:58:00.000+05:30

The following are the practical tips, tricks and hints from Hirabayashi.

What is it?
Laminaplasty is an operation to enlarge the spinal canal simply and safely to promote the consolidation of the spinal laminae at the laminar hinge.

Key Principle:

* It preserves the laminae and spinous processes and prevents dural adhesions
*maintains the attachment of the post. spinal muscles
* adequate decompression can be achieved without sacrifising the spinal stability due to post spinal ligament complex

When to think of Laminaplasty?
* cervical canal stenosis due to dvelopmental, spondylotic and OPLL causes when the alignment is lordotic or straight
* some pts. of tumour of spinal cord

C/I: established kyphosis

pre-op:

do CT and MRI
look for *thickness of laminae
* shape of spinal canal
*localise spinal lesions

TIPS AND HINTS:

*Keep the head-up tilted position to keep the neck flexed in a horizontal plane

*Make the hinge-side gutter after all the procedure on the open side to avoid the breakage of the hinge

*if the hinge breaks then laminectomy should be done

*make a drill hole on the level caudal to the distal laminaplasty limit and bend the tip of the spinous process on the hinge side in order to dissipate the tension in hte inter and supraspinous ligaments

*use a diamond burr than a steel burr to avoid the injury to the dura

*remove the thineed cenral wall of the gutter using a Kerrison rongeur

*make the gutter on the hinge side a little laterally in order to make it more stable

*when making the hinge gutter, occassionaaly apply a bending force to the spinous process to check the stability of the hinge

*stay sutures are taken through the facetal capsule and deep muscles before the hinge is opened

*after the hinge is opened, the position of neck is changed form flexed to extended to maintain the lordosis

*use the tip of the rongeur to elevate the laminar door

*stay sutures are passed through the interspinous ligamensts and tied around hte spinous processes

PROBLEMS:

epidural bleeding-- pack off with fibrin

hinge break

post op- paresis at C-5-6 usually resolves by 5-6 months

What we should look when examining movements of spine?

2007-07-31T22:31:00.000+05:30

The movements at the spinal joints are a part fo a routine clinical examination, however, what are the things to be noticed during checking them?
I have enumerated the following points which I feel are important, comments and additions are welcome.

SUBJECTIVE:

* Pain during movements
flexion -- think of prolapsed disc
extension -- think of facetal arthropathy

*Feeling of giving way
Think of instability in lumbar spine

OBJECTIVE:

*Range of motion
Important to record and document to asseess severity and then to assess progress

*Rhythm
Any deviation from normal rythm during flexion and extension such as jerky movements and
extension catch are indicative of instability.

*Schober's or modified Schober's test
To diffentiate between organic and functional disease of lumbar spine

LINKS TO VARIOUS VIDEOS ABOUT SPINAL SURGICAL PROCEDURES

2007-07-29T14:04:00.000+05:30

Here are the various links to the spinal surgery videos from http://www.or-live.com/

Right-click and open the video in another window.

* Anterior cervical fusion for cervical canal stenosis

* Minimally invasive lumbar spine fusion using Meditronics CD-Horizon Peek rod system

*Management of chonic neck pain and laminoforaminotomy

*Minimally invasive transforaminal lumbar spine fusion

*Another video of TLIF for lumbar spine

*Minimally invasive lumbar discectomy

*Percutaneous Vertebroplasty

*Total disc replacement using SB-charite prosthesis

*TLIF for chronic back pain

*PLIF with instrumentation and bone graft

*An innovative herniated disc repair sytem--METRx system

*Anterior cervical descectomy and fusion

*Sextant rod sytem for MIS-PLIF

* Spinal repair-Vertebroplasty

I will be adding more videos in this link...keep watching.

Why is spinal canal stenosis painful?

2007-07-29T10:14:00.000+05:30

The pathological changes associated with LCS from any cause have been constriction of the nerve roots and the dura and then become adherent due to arachnoid changes, degeneration and demyelination with regeneration of nerve tissue, absent arterioles at the site of constriction, collapse of venules and formation of A-V shunts at the proximal end. Synovial cysts may form and compress the nerve roots and become adherent to the dura.
The symptoms of LCS arise from a combination of mechanical and ischemic metabolic factors.

The events progress as follows:

mechanical contriction of the neural lesions----> impairment of free flow of CSF and consequent adhesions----->venous obstruction and A-V shunts----->ischemia and metabolic end-products act together------>large sensory fibres more susceptible than smaller motor fibres------>ectopic nerve impulses are fired------> variety of paraesthesiae------> long-term compression causes fibrosis and adhesions----> neurological weakness occurs.

The symtoms are more common in the elderly since with ageing the nerves are more susceptible to compression.

Watch the animated video of spinal stenosis HERE

Cervical Facet Joint Injections

2007-07-27T20:56:00.000+05:30

BASIS:
Cervical facet or zygapophyseal joints are plane synovial joints which allow motion across facets.
cervical facet joints are oriented in a plane 45 degrees from the coronal and sagittal planes and is obliquely oriented in the craniocaudal direction, slanting downward in a pattern often visualized as roofing shingles. The medial branch of the dorsal primary ramus provides sensory nerves to the joint and at the C-3 through C-6 levels courses along the lateral margin of the middle of the articular pillar .The third occipital nerve is an especially large branch and runs a more cephalad course being at the lateral aspect of the C2-3 joint. The C-7 medial branch is in the middle to upper articular pillar region, having been pushed upward by the large transverse process of C-7.The major cause of facet joint disease is osteoarthritis, which may lead to neural exit foramen encroachment with or without vertebral subluxation. The sensory nerves of the facets and surrounding tissues may become inflamed and result in local pain, nondermatomal radiation of pain, and focal tenderness.
HOW TO DIAGNOSE:
local pain over a facet joint
restricted range of motion
local tenderness
nondermatomal radiation of pain to the shoulder, back, or arm above the elbow
headache occassionally
Accurate localization of the symptomatic joint can usually be made by firm palpation to elicit focal tenderness.
Imaging is often not required.
TECHNIQUE:
Under IV sedation
No antibiotic prophylaxis
Under guidance of fluoroscopy, CT or MRI
No. 22 ( stiff and trajectory can be changed) or No.25 ( no local anaesthetic needed)
3 trajectories- posterior, posterolateral or lateral
2 angulations-cranial or caudal
no contrast since it causes delayed inflammatory reaction
Diagnostic--1/2 ml of lignocaine or bupivacaine in cavity and 1/2 ml on medial branch
Therapeutic-- add triamcinolone or betamethasone
avoid large volume since it may extravaste into epidural space and cause false positive test

COMPLICATIONS:
The most common are transient worsening of pain or vasovagal reactions
higher doses of local steroids cause anxiety in the elderly, elevation of glucose in diabetics, and abnormal menses in women
RELIABILITY:
In patients with a facet syndrome, diagnostic and therapeutic blocks can reduce the pain. This helps with diagnosis in difficult cases. The implication for successful surgery after the block, however, is unclear.

CT. EXAM. OF A SPINAL DEFORMITY

2007-07-24T19:48:00.000+05:30

Let us continue with the examination a spinal deformity.

HISTORY:

* look for obvious syndromes with associated nervous or renal disorders
*developmental milestones especially during first 2 years of life
*ask for previous operations or illnesses
* spinal deformity- onset, duration, progress, screening, function, gait, balance
*pain in back
* previous treatment - brace or surgery
*skeletal maturity - ask for menarche in girls and sec. sexual features in boys
max. risk during first 6 months affter menarche of progression

EXAMINATION:
posture of the child
manner of interactions with the parent or care provider

inspection in the standing position --
Body habitus - obese, tall, dwarf
Obvious asymmetries - back, shoulder, scapula, waist, ribhump
Cutaneous lesions
plumb line test - for balance of head over sacrum
LLD - measure limb lengths
Adam's test - in sitting position to eliminate effect of a LLD
sagittal curvatures
range of motion
passive side bending
clinical test of flexibility- passive side bending, clinical bending, traction test

palpation in standing position -
palpable step-off
lumbosacral kyphotic deformity
tight hamstrings
Adam's forward-bending test
truncal rotation
scoliometer - determine the ATR and the spirit level to measure in centimeters the height of the rib hump or lumbar prominence
gait or balance
heel and toe walking
Romberg's test
chest wall deformiries

full neurological examination -
higher functions
cranial nerves
motor system- tone, power, coordination
sensory - touch, pain, proprioception
reflexes - DTR and superficial, pathological
bladder and bowel function
special tests
root tension signs
signs of dural irritation
signs of spinal instability

LAB. STUDIES:
CBC, ESR
HLA-B27
ABG in severe curvature or neuromuscular curves
pulmonary function tests

RADIOGRAPHIC STUDIES:

To see - location, type and stage of deformity
36" film with entire spine including top of iliac crest

single AP view for diagnosis and follow-up

lateral view- pain or sagittal imbalance

oblique view - pars defects in standing position

special views - Stagnara view, bending and stretching views only before bracing or surgery

supine films - for better definition of structures

AVOID routine scoliosis series
-------------------------------------------------------------------------------------
Today's link:

The Radiology of Acute Cervical Spine Trauma
Access Here

HOW TO EXAMINE SPINE DEFORMITY

2007-07-20T22:07:00.000+05:30

Here are the excerpts from Weinstein's book about examination od a spinal deformity.

SCREENING FOR SPINAL DEFORMITY:
Screening has been defined as the presumptive identification of unrecognized disease or a defect by the application of tests, examinations, or other procedures that can be applied rapidly to sort out apparently well people who have the disease from those who probably do not.

when should screening for spinal deformity start?
* prenatal -- spina bifida, myelodysplasia
* neonatal -- signs of spinal dysraphism,
* juvenile -- idiopathic, developmental, neuromuscular
* adolescent -- idiopathic

School Screening:

population - 10-14 yrs. of age

screening technique:
* train the primary sceeners like nurses, interested teachers, educated laity, physical therapists, and occasionally physicians
* integrate with preventive care programmes
*educate students and parents with slide shows and videos
* conduct screenig at school nurses' office or physiotherapists room
* boys can be exposed, girls should use bras or bathing suit

points to watch for:

*asymmetry of neck, shoulders, ribs, waist, hips
* posture of head over pelvis
*prominenet scapula
* truncal shift
*limb length inequality
*Adam's forward bending test
*Bunnel's inclinometer or scoliometer to measure angle of truncal rotation(ATR)

referral criteria- if ATR > 5 deg.
- painful scoliosis
- skin anomalies over spine s/o spinal dysraphism
- dwarfness
- secondary sexual characteristics

scoliometer:
*Bunell 1948, also called inclinometer, idea from sailing in a boat
*To measure deformity in rotational plane
* Measures ATR or angle of thoracic inclination; angle is the construct between the horizontal and a plane across the posterior rib cage at the greatest prominence of the rib
*how to measure- Patients are placed in the forward-bending position (Adams test), and the degree of hip flexion is adjusted to place either the thoracic or the lumbar spine in the horizontal position
*efficacy: The scoliometer has a false-negative result rate of 0.1% and a high degree of sensitivity. It has been reported as an effective screening tool in the identification of children at risk for significant scoliosis (more than 10 degrees) . Ashworth found that adding the scoliometer to the Adams test increased the specificity of that test from 56% to 86%. Bunnell found that the mean Cobb angle in patients with 5 degrees of truncal rotation was 11 degrees of scoliosis, and for a truncal rotation of 7 degrees, the mean Cobb angle was 20 degrees. The recommendation was made, therefore, to refer all patients with an ATR of 5 degrees or greater because they are in the at-risk population for spinal deformity. Some authors have recommended increasing this cutoff to 7 degrees, but at the same time, concern has been expressed that some patients with curves greater than 20 degrees will not be picked up on initial screening.

So far for today, will post detailed examination of spinal deformity tomorrow.

HISTORY AND EXAM. OF SPINE PATIENT

2007-07-19T19:43:00.000+05:30

THESE ARE THE SALIENT POINTS TO BE ELICITED IN HISTORY TAKING FOR SPINE CASE.

HISTORY:

CHIEF COMPLAINTS:

1. BACKPAIN:

onset, duration ,progress

site, radiation, character, agg. and relieving factors, severity

mechanical/non-machanical

2. LEG PAIN:

referred / radicular / claudicant

uni / bilateral

exact dermatomal distribution / glove and stocking

pareasthesiae / numbness

agg. and rel. factors

3. WEAKNESS:

onset, duration, progress

location, symmetry, UL /LL

progressive / fluctuating / exercise-induced

4. SPHINCTER DISTURABANCES:

urinary frequency /incontinence /retention

incontinence of faeces / perineal numbness

5.DEFORMITY:

onset / progress / severity

chest / waist / shoulder-blade

sense of going off-balance

loss of height

cosmetic effect and psychological effects

PAST HISTORY:

similar episodes, treatmet taken

past surgeries and post-op. follow-up

conservative modalities tried

ETIOLOGICAL HISTORY:

Trauma: duration, mechanism, severity, effects, treatment

taken, surgeries, cons. modalities

Tuberculosis: h/o fever, cough, wt. loss

Medical illness

Primary malignancy

Age: osteoporosis, sec. malignancy

Associated cong. anomalies

MEDICAL HISTORY:

visceral back pain

ass. illness mimicking spinal pain

for fitness for surgery

peri-op. control

SOCIAL HISTORY:

type of work, compensation illness

smoking/ alcohol

FAMILY HISTORY:

idiopathic scoliosis and other syndromes

CURRENT FUCNTIONAL STATUS:

household / community ambulator

walking aids / bedridden

employed? compensation claims

extent of restriction of walking

improvement after cons. Rx

NOW FRAME D/D FROM HISTORY

2007-07-17T22:00:00.000+05:30

Hi All,
Today I am posting the liks to 2 textbooks on spine surgery. Hope you will fine them useful. These liks were found on internet and not uploaded by me.

1. minimally invasive spine surgery
Access Here

2. Master techniques of spine surgery
Access part 1 Here
Access part2 Here
Access part 3 Here
Access part 4 Here
Access part 5 Here
Access part 6 Here

Welcome to spine surgery blog

2007-07-17T21:51:00.000+05:30

Welcome to spine surgery blog. This blog has been started with the intention of sharing of knowledge about various aspects of spine surgery for fellows and residents-in-training who are interested in spine surgery. I am a qualified orthopaedic surgeon in Mumbai, India and currently doing a spine surgery fellowship course of 2 years in India. The interseted bloggers can share their cases, videos, links, e-books, articles, journals on this blog. Also, we can discuss the clinical cases and recent advances about spine surgery in this blog.Suggestions, comments, criticism, references about the contents in the blog posted by me are welcome.
Looking forward to your co-operation and contribution to this blog.