Biomedical subjects

S I Esses

Publications and source records attributed to S I Esses.

At least 19 recordsLinked to original sources

PubMed1995

Posterior interbody arthrodesis with a fibular strut graft in spondylolisthesis.

We reviewed the results of posterior interbody arthrodesis of the fifth lumbar and first sacral vertebrae with the use of a fibular strut graft in nine patients who had had a grade-III, IV, or V spondylolisthesis. The average age of the patients at the time of the operation was twenty-seven years (range, seventeen to thirty-two years). The average duration of the symptoms preoperatively was three years (range, nine months to eleven years), and the average duration of follow-up was three years (range, two to five years). The most common preoperative symptom was back pain, which was rated an average of 8.3 points (7, 8, or 9 points) on a visual-analog scale of 1 to 10 points. The average angle of the slip was 45 degrees (range, 15 to 70 degrees). Four of the slips were grade III, four were grade IV, and one was grade V. Postoperatively, the average pain score was 1.4 points (1, 2, or 3 points). This improvement was significant (p < 0.05, Student t test). All nine patients had roentgenographic evidence of osseous fusion at the one-year follow-up examination. Complications included a dural tear in one patient, a superficial wound infection in two patients, temporary weakness of the evertors of the foot in six patients, and transient decreased sensation along the dorsum of the foot of the donor leg in two patients.

Adult↗

PubMed1995

Conservative options in the management of spinal disorders, Part I. Bed rest, mechanical and energy-transfer therapies.

Current literature does not support the efficacy of solitary use of energy-transfer therapies, such as ice or heat treatments, or electrotherapy, for the treatment of idiopathic back pain. Bed rest does not alter the natural history of back pain, and in fact can be detrimental to optimal recovery. Mechanical therapies, such as traction and orthoses, have limited usefulness. Although orthoses do not appear to weaken the trunk, they also do not appear to alter posture out of the brace, do not consistently diminish back muscle action during activities, and do not immobilize the spine. There have been no conclusive studies to substantiate the solitary use of any of these forms of treatment, although some may be beneficial at times in an adjunctive role.

Bed Rest↗

PubMed1995

Conservative options in the management of spinal disorders, Part II. Exercise, education, and manual therapies.

At this time, evidence supports exercise as an efficacious form of treatment for individuals suffering from back pain. The incorporation of education regarding posture, body mechanics, and ergonomics as part of a progressive exercise program appears justified. While there is empirical evidence available for the use of biofeedback, there are no specific studies supporting its efficacy in the treatment of the spine. Manual therapies such as mobilization and/or manipulation appear to shorten the course of subacute back pain, but do not alter the natural history and do not appear to be efficacious as monotherapy for chronic back pain.

Biofeedback, Psychology↗

PubMed1994

Biomechanical testing of pars defect repairs.

STUDY DESIGN: Human lumbar vertebral bodies were used to biomechanically test three different pars interarticularis defect repair techniques. A posteriorly directed force was applied to the inferior facets so that a bending moment was created across the pars. OBJECTIVES: The stiffness and strength of each type of repair was measured and compared with the intact values. SUMMARY OF BACKGROUND DATA: The Buck screw provided both the stiffest and strongest repair overall and within each group of cadaveric specimens. This was followed by the Morscher hook screw. Both the screw and hook repair were statistically significantly stronger and stiffer than the wire repair. There was no statistical difference between the screw and hook repairs regarding strength or stiffness. METHODS: Using the intact L1 vertebral body as a control for each cadaver, the three surgical techniques for pars repair could be evaluated. RESULTS: The screw repair provided 64% of the intact stiffness and 58% of the intact strength. The hook repair provided an average of 52% of the intact stiffness and 40% of the intact strength. The wire provided only 3.5% of the intact stiffness and 12% of the intact strength. CONCLUSIONS: The screw repair technique is the stiffest and strongest pars repair method. The wire technique restores the least stiffness and strength.

Aged↗

PubMed1994

Indications for pedicle fixation. Results of NASS/SRS faculty questionnaire. North American Spine Society and Scoliosis Research Society.

STUDY DESIGN: The faculty of the North American Spine Society and Scoliosis Research Society pedicle fixation workshop were questioned about their use of pedicle screw implants for fixation of the spine. OBJECTIVES: This study ascertained which faculty members used pedicle implants given specific clinical scenarios and analyzed the data for trends and consensus. SUMMARY OF BACKGROUND DATA: For the past 4 years, the North American Spine Society in conjunction with the Scoliosis Research Society has sponsored a course on pedicle fixation of the spine. During these courses, techniques of pedicle fixation have been discussed. The indications, however, for pedicle fixation have remained controversial, even among the course faculty. METHODS: A questionnaire was developed with 20 clinical scenarios, and the faculty were asked whether they would use pedicle implants as part of their surgical treatment. RESULTS: Thirty-eight of 45 (84%) questionnaires have been received and analyzed. For most scenarios, there was statistically significant consensus among the faculty that they would use a pedicle implant. There was statistically significant consensus that the faculty would not use pedicle implants for thoracic fractures or adolescent idiopathic scoliosis. DISCUSSION: This study is useful in assessing pedicle implant usage in our community but should not be used as a guide for their indications and contraindications.

Adolescent↗

PubMed1994

A comparative analysis of spondylolysis repair.

STUDY DESIGN: This retrospective study compared patient outcome after two surgical techniques for pars interarticularis repair: 1) buck screw fixation and 2) the modified Morscher-designed spondylolysis distraction hook. OBJECTIVES: To determine whether one technique was associated with higher radiographic, clinical, or implant failure. SUMMARY OF BACKGROUND DATA: Both techniques have been reported as giving good clinical results. METHODS: Twenty patients were included in this study. All patients had Type IIA spondylolytic defects with either a Grade 0 or Grade I spondylolisthesis. Nine patients were treated with the Morscher hook implant, and 11 patients were treated with the Buck technique. RESULTS: Radiographic follow-up of the Morscher implants demonstrated loosening in three and breakage in one. Radiographic analysis of the Buck technique demonstrated implant failure in one. Failure of healing occurred in four instances with the Morscher implant compared with two instances with the Buck technique. Clinical outcome was assessed using the modified Prolo score. The mean outcomes were 6.33 in the Morscher group and 6.09 in the Buck group. CONCLUSIONS: In these patients, the Morscher implant had a high failure rate. Furthermore, the clinical outcome in this group of patients was poor using either technique.

Adult↗

PubMed1994

A histologic study of soft-tissue reactions to spinal implants.

OBJECTIVES: The biologic reactions to orthopedic spinal implants were determined. METHODS: Biopsies of soft tissue immediately adjacent to spinal implants were done in 36 consecutive patients undergoing elective lumbar spinal hardware removal and was studied histologically. RESULTS: A fibrous tissue matrix was noted in all specimens. In 11 of 36 specimens, a discrete layer of cells with epithelial characteristics was noted on the surface immediately opposed to the metal implant. Results of immunohistochemical staining were negative using antibodies to markers, which suggests that these unique cell layers are probably of histiocytic origin. Black amorphous metallic debris was seen in nine of the specimens. In seven of these specimens, this material was associated with an inflammatory foreign-body reaction. Refractile non-biorefringent crystalline bodies were noted in five specimens. These crystalline deposits provoked a local foreign-body reaction in all cases. CONCLUSION: The role of soft-tissue inflammatory reactions in the production of clinical symptoms of pain is discussed.

Biopsy↗

PubMed1994

In vivo diurnal variation in intervertebral disc volume and morphology.

STUDY DESIGN: Three-dimensional reconstructions of MRI scans measured volume, height, and diameter of intervertebral discs. These measurements were made in vivo. OBJECTIVES: This study documented diurnal change in lumbar disc volume and morphology. The authors studied the pattern of this change over the disc levels that were examined and documented individual differences. SUMMARY OF BACKGROUND DATA: There is a diurnal pattern of standing heights. The majority of this diurnal height change can be accounted for by height loss within the intervertebral disc, which bulges radially with loading. These studies have been performed in vivo. METHODS: Eight normal males were studied using two protocols. In one, the volunteers were in the supine position for 6 hours before MRI scanning. In the other, volunteers spent 4 hours standing and 3 hours sitting before MRI scanning. Three-dimensional MRI scanning was carried out on the L3-4, L4-5, and L5-S1 discs. RESULTS: Volume height and AP diameter of the lumbar intervertebral discs decreased significantly after the protocol of a day's activity. The mean decrease in disc volume at the L3-4 level after standing was 21.1%. At the L4-5 level, it decreased a mean of 18.7%, whereas at the L5-S1 level, there was a 21.6% mean decrease. CONCLUSIONS: The mean simulated diurnal volume decrease in the lower three lumbar discs is 16.2%. Most of the diurnal loss in disc height is due to volume loss. The effect of radial bulging is minimal.

Adult↗

PubMed1993

A histologic study of lumbar pseudarthrosis.

Biopsy specimens were obtained from 35 consecutive patients undergoing pseudarthrosis repair after failed posterior spinal fusions. Biopsy specimens were obtained when possible from the fusion mass, from areas of motion, and from the lumbar facet remnant where identifiable. Tissue found between adjacent bony segments was noted to contain predominantly fibrous tissue often accompanied by signs of local fibrocartilaginous metaplasia. In addition, small fragments of impacted bone, sometimes seen to be undergoing active resorption, also were noted frequently in these areas. The bone adjacent to the areas of motion was sclerotic and poorly organized, containing a mixture of woven and lamellar bone. Interestingly, multiple microtrabecular fracture with appositional new bone formation was a frequently seen feature. All facet joint biopsies were noted to have evidence of degenerative disease. Both cartilage fissuring and significant chondrocyte cloning were noted. Subchondral bony sclerosis was also a consistent feature.

Biopsy↗

PubMed1993

Late infection of spinal instrumentation by hematogenous seeding.

Six cases of late spinal infection following instrumentation are described. In all cases, there was a delay of at least 10 months between surgery and the clinical development of sepsis. In 5 of the 6 cases, a distant focus of infection could be identified. Two patients had active intravenous drug usage, two patients were paraplegic with neurogenic bladders, and one patient had an episode of pyelonephritis secondary to renal calculi two months prior to presentation. In no instance was there any preceding breakdown of overlying skin. This previously unreported phenomenon is an extremely rare but major complication of spinal surgery.

Adolescent↗

PubMed1993

A biomechanical study of odontoid fractures and fracture fixation.

The purpose of this study was to measure the stability of the odontoid process after fracture and subsequent screw fixation. To accomplish this, we mechanically reproduced Type II and Type III odontoid fractures on isolated C2 vertebrae by varying the direction of load. These fractures were subsequently stabilized with a single 3.5 mm screw and retested for multidirectional stability and load to failure. Reduced and instrumented specimens were found to have a stiffness equivalent to one half of that of the unfractured odontoid. Load to failure was also slightly less than one half of the original fracture force (average 160 lb). Screw failure was by a cut-out mechanism in all Type III fractures and by bending of the screw in all Type III fractures. Our findings, in conjunction with the existing literature, strongly suggest that Type III fractures result from extension forces, whereas Type II fractures result from lateral or oblique loading forces. Single screw fixation of an odontoid fracture will provide stability equal to approximately one half that of the unfractured bone.

Aged↗

PubMed1993

The value of facet joint blocks in patient selection for lumbar fusion.

The purpose of this study was to ascertain the correlation between diagnostic facet blocks and treatment outcome, both surgical and nonsurgical. One hundred twenty-six patients who had previously undergone diagnostic facet injections were reviewed. Eighty-two had subsequently undergone lumbar arthrodesis. The rest were treated with a variety of nonoperative modalities. Statistical analysis of accumulated data failed to show any significant correlation between the results of facet blocks and outcome of operative arthrodesis. In addition, statistical analysis failed to show any significant correlation between the facet block results and the outcome of nonoperative treatment. The authors concluded that lumbar facet joint injections cannot be used to determine appropriate patient treatment because they are not predictive of either surgical of nonsurgical success.

Adult↗

PubMed1993

Anterior cervical plate fixation with the titanium hollow screw plate system.

Although anterior cervical plates provide excellent fixation for the anterior column, the potential risk for injury to the spinal cord or soft tissues involved with their use has been the reason they have not gained universal acceptance. Morscher introduced a system that attempts to prevent the migration and loosening of screws by using a cross-split screw head that can be locked into the plate. The secondary advantage of this system is that it eliminates the requirement for posterior cortex purchase and thereby decreases the risk for spinal cord injury. This article reports the authors' experience using the Morscher titanium hollow screw cervical plate system. Forty-two patients in the series underwent anterior cervical arthrodesis for degenerative disease or trauma. The average number of levels fused were two. The fusion rate was 100%. Significant hardware loosening occurred in two patients. There was no iatrogenic injury to the spinal cord or esophagus. In conclusion, the titanium hollow screw cervical plate provides immediate stable fixation with minimal complications. Its use should be considered in the surgical treatment of patients requiring multilevel anterior cervical arthrodesis.

Adult↗

PubMed1993

Complications associated with the technique of pedicle screw fixation. A selected survey of ABS members.

A limited survey analysis of 617 surgical cases in which pedicle screw implants were used was undertaken to ascertain the incidence and variety of associated complications. The different implant systems used included variable spinal plating (n = 249), Edwards (n = 143), and AO fixateur interne (n = 101). The most common intraoperative problem was unrecognized screw misplacement (5.2%). Fracturing of the pedicle during screw insertion and iatrogenic cerebrospinal fluid leak occurred in 4.2% of cases. The postoperative deep infection rate was 4.2%. Transient neuropraxia occurred in 2.4% of cases, and permanent nerve root injury occurred in 2.3% of cases. Previously unreported injury to nerve roots occurred late in the postoperative course in three cases. Screw breakage occurred in 2.9% of cases. All other complications had an incidence of less than 2%. The authors conclude that pedicle screw placement may be associated with significant intraoperative and postoperative complications. This information is of value to surgeons using pedicle implant systems as well as to their patients. Repeat surgery is associated with greater numbers of complications.

Bone Screws↗

PubMed1992

Intraosseous vertebral body pressures.

In an effort to determine the relationship between low-back pain and intraosseous hypertension, in vivo vertebral pressure measurements were performed on 19 patients. A cannulated screw was placed percutaneously into the middle of the vertebral body by a transpedicular route. Pressure measurements were recorded with the patient in various positions. Pressures were greatest in the sitting position, lowest in the prone position, and intermediate in the standing position. A correlation was found between intravertebral body pressure and patient position. Pressures were highest in the positions most commonly associated with low-back pain.

Back Pain↗

PubMed1992

Unilateral facet dislocation of the lumbosacral junction.

Fracture-dislocation of the lumbosacral junction is an extremely rare injury. The authors are aware of only 24 reported cases. Only seven of these were unilateral facet dislocations. In this report, the authors review their experience with four cases of unilateral facet dislocations at the lumbosacral junction. In one of these cases, there was a pre-existing spondylolysis at L5, and the patient sustained a concomitant sacral fracture. From their review, the authors recommend the use of open reduction with internal fixation and lumbosacral fusion as the treatment of choice for this injury.

Adolescent↗

PubMed1992

A new scale for the clinical assessment of spinal cord function.

The systems currently used for grading the severity of neurologic injuries have serious limitations. The authors have developed a neurologic grading system to assess spinal cord function. This is a new, functionally oriented scale which can be used at the bedside and requires no special tests other than those done in a routine clinical neurological examination. This scale includes assessment of motor and sensory function, rectal tone, and bladder control. A major advantage of this scale is that motor function is assessed on a functional rating system. To evaluate the usefulness of this scheme, patients who have been previously entered into a prospective study on the surgical treatment of burst fractures were re-evaluated. A significant number of patients under our new reclassification system were noted to have had significant improvement which had been overlooked using the Frankel Grade system. The authors conclude that their new spinal cord assessment technique has many advantages and suggest that it be used by spinal cord injury centers.

Anal Canal↗

PubMed1992

Indications for lumbar spine fusion in the adult.

More than 20,000 lumbar spine fusions are performed annually in the United States. Results of surgery unfortunately are inconsistent and may reflect unsatisfactory patient selection. Indications for lumbar arthrodesis may arise in degenerative disk disease, deformity, distal extension of previous arthrodesis, trauma, spondylolisthesis, and spinal stenosis (in association with diskectomy or decompression). There are several techniques in the assessment of potential candidates for low lumbar arthrodesis.

Age Factors↗