Kyphectomy and segmental spinal instrumentation in young children with myelomeningocele kyphosis

For children with myelomeningocele kyphosis, the ideal timing for spinal correction or the correct stabilization technique for preventing the recurrence of deformity are controversial issues. From 1988 to 1992, vertebral kyphectomy and long segment spinal fixation with a special lower-end contouring around the anterior aspect of the sacrum through the sacral foramina (the modified Gillespie's technique) were carried out on six young children with ages ranging from three years and four months to five years and 11 months (average, five years). The indications for surgery were recurrent skin breakdown and/or increasing functional deficits due to curve progression. A mean preoperative kyphosis of 126.3 degrees was reduced to 21.8 degrees postoperatively. There was one case of pseudarthrosis seen at the osteotomy site which was treated with anterior interbody grafting. With a mean follow-up period of 35 months (range, 10-48 months), all patients showed good maintenance of correction and no implant failure. The average loss of correction was 2.7 degrees. We believe that in these young, severely handicapped children, long segment fixation using the modified Gillespie's technique with full or partial segment fusion allows a quick resumption of upright activities, achieves satisfactory correction of kyphosis and minimizes the risk of recurrent deformity.

Spinal deformity in Charcot-Marie-Tooth disease

STUDY DESIGN

This retrospective study reviewed 100 children with clinically and electrodiagnostically proven Charcot-Marie-Tooth disease (CMTD).

OBJECTIVE

To determine the incidence of spinal deformity in children with CMTD.

SUMMARY OF BACKGROUND DATA

A 10% incidence of kyphoscoliosis has been reported.

METHODS

All charts and electrodiagnostic studies were reviewed to confirm that CMTD diagnostic criteria were met. Existing radiographs on 89 children were available. Cobb angles were measured and deformity was defined as scoliosis > or = 10 degrees and kyphosis > 40 degrees.

RESULTS

Thirty-seven of 89 CMTD children had spinal deformity. There was scoliosis in 20, kyphoscoliosis in 14, and kyphosis in 3. In children with radiographs taken at maturity, 50% had deformity. The most common scoliotic pattern was a thoracic curve with convexity in either direction. Spinal deformity is more likely in female and Type I patients.

CONCLUSIONS

This study found an incidence of 37%-50% spinal deformity in children with CMTD, with female and Type I patients at greatest risk. However, the deformity rarely required treatment.

Hip abnormalities in children with Charcot-Marie-Tooth disease

Hip dysplasia was recently observed in association with Charcot-Marie-Tooth disease (CMT). We retrospectively reviewed available radiographs of 74 of 100 children with clinically and electrodiagnostically proven CMT and noted six cases of hip dysplasia. Minor hip abnormalities, most commonly increased neck shaft angles, were noted in 21 other patients. Type I usually causes more weakness and had more hip dysplasia than type II. A female predominance was noted but may have resulted from sampling of more immature radiographs in males. Most dysplasia was asymptomatic and was detected only on screening radiographs.

Prognosticating factors in acetabular development following reduction of developmental dysplasia of the hip

A number of predictors that may influence acetabular development after reduction were studied in 75 hips with developmental dysplasia of the hip (DDH). Seventy-nine percent of the hips had satisfactory results of Severin group I or II, and 21% had unsatisfactory results. The best predictor of success in a unilateral case is the center-head distance discrepancy (CHDD) measurement at 1 year follow-up. Ninety-six percent of hips with a CHDD of < or = 6% had satisfactory results, whereas 78% with a CHDD > 6% had unsatisfactory results. This study also confirms that age at reduction and significant improvement in the acetabular index in the first year after reduction are important predictors.

Further delineation of spondylo-meta-epiphyseal dysplasia, short limb-abnormal calcification type, with emphasis on diagnostic features

Further delineation of a generalized bone dysplasia which we call spondylo-meta-epiphyseal dysplasia, short limb-abnormal calcification type is presented. This dwarfing condition has several serious complications, with the most common cause of death being spinal cord damage secondary to atlantoaxial instability. It is a heritable condition with an autosomal recessive mode of transmission. Radiologic diagnostic criteria are developed on the basis of studies in 8 patients with the oldest being between 4 and 5 years old. The condition is clinically and radiographically apparent neonatally or in early infancy, and it is probable that all or almost all affected individuals will come to medical attention in the age range screened by this study.

Toxic shock syndrome in patients with external fixators

Toxic shock syndrome (TSS), first described by Todd et al. in 1978, can be a life-threatening entity. Familiarity with the pathogenesis and clinical presentation of TSS may help achieve early diagnosis and prompt appropriate intervention. TSS is not a septicemia, but a toxemia. The most extensively described pathogenesis involves a focus of specific Staphylococcus aureus strains capable of producing an exotoxin (TSST-1). We report two patients who developed TSS while in external fixators and describe their initial symptoms, management, and subsequent problems. This report will serve to alert pediatric orthopaedic surgeons to this entity and enable them to recognize its rather precipitous presentation and initiate appropriate treatment.

The Luque trolley revisited. Review of nine cases requiring revision

This study is a retrospective review of nine patients who underwent Luque instrumentation without fusion from 1982-1984. Average age at surgery was 9 years. Average preoperative curve was 51 degrees (30 degrees-70 degrees). All nine patients have had at least one revision. All of the revisions were technically difficult secondary to extensive fibrosis and weakened laminar bone. Spontaneous fusion was documented in all nine patients, limiting further correction. Final follow-up curves averaged 51 degrees (25 degrees-90 degrees). Average gain in spinal height was 5.8 cm (2.3 in) but only a small portion was derived from the instrumented levels. Segmental spinal instrumentation without fusion in immature patients was not effective in control of spinal deformity, nor did it allow anticipated growth under the instrumented regions.

Pseudoaneurysm after foot surgery

Pseudoaneurysm (PA) is recognized as a rare complication after pediatric foot surgery. We identified the incidence, pertinent clinical features, and response to surgical intervention in PA as a complication of foot surgery. Four PAs were identified after 2,756 foot operations, an overall incidence of 0.14%. These patients typically had symptoms between 2 and 3 months after index operation with an enlarging, pulsatile, compressible mass in the plantar medial aspect of the foot. Arteriography was helpful in planning surgical intervention. Operative treatment consisted of ligation and excision of PA in all patients. Final outcome of foot deformity surgery was not compromised.

Somatosensory cortical evoked potential changes after deformity correction

The somatosensory cortical evoked potentials recorded during posterior spine fusion and instrumentation for 99 consecutive patients with idiopathic scoliosis, 18 years of age or younger, were retrospectively reviewed. The potentials were recorded from scalp electrodes while synchronously stimulating both tibial nerves near the ankles. Signal changes observed during consecutive 30-minute time intervals after deformity correction were analyzed. No changes in neurologic status were observed postoperatively. Latency values tended to remain constant on average. A small, but statistically significant, decrease in the first two interpeak amplitudes was observed during the first 30-minute interval after deformity correction. The first interpeak amplitude recovered, while the second remained statistically significantly decreased. No patient had a decrease of greater than 50% in both of the first two amplitudes, which persisted throughout the 60-minute interval immediately after deformity correction. This study demonstrated a tendency for somatosensory cortical evoked potential interpeak amplitudes to decrease during the first 30 minutes after deformity correction. There was a great deal of individual variation, including amplitude increases in many patients. There was no evidence supporting an association between dramatic, sustained amplitude decreases and uncomplicated deformity correction. The value of thoroughly evaluating somatosensory cortical evoked potential signal trends while making intraoperative decisions is emphasized.

Crankshaft phenomenon in congenital scoliosis: a preliminary report

To determine whether or not the crankshaft phenomenon occurs after spinal fusion in patients with congenital scoliosis, we reviewed 23 curves in 21 patients who were operated on before age 10 years. Operative procedures consisted of various kinds of posterior fusions as well as anterior and posterior hemiepiphyseodeses. Seven of the 23 curves progressed greater than or equal to 10 degrees during the course of follow-up, and six of the seven demonstrated increased rotation and were believed to demonstrate the crankshaft phenomenon. No spines rotated without curve progression. The only statistically predictive factor was length of follow-up. No curve that underwent anterior and posterior hemiepiphyseodeses demonstrated the crankshaft phenomenon. Although the crankshaft phenomenon can occur in young patients operatively treated for congenital scoliosis, apparently it can be prevented by anterior fusion.

Variability of somatosensory cortical evoked potential monitoring during spinal surgery

The intraoperative variability of somatosensory cortical evoked potentials (SCEPs) has been measured for 320 consecutive spinal surgeries and found to be a function of patient diagnosis, neuromuscular status, age, and procedural factors. In many cases, it is likely that this variability severely limits the reliability and usefulness of spinal cord monitoring in detecting early cord compromise. Patients with idiopathic scoliosis, spondylolisthesis, and pseudarthrosis have the smallest spontaneous variability and strongest amplitudes, while those with congenital, paralytic scoliosis, stenosis, or tumor have very variable, weak SCEPs. Patients with neurologic disorders, particularly cerebral palsy, myelomeningocele, Friedreich's ataxia, and peripheral deficits, also have high variability and weak amplitudes. A monitoring quality scoring system is proposed that may be useful during surgery in judging how well the SCEPs can discern surgically related changes in cord function from background variations.

Early clinical experience with the Syracuse I-Plate: an anterior spinal fixation device

Sixteen patients were treated with a new anterior internal fixation device after thoracolumbar or lumbar decompression, and fusion with bone grafting. Ten patients had acute burst fractures, four had metastatic tumors, and two had old, healed fractures with deformity. In the acute fracture group, eight patients had neurologic deficits and seven patients experienced improvement. Six patients had lesions of the conus medullaris, all of which improved. The four patients with metastatic tumors underwent surgery for back and leg pain and all gained significant relief. Two patients had correction of old fracture deformity with satisfactory outcome. Complications were minimal. The new anterior stabilization device provided early stability, allowed early patient mobilization, was easy to insert, and has a low profile. Late collapse, non-union, and kyphotic deformity have not been noted thusfar.

Reduction of the intracanal fragment in experimental burst fractures

An experimental investigation was carried out to create burst fractures and to evaluate the mechanisms and degree of reduction of the intracanal fragment with posterior instrumentation techniques in multisegmental human cadaver specimens. Reduction of the spinal fragment through kyphosis correction and distraction was evaluated using CT imaging. With kyphosis correction alone there was no decrease in canal compromise; in some cases there was a slight increase in canal compromise. Distraction, whether applied before or after kyphosis correction was the effective mechanism in reducing the fracture fragment. Kyphosis correction applied after distraction did not reduce the fragment further. Posterior devices that are used to treat burst fractures of the thoracolumbar spine with intracanal fragments should provide some form of distraction.

Ultrasonography for urinary tract evaluation in patients with congenital spine anomalies

Outpatient pediatric orthopedic records were reviewed retrospectively in an attempt to identify all patients with congenital spine and urinary tract anomalies. All patients with a positive intravenous pyelogram (IVP) were asked to return for ultrasonographic evaluation. Urinary tract abnormalities were identified in seven (26%) of the 27 patients with documented IVPs. An additional patient was later added to the series, making a total of seven patients who returned for an ultrasonogram, which was then compared with the IVP. Observations and a review of the literature suggest that ultrasonography combined with urinalysis and serum creatinine is the screening protocol of choice in this patient population.

The natural history of spondylolysis and spondylolisthesis

We performed a prospective roentgenographic study to determine the incidence of spondylolysis, spondylolisthesis, or both, in 500 unselected first-grade children from 1955 through 1957. The families of the children with spondylolysis were followed in a similar manner. The incidence of spondylolysis at the age of six years was 4.4 per cent and increased to 6 per cent in adulthood. The degree of spondylolisthesis was as much as 28 per cent, and progression of the olisthesis was unusual. The data support the hypothesis that the spondylolytic defect is the result of a defect in the cartilaginous anlage of a vertebra. There is a hereditary pre-disposition to the defect and a strong association with spina bifida occulta. Progression of a slip was unlikely after adolescence and the slip was never symptomatic in the population that we studied.

The anatomy of a congenitally short limb with clubfoot and ectrodactyly

Previous studies have shown an association between an abnormal arterial pattern and bony malformations of the human lower limb. We have dissected and performed arteriography on a congenitally short limb with ectrodactyly in order to examine the relationship between arterial pattern and bony anomalies in another type of deformity. The bony anomalies were a combination of short femur, tibia and fibula, clubfoot with tarsal synostoses, metatarsal absence, ectrodactyly, and a bifid hallux. The arterial pattern was characterized by deficiency of the anterior tibial artery and absence of the plantar arch. Major muscular anomalies were noted in the foot only; the muscles of the missing toe were absent and any muscles that normally cross the midventral line were either missing or failed to cross the midline. The superficial peroneal nerve failed to enter the dorsum of the foot and its sensory distribution was assumed by an extra branch of the sural nerve. The most severe abnormalities of the bones, muscles, arteries, and nerves occurred near the midventral line of the foot. We hypothesize that the abnormal arterial pattern put the limb at risk of teratogenic damage by reducing the number of collateral blood supply routes. We suggest that some event, such as extravasation of blood or embolization, compromised the blood flow in the remaining blood vessels and that this event resulted in both a general shortening of the limb and the specific defects observed in the foot. We interpret the anatomy to be consistent with the vascular teratogenic event occurring near the midline of the foot during the fifth week of embryonic development.

The value of computed tomography in thoracolumbar fractures. An analysis of one hundred consecutive cases and a new classification

We studied 100 consecutive patients with potentially unstable fractures and fracture-dislocations by multiplane computed tomography. The mechanism of failure of the middle osteoligamentous complex of the spine (posterior longitudinal ligament, posterior part of the vertebral body, and posterior annulus fibrosus) was determined by three-dimensional analysis. Three modes of middle-column failure were used to classify the injuries: axial compression (seventy-three patients), axial distraction (fifteen patients), and translation within the transverse plane (twelve patients). Fifty of eighty-six patients who were evaluated in the acute phase of injury underwent operative stabilization, and the mechanism of middle-column disruption determined the type of instrumentation that was used. Compression and distraction injuries of the middle complex could be appropriately treated by Harrington distraction and compression instrumentation, respectively. However, in translational injuries (torn posterior longitudinal ligament) routine Harrington instrumentation was contraindicated due to the risk of overdistraction. Translational injuries were associated with the greatest degree of instability and often had complete ligament discontinuity at the level of the affected vertebrae. Patients with a translational injury had the most severe neural deficits (six of eleven patients studied acutely having a complete spinal cord lesion). Translational injuries of the middle column were treated by segmental spinal instrumentation to provide strong fixation with minimum risk of neural sequelae from passing sublaminar wires. Moreover, postoperative use of a cast over insensate skin was not required. Computed tomography was more sensitive than any other modality in the diagnosis of disruption of the posterior elements in unstable burst fractures, and computer-reconstructed sagittal images were accurate in evaluating the nature of facet-joint failure in distraction injuries. Computed tomography with metrizamide proved superior to either conventional tomography or myelography alone in localizing the site of neural canal compromise in acute thoracolumbar injuries. The mode of failure of the middle osteoligamentous complex as visualized by computed tomography determined the pattern of spinal injury, the severity of the neural deficit, the degree of instability, and the type of instrumentation required.