John P. Lubicky

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 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.

Classification of congenitally fused cervical patterns in Klippel-Feil patients: epidemiology and role in the development of cervical spine-related symptoms.

Study Design. A retrospective cohort and series review. Objectives. To determine the role of cervical spine fusion patterns on the development of cervical spine-related symptoms (CSS) in patients with Klippel-Feil syndrome (KFS) and evaluate age- and time-dependent factors that may contribute to fused cervical patterns and the development of the CSS. Summary of Background Data. Although the “hallmark” of KFS is the presence of congenitally fused cervical vertebrae, the epidemiology and role of specific cervical fused patterns are limited. In addition, the incidence of symptoms and various age- and time-dependent factors that are directly attributed to the congenitally fused cervical segments in KFS patients is unknown. Methods. A radiographic and clinical review of 28 KFS patients at a single institution. Radiographically, Type I patients were defined as having a single congenitally fused cervical segment. Type II patients demonstrated multiple noncontiguous, congenitally fused segments, and Type III patients had multiple contiguous, congenitally fused cervical segments. Clinical records were reviewed for patient demographics, presence and type of symptoms, and clinical course. Results. Twelve males and 16 females were reviewed for clinical follow-up (mean, 8.5 years) and radiographic assessment (mean, 8.0 years). The mean age at presentation was 7.1 years; mean age of onset of CSS was 11.9 years. Clinically, 64% had no complaints referable to their cervical spine. Radiographically, 25%, 50%, and 25% were Type I, Type II, and Type III, respectively. At final clinical follow-up, 2 patients were myelopathic (Type II and Type III) and 2 were radiculopathic (Type II and Type III). Type III patients were largely asymptomatic but were associated with the highest risk in developing radiculopathy or myelopathy than Type I or Type II patients. Axial symptoms were predominantly associated with Type I patients. Myelopathic patients developed initial CSS earlier (meanage, 10.6 years) than patients with predominant axial (mean age, 13.0 years) or radiculopathic symptoms (mean age, 18.6 years) (P > 0.05). Patients with radiculopathy or myelopathy were diagnosed at a mean age of 17.9 years. Type I patients were predominantly females, while males were largely Type III. Surgery entailed 11% of patients, composed of 2 myelopathic patients (Type II and Type III) and 1 radiculopathic patient (Type II). Conclusions. In our review, 36% of KFS patients had CSS and the majority had axial symptoms. Axial neck symptoms were highly associated with Type I patients, whereas predominant radicular and myelopathic symptoms occurred in Type II and Type III patients. This classification system has promise for early detection for CSS. Activity modification should be stressed in KFS patients at high risk for neurologic compromise.

Long-term outcomes and life satisfaction of adults who had pediatric spinal cord injuries

OBJECTIVE To determine long-term outcomes and life satisfaction of adults who sustained pediatric spinal cord injury (SCI). DESIGN Structured interview of adults who were 25 years or older who had pediatric SCI. SETTING Community. PARTICIPANTS A convenience sample of 46 patients from a total of 81 patients who received care in an SCI program: 1 refused participation, 4 died, and 30 were lost to follow-up. MAIN OUTCOME MEASURES A structured questionnaire including physical, psychosocial, and medical information. The Craig Handicap Assessment and Reporting Technique and two measures of life satisfaction were also administered. RESULTS Participants were 25 to 34 years old, mean 27 years. Thirty-two had tetraplegia and 14 had paraplegia. Thirty-one were men. Mean years of education was 14. Fifty-four percent were employed, 48% lived independently, and 15% were married. Life satisfaction was associated with education, income, satisfaction with employment, and social/recreation opportunities, and was inversely associated with some medical complications. Life satisfaction was not significantly associated with level of injury, age at injury, or duration of injury. CONCLUSIONS Individuals who had pediatric SCI, much like adult-onset SCI, have the greatest opportunity for a satisfying adult life if rehabilitation emphasizes psychosocial factors such as education, employment, and long-term health management.

Variability of somatosensory cortical evoked potential monitoring during spinal surgery

The Intraoperatlve 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 Idlopathlc scollosis, spondylolisthesls, and pseudarthrosis have the smallest spontaneous variability and strongest amplitudes, while those with congenital, paralytic scollosis, stenosis, or tumor have very variable, weak SCEPs. Patients with neurologic disorders, particularly cerebral palsy, myelomeningocele, Frledrelchs 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.

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.

Community-associated methicillin-resistant Staphylococcus aureus in acute musculoskeletal infection in children: a game changer.

Background Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a virulent pathogen responsible for an increasing number of invasive musculoskeletal infections in healthy children. The purpose of this study is to characterize the presentation, clinical course, treatment, complications, and long-term morbidity of CA-MRSA musculoskeletal infection in children. Methods A retrospective study of children with CA-MRSA musculoskeletal infections from 2 institutions was conducted. Results The study group included 27 patients. Clinical presentation involved an extremity in 23 of 27 patients. Twelve patients required admission to the intensive care unit. Four of these patients developed acute multisystem failure. Magnetic resonance imaging was obtained in 21 patients and was diagnostic in all. Seven patients developed deep venous thrombosis and septic pulmonary emboli. All patients required surgical intervention, and 16 of 27 required multiple debridements. Conclusions CA-MRSA is limb and life threatening. Prompt recognition and treatment are critical. Aggressive surgical drainage/debridement in addition to long-term antibiotics is required. There is significant potential for long-term morbidity despite aggressive management. Level of Evidence Level IV, retrospective case series.

Radiographic assessment of segmental motion at the atlantoaxial junction in the Klippel-Feil patient

Study Design. A retrospective review of 33 consecutive Klippel-Feil syndrome (KFS) patients at a single institution. Objectives. To assess in KFS patients the presence and degree of radiographic segmental motion at the atlantoaxial junction, factors contributing to such motion, and associated clinical manifestations. Summary of Background Data. Studies suggest that abnormal segmentation in KFS patients may result in cervical hypermobility, increasing the risk of developing neurologic compromise and the need for surgical intervention. The use of the anterior and posterior atlantodens interval (AADI/PADI) has gained interest as a method for assessing atlantoaxial instability and for space available for the cord. Although helpful for identifying instability after trauma, these measurements are not understood in KFS patients. In addition, the effects of the fusion process associated with KFS on atlantoaxial motion and associated clinical findings have not been properly addressed. Methods. Radiographs were analyzed for the presence of occipitalization, number/location of congenitally fused segments, and the AADI and PADI. Results. There were 15 males and 18 females (mean age, 13.9 years). Occipitalization occurred in 48.5% of patients. A fused C2–C3 segment was noted in 72.7% of cases. More motion with respect to AADI was evident on O–C1 and C2–C3 fusion only patients, which were all asymptomatic. Overall, 24.2% of patients were symptomatic. Mean AADI and PADI difference was 2.0 mm (symptomatic: mean, 1.5 mm; asymptomatic: mean, 2.1 mm) and −1.7 mm (symptomatic: mean, −1.0 mm; asymptomatic: mean, −2.0 mm), respectively (P > 0.05). Conclusions. Hypermobility of the atlantoaxial junction, as indicated by increased AADI on flexion-extension radiographs, is not necessarily associated with an increased risk for the development of symptoms or neurologic signs in the KFS patient. Occipitalization plays an integral role in the degree of motion at the atlantoaxial region. Greatest AADI values were in patients with occipitalization and a fused C2–C3 segment. The presence of symptoms was not related to the degree of AADI change. Evaluation of the PADI provides additional information for identifying patients at risk for developing symptoms. Nonetheless, KFS patients remain largely asymptomatic.

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.

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.