James G. Jarvis

Complications of rigid intramedullary rodding of femoral shaft fractures in children

BACKGROUND Intramedullary rodding of femoral shaft fractures has been frequently performed in adults, but until recently rarely in children. It was the purpose of this study to investigate the experience with this treatment method at a pediatric trauma center. METHODS From 1987 to 1998, 54 children were treated for traumatic femoral fractures with intramedullary rods at a major pediatric trauma center. The average age was 15 years 3 months, ranging between 11 years 4 months and 17 years 11 months. The average follow-up was 5 years 3 months, ranging from 20 months to 10 years 1 month. RESULTS All of the fractures occurred secondary to trauma and the most common anatomic fracture site was the femoral midshaft. Complications encountered included 8 instances of minor limb length discrepancy, 11 instances of discomfort because of rod prominence, 1 case of avascular necrosis of the femoral head, 2 instances of heterotopic ossification over the rod tip, 1 broken rod, and 3 cases that demonstrated decreased external rotation of the affected limb. One child developed osteomyelitis after intramedullary rodding for a fracture previously treated with external fixation. There were no cases of surgically induced nonunion or malunion and only one delayed union secondary to infection. CONCLUSION Results of this series demonstrate intramedullary rodding to be an effective treatment modality for femoral fractures in skeletally mature children. In children with open femoral physes, rigid rodding should be avoided because of the small but serious occurrence of avascular necrosis of the femoral head. Intramedullary rodding is not recommended in children initially treated with external fixation because of the increased risk of infection.

Efficacy of aprotinin in reducing blood loss in spinal fusion for idiopathic scoliosis.

Aprotinin is a proteinase inhibitor with antifibrinolytic properties that has found widespread application during cardiac surgical procedures due to its ability to decrease blood loss and transfusion requirements. Recently it has been used by orthopedic surgeons in hip replacement and other major surgeries except for scoliosis surgery, which is known to be associated with major blood loss. To evaluate the effect of aprotinin in reducing blood loss during spinal fusion surgery for idiopathic scoliosis, a double-blind randomized prospective clinical study was performed. Forty-three patients with idiopathic scoliosis underwent spinal fusion and instrumentation and were divided randomly into two groups. Fifteen patients received aprotinin, whereas 28 patients received placebo. The aprotinin group had less blood loss than the placebo group. The transfusion requirement was less in the aprotinin group than the placebo group. Although the difference was not significant statistically, the benefit of aprotinin in reducing blood loss in spinal surgery for idiopathic scoliosis was consistent.

Pathogenesis of soft-tissue contracture in club foot

We investigated the pathogenesis of soft-tissue contracture in club foot, using immunohistochemistry to study 41 biopsy specimens and 12 normal deltoid ligaments from cadavers. Five biopsy specimens were studied by electron microscopy (EM) to determine the presence of myofibroblasts. All 41 specimens of club foot stained positively for vimentin as against only one of the 12 control specimens. By contrast, there was no difference in staining for desmin or alpha-smooth muscle actin. EM showed some variability in the appearance of ligamentous cells. Most contained bundles of microfilaments in the cytoplasm and many had abundant pinocytotic vesicles, but no basal lamina or plasmalemmal attachment plaques. Cells of the medial ligamentous tissue in patients with club foot contain vimentin and others have myofibroblastic characteristics. Both features may contribute to recurrence after soft-tissue release.

Cerebral microembolization during pediatric scoliosis surgery: a transcranial doppler study.

The goal of this study was to identify cerebral microemboli during scoliosis surgery and their potential relationship with visual alterations. Transcranial Doppler identified high-intensity transient signals (HITS) during surgery in both middle cerebral arteries, and ophthalmologic examination assessed their potential effects on the visual system. Thirteen children (age 13–17 years) undergoing surgery for scoliosis or kyphosis with spine curvature >45° were studied. HITS were identified in 92%. Eleven patients had a total count of <15 HITS, but in the remaining two the count was unexpectedly high (63 and 265 HITS). Echocardiography in these two patients indicated the presence of an atrial right-to-left shunt. Uneventful preoperative and postoperative visual function was found in 11 patients. One patient had preoperative blindness and in another ophthalmologic complications developed not related to microembolization. Scoliosis surgery is frequently associated with low counts of cerebral microemboli. It appears that such low embolic counts have no effects on postoperative visual function as determined clinically. Some patients may show high rates of microemboli, which may be related to the presence of right-to-left cardiac shunts. The impact of these signals on brain function remains to be investigated.

Congenital kyphosis in myelomeningocele. The effect of cordotomy on bladder function.

To determine the effect of cordotomy on the function of the bladder during surgical correction of congenital kyphosis in myelomeningocele, we reviewed 13 patients who had this procedure between 1981 and 1996. The mean age of the patients at operation was 8.9 years (3.7 to 16) and the mean follow-up was 4.8 years (1.3 to 10.8). Bladder function before and after operation was assessed clinically and quantitatively by urodynamics. The mean preoperative kyphosis was 117 degrees (52 to 175) and decreased to 49 degrees (1 to 89) immediately after surgery. At the latest follow-up, a mean correction of 52% had been achieved. Only one patient showed deterioration in bladder function after operation. Eight out of the nine patients who had urodynamic assessment had improvement in bladder capacity and compliance, and five showed an increase in urethral pressure. One patient developed a spastic bladder and required subsequent surgical intervention. Cordotomy, at or below the level of the kyphosis, allows excellent correction of the structural deformity.

Adolescent Idiopathic Scoliosis. Correction of Vertebral Rotation with Use of Wisconsin Segmental Spinal Instrumentation

We retrospectively reviewed the results of use of Wisconsin segmental spinal instrumentation in twenty-four patients who had adolescent idiopathic scoliosis. Our purpose was to determine whether there had been any correction of the rotational component. The mean age at the time of the operation was thirteen years and eight months (range, eleven to seventeen years). Computerized tomography was used to measure the degree of vertebral rotation relative to the midline of the body and relative to the mid-sagittal plane in thirty curves that had been treated with instrumentation and in fifteen that had not. According to the criteria of King et al., five patients had a type-I curve; fourteen, a type-II curve; four, a type-III curve; and one, a type-V curve. The mean correction in the coronal plane was 23 degrees (43 per cent; range, 20 to 69 per cent) for the curves that had been treated with instrumentation and 15 degrees (35 per cent; range, 11 to 77 per cent) for those that had not. The mean derotation of the apical vertebra, in relation to the midline of the body, in twenty-two curves that had been treated with instrumentation and that had had a mean initial rotation of 26 degrees (range, 8 to 53 degrees) was 6 degrees (range, 1 to 29 degrees). For seven curves, with a mean initial rotation of 25 degrees (range, 21 to 35 degrees), rotation increased a mean of 3 degrees (range, 1 to 7 degrees) after instrumentation. The rotation of the apical vertebra did not change in one curve treated with instrumentation. Derotation was seen in twelve of the fifteen curves that had not been treated with instrumentation.

Congenital trigger thumb in children: electron microscopy and immunohistochemical analysis of the first annular pulley

Although numerous studies have been performed on congenital trigger thumb (CTT), the pathogenesis is still unknown. Cytocontractile proteins and myofibroblasts are present during soft-tissue contraction, and they may have a role in CTT. The aim of the study is to clarify the immunohistochemical and the electron microscopy characteristics of the first annular (A-1) pulley in CTT. The specimens from the A-1 pulleys were collected from 22 children with CTT. Electron microscopy was used to study the last five specimens. Immunohistochemistry staining demonstrated that all specimens stained positively for vimentin and for &agr;-smooth muscle actin, and stained negatively for desmin. Electron microscopy showed fibroblasts in collagenous matrix, which contain vimentin-like material and associated at the surface with elastin-like tubular matrix filaments and elastin fibers. In two specimens, a few cells showed markers of myofibroblastic differentiation. The presence of the cytocontractile proteins and myofibroblasts suggests proliferation of fibrous tissues during either the intrauterine or extrauterine phase of development and may account for the presence of congenital stenosis at the level of the A-1 pulley. We believe that CTT may be developmental; if the process started in the intrauterine phase it might present as a fixed flexion contracture and will show mature fibroblasts. If the process started in the extrauterine phase, it might present as triggering first and will show myofibroblastic changes, then with the maturation of the fibrous tissue, result in a fixed flexion contracture.

The long-term outcome of patients treated operatively and non-operatively for scoliosis deformity secondary to spina bifida

The purpose of this study was to evaluate the long-term outcome of adults with spina bifida cystica (SBC) who had been treated either operatively or non-operatively for scoliosis during childhood. We reviewed 45 patients with a SBC scoliosis (Cobb angle ≥ 50º) who had been treated at one of two childrens hospitals between 1991 and 2007. Of these, 34 (75.6%) had been treated operatively and 11 (24.4%) non-operatively. After a mean follow-up of 14.1 years (standard deviation (sd) 4.3) clinical, radiological and health-related quality of life (HRQOL) outcomes were evaluated using the Spina Bifida Spine Questionnaire (SBSQ) and the 36-Item Short Form Health Survey (SF-36). Although patients in the two groups were demographically similar, those who had undergone surgery had a larger mean Cobb angle (88.0º (sd 20.5; 50.0 to 122.0) ; : versus 65.7º (sd 22.0; 51.0 to 115.0); p < 0.01) and a larger mean clavicle-rib intersection difference (12.3 mm; (sd 8.5; 1 to 37); versus 4.1 mm, (sd 5.9; 0 to 16); p = 0.01) than those treated non-operatively. Both groups were statistically similar at follow-up with respect to walking capacity, neurological motor level, sitting balance and health-related quality of life (HRQOL) outcomes. Spinal fusion in SBC scoliosis corrects coronal deformity and stops progression of the curve but has no clear effect on HRQOL.

Diagnostic Accuracy of Neuromonitoring for Identification of New Neurologic Deficits in Pediatric Spinal Fusion Surgery.

BACKGROUND:Intraoperative neuromonitoring (IONM) modalities, transcranial motor-evoked potentials (TcMEPs), and somatosensory-evoked potentials (SSEPs) are accepted methods to identify impending spinal cord injury during spinal fusion surgery. Debate exists over sensitivity and specificity of these modalities. Our purpose was to measure the incidence of new neurologic deficits (NNDs) and estimate sensitivity and specificity of IONM modalities. METHODS:Institutional Ethics Board approval was obtained to review charts of patients younger than 22 years undergoing scoliosis surgery from 2007 to 2014 retrospectively. The definition of true-positive patients included two subgroups: (1) patients with an IONM alert, which did not resolve despite the interventions and had a NND postoperatively; or (2) patients with an IONM alert triggering interventions and the alert resolved with no NND postoperatively. Subgroup 2 of the definition is debatable; thus, we performed a multiple sensitivity analysis with three assumptions. Assumption 1: without interventions, all such patients would have experienced NNDs (assumption used in previous studies); Assumption 2: without intervention, half of these patients would have experienced NNDs; Assumption 3: without intervention, none of these of patients would have experienced NNDs. RESULTS:We included 296 patients. Patients with incomplete charts (n = 3), no IONM monitoring (n = 11), and inadequate baseline IONM (n = 7) were excluded. The incidence of NND was 3.7% (95% confidence interval, 2.1%–6.5%). Successful IONM in at least one modality was obtained in 275 patients (92.9%), of whom 268 (97.5%) and 259 (94.2%) had successful baseline TcMEP or SSEP signals, respectively. Fifty-one (17%) patients had IONM alerts, 41 were only TcMEP, 5 were only SSEP, and 5 were in both modalities. After interventions, 42 (82%) patients recovered, 41 had no NND (true-positive under Assumption (1), but one developed a NND (false-negative). Of the 9 patients with no alert recovery, 6 had a NND (true-positive) and 3 did not (false-positives). Of the remaining 224 patients with no alerts, 221 had no NND (true-negatives) and 3 did (false-negatives). Sensitivity was estimated to be 93.5%, 92.2%, and 46.7% for TcMEPs, combination (either TcMEPs or SSEPs), and SSEPs, respectively. Multiple sensitivity analysis demonstrated that sensitivity and specificity vary markedly with different assumptions. CONCLUSION:TcMEPs are more sensitive than SSEP at detecting an impending NND. IONM modalities are highly specific. Both sensitivity and specificity are impacted substantially by assumptions of the impact of interventions on alerts and NND. Properly designed, controlled, multicenter studies are required to establish diagnostic accuracy of IONM in scoliosis surgery.

Dega-Osteotomie bei Hüftgelenkdysplasie

ZusammenfassungOperationszielÜberdachung des Femurkopfes bei Hüftgelenkdysplasie.IndikationenDysplastisches Acetabulum bei Patienten mit neuromuskulären und nichtneuromuskulären Erkrankungen.Übergroßes, flaches Acetabulum.Fehlen einer lateralen und kranialen Überdachung.KontraindikationenY-Fuge geschlossen, Wachstum abgeschlossen.Stark verformter Femurkopf.OperationstechnikModifizierter Zugang nach Salter/Smith-Petersen. Freilegung und Teilung der Apophyse des Beckenkammes mit einem Messer. Freilegung der Darmbeinschaufel. Osteotomie der äußeren Wand des Iliums; sie wird vorsichtig mit Hilfe eines gebogenen meißels nach unten gebogen und in dieser Stellung durch Einsetzen von trikortikalen Beckenkammspänen gehalten. Eine Osteosynthese ist nicht notwendig. Becken-Bein-Gipsverband mit Einschluß des gegenseitigen Oberschenkels für sechs Wochen.ErgebnisseZwischen 1987 und 1997 wurden 26 Hüften von 23 Patienten operiert. Überwiegend handelte es sich um Kinder mit spastischen Paresen. Folgende zusätzliche Eingriffe wurden vorgenommen: Offene Reposition zehnmal, Femurosteotomie 18mal und Tenotomien sowie Muskelablösungen 15mal. Der Durchschnittswert des azetabulären Index verbesserte sich von 32° auf 22°, der durchschnittliche Wert des Kopfzentrum-Pfannenrand-Winkels von −25° auf 22° und der durchschnittliche Migrationsindex von 62% auf 69%. Als Komplikationen wurden beobachtet: eine erneute Subluxation, ein frühzeitiger Verschluß des Y-Knorpels, eine Fraktur des anderen Femur, einmal heterotope Ossifikationen und einmal eine Infektion der Harnwege.