Titanium elastic nailing of fractures of the femur in children. Predictors of complications and poor outcome.

Between 1996 and 2003 six institutions in the United States and France contributed a consecutive series of 234 fractures of the femur in 229 children which were treated by titanium elastic nailing. Minor or major complications occurred in 80 fractures. Full information was available concerning 230 fractures, of which the outcome was excellent in 150 (65%), satisfactory in 57 (25%), and poor in 23 (10%). Poor outcomes were due to leg-length discrepancy in five fractures, unacceptable angulation in 17, and failure of fixation in one. There was a statistically significant relationship (p = 0.003) between age and outcome, and the odds ratio for poor outcome was 3.86 for children aged 11 years and older compared with those below this age. The difference between the weight of children with a poor outcome and those with an excellent or satisfactory outcome was statistically significant (54 kg vs 39 kg; p = 0.003). A poor outcome was five times more likely in children who weighed more than 49 kg.

Altered fibular growth patterns after tibiofibular synostosis in children.

BACKGROUND: Iatrogenic synostosis of the tibia and fibula following an operation on the leg in a child has been reported rarely in the literature, and the effects of this complication on future growth, alignment, and function are not known. This is a retrospective case series, from one institution, of crossunions of the distal parts of the tibia and fibula complicating operations on the leg in children. The purpose is to alert surgeons to this possible complication. METHODS: The senior author identified eight cases of iatrogenic tibiofibular synostosis seen in children since 1985. The patients had various diagnoses and were from the practices of four pediatric orthopaedic surgeons. Synostosis developed in six patients after osteotomies of the distal parts of the tibia and fibula, in one after internal fixation of distal tibial and fibular metaphyseal fractures through a single incision, and in one after posterior transfer of the anterior tibialis tendon through the interosseous membrane combined with peroneus brevis transfer to the calcaneus. Medical records were reviewed, and preoperative and follow-up radiographs were analyzed for changes in the relative positions of the proximal and distal tibial and fibular physes and in the alignment of the ankle. RESULTS: Five patients were symptomatic after crossunion; they presented with prominence of the proximal part of the fibula, ankle deformity, or ankle pain. Three patients were asymptomatic, and a synostosis was identified on routine follow-up radiographs. Intraoperative technical errors caused two of the crossunions; the cause of the others was unknown. Following tibiofibular synostosis, growth disturbances were noted radiographically in every patient. The normal growth pattern of distal migration of the fibula relative to the tibia was reversed, resulting in a decreased distance between the proximal physes of the tibia and fibula as well as proximal migration of the distal fibular physis relative to the distal part of the tibia. Shortening of the lateral malleolus led to greater valgus alignment of the ankle. CONCLUSIONS: Tibiofibular synostosis can complicate an operation on the leg in a child. After crossunion, the normal distal movement of the fibula relative to the tibia is disrupted, resulting in shortening of the lateral malleolus and ankle valgus as well as prominence of the fibular head at the knee. The synostosis also interferes with the normal motion that occurs between the tibia and fibula with weight-bearing, potentially leading to ankle pain.

Scoliosis in children with anterior chest wall deformities.

An association between anterior chest wall deformities and scoliosis is described in the literature but is poorly defined. It appears that only approximately 4% to 5% of patients with severe anterior chest wall deformities have scoliosis of sufficient magnitude to warrant evaluation and observation by a spinal deformity physician. The relationship between anterior chest wall deformity and scoliosis is most clear in patients with Marfan syndrome. Marfan patients with scoliosis are at high risk for progression of deformity to unacceptable levels and have historically not responded well to brace therapy. The causes of anterior chest wall deformity and scoliosis remain unclear, although unbalanced cartilage growth has been proposed as a potential cause of both. Some have proposed that chest wall deformity may result in asymmetric spinal forces and subsequent scoliosis secondary to altered spinal growth. Because of the association between pectus deformities and scoliosis, patients with anterior chest wall deformities should be carefully examined for signs of scoliosis and have screening radiographs if indicated. Young patients in particular should be referred to a spinal deformity physician, because it is clear that patients who present with spinal deformity prior to age 5 years are the ones at risk for adverse cardiopulmonary sequelae related to spinal deformity. Most children with scoliosis and anterior chest wall deformities need only observation of the scoliosis. In more severe cases, the management of spinal deformity traditionally involves the use of bracing to attempt to control curves of lesser magnitude and surgical management for unacceptable deformities or curves of magnitudes too great for brace treatment. There are no studies that specifically address the use of these methods in patients with both anterior chest wall deformities and scoliosis. The management of scoliosis in patients with anterior chest wall deformities follows treatment principles outlined for idiopathic scoliosis patients.

Pre- and postoperative three-dimensional computed tomography analysis of triple innominate osteotomy for hip dysplasia.

Traditional methods of analysis and surgical techniques for hip dysplasia concentrate on frontal-plane analysis of the hip. More recent studies on imaging and operative correction of hip dysplasia recommend three-dimensional (3D) analysis, and some have mentioned but not emphasized the importance of transverse-plane acetabular anatomy (anteversion/retroversion). In this study we found that failure to analyze and understand transverse-plane acetabular anatomy can contribute to complications after triple innominate osteotomy (TIO). A subset of seven patients (eight hips) who were treated with TIO for deficient acetabular coverage resulting from hip dysplasia or Legg-Calvé-Perthes disease had both pre- and postoperative 3D computed tomography (CT) studies. Most of the postoperative studies were obtained to analyze complications (external limb rotation, nonunion). Analysis of the 3D CT studies showed a change in the position of the acetabular fragment after osteotomy into greater adduction, anterior rotation (extension), and external rotation, improving femoral head coverage. All of the hips had increased external rotation of the acetabulum after TIO. Excessive external rotation (>10 degrees) was noted in five hips, and these included two hips with pubic osteotomy nonunion, two with ischial nonunion, and one with marked external rotation of the lower limb. External rotation of the acetabular fragment during redirectional pelvic osteotomy can result in (a) excessive external rotation of the lower limb, (b) decreased posterior coverage, (c) increased gaps at the pubic and/or ischial osteotomy sites with resultant higher rates of nonunion, and (d) lateralization of the joint center. The surgical technique for TIO should be designed to avoid excessive external rotation of the acetabular fragment.

Early surgical correction of residual hip dysplasia: the San Diego Children's Hospital approach.

Studies of the etiology of premature osteoarthritis of the hip show that the most common cause is residual childhood hip dysplasia. Hip dysplasia is often asymptomatic in childhood, making detection difficult and creating complex treatment decisions (major surgery in the asymptomatic child). Symptoms do not develop typically until the teenage or early adult years, and surgical correction at this age is often incomplete and complicated. In contrast, if the dysplasia is recognized early, surgical correction can be performed using simpler osteotomies with more predictable results. Our experience with children, adolescents and adults with residual hip dysplasia has led us to adopt a philosophy of early surgical correction which seeks to normalize hip joint morphology by age 5 or 6 years. The reasoning, methods and early results of this approach are reviewed in this paper.

Anteversion of the acetabulum in developmental dysplasia of the hip: analysis with computed tomography.

Acetabular anteversion was measured by using two-dimensional (2-D) computed tomography (CT) scans in 39 dysplastic and 27 normal hips (patient age range, 3-33 years), and averaged 19.7 degrees in the dysplastic hips and 18.1 degrees in the normal hips. There was no statistically significant difference between the two groups, with a wide range of acetabular anteversion values noted in both groups (8-32 degrees ). Although acetabular anteversion may be increased in some patients with developmental dysplasia of the hip (DDH), it is not a universal finding. We believe that assessment and understanding of acetabular anteversion is needed before performing corrective osteotomies for hip dysplasia to optimize results and avoid the complications of acetabular retroversion.

Comparative biomechanical analysis of supracondylar femur fracture fixation: locked intramedullary nail versus 95-degree angled plate.

OBJECTIVES: To compare the initial stability of the genucephalic (GSH) intramedullary nail and the 95-degree condylar compression screw and side plate (DCS) for distal femur fractures. DESIGN: Human cadaveric biomechanical study. PARTICIPANTS: Twelve matched pairs of fresh frozen human cadaveric femurs. INTERVENTION: Genucephalic intramedullary nail device (Smith and Nephew Richards, Memphis, TN, U.S.A.) and the 95-degree DCS device (Synthes USA, Paoli, PA, U.S.A.) were compared. Grouped or dispersed screw constructs were tested for each fracture fixation system with progressively more severe simulated fracture patterns. MAIN OUTCOME MEASUREMENT: Axial and torsional stiffness values. RESULTS: The DCS plate with the dispersed screw configuration had the greatest torsional stiffness (p < 0.0011). The GSH nail with the grouped screw configuration absorbed more energy (work) during axial loading compared with the plate constructs (p < 0.0007). There were no significant differences in axial or torsional stiffness within treatment groups for fracture patterns of increasing severity. CONCLUSIONS: Based on the authors' results, the selection of a GSH nail or a DCS plate should not be determined by the severity of the fracture. If a DCS plate construct is selected, the authors recommend a dispersed screw configuration, including the most proximal hole in the plate, to provide superior stiffness in torsional loading and equal stiffness in axial loading when compared with the GSH nail constructs. If a GSH nail is selected, the authors recommend a grouped screw configuration, which absorbed more energy during axial loading compared with the DCS plate constructs and the nail with the dispersed screw configuration.

Skin surface pressure beneath an above-the-knee cast: plaster casts compared with fiberglass casts.

Complications related to immobilization in a cast after an injury or an operation may be related to the materials used for the cast or to the techniques of application, or to both. To evaluate the widely held clinical opinion that the use of a fiberglass cast is dangerous and inappropriate when subsequent swelling of the extremity is anticipated, we studied the skin surface pressures that were generated beneath above-the-knee casts made with different materials and applied with different techniques. A prosthetic model of the lower extremity was designed with an expandable calf compartment to simulate swelling after an injury or an operation. With use of this model, we measured the skin surface pressure beneath a plaster-of-Paris cast, a fiberglass cast that had been applied with a standard technique, and a fiberglass cast that had been applied with a stretch-relax technique. The highest mean skin surface pressure after application of the cast (p < 0.001) and after simulated swelling of the limb (p = 0.04) was generated by the fiberglass cast that had been applied with a standard technique. The lowest mean skin surface pressure after application of the cast (p = 0.006), simulated swelling of the limb (p < 0.001), and all subsequent steps of the experimental protocol (p < 0.001) was generated by the fiberglass cast that had been applied with the stretch-relax technique. The mean skin surface pressure generated by the plaster cast and by the fiberglass cast applied with the standard technique did not return to the value before application of the cast until anterior and posterior longitudinal cuts had been made in the cast and the cast had been spread at those cuts. When the fiber-glass cast had been applied with the stretch-relax technique, the mean pressure returned to the baseline value after only an anterior longitudinal cut and spreading at that cut. The principal pitfall of the use of a fiberglass cast is related to the technique of application. When the fiberglass cast had been applied with the standard technique, it generated a mean skin surface pressure that was higher than that associated with the plaster cast and it accommodated simulated swelling poorly. When the fiberglass cast had been properly applied, with the stretch-relax technique, it generated a mean skin surface pressure that was significantly lower (p = 0.006) than that associated with the plaster cast and it better accommodated simulated swelling without the need to sacrifice the structural integrity of the cast.

Modular tibial augmentations in total knee arthroplasty.

Proximal tibial bony deficiencies are not uncommon in primary and revision total knee arthroplasty. Modular tibial augmentations were introduced to address these deficiencies. Alterations in strain distribution as a result of medial wedge and block augmentations were evaluated for a modular total knee arthroplasty system in 6 fresh frozen anatomic specimen tibias. Full-field strain patterns were examined using photoelastic coating methods, and high strain regions were evaluated using strain gage rosette techniques. The total knee arthroplasty installations were tested in static physiologic axial and torsional load configurations. The relative effects of sequential wedge and block augmentations compared with the nonaugmented case were statistically analyzed. There were no overall statistical differences in the 3 treatments in terms of maximal (principal) strains. A secondary analysis that evaluated specific location and load pattern combinations established several minor statistical differences along with insights into the manner in which each construct loads the proximal tibia. Although metal wedge augmentation commonly is used, block augmentation seems to be an appropriate alternative from a strain distribution standpoint in cases in which the block geometry better approximates the bony defect.

Is computed tomography useful after simple posterior hip dislocation?

Recent articles and textbooks of orthopaedic traumatology recommend routine computed tomography (CT) scans after successful reduction of simple posterior hip dislocations. This is based on the belief that CT, even in cases with concentric reductions, may identify fractures or intraarticular loose bodies not apparent on standard radiographs. This study was conducted to assess the usefulness of CT after concentric reduction of simple posterior hip dislocations. The hospital database was searched for all traumatic hip dislocations in the past 4 years. Charts and radiographs were reviewed, and only patients with simple posterior hip dislocations (no acetabular or femoral head fractures) and a concentric reduction identified on plain radiographs were included. Twenty-three patients who met these criteria and had subsequent CT scans to evaluate the hip joint were identified. CT scans confirmed the concentric reduction in all patients. Three small occult fractures were identified, and no occult intraarticular loose bodies were found. CT findings did not alter the treatment plan for any of the patients studied. In this small group of patients, CT scanning was not useful after concentric reduction by plain radiography of simple posterior hip dislocations.

Lumbar intervertebral disc transfer. A canine study.

STUDY DESIGN: Degenerative lumbar disc disease has been implicated as a cause of low back pain. Current treatment options for low back pain involve nonphysiologic fusion of the involved segments and have variable success rates. This is an experimental study of lumbar intervertebral disc transplantation using a canine surgical model. OBJECTIVES: This study evaluated the feasibility of lumbar disc transplantation and its effects on disc metabolism and morphology. METHOD: Eight mature mongrel dogs underwent disc transfer surgeries, in which the L2-L3 and L4-L5 intervertebral discs, with a small segment of adjacent superior and inferior vertebral body, were removed and transposed. The transplanted disc were stabilized by plates or by a flexible cable wire construct using Songer cables (DANEK, Inc., Memphis, TN). Unrestricted activity was allowed postoperatively. At 4 months, the spines were harvested, and the transplanted discs were evaluated biochemically and histologically. Intervening nontransplanted discs served as viable controls and thrice-frozen discs served as nonviable controls. Cell viability was assessed by measuring proteoglycan synthesis and DNA content. RESULTS: Proteoglycan synthesis (35S uptake normalized to DNA content) was maintained in transplanted anulus fibrosus tissue, but was decreased in nucleus pulposus samples (P < 0.05). DNA content was not altered significantly in the transplanted discs. Histologic analysis of the transplanted discs showed revascularization and remodeling of the bone adjacent to the disc and preservation of the lamellar architecture of the anulus fibrosus. The transplanted nucleus pulposus samples had chondrocyte-like cells present, but the staining characteristics of the nucleus material was variable. The contour of the transplanted disc endplates was irregular in all specimens. CONCLUSIONS: The structure and function of autograft intervertebral discs were maintained after disc transfer surgery; the transplant discs, however, were not completely normal in either their morphology or their metabolic functioning.