Lee S. Segal

Calcaneal gait in spastic diplegia after heel cord lengthening: a study with gait analysis

Calcaneal gait or deformity can be significant complication after heel cord lengthenig. After heel cord lenghtening, 20 children wirh spastic deiplegia were evaluated by gait analysis to define calcaneal gait objectively and describe associated morbidity. Mean age 5 years 2 months (range 2 years 7 months to 8 years 2 months), and mean length of follow-up was 5 years 8 months (range 1 years 1 month 11 year 3 months). Calcaneal gait was defined as dirsuflexion 1 SD beyond the mean in the sagittal plane for all phases of stance. In creased ankle dorsiflexion during midstance most accurately predicts calcaneal gait. Through gait analysis, a 30% (6 of 20) prevalence of calcaneal gait suggests that an incresed incidence of caolcaneal fair may be present after heel cord incidence of calcaneal gait may be present after heel cord lengthening.

Growth disturbances of the proximal femur after pinning of juvenile slipped capital femoral epiphysis

Premature closure of the capital femoral physis after pin fixation of slipped capital femoral epiphysis (SCFE) in the juvenile population (at least 1 year less than the established mean) can lead to growth disturbances of the proximal femur. A retrospective review of 21 patients (33 hips) who had a pinning of a juvenile SCFE was performed. Growth disturbances including greater trochanteric overgrowth, coxa vara, and coxa breva were noted in 64% of the hips. An 80% incidence of bilateral involvement was noted in the juvenile group. Consideration should be given to prophylactic pinning of the contralateral hip and use of a smooth pin construct to prevent premature closure of the growth plate in children with significant growth remaining.

Metaphyseal fractures mimicking abuse during treatment for clubfoot

Background. Metaphyseal injuries resembling the classic metaphyseal lesion (CML) of abuse may occur as the result of serial casting during treatment of clubfoot deformity. Mentioned in the orthopedic literature in 1972, this iatrogenic fracture has not been described in the radiologic literature nor has the similarity to injuries occurring with abuse been previously recognized. Objective. To describe the mechanism and radiographic appearance of metaphyseal injury observed during serial casting of clubfoot. Note similarities to the CML of abuse. Materials and methods. Eight children ranging in age from 1 to 4 months underwent casting for clubfoot. Five orthopedic surgeons from three different institutions performed the casting. Two patients had spina bifida and one, arthrogryposis. A complete skeletal survey was performed on one child who was abused; there was no suspicion of abuse in the remaining seven. Results. All children manifest injury with periosteal new bone. One child had clear evidence of abuse with 24 rib fractures. X-rays of lower extremities in short leg casts revealed bilateral tibial metaphyseal fractures. Four other children had metaphyseal fractures resembling the CML of abuse, and three developed an area of sclerosis within the metaphysis. Conclusion. In the setting of serial casting for equinovarus deformity, metaphyseal injury even the CML of abuse may be noted. Since inflicted injuries are almost always unobserved and explanations rarely offered, the fact that the CML occurs as a result of orthopedic maniuplation may offer some further insight concerning the pathogenesis of this well-described abuse injury.

Potential complications of posterior spine fusion and instrumentation in patients with cerebral palsy treated with intrathecal baclofen infusion.

Study Design. The authors evaluated a case series of 5 patients with cerebral palsy and a previously placed subcutaneous reservoir for continuous intrathecal baclofen infusion to control spasticity who underwent spinal arthrodesis with posterior instrumentation for progressive neuromuscular scoliosis deformities. Objectives. To present our preliminary experience and complications with posterior spine fusion in patients with cerebral palsy and continuous intrathecal baclofen infusion and provide a literature review. Summary of Background Data. Numerous studies have reported complications associated with intrathecal baclofen infusion, many of these catheter-related. Few reports address complications associated with the intrathecal baclofen infusion, including progressive spinal deformities and complications following spinal arthrodesis. Methods. Five patients with spastic quadriplegia cerebral palsy had spine fusions for progressive neuromuscular scoliosis. The mean age at surgery was 14.5 years. The mean preoperative major curve was 73° and mean pelvic obliquity was 19°. The patients’ medical records were reviewed for complications following reinsertion of the intrathecal catheter following posterior spine instrumentation and arthrodesis, and for progression of the neuromuscular scoliosis, before and after intrathecal baclofen infusion was initiated. Results. Two patients presented with low-pressure headaches in the postoperative period, resulting from cerebrospinal fluid leak following subarachnoid catheter reinsertion and posterior instrumentation. Four patients documented progression of the major scoliosis curve after intrathecal baclofen infusion was begun. A mean progression of 44° occurred over a mean period of 11 months before the spinal arthrodesis. Conclusions. Low pressure headaches resulting from a cerebrospinal fluid leak following catheter reinsertion may occur in the postoperative period. Preoperative concerns with the baclofen pump reservoir placed subcutaneously and pressure sores were not seen with careful prone positioning on a 4-poster frame. Progression ofscoliosis in patients with cerebral palsy requiring spinal arthrodesis was demonstrated in 4 of the patients after continuous intrathecal baclofen was started. The progression of the spinal deformity as a consequence of growth, natural history, or the intrathecal baclofen infusion is unknown at the present time.

Biomechanical analysis of in situ single versus double screw fixation in a nonreduced slipped capital femoral epiphysis model.

Abstract: Slipped capital femoral epiphyses (SCFE) were created in 24 pairs of immature bovine femurs. In 17 pairs of femurs, the slip was left nonreduced (one-third diameter of physis), and in 7 pairs, the slip was reduced. Stabilization of the slips was with either 1 or 2 threaded 6.5-mm screws in a compression mode. The specimens were subjected to shear or torsional loading forces to failure, with the goal of trying to reproduce clinical conditions of in situ screw fixation for acute or unstable SCFE. In the nonreduced model, double-screw fixation was 312% stiffer than single-screw fixation under torsional loading. In the reduced model, double-screw fixation was 137% stiffer than single-screw fixation under torsional loading. The increased rotational stability of double-screw fixation under torsional loading conditions may justify its use in in situ stabilization of acute or unstable SCFE.

The contribution of the ossific nucleus to the structural stiffness of the capital femoral epiphysis: a porcine model for DDH.

The preosseous femoral head is thought to be vulnerable to compressive ischemic injury during the treatment of developmental dysplasia of the hip. The ossific nucleus has been proposed to increase the mechanical strength of the capital femoral epiphysis (CFE) and to decrease the risk of avascular necrosis. Sixty mixed-breed fetal and postgestational femoral head specimens were evaluated for structural stiffness in relation to the size of the ossific nucleus within the CFE. The structural stiffness of the CFE in the porcine model was found to increase exponentially with the size of the ossific nucleus. A finite-element model revealed that the presence of an ossific nucleus occupying 40% of the epiphyseal volume reduced the compressive strain in the region of the posterior-superior branch of the medial circumflex artery by an average of 54%. The results of this study support the hypothesis that the presence of the ossific nucleus may protect the CFE from compressive ischemic injury in the treatment of DDH.

Lyme Disease Presenting as Popliteal Cyst in Children

Lyme disease is the most common tick-borne disease in North America. Our review of the literature found few reports of Lyme disease presented in the orthopaedic literature. However, Lyme disease presenting as a popliteal cyst, with or without rupture, is rarely reported. We present 4 cases of Lyme disease that initially presented to our pediatric orthopaedic clinic for treatment of a popliteal cyst. The early diagnosis and treatment of Lyme disease may help prevent the often-devastating long-term sequelae of Lyme disease. The goal of this article is to increase the awareness of Lyme disease presenting in children as a popliteal cyst.

Independent analysis of a clinical predictive algorithm to identify methicillin-resistant Staphylococcus aureus osteomyelitis in children.

Background: The number of serious, life-threatening musculoskeletal infections in children due to methicillin-resistant Staphylococcus aureus (MRSA) infections is increasing. The early identification of the bacteria causing osteomyelitis is critical to determine the appropriate antibiotic treatment. A recent study proposed a clinical algorithm to predict which infections were caused by MRSA by stratifying basic clinical values at the time of admission for children with osteomyelitis. The purpose of this study is to apply that predictive algorithm on an independent patient population to determine its wider applicability. Methods: This was a retrospective chart review at a tertiary care children’s hospital. All children who were treated for a culture-positive osteomyelitis were identified over a 3-year period. The previously reported predictors, determined by multivariate regression analysis, of MRSA infection (temperature >38°C, hematocrit <34%, white blood cell count >12,000/µL, and C-reactive protein >13 mg/L) were determined for each patient. The number of positive predictors was then correlated with the percentage of cases that were MRSA positive. Results: A total of 58 patients with culture-positive osteomyelitis were identified from 2008 to 2010. Sixteen of the infections were caused by MRSA (overall 26%). The percentage of patients with MRSA osteomyelitis according to the number of risk factors were as follows: all 4 risk factors, 50% (1 out of 2 patients); 3 risk factors, 42% (5 out of 12 patients); 2 risk factors, 21% (4 out of 19 patients); 1 risk factor, 50% (6 out of 12 patients); and 0 risk factor, 0% (0 out of 13 patients). Conclusions: The previously reported clinical predictive algorithm had a relatively poor diagnostic performance in this independent patient population. Specifically, the percentages of MRSA were the same for 1 risk factor compared with 4 (50%). Differences in bacteria strain, host responses, and a variety of other confounding variables could be responsible for these differences. Specific genetic markers may be the best early test to identify MRSA infections in the future. Level of Evidence: Level III—case-control series.

Custom 95° condylar blade plate for pediatric subtrochanteric femur fractures

Subtrochanteric fractures in the older child and adolescent often are not amenable to conservative methods of treatment. The anatomic constraints of the proximal femur including the small diameter of the femoral neck and the presence of the capital femoral physis may limit the type of internal fixation used in these patients. This article presents our preliminary experience with a custom 95 degree condylar blade plate for subtrochanteric fractures in older children and adolescents.

Suspected nonaccidental trauma and femoral shaft fractures in children.

The question of suspected nonaccidental trauma as a possible cause of injury for femoral shaft fractures in children is a troubling but common issue facing orthopedic surgeons. The purpose of this study is to analyze femoral shaft fractures at a major pediatric level I trauma center in a large metropolitan area over a 5-year period to determine the incidence of suspected nonaccidental trauma and the risk factors associated with that diagnosis. This study is a retrospective review of all children younger than 5 years at a large trauma center in a southwestern metropolitan area who presented with a femoral shaft fracture. Patient charts were reviewed to determine demographics, mechanism of injury, and fracture type. Referrals to social work and Child Protective Services were also reviewed to determine an overall incidence of suspected nonaccidental trauma.Over the 5-year study period, 137 patients presented to our institution with a femoral shaft fracture. Mean patient age at the time of injury was 2.2 years (range, 1 month to 4 years). Overall, 43 patients with a mean age of 1.8 years were determined to have injuries suspicious of nonaccidental trauma and were referred to Child Protective Services, giving an overall incidence of 31%. Age younger than 1 year was a highly significant risk factor for suspected nonaccidental trauma. Of the 20 children younger than 1 year, 18 (90%) were referred to Child Protective Services, comprising 42% of those children suspicious of nonaccidental trauma. The presence of either Medicaid or no insurance was a highly statistically significant risk factor for suspected nonaccidental trauma.