Intranasal deferoxamine affects memory loss, oxidation, and the insulin pathway in the streptozotocin rat model of Alzheimer's disease.

Accumulation of metal and the accompanying increase in oxidative stress and inflammation plays an important role in neurodegenerative disease. Deferoxamine (DFO) is a metal chelator found to be beneficial in several animal models of neurodegenerative disease and insult including Alzheimer's disease, Parkinson's disease, stroke, and subarachnoid hemorrhage. In this study, we determine whether intranasally (IN) administered DFO is beneficial in the intracerebroventricular streptozotocin (ICV STZ) rat model of sporadic Alzheimer's disease, which is different from previous models in that it exhibits dysregulation of insulin metabolism as well as oxidative stress and inflammation. Surgical induction of the model included ICV injections of either STZ or citrate buffer (sham in rats), which were treated IN with either saline or DFO (n=10-15/group). Treatment started either before or after injection of STZ to induce the model, and continued throughout the study. IN treatment continued three times per week for three weeks before behavior tests started followed by eventual euthanasia with tissue collection. Spatial memory tests with the Morris water maze showed that STZ rats treated with IN DFO both before and after model induction had significantly shorter escape latencies. Pre-treatment with IN DFO also significantly decreased footslips on the tapered balance beam test. Brain tissue analyses showed DFO treatment decreased oxidation as measured by oxyblot and increased insulin receptor expression. These results further support the potential of IN DFO for use as a treatment for Alzheimer's disease, and show benefit in a non-amyloid/tau rodent model.

Operative treatment of bicondylar intraarticular fractures of the distal humerus.

Orthopedists' lack of consensus on treatment regimens for bicondylar fractures of the distal humerus warrants further review of this uncommon fracture. We present a series of 17 bicondylar fractures of the distal humerus that had a minimum follow up of 2 years. Of these fractures, the 13 that were treated exclusively with internal fixation had 92% excellent or good results. The operative technique we describe is modified from the technique recommended by the AO group. We have found it helpful to use the radial column as the site of primary fixation with a 3.5 mm dynamic compression plate in the sagittal plane. Additional fixation is provided by a reconstruction plate placed posteriorly on the ulnar column in the coronal plane. This system of dual plates in perpendicular planes provides rigidity for early motion which, when supervised, is beneficial to a satisfactory outcome.

Premature greater trochanteric epiphysiodesis secondary to intramedullary femoral rodding.

Five skeletally immature patients developed premature closure of the greater trochanteric physis consequent to placement of an intramedullary rod for primary treatment of a femoral diaphyseal fracture. Each patient developed increased femoral neck valgus as compared with the contralateral hip. To date, however, none of these patients has had any functional disability, although one has developed mild radiographic subluxation. In addition, anatomic specimens demonstrated the likelihood of traversing a portion of the greater trochanteric physis. Other methods of fracture treatment, either operative or nonoperative, should be considered in skeletally immature patients who have not entered the final phase of skeletal maturation characterized by subchondral "sclerosis" along the greater trochanteric physis.

Tibia valga after proximal metaphyseal fractures in childhood: a normal biologic response.

Seventeen children with 19 proximal tibial metaphyseal fractures were followed-up between 2 and 7 years after injury. Detailed measurements of the metaphyseal/diaphyseal/metaphyseal distances medially and laterally on the injured and noninjured sides demonstrated overgrowth. In four patients, the medial distance of the injured tibia was longer than the lateral distance, which was the same distance as the uninjured tibia. In 11 patients, there was an overgrowth of both the medial and lateral sides of the injured tibia, compared to the unijured tibia, and in each instance, the medial distance of the injured tibia was always longer than the lateral. In a patient with bilateral metaphyseal fractures, the medial length exceeded the lateral length in both tibias. In the child with metaphyseal and diaphyseal fractures, the medial side of the tibia with the metaphyseal fracture was the longest of the four measurements. In five of six patients with Harris lines, there was distal as well as proximal tibial metaphyseal overgrowth, but the distal line was always parallel to the physis and did not contribute to the valgus angulation. Thus there was not only a generalized increased growth proximally and distally, but there also was an eccentric proximal medial overgrowth in every patient.

Humerus varus: a complication of neonatal, infantile, and childhood injury and infection.

Sixteen cases of humerus varus consequent to proximal humeral fracture and osteomyelitis are described. A similar, but variably severe pattern of progressive deformity occurred in all cases. The medial region of the proximal humeral physis usually either developed slowly or failed to develop, whereas the lateral region developed more normally. This caused progressive angular rotation of the proximal humeral epiphysis and physis, so that the lateral region of the growth plate, in its most severe expression, was almost aligned with the longitudinal axis of the shaft. In the majority of the cases, there was a medial-metaphyseal lucency and adjacent medial-osseous bridge. In some cases, a flattened epiphysis and central bridge were present, with less varus deformation with progressive growth. Shortening of the humerus occurred in all cases. Functional impairment, usually a mild to moderate limitation of glenohumeral abduction, was infrequent, even when the dominant arm was involved. Axial lengthening may yet be undertaken. Surgical realignment with a corrective (valgus) osteotomy of the proximal humerus does not, however, appear functionally necessary for all patients.

Orthopaedic manifestations of Rett syndrome.

We reviewed nine patients with Rett syndrome, a progressive encephalopathy that is being diagnosed more frequently in the United States. It occurs in females, causing mental deterioration, autistic behavior, and classic hand-wringing motion. The orthopaedic manifestations include scoliosis, lower extremity contracture, and coxa valga. Bracing and surgery are indicated to prevent or correct deformity and maintain ambulation.

Caudal regression: a review of seven cases, including the mermaid syndrome.

Caudal regression consists of sacral agenesis combined with variable lower extremity deformities. The patients have contractures of the lower extremities, hip dislocations, neurologic impairment, and spine instability. Treatment consists of soft tissue releases, osteotomies, or orthotics. The goal of orthopaedic intervention is proper seating and standing, which may be achieved without amputation. In our patients, the lower extremity deformities were corrected surgically, but long-term function is unknown. We report the problems and treatment of seven patients with caudal regression syndrome, including the only known survivor with sirenomelia (mermaid syndrome), who underwent separation of the lower extremities.

Orthotic treatment of infantile tibia vara.

Difficulty differentiating physiologic genu varum from early Blount's disease persists. Drennan's metaphyseal-diaphyseal (MD) angle remains the most consistently valuable radiographic parameter despite measurement error. Clinical risk factors also should be considered. All patients receiving orthoses for genu varum since 1985 were reviewed. The focus of the study was those patients with an MD angle of >16 degrees or between 9 and 16 degrees with a clinical risk factor for progression. Risk factors considered were ligamentous instability, obesity, asymmetry, and being female, black, or Hispanic. Thirty-eight patients with 60 tibiae were included. The success rate was 90%. Risk factors for failure (six cases) were instability, obesity, and delayed bracing. In cases with MD angles >16 degrees, the success rate was 86%. The results of orthotic treatment, restricted to patients meeting the stated parameters, represent improvement on the reported natural history.

Ilizarov treatment of congenital pseudarthroses of the tibia.

Eleven children with congenital pseudarthrosis of the tibia were treated with the Ilizarov device. This was successful in nine of 11 patients with an average of 322 days in the fixator and 1.6 additional surgeries. Two patients eventually had amputations. These results demonstrate this to be an effective tool for this complex condition, but amputation should be considered if union is not achievable with this method and other procedures have previously been attempted.

Use of the reciprocating gait orthosis in myelodysplasia.

There are advantages to an upright posture and ambulation in pediatric myelodysplasia patients. The reciprocating gait orthosis (RGO) is a useful tool to enable this activity in selected individuals. We evaluated the long-term usage, pitfalls, and contraindications of this orthosis. Mean daily usage was 6.9 h/day, requiring an average of 10 min to don or doff; all patients required assistance. Obesity, advanced age, lack of patient or family motivation, scoliosis, and spasticity were significant negative factors in long-term usage of the RGO. Good upper extremity strength, trunk balance, previous standing or walking, and active hip flexion were important positive variables. Eleven of 21 patients did not persist with long-term usage of this orthosis, averaging 25.8 months of usage. An energy study was performed on three patients, comparing the efficiency of reciprocating gait and swing-through gait. All three were more energy efficient and two were faster with the swing-through gait but each preferred the reciprocating pattern. Care should be taken when selecting patients for RGO usage because not all children with myelomeningocele are able to function effectively with this orthosis.

Treatment of femoral fractures in children by pediatric orthopedists: results of a 1998 survey.

SUMMARY: This study aimed to determine treatment preference of various femoral fracture patterns in children by pediatric orthopedists and whether it is practice dependent. In September 1998, members of the Pediatric Orthopedic Society of North America were surveyed to determine their current preferences in treating each of four middle one-third femoral fracture patterns in four age groups. Forty-four percent (286/656) of those surveyed responded. For each fracture pattern, operative treatment was increasingly preferred over nonoperative as patient age increased, and the preferred treatments within the operative and nonoperative categories changed significantly as patient age increased. Fourteen specific cases of femoral head avascular necrosis were noted after rigid reamed and unreamed rodding. There is a statistically significant trend by pediatric orthopedists to treat older children's femur fractures operatively and younger children's nonoperatively. The consensus treatment is age dependent. The numerous cases of avascular necrosis after rigid rodding are a concern.