Transposition of the apophysis of the greater trochanter for reconstruction of the femoral head after septic hip arthritis in children: 4 children followed for more than 15 years

Background and purpose Total necrosis of the femoral head after infection in children during their first months of life gives a dislocated hip with severe leg shortening. A new femoral head can be achieved with subtrochanteric osteotomy and transposition of the apophysis of the greater trochanter into the acetabulum. Previous reports have dealt with short-term results (up to 12 years). Here I present some results of this procedure 15–24 years after operation. Patients and methods 4 children aged 1–6 years with complete necrosis of the femoral head were operated on with transposition of the greater trochanter. Secondary shelf plasty was performed later in 1 child, distal femoral epiphysiodesis in another, and femoral bone lengthening in 1 child. The mean follow-up period was 19 (15–24) years. Results A new femoral head developed in all hips. 2 of them had a spherical head with a good acetabular cover, and without any osteoarthritis except for slight reduction of cartilage height. These hips were painless, with a mobility that allowed good walking function after 16 and 24 years, respectively. In the other 2 patients, in which there was a severe acetabular dysplasia at the primary operation, the new femoral head was somewhat flattened; painful osteoarthritis led to hip replacement 15 and 21 years after trochanter arthroplasty. Even these patients had a relatively good walking function until the last couple of years before hip replacement. Maximum leg length discrepancy was 7 cm. Interpretation Trochanter arthroplasty with subtrochanteric osteotomy in total femoral head necrosis after septic arthritis in children may give satisfactory long-term results provided adequate acetabular cover is obtained. Although the method cannot provide a normal hip, it can contribute to less length discrepancy, less pain, improved gait, and more favorable conditions for later hip replacement

Dimethyl fumarate attenuates reactive microglia and long-term memory deficits following systemic immune challenge

BACKGROUND: Systemic inflammation is associated with increased cognitive decline and risk for Alzheimer's disease. Microglia (MG) activated during systemic inflammation can cause exaggerated neuroinflammatory responses and trigger progressive neurodegeneration. Dimethyl fumarate (DMF) is a FDA-approved therapy for multiple sclerosis. The immunomodulatory and anti-oxidant properties of DMF prompted us to investigate whether DMF has translational potential for the treatment of cognitive impairment associated with systemic inflammation. METHODS: Primary murine MG cultures were stimulated with lipopolysaccharide (LPS) in the absence or presence of DMF. MG cultured from nuclear factor (erythroid-derived 2)-like 2-deficient (Nrf2 -/- ) mice were used to examine mechanisms of DMF actions. Conditioned media generated from LPS-primed MG were used to treat hippocampal neuron cultures. Adult C57BL/6 and Nrf2 -/- mice were subjected to peripheral LPS challenge. Acute neuroinflammation, long-term memory function, and reactive astrogliosis were examined to assess therapeutic effects of DMF. RESULTS: DMF suppressed inflammatory activation of MG induced by LPS. DMF suppressed NF-κB activity through Nrf2-depedent and Nrf2-independent mechanisms in MG. DMF treatment reduced MG-mediated toxicity towards neurons. DMF suppressed brain-derived inflammatory cytokines in mice following peripheral LPS challenge. The suppressive effect of DMF on neuroinflammation was blunted in Nrf2 -/- mice. Importantly, DMF treatment alleviated long-term memory deficits and sustained reactive astrogliosis induced by peripheral LPS challenge. DMF might mitigate neurotoxic astrocytes associated with neuroinflammation. CONCLUSIONS: DMF treatment might protect neurons against toxic microenvironments produced by reactive MG and astrocytes associated with systemic inflammation

Acetabular dysplasia and hip dislocation after selective premature fusion of the triradiate cartilage. An experimental study in rabbits

Premature fusion of the triradiate cartilage was obtained surgically in 10 three-week-old rabbits, and compared with isolated fusion of the ilio-ischial and of the ilio-pubic limbs of the triradiate cartilage in two further groups of 10 rabbits. Complete fusion caused acetabular dysplasia five weeks after operation in all animals and hip dislocation at nine weeks in half of them; ilio-ischial fusion had a comparable effect. Ilio-pubic fusion had only a minimal effect on acetabular development. The posterior position of the ilio-ischial limb in the acetabulum and its predominance in the formation of the triradiate cartilage in quadrupeds may have contributed to its decisive effect on acetabular development

Bridging large defects in bone by demineralized bone matrix in the form of a powder. A radiographic, histological, and radioisotope-uptake study in rats

Demineralized bone powder was used as an osteoinductive substance to bridge very large defects (more than 50 per cent of the total length of the bone) in one radius of each of thirty-three rats. An identical defect was produced in the contralateral radius of each animal for use as a control. The defect on the control side was left unbridged or was bridged by large chips of autologous bone or an autologous inlay graft. All rats showed formation of new bone throughout the length of the radial defect only on the side in which the demineralized bone powder had been implanted. The control side, in which an autologous graft in the form of chips or inlay had been implanted, showed resorption of the graft. The maximum rate of formation of bone occurred fifteen to twenty-one days after implantation of the demineralized bone powder. At thirty-five days, the experimental defect was fully bridged, forming solid bone, in 71 per cent of the rats, and the remaining 29 per cent showed bridging of 95.8 per cent of the length of the defect, with union on one side. Analysis of the sequential radiographs, technetium-99m scans, and histological findings showed that the formation of bone and bridging of the defect were superior on the side in which the demineralized bone powder had been implanted compared with the side in which pieces of autologous bone or an autologous inlay graft had been used.(ABSTRACT TRUNCATED AT 250 WORDS

Bilateral post-traumatic acetabular dysplasia

Traumatic disruption of the acetabular triradiate cartilage is an infrequent injury. When it occurs in early childhood, it may lead to growth changes in acetabular morphology. The morphology of this kind of acetabular dysplasia is uniform and differs significantly from that seen in classic developmental dysplasia of the hip. We present a case of bilateral post-traumatic acetabular dysplasia, which to our knowledge has not been reported. The morphology and the symptoms of impingement and periacetabular osteotomy of the hip joint are discussed