Power Doppler assessment of vascular changes during fracture treatment with low-intensity ultrasound.
(73/1005)
OBJECTIVE: To study the use of power Doppler sonography for assessing changes in vascularity during treatment of fracture sites with low-intensity ultrasound. METHODS: In 6 dogs (3 pairs), subcutaneous dissection of the midshaft of the ulna allowed symmetrical osteotomies to be made with a reciprocation saw. Three dogs were treated and 3 were used as controls. The fracture site was subjected to 1.5-MHz low-intensity ultrasound (30 mW/cm2) for 20 minutes daily from a therapeutic ultrasonic device. Gray scale sonography was performed to evaluate the fracture site. Power Doppler sonography was used to assess flow patterns at the fracture site and surrounding soft tissue. A sonographic contrast agent was administered intravenously. The dose was 0.2 mL/kg. RESULTS: Power Doppler sonography showed an increase in flow around the fracture site in the treated dogs compared with that in control dogs. Color pixel values on day 7 were 3-fold higher in treated legs than control legs and on day 11 were 33% higher in treated legs than control legs. Enhancement after contrast agent administration was consistently higher in treated legs than control legs. CONCLUSIONS: Power Doppler sonography showed increased vascularity around the fracture sites in treated dogs with and without contrast agent administration. (+info)
Spine fusion using cell matrix composites enriched in bone marrow-derived cells.
(74/1005)
Bone marrow-derived cells including osteoblastic progenitors can be concentrated rapidly from bone marrow aspirates using the surface of selected implantable matrices for selective cell attachment. Concentration of cells in this way to produce an enriched cellular composite graft improves graft efficacy. The current study was designed to test the hypothesis that the biologic milieu of a bone marrow clot will significantly improve the efficacy of such a graft. An established posterior spinal fusion model and cancellous bone matrix was used to compare an enriched cellular composite bone graft alone, bone matrix plus bone marrow clot, and an enriched bone matrix composite graft plus bone marrow clot. Union score, quantitative computed tomography, and mechanical testing were used to define outcome. The union score for the enriched bone matrix plus bone marrow clot composite was superior to the enriched bone matrix alone and the bone matrix plus bone marrow clot. The enriched bone matrix plus bone marrow clot composite also was superior to the enriched bone matrix alone in fusion volume and in fusion area. These data confirm that the addition of a bone marrow clot to an enriched cell-matrix composite graft results in significant improvement in graft performance. Enriched composite grafts prepared using this strategy provide a rapid, simple, safe, and inexpensive method for intraoperative concentration and delivery of bone marrow-derived cells and connective tissue progenitors that may improve the outcome of bone grafting. (+info)
Osteosynthesis of distal radial fractures with a volar locking screw plate system.
(75/1005)
We developed a locking screw plate system for the stabilisation of distal radial fractures, which can be inserted through a standard volar approach and in which the locking mechanism allows early post-operative mobilisation. Forty-nine patients with 50 fractures underwent surgical treatment; 66% were type C fractures. The mean follow-up was 26 months. According to the scores of Gartland and Werley and Green and O'Brien, 92% and 68% respectively had an excellent or good outcome; 46% were radiologically identical to the uninjured side and in 42% the reduction remained unchanged after 2 years. The most frequent complication was rupture of the flexor pollicis longus tendon, which occurred in six cases (12%) at a mean of 10 months after operation. (+info)
Functional bracing in the treatment of delayed union and nonunion of the tibia.
(76/1005)
We treated 16 delayed unions and 57 nonunions of the tibial diaphysis with a below-the-knee functional brace. In 48 cases, bracing was preceded by fibular ostectomy, and ten patients had an additional bone graft. We were able to follow 67 patients, of whom six (8.7%) failed to respond to treatment. In patients with nonunion, bony healing occurred with a median of 4 months. There was no difference in the speed of healing according to the level of the defect. Shortening of the limb following ostectomy of the fibula had a mean of 3 mm in the delayed-union group and 5 mm in the nonunion group. (+info)
Distraction osteogenesis by Ilizarov and unilateral external fixators in a canine model.
(77/1005)
We studied distraction osteogenesis in canine experimental model using two types of external fixators, Ilizarov (n=6) or AO unilateral (n=9) external fixator. Distraction started 1 week after surgery (2 x 0.5 mm/day) and lasted for 3 weeks. Specimens were harvested from weeks 7 through 12. The outcome was assessed by X-ray, histology, histomorphometry and microradiography. Bone regeneration as observed by X-rays was satisfactory and similar in both groups. Both endochondral ossification and intramembranous ossification were found simultaneously in both groups. In both groups, bone formation parameters were significantly higher in the area of consolidating bone. No differences in histomorphometric parameters existed between the groups. In the study period, the bone formation was enhanced and prevailed in the distraction area. This study demonstrated the utility of the canine experimental model for the study of distraction osteogenesis. (+info)
Efficacy of contained metaphyseal and periarticular defects treated with two different demineralized bone matrix allografts.
(78/1005)
The efficacies of two different allografts, Grafton (demineralized bone matrix [DBM] in a glycerol carrier) and Orthoblast (DBM in a reverse thermal poloxamer carrier) were examined from cases involving periarticular fractures. Demographic, perioperative, and outcome data for patients with periarticular fractures who underwent a prospectively designed protocol for bone grafting were compiled, with 15 cases using Orthoblast and 13 using Grafton. A successful graft was defined as healing on the first graft attempt without complications. Healing was determined by radiographic studies and clinical evaluation. The successful graft rates of Orthoblast and Grafton were 15/15 and 9/13, respectively. (+info)
Use of the coventry infant hip screw in the treatment of nonunion of fractures of the distal humerus.
(79/1005)
Between 1993 and 2000 we treated 14 patients with nonunion of fractures of the distal humerus; 11 had already had previous fixation which had failed. The mean time to surgery was 21 months after injury. All the fractures were very low which made it difficult to obtain a firm hold of the small distal fragment. The problem of fixation was addressed by inserting a Coventry infant hip screw into the humeral condyles. The screw has a thread of wide diameter which gives excellent purchase on the small distal fragment. The condyles can then be compressed on to the humeral shaft using a 4.5 mm narrow tibial dynamic plate. Of these 14 difficult cases of nonunion, 12 progressed to union. (+info)
Complete remodelling of displaced fractures of the neck of the phalanx.
(80/1005)
Fractures of the neck of the phalanx of the finger are uncommon, but problematic, injuries in children. Displaced fractures may heal with malunion leading to loss of movement or angular deformity. Remodelling of the phalangeal neck is reported to be minimal because of the distance of the fracture from the physis. We report three displaced fractures in two children who presented late. The fractures were treated conservatively and remodelled completely. Both patients regained full movement of the fingers. (+info)