SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
The Transmandibular Distractor (TMD) is an intraoral expansion device for symphyseal widening by callus distraction. Its advantages include limited surgical exposure, skeletal anchorage, and expansion along the arch segment together with proportional and differential widening in the frontal plane.
With this case report we demonstrate a new technique useful in augmenting alveolar ridges after resection procedures or atrophic loss of volume. The augmentation is done by means of a new osteogenic distractor (manufactured by ACE Surgical Supply Co., Inc., Brockton, MA, USA), the distraction procedure is according to Ilizarov's principles.
Osteogenic distraction has been used for decades to lengthen limbs and now attention is focused upon its use within the craniofacial skeleton. This paper addresses distraction of the mandible. It is proposed that mandibular osteogenic distraction could be a possible adjunct to the orthodontic treatment of those adult patients with skeletal anomalies, who would benefit from combined orthodontic/orthognathic treatment. Three consecutive cases from one unit are presented, where adult patients with severe Class II division 1 malocclusions have undergone orthodontic treatment combined with mandibular osteogenic distraction, instead of conventional bilateral sagittal split osteotomies.
We carried out limb lengthening in rabbits and then transplanted osteoblast-like cells derived from the tibial periosteum to the centres of distracted callus immediately after distraction had been terminated. Two weeks later the transaxial area ratio at the centre of the distracted callus and the bone mineral density (BMD) were significantly higher in the transplanted group, by 21% and 42%, respectively, than in the non-injected group or the group injected with physiological saline (p < 0.05). Callus BMD as a percentage of density in uninvolved bone was also significantly higher in the transplanted group (p < 0.05) than in the other two groups, by 27% and 20% in the second and fourth weeks, respectively (p < 0.05). Mechanically, the callus in the transplanted group tended to be stronger as shown by the three-point bending test although the difference in fracture strength was not statistically significant. Our results show that transplantation of osteoblast-like cells promotes maturity of the distracted callus as observed at the second and fourth weeks after lengthening. The method appears promising as a means of shortening the consolidation period of callus distraction and decreasing complications during limb lengthening with an external fixator.
This study retrospectively evaluates the results of the management using the callus distraction method, of 19 patients who had developed bone defects following acute trauma. Sixteen patients were males, with a mean age of 19.4 years (6-41 years). Thirteen patients developed bone defects as a result of high-velocity gunshot injuries, and six had defects caused by traffic accidents. The location of 12 fractures was the tibia, and seven were in the femur. The mean follow-up period was 23.6 (12-40) months. The mean length of the bone defect was 6.8 cm (4-16 cm), the distraction index was 13.3 days/cm (7.5-18 days/cm) and the external fixation index was 36.6 days/cm (32.5-46 days/cm). Fifteen (9%) pintract infections were observed among those who underwent circular external fixation and four (10%) in cases who underwent unilateral external fixation. There were no deep infections. Refracture was noted in one patient (5%), and two (11%) had delayed union at the target site. One patient developed nonunion at the target site. For the treatment of large bone defects, the callus distraction method may be an alternative option to conventional treatment methods.
The rehabilitation of the mandible after ablation cancer surgery is a challenge. Furthermore, osteodistraction in the microvascular fibula flap makes it difficult to predict adequate bone lengthening. The aim of this article is to evaluate a protocol used to manufacture templates for measuring osteodistraction, in terms of force vectors and definitive height. An accurate prosthetic wax-up with guide pins measuring the quantity of bone lengthening must be performed to manufacture the template. This device may be used to establish the end of the osteo-distraction in respect to the vertical dimension of the definitive occlusion.
PURPOSE: Joint distraction has been used to treat osteoarthritis and was found to delay the need for arthrodesis or joint replacement. However, there has been little basic research on articulated joint distraction for the repair of osteochondral defects. We investigated the effects of joint distraction with motion after drilling on a fresh osteochondral defect in the weight bearing area of the rabbit knee joint. METHODS: A full thickness osteochondral defect was created in the weight bearing area of both medial femoral condyles of an adult Japanese white rabbit. After drilling of the defect, the experimental knee joint was distracted for 1.5 mm using a pair of external fixators to decrease compression force. The contralateral knee joint was used as a control with no apparatus. Gross findings and histological evaluation were assessed to study morphology of the repaired cartilage. RESULTS: A partial repair with cartilage-like tissue was observed in the joints of the experimental group at 4 weeks. While cartilage-like tissue stained with Safranin O was found in the experimental group at 8 and 12 weeks, destructive changes were observed in the control joints. Morphological changes were evaluated using the histological grading scale [Wakitani S, Goto T, Pineda SJ, et al. Mesenchymal cell-based repair of large, full-thickness defect of articular cartilage. J Bone Joint Surg Am 1994;76(4):579-92]. There was no significant difference between experimental and control groups at 4 weeks (mean 11.2 and 13.8 points, respectively). However, the mean scores of the experimental groups at 8 and 12 weeks (mean 6.8 and 7.5, respectively) were significantly better than those of the control groups at the same time points (mean 14 points each). Between the experimental groups, the scores at 8 and 12 weeks were both significantly better than those at 4 weeks. CONCLUSION: A combination of subchondral drilling, joint motion and distraction by an articulated external fixator promoted repair of a fresh osteochondral defect in the weight bearing area. Although distraction for 4 weeks was not a long enough period to repair the defect, distraction for 8 and 12 weeks resulted in a good outcome.
The following report refers to a well described surgical procedure using a prototype vertical distractor developed in Cologne in cooperation with Martin Medizintechnik GmbH. The surgical technique has been refined by an L-shaped osteotomy stabilized posteriorly by a miniplate to limit the amount of callus regeneration in the molar region where no increase in vertical height is required. The surgical technique with its advantages and one complication is described as used in four patients undergoing six distraction treatments.
For correction of malunited distal radius fractures, the use of the external fixator in radio-radial application was assessed. The device has been used for one-stage correction with corticocancellous bone blocks as well as with hemicallotasis for correction of dorsal angulation. The technical application is described and the use of the external fixator defined. Fourteen patients were treated with radio-radial application, seven of those were corrected with callus distraction. The mechanical possibilities of the fixator allowed complete correction of the malunion.
OBJECTIVES: Since the early 1990's when callus distraction of hypoplastic mandibles was developed, surgeons have been looking for a reliable method to monitor distraction treatment. X-rays films resulted in insufficient quality of images of low calcified structures and are only of little support in follow-up. Therefore, a standardised protocol using ultrasound was introduced. METHODS: 24 patients were included (aged 4 - 29 years with hemifacial microsomy [19], mandibulary micrognathia [5]), 20 intraoral (Howmedica-Leibinger/Mühlheim) and 9 extraoral distractors (Normed/Tuttlingen). Standard procedures for intra- and extraoral distraction were carried out and all postsurgical treatment steps were monitored by ultrasound. RESULTS: The mineralisation of the neocallus shows the following sequence: echogenic dots, needles directed along the distraction direction, bands, plaques, and modulation of the neocompacta. Additional therapeutically relevant questions of distraction distance, inflammation or occurrence of pus, arising during treatment were answered by sonography. Distance measurements could be performed reliably. CAT scan and MRI cannot be carried out because of metal artefacts. X-ray pictures like orthopantomogram and Clementschisch projection cannot show the early mineralisation and do not allow an exact distance measurement. CONCLUSIONS: Sonography is a effective, method to investigate the callus field without using X-rays and supports monitoring and decision making in distraction treatment of hypoplastic mandibles.
The purpose of this study was to determine whether compression and distraction applied to adjacent vertebrae in the calf tail could modulate vertebral growth. Seven 6-week-old calves had two pairs of adjacent tail vertebrae instrumented with an Ilizarov external fixator with calibrated springs designed to apply a 30-50-N axial load to the vertebrae. Data were obtained from 17 vertebrae loaded in compression and 4 vertebrae loaded in distraction. Vertebrae adjacent (cranial and caudal) to the instrumented vertebrae served as controls. The length of each vertebra on the postoperative radiograph was subtracted from the length of the same vertebra on the radiograph taken 6 months after the operation to calculate vertebral growth. The vertebrae loaded in compression had a growth rate of 68 +/- 42% of that of the controls. In contrast, the vertebrae loaded in distraction had a growth rate of 123 +/- 78% of that of the controls.
Explore the source record for details and available documents.
Corrective measures on the bone undertaken after the fusion of epiphyses are only possible through an initial break in its continuity. This paper deals with the different methods of osteotomy available to the orthopaedic or trauma surgeon. After introducing the terminology of the so-called "osteotomy", the vascularity of the bone, special features of the various osteotomy site, the different indications, and particular details of the operative procedures are discussed. Special emphasis is placed on minimally invasive techniques and osteotomies in the framework of callus distraction. In addition to established procedures a new sawing technique for the Küntscher's closed osteotomy is described.
We examined the ratio between actual maxillary distraction and the distraction of the rigid external distraction device (Rigid external distraction (RED) system) used for maxillary distraction in patients with a cleft deformity. Twelve patients were examined. The amount of maxillary advancement was measured on lateral cephalograms and divided by the activation amount on the RED system. The value obtained was represented as the distraction ratio of the maxilla to the system. The mean ratio in 10 patients with complete cleft lip, palate, and alveolus (complete cleft) was 0.24. However, the ratios in two patients with cleft lip and alveolus or soft cleft palate (incomplete cleft) were considerably higher than the mean ratios in patients with complete cleft. When the maxilla is distracted in patients with complete cleft using the RED system, the amount of activation on the system needs to be about four times the amount of planned maxillary distraction. However, the distraction ratio may be affected by the type of cleft.
The purpose of this clinical report is to present the distraction technique for advancement of the frontofacial skeleton as a unit. Our 14-year-old patient was diagnosed with Carpenter's syndrome and kleblattschädel deformity at birth. At other centers the patient underwent corrective surgeries, including repeated fronto-orbital advancement in an attempt to correct the residual deformity. This has resulted in bony malunion and recurrent deformity, and it has left the patient with no available donor sites for harvesting of bone graft. The patient had class III malocclusion, severe midfacial and frontal deficiency, and relative turricephaly. We performed frontofacial osteotomies and placement of the distraction devices. Distraction of 20 mm was accomplished, correcting the exophthalmos and midface retrusion and producing class I dental occlusion. We conclude that distraction is an optional surgical method that can be applied in selected cases for advancement of the entire frontofacial skeleton.
In 24 beagles, lengthening of the right tibia was performed by callus distraction after osteotomy and application of a ring fixator. Distraction was started the fifth day after surgery with a distraction rate of 0.5 mm twice per day and ended after 25 days. A control group of six additional dogs underwent tibial osteotomy and external fixation without distraction. Twelve animals with leg lengthening and three animals without leg lengthening were sacrificed immediately after the distraction period of 25 days (Group A), the remaining 15 dogs were sacrificed after an additional consolidation phase of another 25 days (Group B). From the distracted right leg and from the left control side of each animal, the tibial and peroneal nerves were removed and studied by means of morphometric analysis of semithin sections and electron microscopic study. The authors reported only minor alterations of the myelinated nerve fibers consisting in relatively thin myelinated remyelinating nerve fibers, single axon degeneration, or macrophages. There was no axonal sprouting. In contrast, electron microscopic study disclosed signs of late Wallerian degeneration and axonal regeneration of the nonmyelinated axons. Morphometric analysis of the peroneal nerves revealed a significant increase of fiber density and a reduced mean axon and fiber diameter in the consolidation period (Group B). Similar changes were found in the tibial nerves in Group A and disappeared in the consolidation phase (Group B). These features indicate that callus distraction leads to moderate degenerative changes, followed by repair mechanisms, almost complete recovery, and some nerve fiber growth.
Distraction-lengthening technique is quite useful in a variety of congenital hand deformities with hypoplastic, or primary normal but secondary shortened (constriction ring syndrome) finger rays. It appears that around the age of two years is the earliest practical time to start distraction; certainly distraction and secondary surgical procedures to improve function should be completed before school entry age whenever possible. Between June 1990 and March 1993, nine distraction lengthening procedures (5 thumbs, 1 index, 3 little fingers) in five patients presenting with congenital hand deformities, were carried out. Although restoring length to the finger, lengthening does not provide normal circumference or, of course, interphalangeal joint motion. Amelioration in function seems to be more important than the esthetic gain. Distraction lengthening tolerates only few errors of indication, operative technique, and/or postoperative management. A high compliance of the patient and her/his parents as well as a close follow-up by an experienced surgeon, are mandatory for a good result. A variety of possible complications have been described. Generally, complication risk increases in cases of simultaneous and multiple level lengthening. Provided adequate operative technique and postoperative care, superficial pin infection and fracture in the region of distraction are the major complications. Contrary to adults, sufficient bone formation by distraction is the rule in children. Therefore, the distraction-lengthening technique is preferred to the distraction-interposition technique in the treatment of congenital hand deformities. The latter should only be used as a salvage procedure in the rare cases of insufficient callus formation. Because of the missing growth potential and reduced joint mobility, distraction lengthening is the therapy of second choice when compared to microvascular second toe transplantation.
Explore the source record for details and available documents.