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PubMed2004

Bifocal compression-distraction in the acute treatment of grade III open tibia fractures with bone and soft-tissue loss: a report of 24 cases.

OBJECTIVE: To evaluate the results of bifocal compression-distraction method for the acute treatment of open tibia fractures with bone and soft-tissue loss. DESIGN: Patients were selected for bifocal compression-distraction (shortening and lengthening) who had open tibia fractures with bone and soft-tissue loss and a Mangled Extremity Severe Score of 6 and below indicating good leg viability. PATIENTS: Bifocal compression-distraction osteogenesis using the Ilizarov type circular external fixator was applied to 24 patients with 14 grade IIIA and 10 grade IIIB open tibia fractures with bone and soft-tissue loss. Mean age of the patients was 30.6 years (range 18-53). The mean bone defect was 5 cm (range 3-8.5). The mean soft tissue defect was 2.5 x 3.5 (1 x 2-10 x 5) cm. INTERVENTIONS: Acute shortening at the fracture site was done for patients with bone defects up to 3 cm to achieve apposition of bone ends. Gradual shortening at a rate of 2 mm/d was done for patients who had bone defects more than 3 cm. Leg length discrepancy was overcome by lengthening at the same time through a corticotomy at a proximal or distal level depending on fracture localization, until there was equalization of leg lengths. RESULTS: Mean follow-up period was 30 months (range 18-60). Mean bone healing time was 7.5 months (range 4-11). The mean time in external fixation was 7.1 months (range 3-10), and the average external fixator index was 1.4 months/cm. Results were evaluated using the Paley bone and functional assessment scores. The bone assessment results were excellent in 21 and good in 3 patients. Functional assessment scores were excellent in 19, good in 4, and fair in 1 patient. Pin site infections were present in 10.7% of the pin sites. There were 52 complications in 24 patients, for a complication rate per patient of 2.08. Of the complications, 48.1% were problems (minor complications), 38.5% obstacles (major complications requiring a surgical solution), and 13.4% sequelae (true complications). Minor complications included soft tissue inflammation and infection, translation/angulation, and delayed maturation during distraction and transient knee contracture and loss of motion. All grade 1 and 2 soft tissue inflammations and infections healed with nonoperative therapy. Major complications included pin tract infection and reinfection, equinus deformity, frame failure, and premature consolidation, all of which required additional surgery to correct the problem. Sequelae included leg length discrepancy, loss of knee/ankle range of motion, knee flexion contracture, malalignment, and chronic osteomyelitis. CONCLUSION: Bifocal compression-distraction osteogenesis is a safe, reliable, and largely successful method for the acute treatment of open tibia fractures with bone and soft-tissue loss. Further nonoperative or operative treatment can correct most complications.

Adolescent↗
PubMed1999

Primary leiomyosarcoma of the mandible in a 7-year-old girl: report of a case and review of the literature.

Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly in the oral cavity because of the paucity of smooth muscle in that location. To the best of our knowledge, only 10 cases of leiomyosarcoma primary to the jawbones have been reported in the English language literature. We report the first pediatric case of leiomyosarcoma arising from the mandible. Facial asymmetry and swelling were accompanied by a rapidly growing exophytic soft tissue mass that caused buccal displacement of the mandibular left permanent first molar. The lesion, observed radiographically as an extensive ill-defined area of osteolytic alveolar destruction, perforated the lingual cortex, displaced the inferior alveolar nerve canal inferiorly, and produced a "floating-in-air" appearance of the first molar. Diagnosis of leiomyosarcoma was made after initial incisional biopsy of the lesion. A 5-cm segmental mandibulectomy and supraomohyoid neck dissection were followed by reconstruction with a dynamic mandibular reconstruction plate and placement of a multidimensional mandibular distraction device in a transport rectangle of bone to promote bifocal distraction osteogenesis. Forty millimeters of distraction (the technical limit of the device) were performed; this was followed by terminal iliac crest bone grafting. Seventeen months after the definitive surgical procedure, the patient remains free of disease.

Actins↗
PubMed1998

[Callus distraction of femur and tibia. Experiences with the mono-fixateur--indications for procedural changes].

In a 4-year period, 18 patients underwent callus distraction of the femur or tibia with the use of a unilateral external fixator. Twelve patients had post-traumatic bone loss resulting from complex lower-limb fractures. The bony defect was located in the tibia in 11 cases and in the femur in one case. All patients had major associated soft-tissue lesions. The length of the bony defect averaged 6.25 cm. Eight fractures were infected at the beginning of treatment. Six other patients underwent callus distraction for reasons of limb shortening. Five femora and one tibia were lengthened. The average increase in length was 6.5 cm. There were no fixator-related complications during distraction. The rate for the lengthening and consolidation phase was 49 days for 1 cm of length. Complications consisted of angulatory deformities in 6 cases, infections in four cases, fractures at the docking site in four cases and a fracture of the callotasis in one case. Nine patients underwent reosteosynthesis: planned secondary nailing after callus distraction was carried out in six patients. Three patients underwent plating at the docking site. The follow-up examination after bone transport showed a good-to-excellent outcome in 7 out of 11 patients. The outcome was satisfactory in 4 cases. Results after limb lengthening were good to excellent in all cases. The unilateral external fixator is, in our opinion, a convenient stabilization device and permits appropriate bone transportation for distraction osteogenesis. Alignment control during distraction, however, was difficult to manage in some cases. At the time of docking, reosteosynthesis by intramedullary nailing represents a viable alternative for further external fixation if the limb is free of infection.

Adolescent↗
PubMed2006

Morphological features of cartilage observed during mandibular distraction in rabbits.

Ossification during distraction osteogenesis can be classified as intramembranous or endochondral. It is not known whether cartilage in the distraction gap is transformed into new bone. The aim of this study was to investigate the morphological features of ossification in the transition of cartilage to bone during mandibular distraction osteogenesis in a rabbit model. A cortical osteotomy was performed and custom-made devices were applied. Immediately after surgery, the devices were lengthened by 0.25 mm every 12h for up 10 days, during which time four rabbits were killed at 0, 5 and 10 days and examined using histological staining and immunohistochemical methods. Apoptotic cells were identified by an in-situ detection assay for nuclear DNA fragmentation using a modified TUNEL procedure, with several sections analyzed using software for histomorphometric analysis. The results showed that the amount of cartilage in the distraction gap was significantly decreased. The cartilage had ossified in two ways, termed endochondral ossification and transchondroid bone formation.

Alkaline Phosphatase↗
PubMedDate not supplied

Biological reconstruction after excision of juxta-articular osteosarcoma around the knee: a new classification system.

BACKGROUND: A new classification system for juxta-articular osteosarcoma around the knee joint was developed to allow biological reconstructions using distraction osteogenesis or frozen autograft containing tumors treated with liquid nitrogen. Type I: Tumor has metaphyseal extension to a maximum of 2 cm from the epiphyseal cartilage plate. Type II: Tumor extends to at least half the circumference of the epiphyseal cartilage plate. Type III: Extension to the whole circumference of the epiphyseal cartilage plate. Type IV: Tumor extends to part of the epiphysis through any point of the epiphyseal cartilage plate 10 mm from the joint line. Type V: Tumor extends to half or less of the epiphysis. Type VI: Extension of the tumor to more than half of the epiphysis. PATIENTS AND METHODS: Twenty patients with juxta-articular osteosarcoma around the knee joint were treated according to this classification system. The cohort comprised 12 males and 8 females with a mean age of 20 years. The tumors were located in the femur in 12 patients and in the tibia in 8 patients. RESULTS: The tumors were Type II in 1 patient, Type III in 8 patients, Type IV in 2 patients, Type V in 3 patients and Type VI in 6 patients. Reconstruction after tumor excision was performed using distraction osteogenesis in 13 patients and using frozen autografts in 7 patients. The mean follow-up in the series was 54 months, ranging from 5 to 103 months. CONCLUSION: The classification system may act as a guide to appropriate decision-making in cases of juxta-articular osteosarcoma around the knee joint. Biological reconstruction, using distraction osteogenesis or frozen autografts, may yield good functional results without leading to an increase in the incidence of local recurrence.

Adolescent↗
PubMed2005

Linear increase in axial stiffness of regenerate callus during limb lengthening.

Distraction osteogenesis is a powerful tool for addressing segmental defects and limb-length discrepancies. Guidelines for the rate and rhythm of distraction have been described. The possibilities of early consolidation or nonunion threaten clinical success. A quantifiable method for monitoring the distraction gap would be useful. Previous methods to measure regenerate callus stiffness have not gained widespread clinical acceptance, largely because of cumbersome instrumentation. A rabbit tibial lengthening model was used to show the clinical utility of a digital torque wrench in monitoring axial stiffness of the regenerate bone callus during distraction osteogenesis. We confirmed the linear increase in peak torsional stiffness with time, which has been reported by others. This relationship may prove to be a useful clinical adjunct in guiding the rate and rhythm of distraction during limb lengthening.

Animals↗
PubMed1999

Evaluation of the consolidation period during osteodistraction using computed tomography.

The use of distraction osteogenesis offers an alternative approach to the correction of craniofacial deformities. However, little is known with respect to the appropriate length of the consolidation period for the newly formed bone. The objective of this study was to evaluate, by quantitative computed tomography, the regenerate bone produced during osteodistraction of the dog mandible at three different consolidation times. Twelve skeletally mature male beagle dogs were equally separated into three experimental groups. Each dog underwent 10 mm of bilateral distraction osteogenesis to lengthen the mandible. After the distraction period, the bone was allowed to consolidate for 4, 6, or 8 weeks, at which time the animals were sacrificed and the mandibles harvested for computed tomographic imaging. The results demonstrate a significantly lower mean bone density of the regenerate in the 4 week group when compared with either the 6 or 8 week groups (P < .01). There was no significant difference, however, in mean bone density between the 6 and 8 week groups.

Animals↗
PubMed2003

Correlation of immunohistochemical characteristics of the craniomandibular joint with the degree of mandibular lengthening in rabbits.

PURPOSE: This study examined immunohistochemical changes in the craniomandibular joints of rabbits after distraction osteogenesis following mandibular corticotomy. MATERIALS AND METHODS: The experimental animals (n = 8) were divided into 3 groups that underwent 2, 3.5, and 5 mm of unilateral distraction osteogenesis (groups 1, 2, and 3, respectively). After corticotomy of the left mandibular body and a 7-day healing period, a second operation was performed to expose the device. Distraction was then performed at the rate of 0.5 mm/d. A 14-day consolidation period was allowed after the distraction was complete. Changes in cartilage, osteoblast activity, and osteoclast activity were then examined. RESULTS: The differentiation and proliferation of cartilage increased in groups 1 and 2, were highest in group 2, and decreased in group 3. Group 2 also showed the greatest increase in the width of the hypertrophic chondrocyte layer. Relative to the control group, osteoclast activity was only somewhat higher in groups 1 and 2 but was significantly higher in group 3. Osteoblast activity was significantly higher in groups 1 and 2 than in the control group. However, the osteoblast activity in group 3 was slightly lower than that in group 2. At the time of unilateral mandibular distraction, no degenerative changes of the temporomandibular joint were observed in groups 1 or 2, but bone resorption was observed in group 3. CONCLUSIONS: The unilateral mandibular distraction of 2 or 3.5 mm was acceptable in that no degenerative changes of the temporomandibular joint were observed on either the distraction or the nondistraction sides. Five millimeters of distraction might be beyond physiologic limits.

Alkaline Phosphatase↗
PubMed2000

[Callus distraction of the maxilla. Supplement or alternative to advancement osteotomy].

Total or partial relapses after conventional surgical advancement of the maxilla following Le Fort I osteotomy in CLP patients are frequent and major complications. The aim of this investigation was to find out whether the technique of distraction osteogenesis in these patients shows more stability and whether maxillary distraction is able to replace conventional advancement. Maxillary distraction was performed in 12 patients. In two cases, a Delaire mask was used to bring the maxilla forward, ten patients were treated with the extraoral distraction device designed by Polley. In all patients, planned advancement of the maxilla could be achieved; one partial relapse occurred. The results indicate that distraction osteogenesis offers the possibility of advancement of the maxilla with the required stability. The technique presents a major improvement which is achieved with a relatively minor surgical procedure.

Adolescent↗
PubMed1998

The role of latency in mandibular osteodistraction.

Even though osteodistraction has been well established in the extremities, the parameters used in craniofacial distraction have been essentially borrowed from orthopaedic experience. Latency is widely practised but its relevance has not been fully investigated. The purpose of this study was to establish the role of latency in mandibular distraction osteogenesis. Twenty-two growing Wethers sheep were allocated to four experimental groups. Six animals were allocated to each of Groups A, B and C and underwent bilateral mandibular corticotomies and attachment of an external lengthening device. Latent periods of 0, 4 and 7 days respectively were observed prior to beginning distraction. The distraction protocol consisted of a rate of 0.5 mm twice daily for 20 days, followed by a consolidation phase of 20 days after which the sheep were killed. Histology, bone densitometry and 3-point mechanical testing were performed on the harvested mandibles. Group D formed the control group (n = 4). Histologically, the distracted bone exhibited bone formation primarily via intramembranous ossification with scattered islands of cartilage. The regenerated bone had mechanical properties significantly weaker than the undistracted control group (P < 0.05), but between the experimental groups no statistically significant differences were demonstrable either in mechanical strength or DEXA density. These data indicate that a change in latency does not alter the properties of the regenerated bone in mandibular distraction osteogenesis and indeed no latent interval may be necessary at all in craniofacial distraction. This has implications for the duration of device fixation in distraction procedures.

Absorptiometry, Photon↗
PubMed1999

Maxillary distraction in cleft lip palate patients: a review of six cases.

Cleft lip and palate patients can present with a maxillary retrusion with tendency to Class III malocclusion after cleft repair. Maxillary distraction osteogenesis is a technique that provides simultaneous skeletal advancement and expansion of the soft tissues. Six nonsyndromic cleft lip and palate patients, ages 12 to 16 years (mean, 13.8 years), underwent maxillary distraction; four had a unilateral and two a bilateral cleft lip and palate. After an incomplete LeFort I osteotomy; a latency period of 3 days was respected. On Postoperative Day 4, distraction was initiated through anterior traction on a Delaire facial mask using distraction forces of 900 gm. Photographs and lateral cephalometric radiographs were obtained preoperatively and 4 months after distraction. A cephalometric analysis was performed to compare the sagittal dentocraniofacial morphology before and after distraction. The aesthetic improvement obtained by maxillary distraction osteogenesis during the permanent dentition to correct maxillary retrusion in our cleft lip and palate patients was impressive. Skeletal advancement varying from 1 to 3.5 mm (mean, 1.7 mm) was found. However, significant dentoalveolar compensations occurred in three patients. This was due to the dental anchorage of the distraction device and can be avoided only by the use of skeletal fixation.

Adolescent↗
PubMed1999

Mandibular distraction in temporomandibular joint ankylosis.

Condylar damage during childhood can produce ankylosis and alteration of the mandibular growth. In case of unilateral ankylosis occurring in early childhood, a mandibular hypoplasia of the affected side may develop. The patients have limitation of mouth opening, facial asymmetry, and chin deviation toward the affected side. The aims of this study are to show the use of distraction osteogenesis in mandibular hypoplasia associated with ankylosis and to present our experience with a new therapeutic option for the treatment of mandibular hypoplasia with unilateral ankylosis in the childhood consisting of the association of arthroplasty to treat the ankylosis and mandibular distraction to correct the facial asymmetry, both accomplished in the same surgical procedure. From November of 1996 to November of 1997, three male patients aged 2, 7, and 13 years with mandibular hypoplasia and ankylosis were treated by distraction osteogenesis. An arthroplasty consisting of the resection of the ankylotic block and interposition of a temporalis muscle flap, plus coronoidectomy was done in two of them and mandibular distraction was done in all three patients. Articular functional rehabilitation began on the first postoperative day. Mandibular distraction began on the fifth postoperative day with a rate of 1 mm per day, ending when the facial symmetry was achieved. From the first postoperative day, an increase in the mouth opening was achieved; this increase continued until ending the distraction. The average duration of distraction was 22 days. Average duration of consolidation was 6 weeks. Oral opening increased from 10 mm to 35 mm in the 7-year-old patient, from 9 mm to 27 mm in the 2-year-old patient, and from 14 mm to 38 mm in the 13-year-old patient. To date, oral opening and facial symmetry persist. Osseous mandibular distraction together with arthroplasty offers an excellent new alternative for treatment of patients with mandibular hypoplasia and associated ankylosis, with minimal morbidity and complications.

Adolescent↗
PubMed2000

[Clinical evaluation, radiologic and histologic analysis in mandibular alveolar distraction procedures. Preliminary study].

BACKGROUND: Alveolar distraction osteogenesis is a process to form new alveolar bone to correct alveolar deformities in ridge height and width. Aim of this work is to study the bone processes to optimize the implantoprosthetic rehabilitation. METHODS: Alveolar distraction osteogenesis was applied in 7 patients with ridge deformities to obtain the desired ridge augmentation. Clinical and radiological evaluations were performed during the following 12 weeks, before implant insertion. Biopsies at 40, 60 and 88 days were studied after general, specific and histochemical staining of slides; microradiographs were analyzed to evaluate the trabecular bone volume. RESULTS: Forty days after the end of distraction, soft callus shows the start of ossification. Sixty days after the end of distraction, soft callus was widely converted into a network of trabecular woven bone; osteogenic activities were low; trabecular bone volume was about 50%. Eighty-eight days after the end of distraction bone amount appeared reduced, with a more ordered structure, further reduction of bone formation activity, whereas osteoclast erosion was active. CONCLUSIONS: Results show an almost steady-state bone deposition processes 60 days after the end of distraction and a regress with longer time. The results suggest the possibility of an early implant insertion to avoid bone loss due to mechanical unloading.

Adolescent↗
PubMed2001

Mineralization dynamics of regenerate bone during mandibular osteodistraction.

Distraction osteogenesis offers an alternative approach for the correction of craniofacial deformities, yet little substantive data is available regarding mineralization of the forming regenerate. The purpose of this study was to evaluate, by plain film radiography and digital subtraction radiography, the mineralization dynamics of regenerate bone during osteodistraction. Thirteen skeletally mature male beagle dogs underwent 10 mm of bilateral mandibular distraction osteogenesis, at which time the bone was allowed to consolidate for either 4, 6, or 8 weeks. The tissues were then evaluated clinically and radiographically. The results demonstrate that several different types of regenerate are evident during mineralization of the distraction gap. A classification system is presented based on the length, width, and density of the mineralizing regenerate, as well as the presence or absence of an interzone. It appears that important factors for determining regenerate stability are the presence or absence of an interzone, as well as the width of the regenerate relative to the host bone segments. Finally, in cases where an interzone is present, subtraction radiography may provide a means of evaluating the level of mineralization within the interzone as well as the dynamics of mineralization over the course of distraction and consolidation.

Animals↗
PubMed2006

Reconstruction of segmental bone defects due to chronic osteomyelitis with use of an external fixator and an intramedullary nail.

BACKGROUND: Callus distraction over an intramedullary nail is a rarely used technique for the reconstruction of intercalary defects of the femur and tibia after radical débridement of chronic osteomyelitic foci. The aim of this study was to summarize our experience with distraction osteogenesis performed with an external fixator combined with an intramedullary nail for the treatment of bone defects and limb-shortening resulting from radical débridement of chronic osteomyelitis. METHODS: Thirteen patients who ranged in age from eighteen to sixty-three years underwent radical débridement to treat a nonunion associated with chronic osteomyelitis of the tibia (seven patients) and femur (six patients). The lesions were classified, according to the Cierny-Mader classification system, as type IVA (nine) and type IVB (four). The resulting segmental defects and any limb-length discrepancy were then reconstructed with use of distraction osteogenesis over an intramedullary nail. Two patients required a local gastrocnemius flap. Free nonvascularized fibular grafts were added to the distraction site for augmentation of a femoral defect at the time of external fixator removal and locking of the nail in two patients. At the time of the latest follow-up, functional and radiographic results were evaluated with use of the criteria of Paley et al. RESULTS: The mean size of the defect was 10 cm (range, 6 to 13 cm) in the femur and 7 cm (range, 5 to 10 cm) in the tibia. The mean external fixator index was 13.5 days per centimeter, the consolidation index was 31.7 days/cm, and the mean time to union at the docking site was nine months (range, five to sixteen months). At a mean follow-up of 47.3 months, eleven of the thirteen patients had an excellent result in terms of both bone and functional assessment. There were two recurrences of infection necessitating nail removal. These patients underwent revision with an Ilizarov fixator. Subsequently, the infection was controlled and the nonunions healed. CONCLUSIONS: This combined method may prove to be an improvement on the classic techniques for the treatment of a nonunion of a long bone associated with chronic osteomyelitis, in terms of external fixation period and consolidation index. The earlier removal of the external fixator is associated with increased patient comfort, a decreased complication rate, and a convenient and rapid rehabilitation.

Adolescent↗
PubMed1998

Biomechanical considerations of mandibular lengthening and widening by gradual distraction using a computer model.

PURPOSE: Experience using distraction osteogenesis for limb lengthening has shown the importance of appliance orientation. Although successful results of mandibular lengthening using osteodistraction have been reported, optimal orientation of the distractors relative to the mandible has not been determined. The purpose of this study was to evaluate the biomechanical effects of linear distractors placed parallel to the body of the mandible or parallel to the axis of distraction. MATERIALS AND METHODS: A two-dimensional model of the human mandible was generated for computer simulation of mandibular osteodistraction. Linear distractors were then analyzed based on their orientation, either parallel to the body of the mandible or parallel to the axis of distraction. In addition, two types of distraction osteogenesis procedures for mandibular reconstruction were analyzed: 1) bilateral mandibular lengthening, and 2) bilateral mandibular lengthening in combination with midline mandibular widening. RESULTS: Distractors oriented parallel to the body of the mandible caused a lateral displacement of the posterior components of the distraction devices and a reduction of the midline distraction gap during mandibular lengthening. These effects were eliminated when the device was oriented parallel to the axis of distraction. Midline symphyseal widening created axial rotation of the mandibular condyles regardless of the orientation of the distractors. CONCLUSIONS: Distraction appliances must be oriented parallel to the axis of distraction to prevent adverse biomechanical effects during bilateral mandibular lengthening. Additional ramus osteotomies, using hinged devices for angular correction, may be necessary to compensate for rotational movements of the mandibular condyles secondary to midline osteodistraction.

Biomechanical Phenomena↗
PubMed2000

Gene expression of TGF-beta, TGF-beta receptor, and extracellular matrix proteins during membranous bone healing in rats.

Poorly healing mandibular fractures and osteotomies can be troublesome complications of craniomaxillofacial trauma and reconstructive surgery. Gene therapy may offer ways of enhancing bone formation by altering the expression of desired growth factors and extracellular matrix molecules. The elucidation of suitable candidate genes for therapeutic intervention necessitates investigation of the endogenously expressed patterns of growth factors during normal (i.e., successful) fracture repair. Transforming growth factor beta1 (TGF-beta1), its receptor (Tbeta-RII), and the extracellular matrix proteins osteocalcin and type I collagen are thought to be important in long-bone (endochondral) formation, fracture healing, and osteoblast proliferation. However, the spatial and temporal expression patterns of these molecules during membranous bone repair remain unknown. In this study, 24 adult rats underwent mandibular osteotomy with rigid external fixation. In addition, four identically treated rats that underwent sham operation (i.e., no osteotomy) were used as controls. Four experimental animals were then killed at each time point (3, 5, 7, 9, 23, and 37 days after the procedure) to examine gene expression of TGF-beta1 and Tbeta-RII, osteocalcin, and type I collagen. Northern blot analysis was used to compare gene expression of these molecules in experimental animals with that in control animals (i.e., nonosteotomized; n = 4). In addition, TGF-beta1 and T-RII proteins were immunolocalized in an additional group of nine animals killed on postoperative days 3, 7, and 37. The results of Northern blot analysis demonstrated a moderate increase (1.7 times) in TGF-beta1 expression 7 days postoperatively; TGF-beta1 expression returned thereafter to near baseline levels. Tbeta-RII mRNA expression was downregulated shortly after osteotomy but then increased, reaching a peak of 1.8 times the baseline level on postoperative day 9. Osteocalcin mRNA expression was dramatically downregulated shortly after osteotomy and remained low during the early phases of fracture repair. Osteocalcin expression trended slowly upward as healing continued, reaching peak expression by day 37 (1.7 times the control level). In contrast, collagen type IalphaI mRNA expression was acutely downregulated shortly after osteotomy, peaked on postoperative days 5, and then decreased at later time points. Histologic samples from animals killed 3 days after osteotomy demonstrated TGF-beta1 protein localized to inflammatory cells and extracellular matrix within the fracture gap, periosteum, and peripheral soft tissues. On postoperative day 7, TGF-beta1 staining was predominantly localized to the osteotomized bone edges, periosteum, surrounding soft tissues, and residual inflammatory cells. By postoperative day 37, complete bony healing was observed, and TGF-beta1 staining was localized to the newly formed bone matrix and areas of remodeling. On postoperative day 3, Tbeta-RII immunostaining localized to inflammatory cells within the fracture gap, periosteal cells, and surrounding soft tissues. By day 7, Tbeta-RII staining localized to osteoblasts of the fracture gap but was most intense within osteoblasts and mesenchymal cells of the osteotomized bone edges. On postoperative day 37, Tbeta-RII protein was seen in osteocytes, osteoblasts, and the newly formed periosteum in the remodeling bone. These observations agree with those of previous in vivo studies of endochondral bone formation, growth, and healing. In addition, these results implicate TGF-beta1 biological activity in the regulation of osteoblast migration, differentiation, and proliferation during mandibular fracture repair. Furthermore, comparison of these data with gene expression during mandibular distraction osteogenesis may provide useful insights into the treatment of poorly healing fractures because distraction osteogenesis has been shown to be effective in the management of these difficult clinical cases.

Animals↗
PubMed1989

Ilizarov treatment of tibial nonunions with bone loss.

Twenty-five patients aged 19-62 years were treated for tibial nonunions (22 atrophic, three hypertrophic) with bone loss (1-23 cm, mean 6.2 cm) by the Ilizarov technique and fixator. Thirteen had chronic osteomyelitis, 19 had a limb-length discrepancy (2-11 cm), 12 had a bony defect (1-16 cm), and 13 had a deformity. Six had a bone defect with no shortening, 13 had shortening with no defect, and six had both a bone defect and shortening. Nonunion, bone defects, limb shortening, and deformity can all be addressed simultaneously with the Ilizarov apparatus. Bone defects were closed from within without bone grafts by the Ilizarov bone transport technique of sliding a bone fragment internally, producing distraction osteogenesis behind it until the defect is bridged (internal lengthening). Length was reestablished by distraction of a percutaneous corticotomy or through compression and subsequent distraction of the pseudarthrosis site (external lengthening). Distraction osteogenesis resulting from both processes obviated the need for a bone graft in every case. Deformity was corrected by means of hinges on the apparatus. Infection was treated by radical resection of the necrotic bone and internal lengthening to regenerate the excised bone. Union was achieved in all cases. The mean time to union was 13.6 months, but it was only 10.6 months if the time taken for unsuccessful compression-distraction of the nonunion is eliminated from the calculation. The bone results were excellent in 18 cases, good in five, and fair in two based on union in all cases, persistent infection in three, deformity in four, and limb shortening in one. The functional results were excellent in 16 cases, good in seven, fair in one, and poor in one based on return to work and daily activities in all cases, limp in four cases, equinus deformity in five cases, dystrophy in four cases, pain in four cases, and voluntary amputation for neurogenic pain in one case.

Adult↗