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At least 19 recordsLinked to original sources

[Use of palacos in osteosynthesis for the connection of fragments (combined internal fixation)].

Internal fixations have become a frequent approach in surgery due to the profound studies dealing with biomechanical details of fractures and quality of metal devices. In the beginning, it seemed practically possible to manage easily, almost all the fractures by using various internal fixation devices excluding, naturally, those which have retained or shall retain probably some indications of further cure by closed methods. Moreover, certain doubts remain still open, particularly for the reason whether all internal fixations have been sufficiently rigid and if so, shall it be indispensable to count on the introduction of additional materials in order to strenghten these fractures. The outcome of the daily practice 1rd traumatho to approach the use of the bone cement, initially to help the fixation of new joints. Later the use of the bone cement was applied for the shaft and pathological fractures in combination with autogenous cancellous bone. Thus, the new notion was borne in traumathology which in the form of combined internal fixation has become a familiar term throughout the professional literature. Cases of the experience gained and this particular approache in surgery will be a subject of the report.

Adult

Experimental studies on the use of a cushioned plate for internal fixation.

Internal fixation is widely used in the operative treatment of fractures, but various problems, such as local osteoporosis, may occur when living bone is fixed with a rigid metal plate. We propose a new method of immobilisation, which we have termed "cushioned plate fixation", in an attempt to solve some of these problems. Cushioned plate fixation involves a silicone rubber cushion placed between the steel plate and the bone. On the basis of data obtained from animal experiments in vivo and mechanical tests in vitro, we conclude that the cushion is effective in preventing osteoporosis without decreasing the strength of fracture fixation. We believe that this method might improve the mechanical biocompatibility of plate fixation.

Animals

Comminuted fractures of the basilar joint of the thumb: combined treatment by external fixation, limited internal fixation, and bone grafting.

Displaced, comminuted fractures of the thumb carpometacarpal joint were treated by intermetacarpal external fixation, anatomic reduction of the joint surfaces, bone grafting and adjunctive internal fixation in thirteen patients. Retrospectively, at an average follow-up time of 35 months, nine patients showed a good result and one patient had a fair result. All fractures had united without secondary displacement, but focal irregularities of the joint surface were commonly seen. As compared with the uninvolved side, axial rotation averaged 79%, radial abduction 89%, key pinch 88%, and grip strength 81%.

Adolescent

Complications of orthognathic surgery: a comparison between wire fixation and rigid internal fixation.

This retrospective review compares the results of using rigid internal fixation (RIF) and wire fixation for orthognathic surgery patients. The records of two groups of demographically similar patients who underwent comparable surgery, performed by the same four attending surgeons at the same institutions during the same time period (1983 to 1986), were evaluated for complications and unanticipated treatment results. The most striking finding of this study is the general similarity between the two groups. However, differences in frequency of excessive weight loss and persistent restriction of mandibular opening suggest a benefit from early mobility of the mandible that comes with RIF. Because there was no concomitant increase in complications or unexpected results of treatment, the introduction of RIF for orthognathic surgery may offer patients some potential advantages.

Humans

Simultaneous maxillary and mandibular orthognathic surgery stabilized by rigid internal fixation.

Rigid internal fixation was used successfully in 111 consecutive cases in which both the maxilla and the mandible were mobilized simultaneously. The use of rigid fixation allowed for early mobilization of the mandible, which facilitated resumption of orthodontic therapy after surgery. The favorable short-term results achieved indicate the need to study the long-term stability of the technique.

Bone Plates

Medial external fixation with lateral plate internal fixation in metaphyseal tibia fractures. A report of eight cases associated with severe soft-tissue injury.

Eight patients with unstable fractures involving the articular surface and metaphyseal-diaphyseal bone of the proximal or distal tibia associated with severe soft-tissue injury or compounding wound were treated with irrigation, debridement, tetanus inoculation, antibiotic prophylaxis, and combined internal fixation with one-half frame external skeletal fixation for neutralization. All patients were followed to complete healing and functional restoration of the extremity. All fractures healed, but one superficial and one deep infection occurred. All patients achieved at least 110 degrees of knee motion. This method should be considered in unstable metaphyseal and articular tibia fractures not adequately stabilized with a lateral plate in which use of an additional medial plate is required for stability, but contraindicated because of the status of the soft tissues or extensive comminution of the bone.

Accidents, Traffic

Internal fixation of pelvic ring fractures.

The orthopedic care of unstable pelvic fractures requires reduction and stabilization in order to promote union in a satisfactory position and provide a satisfactory clinical result. The results of three treatment techniques, skeletal traction and/or pelvic sling, anterior frame external fixation, and internal fixation, were evaluated over a four-year period.

Adolescent

Rigid internal fixation for fractures involving tooth-bearing maxillary segments.

Fracture dislocations of the middle third of the face usually involve a complex combination of the three types of fractures initially described by LeFort. Treatment of these injuries requires a six- to eight-week period of intermaxillary fixation, unless rigid internal fixation devices (plates and screws) are used to stabilize the fractures. However, rigid fixation carries the risk of producing a malunion and serious malocclusion if not performed correctly. A review of 22 patients with complex LeFort fractures treated with rigid fixation revealed that the only absolute contraindication to its use is difficulty in interdigitating the maxillary and mandibular teeth in a passive fashion at the time of fracture reduction. Rigid internal fixation should therefore be considered as an alternative treatment for most fractures of the middle third of the face.

Fracture Fixation, Internal

Update-1988. Current status of internal fixation of thoracolumbar fractures.

Rigid internal fixation has become the preferred method of treatment for unstable thoracolumbar fractures in most American spine centers. In most cases, posterior instrumentation alone is adequate, but occasionally an anterior procedure is necessary. A number of internal fixation devices are now available to the orthopaedic surgeon. Controversy exists regarding the number of levels that need to instrumented and the optimal form of internal fixation.

Adult

The AO spinal internal fixator.

The AO spinal internal fixation system uses 5.0 mm diameter transpedicular Schanz screws with 7.0 mm diameter fully threaded stainless steel rods. Originally developed for the treatment of thoracolumbar and lumbar spine fractures, it can be used for a variety of spinal disorders. A prospective study has been carried out, and the first 48 patients have been reviewed. The results for those patients with fractures are excellent. In burst fractures, it has been possible to decompress the canal and restore lordosis. In only half of the cases of spondylolisthesis has it been possible to improve the degree of slip. The fixator has provided rigid stabilization for a variety of other spinal problems.

Adolescent

Mechanical stability and post-traumatic osteitis: an experimental evaluation of the relation between infection of bone and internal fixation.

Stable and unstable internal fixation of fractures was performed in rabbits. After inoculation with Staphylococcus aureus, clinically manifest osteitis occurred only in the very unstable fractures. Abscesses, sinuses and sequestra developed in 45 per cent of the unstable fractures, whereas clinically manifest osteitis did not occur after rigid fixation. With rigid fixation there was no significant difference in the time to bony union between the infected and uninfected fractures. It seems that the development of osteitis and the healing of a fracture are both related to the degree of rigidity, but remain independent of each other. The significance of these findings in the management of posttraumatic osteitis is discussed.

Animals

Management of mandibular trauma with rigid internal fixation.

The use of rigid internal fixation has become an acceptable method for the treatment of fractures and continuity defects of the mandible. This technique has a wide variety of applications, including stabilization of mandibular segments for the application of bone grafts. The primary advantage of rigid fixation is that it obviates the need for maxillomandibular fixation associated with the treatment of mandibular trauma by traditional methods. This article reviews twenty cases in which rigid internal fixation was used for the treatment of fractures and continuity defects of the mandible. In only one case was early removal of the implant necessary as a result of infection.

Adult

[Cross stabilization of the internal fixator of the spine].

The "Internal Fixator" for stabilizing the dorso-lumbar spine represents an effective and meanwhile established device to neutralize flexion-bending and sagittal shearing forces. Because of the possible movement of the Schanz' screws in the bone and within the connection clamps, this device does not withstand torsional and frontal plane shearing forces after postinjury or postlaminectomy instability. Therefore, a cross-link device, adaptable to the "Internal Fixator" has been developed. Biomechanical testing against torsion and frontal plane bending moments have shown very low stability resulting in lateral displacement of the fixation device without cross-linking. The diagonal bracing with two wire cerclages does not significantly increase the stability. The recently developed cantilever cross-link device completes the two longitudinal bars to a frame construction and increases therefore the torsional and frontal plane stability for over 70%. This supplementary device is easy to apply to the "Internal Fixator" and has been successful in clinical practise.

Biomechanical Phenomena

Biomechanical evaluation of a biodegradable composite as an adjunct to internal fixation of proximal femur fractures.

Internal fixation of comminuted unstable fractures of the severely osteoporotic proximal femur is sometimes supplemented with polymethyl-methacrylate (PMMA). We here report an in vitro biomechanical evaluation of a biodegradable particulate composite that might be used for similar purposes. The composite includes a matrix phase consisting of a hydrolyzable prepolymer [polypropylene fumarate (PPF)] cross-linked with methacrylate monomer, and a particulate phase consisting of tricalcium phosphate and calcium carbonate. We implanted dynamic hip screws in 22 cadaveric proximal femora and measured the yield load for an oblique force applied to the femoral head. The hip screws were then reinforced with either PMMA or the PPF composite and tested again. On the basis of analysis of variance, the average increases in yield load for PMMA and PPF reinforcement of 1,750 and 1,130 N were statistically significant (p less than 0.00005), suggesting that both materials enhance congruence between implant and bone and thereby increase the projected load-bearing area of the implant. The increase in yield force with PMMA was slightly higher than the increase with PPF (p less than 0.05), but both values after reinforcement were close (3,790 +/- 561 N for PMMA vs. 3,240 +/- 669 N for PPF). If we can demonstrate that appropriate rates of degradation, bony ingrowth, and static and fatigue properties can be achieved in vivo with this system, our data suggest that this PPF composite may have potential as an adjunct to the internal fixation of unstable fractures of the osteoporotic hip.

Aged

Fixation of mandibular fractures: a comparative analysis of rigid internal fixation and standard fixation techniques.

This study used a prospective design to compare standard therapy (closed or open reduction with 4 weeks of maxillomandibular fixation) to rigid internal fixation (RIF) for the treatment of mandibular fractures. Ninety-two patients with 143 fractures were evaluated and treated. There was no statistically significant difference in the treatment results between the two groups, despite a bias in the distribution of study variables that favored the standard therapy.

Adult

[Transversal fracture of the patella: experimental evaluation of the Lotke and Ecker method of internal fixation].

Four different methods of internal fixation of transverse fractures of the patella were experimentally evaluated in eight cadaver knees: circumferential wiring, tension band cerclage, cerclage over Kirschner wires and the Lotke's method. Linear and angular displacements were accurately measured by means of a micrometer while actively extending the knee from 90 degrees of flexion to full extension. Circumferential wiring gave the highest displacements, up to 25 mm at 30 degrees of flexion on average. Tension band cerclage showed much better results but the greatest stability was obtained with the cerclage over Kirschner wires and with the Lotke's technique which yielded displacements of less than 1 mm. These last two methods combine the tension band principle and transosseous fixation, which are both essential to obtain a stable fixation.

Evaluation Studies as Topic

Experimental study on internal fixation of femoral neck fractures.

The relative strength and the failure mode of internal fixation by multiple pinning and nailing was investigated on 35 specimens. Internal fixation consisted of 3, 5 and 7 Knowles pins, a Smith-Petersen nail or a sliding nail plate. The strength of a specimen with a triflanged nail is only half of that with multiple Knowles pins. There is no significant difference in strength of 3, 5, or 7 pin specimens. The strength of an internal fixation with a sliding nail plate is not superior to the strength of multiple pinning. The mode of failure for the different types of internal fixation is primarily a crush fracture of the supporting trabecular bone at the femoral neck with downward and outward migration of the pins or nail. Except with the fixation with 3 pins where an initial bending could be observed, failure is not a plastic deformation of the internal fixation device.

Bone Nails

Reconstruction of the lumbar spine using AO DCP plate internal fixation.

Augmentation of lumbar spine fusion with internal fixation using pedicle screw systems has gained wide currency because it offers rigid stabilization to foster fusion healing. The AO DCP plate has been employed in Europe as a spinal implant with pedicle fixation using 6.5 mm, full-threaded cancellous bone screws with success. This report details the experience of using this device for lumbar spine fusion in a series of 46 North American patients with a mean follow-up of 1.25 years (range 1-2.5 years). Thirty-one patients had had prior lumbar spine surgery with poor outcomes, and 15 had had no prior surgery. All were treated surgically for lumbar degenerative disease with canal decompression, internal fixation with AO plates, and fusion with autologous bone grafting posterolaterally. Complications included two early and one delayed wound infection; five cases of screw loosening; three cases of screw breakage; and three cases of screw impingement upon a nerve. Results of surgery in 17 patients with failed interbody fusion included good to excellent pain relief in 59%, and solid fusion in 76%. In 14 patients with failed posterior surgery the good to excellent pain relief rate was 79%, and the fusion rate was 86%. In 15 patients undergoing primary surgery there was 89% good to excellent pain relief and a solid fusion rate of 87%. The benefits accruing from augmentation of the fusion with internal fixation using AO DCP plates are positive and justify its continued use. Complications encountered in the early experience have been significantly reduced in subsequent series, indicating the existence of a "learning curve" effect which would mandate specific training of spinal surgeons in the technique.

Bone Plates