Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “External Fixators”

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.

At least 901 records · Page 50Linked to original sources

Treatment of the sequelae of primary pathology of the hip by correction osteotomy and femoral lengthening using a combined external fixator.

It is not an exceptional event to observe the sequelae of primary pathology of the hip in young patients that, as such, are not of the ideal age for replacement surgery. Moreover, one must not overlook the difficulties involved in replacement surgery for the treatment of inveterate modifications in the normal hip anatomy. Often, among the sequelae of primary pathology of the hip, deformities of the lower limb must also be included, associated or consequent, which also need treatment. For these reasons, the authors, in three selected cases, used a combined external fixator (circular and lateral) by means of which they were at the same time able to correct the axial deformity (with a support osteotomy), and the residual hypometria (with femoral lengthening). Osteotomy plus lengthening, using an external fixator, avoid hypometria of the limb and deformity in valgus of the knee, and allow for results which would otherwise not be obtained with replacement surgery alone.

Adult↗

[The open femoral fracture in war--173 external fixators applied to the femur (Afghanistan war)].

During the three years 1988 through 1990, more than 700 external skeletal fixations (AO/ASIF Tubular System) were utilized at the ICRC Hospital for Afghan War Wounded in Peshawar, Pakistan, 173 of which were for femoral fractures. 13% of the fractures were open grade II, and 71% open grade III, mostly due to high velocity gunshot or shrapnel injuries. Usually, the external fixator was left in place until consolidation of the fracture. The average time of external fixation was 128 days. Three major groups of complications have been observed: fracture complications, implant complications, and residual loss of function of the knee joint, probably the most significant permanent complication to the patient. In order to improve the functional results in treating open fractures of the femur, three measures are recommended: unilateral frame with posterolateral insertion of Schanz screws, postoperative positioning of the patient with 90 degrees of flexion of hip and knee joints and mobilization of the patient as soon as possible (on the first or second postoperative day).

Afghanistan↗

A comparison of hydroxyapatite-coated, titanium-coated, and uncoated tapered external-fixation pins. An in vivo study in sheep.

Three types of surfaces for external fixation pins were compared. One hundred and eight stainless-steel tapered 5/6-millimeter pins were divided into three groups: thirty-six pins remained uncoated (Group A), thirty-six were plasma-sprayed with hydroxyapatite (Group B), and thirty-six were plasma-sprayed with titanium (Group C). The pins were implanted in the left tibia of eighteen sheep, with each sheep receiving six pins from the same group. A unilateral fixator then was assembled on the pins. The medial aspect of the mid-part of the tibial diaphysis was exposed, and a five-millimeter-long cylinder of bone was removed so that load would be borne by the bone-pin interfaces. Six weeks after the procedure, radiographs demonstrated rarefaction of twenty-nine pin tracks in Group A, fifteen in Group B, and thirty in Group C (p = 0.021 for Group A compared with Group B and p = 0.016 for Group B compared with Group C). The mean final insertion torque (and standard deviation) was 4360+/-1050 newton-millimeters in Group A, 3420+/-676 newton-millimeters in Group B, and 3740+/-643 newton-millimeters in Group C. With the numbers available, no significant differences could be detected among these values. The mean extraction torque was 253+/-175 newton-millimeters in Group A, 3360+/-1260 newton-millimeters in Group B, and 1720+/-1030 newton-millimeters in Group C (p = 0.002 for Group A compared with Group B, p = 0.017 for Group A compared with Group C, and p = 0.03 for Group B compared with Group C). The extraction torque was significantly lower than the corresponding insertion torque in both Group A (p < 0.001) and Group C (p = 0.003); no significant difference could be found, with the numbers available, in Group B (hydroxyapatite-coated pins). At sixty times magnification, direct contact was seen along a mean of 16+/-9 per cent of the bone-pin interface in Group A, 30+/-12 per cent of the interface in Group B, and 28+/-15 per cent of the interface in Group C (p = 0.042 for Group A compared with Group C). However, at 10,000 times magnification, direct bone-pin contact was found only in Group B.

Animals↗

A device for improved reduction of tibial fractures treated with external fixation.

A widely used method of treatment for unstable tibial shaft fractures is unilateral external fixation. The majority of fixators act as three distinct devices: an intra-operative reduction device, a device to maintain fracture alignment during healing and an aid to healing by allowing movement at the fracture site. Conventional operative techniques require the surgeon to manipulate a number of degrees of freedom at once, making reduction of the fracture difficult, and results in the fixator being out of alignment with the long axis of the bone. An operative method has been developed that separates reduction and fixation. A dedicated device has been designed to improve the per-operative control of fracture fragments during fracture reduction. The device has been used in clinical trials for the reduction of 22 diaphyseal tibial fractures. Compared with previous operative techniques there has been a saving of 53 per cent in fracture reduction time and an overall saving of 10 per cent in operating time. Fracture alignment has been improved compared with reductions achieved with a fixator which potentially improves healing and lowers the rate of malunion. In each case the fixator has been applied in alignment with the bone, improving dynamization and reducing the likelihood of malunion due to fixator cam slippage.

Biomechanical Phenomena↗

Articulated external fixation of the ankle: minimizing motion resistance by accurate axis alignment.

This study describes how an optimal single hinge axis position can be established for the application of articulated external fixation to the ankle joint. By deliberately introducing various amounts of relative mal-alignment between the optimal talocrural joint axis and the actual fixator hinge axis, it was possible to measure the corresponding amounts of additional resistance to joint motion. In a cadaveric study of six ankle specimens, we determined the instant axis of rotation of the talocrural joint from 3-D kinematic data. acquired by an electromagnetic motion tracking system. For each specimen, an optimal fixator hinge position was calculated from these motion data. Compared to the intact natural joint, aligning the fixator along the optimized axis position caused a moderate increase in energy (0.14 J) needed to rotate the ankle through a prescribed plantar/dorsiflexion range. However, malpositioning the hinge by 10 mm caused more than five times that amount of increase in motion resistance. While articulated external fixation with limited internal fixation can establish a favorable environment for the repair of severe injuries such as tibial pilon fractures, the large additional resistance to motion accompanying a malpositioned fixator axis suggests the development of untoward intra-articular forces that could act to disturb fragment alignment.

Ankle↗

Knee arthrodesis using circular external fixator in the treatment of infected knee prosthesis: case report.

A patient (68 years old and male) underwent total knee replacement because of arthrosis, but he subsequently had infection due to a wound problem. Although he underwent early debridement, antibiotherapy, and soft-tissue operation, treatment failed because of improper soft-tissue coverage and progression of the infection. Therefore, the prosthesis was removed and a spacer with antibiotic was placed, in order to provide soft-tissue coverage and to eradicate infection. After 2 months, the patient underwent knee arthrodesis using a circular external fixator to achieve a stable lower extremity and to facilitate return to activities of daily living. We obtained knee fusion at 4 months without any requirement for secondary procedure of soft tissue and bone graft. There was no major complication. Arthrodesis with circular external fixator is a reliable and successive method that should be preferred for the treatment of infected knee replacement.

Aged↗

"Ring fixator" for treatment of lower leg fractures. A review of 30 cases treated by a new external fixation system.

Besides generally known therapeutic practice, indications can be discovered and more easily evaluated by using a "Ring Fixator". Applications include the following: (1) stage fractures of the tibia, (2) stabilisation of fractures of polytraumatized patients with no need for prior anatomical reduction and (3) closed lower limb fractures with severe soft tissue lesions. The major advantages of the "Ring Fixator" include the following: possible unlimited correction of primary and secondary dislocations without needing to transpose implanted Steinmann-pins or Schanz' screw; compatibility with ASIF external fixation systems for supplementary use of "Ring Fixator" elements; possible management of secondary dislocations and variable placement of pins or screws for subsequent wound debridement and muscle flap transposition. Results so far obtained using the "Ring Fixation" are illustrated by clinical examples.

Adult↗

Trapezio-lunate external fixation for scaphoid fractures. An experimental and clinical study.

Trapezio-lunate external fixation for scaphoid fractures has been investigated experimentally and clinically. Six below-elbow fresh amputation specimens in which proximal, waist and distal scaphoid fractures were created, displaced, reduced and externally fixed were used for an experimental study and after 10,000 extension-flexion movements of the wrist, no displacement was observed. A strain-gauge study confirmed the strains at the fracture site. Seven patients were treated in this way. No immobilization was necessary and all patients returned to their regular employment within 3 days and all fractures were united without displacement. The technique overcomes certain disadvantages of plaster fixation and internal fixation of scaphoid fractures.

Adult↗

Influence of bone quality on the strength of internal and external fixation of tibial plateau fractures.

We studied the influence of different parameters of bone quality on the fixation strength of bicondylar tibial plateau fractures and examined the relationship between these parameters. Bone quality was measured in the plateau of 16 cadaveric tibias using three modalities: dual-energy X-ray absorptiometry (DXA), peripheral quantitative computer tomography (pQCT), and spectral analysis of digitized radiographs (SADR). The tibias were divided into two groups by the median bone mineral density (BMD) and randomized to receive either dual plating or external fixator for the stabilization of a standardized bicondylar tibial fracture. The fixed fractures were subjected to axial compression until failure. DXA BMD correlated most significantly with the failure load (r>or=0.79, p<0.001), followed by the pQCT parameters of cancellous bone (0.52>or=r>or=0.73, p<0.01). Similar strong correlations were also evident in both fixation methods. For parameters derived from SADR, only those including both longitudinal and transverse trabecular orientations had modest correlation with the fixation strength (0.53>or=r>or=0.71, p<0.01). The failure loads of the two fixation techniques were not significantly different (mean+/-SD=3522+/-1386 N and 3710+/-1356 N, respectively, p=0.78). However, BMD in the dual-plating group influenced the failure load significantly (p=0.03), whereas in the external fixation group this was less evident (p=0.100). The majority of bone quality parameters that correlated with fixation strength were also strongly correlated with each other, particularly the BMDs measured by DXA and pQCT. This is the first study that relates fixation strength of bicondylar tibial plateau fractures to bone quality assessed at the same anatomical site. BMD around the fracture site had the best correlation with the failure load regardless of the fixation technique. The two fixation methods tested performed equally well, and the choice between them depends on the soft tissue condition and surgeon preference.

Biomechanical Phenomena↗

Source of the slippage in the universal joints of the Hoffmann external fixator.

An investigation was conducted to determine what improvements in the resistance to slippage could be obtained in selected interfaces (rod/clip torsional, cheek/bowl and cheek/clip) of the Hoffmann external fixator. The modification involved changing the standard wing-nut clamp for a bolt with a thread of 7 mm and a 1 mm pitch and placing an FAG 28-303 thrust-bearing (needle roller and cage assembly) between the bolt and the cheek. The results showed a significant improvement in the slippage values of all interfaces; increases of approximately six times were obtained at all torque values of the wing-nut clamp or fastener tested. Such improvements would markedly increase the reliability of external fixation systems and thus reduce the incidence of loss-of-reduction of fracture due to slippage of the universal joint.

Equipment Failure↗

[Echography in the monitoring of bone callus in fractures treated with external fixation].

The authors report on the use of US in the evaluation of osteogenesis in the fractures treated with external fixation. From April 1991 to October 1992, fifty patients with diaphyseal fractures were submitted to real-time US examinations, with 7.5-5 MHz probes, mainly on longitudinal scans. The evolutive stage of bone callus was studied and, in the presence of periosteal bone bridge, its length and height were measured. In all but 4 patients US, unlike radiology, allowed the signs of osteogenesis to be detected as early as from day 10 on and the peculiar bilobate pattern known as primary callus response was clearly demonstrated. This stage is of fundamental importance because it allows, when periosteal callus is absent, direct intervention on the dynamic process, by varying the external fixation-bone complex so as to make it more flexible. In 80% of patients periosteal apposition was observed on day 24. Delayed osteogenesis depended on the patient's age and on fracture type. Such pathologic signs as hyperstimuli, pseudoarthrosis and/or hematoma persistence were quite unfrequent findings. Even though the study of US semiology is still in progress, our results are in substantial agreement with literature data and emphasize the role of US in the early evaluation of the bone callus and its evolution.

Adolescent↗

[Value of external fixation in proximal tibial fractures].

PURPOSE OF THE STUDY: This study was a retrospective analysis of 39 proximal metaphyseal tibial fractures treated by Orthofix fixator in two trauma departments. MATERIAL AND METHOD: There were 28 men and 10 women with a mean age of 49.5 years. 13 pedestrians were stroked by a car and 18 had a traffic accident on a motorcycle. In 27 cases, the fracture was open with following Cauchoix grading: 15 types 2, 6 types 1 and 6 types 3. All fractures were partially or totally included in the proximal epiphyseal square of the AO system. 14 fractures were metaphyseal, 13 diaphyso-metaphyseal and 12 had an articular irradiation. All external fixations were performed using the Orthofix device, with image intensification. A partial weight bearing was allowed for 2.4 months as an average and full weight bearing at mean 3.7 months. 7 skin grafts, 2 micro surgical (latissimus dorsi) and 2 local flaps were necessary. RESULTS: In 3 patients this technique failed. 3 patients had an autologous bone graft at the metaphyseal and 2 at the diaphyseal fracture site. 30 patients healed without other procedure after an average delay of 5.5 months. During the healing and weight bearing time, 6 frontal deformities appeared and 5 flexion contractures were not reoperated. With a minimum follow up of one year (mean 3 years) 22 fractures had no deformity, 8 had a valgus deformity (5 degrees to 10 degrees) and 3 a varus deformity (6 to 17 degrees). For the 25 patients with an isolated proximal tibial fracture, 11 (44%) had an excellent functional result (no pain, full range knee motion, normal daily activity); 12 (48%) had a good result (episodic pain, minimally knee discomfort, flexion limitation). DISCUSSION: Orthofix fixator appear to be a good solution for comminuted fractures. These fractures have anatomical and epidemiological particularities. AO classification system is not useful; a new one is proposed. External fixator must be placed meticulously after closed fracture reduction.

Accidents, Traffic↗

Bladder entrapment after external fixation of traumatic pubic diastasis: importance of follow-up computed tomography in establishing prompt diagnosis.

A 30-year-old male was an unrestrained driver in a high-speed motor vehicle crash. On presentation, the patient was profoundly hypotensive with multiple injuries, including a 20-cm-deep perineal laceration with avulsion of the rectum, a diffusely tender abdomen, an unstable open-book pelvic fracture, and multiple rib fractures. Blood noted at the urethral meatus prompted a retrograde urethrogram and cystogram, which were within normal limits. A Foley catheter was placed with the return of clear urine. Closed reduction and external fixation of the pelvic fracture were performed emergently without difficulty. Postoperative computed tomography of the abdomen and pelvis revealed a retrovesical pelvic hematoma and entrapment of the bladder in the reduced pubic symphysis diastasis. Lower abdominal exploration revealed an intact bladder without evidence of gross bladder wall injury. On release of the external fixator, the bladder was easily reduced into the normal retropubic location. Definitive internal fixation of the pubic diastasis was performed. No urologic sequelae were noted postoperatively.

Adult↗

Control of motion of tibial fractures with use of a functional brace or an external fixator. A study of cadavera with use of a magnetic motion sensor.

A computer-linked magnetic motion transducer was used to monitor and record the six components of motion of the bone fragments in eight cadaveric tibiae in which a simulated, oblique fracture of the middle of the shaft had been stabilized with a functional brace. The limbs were mounted in a servo-hydraulic testing frame, and a cyclic load of 150 newtons was applied along the axis of the tibia. Motion sensors, attached to each side of the fracture, measured and displayed the values of the three translations (axial, anterior-posterior, and medial-lateral), the axial rotation, and the two angulations (anterior-posterior and varus-valgus) as they occurred. Although only an axial load was applied, the off-axis motions were comparable in magnitude with the motion along the axis. The elastic (recoverable) translations of the fragments ranged from 0.5 to 1.9 millimeters, about four to ten times larger than the corresponding motions that were recorded in an earlier study of such fractures that had been stabilized with two types of external fixators. The recoverable rotation and angulations of the fragments of the limbs in the functional brace ranged from 0.7 to 1.2 degrees, about ten times those recorded when the external fixators were used.

Braces↗

[One- or two-step management (with external fixator) of severe pilon-tibial fractures].

Pilon tibiale fractures with significant joint involvement (AO-classification B2/3 and C2/3) are considered one of the most unfavourable injuries of the lower extremity. It was possible for follow-up examinations to be performed on 50 patients with this injury pattern from the years 1984 to 1988. Primary plate osteosynthesis is primary blamed for causing a high infection rate. Remaining functional losses, uneven joints, defective positionings and early arthrosis are not avoidable with either a one step or a two step approach. The infection rate could be significantly lowered through a two step approach with primary stabilization through an external fixator, without having to accept further disadvantages. An early change of procedure in suitable cases between the second and third week guarantees an internal osteosynthesis with the best possible anatomic reposition of articular surface and axes. In chosen cases an end treatment is possible with an external fixator. The road is open for a primary arthrodesis of irreparably damaged articular surfaces.

Ankle Injuries↗

Transcutaneous reduction and external fixation of displaced fractures of the proximal humerus. A controlled clinical trial.

A consecutive series of 31 displaced fractures of the proximal humerus were randomly selected for treatment either by closed manipulation or by transcutaneous reduction and external fixation. Follow-up assessed the quality of reduction and healing as well as the functional outcome. The external fixation method gave better reduction, safer healing and superior function.

Adult↗

[Unilateral external fixator combined with simple internal fixation for severe open tibia-fibular fracture].

OBJECTIVE: To improve the treatment for severe open tibia-fibular fracture. METHODS: From 1994 to 2000, 146 patients with severe open tibia-fibular fracture were treated. According to Gustilo classification, all patients were of type III. Among them, 96 patients belonged to III A, 36 III B, and 18 III C. One hundred and eight patients were male and 38 female, aged from 11 to 68 years, with an average of 31. All patients were treated with unilateral external fixator combined with simple internal fixation (general screw or Kirschner wire). Thirty patients were treated with secondary flap operation. Among them, 19 patients received pedicle gastrocnemius muscle flaps, 9 free vastus lateralis muscle flaps, and 2 free latissimus dorsi muscle flaps. RESULTS: Three patients of type IIIB were subjected to amputation because of advanced age and associated cerebral or thoraco-abdominal injury. Five patients of type III C had amputation because of insufficient postoperative blood supply and necrosis. The rupture of other 138 patients was well reduced, and firmly fixed. They were followed up for 6 months-6 years, with an average of 2.5 years. The average time of fracture-union was 27 weeks, and the average time for removal of fixtors was 28 weeks. The motion of knee joint ranged from 0 to 120 degree in 110 patients; from 0 to 100 degrees in 25, and from 0 to 90 degrees. The motion of ankle joint was approximately normal. CONCLUSIONS: For patients with severe open tibia-fibular fracture, comprehensive analysis should be made for preservation of the wounded limb or amputation as for elderly patients with vessel-nerve injury or with cerebral- thoracoabdominal injury, emergency amputation should be done. Unilateral external fixator combined with simple internal fixation (general screw or Kirschner wire) for severe open tibia-fibular fracture is advantageous for a simple and reliable fixation. It is less traumatic.

Adolescent↗

Severe intracranial injury from a fall in the halo external fixator.

This is a report of a rheumatoid arthritis patient after atlantoaxial stabilization and halo external fixator immobilization who presented with intracranial injury after an accidental fall. Global aphasia and an impaired consciousness resulted from a cerebral hemorrhagic contusion below an impressed bone chip at the left posterior halo-pin site. Cranial penetration of a halo pin has been previously reported; however, brain injury associated with it has not. Since there is a considerable risk of falls in the elderly and in patients with myelopathic gait disturbances, this rare but potentially hazardous complication should be kept in mind during the halo vest fixation.

Accidental Falls↗