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At least 37 records · Page 2Linked to original sources
PubMed2001

Ilizarov hybrid external fixation for fractures of the distal radius: Part II. Internal fixation versus Ilizarov hybrid external fixation: Stability as assessed by cadaveric simulated motion testing.

The in vitro stability of an Ilizarov hybrid external fixator was compared with that of a dorsal 3.5-mm AO T-plate in 8 unpaired, fresh-frozen upper extremities. A specially designed testing device that used computer-controlled pneumatic actuators was used to simulate active finger, wrist, and forearm motions by applying loads to relevant tendons. A comminuted extra-articular distal radius fracture was modelled using a dorsally based wedge osteotomy. Fracture stability was assessed using an electromagnetic tracking device to measure motion across the fracture site after randomized application of the plate and the hybrid fixator. During simulated finger and wrist motions with the forearm pronated or supinated, motion of the distal fragment with the hybrid fixator applied was comparable to or statistically less than with the AO plate applied. During simulated forearm rotation, the stability provided by the 2 fixation types was similar, although the plate allowed statistically less radial-ulnar deviation of the fragment. In this model of a 2-part extra-articular distal radius fracture, the clinically meaningful stability of the Ilizarov hybrid external fixator was comparable to that of the dorsal AO plate.

Aged↗
PubMed2000

Extramedullary fixation implants for extracapsular hip fractures.

BACKGROUND: Extramedullary fixation of hip fractures refers to the application of a plate and screws to the lateral side of the proximal femur. OBJECTIVES: To compare different types of extramedullary fixation implants for the surgical treatment of extracapsular hip fracture in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group trials register and reference lists of relevant articles. Date of the most recent search: March 1998. SELECTION CRITERIA: All randomised or quasi-randomised trials comparing extramedullary implants used in the fixation of extracapsular hip fracture in adults. DATA COLLECTION AND ANALYSIS: All three reviewers independently assessed trial quality, using a ten item scale, and extracted data. Additional information was sought from all trialists. Wherever appropriate and possible, results of outcome measures were pooled by comparison. MAIN RESULTS: The methodological quality of all six included trials was poor and in no trial was there clear concealment of allocation. Three trials involving 355 patients compared a fixed nail plate (Jewett or McLaughlin) with the sliding hip screw (SHS). The limited data presented indicated an increased risk of fixation failure outcomes for fixed nail plates. One trial involving 233 patients compared the RAB plate (a fixed angle blade plate with an oblique connecting strut) with the SHS. In this trial both implants had a high incidence of fixation failure. There was a tendency to a lower incidence of cut-out, re-operation, fixation failure, leg shortening, varus deformity and mortality for the RAB plate. None of the differences in these outcomes were statistically significant. One trial involving 100 patients compared the Pugh nail and the SHS. There was no significant difference between implants for the outcome measures reported. One trial involving 176 patients with 182 fractures, compared the Medoff plate with the SHS. A significantly higher mean operative blood loss and longer mean operative time were reported for the Medoff plate. There was however a tendency to a lower risk of fixation failure for unstable trochanteric fractures fixed with the Medoff plate. REVIEWER'S CONCLUSIONS: The fixed nail plate was demonstrated to have to an increased risk of implant breakage and fixation failure in comparison to the SHS. Although the lack of evidence from randomised trials for other outcomes means that a firm conclusion of overall superiority of the SHS cannot be made, the increased fixation failure rate is a major consideration and indicates that the SHS is preferable. Insufficient information is available to draw firm conclusions of the clinical significance of differences between the SHS and either the RAB plate, the Pugh nail or the Medoff plate.

Bone Plates↗
PubMed2006

Extramedullary fixation implants and external fixators for extracapsular hip fractures in adults.

BACKGROUND: Extramedullary fixation of hip fractures involves the application of a plate and screws to the lateral side of the proximal femur. In external fixators, the stabilising component is held outside the thigh by pins or screws driven into the bone. OBJECTIVES: To compare different types of extramedullary fixation implants and external fixators for fixing extracapsular hip fracture in adults. SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (July 2005), various other databases, conference proceedings and reference lists. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials comparing extramedullary implants or external fixators for fixing extracapsular hip fracture in adults. DATA COLLECTION AND ANALYSIS: Two authors independently selected trials, assessed trial quality and extracted data. Data were pooled where appropriate. MAIN RESULTS: The 14 included trials tested seven comparisons in a total of 2222 mainly female and older participants. All trials had methodological flaws that may affect the validity of their results. Three trials comparing a fixed nail plate (Jewett or McLaughlin) with the sliding hip screw (SHS) found an increased risk of fixation failure for fixed nail plates. The two trials comparing the Resistance Augmented Bateaux (RAB) plate with the SHS had contrasting results, notably in terms of operative complications, fixation failure and anatomical restoration. One trial comparing the Pugh nail and the SHS found no significant difference between implants. Two trials compared the Medoff plate with the SHS. One trial reported higher blood losses and longer operation times for the Medoff plate. There was a lower risk of fixation failure with the Medoff plate for unstable trochanteric fractures. Two trials compared the Medoff plate with three different screw-plate systems. There were no statistically significant differences in outcome for trochanteric fractures. For subtrochanteric fractures, there was a lower fixation failure rate for the Medoff plate, but no evidence for differences in longer-term outcomes. Two trials comparing the Gotfried percutaneous plate with a SHS found a reduced blood loss with the Gotfried plate. A higher intra-operative fixation failure rate of the Gotfried plate may indicate some restriction to its use. Two trials found less operative trauma for external fixation when compared with the SHS. Final outcome appeared similar. AUTHORS' CONCLUSIONS: The markedly increased fixation failure rate of fixed nail plates compared with the SHS is a major consideration and thus the SHS appears preferable. There was insufficient evidence from other comparisons to draw definite conclusions.

Bone Plates↗
PubMed2002

A biomechanical comparison of fragment-specific fixation and augmented external fixation for intra-articular distal radius fractures.

The biomechanical stability of an internal fixation system that uses low-profile modular implants to stabilize individual fracture components was studied in a validated cadaver fracture model that incorporated physiologic muscle forces and wrist motion. Fragment-specific fixation with immediate range of motion was compared with static augmented external fixation in simulated, unstable 3- and 4-part intra-articular distal radius fractures (n = 20). Fixation was applied and specimens were loaded via their major wrist tendons. Because the wrist joint was not constrained in the internal fixation group, full wrist motion occurred during load application in these specimens. A 3-dimensional motion tracking system calculated individual fracture fragment motion in both groups. In the 3-part fracture pattern fragment-specific fixation showed comparable stability to static augmented external fixation despite the full wrist range of motion that occurred during application of load in these specimens. In the 4-part fracture pattern fragment-specific fixation was shown to be significantly more stable when compared with static augmented external fixation in 4 of 6 axes of motion. Our findings confirm the stability of this low-profile plating system and support the consideration of early wrist motion when treating complex, intra-articular distal radius fractures with fragment-specific fixation.

Biomechanical Phenomena↗
PubMed1995

The use of combination internal fixation and hybrid external fixation in severe proximal tibia fractures.

Forty-eight patients with 50 severe fractures of the proximal tibia were followed prospectively for 2-4 years (mean 2.7 years) to evaluate the use of limited internal fixation combined with external fixation in the treatment of these injuries. There were 27 men and 21 women ranging in age from 20 to 74 years. Fractures were classified according to the A0 system (Mast J, Ganz R, Jacob R: Planning and reduction technique in fracture surgery. Berlin, Springer-Verlag, 1989), which included 5 A3, 6 C1, 16 C2, and 23 C3 fractures. All patients in this series healed; 48 fractures healed in an average of 12 weeks without subsequent surgery. There were two (4%) nonunions requiring bone graft. The average hospital special surgery knee score was 90 (68-100). Grading criteria for anatomical outcome revealed there were 17 (34%) excellent results, 24 (48%) good results, 6 (12%) fair results, and 3 (6%) poor results. In conclusion, this treatment method is associated with a high percentage of good and excellent results. Combined internal and external fixation combines the advantages of anatomic, stable fixation with less soft-tissue dissection and eliminates the need for large implants.

Adult↗
PubMed2006

[Distal intraarticular humerus fractures in elderly patients. Treatment with combined percutaneous screw fixation and an external fixator].

BACKGROUND: Intra-articular distal humerus fractures are relatively uncommon. Due to osteoporosis in elderly patients, stable fixation still remains a problem despite new implants providing angular stability. MATERIAL AND METHODS: The treatment of choice is open reduction and plate fixation requiring an extended approach with olecranon osteotomy often combined with additional postoperative immobilisation in a long arm cast. We describe a technique using closed reduction and percutaneous osteosynthesis with cannulated screws combined with external fixation. Morbidity due to surgical exposure and potential risks are diminished while functional results are comparable to open reduction and internal fixation . In contrast to plasters or casts, the use of an external fixator allows stable and safety protection of the elbow joint, preserving wrist function as well as forearm rotation and increasing the patient's comfort during immobilisation. RESULTS: We have used this technique on ten patients aged 76.2 years (range 67-88 years). According to the AO classification, there were three B-1/B-2 fractures, four C-1 and three C-2/C-3 fractures without severe comminution. The duration of external fixation was 6.3 weeks (range 4-8 weeks) before fracture union was achieved. This allows the initiation of physiotherapy and motion of the elbow. There was only one revision caused by the necessary replacement of an aseptic loosened Schanz screw. At follow-up 3 months postoperatively, the range of motion of the elbow was 95 degrees (65 degrees-105 degrees ), average extension 25 degrees (10 degrees-35 degrees ) and mean flexion was 115 degrees (100 degrees-120 degrees ) with all patients exhibiting full pro/supination.

Aged↗
PubMed1990

[Method of fracture fixation using external fixation devices].

An improvement of the results of treatment can be reached, beside respecting the indication of external fixateurs, with correct tactics of the treatment. Because of the disadvantages of the fixateur externe, we strive to restrict their use, to the time by all means necessary, and if possible to use other methods of fixation. This is motivated especially by the effect on fracture healing and the hindering of the movements and activity of the patient.

Biomechanical Phenomena↗
PubMed1993

Mechanical performance of Ilizarov circular external fixators in comparison with other external fixators.

The fundamental difference of the Ilizarov fixator is the type of pins used for bone fixation, i.e., Kirschner wires 1.5 mm and 1.8 mm in diameter, pretensioned from 50 to 130 kg before being affixed to the rings that are connected and fixed by threaded rods. The mechanical characteristics of external fixators may influence the biologic environment at the fracture site and ultimately decide the outcome of a surgical procedure. Thus, knowledge of the mechanical properties of the Ilizarov fixator is essential to a surgeon using it in clinical practice. The main objective of this study was to quantitate the mechanical behavior of the standard Ilizarov fixator under different loading conditions and fixator frame/wire configurations. The fixator was found to have a nonlinear stiffness behavior under axial compression. The nonlinearity in axial stiffness also varied with wire pretension. Such characteristics, however, were not as pronounced under torsion and bending loads within the test range studied. Besides the wire pretension, the most important factor affecting the structural stiffness of the Ilizarov device was the diameter of the wire. Offset bone position provided greater stiffness in loads up to 45 kg in axial compression, in torsion up to 5 degrees of rotation, and in the final loading range under bending. Fixators with wires crossing at 45 degrees had significantly greater stiffness in torsion as compared with 90 degrees crossing wires, but the opposite was true in axial compression. Torsional stiffness increased significantly under coupled axial compression applied through the bone ends. All four-point bending tests demonstrated two distinct stiffness curves that were probably due to slippage of the bone model on the wires. This information should help to understand the mechanical behavior of the Ilizarov device and thereby improve its clinical performance.

Bone Lengthening↗
PubMed2005

Outcome after foot and ankle deformity correction using circular external fixation.

BACKGROUND: External fixation is the method of choice for correction of chronic severe foot and ankle deformities. We report our experience and outcomes of circular external fixation. METHODS: Fifty-five patients (60 feet) were treated with circular external fixation. The mean age at surgery was 36 (range 16 to 65) years. The mean followup was 4.4 (range 1 to 10) years. The mean time spent in external fixation was 2.1 (range 1 to 12) months. RESULTS: There were six excellent, 35 good, eight fair, and six poor results, five of which had below knee amputations. All the patients who had an amputation were treated for infected nonunion of the ankle. CONCLUSION: Circular external fixation was found to be an effective method for treating a variety of complex foot and ankle problems. The complications were more common in patients with infected nonunions.

Adolescent↗
PubMedDate not supplied

[A new test procedure to examine the stability of external fixation clamps--demonstrated with the Stuhler-Heise external fixation system (author's transl)].

Experimental investigation of stabilty for examination of the efficiency of external fixation clamps required different testing procedures and measuring arrangementsz which is due to variant assessment parameters and natures of load. Here is a description of a measuring equipment which could be applied for all important cases of load. In relation to the entire experimental arrangement it also enables the testing of all external fixation assemblies. Deviations of the poroximal fragment caused by loading, are considered as assessment parameters of the stability. This measuring set was practically applied on simulated defect fractures, stabilized by the Stuhler-Heise external fixation system. During a combined bending strain the stability degree of various two-dimensional as well as three-dimensional external fixation clamps for application on tibias was determined.

Bone Nails↗
PubMed2003

External fixation of the foot and ankle. Elective indications and techniques for external fixation in the midfoot.

Although external fixation is widely used for treatment of fractures, limb deformities, and bone lengthening; use of external devices is still evolving. Elective cases for treatment of the midfoot and published research on external fixation specifically for surgical treatment of midfoot pain and deformity are scarce. Indications for elective external fixation in the midfoot are limited because rigid internal fixation in this area is relatively easy and successful. This article discusses podiatric conditions that can be treated advantageously by external fixation when elective surgery is done. The article also describes methods of external fixation appropriate for podiatric surgical reconstruction in patients with these conditions.

Arthrodesis↗
PubMed1997

Evaluation of a simple and low-cost external fixator.

Simple external fixation is becoming ever more popular for the treatment of fractures. Current commercially available external fixation devices are complex and expensive, affecting management of injuries in less developed countries. In this study, a new simple and low-cost external fixator called the AG (Alinoor-Goh) fixator, is evaluated biomechanically by direct comparison with a commercially available fixator device (AO). Four modes of loading were applied to each of the fixators: axial compression, anterior-posterior bending, medial-lateral bending, and torsion. The loads were applied directly onto a fractured-bone model made of perspex, which was immobilized by the fixator through six Schanz pins. From this, stiffness values were obtained by plotting load versus displacement. The results from the mechanical testing indicated that in axial compression the AG fixator stiffness was 55.7 +/- 0.197 N/mm (AO fixator was 57.7 +/- 0.186 N/mm); for anterior-posterior bending it was 56.8 +/- 0.153 N/mm (57.4 +/- 0.134 N/mm); for medial-lateral bending it was 11.4 +/- 0.036 N/mm (11.6 +/- 0.053 N/mm); and for torsion it was 1.16 +/- 0.002 N.mm/degree (1.16+/- 0.003 N.mm/degree). No significant difference was found in the stiffness of AG and AO fixators, under all modes of loading. A further comparison in terms of overall design, versatility in application and cost shows the AG fixator to be a viable, inexpensive option for the treatment of long-bone fractures.

Costs and Cost Analysis↗
PubMed1999

Effect of pin location on stability of pelvic external fixation.

Pelvic external fixators allow two locations of pin purchase: anterosuperior (into the iliac crest) and anteroinferior (into the supraacetabular dense bone, between the anterior superior and anterior inferior iliac spine). The purpose of this study was to compare the stability of these two methods of fixation on Tile Type B1 (open book) and C (unstable) pelvic injuries. Five unembalmed cadaveric pelves (mean age, 68 years; four males and one female) were loaded vertically in a servohydraulic testing machine in a standing posture. The AO tubular system and Orthofix were used. On each pelvis, a Type B1 injury was simulated. Each external fixator was applied in each location in random order. Cyclic loads were applied through the sacral body to a maximum of approximately 200 N while force and displacement of the pelvic ring were recorded digitally. Sacroiliac joint motion was quantified tridimensionally with displacement transducers, mounted on the sacrum and contacting a target fixed to the posterior superior iliac spine. A Type C injury was created and augmented with two iliosacral lag screws, and the tests were repeated. For the Type B1 injuries with anteroinferior pin purchase, the mean stiffness was 201.2 N/mm for the AO frame and 203.2 N/mm for the Orthofix. For the anterosuperior frames the mean stiffness was 143.9 N/mm for the AO frame and 163.3 N/mm for the Orthofix. For Type B1 and Type C injuries, the anteroinferior location of pin purchase resulted in significantly reduced sacroiliac joint separation. There were no significant differences between the frame types. Dissection of the preinserted anatomic specimen revealed no evidence of injury to the lateral femoral cutaneous nerve after blunt dissection and drilling with protective drill sleeves. It is concluded that the anteroinferior location of external fixation pins is a safe technique with the potential for increased stability of fixation.

Acetabulum↗
PubMed1984

[Epiphyseal fixation with an external fixator. Biomechanical and clinical study].

Fifty one fractures of an epiphysis were treated by fixation using a new external fixator. The stability of the fixation was compared with that obtained by other types of fixator. The basis of the technique was the insertion of five pins into the epiphysis and of a series of pins in the diaphysis. Fixation between the epiphyseal and diaphyseal pins was achieved by three bars. The results obtained in 38 cases, half of them being at the proximal end of the tibia were analysed and were found to be encouraging. Only three had to be grafted secondarily. There was a low number of mal-unions. The main advantage of this method was to allow early mobilisation of the joint. The risk of sepsis did not give rise to concern provided that the rods do not cross the joint.

Biomechanical Phenomena↗
PubMed2000

External fixation of distal radial fractures: 3 or 5 weeks of external fixation.

In a retrospective study we compare the functional and radiographical results of 2 groups of patients with unstable distal radial fractures treated with external fixation. In Group 1, 20 patients with 21 fractures were treated with external fixation for 3 weeks followed by a cast for 2 weeks. In Group 2, 16 patients were treated with external fixation for 5 weeks. The functional outcome was good in both treatment groups with no significant difference between the results in the two groups. Radiologically, Group I had less radial shortening than Group II, but there was no difference in the degree of dorsal angulation.

Aged↗