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International Orthopaedics May 2023Infection at the pin site remains the most common complication of external fixators (EFs). It is known that hydroxyapatite (HA)-coated pins increase bone adhesion and... (Clinical Trial)
Clinical Trial
PURPOSE
Infection at the pin site remains the most common complication of external fixators (EFs). It is known that hydroxyapatite (HA)-coated pins increase bone adhesion and may lead to reduced rates of reported infections. The present study compares the rates of pin track infection associated with stainless steel and HA-coated pins.
METHODS
This is a prospective, multicenter, nonrandomized, comparative intervention study among patients undergoing surgical treatment with EFs of any type between April 2018 and October 2021. Patients were followed up until the removal of the EF, or the end of the study period (ranging from 1 to 27.6 months). The definition of pin track infection was based upon the Maz-Oxford-Nuffield (MON) pin infection grading system.
RESULTS
Overall, 132 patients undergoing external fixation surgery were included. Of these, 94 (71.2%) were male, with a mean age of 36.9 years (SD ± 18.9). Infection of any type (score > 1) was observed in 63 (47.7%) patients. Coated and uncoated-pin track-infection occurred in 45.7% and 48.5% of patients, respectively (P= 0.0887). The probability of developing infection (defined as a score ≥ 2) adjusted for comorbidities and follow-up time was not statistically higher among those who received uncoated pins compared to those who received pins coated with HA (odds ratio (OR) = 1.56, 95% confidence interval (95% CI): 0.67-3.67, p <0.05).
CONCLUSION
In the present study, the external fixator pin infection rates were similar when using HA coating and standard steel pins.
Topics: Humans; Male; Adult; Female; Durapatite; External Fixators; Prospective Studies; Stainless Steel; Fracture Fixation; Bone Nails
PubMed: 36773051
DOI: 10.1007/s00264-023-05717-w -
Journal of Orthopaedics and... Sep 2016The management of displaced supracondylar fracture of the humerus with closed reduction and percutaneous pin fixation is the most widely accepted method of treatment,... (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND
The management of displaced supracondylar fracture of the humerus with closed reduction and percutaneous pin fixation is the most widely accepted method of treatment, but controversy continues regarding the pin fixation techniques. A prospective randomized controlled study was undertaken to compare the stability, functional outcome and iatrogenic ulnar nerve injury between lateral pin fixation and medial-lateral pin fixation.
MATERIAL AND METHOD
Sixty-two patients with Gartland type III supracondylar fracture of the humerus were randomized into two groups-lateral pin fixation (n = 31) and medial-lateral pin fixation (n = 31). Primary assessment was performed for major loss of reduction and iatrogenic ulnar nerve injury. Secondary assessment included clinical outcome, elbow range of motion, radiographic measurements, Flynn grade, and complications.
RESULTS
There were two (6.5 %) iatrogenic ulnar nerve injury cases in the medial-lateral entry group and two (6.5 %) cases with mild loss of reduction in the lateral entry group. No major loss of reduction was observed in either of the groups. There was no statistically significant difference in change of Baumann angle, metaphyseal-diaphyseal angle, Flynn grade, carrying angle, and the total elbow range of motion (P < 0.05) between the two groups.
CONCLUSIONS
Lateral pin fixation offers similar functional and radiological outcome and almost equal mechanical stability compared with medial-lateral pinning without the risk of iatrogenic ulnar nerve injury. LEVEL OF EVIDENCE [OCEBM 2011]: Level 2.
Topics: Bone Nails; Child; Female; Fracture Fixation, Intramedullary; Humans; Humeral Fractures; Iatrogenic Disease; Male; Postoperative Complications; Prospective Studies; Single-Blind Method; Treatment Outcome; Ulnar Nerve
PubMed: 27312248
DOI: 10.1007/s10195-016-0410-2 -
Zhongguo Xiu Fu Chong Jian Wai Ke Za... Oct 2019To summarize the evolving concept and research progress on stability reconstruction in the surgical treatment of intertrochanteric fracture.
OBJECTIVE
To summarize the evolving concept and research progress on stability reconstruction in the surgical treatment of intertrochanteric fracture.
METHODS
Related literature and author's own experience concerning the surgical treatment of intertrochanteric fracture were reviewed and analyzed in terms of fracture pathoanatomy, stable and unstable pattern, adequate and in-adequate reduction, primary and secondary stability, postoperative stability evaluation, and early weight-bearing.
RESULTS
Intertrochanteric fracture occur at the translational area of cervico-trochanteric junction, which has a nature tendency to varus instability. Fracture reduction quality is the paramount factor and is evaluated by two views, the anteroposterior and lateral Garden alignment and cortex apposition between the head-neck fragment and the femoral shaft. Rather than the posteromedial lesser trochanteric frag ment, the cortical support concept (positive, neutral, negative) emphasizes the reduction of anteromedial cortex to a nonanatomic positive apposition or an "anatomic" neutral apposition in intraoperative fluoroscopy. Postoperative radiographic stability score provides a quantitative assessment for early weight-bearing standing and walking. However, some fractures may lose cortical contact and buttress (negative) during the process of postoperative telescoping and secondary stability. Further studies are needed to elucidate the risk factors such as tilting, swing or rotation of the head-neck fragment, and propose new preventive methods.
CONCLUSION
Stability reconstruction of intertrochanteric fracture requires adequate fracture reduction with Garden alignment and anteromedial cortical support apposition, and reliable sustainment by internal fixation implants. Early weight-bearing standing and walking is safe in patients with perfect postoperative stability score.
Topics: Bone Nails; Fracture Fixation, Internal; Hip Fractures; Humans; Retrospective Studies; Treatment Outcome
PubMed: 31544426
DOI: 10.7507/1002-1892.201904148 -
Orthopaedics & Traumatology, Surgery &... Dec 2022The purpose of this study was to examine the effect of insertion angles on the pullout strength of connected pins using a synthetic model simulating a hand bone.
OBJECTIVE
The purpose of this study was to examine the effect of insertion angles on the pullout strength of connected pins using a synthetic model simulating a hand bone.
MATERIAL AND METHODS
The material consisted of Sawbones® (20 mm×20 mm × 60 mm), fixation pins secured to a connecting rod much like an external fixator, an electric drill (speed 1,290 rpm) and a tensile testing machine. The Sawbones® were drilled with different pin diameters (1.2 mm, 1.5 mm, and 1.8 mm) and insertion angles (100°, 110° and 120°). A vertical displacement of 1 mm/min was applied until the pins were extracted (maximum force).
RESULTS
The pullout strength increased with the insertion angle of the connected pins. It also increased with their diameter. Regardless of the pin diameter, the load-displacement curve during the pullout test had 4 sections (peak 1, ascending slope, peak 2, descending slope) that corresponded to the combined frictional force and contact force between the pins and Sawbones®.
DISCUSSION
Our study findings showed that, theoretically, for wrist or hand fractures treated with connected pins, the larger the diameter and insertion angle, the better the mechanical holding power of the pins.
LEVEL OF EVIDENCE
I, experimental study.
Topics: Humans; Hand; Bone Nails; External Fixators; Fractures, Bone; Friction; Biomechanical Phenomena
PubMed: 36126870
DOI: 10.1016/j.otsr.2022.103411 -
Hand (New York, N.Y.) Mar 2023Unstable extra-articular proximal phalanx fractures are common injuries to the hand that are often treated by closed reduction and percutaneous pinning. Fracture-induced... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Unstable extra-articular proximal phalanx fractures are common injuries to the hand that are often treated by closed reduction and percutaneous pinning. Fracture-induced shortening of the proximal phalanx leads to an extensor lag at the proximal interphalangeal joint. We describe a biomechanical study in cadaver hands to compare the ability of each of three different pin configurations to resist shortening in unstable fractures.
METHODS
Seventeen fresh frozen hands were disarticulated at the proximal ends of the metacarpals. The second, third, and fourth proximal phalanges were tested. A 5-mm section of bone was resected from the mid-shaft of proximal phalanx to simulate an unstable fracture. Three techniques were employed and randomized for each finger: transmetacarpophalangeal joint pinning using 1 or 2 Kirschner wires (K-wires) and periarticular cross pinning using 2 K-wires. Compressive axial loads and energy at 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm of subsidence were examined.
RESULTS
The forces and energy required to shorten the finger for each amount of subsidence were similar for all 3 pinning techniques and for all 3 finger types. Greater amounts of shortening were found to require larger forces.
CONCLUSION
Closed reduction and percutaneous pinning using any of the presented techniques is an adequate method of treatment for unstable proximal phalanx fractures. All of the techniques were equivalent in their ability to resist axial loading, regardless of the complexity of technique, the number of pins used, or finger that was pinned.
Topics: Humans; Bone Nails; Bone Wires; Fracture Fixation, Intramedullary; Fractures, Bone; Range of Motion, Articular
PubMed: 34105379
DOI: 10.1177/15589447211017224 -
Journal of Feline Medicine and Surgery Jul 2019Periarticular stifle fractures are uncommon but challenging injuries to treat. There may be concurrent damage to the ligaments and stabilising structures of the stifle...
PRACTICAL RELEVANCE
Periarticular stifle fractures are uncommon but challenging injuries to treat. There may be concurrent damage to the ligaments and stabilising structures of the stifle joint itself, which should also be evaluated (see Part 1 of this article series). Improved knowledge of the fixation options and biomechanical challenges of these injuries will aid clinical decision-making and effective repair.
CLINICAL CHALLENGES
Due to their nature, periarticular fractures may have small juxta-articular fragments, which require additional thought to address during stabilisation. In juvenile animals, these fractures typically involve the physis and often can be managed with cross pin fixation. In adult cats, locking fixation, specialised plates or external skeletal fixators can be utilised to address the juxta-articular fragments. Readers should also be aware of patellar fracture and dental anomaly syndrome (PADS), where cats develop insufficiency fractures affecting the patella and proximal tibia. A careful oral examination should be performed in affected patients, as these cats may have persistent deciduous teeth. Close attention should be paid to preoperative radiographs for evidence of chronicity of the injury including sclerosis of the patella, remodelling and blunting of the fracture lines.
AIMS
The aims of the article are to review the current literature surrounding periarticular fractures of the stifle joint and to summarise the diagnosis, treatment, outcome and complications of each fracture type. As well as discussing general fracture fixation and biomechanical principles applicable to both dogs and cats, information is provided on specific issues facing cats, such as PADS.
EVIDENCE BASE
Published data is limited, with reports including only a small number of cats. The information and recommendations in this article have therefore been drawn from a combination of the available literature and the authors' clinical experience.
Topics: Animals; Bone Nails; Cats; External Fixators; Female; Fracture Fixation; Intra-Articular Fractures; Male; Stifle
PubMed: 31234746
DOI: 10.1177/1098612X19856180 -
European Journal of Trauma and... Dec 2018External fixation is associated with the risk of pin loosening and pin infection potentially associated to thermal bone necrosis during pin insertion.
INTRODUCTION
External fixation is associated with the risk of pin loosening and pin infection potentially associated to thermal bone necrosis during pin insertion.
OBJECTIVE
This study aims to investigate if the use of external fixator systems with unicortical pins reduces the heat production during pin insertion compared to fixators with bicortical pins.
METHODS
Porcine bone specimens were employed to determine bone temperatures during insertion of fixator pins. Two thermographic cameras were used for a simultaneous temperature measurement on the bone surface (top view) and a bone cross-section (front view). Self-drilling unicortical and bicortical pins were inserted at different rotational speeds: (30-600) rpm. Maximum and mean temperatures of the emerging bone debris, bone surface and bone cross-section were analyzed.
RESULTS
Maximum temperatures of up to 77 ± 26 °C were measured during pin insertion in the emerging debris and up to 42 ± 2 °C on the bone surface. Temperatures of the emerging debris increased with increasing rotational speeds. Bicortical pin insertion generated significantly higher temperatures at low insertion speed (30 rpm) CONCLUSION: The insertion of external fixator pins can generate a considerable amount of heat around the pins, primarily emerging from bone debris and at higher insertion speeds. Our findings suggest that unicortical, self-drilling fixator pins have a decreased risk for thermal damage, both to the surrounding tissue and to the bone itself.
Topics: Animals; Biomechanical Phenomena; Bone Nails; Disease Models, Animal; Fracture Fixation; Fractures, Bone; Swine; Temperature
PubMed: 29242952
DOI: 10.1007/s00068-017-0887-2 -
Canadian Journal of Veterinary Research... Jan 2022Acrylic columns are commonly used in external skeletal fixators, especially for fracture management or trans-articular fixations. To the authors' knowledge, there are no...
Acrylic columns are commonly used in external skeletal fixators, especially for fracture management or trans-articular fixations. To the authors' knowledge, there are no studies demonstrating if the number or position of the transfixation pins influence the ultimate strength and stiffness of the acrylic column. The objective of this study was to evaluate the effects of the number and position of transfixation pins (concentric eccentric) on the strength and stiffness of acrylic columns placed in axial compression. We hypothesized that strength and stiffness of acrylic columns under axial compression would not be affected by the number or position of the transfixation pins through the column. Three different groups of 12 acrylic columns were constructed with 4, 6, and 8 pins. In each group, 6 columns were constructed with the pins placed concentrically and the remaining 6 columns with the pins placed eccentrically. Each column was then placed under axial compression using a biomechanical testing machine. No significant differences were observed in ultimate strength regarding the number or position of transfixation pins ( = 0.83 and = 0.27, respectively). However, stiffness was significantly decreased for columns with 4 eccentric pins compared with columns with 6 and 8 eccentric pins ( < 0.01) and with columns with 4 concentric pins ( < 0.001). Although the effects of transfixation pins on the rigidity of acrylic columns do not appear to be clinically significant, these tests were performed only in compression and results might differ if complete external fixator systems are used with different models of testing. Future studies are recommended.
Topics: Animals; Biomechanical Phenomena; Bone Nails; External Fixators; Fracture Fixation; Fractures, Bone
PubMed: 34975220
DOI: No ID Found -
Annals of the Royal College of Surgeons... Jul 1978The transmaxillary K-wire is a simple, fast, safe, and effective technique for the fixation of unstable tractured malar bones. Combined with other techniques such as...
The transmaxillary K-wire is a simple, fast, safe, and effective technique for the fixation of unstable tractured malar bones. Combined with other techniques such as interdental fixation it simplifies and provides the fixation of the Le Fort II fracture or osteotomy and certain osteotomies used for facial advancement. The technique of insertion is described and illustrated.
Topics: Bone Nails; Fracture Fixation, Internal; Humans; Maxilla; Zygomatic Fractures
PubMed: 666241
DOI: No ID Found -
Veterinary and Comparative Orthopaedics... May 2019The aim of this study was to evaluate cyclic fatigue behaviour of a new pin with a thread run-out design in comparison with three other types of pins commonly used... (Comparative Study)
Comparative Study
OBJECTIVE
The aim of this study was to evaluate cyclic fatigue behaviour of a new pin with a thread run-out design in comparison with three other types of pins commonly used for equine transfixation pin casting.
MATERIALS AND METHODS
Twenty-four pairs of equine cadaveric third metacarpal bones (MC3) equipped with one transfixation pin placed horizontally in the distal metaphysis were tested using a simplified model, mimicking the biomechanical situation of equine transfixation pin casting. A 6.3/8.0-mm Imex Duraface pin with thread run-out design (ITROP) was compared with a 6.1-mm smooth Steinmann pin (SSP), a Securos 6.2-mm, positive-profile pin (SPPP) and an Imex 6.3-mm, positive-profile pin (IPPP) under cyclic loading until failure in axial compression of MC3.
RESULTS
All pins broke at clinically relevant load levels and cycle numbers. The SSP endured significantly ( = 0.0025) more cycles before failure (mean: 48685) than the ITROP (mean 25889). No significant differences in cycles to failure were observed comparing the SPPP versus ITROP, and the IPPP versus ITROP, respectively.
CLINICAL SIGNIFICANCE
A thread run-out design does not necessarily lead to higher resistance against pin breakage under cyclic loading conditions. The SSP was most resistant against cyclic failure in these testing conditions, even though it was associated with more lateromedial displacement and cortical wear-out. This could outweigh reported disadvantages of the SSP such as reduced resistance to axial extraction and pin loosening.
Topics: Animals; Biomechanical Phenomena; Bone Nails; Cadaver; Horses; Materials Testing; Prosthesis Failure
PubMed: 30847874
DOI: 10.1055/s-0039-1678734