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Surgical Technology International May 2020Magnetically controlled intramedullary lengthening nails (MCILN) have revolutionized the field of limb lengthening and deformity correction. They allow for accurate and... (Review)
Review
Magnetically controlled intramedullary lengthening nails (MCILN) have revolutionized the field of limb lengthening and deformity correction. They allow for accurate and precise distraction with excellent patient outcomes and satisfaction. Though potentially technically easier than external fixation, general deformity principles and bone and soft-tissue biology must be considered for successful use. MCILN can address deformities of a wide range of etiologies including congenital, posttraumatic, post-infectious, tumor, and many others with excellent healing rates and outcomes as well as better patient satisfaction and similar cost compared to external fixation. Of the approximately 10,000 MCILN that have been implanted (written communication, NuVasive, Inc., San Diego, California), about 749 cases have been reported in the published literature. Applications outside of deformity correction are on the rise, with new uses reported in reconstruction after tumor resection and acute trauma. This review of MCILN summarizes the history, recent advances, and results of MCILN treatment in a multitude of clinical applications.
Topics: Bone Nails; Femur; Humans; Leg Length Inequality; Nails; Treatment Outcome
PubMed: 32297969
DOI: No ID Found -
International Journal of Surgery... Oct 2015Intramedullary nails (IM nails) now include dedicated fibular nails for lateral malleolus fractures. This study reviewed nail versus plate for fixation of unstable ankle... (Comparative Study)
Comparative Study Review
INTRODUCTION
Intramedullary nails (IM nails) now include dedicated fibular nails for lateral malleolus fractures. This study reviewed nail versus plate for fixation of unstable ankle fractures.
DESIGN
Systematic review and meta-analysis of published reports.
RESULTS
Four studies met the inclusion criteria, including 375 patients. Two included studies were randomised-control studies and two were non-randomised case series. The implants investigated included: Knowles Pins, Fibular Nails, Rush Rods and Inyo Nails. The overall risk of bias was high. Pooled data showed a statistically significant lower risk of wound infection (RR 0.10; 95% CI 0.02 to 0.44), symptomatic hardware (RR 0.14; 95% CI 0.05 to 0.35) and removal of hardware (RR 0.57; 95% CI 0.39 to 0.81) with intramedullary nail fixation.
CONCLUSIONS
There is a paucity of literature upon which to draw reliable conclusions. There was a high risk of bias towards favourable outcomes for the nail group. It would appear that intramedullary nail fixation of distal fibular fractures can outperform conventional fixation with plate and screws. There is a need for adequately powered, scientific trials.
Topics: Ankle Fractures; Bone Nails; Bone Plates; Fracture Fixation, Internal; Humans
PubMed: 26255000
DOI: 10.1016/j.ijsu.2015.07.697 -
Journal of Orthopaedic Surgery (Hong... 2022The concept of antibiotic-coated implants, mainly coated intramedullary nails, has become increasingly used for the treatment of fracture related infections. After a... (Review)
Review
The concept of antibiotic-coated implants, mainly coated intramedullary nails, has become increasingly used for the treatment of fracture related infections. After a long period of hand-made implants, commercially fabricated implants combine several benefits. Antibiotic-coated nails constitute a solid treatment option for unstable diaphyseal infections with fractures or non-unions. They release high concentrations of antibiotics locally, while retaining reduction and providing axial stability. This review aims to provide an overview about the background, the development, the indications, the treatment strategies and the outcomes of antibiotic-coated intramedullary nails.
Topics: Humans; Anti-Bacterial Agents; Bone Nails; Fractures, Bone; Fracture Fixation, Intramedullary; Treatment Outcome
PubMed: 36545939
DOI: 10.1177/10225536221118521 -
Journal of Surgical Orthopaedic Advances 2023Distal femoral skeletal traction is a common procedure for the stabilization of fractures of the pelvis, acetabulum, and femur following trauma. Femoral traction pins...
Distal femoral skeletal traction is a common procedure for the stabilization of fractures of the pelvis, acetabulum, and femur following trauma. Femoral traction pins are traditionally inserted via medial-to-lateral (MTL) entry to accurately direct the pin away from the medial neurovascular bundle. Alternatively, cadaveric studies have demonstrated low risk to the neurovascular bundle using a lateral-to-medial (LTM) approach. The purpose of this study was to compare the incidence of complications of LTM and MTL femoral traction pin placement at a single institution. This was a retrospective review of patients from the orthopaedic consult registry at a academic Level I Trauma Center. We identified 233 LTM femoral traction pin procedures in 231 patients and 29 MTL pin procedures in 29 patients. The two pin placement techniques were compared with respect to complications, specifically the incidence of neurovascular injury, cellulitis, septic arthritis, osteomyelitis, and heterotopic ossification after femoral traction pin placement. Two complications were reported. One patient developed heterotopic ossification along the pin tract after LTM traction pin placement. Another patient developed septic arthritis after LTM pin placement, likely attributable to retrograde intramedullary nailing of his open femur fracture rather than his traction pin. There were no reports of neurovascular injury, cellulitis, or osteomyelitis associated with pin placement. The complication rate was 0.9% for LTM group and 0.0% for MTL group (p = 0.616). LTM femoral traction pin placement is a safe procedure with a similarly low complication rate compared with traditional MTL placement when the limb is positioned in neutral alignment. (Journal of Surgical Orthopaedic Advances 32(4):259-262, 2023).
Topics: Humans; Traction; Cellulitis; Femur; Femoral Fractures; Bone Nails; Fracture Fixation, Intramedullary; Lower Extremity; Arthritis, Infectious; Osteomyelitis; Ossification, Heterotopic
PubMed: 38551235
DOI: No ID Found -
Veterinary Surgery : VS Jul 2023To determine whether one larger or two smaller diameter pins used for tibial tuberosity avulsion fracture (TTAF) stabilization provides greater axial tensile strength...
OBJECTIVE
To determine whether one larger or two smaller diameter pins used for tibial tuberosity avulsion fracture (TTAF) stabilization provides greater axial tensile strength and stiffness when subjected to monotonic mechanical load to failure in normal skeletally mature canine cadavers.
STUDY DESIGN
Paired ex vivo biomechanical study.
SAMPLE POPULATION
Eleven pairs of adult cadaveric dog tibias.
METHODS
Twenty-two tibias from 11 dogs were collected to model a TTAF. Each limb of a pair was randomly assigned a one or two-pin fixation. Tibias were subjected to monotonic, axial load to failure. Fixation stiffness, strength, and pin insertion angles were analyzed with parametric testing. Significance was set at p < .05.
RESULTS
The mean strength of the single-pin fixation was 426.2 ± 50.5 N compared to two-pin fixation at 639.2 ± 173.5 N (p = .003). The mean stiffness of the single-pin fixation was 57.3 ± 18.7 N/mm and the two-pin fixation was 71.7 ± 20.5 N/mm (p = .029). The normalized ratio between one and two-pin fixation had a mean stiffness of 68% ± 25.8% and strength of 82.8% ± 24.6%.
CONCLUSIONS
In an ex vivo cadaveric TTAF model, vertically aligned two-pin fixation offers greater strength and stiffness when compared to a single-pin fixation.
CLINICAL SIGNIFICANCE
When repairing TTAF, surgeons should aim to apply two vertically aligned pins rather than a single pin for greater strength and stiffness.
Topics: Dogs; Animals; Fractures, Avulsion; Bone Nails; Tibial Fractures; Tibia; Cadaver; Biomechanical Phenomena; Fracture Fixation; Dog Diseases
PubMed: 37073566
DOI: 10.1111/vsu.13961 -
Medicine Jun 2021Closed reduction with percutaneous pin fixation is commonly used to treat pediatric supracondylar humerus fractures. Various pin configurations of varying biomechanical... (Comparative Study)
Comparative Study
Closed reduction with percutaneous pin fixation is commonly used to treat pediatric supracondylar humerus fractures. Various pin configurations of varying biomechanical strength have been described. However, to our knowledge, no biomechanical study has focused on pin alignment in the sagittal plane. Our goal was to compare the stability of fixation using 3 different pin constructs: 3 lateral pins diverging in the coronal plane but parallel in the sagittal plane (3LDP), 3 lateral pins diverging in the coronal and sagittal planes (3LDD), and 2 crossed pins (1 medial and 1 lateral).Transverse fractures were made through the olecranon fossa of 48 synthetic humeri, which were then reduced and pinned in the 3LDP, 3LDD, and crossed-pin configurations (16 specimens per group) using 1.6-mm Kirschner wires. The sagittal plane pin spread was significantly greater in the 3LDD group than in the 3LDP group, whereas we found no difference in the coronal plane. Sagittal extension testing was performed from 0° to 20° at 1°/s for 10 cycles using a mechanical torque stand. The torque required to extend the distal fragment 20° from neutral was compared between groups using one-way analysis of variance with multiple comparison post-hoc analysis. P values ≤.05 were considered significant.The 3LDD configuration was more stable than the 3LDP and crossed-pin configurations. The mean torque required to displace the pinned fractures was 5.7 Nm in the 3LDD group versus 4.1 Nm in the 3LDP group and 3.7 Nm in the crossed-pin group (both, P < .01). We found no difference in stability between the 3LDP and crossed-pin groups (P = .45).In a synthetic biomechanical model of supracondylar humerus fracture, sagittal alignment influenced pin construct stability, and greater pin spread in the sagittal plane increased construct stability when using 3 lateral pins. The lateral pin configurations were superior in stability to the crossed-pin configuration.Level of Evidence: Level V.
Topics: Adult; Biomechanical Phenomena; Bone Nails; Bone Wires; Child; Closed Fracture Reduction; Fracture Fixation, Internal; Humans; Humeral Fractures; Iatrogenic Disease; Models, Anatomic; Torque; Ulnar Nerve
PubMed: 34087880
DOI: 10.1097/MD.0000000000026173 -
Journal of Pediatric Orthopedics Mar 2019We assessed the effect on the torsional stability by different pin diameters and varied pin configurations in a biomechanical supracondylar humerus fracture model.
BACKGROUND
We assessed the effect on the torsional stability by different pin diameters and varied pin configurations in a biomechanical supracondylar humerus fracture model.
METHODS
After scanning a model of a pediatric humerus, the image was imported into software. Variable pin trajectories were planned. Acrylonitrile butadiene styrene plastic models were 3-dimensionally printed with predetermined pin trajectories. Models were osteotomized and potted with a polyurethane resin. Five-pin configurations were designed to test coronal and sagittal patterns of pin placement. Each included 3 lateral pins and a medial pin. Pin diameters of 1.6, 2.0, and 2.4 mm were tested in all configurations. Three models for each pin diameter/configuration were tested to ensure uniformity. Stability of the construct was tested to determine the torque needed to deflect the osteotomy 10 degrees in internal/external rotation. Each model was tested 3 times.
RESULTS
In all models/configurations, the 2.4 mm pin diameter was statistically stiffer than 1.6 mm diameter pins; this lost statistical significance in certain patterns when comparing 2.0- and 2.4-mm pins. When comparing a divergent to a parallel configuration in the coronal plane, there was no significant difference in stability when pin diameter or number were controlled. The convergent pin configuration was, in general, the least stable pattern. Use of a medial pin conferred statistically significant stiffness throughout most models as demonstrated with pin deletion. Use of 2 pins was significantly less stiff than most 3-pin models.
CONCLUSIONS
Larger pin diameters confer greater stiffness among all patterns. The use of 3 lateral and 1 medial pin was not statistically different than 2 lateral and 1 medial pin in our models. Both patterns were stiffer than 3 lateral pins only or other fewer pin constructs. The alignment of pins in the sagittal plane did not affect overall construct stiffness.
Topics: Biomechanical Phenomena; Bone Nails; Child; Fracture Fixation, Internal; Humans; Humeral Fractures; Humerus; Models, Anatomic; Printing, Three-Dimensional; Prosthesis Design; Torque
PubMed: 30300279
DOI: 10.1097/BPO.0000000000001270 -
Journal of Shoulder and Elbow Surgery Jul 2022Closed reduction and percutaneous pinning is still a preference for the treatment of supracondylar humerus fractures in children. However, no reports have shown the pin...
BACKGROUND
Closed reduction and percutaneous pinning is still a preference for the treatment of supracondylar humerus fractures in children. However, no reports have shown the pin trajectory and the characteristics of the entry point so far. So we established a computational simulation model of the elbow to observe the trajectory of pinning for supracondylar humerus fractures.
METHODS
We reconstructed an adult elbow computationally and simulated pin placement through lateral and medial pinning. Pin trajectories were traced after placement and after the addition of the skin profile; the relative entry points of the pins were determined. We used the center of the dorsal olecranon inflection as an anatomic reference for the entry points of lateral pinning. Four quadrants were established based on the center of the dorsal olecranon inflection: upper medial quadrant, upper lateral quadrant, lower medial quadrant, and lower lateral quadrant (LLQ).
RESULTS
The maximum angle of pinning through the lateral column was 64° ± 3°. The minimum angles of pinning through the lateral column and middle column were 37° ± 3° and 20° ± 2°, respectively. The range of safe angle pinning through the medial column was between 18° ± 2° and 57° ± 3° to avoid penetration of the olecranon fossa and the cortex of the medial column. The entry points of lateral pinning were within the lateral half of the LLQ, and the lateral one-third of the LLQ contained all entry points of the pins through the lateral column and minor points of the pins through the middle column. The exit points of the medial pinning were within the lateral fringe of the metaphyseal-diaphyseal junction region; entering from the inferior two-thirds of the medial epicondyle could lead to the exit points in the proximal half of the metaphyseal-diaphyseal junction region laterally.
DISCUSSION
For lateral pinning, the entry points would be within the lateral half of the LLQ. For the pins through the lateral column, the entry points should be within the lateral one-third of the LLQ. For medial pinning, entering from the inferior two-thirds of the medial epicondyle would lead to a more proximal exit.
Topics: Bone Nails; Bone Wires; Child; Diaphyses; Fracture Fixation; Humans; Humeral Fractures; Humerus
PubMed: 35151881
DOI: 10.1016/j.jse.2021.12.048 -
Proceedings of the Institution of... Mar 2019This article aims to review the biomechanical evolution of intramedullary nailing and describe the breakthrough concepts which allowed for nail improvement and its...
This article aims to review the biomechanical evolution of intramedullary nailing and describe the breakthrough concepts which allowed for nail improvement and its current success. The understanding of this field establishes an adequate background for forthcoming research and allows to infer on the path for future developments on intramedullary nailing. It was not until the 1940s, with the revolutionary Küntscher intramedullary nailing design, that this method was recognized as a widespread medical procedure. Such achievement was established based on the foundations created from intuition-based experiments and the first biomechanical ideologies. The nail evolved from allowing alignment and stability through press-fit fixation with nail-cortical wall friction to the nowadays nail stability achieved through interlocking screws mechanical linkage between nail and bone. Important landmarks during nail evolution comprise the introduction of flexible reaming, the progress from slotted to non-slotted nails design, the introduction of nail 'dynamization' and the use of titanium alloys as a new nail material. Current biomechanical improvement efforts aim to enhance the bone-intramedullary nail system stability. We suggested that benefit would be attained from a better understanding of the ideal mechano-biological environment at the fracture site, and future improvements will emerge from combining mechanics and biological tools.
Topics: Alloys; Biomechanical Phenomena; Bone Nails; Fracture Fixation, Intramedullary; Mechanical Phenomena; Titanium
PubMed: 30887900
DOI: 10.1177/0954411919827044 -
Journal of Pediatric Orthopedics Aug 2020Over the past 5 years, published literature regarding treatment of pediatric limb deformity and limb length discrepancy demonstrates much interest in better... (Review)
Review
Over the past 5 years, published literature regarding treatment of pediatric limb deformity and limb length discrepancy demonstrates much interest in better understanding, categorizing and treating these challenging problems. Many studies explore expanding and refining indications for traditional treatment methods like guided growth techniques. Other studies have evaluated the results of new techniques such as lengthening via mechanized intramedullary nails. Additionally, series comparing older and newer techniques such as lengthening with external devices versus mechanized nails are becoming increasingly available.
Topics: Bone Lengthening; Bone Nails; Child; Fracture Fixation, Intramedullary; Humans; Leg Length Inequality
PubMed: 31688516
DOI: 10.1097/BPO.0000000000001456