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Instructional Course Lectures 2021The practicing orthopaedic surgeon must understand the relationship between fracture biomechanics and fracture biology to optimize patient outcomes. Patient... (Review)
Review
The practicing orthopaedic surgeon must understand the relationship between fracture biomechanics and fracture biology to optimize patient outcomes. Patient characteristics, fracture pattern, and desired type of bone healing all drive decision making. The benefits of performing an open approach to a fracture, obtaining an anatomic reduction, and achieving absolute stability must be weighed against the biologic cost to the tissues and the potential to compromise healing. Similarly, the decision to perform a closed fracture reduction; apply a splint, bridge plate, or intramedullary nail; and achieve relative stability requires that the surgeon understand the implications of increased strain at a given fracture site. The purpose of this chapter is to review the basic science of primary and secondary bone healing with special attention given to the clinical implications for practicing surgeons.
Topics: Biophysics; Bone Nails; Fracture Fixation, Intramedullary; Fracture Healing; Humans; Orthopedics
PubMed: 33438936
DOI: No ID Found -
The Journal of Hand Surgery... Sep 2020Distal Humerus Articular Fracture (classified by Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association as 13-B3) is an uncommon fracture with...
Distal Humerus Articular Fracture (classified by Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association as 13-B3) is an uncommon fracture with significant complications. We report results of 14 patients treated by open reduction and pin-and-plate fixation technique. In this retrospective study, we applied pin-and-plate fixation to 14 distal humerus articular fractures, in which screw fixation alone was inefficient or inadequate to provide stable fixation. After anatomical reduction of articular fragments, multiple Kirschner wires were inserted through the fragments. To prevent migration of Kirschner wires a small plate was placed proximally on the bent end of the pins. The average age of 14 patients (8 males and 6 females) was 36.4 years (range: 16-57) and the mean follow up period was 43 months (range: 12-80). At last follow up the average quick Disabilities of the Arm, Shoulder and Hand score was 18.9 (range: 2.3-42.5) and the mean points for Mayo Elbow Performance Index was 75.3 (range: 50-100). Mean final arc of flexion-extension was 97° (range: 40-131). Distal humerus articular fracture is sometimes difficult to fix with conventional methods. We used pin-and-plate technique that could make a stable fixation and allow early range of motion with acceptable results.
Topics: Adolescent; Adult; Bone Nails; Bone Plates; Disability Evaluation; Female; Fracture Fixation, Internal; Humans; Humeral Fractures; Male; Middle Aged; Range of Motion, Articular; Retrospective Studies; Young Adult
PubMed: 32723041
DOI: 10.1142/S242483552050037X -
International Orthopaedics Sep 2017External fixators are a well-established modality for treating fractures with bone defects, leg-length discrepancy, malunion, nonunion and other post-traumatic... (Review)
Review
External fixators are a well-established modality for treating fractures with bone defects, leg-length discrepancy, malunion, nonunion and other post-traumatic consequences. However, use of internal lengthening rods has remarkably increased recently for post-traumatic conditions. The main advantage of internal lengthening rods is eliminating pin-site complications. Internal lengthening rods are also associated with less pain. Motorised internal lengthening rods show promising performance in post-traumatic cases. Rigorous pre-operative planning is paramount to reducing lengthening-related complications. Certain types of internal lengthening rods offer bidirectional movement capability. Nail mechanism malfunction is a possibility with all kinds of nails. Direct doctor supervision is required, especially in the initial stages while the nail is lengthening. Internal lengthening nails are not as stiff as regular nails, with intricate internal mechanisms that can be broken under inattentive weightbearing activities. Preliminary positive outcomes indicate the role of internal lengthening rods in treating post-traumatic problems of leg-length discrepancy, malunion and nonunion.
Topics: Adolescent; Adult; Bone Nails; Female; Fractures, Bone; Humans; Leg Length Inequality; Male; Osteogenesis, Distraction; Treatment Outcome
PubMed: 28389837
DOI: 10.1007/s00264-017-3466-6 -
Veterinary Surgery : VS Jul 2023To compare pin placement accuracy, intraoperative technique deviations, and duration of pin placement for pins placed by free-hand probing (FHP) or 3D-printed drill...
OBJECTIVE
To compare pin placement accuracy, intraoperative technique deviations, and duration of pin placement for pins placed by free-hand probing (FHP) or 3D-printed drill guide (3DPG) technique.
SAMPLE POPULATION
Four greyhound cadavers.
METHODS
Computed tomography (CT) examinations from T6-sacrum were obtained for determination of optimal pin placement and 3DPG creation. Two 3.2/2.4-mm positive profile pins were inserted per vertebra, one left and one right from T7-L7 (FHP [n = 56]; 3DPG [n = 56]) by one surgeon and removed for repeat CT. Duration of pin placement and intraoperative deviations (unanticipated deviations from planned technique) were recorded. Pin tracts were graded by two blinded observers using modified Zdichavsky classification. Descriptive statistics were used.
RESULTS
A total of 54/56 pins placed with 3DPGs were assigned grade I (optimal placement) compared with 49/56 pins using the FHP technique. A total of 2/56 pins placed with 3DPGs and 3/56 pins using the FHP technique were assigned grade IIa (partial medial violation). A total of 4/56 pins placed using the FHP technique were assigned grade IIIa (partial lateral violation). No pins were assigned grade IIb (full medial violation). Intraoperative technique deviations occurred with 6/56 pins placed using the FHP technique and no pins with 3DPGs. Overall, pins were placed faster (mean ± SD 2.6 [1.3] vs. 4.5 [1.8] min) with 3DPGs.
CONCLUSIONS
Both techniques were accurate for placement of spinal fixation pins. The 3DPG technique may decrease intraoperative deviations and duration of pin placement.
CLINICAL RELEVANCE
Both techniques allow accurate pin placement in the canine thoracolumbar spine. The FHP technique requires specific training and has learning curve, whereas 3DPG technique requires specific software and 3D printers.
Topics: Dogs; Animals; Bone Nails; Fracture Fixation; Tomography, X-Ray Computed; Printing, Three-Dimensional
PubMed: 37071824
DOI: 10.1111/vsu.13958 -
The Journal of Foot and Ankle Surgery :... 2024Charcot reconstruction with static external fixation provides stability in deformity correction. Concern for pin site health remains forefront to prevent premature...
Charcot reconstruction with static external fixation provides stability in deformity correction. Concern for pin site health remains forefront to prevent premature fixator removal should infection develop. While previous investigations examined a spectrum of pin care protocol with a similar variation in outcomes, this study assesses results following a "no care pin care" routine. A retrospective analysis of patients with Charcot neuroarthropathy treated with static external fixation was performed where all pin sites were dressed using a chlorhexidine-soaked sponge without postoperative maintenance. Demographics, reconstruction-specific, and postoperative variables including pin site irritation, pin site infection, and pin tract infection were collected through frame removal. A comparison between uncomplicated and complicated pin sites was made. Statistical significance was set as p ≤ .05. Among 85 patients and their respective pin holes that posed potential spots of infection, 6 (7%) experienced pin site irritation and 5 (6%) experienced pin site infection. Moreover, 2 (2%) experienced a pin tract infection requiring removal. Out of the 768 wires/half-pins 2 (0.3%) were removed. There existed no statistically significant predictors of pin site irritation/infection other than age (p = .03). "No care pin care" proves an effective means at pin site care following static external fixation in Charcot reconstruction. Limited maintenance reduces the postoperative burden on providers and patients.
Topics: Humans; External Fixators; Retrospective Studies; Fracture Fixation; Bone Nails; Bone Wires
PubMed: 38043598
DOI: 10.1053/j.jfas.2023.11.008 -
Zeitschrift Fur Orthopadie Und... Apr 2024Proximal femoral fractures are frequent and complex injuries requiring prompt and targeted care. Numerous treatment strategies have been described, some of which have... (Review)
Review
Proximal femoral fractures are frequent and complex injuries requiring prompt and targeted care. Numerous treatment strategies have been described, some of which have been assessed and clinically implemented clinically. The aim of surgical is always the restoration of a pain-free and stable extremity. Mostly elderly patients are affected and treatment is associated with high postoperative complications and mortality rates. With increasing numbers of patients, the topic is of great medical and economic relevance. In this work, the choice of implants for the osteosynthesis of proximal femoral fractures - as depending on the fracture type - will be examined, as based on a review of current literature. Standard care includes cannulated screws, sliding hips screws and cephalomedullary nails. In addition, the influence of implant positioning, fracture reduction and additional measures such as cement augmentation are evaluated and discussed. Careful fracture reduction and the quality of implant positioning are paramount in order to avoid complications.
Topics: Humans; Aged; Hip Fractures; Proximal Femoral Fractures; Fracture Fixation, Internal; Postoperative Complications; Extremities; Bone Nails; Fracture Fixation, Intramedullary; Femur
PubMed: 36167326
DOI: 10.1055/a-1904-8551 -
Veterinary and Comparative Orthopaedics... Mar 2020The objectives of this study were to validate a finite element model of the equine distal limb transfixation cast and to determine the effect of six transcortical pin...
OBJECTIVE
The objectives of this study were to validate a finite element model of the equine distal limb transfixation cast and to determine the effect of six transcortical pin parameters on bone-pin interface (BPI) stresses in the third metacarpal bone.
STUDY DESIGN
A transfixation cast finite element model was developed from a computed tomography scan of the third metacarpal bone and modelled pin elements. The model was validated by comparing strain measured around a 6.3-mm transfixation pin in the third metacarpal bone with the finite element model. The pin parameters of diameter, number, location, spacing, orientation and material were evaluated by comparing a variety of pin configurations within the model.
RESULTS
Pin diameter and number had the greatest impact on BPI stress. Increasing the diameter and number of pins resulted in lower BPI stresses. Diaphyseal pin location and stainless-steel pins had lower BPI stresses than metaphyseal location and titanium alloy pins, respectively. Offset pin orientation and pin spacing had minimal impact on BPI stresses during axial loading.
CONCLUSION
The results provide evidence that diameter and number are the main pin parameters affecting BPI stress in an equine distal limb transfixation cast. Configurations of various pin size and number may be proposed to reduce BPI stresses and minimize the risk of pin related complications. Further refinement of these models will be required to optimize pin configurations to account for pin hole size and its impact on overall bone strength.
Topics: Animals; Biomechanical Phenomena; Bone Nails; Cadaver; External Fixators; Finite Element Analysis; Horses; Metacarpal Bones; Stress, Mechanical
PubMed: 31858512
DOI: 10.1055/s-0039-3399576 -
Scientific Reports Feb 2024In estimated 10-15% of neurosurgical interventions employing a conventional three-pin head fixation device (HFD) the patient's head loses position due to slippage. At...
In estimated 10-15% of neurosurgical interventions employing a conventional three-pin head fixation device (HFD) the patient's head loses position due to slippage. At present no scientifically based stability criterion exists to potentially prevent the intraoperative loss of head position or skull fractures. Here, data on the skull penetration depth both on the single and two-pin side of a three-pin HFD are presented, providing scientific evidence for a stability criterion for the invasive three-pin head fixation. Eight fresh, chemically untreated human cadaveric heads were sequentially pinned 90 times in total in a noncommercially calibrated clamp screw applying a predefined force of 270 N (approximately 60 lbf) throughout. Three head positions were pinned each in standardized manner for the following approaches: prone, middle fossa, pterional. Titanium-aluminum alloy pins were used, varying the pin-cone angle on the single-pin side from 36° to 55° and on the two-pin side from 25° to 36°. The bone-penetration depths were directly measured by a dial gauge on neurocranium. The penetration depths on the single-pin side ranged from 0.00 mm (i.e., no penetration) to 6.17 mm. The penetration depths on the two-pin side ranged from 0.00 mm (no penetration) to 4.48 mm. We measured a significantly higher penetration depth for the anterior pin in comparison to the posterior pin on the two-pin side in prone position. One pin configuration (50°/25°) resulted in a quasi-homogenous pin depth distribution between the single- and the two-pin side. Emanating from the physical principle that pin depths behave proportionate to pin pressure distribution, a quasi-homogenous pin penetration depth may result in higher resilience against external shear forces or torque, thus reducing potential complications such as slippage and depressed skull fractures. The authors propose that the pin configuration of 50°/25° may be superior to the currently used uniform pin-cone angle distribution in common clinical practice (36°/36°). However, future research may identify additional influencing factors to improve head fixation stability.
Topics: Humans; Skull; Bone Nails; Bone Screws; Skull Fractures; Head
PubMed: 38413760
DOI: 10.1038/s41598-024-55227-x -
European Journal of Orthopaedic Surgery... Oct 2023Tibio-talo-calcaneal arthrodesis (TTCA) is considered a safe and valuable option for end-stage tibiotalar and subtalar arthritis, and usually is performed with a... (Review)
Review
PURPOSE
Tibio-talo-calcaneal arthrodesis (TTCA) is considered a safe and valuable option for end-stage tibiotalar and subtalar arthritis, and usually is performed with a retrograde intramedullary nail. Although the good results reported, potential complications may be related to retrograde nail entry point. Aim of this systematic review is to analyze in cadaveric studies the risk of iatrogenic injuries related to different entry points and different retrograde intramedullary nail design when performing TTCA.
METHODS
According to PRISMA, a systematic review of the literature was performed on PubMed, EMBASE and SCOPUS databases. A subgroup analysis comparing different entry point location (anatomical or fluoroscopic guided) and different nail design (straight vs. valgus curved nails) was performed.
RESULTS
Five studies were included, for a total of 40 specimens. Superiority of anatomical landmark-guided entry points was observed. Different nail designs did not seem to influence nor iatrogenic injuries neither hindfoot alignment.
CONCLUSION
Retrograde intramedullary nail entry point should be placed in the lateral half of the hindfoot in order to minimize the risk of iatrogenic injuries.
Topics: Humans; Treatment Outcome; Retrospective Studies; Bone Nails; Arthrodesis; Iatrogenic Disease; Ankle Joint
PubMed: 36906879
DOI: 10.1007/s00590-023-03512-2 -
The Journal of Arthroplasty Sep 2017There has been a great increase in the use of navigation technology in joint arthroplasty. In most types of navigation-assisted surgery, several temporary navigation...
BACKGROUND
There has been a great increase in the use of navigation technology in joint arthroplasty. In most types of navigation-assisted surgery, several temporary navigation pins are placed in the patient. Goals of this study are (1) to identify complications and (2) risk factors associated with placement of these pins.
METHODS
This is a retrospective cohort study of all navigation-assisted hip and knee arthroplasty performed a single institution over a 3-year period. Records were reviewed and outcome measures were tabulated in a database. Complications included in the database were pin site infection, deep prosthetic joint infection, neurologic injury, vascular injury, and fracture through a pin site.
RESULTS
A total of 3136 pin sites in 839 patients were included in the study. Five pin site complications were reported with a complication rate of 0.16% per pin site and 0.60% per patient. The complications-per-procedure were slightly higher for unicondylar knee arthroplasty (0.64%) compared with patellofemoral arthroplasty (0%) and total hip arthroplasty (0.46%), but not statistically significant. There were three infections, one neuropraxia, and one suture abscess. No periprosthetic fractures through a pin site were reported. All complications were resolved with nonoperative treatment. The infections required oral antibiotics, and were associated with transcortical drilling in two cases and juxtacortical drilling in the third.
CONCLUSION
Pins required for navigation-assisted arthroplasty have a low complication rate. Transcortical or juxtacortical drilling may be a risk factor for pin site infection; future studies should be directed at quantifying this effect.
Topics: Adult; Aged; Arthroplasty, Replacement, Hip; Arthroplasty, Replacement, Knee; Bone Nails; Female; Humans; Male; Middle Aged; Prosthesis-Related Infections; Retrospective Studies; Risk Factors; Surgery, Computer-Assisted
PubMed: 28522245
DOI: 10.1016/j.arth.2017.03.073