Solid Screw Research Articles

Comparison of Clinical and Radiographic Outcomes Between Solid Headless and Headed Screws in the Treatment of Zone II and III Fifth Metatarsal Fractures in Elite Athletes

Background: Zone II and III fifth metatarsal (5-MT) fractures among athletes are typically managed with percutaneous fixation following anatomic reduction. However, screw head discomfort and refracture after bone union can occur because of the loads placed on the foot during play. Several hardware systems that use a smaller screw head compared to traditional hardware systems have been developed to minimize the rate of postoperative hardware complications. This study compares clinical and radiographic outcomes of 5-MT fractures in elite athletes treated with a solid headless screw vs a solid headed screw. We hypothesized that the headless screw would be associated with faster union rates, faster clearance times, and lower incidence of symptomatic hardware compared to the headed screw. Methods: Athletes competing at a collegiate level or higher treated for a zone II or III 5-MT fracture between 2016 and 2022 by 2 surgeons fellowship-trained in foot and ankle orthopaedics were screened. Operative notes were reviewed to determine the hardware system used. Subjects were divided based on the hardware system used during operation: headed screw and headless screw. Time to radiographic union, time to full clearance, and return to competition were determined. Postoperative complications, including nonunions, need for revision, need for hardware removal, and refractures were also noted. Results: Forty eligible patients (44 feet) were identified. The solid headed screw group included 20 patients (21 fractures), and the solid headless screw group included 20 patients (23 fractures). Average time to union for the headed screw group was 11.78 (range, 5.86-19.00) weeks; average time to union for the headless screw group was 11.65 (range, 6.00-22.57) weeks ( P = .93). Nineteen out of twenty (95%) patients were able to return to competition in both groups. Average time to return to competition for the headed screw group was 26.9 (range, 10.00-47.86) weeks, while average time for the headless screw group was 21.2 (range, 6.86-55.00) weeks ( P = .55). The overall complication rate for the headed screw was 23.8%, which was not statistically different from the overall complication rate for the headless screw of 13.0% ( P = .35). Conclusion: In this relatively small sample of elite athletes undergoing operative fixation of a 5-MT fracture, fixation using either a headless or headed screw system had similar good outcomes in regard to times to union, return to competition, and complication rate regardless of solid screw head type used. Level of Evidence: Level III, retrospective cohort study.

The Use of Knotless Suture Tape Construct vs Screw Fixation for Lisfranc Injuries: A Cadaveric Biomechanical Study.

Lisfranc injuries are often treated with open reduction and internal fixation using rigid fixation techniques. The use of flexible fixation to stabilize the Lisfranc joint is a newer technique. The purpose of this cadaveric study is to compare the amount of diastasis at the Lisfranc interval under diminished physiologic loads when treated with a knotless suture tape construct and a solid screw. Ten cadavers (20 feet) had native motion at the intact Lisfranc interval assessed at multiple increasing loads (69, 138, and 207 N). The Lisfranc ligamentous complex was then disrupted, and testing repeated to evaluate the amount of diastasis. Randomization was performed to determine the type of fixation for each cadaver: solid screw or knotless suture tape construct. Once fixation was completed, specimens were cyclically loaded for 10 000 cycles at loads, and diastasis was quantified after each load cycle to compare the interventions. Diastasis was measured using motion tracking cameras and retroreflective marker sets. A non-inferiority statistical analysis was performed. Diastasis mean values were confirmed to be >2 mm for all load bearing conditions in the injury model. Posttreatment, diastasis was significantly reduced when compared to the sectioned conditions (P < .01) for both treatment options. Non-inferiority analyses showed that the knotless suture tape construct did not perform inferior to screw fixation for diastasis at the Lisfranc interval at any of the compared load states. Under the loads tested, there is no significant difference in diastasis at the Lisfranc interval when treating ligamentous Lisfranc injuries with a knotless suture tape construct or solid screws. Both reduced diastasis from the injured state and were not different from the intact state. In this cadaveric model with ligamentous Lisfranc injury, diastasis of a knotless suture tape construct is compared to solid screw fixation as tested.

Microwave device for heat treatment of meat by-products and waste

BACKGROUND: In the conditions of farms, there is a problem of neutralizing unpleasant odors during heat treatment of secondary meat raw materials to preserve the consumer properties of protein feed at low operating costs. AIM: Development of the device for heat treatment with disinfection and neutralization of the unpleasant odor of crushed secondary meat raw materials with the integral effect of an ultra−high frequency electromagnetic field, a bactericidal flow of UV rays and ozone in a continuous mode with electromagnetic safety ensured. METHODS: The raw materials are the stomach chambers of ruminants. The basic idea, principle of operation and design of the device are based on the propagation of microwave oscillations in a resonator with a spiral decelerating system. The microwave device contains a non-ferromagnetic cylinder with a perforated lower base, a coaxially arranged non-ferromagnetic spiral cylinder and an electrically driven fluoroplastic auger with a solid screw surface. The average perimeter of the annular volume, between the cylinder and the spiral cylinder forming the coaxial resonator, and its height are multiples of half-wavelength. Corona brushes are mounted to the annular base of the cylinder, under which electric gas discharge lamps powered by 1 kHz frequency generators are radially located, and a ceramic annular spherical surface is located under the lamps. Magnetrons are mounted along the perimeter of the outer cylinder with a shift of 120 degrees. The crackling is removed using a pneumatic conveyor. RESULTS: The feature of the coaxial resonator is that the inner core is formed as a spiral decelerating system. Therefore, the intrinsic Q-factor of the resonator is high, about 115000, therefore, the expected thermal efficiency is 0.7–0.75. The factor of dielectric losses of raw materials with a decrease in humidity from 76% to 30% is reduced by five times. Thus, while keeping the electric stress at the level of 1.2–2 kV/cm, the electromagnetic field power dissipated in a unit of the volume of the crackling decreases by five times, from 34 500 to 6800 W/cm3. CONCLUSIONS: A new design solution with a spiral coaxial resonator, the use of a ceramic reflector, and a number of physical factors made it possible to develop the design of the operation chamber for the heat treatment of ruminant slaughter waste with the neutralization of unpleasant odors with a capacity of 30–35 kg/h and specific energy costs of 0.16–0.19 kWh/kg.

The positional consistency between guidewire and cannulated or solid screw in robot-assisted spinal internal fixation surgery

BackgroundThis study aimed to investigate the positional consistency between the guidewire and the screw in spinal internal fixation surgery.MethodsThis study involved 64 patients who underwent robot-assisted thoracic or lumbar pedicle screw fixation surgery. Guidewires were inserted with the assistance of the Tirobot. Either cannulated screws or solid screws were inserted. Guidewire and screw accuracy was measured using CT images based on the Gertzbein and Robbins scale. The positional consistency between guidewire and screw was evaluated based on the fused CT images, which could graphically and quantitatively demonstrate the consistency. The consistency was evaluated based on a grading system that considered the maximum distance and angulation between the centerline of the guidewire and the screw in the region of the pedicle.ResultsA total of 322 screws were placed including 206 cannulated ones and 116 solid ones. Based on the Gertzbein and Robbins scale, 97.5% of the guidewires were grade A, and 94.1% of the screws were grade A. Based on our guidewire-screw consistency scale, 85% in cannulated group, and 69.8% in solid group, were grade A. Both solid and cannulated screws may alter trajectory compared to the guidewires. The positional accuracy and guidewire-screw consistency in the solid screw group is significantly worse than that in the cannulated screw group. The cortical bone of the pedicle has a positive guide effect on either solid or cannulated screws.ConclusionThe pedicle screws may alter trajectory despite the guidance of the guidewires. Solid screws show worse positional accuracy and guidewire-screw consistency compared with cannulated screws.Trial registration The study was retrospectively registered and approved by our center’s institutional review board.

Blood Loss Following Open Posterior Spinal Fusion in Fractures: Cannulated vs. Solid Pedicle Screws.

We aim to delineate whether there is increased blood loss with the use of cannulated pedicle screws compared to solid pedicle screws in patients undergoing posterior spinal fusion. A single-centre retrospective case-control study was undertaken on patients undergoing PSF for spinal fractures. Cannulated screw fixation was compared with solid screw fixation. Intraoperative blood loss was estimated using pre and postoperative haemoglobin levels, recorded estimated blood loss and cell saver reports. Anticoagulation, blood product administration, operative time and number of levels fused were assessed. A total of 64 cases, 32 in each cohort, were included in the analysis. Overall mean haemoglobin reduction from pre- to post-operative was 2.82 ± 1.85 g/L per screw inserted in the cannulated group, compared to a haemoglobin decrease of 2.81 ± 1.521 g/L per screw inserted in the solid screw group (p = 0.971). Total estimated intraoperative blood loss was 616.3 + 355.4 mL in the cannulated group, compared to 713.6 + 473.5 mL in the solid screw group (p = 0.456). Patients with preoperative thrombocytopenia had a transfusion rate of 0.5 ± 0.71 units/patient compared to 0.04 ± 0.19 units/patient in patients with normal platelet levels (p < 0.005). The differences in blood loss observed between cannulated and solid pedicle screws are non-significant overall. The largest predictor for need of transfusion was pre-operative thrombocytopenia, regardless of the type of screw used.

ANALYSIS OF THE OPERATION OF FEED SHREDDERS-MIXERS WITH SCREW WORKING BODIES AS CUTTING ELEMENTS

The possibility of reducing the energy consumption of grinding mechanisms is being considered. The work of existing designs of shredders-feed mixers is analyzed. Disadvantages of shredders with hammer, pin and knife working bodies are noted. The original design of the cutting elements, which consists of two screws, is proposed. One screw working body is made with a solid screw and installed inside the second screw working body with a belt screw. The directions of rotation of the augers are opposite. A screw with a solid screw is used as an anticutting element. The turns of the augers are located at an angle to the central axis in the horizontal plane. This provides the necessary sharpening angle, as a result of which the working part of the cutting elements has the shape of a onesided wedge. Kinematic and force analyses of the grinding mechanism are carried out in the article. The variants of using augers with the inclination of the turns in parallel and cross directions are considered. It is established that when the turns are tilted in parallel, chopping cutting is carried out in the grinding mechanism. In this case, the material is crushed in the gap along the entire length of the helix. When the coils are tilted crosswise, sliding cutting is carried out. The material is crushed at the points of intersection of the turns, and the mechanism works like a segment apparatus of harvesting machines. Plans of the forces acting on the cutting elements are constructed and the condition of pinching of the processed material in the cutting pair is determined. The expediency of the grinding mechanism with cheeks acting as cutting elements considered design using is substantiated.

First Tarsometatarsal Joint Fusion for Hallux Valgus Deformity: A Retrospective Comparison of Two Fixation Constructs Regarding Initial Maintenance of Correction and Complications: Traditional Crossing Screw Fixation Versus Dorsomedial Locking Plate and Intercuneiform Compression Screw

Various fixation constructs exist to address hallux valgus when performing a first tarsometatarsal joint arthrodesis. The goal of this present study is to compare complication rates, and degree and maintenance of angular correction between a dorsomedial locking plate with intercuneiform compression screw construct versus traditional crossing solid screw fixation construct. The plate plus intercuneiform compression screw construct fixation utilized a combined sagittal saw and curette method of joint preparation while the crossed screw fixation group utilized a curette and bur technique. A retrospective review was conducted of consecutive patients who underwent a midfoot fusion using either constructs. Sixty four total feet in 56 patients were enrolled in the study. Twenty four consecutive patients (32 feet) who underwent a midfoot arthrodesis using the locking plate and intercuneiform fixation were fully fused (100%) by 10 weeks postoperatively, with no incidents of nonunion and one deep vein thrombosis event. Thirty two consecutive patients (32 feet) who underwent midfoot arthrodesis with crossing screw fixation had 2 nonunion events, one that was asymptomatic and the other that required a revision midfoot fusion. There was a statistically significant improvement from the pre-operative intermetatarsal angle, hallux abductus angle compared to the 10 week and 1 year radiographs (p < .05) for the entire cohort for both fixation constructs. There was a statistically significant increase in American College of Foot and Ankle Surgery first ray scores from pre-op to 1 year follow-up for both fixation constructs. Overall, the dorsomedial locking plate plus intercuneiform compression screw fixation construct better maintains Intermetatarsal angle (IMA) correction at midterm follow-up compared to the traditional crossing screw construct. Both cohorts overall demonstrate similar fusion rates at 10 weeks, nonunion events, incidences of broken hardware, hardware removal, deep vein thrombosis, neuritis at 1 year postoperatively, and hallux varus.

Stress Fractures of the Fifth Metatarsal in Athletes.

Stress fractures of the fifth metatarsal (zones 2 and 3) remain a challenging clinical problem. It has been well established that nonsurgical treatment has unacceptably high nonunion and refracture rates. Surgical fixation remains the treatment of choice in the athletic cohort, and intramedullary screw fixation with a solid screw has been established as the most predictable means of achieving a successful outcome. Recently, the use of a plantar plate has also been advocated as has been shown in some studies to be more biomechanically advantageous. The use of bone grafting at the primary surgery and morphology and screw type are also important decisions to be made when treating these patients. This review will discuss our management of both primary fractures and refractures of the fifth metatarsal in athletes.

Cellulase production from Trichoderma reesei RUT C30 induced by continuous feeding of steam-exploded Miscanthus lutarioriparius

The production of low-cost and high-activity cellulase is crucial to the industrial development of biorefinery but has been undermined by the effective utilization of inducers. In this study, a solid screw feeder was designed and used to feed steam-exploded lignocellulosic biomass continuously for cellulase induction and production from Trichoderma reesei RUT C30. The results showed that continuous feeding of lignocellulosic inducers led to high activity of cellulase production than batch and intermittent fed-batch feeding. In particular, a promising second-generation energy crop, Miscanthus lutarioriparius, was found to be a much better inducer than other types of biomass. It resulted in filter paper activity of 19.85 FPU/mL when this material was feed continuously during fermentation. The feeding parameters were further optimized so that this feeding strategy and the utilization of the Miscanthus biomass combined can provide a potentially useful system for effective industrial cellulase production.

A Multicenter Retrospective Cohort Study of First Metatarsophalangeal Joint Arthrodesis

In this multicenter study, we evaluated commonly used methods of fixation and 2 methods of joint preparation for first metatarsophalangeal joint fusion, in terms of radiological union and revision rates. Included were 409 consecutive fusions in 385 patients. The overall union rate was 91.4% (34/409). About 29.4% (10/34) of our nonunions were symptomatic. Preoperative hallux valgus showed a statistically significant relation to nonunion (odds ratio [OR] = 9.33, p = .017). Other potential contributing factors like gender (OR 1.9, p = .44), diabetes (OR = 0, p = .99), steroid use (OR = 2.07, p = .44), inflammatory arthritis (OR = 0, p = .99), and smoking (OR = 2.69, p = .34) did not attain statistical significance. Further, the methods of fixation like solid screws (OR = 0, p = .99), plate (OR = 3.6, p = .187), or cannulated screws (OR = 0.09, p = .06) showed no correlation with incidence of nonunion. We compared 2 techniques of joint preparation and found no significant difference in union rates (chi-square = 1.0426, p = .30). Our crude comparison of costs showed the average saving to the trust per year could be 33,442.50£ by choosing screws over plates. To conclude, only hallux valgus had a statistically significant relation to nonunion. All other variables had no significant impact on the union. Solid screw seems to be economically the most viable option and a valid alternative.

Outcomes of Operatively Treated Jones Fractures in Major League Soccer Athletes

Objectives:Proximal 5th metatarsal fractures in athletes are common and have been studied in NCAA athletics as well as professional basketball (NBA), football (NFL), and European soccer (UEFA). Given that Jones fractures have not been studied in Major League Soccer (MLS), we sought to: (1) quantify the burden of fractures, (2) compare outcomes, re-fracture rates, and complication rates with other professional sports, (3) analyze factors for treatment failure, and (4) report return to play characteristics.Methods:A HealtheAthlete (Cerner Corporation, North Kansas City, MO) database was used to catalog all MLS injuries including and after the 2012 season. We extracted all possible Jones fracture injuries from these data from the 2013 to 2017 seasons (January 1, 2013 through December 31, 2017) using key words “toe,” “Jones,” “metatarsal,” “fracture,” and “fifth.” Over 12,000 unique injuries were cataloged; 141 were initially further investigated. Eighty-four were deemed benign, leaving 57 injuries; 12 were reported twice and 3 had 2 different dates of injury, leaving 42 injuries. We then contacted each team chief medical officer for more information including: demographics, date and mechanism of injury, injury classification (zone), prior or contralateral injury, limb dominance, imaging, operative vs. non-operative treatment, details regarding operative treatment if relevant, time to radiographic healing, time to return to sport, and complications including known re-fracture. Twenty-one injuries were further excluded, leaving 21 operatively treated Jones fractures in 18 players.Results:We analyzed 21 operatively treated Jones fractures in 18 players over the five-year study period. Fracture incidence was 0.37 ± 0.08 fractures per 1000 game exposure hours, or 0.063 ± 0.014 fractures per 1000 total exposure hours. Average age, weight, height, and BMI of players at time of fracture was 25.0 ± 3.7 years, 171.3 ± 17.2 lbs, 70.6 ± 3.2 inches, and 24.2 ± 1.9, respectively. 73.7% of players were right foot dominant, and 52.4% of players had right-sided injuries; 1 player reported bilateral injuries. Player position was reported as predominantly defense, midfield, or forward 44.4%, 16.7%, and 28.9%, respectively. 38.1% of injuries occurred in pre-season, with 38.1% associated with chronic, worsening pain, 23.8% with a rolled ankle/foot, 23.8% with a traumatic event, and 14.3% with a quick cut or pivot. One player reported concomitant medial sesamoiditis, otherwise there were no reported associated injuries. Five (24%) reported a prior contralateral fracture. Two (10%) reported a prior ipsilateral non-operatively treated stress fracture. Zone 2 injuries represented 81% of fractures, with the rest classified as zone 3. Average time into MLS career was 2.6 seasons; 8 (38%) occurred in the rookie season. Re-fracture rate was 4/18 players (22.2%), with 1 player’s initial fracture outside the study period; 2 players re-fracture occurred within the study period; and 1 player sustained a re-fracture while on loan (primary fracture included in the study). Average time to re-fracture was 390 days. Treatment for primary fractures (n = 18) included solid screw fixation in 11, cannulated screw fixation in 3, headless cannulated screw fixation in 3, and plate fixation with bone autograft in 1. Treatment for re-fractures (n = 3) included screw exchange with BMAC for 1, screw exchange and bone scaffold with PDGF in 1, and BMAC injection alone with bone stimulator for 1. Average time to radiographic union was 8.3 weeks. Average time to return to play was 10.4 weeks with one outlier removed. Complications include 4 re-fractures, 1 player with screw irritation who required exchange to headless screw with BMAC at 4 months post-op before return to play, 1 mild soft tissue irritation, and 1 mild persistent drainage that resolved with antibiotics. Overall, 20/21 (95%) of players returned to play. Currently, 5 players are retired, 7 remain in MLS, and 6 play in other worldwide professional leagues. Retired players averaged 2.8 years of play after injury. Player return to play characteristics were examined, including games played, games started, full games played, and minutes played; no statistical differences were found.Conclusion:Incidence of Jones fractures appears to be about 1.7x higher than previously reported in European professional soccer (UEFA) (Ekstrand and van Dijk Br J Sports Med 2013). However, articles examining Jones fractures incidence in NFL have shown increased prevalence in the NFL combine over the past few decades (Low et al J Surg Orth Adv 2004, Tu et al FAI 2018, Spang et al OJSM 2018). A significant number of injuries occur in pre-season (38%) and in players’ rookie seasons (38%), with the majority playing non-midfield positions. Return to play of 95% and re-fracture rate of 22% are comparable to rates in other professional sports. There does not appear to be any detrimental effect on players’ ability to perform after Jones fracture fixation.

Design and evaluation of a modularized ankle-foot orthosis with quick release mechanism.

Ankle foot orthosis (AFO) stiffness affects ankle range of motion but can also provide energy storage and return to improve mobility. To perform multiple activities during the day, a person may want to change their AFO stiffness to meet their activity's demand. Carrying multiple AFOs and changing AFOs is inconvenient and could discourage users from engaging in multiple activities. This project will develop a new quick-release mechanism (QRM) that allows users to easily change posterior strut elements to change AFO stiffness. The QRM attaches to the AFO and requires no tools to operate. The proposed QRM includes a quick-release key, weight-bearing pin, receptacle anchor, and immobilization pin. A prototype was modelled with SolidWorks and simulated with SolidWorks Simulation. The QRM was designed to have no mechanical failure during intense activities such as downhill walking and jogging. Unlike a solid screw connection, the QRM needed an additional part to eliminate unsecured motion related to clearance between the quick release key and receptacle anchor. Mechanical test results and measurement data proved no deformation on each part after mechanical testing.Clinical Relevance- The quick release AFO has the potential to improve user's activities range by tuning from stiffness free mode to high stiffness mode.

Radiographic Evaluation of Patients Submitted to Percutaneous Fixation With Solid Screw for Distal Radius Fracture Treatment.

Objective The present paper aims to present results from radiographic evaluations of patients with extra-articular distal radius fractures submitted to percutaneous fixation with a 3.5 mm solid screw. Methods Analytical, descriptive and retrospective case series of 16 patients with evaluation of the radiographic parameters. Results The average age of the study population was 46.5 years old (25–60 years old); 81.25% of the sample was female. The average time until surgery was 8.8 days (4–14 days). The mean preprocedural volar tilt was - 7.41° (−23.48°–5.29°, standard deviation [SD] ± 6.59°). The mean volar tilt immediately after surgery was 5.93° (SD ± 6.23°, p < 0.001). There was no statistical difference in volar tilt values after 6 months of follow-up. The mean preprocedural radial height was 4.13 mm (−7.8 mm–9.5 mm, SD ± 5.06 mm). There was a statistically significant increase at the immediate postoperative period to 10.04 mm ( p = 0.002), and a significant reduction at 6 months to 9.55 mm ( p = 0.012). The consolidation rate was 100% with the technique used, with a minimal complication rate. No patient had infection or required a reoperation. Conclusion The technique was effective for the treatment of distal radial extra-articular fractures at 6 months, with a low complication rate; radiographic parameters values were acceptable and close to the anatomical ones.

Intralaminar Screw Fixation of Spondylolysis.

Spondylolysis, defined as injury to the pars interarticularis, is the most common identifiable cause of back pain in children. Historically, treatment has primarily been nonoperative, including physical therapy, activity modification, and occasionally bracing1. In instances in which the condition is refractory to nonoperative management, however, surgical treatment may be an efficacious alternative. Persistent pain following nonoperative management is described as occurring in 6% of the general population, but is reported to be as high as 15% to 47% in the pediatric population who participate in sports2,3. There have been several proposed methods of surgical intervention, such as screws, hooks, wires, and combinations of the aforementioned, none of which have garnered unanimous support as being most effective. The report by Buck3 served to popularize the use of intralaminar screwing for fixation, and the 93% success rate reported in that study has since been corroborated, with several studies reporting rates from 82% to 100%1,3,4. This technique offers a low-profile solution that is motion-sparing with demonstrable stability and mechanical advantage compared with other techniques5 and has been shown to be a more stable method of fixation that can correct relatively large defects, showing efficacy with defects 4 mm and larger5. This procedure is performed by (1) placing the patient in a prone position with minimization of lordosis on the operating table and use of fluoroscopy to localize the defect. (2) A midline incision (approximately 5 cm) is made just lateral to the corresponding spinous process in order to expose the lamina and the defect. (3) A curet is used to clean the defect. (4) Under fluoroscopy, and alternating between anteroposterior and lateral views, a percutaneous stab is made if needed using a 4.5-mm cannulated screw guidewire, and the wire is drilled through the caudal laminar surface, bisecting the pedicle to the superior cortex of the pedicle. (5) A 3.2-mm cannulated drill is then used to drill over the guidewire. (6) The wire is removed, and a ball-tip probe is used to feel the cortices. The screw length is measured and tapped. (7) The lamina is distally overdrilled if it is large enough. (8) A solid (rather than cannulated) screw of appropriate size (usually 4.5-mm diameter) is inserted with compression as needed. (9) If necessary, autologous posterior iliac crest bone graft is obtained from the same incision, and cancellous graft is placed in the defect. (10) A corticocancellous strip is overlaid from the lamina to the transverse process.

PO 18145 - Anatomical structures at risk in proximal fifth metatarsal fracture fixation

Introduction: Proximal fifth metatarsal fracture fixation is usually treated conservatively, but when chosen for surgical treatment, percutaneous fixation with screws is the most used. This study aims to evaluate the presence of injury of the structures at risk and to measure the distance of these structures to the entry point. Methods: Eleven fresh-frozen below-the-knee specimens underwent standard operative fixation for a Jones fracture via the “High and inside” percutaneous technique. A guide wire was placed through the medullary canal and confirmed on fluoroscopy. The cannulated drill with a drill sleeve was then placed over the wire and advanced to the diaphysis. The guide wire was left, and the skin and subcutaneous tissues were carefully removed from the lateral midfoot to fully expose the structures at risk. The guidewire was then removed, and then the solid screw was placed. Neurovascular and tendinous structures were assessed for any injury. The distance of the wire in the base of the fifth metatarsal and these structures was measured and documented, including the branches of the sural nerve, cuboid, fourth metatarsal, peroneus longus, and peroneus brevis tendons. Results: The structure with the shortest average distance from the pin was the peroneus brevis, measuring 0.91 mm (±1.22 mm S.D.), followed by the cuboid articular surface, sural nerve, peroneus longus, and base of the fourth metatarsal, respectively. The pin had damaged the peroneus brevis in 5 of 11 cadavers. The average distance from the tendon insertion point was 7.2 mm. The furthest measured distance was 10 mm, while the closest was 3 mm. The screw head contacted the articular surface of the cuboid in 3 of 11 cadavers. There were no instances of pin contact with or damage to the peroneus longus, sural nerve, or fourth metatarsal head. Conclusion: We conclude that percutaneous fixation of fractures of the base of the fifth metatarsus presents a risk of partial lesion of the peroneus brevis tendon and lateral aspect of the cuboid. Therefore, specific care with these structures should be taken during the procedure.

Anatomical Structures at Risk in Proximal Fifth Metatarsal Fracture Fixation: A Cadaver Study

Category:Sports, Trauma, Cadaver studyIntroduction/Purpose:Jones fractures are fractures of the proximal fifth metatarsal involving the metaphyseal-diaphyseal junction. They have an increased risk for refracture, delayed union and nonunion secondary to poor blood supply to this área. They are usually treated conservatively, but when chosen for surgical treatment percutaneous fixation with screws is the most used. Few studies have evaluated the complications of injury to nearby structures during the percutaneous fixation. It has been shown, however, that the peroneal brevis and longus, the cuboid, and the sural nerve lie in close proximity to this starting point and are, therefore, at theoretical risk of injury. The study aims to evaluate the presence of injury of the structures at risk and to measure the distance of these structures to the entry point.Methods:Eleven fresh-frozen below-the-knee specimens underwent standard operative fixation for a Jones fracture via the “High and inside” percutaneous technique. A guide wire was placed through the medullary canal and confirmed on fluoroscopy. The cannulated drill with drill sleeve was then placed over the wire and advanced to the diaphysis. The guide wire was left and the skin and subcutaneous tissues were carefully removed from the lateral midfoot to fully expose the structures at risk. The guidewire was then removed, and then the solid screw was placed.Neurovascular and tendinous structures were assessed for any injury. The distance of the wire in the base of fifth metatarsal and these structures was measured and documented, including the branches of the sural nerve, cuboid, fourth metatarsal, peroneus longus, and peroneus brevis tendons.Results:The structure with the shortest average distance from the pin was the peroneus brevis, measuring 0.91 mm (±1.22 mm S.D.), followed by the cuboid articular surface, sural nerve, peroneus longus, and base of the fourth metatarsal, respectively. The pin had damaged the peroneus brevis in 5 of 11 cadavers. However, it did not damage at the tendon insertion point in any specimen. The average distance from the tendon insertion point was 7.2 mm. The furthest measured distance was 10 mm, while the closest was 3 mm. The screw head contacted the articular surface of the cuboid in 3 of 11 cadavers. There were no instances of pin contact with or damage to the peroneus longus, sural nerve, or fourth metatarsal head.Conclusion:This is the only study that evaluated the risk of injury the structures after a procedure that simulated an actual surgical act. It is also the only one that was aware of the risk of tendon injury not only in its insertion but also in its path during the placement of the wire and drill. We conclude that percutaneous fixation of fractures of the base of the fifth metatarsus presents a risk of partial lesion of the peroneus brevis tendon and lateral aspect of the cuboid. Therefore, specific care with these structures can be taken during the procedure.

Performance Assessment of Screw Piles Embedded in Soft Clay

Screw piles are widely used in a variety engineering applications supplying stability against compression, overturning moment, uplift tension, and horizontal loads. Screw pile is a famous solution for support light structures, roads and rail signs which have relatively low-capacity foundation. In this study, the behavior of circular (10) mm solid screw pile models embedded in a bed of soft clay soil covering a layer of sandy soil has been studied. The 200 mm thick sand layer was compacted in a steel container with a diameter of 300 mm into four sublayers. The sandy soil layer was compacted at a relative density of 70%. The 300 mm thick soft clay soil bed with Cu (30) kPa was compacted in six sub-layers on the sandy bottom layer. Model tests are carried out with screw piles with a length of 300 mm, 350 mm and 400 mm and a helix diameter of 30 mm. Also, single and double helix and different S/Dh ratio were used for these piles and a comparative study between screw piles and ordinary piles (without helices) is accomplished. This study revealed that introducing screw pile of double helix increases its bearing capacity in soft clay soil by up to a (4-8) % as compared to a single helix screw pile. The results showed that the behavior of screw pile essentially depends on the geometric properties of the pile. According to the achievements, compressive load capacity of screw piles depends on embedded length, spacing ratio (S/Dh) and number of helical plates.

Cannulated Screws

The use of cannulated screws in foot and ankle surgery has increased over the years, but remains controversial and largely subject to surgeon preference. A research roundtable of questions has been submitted to 6 invited foot and ankle surgeons relative to their individual use of these cannulated devices. The purpose of this symposium is to explore some of the pertinent controversies between traditional solid screws and cannulated screws. With our current worldwide health care cost concerns, design, and manufacturing there will be a convergence in a quest for value in our implants. I am excited to have such an experienced and well-known group of foot and ankle surgeons participate in this dialogue. 1)Is there any situation in foot and ankle surgery where a solid screw cannot be used and you must use a cannulated?

Impact of Screw Type on Kyphotic Deformity Correction after Spine Fracture Fixation: Cannulated versus Solid Pedicle Screw.

Study DesignRetrospective review.PurposeTo detect the effect of cannulated (poly-axial head) and solid (mono-axial head) screws on the local kyphotic angle, vertebral body height, and superior and inferior angles between the screw and the rod in the surgical management of thoracolumbar fractures.Overview of LiteratureBiomechanics studies showed that the ultimate load, yield strength, and cycles to failure were significantly lower with cannulated (poly-axial head) pedicle comparing to solid core (mono-axial head).MethodsThe medical charts of patients with thoracolumbar fractures who underwent pedicle screw fixation with cannulated or solid pedicle screws were retrospectively reviewed; the subjects were followed up from January 2011 to December 2015.ResultsTotal 178 patients (average age, 36.1±12.4 years; men, 142 [84.3%]; women, 28 [15.7%]) with thoracolumbar fractures who underwent surgery and were followed up at Hamad Medical Corporation were classified, based on the screw type as those with cannulated screws and those with solid screws. The most commonly affected level was L1, followed by L2 and D12. Surgical correction of the local kyphotic angle was significantly different in the groups; however, there was no significant difference in the loss of correction of the local kyphotic angle of the groups. Surgical correction of the reduction in the vertebral body height showed statistical significance, while the average loss of correction in the reduction of the vertebral body height was not significantly different. The measurement of the angles made by the screws on the rods was not significantly different between the cannulated (poly-axial head) and solid (mono-axial head) screw groups.ConclusionsSolid screws were superior in terms of providing increased correction of the kyphotic angle and height of the fractured vertebra than the cannulated screws; however, no difference was noted between the screws in the maintenance of the superior and inferior angles of the screw with the rod.

Radiographic Results and Complications of 3 Guided Growth Implants.

Temporary, implant-mediated hemiepiphysiodesis (ie, guided growth) is an effective and popular treatment method for lower extremity angular deformities. The purpose of this study was to retrospectively evaluate the safety profile of 3 different implants used to correct lower extremity angular deformities in pediatric patients. We retrospectively reviewed a consecutive series of pediatric patients with lower extremity angular deformities who underwent implant-mediated guided growth by 2 surgeons at our institution between 2004 and 2014. Implants were selected according to surgeon preference and included the Biomet peanut plate, Orthofix eight-plate, and Pega Medical hinge plate. Medical records and radiographs were reviewed to assess deformity correction, implant integrity, and complications. During the study period, 115 plates (63 Biomet peanut plates, 30 Orthofix eight-plates, and 22 Pega Medical hinge plates) were implanted in 52 patients (24 males, 28 females). Average age at implantation was 11.7 years (12.3 y in males, 11.1 y in females). Average length of follow-up was 18.4 months. There was no significant difference in rate of deformity correction between the implant types (P=0.08).Three broken screws (2.6%) were observed, all of which involved cannulated screws in peanut plates. Four peanut plates (6.3%) had an implant-related complication: 3 broken screws and 1 screw pullout. Three eight-plates (10.0%) had screw pullout. No complications were observed within either the hinge plate or solid screw groups. Implant-related complications were significantly associated with increased body weight and cannulated screw use (P=0.02 and 0.03, respectively), but not bone age, sex, plate type, or rate of deformity correction. No deep infections, premature growth arrests, or plate breakages were observed. Implant-mediated guided growth is a safe technique for pediatric lower extremity angular deformity correction with a low complication rate. This study demonstrated that overweight patients had a significantly higher rate of implant-related complications. Screw breakages were only observed with cannulated screws in peanut plates. Thus, we recommend using solid, noncannulated screws in overweight children who are at an increased risk of implant failure. Level IV-retrospective case series.