Screw Group Research Articles

Effect of additional free sustentaculum tali screw fixation through modified sinus tarsi approach on intra-articular calcaneal fractures

BackgroundCalcaneal fractures are the most common type of tarsal fractures. The sustentaculum tali (ST) offers anatomical stability in calcaneal fractures, and recently, ST screws have been widely used in their treatment. This study aimed to investigate the clinical efficacy and value of ST screw fixation via a modified sinus tarsi approach (MSTA) for treating displaced intraarticular calcaneal fractures (DIACFs).MethodsThis study enrolled 64 patients (64 feet): 32 patients in the calcaneal locking plate combined with the ST screw group (CLP-STS Group) and 32 patients in the simple calcaneal locking plate internal fixation group (CLP Group). The minimum follow-up duration was 18 months. Ankle function was evaluated using VAS, AOFAS, and Short Form-36 scores. Imaging evaluation included the Böhler angle, Gissane angle, length, height, and width of the calcaneus, and the Böhler angle in both groups 1 year after surgery.ResultsFunctional evaluation revealed that postoperative AOFAS and VAS scores in the CLP-STS Group were significantly better than those in the CLP Group. After surgery, the Böhler angle, Gissane angle, and length, height, and width of the calcaneus were significantly corrected compared to the preoperative values; however, the difference in these indicators between the two groups was not significant. Nevertheless, at the 1-year postoperative follow-up, the calcaneal Böhler angle loss in the CLP-STS Group was significantly better than that in the CLP Group.ConclusionCompared to simple calcaneal locking plate internal fixation, combining the plate with the additionally free ST screw can resolve the limited intraoperative exposure of MSTA, reduce postoperative foot pain in patients, and improve clinical efficacy.

Comparison of plate and compression screw in the treatment of hallux rigidus with arthrodesis: a retrospective study

Objectives: Although numerous surgical techniques and fixation methods have been described for the treatment of hallux rigidus (HR) with arthrodesis, consensus on the gold standard treatment has not been reached. The aim of this study is to retrospectively compare the clinical and radiological outcomes of compression screw fixation and plate fixation in the treatment of HR with arthrodesis. Methods: Patients who underwent arthrodesis surgery due to HR between January 2021 and December 2023 at a single center were retrospectively reviewed. Patients who met the inclusion criteria were divided into two groups: those who underwent arthrodesis with plate fixation (PLATE) and those who underwent arthrodesis with compression screw fixation (SCREW). Demographic data including age, gender, affected side, operative time, hallux valgus angle (HVA), dorsiflexion angle, AOFAS scores, and implant irritation data were compared among patients with at least 3 months of follow-up. Results: It was observed that all patients included in the study had successful bone union without any complications. There were no significant differences between the two groups in terms of age, gender, affected side, preoperative HVA, and preoperative AOFAS scores (P=0.970, P=0.426, P=0.694, P=0.216, and P=0.905, respectively). The mean operation time and postoperative AOFAS score were lower in the PLATE group compared to the SCREW group (P=0.006 and P=0.004, respectively). However, in the SCREW group, the dorsiflexion angle and the rate of implant irritation were lower compared to the PLATE group (P=0.016 and P=0.01, respectively). Conclusions: In the surgical treatment of HR, both plate fixation arthrodesis and compression screw arthrodesis are reliable surgical techniques. While plate fixation arthrodesis is a faster and more practical method, arthrodesis with a compression screw results in fewer complaints related to the implant and provides a more functional recovery.

Effect of screw insertion depth into fractured vertebrae in the treatment of thoracolumbar fractures

PurposeThe study’s objective was to assess the effect of the screw insertion depth into fractured vertebrae in treating thoracolumbar fractures.Materials and methodsThis was a retrospective analysis of 92 patients with thoracolumbar fractures from December 2018 to February 2020. Patients had AO type A2, A3 thoracolumbar fractures. The patients were divided into two groups according to the screw insertion depth. The vertebral wedge angle (VWA), Cobb angle (CA), anterior vertebral body height (AVBH), middle vertebral body height (MVBH), visual analog scale (VAS) score, and Oswestry Disability Index (ODI) were compared preoperatively and at one week and 12 months postoperatively. The correlation between Vertebral height loss and potential risk factors, such as sex, age, BMD and BMI was evaluated.ResultsCompared with the preoperative data, the postoperative clinical and radiographic findings were significantly different in both groups, But no significant difference between the two groups at 1 week. At 1 year postoperatively, there was a significant difference in the CA (p < 0.0001), VWA (p = 0.047), AVBH (p < 0.0001), MVBH (p < 0.0001), VAS score (p < 0.0001), and ODI (p < 0.0001) between the two groups, Except for age, bone density and other influencing factors the long screw group had better treatment results than the short screw group.ConclusionA longer screw provides greater grip on the fractured vertebral body and stronger support to the vertebral plate. The optimal screw placement depth exceeds 60% of the vertebral body length on the lateral view.

Biomechanical Performance of 4-Leg Sustained Dynamic Compression Staples in First Tarsometatarsal Arthrodesis.

This study investigates the biomechanical efficacy of new 4-leg Sustained Dynamic Compression (SDC) NiTiNOL staples, hypothesized to offer superior stability and resilience to loading before fusion completion, compared with conventional hardware. Twenty sawbones left full foot models were divided into 4 treatment groups: (1) 4-leg Inline Staple, (2) 4-leg Inline Staple + 2-leg Staple, (3) 4-leg Inline Staple + Screw, and (4) Plate + Screw. An osteotomy was performed to simulate a Lapidus procedure, and the respective fixation methods were applied. Mechanical testing was conducted using a servo-hydraulic testing machine to evaluate constructs' load, contact force, contact area, and plantar gap. The 4-leg Inline Staple + Screw group demonstrated significantly increased joint contact force, joint contact area, and decreased plantar gap compared with the Plate + Screw group, both before and after cyclic testing. All SDC-containing constructs exhibited post-cyclic joint contact areas that were 2.36×, 3.87×, and 5.49× greater than the post-cyclic plate + screw group. Most notably, the 4-leg Inline Staple + Screw group maintained a plantar gap of less than 3 mm throughout the testing, unlike other groups. The 4-leg Inline SDC Staple, particularly when combined with a static screw, demonstrated biomechanical superiority over traditional plate and screw constructs in Lapidus procedures. These findings suggest a promising avenue for enhanced post-operative stability, which could translate into quicker patient recovery, improved fusion rates, and potentially lower non-union rates. Further clinical trials are warranted to validate these biomechanical advantages in patient outcomes. Therapeutic, Level V: Bench Testing.

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.

What Is the Optimal Method of Fixation for Scaphoid Nonunion Relative to the Location of the Lesion?

Scaphoid nonunion is a typical complication of scaphoid fractures, with the nonunion rate varying by the location of the scaphoid. The current widely used method for treating scaphoid nonunion, which is challenging for surgeons, is the headless compression screw (HCS). Various surgical approaches, such as the scaphoid plate, have been proposed to address the problem of screw fixation; however, no consensus exists regarding the optimal treatment method. This study focused on analyzing appropriate treatment methods based on the anatomical location of the scaphoid nonunion. Ninety-seven patients with scaphoid nonunion were treated between 2008 and 2023. All patients underwent treatment using 1 HCS or scaphoid volar locking plate with nonvascularized bone graft from the distal radius depending on the scaphoid's location. The scaphoid angle and bone union were confirmed using radiological examinations. The clinical evaluations included range of motion, pain, grip strength, and functional wrist scores. Fifty-seven patients were included in the final analysis. In the screw group, 26 patients (26/42 [62%]) obtained a bone union, and all 15 patients (15/15 [100%]) in the plate group obtained a union ( P = 0.005). In the waist group, 16 patients with screw (16/25 [64%]) and 8 using a plate (8/8 [100%]) showed bony healing. In the proximal group, 3 patients with HCS (3/9 [33%]) and 4 using plate (4/4 [100%]) showed bone union. In the distal group, 7 patients with a screw (7/8 [87%]) and 3 with the plate (3/3 [100%]) showed bone union. Significant differences were found in the waist ( P = 0.047) and proximal groups ( P = 0.026), but not in the distal group ( P = 0.521). All groups showed improved radiological angles associated with the scaphoid and better clinical outcomes postoperatively. Plate fixation was overall superior to screw fixation for scaphoid nonunion, especially in the waist and proximal poles, providing better union rates and stability. For the distal group, both methods are effective, with the choice depending on the surgeon's expertise and patient factors. The results highlight the importance of the lesion's anatomical location in selecting the appropriate fixation method.

Study on the tightening scheme of electronic component screw assemblies based on finite element simulation

Abstract To improve the fastening effect of electronic components in mechatronic equipment, the tightening sequence and frequency have a significant impact on the structural performance of these components. This study identifies an optimal fastening method through experimental verification, although some measurement errors were noted; the method remains highly reliable. First, theoretical calculations and experimental analyses were conducted to determine the torque values under different conditions. Then, simulations were performed to study the impact on the stress of each screw. Finally, experimental validation of the simulation results was carried out, and a linear relationship (with a value of 0.82) between the measured and theoretical values was explored. Consequently, an optimized screw group fastening method is proposed, and the torque calculation process is simplified, thereby enhancing the reliability and lifespan of electronic components in mechatronic systems.

Elastic nail versus plate for treatment of single close fracture of femur shaft

This study aims to describe the outcome of pediatric flexible nails versus plates for the treatment of femur fracture. We reviewed the medical records of 28 femur fractures in children treated with flexible nail insertion and 26 children treated with plate fixation from January 2017 to December 2019. The mean age of the children was 8.88 ± 1.86 years. Data were obtained from patient charts. Union of bones was found in all the operated children, 28 (51.9%) of the group flexible nails, while no union was found in 3 (5.6%) of the group plate with screws. Delay union was found in 5 (9.3%) of the plate with screws, while in the group of flexible nails was in 2 (3.7%). Malrotation was found in 2 (3.7%) of the flexible nails and in 1 (1.9%) in the plate and screw. Bursa was found only in the flexible nails with 7 (13%) (p = 0.007). Re-fracture was found only in the group of plates with screws with 5 (9.3%) (p = 0.021). The limbs were shortened only in 1 (1.9%) patient with flexible nails. Superficial infection was high in the group plate with screws group 4 (7.4%). Deep infection was found to be high among 3 (5.6%) of the group plate &amp; screw. We conclude that flexible intramedullary nail fixation of fracture shaft femur in children is a very acceptable way of treatment and is associated with minimal complications.

Clinical value and risk factors of compression supporting screwsin patients with femoral neck fractures

BackgroundThis study was performed with attempt to explore the clinical value and risk factors of compression supporting screws for the treatment of femoral neck fractures.MethodsThis retrospective analysis enrolled 102 patients with femoral neck fractures who admitted to our hospital from June 2020 to June 2022. Based on different screws during the operation, the participants were allocated into hollow screw group (52 cases, conventional fixation of parallel partial-thread hollow screw) and compression screw group (50 cases, compression screw fixation).ResultThe incidence of complications (including internal fixation failure, nonunion, a vascular necrosis of the femoral head, shortening of the femoral neck by less than 10 mm, and lateral screw withdrawal, of the affected limb) in the compression screw group were significantly lower than those in the hollow screw group (P < 0.05). Patients enrolled in this study were followed up for 9 to 14 months, with an average follow-up time of (12.09 ± 1.87) months.The pain degree at 3 days, 10 days, and the last follow-up after operation in the compression screw group was evidently lower than that in the hollow screw group (P < 0.05). At the last follow-up, the improvment in hip joint function was more significant in the compression screw group than in the hollow screw group (P < 0.05). Univariate logistic regression analysis showed that the risk factors for complications in the treatment of femoral neck fractures with compression supporting screws were age, Pauwels type III fracture (modified Pauwels classification), and hip joint (≥ 90 points). In addition, the result of multivariate logistic regression analysis showed that the risk factors for complications in the treatment of femoral neck fractures with compression supporting screws were age, Pauwels type III fracture (modified Pauwels classification).ConclusionOur findings demonstrated beneficial outcomes obtained by using compression supporting screw, in terms of effectively enhancing the recovery of patients with femoral neck fracture and reducing the associated complications.

A simple modified technique for screw fixation of displaced intra-articular calcaneus fracture through a sinus tarsi approach: a comparison with plate fixation

BackgroundPlates and screws are frequently used for the fixation of displaced intra-articular calcaneus fracture (DIACF). In this study, we compared the outcomes of a modified screw fixation technique with plate fixation via a sinus tarsi approach (STA).MethodsA series of 187 DIACF patients who were treated via an STA using a plate fixation (n = 81) or a screw fixation (n = 106) were included. Screw fixation was done with two 2.7 mm screws and two 6.5 mm cannulated screws. Outcomes were evaluated radiographically and clinically. Clinical evaluations included pain assessment by Visual Analogue Scale (VAS) and functional assessment by the American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire and Foot Function Index (FFI).ResultsThe mean final VAS was smaller in the screw group (P = 0.01). The mean AOFAS and FFI scores were not significantly different between the two groups (P = 0.17 and P = 0. 19, respectively). The mean improvement of Bohler’s angle, but not the Gissane’s angle, was significantly greater in the screw group (P = 0.014 and P = 0.09, respectively). The mean improvement of calcaneal length and height were not significantly different between the two groups (P = 0.78 and P = 0.22, respectively). The hardware removal rate was 14.8% in the plate group and 3.8% in the screw group (P = 0.007).ConclusionThe modified screw fixation method provides lower pain, better radiographic outcome, and lower rate of hardware removal compared to plate fixation in the treatment of DIACF.

Outcomes of Traditional Dual Growing Rods With Apical Control Techniques for the Treatment of Early-Onset Scoliosis: Comparison With Patients Treated With Traditional Dual Growing Rods Only With a Minimum 2-Year Follow-up After Graduation.

Correction with traditional dual growing rods (TDGR) might not be sufficient for severe and rigid spinal deformity. TDGR combines with apical control techniques (ACT) could theoretically improve curve correction and decrease the incidence of mechanical complications. However, long-term results for TDGR with ACT are limited. The aim of this study was to retrospectively review and compare the outcomes of patients who graduated from TDGR with or without ACT. Patients who were treated by TDGR with or without ACT with a minimum 2-year follow-up after graduation were enrolled. According to the intervention for the apex, patients were further divided into the TDGR group, the TDGR + apical control pedicle screws group (without apical fusion), and the TDGR + hybrid technique group. Clinical outcomes, radiological parameters, pulmonary function, and complications were compared among the 3 groups. A total of 76 patients (51 patients in the TDGR group, 10 patients in the apical control pedicle screws group, and 15 patients in the hybrid technique group) were enrolled. Compared with TDGR, TDGR + ACT achieved better main curve correction, better control of apical vertebral translation and rotation, and lower incidence of complications and revision surgery (P < .05) while maintaining development of the spine and chest. Although the difference was not significant, patients in the TDGR + ACT group had better pulmonary function at the last follow-up (P > .05). The percentage of patients receiving final fusion in the TDGR + ACT group was significantly lower than that in the TDGR group (P < .05). Compared with TDGR, TDGR + ACT can achieve better curve correction and apical control and comparable clinical outcomes while maintaining the growth of the spine and chest. Patients may derive more benefits from treatment with TDGR + ACT, including a lower incidence of mechanical complications and revision surgery, better pulmonary function, and the avoidance of final fusion.

Three-Dimensional Printing Technology Based on Digital Orthopedics: 5-Point Positioning Point-Contact Pedicle Navigation Template in the Case of Scoliosis and Complex Pedicle.

Imperfect fitting of the navigation template leads to prolonged surgery time and increased blood loss. These problems have not been effectively addressed in previous research. This study explores the efficacy of a novel 5-point positioning point-contact pedicle navigation template in complex pedicle situations in scoliosis. This study employed a retrospective controlled design. From November 2019 to November 2023, 28 patients with scoliosis and complex pedicle were selected and underwent scoliosis correction surgery. A 5-point positioning point-contact pedicle navigation template was used intraoperatively to guide pedicle screw placement. Matched with 56 historical cases as a control group. The analysis included screw placement time, screw placement bleeding volume, fluoroscopy frequency, manual repositioning frequency, screw placement accuracy and grade, screw placement complications, and main curve correction rate. Continuous variables were compared using the independent samples t-test. Categorical data were analyzed with the chi-square test. All 28 patients successfully underwent surgery, with a total of 268 pedicle screws placed. The surgery duration ranged from 220 to 410 min, with an average of (283.16 ± 51.26) min. Intraoperative blood loss ranged from 630 to 1900 mL, with an average of (902.17 ± 361.25) mL. Pedicle screw placement time ranged from 60 to 130 min, with an average of (85.24 ± 24.65) min. Pedicle screw placement bleeding volume ranged from 40 to 180 mL, with an average of (76.47 ± 42.65) mL. Fluoroscopy frequency ranged from 3 to 7 times, with an average of (4.31 ± 1.14) times. Manual repositioning frequency ranged from 0 to 2 times, with an average of (0.46 ± 0.58) times. Pedicle screw placement grades: Grade I: 237 screws; Grade II: 25 screws; Grade III: 6 screws; Grade IV: 0 screws. There were no screw-related complications. The correction rate ranged from 46% to 68%, with an average of (55.83 ± 9.22)%. Compared to the experienced screw group, the differences in screw placement time, screw placement bleeding volume, fluoroscopy procedures, and manual redirections were statistically significant (p < 0.05). The 5-point positioning point-contact pedicle navigation template features a claw-like structure that securely adapts to various deformed vertebral facet joints, avoiding drift phenomena and ensuring accurate screw placement. Its pointed contact structure with the lamina of the spine avoids extensive and complete detachment of posterior structures, reducing blood loss, surgery time, and trauma. Predesigned pedicle screw entry points and directions reduce fluoroscopy frequency and surgery time.

Clinical and biomechanical comparison of suture-external button versus interference screw associated with V-Y advancement or turndown flaps for flexor hallucis longus transfer in chronic Achilles tendon rupture.

Surgical treatment of chronic Achilles tendon rupture is a technically challenging procedure. We aimed to compare the clinical outcomes, range of motion, and strength of ankle plantar- and dorsiflexors between two techniques for fixation of flexor hallucis longus tendon to the calcaneus: interference screw and suture-external button. Twenty-five patients participated in this retrospective comparative study. All patients underwent short harvest FHL tendon transfer for chronic AT rupture were asked for a follow-up visit, at least one year following surgery. The outcomes were evaluated by visual analog scale (VAS), AOFAS ankle-hindfoot score, and VISA-A questionnaire. Ankle ROM with possible restriction in addition to isokinetic strength of ankle plantar- and dorsiflexors was assessed. No statistically significant difference was observed between the groups for pain (P = 0.81), AOFAS ankle-hindfoot scale (P = 0.97), and VISA-A (P = 0.44). Notably, more decrease in ankle dorsiflexion was seen in interference screw group in comparison with suture-external button group (4.4 ± 6.6 vs. 9.5 ± 6.1 degrees, P = 0.06). The difference of active dorsiflexion between operated and non-operated side in interference screw group was statistically significant (P = 0.02). Biotenodesis screw imposed more limb asymmetry in comparison with suture-external button technique. Fixation of transcalcaneal FHL tendon transfer for chronic AT either by interference screw or suture-external button has encouraging postoperative clinical results. Although ROM of the ankle joint reduced in both techniques, interference screw may result in more reduction in dorsiflexion of the ankle.

Clinical and radiographic outcomes using standard length of cannulated screws for traditional Latarjet procedure

PurposeThe purpose of this study was to evaluate the clinical and radiographic outcomes of open traditional Latarjet stabilization using 32mm and 30mm long cannulated screws in males and females respectively with a minimum of 2 years’ follow-up. MethodsWe retrospectively reviewed open Latarjet procedures using cannulated screws of standard length with a minimum of 2 years follow-up. Functional evaluation was performed with postoperative Rowe and Walch score, visual analogue scale for pain (VAS) and return to sport. Graft healing was assessed with CT scans at 4 to 6 months postoperatively. Patients were divided into 2 groups according to postoperative radiographic measurements: a bicortical or unicortical screw groups. The α angle between the shaft of the screw and the glenoid subchondral bone was measured for superior and inferior screws. Level of significance was 0.05. The post hoc power analysis was 0.89. ResultsA total of 69 patients met the criteria for inclusion. Of these patients, 60 (87%) were available for final follow-up (n =62 shoulders), with a mean age of 28.4 ±9.5 years (range, 16-55 years) at time of surgery. 56 males (93.3%) and 4 females (6.7%) were included. The mean final follow-up period was a mean of 38 months after the procedure (range, 25-48 months). 8 out 60 patients (13.3%) had persistent apprehension in abduction–external rotation position. One patient (1.7%) had a recurrence of shoulder subluxation. The mean Walch-Duplay score was 90±11.6 points (range, 40-100 points), and the mean Rowe score was 93.4±11 points (range, 50-100 points). The mean VAS score for the evaluation of pain was 0.9±1.3 (range, 0-4). The coracoid healed the glenoid neck in 87.1% (54/62) of the shoulders on the postoperative CT scan. Lower alpha angle for inferior and superior screws had more rate of unicortical fixation (P=0.05 and P=0.04, respectively). 14 out 62 (22.6%) shoulders were found unicortical screws. Six bicortical cases and 2 cases unicortical screws (25%) showed nonunion (p=0.86). There were 2 complications, one patient had hematoma that required drainage, one case had transient axillary nerve palsy which resolved spontaneously. No complications associated with the hardware were found. ConclusionOpen traditional Latarjet procedure using 32 mm and 30mm long cannulated screws in male and females respectively, provided good outcomes with acceptable complication rates. Unicortical screws fixation does not have a higher rate of non-union than bicortical screws.

Biomechanical differences of three cephalic fixation methods for patients with basilar invagination and atlantoaxial dislocation in the setting of congenital atlas occipitalization: a finite element analysis

Background contextIn cases of basilar invagination-atlantoaxial dislocation (BI-AAD) complicated by atlas occipitalization (AOZ), the approach to cranial end fixation has consistently sparked debate, generally falling into two categories: C1–C2 fixation and occipitocervical fixation. Several authors believe that C1–C2 fixation carries a lower risk of fixation failure than occipitocervical fixation. PurposeTo study the biomechanical differences among 3 different cranial end fixation methods for BI-AAD with AOZ. Study designThis was a finite element analysis. Patient sampleA 35-year-old female patient diagnosed with congenital BI-AAD and AOZ. Outcome measuresrange of motion (ROM), peak von Mise stress (PVMS), cage micro-subsidence, cage micro-slippage MethodFour finite element models were constructed, including unstable group (BI-AAD with AOZ), C1 lateral mass screw group, occipital plate group, occipitocervical rod group. The flexion and extension (FE), lateral bending (LB) as well as axial rotation (AR) were simulated under a torque of 1.5 Nm. Parameters include C1–C2 ROM, PVMS on screw-rod construct, cage micro-subsidence, cage micro-slippage. ResultsThe ROM of the C1 lateral mass screw group was smaller than that of the other fixation groups in LB and AR, but not FE. Compared with the occipitocervical rod group, the ROM in LB and AR of the occipital plate group was higher, but not in FE. The PVMS of C1 lateral mass screw group was significantly higher than that of the other groups. The ROM and PVMS of the occipitocervical rod group were in between the other 2 groups. Regarding the screws at the cranial end, the PVMS of the 4-screw occipitocervical rod group was significantly lower than that of the other groups. In general, the cage micro-motion follows the ascending order: C1 lateral mass group < occipitocervical rod group < occipital plate group. ConclusionIn cases of BI-AAD with AOZ, the C1 lateral mass screw group provided the least ROM and cage micro-motion, but the screw-rod PVMS was the largest. The advantage of occipital plate fixation lies in the lowest screw-rod PVMS, but the ROM and cage micro-motion is the highest. Four-screw fixation at the cranial end of occipitocervical rod group helps to reduce the PVMS and may prevent screw failure at the cranial end.

Distal blocking screw augmentation in ulnar intramedullary nail fixation of adult forearm diaphyseal fractures.

This study aimed to evaluate the effect of distal blocking screws on the stability and healing of ulnar diaphyseal fractures treated with intramedullary (IM) nails. The primary research question was whether the addition of distal blocking screws enhanced fracture stabilization and promoted faster healing than the standard IM nailing techniques. This retrospective study reviewed medical records of 30 patients with ulnar diaphyseal fractures treated from February 2018 to September 2023. The patients were divided into two groups: those treated using IM nails alone (n = 17) and those treated with using IM nails with distal blocking screws (n = 13). The surgical time, medullary canal space, fracture healing time, and complications were assessed. Functional outcomes were evaluated using the Grace and Eversmann rating system, the DASH scores, and the VAS scores. The addition of distal blocking screws resulted in a slightly longer surgical time (56min vs 47min). However, the group with distal blocking screws had smaller medullary canal space and showed significantly faster fracture healing times (2.3 months vs 3.9 months; p = .036). There were no reported complications of nonunion, nerve injury, or infection in the distal blocking screw group, whereas the IM nail-only group had one case of nonunion (5.7%). The use of distal blocking screws in conjunction with IM nails for ulnar diaphyseal fractures improves fracture stability and promotes faster healing.

Miniplates versus Headless Screws for Fixation of Displaced Radial Head Fractures: A Randomized Controlled Trial

BackgroundFixation of displaced radial head fractures using miniplates is technically challenging and has some drawbacks like hardware prominence and limitation of forearm rotation. Fixation by headless compression screws has emerged as a less invasive alternative to miniplates. This study compares the radiological and functional outcomes of both methods of fixation. MethodsThis single-center, prospective, randomized controlled trial was conducted at an academic level 1 trauma center. Sixty patients with displaced isolated radial head fractures were randomized to treatment using either headless compression screws or miniplates in 2 parallel groups. At the final follow-up of 18 months, patients were evaluated radiologically for union and clinically using the Mayo Elbow Performance Score (MEPS), elbow range of motion, grip strength, the visual analogue scale (VAS) for pain, and the Disabilities of the Shoulder, Arm, and Hand (DASH) score. ResultsUnion was achieved after 8±1.7 weeks in the screw group and after 8.5±2.7 weeks in the plate group. The MEPS was significantly better in the screw group (87.7±10.7) than in the plate group (80.5±13.9). However, this difference is below the minimum clinically important difference (MCID) for the MEPS and as such may not be clinically meaningful. No significant differences were observed between both groups regarding flexion, extension ranges, VAS, grip strength, or the DASH score. However, supination and pronation were significantly better in the screw group. The rate of complications was higher in the plate group (26.7%) than in the screw group (3.3%). ConclusionBoth techniques yielded comparable outcomes with better forearm rotation, a lower complication rate, and a lower hardware removal rate in the screw group.

TO STUDY THE FUNCTIONAL AND RADIOLOGICAL OUTCOMES OF ANKLE ARTHRODESIS WITH CORTICOCANCELLOUS SCREW FIXATION VS INTRAMEDULLARY NAILING

Objective: We aimed to evaluate the functional and radiological outcomes of ankle arthrodesis using corticocancellous screw fixation vs intramedullary nailing. Methods: In our study, 22 cases underwent the procedure. This evaluation was performed based on preoperative radiologic data and at postoperative clinical visits at 2 months, 6 months, and 12 mo required postoperatively. Radiologic outcomes were measured by: (1) Rate of union, (2) Rate of adjacent joint arthritis, and (3) Alignment of the ankle joint. Functional outcomes were measured by using the AOFAS score (American Orthopedic Foot and Ankle Society score). The patients' Subjective assessments were done using the Cumberland Ankle Instability Tool (CAIT). Results: The angle between the tibia's long axis and a line parallel to the talus's long axis is determined in the AP projection. The mean angle was 89.6 degrees (85-100 degrees) in the intramedullary nailing group (IMN group) and 91.4 degrees in the corticocancellous screw group (CC screw). The angle between the tibia's long axis and a line that is perpendicular to the talus’s long axis. The mean angle was 40.5 degrees (30-45 degrees) in the IMN group and 41.6 degrees in the CC screw group. The mean AOFAS score (American Orthopedic Foot and Ankle Society score) was 83.25 in the IMN group and 80.5 in the other group. The mean Cumberland Ankle Instability Tool (CAIT) score was 28 in the IMN group and 27.5 in the other group. All the cases showed bony union except one case, the average time taken for the union was 18.5 w in the IMN group and 20.5 w in the CC screw group. Conclusion: According to our study, all of the patients with normal angles between the tibia's long axis and a line perpendicular to the talus's long axis were obtained in the AP projection, and the angle between the tibia's long axis and a line that is perpendicular to the talus’s long axis. These patients also showed better Cumberland Ankle Instability Tool (CAIT) and AOFAS (American Orthopedic Foot and Ankle Society) scores in both comparison groups.

Duplex Fluorinated and Atomic Layer Deposition-Derived ZrO2 Coatings Improve the Corrosion Resistance and Mechanical Properties of Mg-2Zn-0.46Y-0.5Nd (wt.%) Alloy Plates and Screws.

This study investigated the corrosion resistance and mechanical properties of Mg-2Zn-0.46Y-0.5Nd (wt.%) alloy plates and screws with fluorinated coatings and atomic layer deposition (ALD)-derived zirconia (ZrO2) coatings in vitro under physiological stress conditions. Synthetic polyurethane hemimandible replicas were split and fixed as the following three groups of magnesium alloy plates and screws: no additional surface coating treatment (Group A), with fluorinated coatings (Group B), and with duplex fluorinated and ALD-derived 100 nm ZrO2 coatings (Group C). A circulating stress of 1-10 N was applied to the distal bone segment, and a 4-week simulated body fluid immersion test was employed to study the remaining material volume and the mechanical properties of the different groups. Compared with Group A and Group B, the degradation rate of magnesium alloy plates and screws' head regions was significantly slowed down under the protection of duplex MgF2/ZrO2 coatings (p < 0.01). There was no significant difference in the degradation rate of the screw shaft region between groups (p = 0.077). In contrast to fluoride coatings, duplex MgF2/ZrO2 coatings maintained the mechanical strength of magnesium alloy plates and screws after a 14 day in vitro SBF immersion test. We conclude that duplex MgF2/ZrO2 coatings exhibited a certain protective effect on the Mg alloy plates and screws under physiological stress conditions.

The effect of anterior support screw (AS2) in unstable femoral trochanteric fractures: A multicenter randomized controlled trial

ObjectivesThis study was conducted to verify the effectiveness of Anterior Support Screw (AS2) for unstable femoral trochanteric fractures. DesignA multicenter, prospective, randomized controlled trial SettingThis study was conducted across 15 academic medical centers in Japan Patients/ParticipantsWe enrolled 240 cases of femoral trochanteric fractures with posterior crushing and intramedullary displacement of proximal bone fragments across 15 institutions in Japan. InterventionAll patients were subjected to a reduction in which the anterior cortex was brought into contact. The patients were randomly assigned to the anterior support screw group (AS2 group) and the non-screw group (control group). Main Outcome MeasurementsTwo computed-tomography (CT) scans were taken immediately after surgery and early postoperative period (day 14–21) to investigate the reduction loss rate of the anterior cortex and sliding distances in the early postoperative period. ResultsThe reduction loss rate was 4.5 % in the AS2 group and 16.8 % in the control group, indicating a significantly lower reduction loss rate in the AS2 group (p = 0.003). The average sliding distance was 1.8 mm in the AS2 group and 2.8 mm in the control group, indicating a significantly shorter sliding distance in the AS2 group (p < 0.0001). ConclusionAdding a screw in front of the intramedullary nail significantly reduces reduction loss, and maintains anterior bony contact. This study also showed that these screws suppress the sliding distance during the postoperative period. Level of EvidenceTherapeutic Level I.