Evaluation of Efficacy of Herbert Bone Screw and Lag Screw in Management of Oblique Mandibular Fractures: A Prospective Randomized Comparative Study.

Purpose: To assess the efficacy of Herbert cannulated bone screw versus Lag screw in fixation of oblique mandibular fractures. Materials and Method: Study composed of two groups of 20 patients each and descriptive statistics were performed with p value set at 0.05 with confidence interval of 95%. Group A was treated by Titanium Lag screws; while, Group B was treated by Titanium Herbert Cannulated Bone Screws for the management of oblique mandibular fractures. Postoperatively, all the patients were evaluated clinically and radiographically by recording the incidence of complications (if any) which included trismus, neurosensory deficit, swelling, infection. Parameters such as occlusal discrepancy, rigid fixation (interfragmentary gap) and duration of surgery were also recorded for all the patients. Results: All the patients were followed for a period of three months. Difference in mouth opening was found to be statistically significant during 1st month follow-up (p-Value-0.002). Postoperatively, the mean interfragmentary gap in Group A was significantly more than Group B (p-Value-0.000). Other parameters like neurosensory deficits, occlusal discrepancies, chewing efficiency, stability of fractured fragments and post-operative complications in terms of swelling, hardware exposure, radiolucency surrounding screw and wound dehiscence did not show any statistically significant difference. Conclusion: The obtained results showed that both lag screws and Herbert cannulated bone screws fulfill the treatment goals of adequate reduction, fixation and stabilization of oblique mandibular fractures. Herbert screws have shown to have better results in terms of interfragmentary gap reduction as compared to lag screws.

Lag Screw Exchange for Impinging Lateral Hardware Following Intramedullary Nailing of Intertrochanteric Hip Fractures - A Case Series Demonstrating Efficacy.

Background: This study aimed to demonstrate the feasibility of lag screw exchange for painful lateral soft tissue impingement in patients initially treated with cephalomedullary nailing (CMN) for an intertrochanteric hip fracture. Methods: Ten patients initially treated with CMN for unstable intertrochanteric fractures presenting with persistent pain and radiographic evidence of lag screw lateral migration were treated with exchange of original screw with shorter lag screw buried in the lateral cortex to prevent impingement. Patients were evaluated for resolution of pain and achievement of pre-fracture ambulatory status at 6 months post-operatively. Results: Average age was 71.5 years (range: 62-88). Average length of follow-up was 24.9 months. All patients were female, with an average Charlson Comorbidity Index of 1.0 (0-3) and average Body Mass Index of 22.2 (16.0-31.1). Five of ten patients (50.0%) were treated with a cortisone injection in the trochanteric bursa prior to screw exchange with temporary pain relief. Five (50.0%) patients presented with limited range of hip motion. Five (50.0%) had history of prior or current bisphosphonate use. Average lag screw prominence was noted to be 12.2mm (7.9-17.6mm) on radiographic evaluation. Screw exchange was performed at an average of 18.6 months (5.4-44.9 months) following the index procedure. Average operating time of the screw exchange procedure was 45.3 minutes (34-69 minutes) and blood loss was <50mL in all cases. Replacement lag screws were an average of 16.0mm (10-25mm) shorter than the initial screw. All patients achieved complete or significant resolution of lateral thigh pain, and nine (90%) returned to pre-fracture ambulatory status by eight weeks after screw exchange. All patients remained pain free at six months after screw exchange. Conclusion: Lag screw exchange is a efficacious method to address the mechanical irritation of laterally protruding lag screws following IT hip fracture, while also prophylaxing against subsequent femoral neck fractures. Level of Evidence: IV.

Forces required to dynamize sliding screws in gamma nail and selfdynamizable internal fixator.

BACKGROUND: Single limb support phase of the gait-cycle in patients who are treated for a pertrochanteric fracture is characterized by transversal loads acting on the lag screw, tending to block its dynamization. If the simultaneous axial force overcomes transversal loads of the sliding screw, the dynamization can still occur. METHODS: Biomechanical investigation was performed for three types of dynamic implants: Gamma Nail, and two types of Selfdynamizable Internal Fixators (SIF) - SIF-7 (containing two 7 mm non-cannulated sliding screws), and SIF-10 (containing one 10 mm cannulated sliding screw). Contact surface between the stem and the sliding screws is larger in SIF implants than in Gamma Nail, as the stem of Gamma Nail is hollow. A special testing device was designed for this study to provide simultaneous application of a controlled sliding screws bending moment and a controlled transversal load on sliding screws (Qt) without using of weights. Using each of the implants, axial forces required to initiate sliding screws dynamization (Qa) were applied and measured using a tensile testing machine, for several values of sliding screws bending moment. Standard least-squares method was used to present the results through the linear regression model. RESULTS: Positive correlation between Qt and Qa was confirmed (p < 0.05). While performing higher bending moments in all the tested implants, Qa was higher than it could be provided by the body weight. It was the highest in Gamma Nail, and the lowest in SIF-10. CONCLUSIONS: A larger contact surface between a sliding screw and stem results in lower forces required to initiate dynamization of a sliding screw. Patients treated for a pertrochanteric fracture by a sliding screw internal fixation who have longer femoral neck or higher body weight could have different programme of early postoperative rehabilitation than lighter patients or patients with shorter femoral neck.

Effect of lag screw on stability of first metatarsophalangeal joint arthrodesis with medial plate.

Background: First metatarsophalangeal joint (MTP-1) arthrodesis is a commonly performed procedure in the treatment of disorders of the great toe. Since the incidence of revision after MTP-1 joint arthrodesis is not insignificant, a medial approach with a medially positioned locking plate has been proposed as a new technique. The aim of the study was to investigate the effect of the application of a lag screw on the stability and strength of first metatarsophalangeal joint arthrodesis with medial plate. Methods: The bending tests in a testing machine were performed for models of the first metatarsal bone and the proximal phalanx printed on a 3D printer from polylactide material. The bones were joined using the locking titanium plate and six locking screws. The specimens were divided into three groups of seven each: medial plate and no lag screw, medial plate with a lag screw, dorsal plate with a lag screw. The tests were carried out quasi-static until the samples failure. Results: The addition of the lag screw to the medial plate significantly increased flexural stiffness (41.45 N/mm vs 23.84 N/mm, p = 0.002), which was lower than that of the dorsal plate with a lag screw (81.29 N/mm, p < 0.001). The similar maximum force greater than 700 N (p > 0.50) and the relative bone displacements lower than 0.5 mm for a force of 50 N were obtained for all fixation techniques. Conclusions: The lag screw significantly increased the shear stiffness in particular and reduced relative transverse displacements to the level that should not delay the healing process for the full load of the MTP-1 joint arthrodesis with the medial plate. It is recommended to use the locking screws with a larger cross-sectional area of the head to minimize rotation of the medial plate relative to the metatarsal bone.

Application of a combined cancellous lag screw enhances the stability of locking plate fixation of osteoporotic lateral tibial plateau fracture by providing interfragmentary compression force.

BACKGROUND: Insufficient interfragmentary compression force (IFCF) frequently leads to unstable fixation of osteoporotic lateral tibial plateau fractures (OLTPFs). A combined cancellous lag screw (CCLS) enhances IFCF; however, its effect on OLTPF fixation stability remains unclear. Therefore, we investigated the effect of CCLS on OLTPF stability using locking plate fixation (LPF). MATERIALS AND METHODS: Twelve synthetic osteoporotic tibial bones were used to simulate OLTPFs, which were fixed using LPF, LPF-AO cancellous lag screws (LPF-AOCLS), and LPF-CCLS. Subsequently, 10,000 cyclic loadings from 30 to 400 N were performed. The initial axial stiffness (IAS), maximal axial micromotion of the lateral fragment (MAM-LF) measured every 1000 cycles, and failure load after 10,000 cycles were tested. The same three fixations for OLTPF were simulated using finite element analysis (FEA). IFCFs of 0, 225, and 300 N were applied to the LPF, LPF-AOCLS, and LPF-CCLS, respectively, with a 1000-N axial compressive force. The MAM-LF, peak von Mises stress (VMS), peak equivalent elastic strain of the lateral fragment (EES-LF), and nodes of EES-LF > 2% (considered bone destruction) were calculated. RESULTS: Biomechanical tests revealed the LPF-AOCLS and LPF-CCLS groups to be superior to the LPF group in terms of the IAS, MAM-LF, and failure load (all p < 0.05). FEA revealed that the MAM-LF, peak VMS, peak EES-LF, and nodes with EES-LF > 2% in the LPF were higher than those in the LPF-AOCLS and LPF-CCLS. CONCLUSION: IFCF was shown to enhance the stability of OLTPFs using LPF. Considering overscrewing, CCLS is preferably recommended, although there were no significant differences between CCLS and AOCLS.

Is just one screw really enough? Single- versus double-screw in the medial malleolus in supination-external rotation ankle fractures: A comparative biomechanical study using partially threaded cancellous screws.

OBJECTIVE: The aim of this study is to investigate stiffness and the maximum load to failure values of single- and double-screw fixation of oblique medial malleolus fractures using partially threaded cancellous screws. Our hypothesis is that single-screw fixation of medial malleolus fractures after SER injuries provides similar stiffness when compared with double-screw fixation. DESIGN: Biomechanical study. METHODS: Twelve composite polyurethane synthetic right distal tibiae were used in the experiment. Oblique fractures of the medial malleolus were created with a band saw using a custom-made osteotomy guide to standardize the cuts in all models. Bone models were randomly separated into two groups and fixed with one (n = 6) or two (n = 6) 4.0 mm partially threaded cancellous screws placed perpendicular to the fracture line. These were tested by applying an offset axial tension at 10 mm/minute up to maximum load displacement, defined as subsidence of the medial malleolus fragment. Maximum load to failure was determined for the groups at the point where the curve ceased to be linear and suffered an inflection. Force versus displacement curves were obtained and recorded. The student's t-test for independent samples was used to compare stiffness (N / mm) and maximum load (N) between experimental groups, with a p value of < 0.05. RESULTS: There were no significant differences in stiffness (p = 0.290) and maximum load (p = 0.191) among the two fixation constructs. Mean stiffness was 62.26 (±SD 21.11) N/mm for double-screw fixation group and 48.24 (±SD 22.40) N/mm for single-screw fixation group. Mean maximum load was 387.83 (±SD 115.78) N for double-screw fixation group and 306.64 (±SD 81.97) N for single-screw fixation group. CONCLUSION: Fixation with one 4.0 mm partially threaded cancellous screw was not shown to be biomechanically inferior to fixation with two 4.0 mm partially threaded cancellous screws in an oblique fracture of the medial malleolus, supporting previous clinical studies that have shown that one screw is sufficient for fractures of the medial malleolus.

Computer-Assisted Intramedullary Nailing of Intertrochanteric Fractures Did Not Prevent Tip-Apex Distance Outliers.

Intertrochanteric femoral fractures are commonly treated with intramedullary nails (IMNs). A tip-apex distance (TAD) of more than 20-25 mm is associated with an increased risk of cut-out. The Stryker Adaptive Positioning System (ADAPT) is a computer-assisted navigation system designed to reduce TADs. We aim to assess if the ADAPT reduces the number of outliers with a TAD > 20 mm. All patients with intertrochanteric fractures treated with an IMN between 1 September 2020 and 12 March 2022 were included. Patients were included in three periods: a pre-ADAPT period (55 patients); an ADAPT period (50 patients), where it was compulsory to use the system; and a post-ADAPT period after the discontinuation of the system (59 patients). The TADs and lag screw protrusions beyond the lateral cortex were measured. The median TADs in the three periods were 17.0 mm (8-31 mm), 15.5 mm (9-30 mm), and 18.0 mm (11-32 mm), respectively. The absolute number of outliers with a TAD > 20 mm decreased from 15/55 patients in the pre-ADAPT period to 11/50 patients during the ADAPT period. This observation was not statistically significant, but this is likely due to the lack of power of the present study to show changes of this magnitude. However, our expectation that the ADAPT would diminish outliers markedly or close to zero outliers was not met, as we observed 11/50 = 22% outliers with a TAD > 20 mm when using computer-assisted surgery, i.e., ADAPT and Gamma3 for intertrochanteric fractures. Based on these findings, the use of the ADAPT was discontinued at our level 1 trauma center.

Augmentative lag screws as a treatment for aseptic hypertrophic nonunion after internal fracture fixation.

BACKGROUND: Hypertrophic nonunion after intramedullary (IM) nailing and plating is Uncommon and the treatment remained controversial. The aim of this study was to show the result of a simple augmentative lag screws technique for vital non-unions after internal fixation PATIENTS AND METHODS: We retrospectively reviewed the patients with nonunion after internal fixation between January 2016 to August 2022. Patients with unacceptable shortening or deformity were excluded as well as nonunion septic cases. All the patients were followed up for at least 6 months. RESULTS: Seven patients achieved bony union in a median time of 12 weeks (IRQ 12-16). There was a failure case with persistent non-union and brokerage of the screws. DISCUSSION: Various techniques have been described to treat non-union after intramedullary nailing or plating. The existing nail is frequently removed, and the non-union site is either re-reamed and re-nailed or fixed with a plate or external fixation devices or rechanged by a nail in the case of plates. In our study of non-union, augmentative lag screws were successfully applied to treat eight patients with aseptic nonunion, resulting in the healing of non-union in all cases except one. CONCLUSION: Augmentative lag screws represent a simple technique for the management of aseptic hypertrophic nonunion after internal fixation with a significantly shorter operating time.

Antegrade posterior column screw fixation for acetabular fractures: It's time to standardize the surgical technique.

Antegrade fixation of posterior column fractures of the acetabulum is challenging due to the narrow corridor and risk of screw misplacement. Although both antegrade and retrograde lag screws have been previously described for posterior column fracture fixation, the literature lacks a standardized technique for correct and safe screw placement, especially in an antegrade fashion. This technical note aims to optimize intraoperative images during posterior screw insertion using the antegrade technique, according to predetermined landmarks to save surgical time, decrease radiation exposition, and prevent surgical complications.

Biomechanics of sacroiliac joint fixation using lag screws: a cadaveric study.

BACKGROUND: Iliosacral screw placement is ubiquitous and now part of the surgeon's pelvic trauma armamentarium. More recent evidence supports sacroiliac arthrodesis for treating sacroiliac joint (SIJ) dysfunction in select patients. Regardless of the surgical indication, there are currently no studies examining lag screw compression biomechanics across the SIJ. The objective of this biomechanical investigation was to quantify iliosacral implant compressive loads and to examine the insertion torque and compressive load profile over time. METHODS: Eight human cadaveric pelvic specimens underwent SIJ fixation at S1 and S2 using 11.5 and 10.0 mm iFuse-TORQ Lag implants, respectively, and standard 7.3 mm trauma lag screws. Load decay analysis was performed, and insertion and removal torques were measured. RESULTS: For both implants at S1 and S2 levels, the load relaxed 50% in approximately 67 min. Compressive load decay was approximately 70% on average occurring approximately 15 h post-insertion. Average insertion torque for the 11.5 mm TORQ implant at S1 was significantly greater than the trauma lag screw. Similarly, at S2, insertion torque of the 10.0 mm TORQ implant was greater than the trauma lag screw. At S1, removal torque for the 11.5 mm TORQ implant was higher than the trauma lag screw; there was no significant difference in the removal torque at S2. CONCLUSIONS: In this study, we found that a novel posterior pelvic implant with a larger diameter, roughened surface, and dual pitch threads achieved improved insertion and removal torques compared to a standard screw. Load relaxation characteristics were similar between all implants.

The Effect of Bone Quality on Treatment of Intertrochanteric Fractures with Helical Blade Versus Lag Screw Fixation in Cephalomedulary Nails.

Introduction: The specific aim of this retrospective study was to determine whether bone quality has any effect on the complication rates or overall survivorship between helical blades and lag screws in cephalomedullary nails used for intertrochanteric hip fractures. Methods: The authors reviewed clinical charts and radiographic studies of patients between January 2012 and August 2019. We reviewed radiographic images (pre-, intra-, and post-operative) to evaluate fracture fixation type, fracture reduction grade, and post-operative complications. We collected dual energy x-ray absorptiometry scan results (T-score) and serum alkaline phosphatase (ALP) isoenzyme activity values to evaluate patient bone quality. Results: We included 303 cases (helical: 197, screw: 106) in the study. Complications were found in 31 (16%) helical blade cases and 23 (22%) lag screw cases. No statistically significant difference was detected when comparing complication rates with patient bone quality between the two groups. These two groups had similar one-year implant survivorship with respect to T-score, the low ALP level group, and normal ALP level group. The helical blade had higher implant survivorship compared to lag screw in five-year survival rate with respect to osteoporotic group, high ALP level group, and normal ALP level group (osteoporotic: 77% vs 69%, high ALP: 73% vs 67%, normal ALP: 70% vs 64%). Conclusions: Similar complication rates were observed between helical blade and lag screw constructs in cephalomedullary femoral nails when accounting for patient bone quality. However, the helical blade design had a higher five-year survival rate.

A case of total hip arthroplasty for nonunion after femoral trochanteric fracture surgery with complete breakage of only the compression screw of the InterTAN nail.

Intramedullary nails are an effective treatment for common femoral trochanteric fractures. However, one of their complications is implant breakage due to poor reduction and nonunion after surgery. We herein report a case of a 54-year-old man who underwent total hip arthroplasty for nonunion after internal fixation of a femoral trochanteric fracture. The femoral trochanteric fracture was treated by internal fixation using the Trigen InterTAN nail. The patient developed symptoms of hip pain 6 months after internal fixation. Nine months after internal fixation, hip radiographs and computed tomography scans showed breakage of only the compression screw. During total hip arthroplasty, we were unable to remove the lag screw and compression screw before the femoral head dislocation because no gap was present between the two screws. Thus, we removed these screws with the femoral head after dislocation of the femoral head. The removed nail was partially damaged at the lag screw hole. This change was retrospectively observed on the preoperative computed tomography scan. Three months after total hip arthroplasty, the patient was able to walk unaided and the hip pain had resolved. If only the compression screw is completely broken after internal fixation with the Trigen InterTAN nail, both the lag screw and compression screw will be difficult to remove with preservation of the femoral head. We effectively managed such a case by not only revision internal fixation but also total hip arthroplasty.

No effect of hydroxyapatite-coated sliding hip screw threads on screw migration in the femoral head/neck of pertrochanteric fractures: a randomized controlled trial using radiostereometric analysis.

INTRODUCTION: Cut-out is the most frequently reported mechanical failure of internal fixation of pertrochanteric fractures. The purpose of this study was to examine if hydroxyapatite-coated screw thread on a sliding hip screw (SHS) could reduce screw migration within the femoral head in patients with stable pertrochanteric fractures. MATERIALS AND METHODS: In a double-blinded randomized controlled study, 37 patients at mean age 78 (range 56-96), with pertrochanteric fracture (Evans I, II, IV) received surgery with a SHS with a hydroxyapatite-coated or a non-coated lag screw thread. Radiostereometry and standard radiographs were obtained 1 day, 6 weeks, 3- and 6 months post-operatively to evaluate screw and fracture migration and fracture reposition. The two groups were combined to describe fracture migration. RESULTS: There was similar and small screw migration in the femoral head between the two groups at 6 weeks, 3- and 6 months (p > 0.12). Fracture migration occurred predominantly in the first 6 weeks, where fracture impaction was 5.95 mm (CI 95% 2.87 to 9.04) and anterior rotation of the femoral head was -2.94° (CI 95% - 5.22 to - 0.66). Migration of the fracture (total translation) correlated to the post-operative fracture reposition (p = 0.002), but not significantly to screw migration (p = 0.09). Neither screw total translation (rho 0.06, p = 0.79) nor fracture total translation (rho 0.04, p = 0.77) correlated with bone mineral density. CONCLUSION: There was no clinical benefit of hydroxyapatite coating on lag screw migration in this patient cohort. Migration of the pertrochanteric fractures was higher with poor fracture reposition but fractures generally stabilized after 6 weeks follow-up. The study was registered at ClinicalTrials.gov (NCT05677061). LEVEL OF EVIDENCE II: Patient-blinded prospective randomized study. Trial registration number The study was registered at ClinicalTrials.gov (NCT05677061).

[Effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeâ ¡scapular pelvis fracture].

OBJECTIVE: To analyze the effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeⅡscapular pelvis fracture. METHODS: From January 2016 to June 2021, 26 patients with Ideberg typeⅡglenoid fractures were treated with trans-axillary lag screw combined with supporting plate, including 15 males and 11 females. The age ranged from 21 to 75 years, with an average of (43.12±6.56) years old. The Constant-Murley Shoulder joint Scale and University of California at Los Angeles (UCLA) score were used to evaluate the function and clinical efficacy of shoulder joint. RESULTS: All patients were followed up, and the duration ranged from 19 to 42 months, with an average of (30.6±10.5) months. One year after surgery, the Constant-Murley score increased from preoperative 34.9±2.5(ranged, from 28 to 47) to 87.2±6.8(ranged, from 70 to 95). The UCLA score improved from preoperative 17.9±1.7(9 to 25) to 33.1±2.3(29 to 35). Seventeen patients got an excellent result, with 7 good, and 2 fair. None of the patients had infection, screw, and plate loosening, fracture, and other complications after surgery. Two patients had different degrees of Chronic pain in the shoulder during the follow-up period. CONCLUSION: The treatment of Ideberg typeⅡscapular glenoid fractures through axillary approach with lag screws and supporting steel plates has the advantages of convenient exposure, direct visual restoration of the normal anatomical shape of the scapular glenoid, selection of suitable positions for screw and steel plate placement, achieving better treatment results, and fewer complications. It is an effective and reliable surgical method.

Proposal of a modified tip apex distance for prediction of lag screw cut-out in trochanteric hip fractures.

INTRODUCTION: Lag screw cut-out is a serious complication of dynamic hip screw fixation of trochanteric hip fractures. The lag screw position has been acknowledged as one of the important factors affecting the lag screw cut-out. We propose a modification of the Tip Apex Distance (TAD) and hypothesise that it could improve the reliability of predicting lag screws cut-out in these injuries. MATERIALS AND METHODS: A retrospective study was conducted for hip fracture entries in the period from Jan 2018 to July 2022. A hundred and nine patients were suitable for the final analysis. The modified TAD was measured in millimetres based on the sum of the traditional TAD in the lateral view and the net value of two distances in the AP view, the first distance is from the tip of the lag screw to the opposite point on the femoral head along the axis of the lag screw while the second distance is from that point to the femoral head apex. The first distance is a positive value, whereas the second distance is positive if the lag screw is superior and negative if inferior. A receiver operating characteristic curve was used to evaluate the reliability of the different parameters assessing the lag screw position within the femoral head. RESULTS: Reduction quality, fracture pattern as per the AO/OTA classification, TAD, Calcar Referenced TAD, Axis Blade Angle, Parker's ration in the AP view, Cleveland Zone 1, and modified TAD were statistically associated with lag screw cut-out. Among the tested parameters, the modified TAD had 90.1% sensitivity and 90.9% specificity for lag screw cut-out at a cut-off value of 25 mm with a P-value < 0.001. CONCLUSION: The modified TAD had the highest reliability in the prediction of lag screw cut-out. A value ≤ 25 mm could potentially protect against lag screw cut-out in trochanteric hip fractures.

Endovascular assisted removal of intrapelvic lag screw after intramedullary proximal femoral nail: A case report and literature review.

Background: Trochanteric fractures are very common hip injuries often fixed with intramedullary nailing as the recommended treatment. Medial lag screw migration of the intramedullary nail system is an uncommon complication. The objective of this case report is to highlight the importance of optimal reduction in hip fractures and the need for a multidisciplinary approach with vascular assistance in intrapelvic lag screw migration. Case report and results: We collected 24 cases of intrapelvic migration of the lag screw in the latest literature. Here, we report the case of a 68-year-old patient with medial pelvic migration of the lag screw after minor trauma and its removal using peroperative simultaneous angiography. After removal of the osteosynthesis material, a revision to a total hip arthroplasty was performed. Conclusion/discussion: This is the first case demonstrating an endovascular assisted removal simultaneous with revision surgery. We suggest that a multidisciplinary approach is warranted in which the orthopedic surgeon is assisted by a vascular surgeon. An endovascular assisted open removal of the lag screw with conversion to a hip arthroplasty is considered a safe treatment.

Which head element is more effective for cement augmentation of TFNA? Helical blade versus lag screw.

BACKGROUND: Early fixation and rehabilitation is the gold standard treatment for intertrochanteric femur fractures. Cement augmentation through perforated head elements has been developed to avoid postoperative complications such as cut-out or cut-through. The purpose of this study was to compare two head elements in terms of cement distribution using computed tomography (CT) and to examine their initial fixation and clinical outcomes. METHODS: Elderly patients who had intertrochanteric fractures were treated with a trochanteric fixation nail advanced (TFNA) helical blade (Blade group) or a TFNA lag screw (Screw group). In both groups, 4.2 mL of cement was injected under an image intensifier (1.8 mL of cement was directed cranially and 0.8 mL each caudally, anteriorly, and posteriorly). Patient demographics and clinical outcome were investigated post-operatively. Cement distribution from the center of the head element was evaluated with CT. Maximum penetration depth (MPD) were measured in the coronal and sagittal planes. On each axial plane, the cross-sectional areas in the cranial, caudal, anterior and posterior directions were calculated. The sum of cross-sectional areas (successive 36 slices) was defined as the volume of the head element. RESULTS: The Blade group included 14 patients, and the Screw group included 15 patients. In the Blade group, MPD in the anterior and caudal direction was significantly greater than that in the posterior direction (p < 0.01). In the Screw group, volume in the cranial and posterior direction was significantly greater than that in the Blade group (p = 0.03). Subsequently, the total volume in the Screw group was significantly larger than that in the Blade group (p < 0.01). No significant correlation was detected between bone mineral density, T score, young adult mean, and total cement volume. Change in radiographic parameters and clinical outcome such as Parker score and visual analog scale were similar in both groups. No patients suffered from cut-out / cut through or non-union. CONCLUSIONS: The position of cement distribution through the lag screw is different from that through the helical blade, and the total volume of the head element is significantly larger in the lag screw. Both groups had similarly effective results in terms of mechanical stability after surgery, postoperative pain and early phase of rehabilitation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN45341843, 24/12/2022, Retrospectively registered.

Intramedullary Femur Nailing in Intertrochanteric Fractures: Postoperatively Do Helical Blades Migrate More Than Lag Screws? A Randomized Controlled Trial.

Objectives: This was a prospective, randomized controlled trial to test functional outcomes between a single lag screw and helical blade nails in the treatment of intertrochanteric fractures. Methods: 72 patients with intertrochanteric fractures between March 2019 to November 2020 were randomized into two groups and treated with a lag screw or a helical blade nail. Intraoperative parameters such as operative time, blood loss, and radiation exposure were calculated. Postoperatively, tip apex distance, neck length, neck-shaft angle, lateral impingement of implant, union rate, and the functional outcomes were measured at the end of 6 month follow-up period. Results: There was a significant decrease in tip apex distance (p = 0.03) and neck length(p-0.04) with significant lateral impingement of the implant (p = 0.04) in the helical blade group compared to the lag screw group. The functional outcome calculated using the modified Harris Hip score & Parker and Palmer mobility score, at the end of 6 months, had no significant difference between the two groups. Conclusion: Both lag screw and helical blade devices can be used to successfully treat these fractures, although there is greater medial migration in the helical blade as compared to the lag screw.

Minimally invasive percutaneous new designed transpedicular lag-screw fixation for the management of Hangman fracture using O-arm-based navigation: a clinical study.

BACKGROUND: To investigate the outcomes and safety of using minimally invasive percutaneous new transpedicular lag-screw fixation with intraoperative, full rotation, three-dimensional image (O-arm)-based navigation for the management of Hangman fracture. METHODS: Twenty-two patients with Hangman fracture were treated with minimally invasive percutaneous new transpedicular lag-screws using intraoperative, full rotation, and three-dimensional image (O-arm)-based navigation. The preoperative and postoperative conditions of the patients were evaluated according to the ASIA (American Spinal Injury Association) scale. The patient's VAS (visual analog scale) scores before and after surgery, operation time, cervical vertebral activity, intervertebral angle and bone healing were recorded and collected, and repeated measures analysis of variance was used for statistical analysis. RESULTS: All patients were satisfactorily repositioned after surgery, and the VAS scores for neck pain were significantly lower than those before surgery on the first day and at 1 month, 3 months and the last follow-up (P < 0.001). According to the ASIA scale, four patients recovered from preoperative grade D to postoperative grade E. Bony fusion was achieved for all cases, and the range of neck rotation was restored to normal at the last follow-up. The post-surgery angular displacement (AD) demonstrated the stability of C2-3 after our new screw fixation for the treatment of Hangman fracture. CONCLUSIONS: Minimally invasive percutaneous new transpedicular lag-screw fixation using intraoperative, full rotation, three-dimensional image (O-arm)-based navigation achieved satisfactory clinical results with the advantages of immediate stability, safety and effectivity. We suggest that it is a reliable and advanced technique for the management of Hangman fracture.

Comparing the torsional resistance of different fixation techniques for spiral metacarpal fractures.

This study aimed to compare the torsional resistance of three fixation techniques for spiral metacarpal fractures: screw-only fixation, screw plus neutralization plate fixation, and a locking plate construct. A spiral fracture was created on 18 cadaveric metacarpal bones by applying an axial and torsional loading force using an Instron 3343 mechanical tester. The failure strength was defined as the native torque strength. The fractures were divided into three groups and fixed using each of the three techniques. The repaired bones were loaded to failure to determine the post-repair strength. The neutralization plate group conferred a post-repair torque (278.6 Nmm) that was similar to the native torque (292 Nmm) with a diminution of only 4.5% and appeared to provide the best resistance to torsion.