Comparison of the use of biocompatible materials and titanium in the treatment of midshaft clavicle fractures with a patient-specific plate: a finite element analysis study.

BACKGROUND: Clavicular midshaft fractures treated with titanium plates may encounter complications like implant failure. We assess if alternative biocompatible materials suchs as PLA, PLA/HA, PEEK offer comparable stability. Our study evaluates the biomechanical performance of these materials in surgical management of midshaft clavicle fractures. METHODS: We simulated a personalized fixation implant with four different materials and conducted finite element analysis in ANSYS to assess maximum von Mises stress (MvMs). RESULTS: The MvMs occurring on the plates, screws, clavicle, and fracture site were recorded. MvMs on titanium material at the 6th hole level (764.79 MPa) and the 6th screw level (503.38 MPa), with the highest stresses observed at 48.52 MPa on the lateral clavicle at the 1st hole level and 182.27 MPa on the medial clavicle at the 6th hole level. In PLA material analyses, the highest MvMs were observed at the 3rd hole level (340.6 MPa) and the 3rd screw level (157.83 MPa), with peak stresses at 379.63 MPa on the lateral clavicle fracture line and 505.44 MPa on the medial clavicle fracture line. In PLA/HA material analyses, the highest MvMs were at the 3rd hole (295.99 MPa) and 3rd screw (128.27 MPa), with peak stresses at 220.33 MPa on the lateral clavicle and 229.63 MPa on the medial clavicle fracture line. In PEEK material analyses, the highest MvMs were at the 3rd hole (234.74 MPa) and 6th screw (114.48 MPa), with peak stresses at 184.36 MPa on the lateral clavicle and 180.1 MPa on the medial clavicle. CONCLUSION: Our findings indicate that titanium material shows significantly higher stresses on plates and screws compared to those on the clavicle, suggesting a risk of implant failure. PLA and PLA/HA were inadequate for fixation. Although stress on the plate with PEEK material is higher than on the clavicle, it remains lower than titanium, indicating potential stability at fracture site. Further research is needed to confirm these findings.

Does vanillic acid affect fracture healing? An experimental study in a rat model of femur fracture.

BACKGROUND AND OBJECTIVES: We aimed to determine the effects of vanillic acid (VA) on fracture healing radiologically, histologically, immunohistochemically, and biomechanically using a rat femur open fracture injury model. METHODS: 32 male Wistar-Albino rats were used and divided into two groups: the study group (VA) and the control group. From the time they were operated on until they were sacrificed, the rats in the study group were given 100 mg/kg/day VA by oral gavage. After sacrification, the femurs were analyzed. RESULTS: It was observed that the Huo histological scoring was significantly higher in the VA group (p = 0.001), and the ratio of the amount of callus tissue compared to intact bone tissue was significantly higher. While no significant difference was observed in immunohistochemical H-scores in ColI antibody staining (p = 1.000), a borderline significant difference in favor of VA was observed in ColIII antibody staining (p = 0.078). In biomechanical analysis, failure load (N), total energy (J), maximum stress (MPa), and stiffness (N/mm) measurements were significantly higher in the VA group (p = 0.040, p = 0.021, p = 0.015, and p = 0.035, respectively). CONCLUSION: It has been observed that VA, with its antioxidative properties, increases fracture healing in rats, in which an open fracture model was created. We are hopeful that such an antioxidant, which is common in nature, will increase fracture healing. Since this study is the first to examine the effect of VA on fracture healing, further studies are needed.

Does the ulnohumeral angle have a role in the aetiopathogenesis of lateral epicondylitis?

The pathophysiology of lateral epicondylitis (LE) remains not fully elucidated, as it involves a complex interaction of anatomical structures. The primary objective of the research is to identify a potential relationship between LE and the ulnohumeral angle (UHA), which demonstrates the coronal alignment of the elbow. Patients diagnosed with LE between September 1st, 2020, and September 1st, 2023, were retrospectively examined. Demographic information and UHA measurements of patients meeting the inclusion criteria and a control group with similar criteria were collected. Measurements were independently conducted by 2 orthopedists at a 2-week interval and compared. Among 413 patients meeting the inclusion criteria and the control group comprising 420 patients, there were no significant differences in age, gender, and side (P = .447, P = .288, P = .159, respectively). The mean UHA for the LE group was 13.49 ±â€…4.24, while for the control group, it was 12.82 ±â€…9.19, showing a significant difference (P = .026). The inter-observer and intraobserver reliability of the angle measurements were both above 0.80. We hypothesize that the increase in UHA in patients with LE reflects an adaptive change secondary to compressive forces acting on the lateral aspect of the elbow. This study is the first to describe the relationship between LE and UHA based on anatomical-biomechanical foundations, suggesting a cause-and-effect relationship. Further studies are warranted to delve deeper into this relationship.

Single-plate versus double-plate comparison in the surgical treatment of comminuted clavicle fractures: Is the secondary plate reliable?

The objective of this study is to retrospectively assess the use of single-plate (SP) and double-plate (DP) fixation in the open reduction and internal fixation of comminuted clavicle fractures, focusing on fracture union and complications. We retrospectively evaluated comminuted diaphyseal clavicle fractures (Arbeitsgemeinschaft für Osteosynthesefragen type 15.B1-3) treated with open reduction and internal fixation and having a minimum 1-year follow-up. Two patient cohorts were identified: DP (utilizing a superiorly located clavicle-specific plate and an anteriorly located tubular plate) and SP (utilizing a superiorly located clavicle-specific plate). These groups were compared in terms of union time, peri-incisional numbness, implant irritation, return to work time, union rates, re-operation rates, Disabilities of Arm, Shoulder and Hand (DASH), and American Shoulder and Elbow Surgeons (ASES) scores. The study included 27 SP and 23 DP patients meeting the inclusion criteria. There was no significant difference between the 2 cohorts in terms of union time, peri-incisional numbness, implant irritation, return to work time, union rates, re-operation rates, DASH, and ASES scores at the end of the first year (P = .889, P = 1.00, P = .122, P = 1.00, P = 1.00, P = .493, P = .736, P = .762, P = .937 respectively). However, it was observed that the DP group showed a significantly earlier return to work time and better DASH scores at 3rd and 6th months, whereas the SP group exhibited significantly better ASES scores at 3rd and 6th months (P = .034, P = .016, P = .032, P = .036, P = .021, respectively). No significant difference was observed in terms of union and complications in acute clavicle fractures treated with SP and DP fixation. The DP group demonstrated an earlier return to work and superior early functional scores compared to the SP group. Our findings suggest that a secondary plate can be reliably used, particularly in situations where clavicle fracture fixation is insufficient or in cases of comminuted clavicle fractures.

Do lateral ankle ligaments contribute to syndesmotic stability: a finite element analysis study.

Whether the lateral ankle ligaments contribute to syndesmotic stability is still controversial and has been the subject of frequent research recently. In our study, we tried to elucidate this situation using the finite element analysis method. Intact model and thirteen different injury models were created to simulate injuries of the lateral ankle ligaments (ATFL, CFL, PTFL), injuries of the syndesmotic ligaments (AITFL, IOL, PITFL) and their combined injuries. The models were compared in terms of LFT, PFT and EFR. It was observed that 0.537 mm LFT, 0.626 mm PFT and 1.25° EFR occurred in the intact model (M#1), 0.539 mm LFT, 0.761 mm PFT and 2.31° EFR occurred in the isolated ATFL injury (M#2), 0.547 mm LFT, 0.791 mm PFT and 2.50° EFR occurred in the isolated AITFL injury (M#8). The LFT, PFT and EFR amounts were higher in the both M#2 and M#8 compared to the M#1. LFT, PFT and EFR amounts in M#2 and M#8 were found to be extremely close. In terms of LFT and PFT, when we compare models with (LFT: 0.650 mm, PFT: 1.104) and without (LFT: 0.457 mm, PFT: 1.150) IOL injury, it is seen that the amount of LFT increases and the amount of PFT decreases with IOL injury. We also observed that injuries to the CFL, PTFL and PITFL did not cause significant changes in fibular translations and PFT and EFR values show an almost linear correlation. Our results suggest that ATFL injury plays a crucial role in syndesmotic stability.

The effect of caffeic acid on tendon healing in rats with an Achilles tendon injury model.

OBJECTIVES: This study aims to examine the effect of caffeic acid on tendon healing histopathologically and biomechanically in rats with an Achilles tendon injury model. MATERIALS AND METHODS: Twenty male Wistar-albino rats were used in this study. The rats were divided into two groups as the experimental group and control group. All rats underwent a bilateral achillotomy injury model and then surgical repair. Postoperatively, for four weeks, the experimental group was given intraperitoneal caffeic acid (100 mg/kg/day suspended in saline), while the control group was given only intraperitoneal saline. At the end of four weeks, after sacrificing each rat, right Achilles tendons were subjected to biomechanical analysis and the Achilles tendons were subjected to histopathological analysis. Bonar and Movin scores were used for histopathological analysis. In biomechanical analysis, tensile test was applied to Achilles tendons until rupture. For each tendon, failure load, displacement, cross-sectional area, maximum energy, total energy, length, stiffness, ultimate stress and strain parameters were recorded. RESULTS: According to Bonar and Movin scoring, the experimental group had lower scoring values than the control group (p=0.002 and p=0.002, respectively). Bonar scoring parameters were analyzed separately. Vascularity, collagen, and ground substance scores were lower in the experimental group compared to the control group (p=0.001, p=0.003, and p=0.047, respectively). No significant difference was found for tenocyte (p=0.064). In biomechanical analysis, failure load, displacement, ultimate stress, strain, and stiffness values were found to be higher in the experimental group compared to the control group (p=0.049, p=0.005, p=0.028, p=0.021, and p=0.049, respectively). CONCLUSION: The caffeic acid contributed positively to tendon healing histopathologically and biomechanically in rats with an Achilles tendon injury model.

Biomechanical Analysis of Tibiofibular Syndesmosis Injury Fixation Methods: A Finite Element Analysis.

The optimal treatment strategy after syndesmotic injuries is still controversial. In our study, we aimed to evaluate ideal fixation method in syndesmotic injury by using finite element analysis method. A 3D SolidWorks model file was created by taking computed tomography (CT) images of the area from the right foot base to the knee joint level of a healthy adult male. The intact model, injury model, and 8 different fixation models were created that 3.5 mm screw and suture-button were used in. The models were compared in terms of lateral fibular translation, posterior fibular translation and external rotation of fibula compared to tibia and stress values occurred on screws and suture-buttons. In the hybrid-1 model, lateral fibular translation and external fibular rotation values were obtained as close to the intact model. Von Mises stresses occurred in the screw (435.7 MPa) and suture-button (424.7 MPa) that used in hybrid-1 model was more than single screw at 4 cm model (316.8 MPa) and single suture-button at 2 cm model (160.7 MPa). In the Hybrid-1 model, the screw compensates for posterior fibular translation and external fibular rotation, while the suture-button compensates for lateral fibular translation. Also, the effect of the distal suture-button preventing diastasis in case of proximal screw failure, it was concluded that the hybrid-1 model can be used as a good treatment alternative in the surgical treatment of distal tibiofibular syndesmotic injuries.

A new complication of femur head core decompression surgery: compartment syndrome.

The basic surgical treatment for avascular necrosis of the femur head is core decompression. In this report we discuss a case where the patient developed compartment syndrome after core decompression surgery with history of anticoagulant use. A 49-year-old man, who was using Coumadin 5 mg once daily due to aortic valve replacement and atrial fibrillation, had undergone core decompression surgery done due to stage 2 femur head avascular necrosis (AVN). He later developed isolated anterior thigh compartment syndrome for which fasciotomy was performed. Every surgical intervention to the extremities of patients with anticoagulant treatment should be considered high risk for compartment syndrome, even if appropriate precautions are taken. It is necessary to clinically observe for a sufficient duration to be able to identify symptoms.