Mean S1 inlet and outlet view angles are not safe for all individuals according to three-dimensional tomographic measurements.

Although there are many studies evaluating optimal inlet and outlet angles required for the correct placement of S1 iliosacral screws, there is no study evaluating reliability and feasibility of these angles for all individuals on three-dimensional (3D) anatomical models. A total of 100 women and 100 men were selected randomly. A vertical line was created according to long axis of the tomography device on which patient was lying in supine position. The automatized best-fit planes were created on superior and inferior endplates, anterior cortex including notch region and posterior cortex of first sacral vertebrae using 3D imaging software to measure mean inlet and outlet angles. We observed no statistically significant difference between gender groups in terms of inlet and outlet angles. Mean inlet view is obtained for anterior cortex of S1 in 22.5 ± 9.5° and for posterior cortex in 46.5 ± 9.3°. Mean fluoroscopic view angle of S1 for superior outlet is 40.3 ± 7.6 and for inferior outlet is 46.9 ± 8.8. Mean anterior and posterior S1 inlet view angles do not accurately visualize anterior cortex of 74 (37%) and posterior cortex of 66 (33%) individuals. Mean superior and inferior S1 outlet view angles do not accurately visualize superior endplate of 74 (37%) and inferior endplate of 56 (28%) individuals. Due to individual alterations of spatial position of sacrum, mean inlet and outlet view angles of S1 are not sufficient to visualize the iliosacral screws under fluoroscopy in many individuals.

TT-TG distance decreases after open wedge distal femoral varization osteotomy in patients with genu valgum & patellar instability. A pilot 3D computed tomography simulation study.

BACKGROUND: Genu valgum is considered to be a risk factor for patellar instability. Correction of valgus alone or combined with a tibial tuberosity medialization has been described. However, changes occurring in the tibial tuberosity-trochlear groove (TT-TG) distance after a lateral distal femoral opening wedge osteotomy (LDF-OWO) are not known. PURPOSE: This study aimed to define changes in TT-TG distance with increasing amounts of valgus correction after LDF-OWO. METHODS: Three-Dimensional Computed Tomography (3D-CT) scans of six patients (two females and four males) aged between 19 and 35 years with genu valgum and patellar instability were analyzed. 3D models of femoral, tibial, and patellar bones were created with the advanced segment option of Mimics 21® software. An oblique lateral opening wedge osteotomy of the distal femur was simulated in 2-degree increments up to 12 degrees of varus opening. Change in TT-TG distance was measured in mm on 3D models of the knee. RESULTS: Compared to baseline without osteotomy, the TT-TG distance decreased significantly (p < 0.05) for all corrections from 2 to 12 degrees in 2° steps. The TT-TG distance decreased by an average of 1.7 mm for every 2 degrees of varus opening. CONCLUSION: Lateral opening wedge distal femoral osteotomy causes a decrease in TT-TG distance. The surgeon should be aware of the magnitude of this change (1.7 mm decrease for every 2° increment of valgus opening).

A clinical comparison of two different surgical techniques in the treatment of acute Achilles tendon ruptures: Limited-open approach vs. percutaneous approach.

BACKGROUND: Surgical treatment is the commonly preferred method for treating acute Achilles tendon ruptures (AATRs) due to advantages such as less re-rupture rates, better functional results, and an early return to physical activities. The main aim of our study is to compare two common minimally invasive surgical methods, the limited open and the percutaneous approaches, regarding clinical outcomes. METHODS: A total of 53 patients (19 females and 34 males) who were treated with limited open (Group 1: 30 patients) and percutaneous (Group 2: 23 patients) approaches for AATRs were retrospectively evaluated between March 2019 and May 2020 in a level 1 trauma center. The evaluation included complications (soft tissue and skin problems, re-rupture, and sural nerve injury rates), the operation time, the duration of return to daily activities, The Achilles Tendon Total Rupture Score (ATRS), and the American Ortho-pedic Foot and Ankle Society (AOFAS) scores of the patients at the first and 6th months of follow-up. Patients' activity levels were compared with the Tegner Activity Scale (TAS). RESULTS: The mean age of all patients in this cohort was 45.1±14.1. The mean postoperative follow-up period for group 1 was 36.9±8.81 weeks, whereas, for group 2, it was 35.4±8.73 weeks (P=0.24). The mean age (P=0.47), gender distribution (P=0.41), and body mass index (P=0.29) were similar for both groups. The mean operation time (group 1: 47.1±5.4 vs. group 2: 44.4±6.1, P=0.06) and the duration of return to daily activities (group 1: 49.2±7.4 vs. group 2: 48.5±9.7, P=0.38) were also similar. There was no statistical difference between groups regarding functional results at first (ATRS: group 1: 79.9±3.2 vs. group 2: 79.5±3.9, [P=0.35], and AOFAS: group 1: 80.9±3.1 vs. group 2: 82.1±3.2, [P=0.10]) and 6th months (ATRS: group 1: 85.0±3.8 vs. group 2: 83.7±4.4, [P=0.13], and AO-FAS: group 1: 86.6±3.6 vs. group 2: 86.7±4.2, [P=0.46]). There were no statistically significant differences between groups regarding preoperative and last follow-up TAS scores (P= 0.94 and P=0.46, respectively). We observed no postoperative complications in group 1. There were three complications (13.1%) in group 2. One patient (4.4%) had a re-rupture, and two patients (8.7%) had sural nerve injuries. CONCLUSION: Although both groups had similar functional results, the limited open approach yielded better clinical outcomes according to the complication results than the percutaneous approach.

Determination of the Optimal Syndesmosis Fixation Angle Using the Mortise View of the Ankle Joint.

BACKGROUND: Syndesmosis is an important soft-tissue component supporting ankle stability. It is commonly injured along with ankle fractures. Accurate reduction and fixation of syndesmosis is essential to obtain better functional results. Therefore, we aimed to find a practical method using the mortise view of the ankle to determine the optimal syndesmosis fixation angle intraoperatively. METHODS: We randomly selected 200 adults (100 women and 100 men) aged 18 to 60 years. Three-dimensional anatomical models of the tibia and fibula were created. We created a best-fit plane on the articular surface of the medial malleolus and a 90° vertical plane to the medial malleolus plane. We determined two splines on the cortical borders of the tibia and fibula distant from the most superior point of the ankle joint in horizontal view. We created two spheres that fit to the predefined splines. The optimal syndesmosis fixation angle was determined measuring the angle between the line connecting the center points of the spheres and the 90° vertical plane to the medial malleolus plane. RESULTS: We observed no statistically significant difference in optimal syndesmosis fixation angles between sex groups. The participant mean ± SD age was 47.1 ± 10.5 years. The optimal syndesmosis fixation angle in the mortise view was found to be 21° ± 4.3°. CONCLUSIONS: We determined the optimal syndesmosis fixation angle to be 21° ± 4.3° using the mortise view of the ankle. The surgeon could evaluate the whole articular surface of the ankle joint with the medial and lateral syndesmotic spaces in mortise view accurately, and at the same position syndesmosis fixation could be performed at a mean ± SD angle of 21° ± 4.3°.

Determination of the Gender-Related Differences on Native Femoral Anatomy Using Three-Dimensional Computerized Tomography Models in Caucasian Population.

Introduction Three-dimensional (3D) modelling, which has an increasing interest in the literature, could help surgeons to better understand the lesions by visualizing the real anatomical features compared to plain radiographs and two-dimensional (2D) tomography images. We aimed to evaluate the native femoral anatomical features of Turkish females and males using 3D computed tomography models. Methods We evaluated the right femoral anatomical features of 60 females and 60 males between 31 and 65 years of age creating 3D computerized tomography models. The gender-specific differences of femoral neck inclination and anteversion, femoral mechanical-anatomical axis, anatomical and mechanical lateral distal femoral, medial and lateral proximal femoral angles were measured on 3D femoral anatomical models. Results The mean age of our study groups was 50.6 ± 8.5. We determined a statistically significant difference between gender groups in terms of mean femoral neck anteversion angles (p = 0.009). We observed the retroversion of the femoral neck in 12 adults (10%). The mean values of femoral neck inclination, femoral mechanical - anatomical angle, anatomical and mechanical lateral distal femoral angles, medial and lateral proximal femoral angles did not differ any statistical significance between gender groups. Conclusion Although the anatomical angle measurements except femoral neck anteversion, did not differ significantly between gender groups of our study, there were differences between mean anatomical angles when compared to other studies in the literature, which investigate the different races or Caucasian population. Through 3D anatomical data, more compatible implants, prosthesis or biomaterials can be produced by determining gender and race-specific anatomical differences.

Is Proximal Tibia Sufficient for Accurate Measurement of Tibial Slope Angles on Three-dimensional Tomography-based Anatomical Models?

BACKGROUND: Tibial slope measurements performed using only the proximal part of tibia ignore the native tibial anatomical axis. Our first aim is to measure the native medial, lateral and total tibial slope angles of gender groups using the whole tibial anatomical axis on computerized tomography-based three-dimensional anatomical models. The second aim is to determine the correlation between proximal and whole tibial anatomical axis for measurement of medial, lateral, and total tibial slope angles. METHODS: We randomly selected 100 females and 100 males between 18-60 years of age. Three-dimensional anatomical models of right and left tibia were created. The gender-specific differences of medial, lateral, and total tibial slope angles according to proximal and whole tibial anatomical axis were measured. Correlation coefficients (r) of medial, lateral, and total tibial slope angles measured with proximal and whole tibial anatomical axis were calculated. RESULTS: The mean age was 47.1 years. A statistically significant difference was observed between female (7.1 ± 3) and male (8.2 ± 2.5) groups in terms of mean lateral tibial slope angles according to the whole tibial anatomical axis (p=0.008). A strong correlation between proximal and whole tibial anatomical axis for all tibial slope angle measurements was detected. CONCLUSION: The method we determined for 3D measurement of medial, lateral and total tibial slope angles using proximal tibial anatomical axis has a strong correlation with slope angles measured in accordance with the whole tibial anatomical axis. Our 3D tibial slope angle measurement method on the proximal tibia has high reliability and could be used in the daily practice.

Intramedullary implants coated with cubic boron nitride enhance bone fracture healing in a rat model.

BACKGROUND: Boron nitride is a biocompatible and an osteo-inductive material for orthopedic applications. The aim of this study was to evaluate the effects of two different allotrope boron nitride coated implants, cubic boron nitride and hexagonal boron nitride, on fracture healing. METHODS: In this experimental study, a total of 24 rats were divided into three groups. Group A was the control group with Kirschner wire without coating, while the wires were coated dominantly by cubic boron nitride in Group B and hexagonal boron nitride in Group C. Then a mid-third femoral fracture was created. The fracture healing was examined in terms of new bone formation with micro-CT analysis and histopathological examination, quantitative measurement of bone turnover metabolites and scintigraphic examination of osteoblastic activity on 28th day post fracture. RESULTS: Micro-CT measurement results revealed a statistically significant increase in bone volume/tissue volume ratio and bone surface values in group B compared to group A. Cortex diameter and osteoblast counts were statistically higher in group B compared to group A. Inflammatory response was increased in group C compared to groups A and B. Biochemical test results showed significantly increased alkaline phosphatase levels and decreased osteocalcin levels in group B compared to group A. The increase in serum phosphorus and decrease in serum calcium levels was statistically significant in group C compared to Group A. CONCLUSION: Both types of boron nitride coating had superior fracture healing features compared to control group. Therefore, c-BN coating can accelerate the fracture healing and could lead to shorten of union time.

Clinical and radiological outcomes of patients treated with the talon distalfix proximal femoral nail for intertrochanteric femur fractures.

BACKGROUND: The Talon™ DistalFix™ Proximal Femoral Nail (Talon-PFN) is a new proximal femoral intramedullary nail designed for the treatment of intertrochanteric femoral fractures. This study aimed to report the clinical and radiological outcomes of patients treated using a proximal femoral intramedullary nail with a novel design. METHODS: Patients with either stable or unstable (AO/OTA type 31-A1, 2, 3) intertrochanteric fractures who were treated with the Talon-PFN between October 2014 and January 2018 in our department participated in this retrospective study. Patients' demographics, clinical characteristics, and functional and radiographical outcomes were evaluated. RESULTS: A total of 110 patients (65 females, 45 males) with a mean age of 80.6 ± 9.1 years participated in this study. The mean follow-up time was 24 ± 13.4 months. The overall mortality rate during follow-up was 50.48%. The most common perioperative complications were a malposition of the femoral neck screw and talon cutout, both of which occurred in 17 patients (15.5%). The most common complications observed during follow-up were a lesser trochanter nonunion/malunion in 34 patients (30.9%), valgus malunion in 18 patients 16.4%), lateral screw migration in four patients (3.6%), and varus malunion in 15 patients (13.7%). A late screw cutout through the femoral head was seen in four patients (3.6%). At least one complication was detected in 53 patients (48.2%). However, revision surgery was performed in only six of these cases (5.5%). CONCLUSION: According to the results obtained in this study, the Talon-PFN, which has similar clinical and radiological outcomes compared to other proximal femoral intramedullary nail designs according to the reported studies, can be a suitable alternative in the treatment of intertrochanteric fractures.

Titanium Alloy Intramedullary Nails and Plates Affect Serum Metal Ion Levels within the Fracture Healing Period.

Titanium alloy implants are the most used materials for the fixation of lower extremity fractures. Although these implants were thought to be inert materials in vitro, several studies have shown increased serum and remote tissue metal ion levels due to wear of implants and friction of the bone-implant interface in vivo. The aim of this study was to investigate the alteration of serum metal ion levels that are released from intramedullary nails and plates used for the fixation of lower extremity fractures, within the fracture healing period. The study included 20 adult patients, who were treated with intramedullary nail or plate osteosynthesis due to closed lower extremity fractures. Alterations of serum titanium, aluminum, molybdenum, and vanadium levels were evaluated at 6, 12, 18, and 24 weeks postoperatively. A statistically significant increase was determined in serum titanium, aluminum, molybdenum, and vanadium ion levels in the intramedullary nail and plate groups at the end of the follow-up period. Pairwise comparisons of metal ion levels between implant groups revealed no significant difference during a 24-week follow-up period. Compared to the control group, statistically significant increased levels of serum titanium, aluminum, vanadium, and molybdenum ions were determined in the implant groups used for the fixation of lower extremity fractures at the end of 24 weeks. In the current literature, the potential toxic effects of prolonged exposure to low levels of these metal ions are still unknown. It can be predicted that long-term metal ion exposure could result in vivo pathological processes in the future.

Two-Stage Surgery for the Malleolar Fracture-Dislocation With Severe Soft Tissue Injuries Does Not Affect the Functional Results.

Soft tissue injuries associated with malleolar fracture-dislocations may increase postoperative rates of wound complication. Ankle-spanning frame plays a fundamental role in the local damage control orthopedics while gaining time for definitive surgery. The objective of this study was to evaluate the effect of a 2-stage surgery for the unstable malleolar fracture-dislocations with severe soft tissue injuries compared to a 1-stage surgery in terms of the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle and Olerud-Molander ankle scores (OMAS). We analyzed 45 patients who met our study criteria. The patients were divided into 2 groups according to staged surgeries. Demographic data of patients, comorbidities, alcohol and tobacco use, Tscherne soft tissue injury scores, the AOFAS hindfoot-ankle and OMAS, postoperative complications, total hospitalization times, waiting time between stages, and waiting time from admission to surgery times were investigated. There was a statistically significant difference between the groups in terms of the mean total hospitalization times (p = .007), waiting time from admission to surgery (p < .001), gender (p = .005), and Tscherne soft tissue injury scores (p < .001). The mean AOFAS hindfoot-ankle and OMAS of the groups did not differ statistically at a minimum of 12 months of the follow-up period (p = .094 and p = .126, respectively). A 2-stage surgery can be performed safely in the carefully selected patients with the unstable malleolar fracture-dislocations with Tscherne grades 2 and 3 soft tissue injuries, and this surgery does not affect the postoperative AOFAS hindfoot-ankle and OMAS statistically compared to a 1-stage surgery at a minimum of 12 months of the follow-up period.

Biomechanical comparison of three different fixation techniques for anterior column posterior hemitransverse acetabular fractures using anterior intrapelvic approach.

OBJECTIVES: The aim of this study was to biomechanically compare three different fixation methods for the fixation of anterior column posterior hemitransverse type acetabular fracture (ACPHT). METHODS: ACPHT fracture models were created on twenty-four foam cortical shell artificial hemipelvis models. Three fixation methods were assessed - Group 1: posterior column lag screws over a suprapectineal plate; Group 2: Posterior column lag screws over a suprapectineal plate and an infrapectineal plate; Group 3: A suprapectineal plate and a vertical infrapectineal plate. Stiffness and displacement amounts of fixation methods under dynamic and static axial loading conditions were measured. RESULTS: In the dynamic and static tests, Group 3 showed the less stable fixation compared to Group 2. There was no statistically significant difference between the stiffness values of the fixation groups. In the static tests, there was no statistically significant difference between Group 1 and 2, although less displacements were obtained in Group 2. CONCLUSIONS: A combination of posterior lag screws over a suprapectineal plate and an infrapectineal plate supporting the pelvic brim along both sides of the linea terminalis resulted in a better fixation construct than a suprapectineal plate accompanying with a vertical infrapectineal plate provide better stability with less fracture displacement.

Calcaneal Avulsion of an Ochronotic Achilles Tendon: A Case Report.

Alkaptonuria is a hereditary disorder of phenylalanine and tyrosine, with an incidence of approximately 1/200,000 to 1/1,000,000. Ochronosis is the accumulation of homogentisic acid and its metabolites in connective tissues such as the tendons, cartilage, and skin. In the present case study, a 50-year-old male presented with a nontraumatic calcaneal avulsion without a previous diagnosis of ochronosis. To the best of our knowledge, little information has been reported of this pathology in the Achilles tendon and the surgical management.