Introduction: In 2019, Moufid and Gille published a study in which they proposed certain radiological parameters that may justify the mismatch between the lordosis of the lumbar segment and the lordosis of the rod bar using polyaxial screws. The aim of this study is to reproduce the measurements performed by Moufid and Gille and try to validate their findings.

Material And Methods: A retrospective study was performed including patients submitted to L3-L5 posterior fusion with or without interbody devices using polyaxial screws and titanium rods, for degenerative disease. Radiological parameters were analysed:the distance between the posterior wall and the rod for each vertebra(the standard deviation of the three distances was called Alpha); the angle between the screw and the rod for each screw(mean of the three was called Theta); the angle between screws and superior endplate for each instrumented vertebra(mean of the three was called Lambda). The difference between post-operative segmental lordosis and the lordosis of the rod was called DiffL.

Results: A total of 58 cases were included. The most frequent fusion surgery was posterolateral fusion(77.6%). The mean value of lumbar lordosis, fused segmental lordosis, pelvic incidence, Alpha, Theta, Lambda and DiffL were 48.7 ± 12.7°, 28.4 ± 9.2°, 60.7 ± 11.9°, 3.4 ± 1.6 mm, 90.5 ± 1.8°, 3.9 ± 1.8° e 9.9 ± 9.5° respectively. The mean value of rod lordosis was 20.5 ± 8.1°. DiffL varied between 0.1° (practically no mismatch) and 30.5° of mismatch. DiffL didn't correlate with gender, fusion type, age, PI and Alpha, Theta or Lambda. There was a significant positive correlation between lumbar lordosis and DiffL( 0.28; p = 0.03). No correlation was found between the radiological parameters for the cut-off point proposed by Moufid and Gille(Alpha 4.7 mm, Theta 86°, Lambda 2.8°) and the DiffL value.

Conclusion: No significant factors were identified in this study to aid in achieving an ideal match between rod and segmental spine lordosis, therefore not validating the study by Moufid and Gille.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9357705PMC
http://dx.doi.org/10.1016/j.jor.2022.07.021DOI Listing

Publication Analysis

Top Keywords

polyaxial screws
12
moufid gille
12
radiological parameters
12
lordosis
9
fusion surgery
8
lordosis rod
8
three called
8
segmental lordosis
8
lumbar lordosis
8
alpha theta
8

Similar Publications

Introduction Spinal fusion surgery with pedicle screws is commonly performed to stabilize the spine of osteoporotic patients. However, securing a strong screw fixation in osteoporotic bone presents significant challenges due to the reduced bone density. This study aimed to compare the biomechanical performance in an osteoporotic bone model of pedicle screws inserted using two different techniques, the Jamshidi needle technique and the pedicle probe technique, as well as the influence of tapping on both these techniques.

View Article and Find Full Text PDF

Advancements in the Management of Fragility Fractures in Orthopaedic Patients.

Cureus

November 2024

Orthopaedics, Glasgow Royal Infirmary, Glasgow, GBR.

Osteoporosis is a major risk factor for fragility fractures. The British Orthopaedics Association Standards for Trauma and Orthopaedics (BOAST) and Getting it Right First Time (GIRFT) guidelines on fragility fracture management highlight the need to initiate prompt, coordinated multidisciplinary care with a focus on early mobilisation to improve patient outcomes. Medical management of fragility fractures focuses on the prevention of progressive frailty.

View Article and Find Full Text PDF

Background Vertebral hemangiomas (VHs) are benign vascular tumors commonly found within the vertebral bodies of the spine. While most VHs remain asymptomatic and are often discovered incidentally during imaging studies, a subset can become symptomatic, leading to clinical challenges. The optimal treatment approach for symptomatic VHs remains a topic of debate.

View Article and Find Full Text PDF

 To avoid screw penetration into the joint when using the polyaxial volar locking plate (VLP) for osteosynthesis of distal radius fractures, it is important to note that the optimal screw insertion angles depending on the plate positions.  The purpose of this study was 2-fold: first, to evaluate the differences of the most distal plate position where the screw does not penetrate into the joint in the three-dimensional (3D) radius models; second, to evaluate the relationship between the plate position and the transverse diameter of the distal radius.  Thirty plain X-rays and computed tomography (CT) scans of healthy wrists were evaluated.

View Article and Find Full Text PDF
Article Synopsis
  • Polyaxial locking systems are commonly utilized in surgeries for challenging cases, such as osteoporotic bones or complicated fractures, but they may decrease stiffness compared to standard designs.
  • A new plate design featuring narrow construction with asymmetric holes and polyaxial capabilities was tested against traditional narrow plates, using three settings with different screw orientations.
  • The results revealed that while polyaxial systems improve surgical placement flexibility, they incur a reduction in torsional strength; however, all groups maintained a strong screw-plate connection even under stress.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!