The Biomechanical Strength of the Sacral Reconstruction After Total Sacrectomy Utilizing Bilateral Fibular A-Frame or Truss Technique

Assessment of osteoporosis-associated fracture risk during clinical routine is based on the evaluation of clinical risk factors and T-scores, as derived from measurements of areal bone mineral density (aBMD). However, these parameters are limited in their ability to identify patients at high fracture risk. Finite element models (FEMs) have shown to improve bone strength prediction beyond aBMD. This study aims to investigate whether FEM measurements at the lumbar spine can predict the biomechanical strength of functional spinal units (FSUs) with incidental osteoporotic vertebral fractures (VFs) along the thoracolumbar spine. Multi-detector computed tomography (MDCT) data of 11 patients (5 females and 6 males, median age: 67 years) who underwent MDCT twice (median interval between baseline and follow-up MDCT: 18 months) and sustained an incidental osteoporotic VF between baseline and follow-up scanning were used. Based on baseline MDCT data, two FSUs consisting of vertebral bodies and intervertebral discs (IVDs) were modeled: one standardly capturing L1-IVD–L2-IVD–L3 (FSU_L1–L3) and one modeling the incidentally fractured vertebral body at the center of the FSU (FSU_F). Furthermore, volumetric BMD (vBMD) derived from MDCT, FEM-based displacement, and FEM-based load of the single vertebrae L1 to L3 were determined. Statistically significant correlations (adjusted for a BMD ratio of fracture/L1–L3 segments) were revealed between the FSU_F and mean load of L1 to L3 (r = 0.814, p = 0.004) and the mean vBMD of L1 to L3 (r = 0.745, p = 0.013), whereas there was no statistically significant association between the FSU_F and FSU_L1–L3 or between FSU_F and the mean displacement of L1 to L3 (p > 0.05). In conclusion, FEM measurements of single vertebrae at the lumbar spine may be able to predict the biomechanical strength of incidentally fractured vertebral segments along the thoracolumbar spine, while FSUs seem to predict only segment-specific fracture risk.

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Looped suture properties: implications for multistranded flexor tendon repair

Journal of Hand Surgery (European Volume) ◽

10.1177/1753193413516245 ◽

2015 ◽

Vol 40 (3) ◽

pp. 234-238 ◽

Cited By ~ 6

Author(s):

R. Haddad ◽

T. Peltz ◽

N. Bertollo ◽

W. R. Walsh ◽

S. Nicklin

Keyword(s):

Mechanical Properties ◽

Flexor Tendon ◽

Tendon Repair ◽

Relative Effect ◽

Flexor Tendon Repair ◽

Polypropylene Monofilament ◽

Single Suture ◽

Biomechanical Strength ◽

Standard Techniques ◽

Repair Techniques

Multiple-strand repair techniques are commonly used to repair cut flexor tendons to achieve initial biomechanical strength. Looped sutures achieve multiple strands with fewer passes and less technical complexity. Their biomechanical performance in comparison with an equivalent repair using a single-stranded suture is uncertain. This study examined the mechanical properties of double-stranded loops of 3-0 and 4-0 braided polyester (Ticron) and polypropylene monofilament (Prolene). Double loops were generally less than twice the strength of a single loop. Ticron and Prolene had the same strengths, but Ticron was stiffer. The 4-0 double loops had significantly higher stiffness than 3-0 single loops. Increasing the size of sutures had a larger relative effect on strength than using a double-stranded suture. However, a double-strand loop had a larger effect on increasing stiffness than using a single suture of a larger equivalent size. Looped suture repairs should be compared with standard techniques using a thicker single suture.

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Biomechanical Strength of Screw Versus Suture Button Fixation in the Latarjet Procedure: A Cadaver Study

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2021.03.079 ◽

2021 ◽

Vol 30 (7) ◽

pp. e449

Author(s):

Gazi Huri ◽

Yasin Hakverdiyev ◽

Mehmet Kaymakoglu ◽

Erdi Ozdemir ◽

Pinar Yilgor Huri ◽

...

Keyword(s):

Cadaver Study ◽

Latarjet Procedure ◽

Suture Button ◽

Biomechanical Strength

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Biomechanical Evaluation of Supplemental Percutaneous Lumbo-Sacro-Iliac Screws for Spinopelvic Fixation Following Total Sacrectomy

Journal of Spinal Disorders & Techniques ◽

10.1097/bsd.0000000000000241 ◽

2015 ◽

Vol 28 (4) ◽

pp. E181-E185 ◽

Cited By ~ 4

Author(s):

Vu H. Le ◽

Nathanael Heckmann ◽

Nickul Jain ◽

Lawrence Wang ◽

Alexander W. L. Turner ◽

...

Keyword(s):

Spinopelvic Fixation ◽

Iliac Screws ◽

Biomechanical Evaluation ◽

Total Sacrectomy

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Comprehensive Biomechanical Analysis of Three Lumbopelvic Reconstruction Techniques following Total Sacrectomy: An In Vitro Human Cadaveric Model

The Spine Journal ◽

10.1016/j.spinee.2016.07.061 ◽

2016 ◽

Vol 16 (10) ◽

pp. S161

Author(s):

Bryan W. Cunningham ◽

Mohamad Bydon ◽

Ashley A. Murgatroyd ◽

Kenneth Mullinix ◽

Ziya L. Gokaslan ◽

...

Keyword(s):

Biomechanical Analysis ◽

Total Sacrectomy ◽

Cadaveric Model

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The Effect of Suture Materials on the Biomechanical Performance of Different Flexor Tendon Repairs and the Concept of Construct Efficiency

The Journal of Hand Surgery (Asian-Pacific Volume) ◽

10.1142/s2424835518500285 ◽

2018 ◽

Vol 23 (02) ◽

pp. 243-247

Author(s):

Yoke Rung Wong ◽

Austin Mun Kitt Loke ◽

Shian Chao Tay

Keyword(s):

Tensile Strength ◽

Ultimate Tensile Strength ◽

Tensile Testing ◽

Flexor Tendon ◽

Experimental Results ◽

Suture Materials ◽

Nylon Suture ◽

Biomechanical Strength ◽

Repair Techniques

Background: To propose a new term (‘construct efficiency’) for the evaluation of multi strands flexor tendon repairs using different suture materials. Methods: A total of twenty specimens from 4-0 braided polyblend sutures (FiberLoop/FiberWire; Arthrex, Naples, FL) and 4-0 nylon sutures (Supramid Extra II; S. Jackson, Inc., Alexandria, VA) were subjected to tensile testing using Pneumatic Cord-and-Yarn Grips (Instron Corp., Canton MA, USA). The ultimate tensile strengths of the suture materials were measured. The expected repair strengths and construct efficiencies were computed based on the experimental results and from available literature on actual repair strengths of the 4-strand Becker, Cruciate repairs and 6-strand Tang, modified Lim-Tsai repairs. Results: The ultimate tensile strength of nylon suture was 15.4 ± 0.6N, lower than that of braided polyblend suture (45.3 ± 2.3N) with a difference of 194%. The construct efficiency of multi strand repairs varied with respect to different repair techniques and suture materials. It was found that the Becker repairs using FiberWire had the highest construct efficiency (55.7%) followed by the modified Lim-Tsai using Supramid (50.9%), Tang repair using Supramid (49.8%), Cruciate repair using Fiberwire (49.1%), and modified Lim-Tsai repair using FiberLoop (33.5%). Conclusions: The construct efficiency is more accurate in showing that, in terms of biomechanical strength, the use of FiberWire for the 4-strand Becker and Cruciate repair is more efficient than that of using FiberLoop for 6-strand modified Lim-Tsai repair.

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Correction of refractive disorders in the surgical treatment of keratoconus by MyoRing implantation

Modern technologies in ophtalmology ◽

10.25276/2312-4911-2021-5-188-191 ◽

2021 ◽

pp. 188-191

Author(s):

S.V. Milova ◽

◽

A. Daxer ◽

Keyword(s):

Visual Acuity ◽

Surgical Treatment ◽

Key Words ◽

Corneal Stroma ◽

Degenerative Disease ◽

Corrected Visual Acuity ◽

Corneal Deformation ◽

Biomechanical Strength ◽

Observation Period

Keratoconus is a progressive degenerative disease in which, due to the weakening of the biomechanical strength of the cornea, its cone-shaped deformation occurs, leading to the development of induced myopia and astigmatism, as well as to a decrease in corrected visual acuity. Treatment of this disease consists in achieving stabilization of the process by strengthening the structure of the cornea, as well as in correcting refractive disorders caused by corneal deformation. Purpose. The purpose is to evaluate the effectiveness of correction of refractive disorders by implanting a closed MyoRing ring in the corneal stroma of patients with keratoconus. Material and methods. The data of 98 MyoRing implantation operations using CISIS technology using the PoketMaker ultraceratom for stage 3-4 keratoconus were analyzed. The observation period is up to 9 years. The initial myopia averaged -9.23 D ±3.82, astigmatism-6.13 ±2.51. Results. Stabilization of the refractive effect occurred usually within 3-6 months after surgery. On average, the following correction of refractive disorders was achieved: myopia-8.14 D ± 2.67 and astigmatism-4.28 D ± 2.12. Keratometry indicators also in most cases stabilized within 3-6 months after surgery and remained unchanged throughout the entire follow-up period. Conclusions. Implantation of a closed MyoRing ring in keratoconus makes it possible to significantly correct refractive disorders and prevents further progression of the disease. Key words: keratoconus, MyoRing, SISI, ring implantation in keratoconus.

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