scholarly journals Effect of Screw Length and Geometry on Interfragmentary Compression in a Simulated Proximal Pole Scaphoid Fracture Model

Hand ◽  
2018 ◽  
Vol 15 (3) ◽  
pp. 378-383
Author(s):  
Samik Patel ◽  
Juan M. Giugale ◽  
Richard E. Debski ◽  
John R. Fowler
Keyword(s):  
Analysis Of Variance ◽  
Scaphoid Fracture ◽  
Fracture Site ◽  
Proximal Pole ◽  
Scaphoid Fractures ◽  
Screw Length ◽  
Significant Difference ◽  
Headless Compression Screws ◽  
With Screws ◽  
Interfragmentary Compression

Background: The objective of this study was to determine interfragmentary compression forces based on screw length and geometry for simulated proximal scaphoid fractures. Methods: Sixty-four foam model simulated fractures were stabilized with screws of various length (10 mm, 18 mm, 20 mm, or 24 mm) and geometry (central threadless or fully threaded) across a proximal fracture. Interfragmentary compression was measured at the simulated fracture site upon fixation. An independent sample t test and 1-way analysis of variance were performed to assess differences in interfragmentary compression. Results: Fixation utilizing a 10-mm screw generated significantly less interfragmentary compression than fixation utilizing a 20-mm or 24-mm screw. When accounting for both screw length and geometry, an 18-mm central threadless screw generated greater interfragmentary compression than a 20-mm and 24-mm fully threaded screw; there was no significant difference in compression between an 18-mm and 24-mm central threadless screw. Conclusions: The design of headless compression screws allows for maximal interfragmentary compression at the screw midpoint; we questioned whether a short screw centered on the fracture site resulted in superior compression to a longer, noncentered screw. Our data suggest that centering a small screw (10 mm) along a proximal fracture generates significantly less interfragmentary compression than a longer, noncentered screw. Our results demonstrate that balance between maximizing screw length and centering the screw on the fracture is vital toward maximizing interfragmentary compression for the fixation of proximal third scaphoid fractures.

scholarly journals Impact of Screw Length on Proximal Scaphoid Fracture Biomechanics

2019 ◽  
Vol 08 (05) ◽  
pp. 360-365 ◽  
Author(s):  
Samik Patel ◽  
Juan Giugale ◽  
Nathan Tiedeken ◽  
Richard E. Debski ◽  
John R. Fowler
Keyword(s):  
Cyclic Loading ◽  
Fracture Fixation ◽  
Ultimate Load ◽  
Scaphoid Fracture ◽  
Fracture Site ◽  
Compression Screw ◽  
Headless Compression Screw ◽  
Scaphoid Fractures ◽  
Screw Length ◽  
Significant Difference

Background Proximal scaphoid fractures display high nonunion rates and increased revision cases. Waist fracture fixation involves maximizing screw length within the cortex; however, the optimal screw length for proximal scaphoid fractures remains unknown. Purpose The main purpose of this article is to compare stiffness and ultimate load for proximal scaphoid fracture fixation of various headless compression screw lengths. Methods Eighteen scaphoids underwent an osteotomy simulating a 7 mm oblique proximal fracture. Screws of three lengths (10, 18, and 24 mm) were randomly assigned for fixation. Each specimen underwent cyclic loading with stiffness calculated during the last loading cycle. Specimens that withstood cyclic loading were loaded to failure. Results No significant difference in stiffness between screw lengths was found. Ultimate load was significantly impacted by the screw length. A significant difference in ultimate load between a 10 and 24 mm screw was found; however, no significant difference occurred in ultimate load between an 18 and 24 mm screw. Conclusions No significant difference in stiffness between all groups could be due to similarities in purchase in the proximal aspect. The 10 mm screw withstanding less ultimate load compared to the 24 mm screw could be due to the 10 mm screw gaining less purchase on either side of the fracture site compared to the 24 mm screw. Lack of significant difference in ultimate load between the 18 and 24 mm screw could be occurring because the fracture site is closer to the 18 mm screw midpoint, as distal threads are engaged closer to the fracture. Clinical Relevance Maximizing screw length may not provide superior fixation biomechanically compared with fixation utilizing a 6 mm shorter screw for proximal scaphoid fractures.

scholarly journals Pronator quadratus pedicled bone graft for scaphoid non-unions

2020 ◽  
Vol 7 (10) ◽  
pp. 3414
Author(s):  
Harsha Vardhan ◽  
Anto Francis
Keyword(s):  
Bone Graft ◽  
Fracture Healing ◽  
Scaphoid Fracture ◽  
Fracture Site ◽  
Vascularized Bone Graft ◽  
Proximal Pole ◽  
Pronator Quadratus ◽  
Scaphoid Fractures ◽  
Fracture Nonunion ◽  
Vascularized Bone

Scaphoid fractures frequently present with nonunion and proximal pole necrosis, the treatment of which is bone grafting. Pronator quadratus pedicled vascularized bone graft is an option especially in the setting of proximal pole necrosis. We describe our experience of managing such scaphoid non-unions using pronator quadratus pedicled vascularized bone graft. Six patients were managed using pronator quadratus pedicled vascularized bone graft following scaphoid fracture nonunion with proximal pole necrosis. All patients had good fracture healing and symptom resolution. Mild deficit in wrist extension was noted in all patients. Pronator quadratus pedicled vascularized bone graft is an attractive option for managing scaphoid nonunion. Lying adjacent to the fracture site, bone can be harvested and transferred without making any other incisions. This procedure introduces another source of blood supply to the fracture site and hence improves fracture healing.

Real Time Ultrasonography in the Assessment of Movement at the Site of a Scaphoid Fracture Non-Union

1994 ◽  
Vol 19 (4) ◽  
pp. 498-504 ◽  
Author(s):  
J. J. DIAS ◽  
A. C. W. HUI ◽  
A. C. LAMONT
Keyword(s):  
Surgical Treatment ◽  
Real Time ◽  
Scaphoid Fracture ◽  
Fracture Site ◽  
Proximal Pole ◽  
Non Union ◽  
Non Invasive ◽  
Scaphoid Fractures ◽  
Time Linear ◽  
Real Time Ultrasonography

We investigated the use of real time linear ultrasonography in determining movement at a scaphoid fracture site in 27 patients with non-united scaphoid fractures. 24 of these patients had surgical treatment. Fracture movement was observed at the time of surgery and this was compared with the ultrasonographic findings. The technique proved to be 100% specific for visualization of movement at the fracture site and it was non-invasive. However, it was of no benefit in assessing proximal pole non-union.

scholarly journals Biomechanical Strength of Retrograde Fixation in Proximal Third Scaphoid Fractures

Hand ◽  
2018 ◽  
Vol 14 (6) ◽  
pp. 760-764 ◽  
Author(s):  
Charles A. Daly ◽  
Allison L. Boden ◽  
William C. Hutton ◽  
Michael B. Gottschalk
Keyword(s):  
Cyclic Loading ◽  
Scaphoid Fracture ◽  
Maximum Load ◽  
Vascular Supply ◽  
Proximal Pole ◽  
Wrist Fractures ◽  
Scaphoid Fractures ◽  
Screw Length ◽  
Load To Failure ◽  
Biomechanical Strength

Background: Current techniques for fixation of proximal pole scaphoid fractures utilize antegrade fixation via a dorsal approach endangering the delicate vascular supply of the dorsal scaphoid. Volar and dorsal approaches demonstrate equivalent clinical outcomes in scaphoid wrist fractures, but no study has evaluated the biomechanical strength for fractures of the proximal pole. This study compares biomechanical strength of antegrade and retrograde fixation for fractures of the proximal pole of the scaphoid. Methods: A simulated proximal pole scaphoid fracture was produced in 22 matched cadaveric scaphoids, which were then assigned randomly to either antegrade or retrograde fixation with a cannulated headless compression screw. Cyclic loading and load to failure testing were performed and screw length, number of cycles, and maximum load sustained were recorded. Results: There were no significant differences in average screw length (25.5 mm vs 25.6 mm, P = .934), average number of cyclic loading cycles (3738 vs 3847, P = .552), average load to failure (348 N vs 371 N, P = .357), and number of catastrophic failures observed between the antegrade and retrograde fixation groups (3 in each). Practical equivalence between the 2 groups was calculated and the 2 groups were demonstrated to be practically equivalent (upper threshold P = .010). Conclusions: For this model of proximal pole scaphoid wrist fractures, antegrade and retrograde screw configuration have been proven to be equivalent in terms of biomechanical strength. With further clinical study, we hope surgeons will be able to make their decision for fixation technique based on approaches to bone grafting, concern for tenuous blood supply, and surgeon preference without fear of poor biomechanical properties.

The morphology of proximal pole scaphoid fractures: implications for optimal screw placement

2017 ◽  
Vol 43 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Timothy J. Luchetti ◽  
Youssef Hedroug ◽  
John J. Fernandez ◽  
Mark S. Cohen ◽  
Robert W. Wysocki
Keyword(s):  
Sagittal Plane ◽  
Fracture Line ◽  
Screw Thread ◽  
Proximal Pole ◽  
Screw Insertion ◽  
Scaphoid Fractures ◽  
Starting Point ◽  
Screw Length ◽  
Sagittal Image ◽  
The Ideal

The purpose of this study was to measure the radiographic parameters of proximal pole scaphoid fractures, and calculate the ideal starting points and trajectories for antegrade screw insertion. Computed tomography scans of 19 consecutive patients with proximal pole fractures were studied using open source digital imaging and communications in medicine (DICOM) imaging measurement software. For scaphoid sagittal measurements, fracture inclination was measured with respect to the scaphoid axis. The ideal starting point for a screw in the proximal pole fragment was then identified on the scaphoid sagittal image that demonstrated the largest dimensions of the proximal pole, and hence the greatest screw thread purchase. Measurements were then taken for a standard screw trajectory in the axis of the scaphoid, and a trajectory that was perpendicular to the fracture line. The fracture inclination in the scaphoid sagittal plane was 25 (SD10) °, lying from proximal palmar to dorsal distal. The fracture inclination in the coronal plane was 9 (SD16) °, angling distal radial to proximal ulnar with reference to the coronal axis of the scaphoid. Using an ideal starting point that maximized the thread purchase in the proximal pole, we measured a maximum screw length of 20 (SD 2) mm when using a screw trajectory that was perpendicular to the fracture line. This was quite different from the same measurements taken in a trajectory in the axis of the scaphoid. We also identified a mean distance of approximately 10 mm from the dorsal fracture line to the ideal starting point. A precise understanding of this anatomy is critical when treating proximal pole scaphoid fractures surgically.

scholarly journals Pediatric Scaphoid Nonunions: A Case Series, Review of the Literature, and Evidence-Based Guidelines

2019 ◽  
Vol 09 (01) ◽  
pp. 002-012 ◽  
Author(s):  
Kerstin Oestreich ◽  
Tatiana Umata Yoko Jacomel ◽  
Sami Hassan ◽  
Maxim David Horwitz ◽  
Tommy Roger Lindau
Keyword(s):  
Nonoperative Management ◽  
Pediatric Population ◽  
Scaphoid Fracture ◽  
Case Series ◽  
Fracture Site ◽  
X Rays ◽  
Review Of The Literature ◽  
Level Of Evidence ◽  
Scaphoid Fractures ◽  
Magnetic Resonance Imaging Mri

Abstract Background Scaphoid fractures represent less than 3% of hand and wrist fractures in the pediatric population. Nonunions are very rare. We present a case series (n = 18) of nonunions in skeletally immature children and adolescents. We further present a review of the literature on pediatric scaphoid nonunions. Materials and Methods We reviewed the literature by searching the main databases on pediatric scaphoid nonunions, but to identify factors that lead to nonunion, we also searched for databases on scaphoid fractures. Seventy articles were found for the period between 1961 and 2019, all with level 4/5 evidence. Results The nonunion rate of pediatric scaphoid fractures in the literature is on average 1.5%, occurring mostly as a result of missed or underdiagnosed injuries, similar to our presented case series. Half (n = 9) of the injuries in our case series were missed initial injuries, leading to scaphoid nonunions and half developed nonunions after initial treatment. We found excellent outcomes and with surgical and nonoperative management, with few complications. Not surprisingly, the duration of immobilization is longer with nonoperative management. Conclusions Based on the literature, we recommend a period of nonoperative management before surgery in undisplaced nonunions. In displaced nonunions, open reduction and internal fixation ± bone grafting is necessary. In pediatric scaphoid fractures, similar to adult cases, we identified that suspicious scaphoid fractures should be considered for initial immobilization, and repeat X-rays and early magnetic resonance imaging (MRI) or computed tomography (CT) scans should be considered at follow-up. Immobilization time and type of plaster should be appropriate in relation to the fracture site, similar to the adult scaphoid fracture. Level of Evidence This is a Level IV study.

Gadolinium Enhanced Mr Assessment of Proximal Fragment Vascularity in Nonunions after Scaphoid Fracture: Does It Predict the Outcome of Reconstructive Surgery?

2004 ◽  
Vol 29 (5) ◽  
pp. 444-448 ◽  
Author(s):  
A.K. SINGH ◽  
T.R.C. DAVIS ◽  
J.S. DAWSON ◽  
J.A. ONI ◽  
N.D. DOWNING
Keyword(s):  
Internal Fixation ◽  
Reconstructive Surgery ◽  
Scaphoid Fracture ◽  
Proximal Fragment ◽  
Proximal Pole ◽  
Scaphoid Fractures ◽  
Fracture Nonunion ◽  
Fracture Nonunions ◽  
Outcome Of Surgery ◽  
Mr Scanning

This study investigated whether the outcome of bone graft and internal fixation surgery for nonunion of scaphoid fractures could be predicted by gadolinium-enhanced MR assessments of proximal fragment vascularity. Sixteen established scaphoid fracture nonunions underwent gadolinium-enhanced MR scanning before surgical treatment with bone grafting and internal fixation. No relationship was found between MR enhancement and the outcome of surgery. Union was achieved in eight of the 12 nonunions with more than 50% enhancement, and three of the four with less than 50% enhancement, of the proximal pole. Furthermore, union was achieved in both of the nonunions which had less than 25% enhancement of the proximal pole. We conclude that enhanced MR assessments of the vascularity of the proximal fragment of a scaphoid fracture nonunion do not accurately predict the outcome of reconstructive surgery.

scholarly journals Dual-energy CT in the diagnosis of occult acute scaphoid injury: a direct comparison with MRI

2020 ◽  
Author(s):  
Cheng Xie ◽  
Sarim Ather ◽  
Ramy Mansour ◽  
Fergus Gleeson ◽  
Rajat Chowdhury
Keyword(s):  
Bone Marrow ◽  
Scaphoid Fracture ◽  
Dual Energy ◽  
Bone Marrow Oedema ◽  
Dual Energy Ct ◽  
Contrast Resolution ◽  
Scaphoid Fractures ◽  
Key Points ◽  
Significant Difference ◽  
Lower Contrast

Abstract Objectives Scaphoid injuries occult on plain radiography often require further imaging for definitive diagnosis. We investigate the utility of dual-energy computed tomography (DECT) for the detection of acute bone marrow oedema and fracture of scaphoid compared to MRI. Materials and methods Twenty patients who presented acutely (without prior injury) to the emergency department with clinically suspected occult scaphoid fracture and had MRI of the wrist were prospectively recruited to have DECT (GE Revolution CT). Material decomposition images of the water-calcium base pair were generated and assessed in conjunction with the monochromatic images to permit correlation of marrow signal changes with any cortical disruption for fracture confirmation. The assessment was performed by two musculoskeletal radiologists blinded from MRI results. The statistical difference of MRI and reviewers’ detection of acute bone oedema (1 = present, 0 = absent) was performed using the Friedman test (SPSS v.16). Results MRI showed acute scaphoid fracture and/or bone marrow oedema in 14/20 patients of which 6 also had cortical disruption. On DECT, reviewer A identified oedema in 13 and cortical disruption in 10 patients while reviewer B identified oedema in 10 and cortical disruption in seven of the 14 MRI positive patients. No statistically significant difference in oedema detection on MRI and reviewers of DECT (p value 0.61) but DECT was more sensitive at detecting cortical disruption. Conclusion DECT has the capability to detect acute scaphoid oedema in addition to cortical fractures. However, compared to MRI, DECT has lower contrast resolution and less sensitive in the detection of mild oedema. Key Points • Dual-energy CT is able to detect acute traumatic scaphoid marrow oedema. • Dual-energy CT has greater detection rate of scaphoid fractures than MRI. • Dual-energy CT is an alternative to MRI for occult scaphoid injury.

scholarly journals Scaphoid Fracture Patterns—Part Two: Reproducibility and Demographics of a Simplified Scaphoid Fracture Classification

2019 ◽  
Vol 08 (06) ◽  
pp. 446-451
Author(s):  
Tessa Drijkoningen ◽  
Amin Mohamadi ◽  
Wouter F. van Leeuwen ◽  
Yonatan Schwarcz ◽  
David Ring ◽  
...  
Keyword(s):  
Electronic Medical Records ◽  
Medical Records ◽  
Interobserver Reliability ◽  
Scaphoid Fracture ◽  
Fracture Classification ◽  
Proximal Pole ◽  
Level Of Evidence ◽  
Related Factors ◽  
Scaphoid Fractures ◽  
Fracture Patterns

Abstract Objective To analyze the reproducibility, reliability, and demographics of a simplified anatomical scaphoid fracture classification based on posteroanterior radiographs using a large database of scaphoid fractures. Methods The study consisted of a retrospective review of electronic medical records of 871 consecutive patients. All patients presented between 2003 and 2014 at two centers. Patient- and surgeon-related factors were analyzed. Additionally, interobserver reliability of the Herbert and simplified scaphoid fracture classifications were tested. Results Proximal pole fractures were defined as fractures in which the center of the fracture line was proximal to the distal scapholunate interval (n = 30), waist fractures (n = 802) were defined as fractures involving the scaphocapitate interval, and distal tubercle fractures (n = 39) were defined as fractures involving the scaphotrapeziotrapezoid (STT) interval. The interobserver reliability of the simplified classification was fair (κ = 0.37) as for the Herbert classification (κ = 0.31). The average doubt of the answers of the observers was 2.1 on a scale from 0 to 10 for the simplified classification and 3.6 for the Herbert classification (P < 0.05). Conclusions All complete fractures across the entire scaphoid distal to the scapholunate articulation and proximal to the STT joint can be classified as waist fractures; nonwaist scaphoid fractures are uncommon (6%) and have somewhat different presentations compared to waist fractures. Simplifying the fracture classification slightly improves interobserver reliability, although remaining fair, and significantly reduces doubt. Level of Evidence This is a Level III, prognostic study.

Ulnar Variance in Scaphoid Fractures: Retrospective Analysis of 182 Cases

2019 ◽  
Vol 24 (01) ◽  
pp. 13-16
Author(s):  
Rik Osinga ◽  
L. Estermann ◽  
H.J. Klein ◽  
S. Schibli-Beer ◽  
A.R. Jandali ◽  
...  
Keyword(s):  
Scaphoid Fracture ◽  
Ulnar Variance ◽  
Control Group ◽  
University Hospitals ◽  
Fracture Group ◽  
Paired Sample ◽  
Scaphoid Fractures ◽  
Number Of Patients ◽  
Gender And Age ◽  
Significant Difference

Background: Literature provides little and controversial evidence regarding the influence of ulnar variance (UV) on the incidence of scaphoid fractures. The aim of this retrospective study was to assess UV in a large number of patients with acute scaphoid fracture in comparison to a control group of the same population. Methods: During a two year period, 182 patients with acute scaphoid fractures (fracture group) and 182 ethnicity-, gender- and age-matched patients with wrist contusions (control group) were treated in three non-university hospitals. Using standardized digital wrist radiographs, UV values were measured by means of the method of perpendiculars by two independent examiners. The UV values of the fracture group were then compared to the UV values of the control group. Results: Analyses of the agreement between the two raters resulted in a good to excellent inter-item correlation of 0.89, with a high intra-class coefficient of 0.93 (95% confidence interval: 0.87–0.95). Mean (SD) UV value was -0.82 mm (1.77) in the fracture group and 0.27 mm (1.44) in the control group. Paired sample t-test showed a significant difference between the two groups (p < 0.0001). Conclusions: According to this study, patients with scaphoid fractures are significantly more likely to show a negative UV than matched patients with wrist contusions.

Sign in / Sign up

Export Citation Format

Share Document