Larger screw diameter may not guarantee greater pullout strength for headless screws – a biomechanical study
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Chen-Chiang Lin
Abstract
Headless compression screws (HCSs) are commonly utilized devices for small bone fracture fixation. The Mini-Acutrak 2 and headless reduction (HLR) screws are the newer version types, in which both have fully threaded and variable pitch design. Specifically, the HLR is characterized by two thread runouts to facilitate implantation. With the thread runouts, the holding strength of the screw may be compromised. To the best of our knowledge, no study has examined the pullout force of the global sizes of a HCS. We sought to determine the pullout strength of the HLR and compare the strength of this screw with that of the Mini-Acutrak 2. Synthetic bone blocks with simulated transverse fractures were used to conduct the tests. Four commonly used sizes of the HLR were examined, and one Mini-Acutrak 2 was employed for comparison. Five screws of each size were tested. The pullout force of all screws that were tested in this study ranged from 45.23 to 233.22 N. The results revealed that the pullout force increased as the screw diameter increased. Interestingly, we found that one small screw outperformed the Mini-Acutrak 2, which has a larger diameter. This study provided extensive knowledge regarding the pullout strength of fully threaded HCSs of different sizes. An unexpected finding is that a small screw has higher holding power than a large one because of its increased number of threads. Therefore, we suggest that the thread number should be a critical consideration for the design of size distribution of HCSs.
Acknowledgments
We acknowledge the financial support of the Ministry of Science and Technology of Taiwan (MOST 105-2911-I-033-502).
References
[1] ACUTRAK 2 Headless Compression Screw 2005; available at: http://implantesclp.com/uploads/pdf/Acutrak.pdf [Accessed 28 Jan. 2016].Suche in Google Scholar
[2] Assari S, Darvish K, Ilyas AM. Biomechanical analysis of second-generation headless compression screws. Injury 2012; 43: 1159–1165.10.1016/j.injury.2012.03.015Suche in Google Scholar
[3] ASTM F1839-08. Standard specification for rigid polyurethane foam for use as a standard material for testing orthopaedic devices and instruments. American Society for Testing and Materials 2012.Suche in Google Scholar
[4] Bailey C, Kuiper J, Kelly C. Biomechanical evaluation of a new composite bioresorbable screw. J Hand Surg Br 2006; 31: 208.10.1016/J.JHSB.2005.10.015Suche in Google Scholar
[5] Baran O, Sagol E, Oflaz H, Sarikanat M, Havitcioglu H. A biomechanical study on preloaded compression effect on headless screws. Arch Orthop Trauma Surg 2009; 129: 1601–1605.10.1007/s00402-009-0971-0Suche in Google Scholar
[6] Chapman JR, Harrington RM, Lee KM, Anderson PA, Tencer AF, Kowalski D. Factors affecting the pullout strength of cancellous bone screws. J Biomech Eng 1996; 118: 391–398.10.1115/1.2796022Suche in Google Scholar
[7] DeCoster TA, Heetderks DB, Downey DJ, Ferries JS, Jones W. Optimising bone screw pullout force. J Orthop Trauma 1990; 4: 169–174.10.1097/00005131-199004020-00012Suche in Google Scholar
[8] Goldstein SA. The mechanical properties of trabecular bone: dependence on anatomic location and function. J Biomech 1987; 20: 1055–1061.10.1016/0021-9290(87)90023-6Suche in Google Scholar
[9] Haisman JM, Rohde RS, Weiland AJ. Acute fractures of the scaphoid. J Bone Joint Surg Am 2006; 88: 2750–2758.10.2106/00004623-200612000-00026Suche in Google Scholar PubMed
[10] Herbert TJ, Fisher WE. Management of the fractured scaphoid using a new bone screw. J Bone Joint Surg Br 1984; 66: 114–123.10.1302/0301-620X.66B1.6693468Suche in Google Scholar PubMed
[11] Huebner RJ, Conrad GL, Jensen DG. Variable pitch bone screw. USA Patent Document. 1999: 5, 871, 486.Suche in Google Scholar
[12] Ramaswamy R, Evans S, Kosashvili Y. Holding power of variable pitch screws in osteoporotic, osteopenic and normal bone: are all screws created equal? Injury 2010; 41: 179–183.10.1016/j.injury.2009.08.015Suche in Google Scholar PubMed
[13] Sano S, Rokkaku T, Saito S, Tokunaga S, Abe Y, Moriya H. Herbert screw fixation of capitellar fractures. J Shoulder Elbow Surg 2005; 14: 307–311.10.1016/j.jse.2004.09.005Suche in Google Scholar PubMed
[14] Wheeler DL, McLoughlin SW. Biomechanical assessment of compression screws. Clin Orthop Relat Res 1998; 350: 237–245.10.1097/00003086-199805000-00032Suche in Google Scholar
[15] Whipple TL. Stabilisation of the fractured scaphoid under arthroscopic control. Orthop Clin North Am 1995; 26: 749–754.10.1016/S0030-5898(20)32035-6Suche in Google Scholar
©2017 Walter de Gruyter GmbH, Berlin/Boston
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Artikel in diesem Heft
- Frontmatter
- Review
- Bone plates for osteosynthesis – a systematic review of test methods and parameters for biomechanical testing
- Research articles
- Computer assisted evaluation of plate osteosynthesis of diaphyseal femur fracture considering interfragmentary movement: a finite element study
- Larger screw diameter may not guarantee greater pullout strength for headless screws – a biomechanical study
- Design considerations for patient-specific surgical templates for total hip arthroplasty with respect to acetabular cartilage
- Migration measurement of the cemented Lubinus SP II hip stem – a 10-year follow-up using radiostereometric analysis
- Shear stress and von Mises stress distributions in the periphery of an embedded acetabular cup implant during impingement
- Mechanical properties of contemporary orthodontic adhesives used for lingual fixed retention
- Extraordinary biological properties of a new calcium hydroxyapatite/poly(lactide-co-glycolide)-based scaffold confirmed by in vivo investigation
- Feasibility study of using a Microsoft Kinect for virtual coaching of wheelchair transfer techniques
- Accuracy of leg alignment measurements from antero-posterior radiographs
- Holoentropy enabled-decision tree for automatic classification of diabetic retinopathy using retinal fundus images
- Pattern recognition of enrichment levels of SELEX-based candidate aptamers for human C-reactive protein
- Source localization of S-cone and L/M-cone driven signals using silent substitution flash stimulation
