1
|
Chiu YC, Ho TY, Hsu CE, Yeh CW, Ting YN, Tsai MT, Hsu JT. Biomechanical analysis of plate versus K-wire fixation for metacarpal shaft fractures with wedge-shaped bone defects. BMC Musculoskelet Disord 2024; 25:350. [PMID: 38702748 PMCID: PMC11067226 DOI: 10.1186/s12891-024-07482-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 04/29/2024] [Indexed: 05/06/2024] Open
Abstract
BACKGROUND Metacarpal shaft fracture is a common type of hand fracture. Numerous studies have explored fixing transverse fractures in the midshaft of the metacarpal bone. However, this section of the metacarpal bone is often susceptible to high-energy injury, resulting in comminuted fracture or bone loss. In such cases, wedge-shaped bone defects can develop in the metacarpal shaft, increasing the difficulty of performing fracture fixation. Notably, the research on this type of fracture fixation is limited. This study compared the abilities of four fixation methods to fix metacarpal shaft fractures with wedge-shaped bone defects. METHODS In total, 28 artificial metacarpal bones were used. To create wedge-shaped bone defects, an electric saw was used to create metacarpal shaft fractures at the midshaft of each bone. The artificial metacarpal bones were then divided into four groups for fixation. The bones in the first group were fixed with a dorsal locked plate (DP group), those in the second group were fixed with a volar locked plate (VP group), and those in the third group were fixed by combining dorsal and volar locked plates (DP + VP group), and those in the fourth group were fixed with two K-wires (2 K group). Cantilever bending tests were conducted using a material testing machine to measure yielding force and stiffness. The four groups' fixation capabilities were then assessed through analysis of variance and Tukey's test. RESULTS The DP + VP group (164.1±44.0 N) achieved a significantly higher yielding force relative to the 2 K group (50.7 ± 8.9 N); the DP group (13.6 ± 3.0 N) and VP group (12.3 ± 1.0 N) did not differ significantly in terms of yielding force, with both achieving lower yielding forces relative to the DP + VP group and 2 K group. The DP + VP group (19.8±6.3 N/mm) achieved the highest level of stiffness, and the other three groups did not differ significantly in terms of stiffness (2 K group, 5.4 ± 1.1 N/mm; DP group, 4.0 ± 0.9 N/mm; VP group, 3.9 ± 1.9 N/mm). CONCLUSIONS The fixation method involving the combined use of dorsal and volar locked plates (DP + VP group) resulted in optimal outcomes with respect to fixing metacarpal shaft fractures with volar wedge bone defects.
Collapse
Affiliation(s)
- Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, 404, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Tsung-Yu Ho
- School of Medicine, China Medical University, Taichung, 404, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Cheng-En Hsu
- Department of Orthopaedics, Taichung Veterans General Hospital, Taichung, 407, Taiwan
- Sports Recreation and Health Management Continuing Studies-Bachelor's Degree Completion Program, Tunghai University, Taichung, 407, Taiwan
| | - Chen-Wei Yeh
- School of Medicine, China Medical University, Taichung, 404, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Yen-Nien Ting
- 3D Printing Medical Research Center, China Medical University Hospital, Taichung, 404, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan
| | - Jui-Ting Hsu
- Department of Biomedical Engineering, China Medical University, Taichung, 404, Taiwan.
- School of Dentistry, China Medical University, Taichung, 404, Taiwan.
| |
Collapse
|
2
|
Ho TY, Hsu CE, Wang WC, Ting YN, Tsai MT, Chiu YC, Hsu JT. Biomechanical study of the fixation ability of the dorsal and volar locking plate for transverse metacarpal neck fractures. Medicine (Baltimore) 2023; 102:e34981. [PMID: 37682204 PMCID: PMC10489259 DOI: 10.1097/md.0000000000034981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/07/2023] [Indexed: 09/09/2023] Open
Abstract
Metacarpal neck fracture is one of the most common types of hand fractures; the literature suggests that applying a bone plate on the dorsal side provides higher fixation strength than that provided by other fixation methods. However, bone plate fixation on the dorsal side may result in postoperative tendon adhesion. So far, no studies have investigated the fixation of metacarpal neck fractures on the volar side by using a bone plate. The objective of this study was to investigate the differences in the fixation results between bone plate fixation on the dorsal side and bone plate fixation on the volar side of the metacarpal in the case of a metacarpal neck fracture. A saw blade was used to create a transverse metacarpal neck fracture on 14 artificial metacarpal bone specimens. The specimens were divided into 2 groups depending on the fixation method: a volar locking plate (VLP) group and a dorsal locking plate (DLP) group. All specimens were subjected to a cantilever bending test on a material testing system, and a force-displacement curve was used to measure the yield force and stiffness, which served as an indicator of the fixation ability of the 2 fracture fixation methods. For the experimental results, the Mann-Whitney U test was used to compare the fixation abilities of the 2 fixation methods. In terms of yield force, the DLP group (266.9 ± 68.3 N) scored significantly higher than the VLP group (32.6 ± 2.7 N) (P < .05); expressed in terms of median, the DLP group scored 8.2 times higher than the VLP group. Similarly, in terms of stiffness, the DLP group (69.0 ± 13.4 N/mm, median ± interquartile range) scored significantly higher than the VLP group (12.9 ± 1.4 N/mm) (P < .05); expressed in terms of median, the DLP group scored 5.3 times higher than the VLP group. The fixation strength of volar bone plates is only about one-third of that of dorsal bone plates.
Collapse
Affiliation(s)
- Tsung-Yu Ho
- School of Medicine, China Medical University, Taichung, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan
| | - Cheng-En Hsu
- Department of Orthopaedics, Taichung Veterans General Hospital, Taichung, Taiwan
- Sports Recreation and Health Management Continuing Studies-Bachelor’s Degree Completion Program, Tunghai University, Taichung, Taiwan
| | - Wei-Chih Wang
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan
- Department of Orthopedic Surgery, China Medical University Hsinchu Hospital, Hsinchu, Taiwan
| | - Yen-Nien Ting
- 3D Printing Medical Research Center, China Medical University Hospital, Taichung, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, Taiwan
| | - Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan
| | - Jui-Ting Hsu
- Department of Biomedical Engineering, China Medical University, Taichung, Taiwan
- School of Dentistry, China Medical University, Taichung, Taiwan
| |
Collapse
|
3
|
Chiu YC, Hsu CE, Ho TY, Ting YN, Wei BH, Tsai MT, Hsu JT. Comparison of the fixation ability of headless compression screws and locking plate for metacarpal shaft transverse fracture. Medicine (Baltimore) 2021; 100:e27375. [PMID: 34596154 PMCID: PMC8483876 DOI: 10.1097/md.0000000000027375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 09/11/2021] [Indexed: 01/05/2023] Open
Abstract
Metacarpal shaft fractures are common hand fractures. Although bone plates possess strong fixation ability, they have several limitations. The use of headless compression screws for fracture repair has been reported, but their fixation ability has not been understood clearly.This study aimed to compare the fixation ability of locked plate with that of headless compression screw for metacarpal fracture repair.A total of 14 artificial metacarpal bones (Sawbones, Vashon, WA, USA) were subjected to transverse metacarpal shaft fractures and divided into 2 groups. The first group of bones was fixed using locked plates (LP group), whereas the second group was fixed using headless compression screws (HC group). A material testing machine was used to perform cantilever bending tests, whereby maximum fracture force and stiffness were measured. The fixation methods were compared by conducting a Mann-Whitney U test.The maximum fracture force of the HC group (285.6 ± 57.3 N, median + interquartile range) was significantly higher than that of the LP group (227.8 ± 37.5 N; P < .05). The median of the HC group was 25.4% greater. However, no significant difference in stiffness (P > .05) was observed between the HC (65.2 ± 24.6 N/mm) and LP (61.7 ± 19.7 N/mm) groups.Headless compression screws exhibited greater fixability than did locked plates, particularly in its resistance to maximum fracture force.
Collapse
Affiliation(s)
- Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, Taiwan
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan
| | - Cheng-En Hsu
- Department of Orthopedics, Taichung Veterans General Hospital, Taichung, Taiwan
- Sports Recreation and Health Management Continuing Studies-Bachelor's Degree Completion Program, Tunghai University, Taichung, Taiwan
| | - Tsung-Yu Ho
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan
| | - Yen-Nien Ting
- 3D Printing Medical Research Center, China Medical University Hospital, Taichung, Taiwan
| | - Bor-Han Wei
- Orthopedic Department, China Medical University Beigang Hospital, Yunlin County, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, Taiwan, ROC
| | - Jui-Ting Hsu
- School of Dentistry, College of Dentistry, China Medical University, Taichung, Taiwan
- Department of Bioinformatics and Medical Engineering, Asia University, Taichung, Taiwan
| |
Collapse
|
4
|
Chiu YC, Hsu CE, Ho TY, Ting YN, Tsai MT, Hsu JT. Effect of a figure-of-eight cerclage wire with two Kirschner wires on fixation strength for transverse metacarpal shaft fractures: an in vitro study with artificial bone. BMC Musculoskelet Disord 2021; 22:431. [PMID: 33971840 PMCID: PMC8112006 DOI: 10.1186/s12891-021-04276-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 04/16/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Metacarpal shaft fractures are a common type of hand fracture. Despite providing strong fixation strength, plate fixation has numerous shortcomings. Concerning internal fixation with Kirschner wires (K-wires), although this approach is frequently used to treat metacarpal shaft fractures, the lack of functional stability may result in fixation failure. OBJECTIVE To evaluate the effect of figure-of-eight cerclage wire on fixation for transverse metacarpal shaft fractures using two K-wires. MATERIALS AND METHODS We used a saw blade to create transverse metacarpal shaft fractures in 14 fourth-generation artificial third metacarpal bones (Sawbones, Vashon, WA, USA), which were assigned to groups undergoing fixation with two K-wires (KP) or with two K-wires and figure-of-eight cerclage wire (KP&F8). All specimens were subjected to material testing, specifically cantilever bending tests. The maximum fracture force and stiffness of the two fixation types were determined on the basis of the force-displacement data. The Mann-Whitney U test was used to compare between-group differences in maximum fracture force and stiffness. RESULTS The maximum fracture force of the KP group (median ± interquartile range = 97.30 ± 29.70 N) was significantly lower than that of the KP&F8 group (153.2 ± 69.50 N, p < 0.05; Figure 5a), with the median of the KP&F8 group exceeding that of the KP group by 57.5%. Similarly, stiffness was significantly lower in the KP group (18.14 ± 9.84 N/mm) than in the KP&F8 group (38.25 ± 23.49 N/mm; p < 0.05; Figure 5b), with the median of the KP&F8 group exceeding that of the KP group by 110.9%. CONCLUSION The incorporation of a figure-of-eight cerclage wire increased the maximum fracture force and stiffness by 57.5 and 110.9%, respectively, compared with those achieved in standard two K-wire fixation. Therefore, hand surgeons are advised to consider the proposed approach to increase fixation strength.
Collapse
Affiliation(s)
- Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, 404, Taiwan.,Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Cheng-En Hsu
- Department of Orthopaedics, Taichung Veterans General Hospital, Taichung, 407, Taiwan.,Sports Recreation and Health Management Continuing Studies-Bachelor's Degree Completion Program, Tunghai University, Taichung, 407, Taiwan
| | - Tsung-Yu Ho
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Yen-Nien Ting
- 3D Printing Medical Research Center, China Medical University Hospital, Taichung, 404, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan, ROC
| | - Jui-Ting Hsu
- School of Dentistry, College of Dentistry, China Medical University, Taichung, 404, Taiwan. .,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan.
| |
Collapse
|
5
|
Chiu YC, Ho TY, Ting YN, Tsai MT, Huang HL, Hsu CE, Hsu JT. Effect of oblique headless compression screw fixation for metacarpal shaft fracture: a biomechanical in vitro study. BMC Musculoskelet Disord 2021; 22:146. [PMID: 33546670 PMCID: PMC7866681 DOI: 10.1186/s12891-020-03939-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/22/2020] [Indexed: 11/25/2022] Open
Abstract
Background Metacarpal shaft fracture is a common fracture in hand trauma injuries. Surgical intervention is indicated when fractures are unstable or involve considerable displacement. Current fixation options include Kirschner wire, bone plates, and intramedullary headless screws. Common complications include joint stiffness, tendon irritation, implant loosening, and cartilage damage. Objective We propose a modified fixation approach using headless compression screws to treat transverse or short-oblique metacarpal shaft fracture. Materials and methods We used a saw blade to model transverse metacarpal neck fractures in 28 fresh porcine metacarpals, which were then treated with the following four fixation methods: (1) locked plate with five locked bicortical screws (LP group), (2) regular plate with five bicortical screws (RP group), (3) two Kirschner wires (K group), and (4) a headless compression screw (HC group). In the HC group, we proposed a novel fixation model in which the screw trajectory was oblique to the long axis of the metacarpal bone. The entry point of the screw was in the dorsum of the metacarpal neck, and the exit point was in the volar cortex of the supracondylar region; thus, the screw did not damage the articular cartilage. The specimens were tested using a modified three-point bending test on a material testing system. The maximum fracture forces and stiffness values of the four fixation types were determined by observing the force–displacement curves. Finally, the Kruskal–Wallis test was adopted to process the data, and the exact Wilcoxon rank sum test with Bonferroni adjustment was performed to conduct paired comparisons among the groups. Results The maximum fracture forces (median ± interquartile range [IQR]) of the LP, RP, HC, and K groups were 173.0 ± 81.0, 156.0 ± 117.9, 60.4 ± 21.0, and 51.8 ± 60.7 N, respectively. In addition, the stiffness values (median ± IQR) of the LP, HC, RP, and K groups were 29.6 ± 3.0, 23.1 ± 5.2, 22.6 ± 2.8, and 14.7 ± 5.6 N/mm, respectively. Conclusion Headless compression screw fixation provides fixation strength similar to locked and regular plates for the fixation of metacarpal shaft fractures. The headless screw was inserted obliquely to the long axis of the metacarpal bone. The entry point of the screw was in the dorsum of the metacarpal neck, and the exit point was in the volar cortex of the supracondylar region; therefore the articular cartilage iatrogenic injury can be avoidable. This modified fixation method may prevent tendon irritation and joint cartilage violation caused by plating and intramedullary headless screw fixation.
Collapse
Affiliation(s)
- Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, 404, Taiwan.,Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Tsung-Yu Ho
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan
| | - Yen-Nien Ting
- 3D Printing Medical Research Center, China Medical University Hospital, Taichung, 404, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, Taiwan, Republic of China, 433
| | - Heng-Li Huang
- School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan.,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan
| | - Cheng-En Hsu
- Department of Orthopaedics, Taichung Veterans General Hospital, No. 1650, Sec. 4 Taiwan Boulevard, Situng Dist., Taichung City, 407, Taiwan (Republic of China). .,Sports Recreation and Health Management Continuing Studies-Bachelor's Degree Completion Program, Tunghai University, Taichung, 407, Taiwan.
| | - Jui-Ting Hsu
- School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan. .,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan.
| |
Collapse
|
6
|
Chiu YC, Tsai MT, Hsu CE, Hsu HC, Huang HL, Hsu JT. New fixation approach for transverse metacarpal neck fracture: a biomechanical study. J Orthop Surg Res 2018; 13:183. [PMID: 30045774 PMCID: PMC6060459 DOI: 10.1186/s13018-018-0890-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 07/12/2018] [Indexed: 11/18/2022] Open
Abstract
Background Fifth metacarpal neck fracture, also known as boxer’s fracture, is the most common metacarpal fracture. Percutaneous Kirschner-wire (K-wire) pinning has been shown to produce favorable clinical results. However, the fixation power of K-wires is a major concern. Plate fixation is also a surgical option, but it has the disadvantages of tendon adhesion, requirement of secondary surgery for removal of the implant, and postoperative joint stiffness. A fixation method that causes little soft tissue damage and provides high biomechanical stability is required for patients with fifth metacarpal neck fracture for whom surgical intervention is indicated. The present study proposed fixation using K-wires and a cerclage wire to treat fifth metacarpal neck fracture. The fixation power of this new method was compared with that of K-wires alone and plates. Methods We used a saw blade to create transverse metacarpal neck fractures in 16 artificial metacarpal bone specimens, which were then treated with four types of fixation as follows: (1) locking plate with five locking bicortical screws (LP group), (2) regular plate with five bicortical screws (RP group), (3) two K-wires (K group), and (4) two K-wires and a figure-of-eight cerclage wire (KW group). The specimens were tested by using cantilever bending testing on a material testing system. The stiffness of the four fixation types was determined by observing force–displacement curves. Finally, the Kruskal–Wallis test was adopted to process the data, and the Mann–Whitney exact test was performed to conduct paired comparison between the fixation types. Results The fixation strength levels of the four fixation approaches for treating fifth metacarpal neck fracture were ranked in a descending order of LP group (24.6 ± 5.1 N/mm, median ± interquartile range) > RP group (22.2 ± 5.8 N/mm) ≅ KW group (20.1 ± 3.2 N/mm) > K group (16.9 ± 3.0 N/mm). Conclusion The fixation strength of two K-wires was significantly higher when reinforcement was provided using a figure-of-eight cerclage wire. The strength of the proposed approach is similar to that of a regular plate with five bicortical screws but weaker than that of a locking plate with the same amount of bicortical screws. Cerclage wire-integrated K-wires can be an alternative method that avoids the excessive soft tissue dissection required for plating in open reduction internal fixation for fifth metacarpal neck fracture.
Collapse
Affiliation(s)
- Yung-Cheng Chiu
- School of Medicine, China Medical University, Taichung, 404, Taiwan.,Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan, Republic of China
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan
| | - Cheng-En Hsu
- Department of Orthopaedics, Taichung Veterans General Hospital, Taichung, 407, Taiwan.,Sports Recreation and Health Management Continuing Studies-Bachelor's Degree Completion Program, Tunghai University, Taichung, 407, Taiwan
| | - Horng-Chaung Hsu
- School of Medicine, China Medical University, Taichung, 404, Taiwan.,Department of Orthopedic Surgery, China Medical University Hospital, Taichung, 404, Taiwan, Republic of China
| | - Heng-Li Huang
- School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan.,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan
| | - Jui-Ting Hsu
- School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan. .,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan.
| |
Collapse
|
7
|
Abstract
There are multiple surgical techniques to stabilize the bone in digital replantation. Various criteria need to be considered when choosing appropriate bony fixation including operative time, ease of exposure, stability, limitation of the area of dissection, and reproducibility. We describe our technique using internal fixation with a low-profile plate on the palmar aspect of the proximal or middle phalanx during replantation of a digit. This technique allows coverage of the plate with no risk of compromising the dorsal venous anastomosis. In our experience, using this technique we have observed no complications including no secondary displacement of the fragments or extensor tendon rupture and no incidence of infection. In addition, this technique allows adequate bony fixation to enable an early active range of motion rehabilitation program.
Collapse
|
8
|
Unicortical PEEK inset locking fixation for metacarpal fractures: a biomechanical study. EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY 2015; 24:1415-20. [PMID: 24121825 DOI: 10.1007/s00590-013-1322-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 09/24/2013] [Indexed: 12/21/2022]
Abstract
PURPOSE There are numerous constructs employed in the treatment of metacarpal fractures with varying degrees of success. While plate fixation commonly involves dorsal application of a bicortical non-locking plate, there has been recent exploration of other fixation options including unicortical locked plating. The purpose of this study was to evaluate the biomechanical integrity of a polyetheretherketone (PEEK) inset locking plate and, in doing so, compare it to standard plate fixation (utilizing a clinically proven bicortical non-locking titanium plate) in a simulated porcine metacarpal fracture model. METHODS Reproducible mid-shaft fractures were created in porcine second metacarpals. The fractured specimens were reduced and plated with either a bicortical non-locking plate or a unicortical locking plate with a PEEK locking design. Constructs were then loaded to failure in the same fashion as performed to create the fracture. Peak load was measured as the apex on the load-to-failure deflection curve. Stiffness was calculated as the linear slope on the load-to-failure deflection curve. Data were analyzed via Student's t test. RESULTS Unicortical locking constructs failed at 344 ± 119 N, while bicortical non-locking constructs were found to fail at 277 ± 101 N (p = 0.19). The unicortical locking constructs demonstrated a stiffness of 80 ± 36 N/mm compared with the bicortical non-locking constructs (69 ± 36 N/mm) although again the difference was not found to be statistically different (p = 0.49). CONCLUSION Based on this study, a locked plating construct using a polymer mechanism provides an interesting new locking fixation method for small bone fractures and with our limited number of specimens tested, provided at least a similar strength and rigidity profile in comparison with bicortical fixation in the treatment of metacarpal fractures.
Collapse
|
9
|
Biomechanical analysis of the efficacy of locking plates during cyclic loading in metacarpal fractures. ScientificWorldJournal 2014; 2014:648787. [PMID: 24757429 PMCID: PMC3976824 DOI: 10.1155/2014/648787] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Accepted: 02/19/2014] [Indexed: 11/17/2022] Open
Abstract
PURPOSE To analyse the biomechanical characteristics of locking plates under cyclic loading compared to a nonlocking plate in a diaphyseal metacarpal fracture. METHODS Oblique diaphyseal shaft fractures in porcine metacarpal bones were created in a biomechanical fracture model. An anatomical reduction and stabilization with a nonlocking and a comparable locking plate in mono- or bicortical screw fixation followed. Under cyclic loading, the displacement, and in subsequent load-to-failure tests, the maximum load and stiffness were measured. RESULTS For the monocortical screw fixation of the locking plate, a similar displacement, maximum load, and stiffness could be demonstrated compared to the bicortical screw fixation of the nonlocking plate. CONCLUSIONS Locking plates in monocortical configuration may function as a useful alternative to the currently common treatment with bicortical fixations. Thereby, irritation of the flexor tendons would be avoided without compromising the stability, thus enabling the necessary early functional rehabilitation.
Collapse
|
10
|
Higher stability with locking plates in hand surgery? Biomechanical investigation of the TriLock system in a fracture model. INTERNATIONAL ORTHOPAEDICS 2012; 36:1641-6. [PMID: 22426933 DOI: 10.1007/s00264-012-1524-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 02/28/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE The aim of this study was to determine the biomechanical characteristics of locking plates with the TriLock system with different design and screw settings compared to a non-locking plate in a diaphyseal metacarpal fracture. METHODS Oblique diaphyseal shaft fractures in porcine metacarpal bones were created in a biomechanical fracture model. After reduction they were fixed with three different locking plates with the TriLock interlocking mechanism or a non-locking linear plate in mono- or bicortical screw fixations. In load to failure tests the maximum load and stiffness were measured. RESULTS For linear plates, the maximum load was higher for the non-locking plate compared with the locking plate. The maximum load could be increased for the locking plates using a double-row design and a higher screw number. No differences were found for the stiffness between all groups. In contrast to the non-locking plate, the mode of failure of the locking plates in many cases (86 %) was a loss of the interlocking mechanism. CONCLUSIONS The results suggest that the locking plates with the TriLock system achieve no higher stability compared to a non-locking plate in load to failure tests. Adaptions to increase the stability of the interlocking mechanism are desirable.
Collapse
|