Cortical Screw Post Femoral Fixation Using Whipstitches, Fabric Loop, or Endobutton

SummaryThe purpose of the study was to determine and to compare the in vitro pullout strength of 5.5 mm cortical versus 6.5 mm cancellous bone screws inserted in the diaphysis and metaphysis of foal third metacarpal (MCIII) bones in threaded 4.5 mm cortical bone screw insertion holes that were then overdrilled with a 4.5 mm drill bit. This information is relevant to the selection of a replacement screw if a 4.5 mm cortical screw is stripped during orthopaedic surgery. In vitro pullout tests were performed in two independent cadaver studies, each consisting of 12 foal MCIII bones. Two 4.5 mm cortical screws were placed either in the mid-diaphysis (study 1) or distal metaphysis (study 2) of MCIII bones. The holes were then overdrilled with a 4.5 mm bit and had either a 5.5 mm cortical or a 6.5 mm cancellous screw inserted; screw pullout tests were performed at a rate of 0.04 mm/s until screw or bone failure occurred.The bone failed in all of the tests in the diaphyseal and metaphyseal bone. The holding power for 6.5 mm cancellous screws was significantly (p <0.05) greater than for 5.5 mm cortical screws in both the diaphysis and metaphysis. There was not any difference in the holding power of screws in either the diaphysis or the metaphysis between proximal and distal screw holes.If a 4.5 mm cortical bone screw strips in MCIII diaphyseal or metaphyseal bone of foals, a 6.5 mm cancellous screw would provide greater holding power than a 5.5 mm cortical screw.In order to provide information regarding selection of a replacement screw if a 4.5 mm cortical screw is stripped, the in vitro pullout strength was determined for 5.5 mm cortical and 6.5 mm cancellous screws inserted in third metacarpal diaphyseal and metaphyseal bone of foals in which threaded 4.5 mm cortical bone screw insertion holes had been overdrilled with a 4.5 mm bit. The holding power of the 6.5 mm cancellous screw was significantly greater than the 5.5 mm cortical screw in both the diaphysis and metaphysis of foal third metacarpal bone. Thus, it appears that if a 4.5 mm cortical screw is stripped during orthopaedic surgery in foals, a 6.5 mm cancellous screw would provide superior holding power.

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Holding Power of Orthopaedic Screws in Bovine Femoral Heads

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633115 ◽

1993 ◽

Vol 06 (03) ◽

pp. 160-162 ◽

Cited By ~ 2

Author(s):

M. J. Ulm ◽

D. G. Wilson

Keyword(s):

Femoral Head ◽

Cannulated Screws ◽

Cancellous Screw ◽

Holding Power ◽

Cortical Screw ◽

Femoral Heads ◽

Cancellous Screws ◽

Physeal Fractures

SummaryFemoral capital physeal fractures have been successfully repaired using 7.0 mm cannulated screws. The holding power of 7.0 mm cannulated screws was compared to the holding power of 5.5 mm cortical screws and 6.5 mm cancellous screws using paired bovine femoral heads. The 7.0 mm cannulated screw’s holding power was superior to the 6.5 mm cancellous screw and similar to that of the 5.5 mm cortical screw.When placed in the bovine femoral head, 7.0 mm cannulated screws have holding power greater than 6.5 mm cancellous screws and similar to 5.5 mm cortical screws.

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Basal Implant: A Remedy to Restore Resorbed Alveolar Ridges

Dental Journal of Advance Studies ◽

10.1055/s-0041-1731102 ◽

2021 ◽

Author(s):

Prakhar Thakur ◽

Tarun Kalra ◽

Manjit Kumar ◽

Ajay Bansal ◽

Shefali Malik

Keyword(s):

Cortical Bone ◽

Immediate Loading ◽

Osseous Tissue ◽

Alveolar Process ◽

Implant Stability ◽

Implant Placement ◽

Cortical Screw ◽

Functional Differences ◽

Basal Bone ◽

Cortical Implants

AbstractThe conventional crestal implants are used only when there is adequate jawbone height and width. Results of conventional implants are good in patients with healthy bone at the time of treatment, but prognosis gets deteriorated when surgical augmentation of bone is included with implant placement. These augmentation procedures have surgical risks and are costlier to the patients. Patients with atrophied jawbones are given no treatment, until crestal implants are seen as the last option. In this article, the indications for basal implants and functional differences between basal implants and crestal implants have been discussed.Patients with extreme jawbone atrophy do not benefit from crestal implants. The basal bone is the (cortical) osseous tissue of the mandible and maxilla, and lies below the alveolar process, which has a relatively strong and no resorbing framework.Basal osseointegrated and basal cortical screw (BCS) are two types of implants designed to take anchorage from the cortical bone of the jaw. BCS implants have long shafts and can be placed immediately in the socket after extraction and provided with immediate loading within 72 hours of implant placement. Basal implants are also called bicortical or cortical implants as they utilize the cortical portion of the jawbones for anchorage and implant stability. The basal bone has better quality and quantity of cortical bone for retention of these unique and highly advanced implants. The other names for these implants are lateral implants or disk implants.

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Interference Screw Versus Suture Anchors for Femoral Fixation in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Study

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121989282 ◽

2021 ◽

Vol 9 (3) ◽

pp. 232596712198928

Author(s):

Heath P. Gould ◽

Nicholas R. Delaney ◽

Brent G. Parks ◽

Roshan T. Melvani ◽

Richard Y. Hinton

Keyword(s):

Medial Patellofemoral Ligament ◽

Interference Screw ◽

Biomechanical Study ◽

Graft Fixation ◽

Mpfl Reconstruction ◽

Suture Anchors ◽

Femoral Fixation ◽

Significant Difference ◽

Load To Failure ◽

The Mean

Background: Femoral-sided graft fixation in medial patellofemoral ligament (MPFL) reconstruction is commonly performed using an interference screw (IS). However, the IS method is associated with several clinical disadvantages that may be ameliorated by the use of suture anchors (SAs) for femoral fixation. Purpose: To compare the load to failure and stiffness of SAs versus an IS for the femoral fixation of a semitendinosus autograft in MPFL reconstruction. Study Design: Controlled laboratory study. Methods: Based on a priori power analysis, a total of 6 matched pairs of cadaveric knees were included. Specimens in each pair were randomly assigned to receive either SA or IS fixation. After an appropriate reconstruction procedure, the looped end of the MPFL graft was pulled laterally at a rate of 6 mm/s until construct failure. The best-fit slope of the load-displacement curve was then used to calculate the stiffness (N/mm) in a post hoc fashion. A paired t test was used to compare the mean load to failure and the mean stiffness between groups. Results: No significant difference in load to failure was observed between the IS and the SA fixation groups (294.0 ± 61.1 vs 250.0 ± 55.9; P = .352), although the mean stiffness was significantly higher in IS specimens (34.5 ± 9.6 vs 14.7 ± 1.2; P = .004). All IS reconstructions failed by graft pullout from the femoral tunnel, whereas 5 of the 6 SA reconstructions failed by anchor pullout. Conclusion: In this biomechanical study using a cadaveric model of MPFL reconstruction, SA femoral fixation was not significantly different from IS fixation in terms of load to failure. The mean load-to-failure values for both reconstruction techniques were greater than the literature-reported values for the native MPFL. Clinical Relevance: These results suggest that SAs are a biomechanically viable alternative for femoral-sided graft fixation in MPFL reconstruction.

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