Helical 6-Strand Cruciate Tenorrhaphy: Description of a New Technique and Biomechanical Comparative Analysis With 2 Standard Techniques

Background: Multiple flexor tendon repair techniques have been developed over the last years. Despite all this, there is no standard technique that has proven to be superior to others, leading to great variability in the use of techniques in surgical practice. We describe a novel tendon repair technique and compare its biomechanical characteristics with 2 conventional techniques. Methods: Comparative experimental biomechanical study in ex vivo animal models. In all, 66 deep flexor tendons of the pig's front legs were taken and it's repair was performed by 1 of 3 techniques (helical 6-strand cruciate tendon repair, Adelaide tendon repair, or modified Kessler). These repairs were subjected to biomechanical study, measuring, and registering the ultimate tensile strength, load to 2-mm gap force, and stiffness. Results: The helical 6-strand cruciate tenorrhaphy compared with the Adelaide and modified Kessler techniques carries statistically significant greater ultimate tensile strength before failure (65.5, 46, and 36 N, respectively, P < .001). It also required a greater load to 2-mm gap force and is less stiff, allowing greater strain before failure. This technique does not generate significant changes in the dimensions of the tendons compared to the others, and there was no significant difference in the strength of repair between surgeons. Conclusions: The helical 6-strand cruciate tenorrhaphy is a novel technique, useful for the repair of flexor tendons in the hand that holds up the necessary forces to initiate early mobilization in the postoperative period and has better biomechanical properties than 2 standard techniques.

Malocclusion Management Following Mandibular Reconstruction With Free Fibula Flaps

Study Design

Free fibula flaps are nowadays the gold standard for the surgical reconstruction on large mandibular defects. Malocclusion is an important complication of this type of reconstruction and many of these patients end up requiring subsequent orthognathic corrective surgery. This is a descriptive retrospective case series study.

Objective

To describe the demographic data, operative techniques, corrective methods and postoperative results in the management of malocclusion following mandibular reconstruction with free fibula flap.

Methods

This case series study included patients who underwent free fibula flap mandibular reconstructions and who that subsequently developed malocclusion requiring orthognathic corrective surgery, from June 2010 to December 2019. Panoramic X-rays, cephalometries and/or 3-D facial reconstruction CT scans were used for surgical planning to create surgical cutting guides, templates and occlusal splints in all the patients that underwent corrective orthognathic surgery.

Results

There were 46 patients who underwent a free fibula flap mandibular and maxillary reconstruction at San Jose Hospital between June 2010 and December 2019 of these, 5 patients (10.9%) developed postoperative malocclusion. One case from another institution was added to this study for a total of 6 patients with malocclusion following mandibular reconstruction surgery with a fibula free flap. During the orthognathic surgery, vertical osteotomies were performed in 3 patients and bilateral sagittal split osteotomies were necessary in 2 patients and L-shape in 1 patient. Osteogenic distraction was performed in 3 patients as part of their orthognathic treatment. The fixation methods were based in miniplates for 3 of the patients and lag screws for the remaining 3 patients. With this approach, all patients had an adequate occlusion correction with a 100% consolidation at their 6-month follow up.

Conclusion

Malocclusion is a significant complication following mandibular reconstruction surgery that must be identified and managed. In severe cases, it requires corrective orthognathic surgery in severe cases. We have developed a protocol to avoid pitfalls during the primary reconstruction and in case an orthognathic surgery is required for malocclusion correction, preoperative planning with cutting guides and occlusal splints should be assessed, to guarantee favorable results through a reproducible technique.