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INTRODUCTION: The treatment of Lisfranc injuries continues to evolve with time. The purpose of this study was to report early outcomes of patients with Lisfranc ligamentous injuries treated with the Arthrex InternalBrace, which has benefits to other previously described techniques. MATERIALS AND METHODS: We retrospectively identified 15 adult patients with Lisfranc injuries that were treated via open reduction internal fixation with the Arthrex InternalBrace (Naples, Fl). These patients were identified at two separate United States institutions between 2019 and 2022. Demographic data, mechanism of injury, and concomitant foot injuries were recorded. Outcomes were assessed by return-to-work or sport and time to weight-bearing. Secondary complications or revision surgeries were noted. RESULTS: The mean patient age was 35 years. Eight patients had isolated Lisfranc ligamentous injuries and seven had additional intercuneiform instability, which required a supplemental limb of the fixation device. The most common mechanism of injury was a cutting/pivoting maneuver (n = 5) followed by fall (n = 4). The mean radiographic follow-up time was 7.3 months. The average time to weight-bearing as tolerated was 6.6 weeks (± 2.2). The average time to return-to-work/sport as tolerated was 14.1 weeks (± 3.6). Only two minor complications were noted at follow-up but no major complications or revision surgeries occurred. CONCLUSIONS: The outcomes of this case series suggest that the Arthrex InternalBrace is a viable option when performing open reduction and internal fixation of Lisfranc ligamentous injuries. Future prospective studies are needed to directly compare this device with alternative fixation methods.

Abstract Background The biomechanical environment created by suture‐button fixation Latarjet is conducive to the healing and shaping of the transplanted coracoid, but its mechanism remains unclear. The latest research has found that the absence of stem cell chemokine (CXCL12) impeded bone regeneration in Sonic Hedgehog (SHH)‐deficient animals. However, whether the biomechanical environment affects SHH and CXCL12 function has not been studied. Methods Rat fracture models were constructed to simulate stress environments under non‐load‐bearing and load‐bearing conditions. The fracture healing and shaping, as well as the expression levels of SHH and CXCL12, were assessed through gross viewing, micro‐computed tomography (micro‐CT), and histochemical staining. Results Under flexible fixation, the relative bone volume (BV/TV) of rats exposed to the load‐bearing stress environment was significantly higher than that of rats under a non‐load‐bearing stress environment (p ≤ 0.05). Adverse bone shaping was not observed in rats subjected to flexible fixation. The levels of SHH and CXCL12 in load‐bearing rats exhibited significant elevation (p ≤ 0.05). Under a load‐bearing stress environment, no significant difference was observed in the BV/TV between the flexible fixation group and the rigid fixation group (p ≥ 0.05), but there was excessive hyperplasia of the fracture callus in the rigid fixation group. The levels of SHH and CXCL12 in rats subjected to rigid fixation were significantly elevated (p ≤ 0.05). Conclusions Flexible fixation and load‐bearing stress environment may contribute to bone healing and shaping by influencing the levels of SHH and CXCL12, suggested that this mechanism may be relevant to the healing and shaping of the transplanted coracoid after suture‐button fixation Latarjet.

Background: Lisfranc injuries are often treated with open reduction and internal fixation using rigid fixation techniques. The use of flexible fixation to stabilize the Lisfranc joint is a newer technique. The purpose of this cadaveric study is to compare the amount of diastasis at the Lisfranc interval under diminished physiologic loads when treated with a knotless suture tape construct and a solid screw. Methods: Ten cadavers (20 feet) had native motion at the intact Lisfranc interval assessed at multiple increasing loads (69, 138, and 207 N). The Lisfranc ligamentous complex was then disrupted, and testing repeated to evaluate the amount of diastasis. Randomization was performed to determine the type of fixation for each cadaver: solid screw or knotless suture tape construct. Once fixation was completed, specimens were cyclically loaded for 10 000 cycles at loads, and diastasis was quantified after each load cycle to compare the interventions. Diastasis was measured using motion tracking cameras and retroreflective marker sets. A non-inferiority statistical analysis was performed. Results: Diastasis mean values were confirmed to be >2 mm for all load bearing conditions in the injury model. Posttreatment, diastasis was significantly reduced when compared to the sectioned conditions (P <.01) for both treatment options. Non-inferiority analyses showed that the knotless suture tape construct did not perform inferior to screw fixation for diastasis at the Lisfranc interval at any of the compared load states. Conclusion: Under the loads tested, there is no significant difference in diastasis at the Lisfranc interval when treating ligamentous Lisfranc injuries with a knotless suture tape construct or solid screws. Both reduced diastasis from the injured state and were not different from the intact state. Clinical Relevance: In this cadaveric model with ligamentous Lisfranc injury, diastasis of a knotless suture tape construct is compared to solid screw fixation as tested. [ABSTRACT FROM AUTHOR]

Ankle fractures with syndesmosis disruption present a challenge for foot and ankle surgeons. After open reduction internal fixation (ORIF), conventional postoperative treatment requires a period of immobilization and non-weightbearing, which if prolonged, can be detrimental to patients. The purpose of this case series is to present outcomes of early weightbearing after ankle fracture ORIF requiring syndesmosis stabilization using a dynamic fixation device. Thirty consecutive patients from August 2019 to July 2021 were included. Medical records and radiographs were reviewed to determine patient and surgical characteristics, postoperative complications, and reduction maintenance. Surgical treatment consisted of ORIF of malleolar fractures and stabilization of the syndesmosis with a Tightrope® XP (Arthrex Inc., Naples, FL). The mean age was 49 years. Mean BMI was 28.8. There were 24 supination-external rotation and 6 pronation-external rotation injuries. Twenty-six patients had syndesmosis fixation with a single implant, and 4 patients had syndesmosis fixation with two implants. The average time to weightbearing in a walking boot was 9.7 days. Average follow up was 13 months. One patient developed early postoperative saphenous neuritis, which resolved with conservative measures. There were no infections, malunions or nonunions, and all patients maintained fracture and syndesmosis reduction. In conclusion, the Tightrope® XP provides a safe and effective method for treatment of ankle fractures with syndesmosis disruption and supports early weightbearing after ORIF in an active healthy population. The results of this study are comparable to prior studies and show there is a low risk of complication and need for routine removal of implants.

Purpose: Fibular mobility after suture button stabilization (SBS) of inferior tibiofibular joint (syndesmosis) injuries has been described. This effect is called the "flexible nature of fixation (FNF)." In this study, we aimed to quantify FNF in syndesmotic stabilization.Methods: Postoperative bilateral computed tomography (CT) of ankle fractures with syndesmosis stabilization by SBS or syndesmotic screw (SYS) was retrospectively analyzed. The transverse offset (TO) and vertical offset (VO) were defined by evaluating the drill channels. The reduction outcome was evaluated by the side-to-side difference between the clear space and the anterior tibiofibular distance (antTFD). The calculated anterior tibiofibular distance (cal-antTFD) was calculated by subtracting the TO from the validated antTFD. Subsequently, a reevaluation of the reduction outcomes after SYS or SBS stabilization was performed using cal-antTFD.Results: Sixty patients (44 with SBS and 16 with SYS stabilization) were analyzed. The intra-rater and inter-rater reliabilities for TO and VO were excellent (α > 0.92). SYS stabilization showed lower mean TO (- 0.02 mm; SD 0.14) and VO (0.11 mm; SD, 0.29 mm) than SBS stabilization (TO 1.16 mm, SD 1.4 mm; VO 0.2 mm, SD 0.8 mm; p = 0.001). The rate of malreduction according to cal-antTFD was higher than that of antFTD (p = 0.033).Conclusion: The presented method, which evaluates the position of the tibial to the fibular drill channel, allowed the quantification of the "FNF." The often described difference in the dynamic stabilization of SBS compared to the rigid stabilization by SYS could be objectified. Considering cal-antTFD illustrates that FNF potentially reduces the rate of malreduction in SBS stabilization. [ABSTRACT FROM AUTHOR]

Abstract Background Purely ligamentous Lisfranc injuries are mainly caused by low energy damage and often require surgical treatment. There are several operative techniques for rigid fixation to solve this problem clinically. This study evaluated the effect of using the Tightrope system to reconstruct the Lisfranc ligament for elastic fixation. Methods We retrospectively analyzed 11 cases with purely ligamentous Lisfranc injuries treated with the Tightrope system from 2016 to 2019, including 8 male and 3 female. X-ray was performed regularly after operation to measure the distance between the first and second metatarsal joint and the visual analogue scale (VAS) score was used to evaluate pain relief. American orthopedic foot & ankle society (AOFAS) and Maryland foot score were recorded at the last follow-up. Results The average follow-up time was 20.5 months (range, 17–24). There was statistically significant difference in the distance between the first and second metatarsal joint and VAS score at 3 months, 6 months, and the last follow-up when compared with preoperative values (P

Flexible fixation (FF) has allowed treatment of isolated ligamentous Lisfranc injuries while preserving joint motion. We hypothesize that patient-reported outcome measures (PROMs), complications, and return-to-activity rates will be similar between patients undergoing FF versus those undergoing open reduction internal fixation (ORIF) or primary arthrodesis (PA). Databases included PubMed, OVID Medline, Embase, SCOPUS, Cochrane Central Register of Clinical Trials, and clinicaltrials.gov from their inception to 5/13/2024. Search terms focused on treatment of Lisfranc injuries with FF, ORIF, or PA. Only English studies were included. Studies were included if the Lisfranc injury was purely ligamentous and had PROM scores. Quality, validity, and comparability were assessed using MINORS and GRADE criteria. Meta-analysis was conducted using pooled statistics. Cohen's d and odds ratios (OR) determined effect sizes. Twenty-five studies were included. There were 184 patients undergoing FF, 236 patients undergoing ORIF, and 80 patients undergoing PA. Postoperatively, American Orthopaedic Foot and Ankle Society (AOFAS) scores were 89.7 ± 10.0, 78.7 ± 44.2, and 87.4 ± 31.8, VAS-pain scores were 1.5 ± 1.5, 1.6 ± 3.8, and 0.3 ± 2.6, and return to activity rates (RTA) were 100 %, 63.3 %, and 78.4 %, respectively. Rates of post-traumatic arthritis were 0 %, 13.0 %, and 0 %, hardware removal were 0 %, 86.0 %, and 22.5 %, and complications were 3.8 %, 17.7 %, and 23.5 %. Meta-analysis demonstrated that FF had superiority over ORIF regarding better AOFAS scores and RTA with lower rates of post-traumatic arthritis, hardware removal, and complications (p < 0.05). Also, FF had superiority over PA with higher RTA and lower rates of hardware removal and complications. PA demonstrated better VAS-pain scores (p < 0.05). FF had satisfactory outcomes after Lisfranc injury treatment. Low-quality evidence suggested that FF had better outcomes, however, this conclusion was drawn from single-arm studies which have significant limitations. Further prospective, comparative studies should investigate this relationship. • Flexible fixation can be used for ligamentous Lisfranc injuries. • Conventional treatment includes ORIF and primary arthrodesis. • Flexible fixation appears to be equivalent to conventional treatment. [ABSTRACT FROM AUTHOR]

The Lapidus arthrodesis is a powerful procedure for the correction of hallux valgus with metatarsus primus varus. Yet, first ray instability may persist despite correction of the primary deformity with 2 crossed screw fixation. A third screw is often utilized as the additional point of fixation for noteworthy residual transverse plane motion, but it is not without potential complications. The suture and button fixation device may be an appropriate alternative to the third screw construct. This retrospective cohort study identified clinical / radiographic outcomes and complication rates following a third point of fixation with either a screw or suture and button fixation device in patients undergoing a modified Lapidus arthrodesis. One surgeon performed all of the Lapidus procedure with a third screw while the other surgeon performed all with a suture and button fixation device. Of 136 consecutive patients who underwent a modified Lapidus arthrodesis, 83 (61%) patients required a third point of fixation for satisfactory stabilization of the first ray. Surgical technique was similar between the 2 surgeons; however, one utilized the suture and button fixation device method (n = 36), while the other used a third screw for fixation (n = 47). Many of the clinical outcomes, radiographic results, and the union rate were similar between the 2 methods. Nineteen (40%) complications occurred in the third screw group compared to 6 (17%) in the suture and button fixation device group. However, the third screw group demonstrated 100% maintenance of deformity correction at 1 year versus 95% in the suture and button fixation device group. Although fixation with a suture and button fixation device was associated with fewer complications, a larger study is necessary to determine if these variations are statistically significant. [ABSTRACT FROM AUTHOR]

Background: Purely ligamentous Lisfranc injuries are mainly caused by low energy damage and often require surgical treatment. There are several operative techniques for rigid fixation to solve this problem clinically. This study evaluated the effect of using the Tightrope system to reconstruct the Lisfranc ligament for elastic fixation.Methods: We retrospectively analyzed 11 cases with purely ligamentous Lisfranc injuries treated with the Tightrope system from 2016 to 2019, including 8 male and 3 female. X-ray was performed regularly after operation to measure the distance between the first and second metatarsal joint and the visual analogue scale (VAS) score was used to evaluate pain relief. American orthopedic foot & ankle society (AOFAS) and Maryland foot score were recorded at the last follow-up.Results: The average follow-up time was 20.5 months (range, 17-24). There was statistically significant difference in the distance between the first and second metatarsal joint and VAS score at 3 months, 6 months, and the last follow-up when compared with preoperative values (P < 0.05).Mean of postoperative AOFAS mid-foot scale and Maryland foot score were 92.4 ± 4.3, 94.1 ± 3.5, respectively. The Tightrope system was not removed and the foot obtained better biomechanical stability. No complications occurred during the operation.Conclusion: Tightrope system in the treatment of purely ligamentous Lisfranc injuries can stabilize the tarsometatarsal joint and achieve satisfactory effect. [ABSTRACT FROM AUTHOR]

Osteogenic glue that reproduces the natural bone composition represents the final frontier of orthopedic adhesives with the potential to revolutionize surgical strategies against comminuted fractures. However, it is difficult to achieve an all‐in‐one formula, which could provide flexible and reliable adhesiveness while avoiding interfering with or even promoting the healing of glued fractures. Herein, an osteogenic glue characterized by inorganic‐in‐organic integration between amine‐modified mesoporous bioactive glass nanoparticles (AMBGN) and bioadhesive gelatin‐dextran network (GelDex) is introduced as an all‐in‐one tool to flexibly adhere and splice bone fragments and subsequently guide fracture healing during degradation. Relying on such integration, a 4‐fold improvement in cohesiveness is presented, followed by a nearly 5‐fold enhancement in adhesive strength in ex vivo porcine bone samples. The reversible and re‐adjustable adhesiveness also enables glue to effectively splice intricate fragments from highly comminuted fractures in the rabbit radius in an in vivo environment. Moreover, well‐preserved organic–inorganic integrity during degradation of the glue guides sustained interfacial osteogenesis and achieve satisfying healing outcomes in glued fractures, as observed by the 2‐fold improvement in biomechanical and radiological performance compared with commercially available cyanoacrylate adhesives. The current findings propose an all‐in‐one solution for the fixation of bone fragments during surgery. [ABSTRACT FROM AUTHOR]

Ankle fractures are common injuries. If an ankle fracture is combined with tibiofibular syndesmosis separation, then tibiofibular transfixation should be used to stabilize the syndesmosis; in such cases, flexible (suture-button) fixation is an option. We surgically treated a male patient's unstable ankle fracture with internal fixation devices, including a suture-button fixator, and observed the development of a flexor hallucis longus checkrein deformity in the postoperative period. The aim of this report is to describe this rare postoperative complication associated with the use of suture-button transfixation of the tibiofibular syndesmosis. [ABSTRACT FROM AUTHOR]

Background: The effect of syndesmotic fixation on restoration of pressure mechanics in the setting of a syndesmotic injury is largely unknown. The purpose of this study is to examine the contact mechanics of the tibiotalar joint following syndesmosis fixation with screws versus a flexible fixation device for complete syndesmotic injury.Methods: Six matched pairs of cadaveric below knee specimens were dissected and motion capture trackers were fixed to the tibia, fibula, and talus and a pressure sensor was placed in the tibiotalar joint. Each specimen was first tested intact with axial compressive load followed by external rotation while maintaining axial compression. Next, syndesmotic ligaments were sectioned and randomly assigned to repair with either two TightRopes® or two 3.5 mm cortical screws and the protocol was repeated. Mean contact pressure, peak pressure, reduction in contact area, translation of the center of pressure, and relative talar and fibular motion were calculated. Specimens were then cyclically loaded in external rotation and surviving specimens were loaded in external rotation to failure.Results: No differences in pressure measurements were observed between the intact and instrumented states during axial load. Mean contact presure relative to intact testing was increased in the screw group at 5 Nm and 7.5 Nm torque. Likewise, peak pressure was increased in the TightRope group at 7.5 Nm torque. There was no change in center of pressure in the TightRope group at any threshold; however, at every threshold tested there was significant medial and anterior translation in the screw group relative to the intact state.Conclusion: Either screws or TightRope fixation is adequate with AL alone. With lower amounts of torque, the TightRope group appears to have contact and pressure mechanics that more closely match native mechanics. [ABSTRACT FROM AUTHOR]

Lisfranc injuries require anatomic reduction and stabilization of the tarsometatarsal joints. We describe a novel technique that provides flexible fixation that is simple, cost-effective and that may offer certain advantages over more traditional techniques. [ABSTRACT FROM AUTHOR]

Implant loosening is frequently detected after fixation of open book injuries. Though many authors do not see this as a complication, it is often the reason for hardware removal or reinstrumentation in the case of remaining instability. We hypothesized that the flexibility of the implant has an influence on loosening and thus on failure of the construct.Methods We used 6 fresh-frozen pelvic specimens and tested them with our recently introduced test setup for two-leg alternate loading. We subjected them to a non-destructive quasi-static test in the intact condition followed by a non-destructive cyclic test under axial sinusoidal loading with progressive amplitude. Afterwards we simulated an open book injury and performed fixation with three different configurations of a modular fixation system (1-, 2- or 4-rod configuration) in randomized order. Subsequently, the specimens were subjected to 3 cyclic tests with the same loading protocol as previously defined. Finally, each construct was cyclically tested to failure keeping the final rod configuration.Findings We detected significantly greater mobility after 1-rod-fixation and no significant differences after 2-rod or 4-rod-fixation compared to the intact symphysis condition. In the destructive test series the 4-rod-fixation failed first followed by the 1-rod-fixation. The 2-rod-fixation sustained almost 3 times as many load cycles prior to failure as the 4-rod-fixation, whereas the 1-rod-fixation sustained twice as many cycles as the 4-rod-fixation.Interpretation In conclusion, flexible fixation of the ruptured pubic symphysis in human specimens shows superior behavior with respect to load bearing capacity and ability to withstand cyclic loading compared to stiff constructs. [ABSTRACT FROM AUTHOR]

Background: Syndesmotic diastasis is a common injury. Syndesmotic bolt and tightrope are two of the commonly used methods for the fixation of syndesmotic diastasis. Syndesmotic bolt can be used to reduce and maintain the syndesmosis. However, it cannot permit the normal range of motion of distal tibiofibular joint, especially the rotation of the fibula. Tightrope technique can be used to provide flexible fixation of the syndesmosis. However, it lacks the ability of reducing the syndesmotic diastasis. To combine the advantages of both syndemostic bolt and tightrope techniques and simultaneously avoid the potential disadvantages of both techniques, we designed the assembled bolt-tightrope system (ABTS). The purpose of this study was to evaluate the primary effectiveness of ABTS in treating syndesmotic diastasis. Methods: From October 2010 to June 2011, patients with syndesmotic diastasis met the inclusion criteria were enrolled into this study and treated with ABTS. Patients were followed up at 2, 6 weeks and 6, 12 months after operation. The functional outcomes were assessed according to the American Orthopedic Foot and Ankle Society (AOFAS) scores at 12 months follow-up. Patients' satisfaction was evaluated based upon short form-12 (SF-12) health survey questionnaire. The anteroposterior radiographs of the injured ankles were taken, and the medial clear space (MCS), tibiofibular overlap (TFOL), and tibiofibular clear space (TFCS) were measured. All hardwares were routinely removed at 12-month postoperatively. Follow-ups continued. The functional and radiographic assessments were done again at the latest follow-up. Results: Twelve patients were enrolled into this study, including 8 males and 4 females with a mean age of 39.5 years (range, 26 to 56 years). All patients also sustained ankle fractures. At 12 months follow-up, the mean AOFAS score was 95.4 (range, 85 to 100), and all patients were satisfied with the functional recoveries. The radiographic MCS, TFOL, and TFCS were within the normal range in all patients. After hardware removal, follow-up continued. At the latest follow-up (28 months on average, (range, 25 to 33 months) from internal fixation), the mean AOFAS score was 96.3 (range, 85 to 100), without significant difference with those assessed at 12 months after fixation operations. No syndesmotic diastasis reoccurred based upon the latest radiographic assessment. Conclusions: ABTS can be used to reduce the syndesmotic diastasis and provide flexible fixation in a minimally invasive fashion. It seems to be an effective alternative technique to treat syndesmotic diastasis. [ABSTRACT FROM AUTHOR]

The article reports on research conducted to investigate whether abduction stress would provoke greater post-injury motion than axial weightbearing between the medial cuneiform and the base of the second metatarsal in ligamentous Lisfranc injury. Researchers evaluated 25 pairs of feet. They found that significant amounts of motion are produced between the bones after a ligamentous Lisfranc injury and that abduction stress may be valuable when diagnosing ligamentous Lisfranc injury.

Syndesmotic injuries in the setting of ankle fracture are critically important to diagnosis and treat to restore an anatomic tibiotalar relationship. Physical examination and clinical suspicion remain critically important for diagnosis. Ultrasound examination and weight-bearing computed tomography scans are evolving to help diagnosis more subtle injuries. Although flexible syndesmotic fixation may decrease malreduction rates, the benefits over rigid fixation is the subject of ongoing study. Anatomic reduction remains critical regardless of fixation choice. Routine removal of rigid syndesmotic hardware does not seem to offer substantial clinical improvement in pain or range of motion; however, broken hardware may cause irritation., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Syndesmosis injury may occur in a wide variety of clinical scenarios. Accurate diagnosis and anatomic reconstruction are necessary for optimizing clinical outcomes. The management considerations of syndesmotic injuries with associated proximal fibula fractures are reviewed. Methods to improve the accuracy of syndesmotic reduction are outlined. The management of fractures of the posterior malleolus, Chaput tubercle, and Wagstaffe tubercle is discussed with an emphasis on their contributions to syndesmotic stability. The evolving role of flexible fixation for syndesmosis injuries is discussed. Causes and strategies for dealing with loss of reduction and malreduced syndesmotic injuries are presented., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Flexible fixation has been described and utilized in various aspects of foot and ankle surgery over the past several decades. In regards to ankle surgery, flexible fixation devices have been used for stabilization of the ankle syndesmosis and augmentation of lateral collateral ankle ligament repair. In the foot, flexible fixation devices have been incorporated into hallux valgus or varus correction, Lisfranc injury repair, and more recently spring ligament repair augmentation. This article reviews the various applications for flexible fixation in foot and ankle surgery, as well as evidence-based literature on surgical applications and clinical outcomes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: To compare the effectiveness of flexible fixation and rigid fixation in the treatment of ankle pronation-external rotation fractures with distal tibiofibular syndesmosis., Methods: A retrospective analysis was made on the clinical data of 50 patients with ankle pronation-external rotation fractures and distal tibiofibular syndesmosis treated between January 2013 and December 2015. Suture-button fixation was used in 23 patients (flexible fixation group) and cortical screw fixation in 27 patients (rigid fixation group). There was no significant difference in age, gender, weight, side, fracture type, and time from trauma to surgery between 2 groups ( P >0.05). The operation time, medial clear space (MCS), tibiofibular clear space (TFCS), tibiofibular overlap (TFO), American Orthopaedic Foot and Ankle Society (AOFAS) score, and Foot and Ankle Disability Index (FADI) score were compared between 2 groups., Results: The operation time was (83.0±9.1) minutes in the flexible fixation group and was (79.6±13.1) minutes in the rigid fixation group, showing no significant difference ( t =1.052, P =0.265). All patients achieved healing of incision by first intention. The patients were followed up 12-20 months (mean, 14 months). The X-ray films showed good healing of fracture in 2 groups. There was no screw fracture, delayed union or nounion. The fracture healing time was (12.1±2.5) months in the flexible fixation group and was (11.3±3.2) months in the rigid fixation group, showing no significant difference between 2 groups ( t =1.024, P =0.192). Reduction loss occurred after removal of screw in 2 cases of the rigid fixation group. At last follow-up, there was no significant difference in MCS, TFCS, TFO, AOFAS score and FADI score between 2 groups ( P >0.05)., Conclusion: Suture-button fixation has similar effectiveness to screw fixation in ankle function and imaging findings, and flexible fixation has lower risk of reduction loss of distal tibiofibular syndesmosis than rigid fixation.

Background: Extent and orientation of interfragmentary movement (IFM) are crucially affecting course and quality of fracture healing. The effect of different configurations for implant fixation on successful fracture healing remain unclear. We hypothesize that screw type and configuration of locking plate fixation profoundly influences stiffness and IFM for a given load in a distal femur fracture model.Methods: Simple analytical models are presented to elucidate the influence of fixation configuration on construct stiffness. Models were refined with a consistent single-patient-data-set to create finite-element femur models. Locking plate fixation of a distal femoral 10mm-osteotomy (comminution model) was fitted with rigid locking screws (rLS) or semi-rigid locking screws (sLS). Systematic variations of screw placements in the proximal fragment were tested. IFM was quantitatively assessed and compared for different screw placements and screw types.Results: Different screw allocations significantly affect IFM in a locking plate construct. LS placement of the first screw proximal to the fracture (plate working length, PWL) has a significant effect on axial IFM (p < 0.001). Replacing rLS with sLS caused an increase (p < 0.001) of IFM under the plate (cis-cortex) between +8.4% and +28.1% for the tested configurations but remained constant medially (<1.1%, trans-cortex). Resultant shear movements markedly increased at fracture level (p < 0.001) to the extent that plate working length increased. The ratio of shear/axial IFM was found to enhance for longer PWL. sLS versus rLS lead to significantly smaller ratios of shear/axial IFM at the cis-cortex for PWL of ≥ 62 mm (p ≤ 0.003).Conclusion: Mechanical frame conditions can be significantly influenced by type and placement of the screws in locking plate osteosynthesis of the distal femur. By varying plate working length stiffness and IFM are modulated. Moderate axial and concomitantly low shear IFM could not be achieved through changes in screw placement alone. In the present transverse osteotomy model, ratio of shear/axial IFM with simultaneous moderate axial IFM is optimized by the use of appropriate plate working length of about 42-62 mm. Fixation with sLS demonstrated significantly more axial IFM underneath the plate and may further contribute to compensation of asymmetric straining. [ABSTRACT FROM AUTHOR]