A biomechanical analysis of a tensioned suture device in the fixation of the ligamentous Lisfranc injury

The Use of Knotless Suture Tape Construct vs Screw Fixation for Lisfranc Injuries: A Cadaveric Biomechanical Study

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.

Suture button fixation yields high levels of patient reported outcomes, return to sport, and stable fixation in isolated Lisfranc injuries: A systematic review

IMPORTANCE

Lisfranc injuries remain a significant, but often misdiagnosed, orthopaedic injury. Alongside the traditional methods of surgical fixation, including arthrodesis and open reduction and internal fixation with screws, suture button fixation is an emerging technique.

OBJECTIVES

The purpose of this study is to investigate the efficacy of suture button fixation for treatment of Lisfranc injuries through a systematic review.

EVIDENCE REVIEW

A comprehensive literature review was conducted according to the preferred reporting items for systematic reviews using PubMed, Embase, Web of Science, and Cochrane databases for original, English-language studies observing outcomes of Lisfranc injury until August 19, 2022. The clinical studies with evidence level I-IV and at least a 12 month follow-up after the index surgery were included if they examined quantifiable outcomes of Lisfranc injury treated with suture button. Articles were excluded if they included case reports, systematic reviews, comments, editorials, surveys, animal studies, or biomechanical/cadaveric studies. Variables extracted from text and figures include demographic information, return to sport measures, patient reported outcomes, and complications.

FINDINGS

Of the 10 studies included, there were 186 total patients with an age range of 13-72. In every study, all patients were able to return to sport or activity with a return time averaging from 10.8 to 25.9 weeks. Postoperative American Orthopaedic Foot and Ankle Society scores ranged from 83.5 to 97.0 while pain Visual Analogue Scale ranged from 0.6 to 2.5. Complications were reported in four studies at a rate of 7.7% including two cases of diastasis, two cases of paraesthesia, one case of button irritation, and one of postoperative degenerative joint disease, with no reported revisions.

CONCLUSIONS AND RELEVANCE

In our systematic review, suture button fixation shows high levels of patient reported outcomes, return to sport, and stable fixation in isolated Lisfranc injuries. This surgical technique provides a physiologic reduction across the Lisfranc joint and reduces the need for reoperation including removal of hardware. However, further evidence such as large sample size high-quality randomized controlled trials is needed to draw a definitive conclusion regarding the best treatment for Lisfranc injuries.

LEVEL OF EVIDENCE

Level IV, Systematic Review of Level III and IV studies.

Clinical and Biomechanical Outcomes of Suture Button Fixation for Ligamentous Lisfranc Injury: A Systematic Review and Meta-analysis

Background

Flexible ligamentous fixation has increased in popularity for the treatment of ligamentous Lisfranc injury, but the optimal fixation strategy is unclear.

Purpose

To review the biomechanical, clinical, and radiographic results of ligamentous Lisfranc injuries treated with flexible fixation.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic literature review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed/Medline and Google Scholar literature databases were queried for clinical and biomechanical (cadaveric) studies relating to flexible fixation of ligamentous Lisfranc injury. Outcomes of interest included patient-reported outcome scores, clinical/biomechanical results, radiographic alignment, and return to activity. Where appropriate, meta-analysis of the postoperative outcomes was performed.

Results

Of the 34 initial studies, 14 articles (243 feet) were included in the analysis. In the 11 clinical studies (216 patients), the mean postoperative American Orthopaedic Foot & Ankle Society score was 90.1 (n = 150; 6 studies) and the mean visual analog scale score was 1.5 (n = 137; 5 studies). The rate of return to activity was 100% (n = 35; 5 studies), and 100% of patients maintained radiographic alignment postoperatively (n = 62; 6 studies). No complications or subsequent hardware removals were reported. Of the 3 biomechanical studies (27 feet), 1 study found significantly greater change in diastasis under axial load between intact and postfixation ligaments with suture button versus screw fixation (+1.1 vs -0.1 mm; P < .05), another found no difference in the decrease in diastasis under axial load between the injured state and screw or suture button fixation (1.2 vs 1.0 mm; P = .5), and the third found no difference in displacement between intact and either screw or suture button fixation under either axial (intact vs screw: 1.0 vs 2.0 mm, P = .1; intact vs suture button: 0.6 vs 1.8 mm, P = .1) or abduction (intact vs screw: 1.5 vs 1.1 mm, P = .5; intact vs suture button: 1.3 vs 2.1 mm, P = .1) load.

Conclusion

Flexible fixation use in the treatment of ligamentous Lisfranc injury was found to have significant potential as a fixation option, as demonstrated by excellent clinical results. Biomechanical evidence was inconclusive but suggested a trend toward decreased diastasis in specimens fixed with screws compared with suture buttons.

Management of Lisfranc Injuries: A Critical Analysis Review

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There is a spectrum of midtarsal injuries, ranging from mild midfoot sprains to complex Lisfranc fracture-dislocations.

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Use of appropriate imaging can reduce patient morbidity, by reducing the number of missed diagnoses and, conversely, avoiding overtreatment. Weight-bearing radiographs are of great value when investigating the so-called subtle Lisfranc injury.

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Regardless of the operative strategy, anatomical reduction and stable fixation is a prerequisite for a satisfactory outcome in the management of displaced injuries.

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Fixation device removal is less frequently reported after primary arthrodesis compared with open reduction and internal fixation based on 6 published meta-analyses. However, the indications for further surgery are often unclear, and the evidence of the included studies is of typically low quality. Further high-quality prospective randomized trials with robust cost-effectiveness analyses are required in this area.

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We have proposed an investigation and treatment algorithm based on the current literature and clinical experience of our trauma center.

Lisfranc Injuries in the Athlete

LisFranc injuries in the active, athletic, and military populations can be devastating injuries. There has been much debate over open reduction and internal fixation versus arthrodesis as primary treatment in these injuries. This article aims to present the existing evidence-based medicine to help guide appropriate treatment in this population. With the introduction of flexible fixation, the variety of ways to address these injuries surgically has expanded.

Comparison of flexible fixation and screw fixation for isolated Lisfranc ligament injuries: A protocol for a meta-analysis of comparative studies

BACKGROUND

The frequency of isolated Lisfranc ligament (ILL) injuries has been increasing recently with the increase in low-energy trauma resulting from sports injuries. For ILL injuries, the optimal method of fixation still remains controversial. The traditional fixation method is achieved by trans-articular screws, but recently, dorsal bridge plates and suture button (SB) fixation have become alternatives. Some biomechanical studies have showed that SB fixation can provide adequate strength compared to trans-articular screws. Therefore, a meta-analysis is imperative to provide evidence on whether flexible fixation is comparable to screw fixation for treatment of ILL injuries.

METHODS

We will conduct a comprehensive literature search in PubMed, Cochrane Library, EMBASE and Web of Science databases and for comparative studies. We will apply the risk-of-bias tool of the Cochrane Collaboration for Randomized Controlled Trials to assess the methodological quality. Risk-of-Bias Assessment Tool for Non-randomized Studies was used to evaluate the quality of comparative studies. Statistical analysis will be conducted using RevMan 5.4 software (Cochrane Collaboration, London, England).

RESULTS

This systematic review will evaluate the functional outcomes and radiographic results of flexible fixation for treatment of ILL injuries.

CONCLUSION

The conclusion of this study will provide evidence for judging whether flexible fixation is superior to screw fixation for treatment of ILL injuries.

Biomechanical Comparison of Fiber Tape Device Versus Transarticular Screws for Ligamentous Lisfranc Injury in a Cadaveric Model

BACKGROUND

The preferred method of fixation and surgical treatment for ligamentous Lisfranc injuries is controversial. Transarticular screws, bridge plating, fusion, and flexible fixation have been described, yet none have demonstrated superiority. Furthermore, screw fixation and plating often require secondary surgery to remove implants, leading surgeons to seek alternative fixation methods.

PURPOSE

To compare transarticular screws and a fiber tape construct under a spectrum of biomechanical loads by evaluating the diastasis at 3 joints in the Lisfranc complex.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight matched pairs of fresh, previously frozen lower extremity cadaveric specimens were fixed with either 2 cannulated transarticular crossed screws or a fiber tape construct with a supplemental intercuneiform limb. The diastasis between bones was measured at 3 midfoot joints in the Lisfranc complex: the Lisfranc articulation, the second tarsometatarsal joint, and the intercuneiform joint. Measurements were obtained for the preinjured, injured, and fixation conditions under static loading at 50% donor body weight. Specimens then underwent cyclic loading performed at 1 Hz and 100 cycles, based on 100-N stepwise increases in ground-reaction force from 100 to 2000 N, to simulate postoperative loading from the partial weightbearing stage to high-energy activities. Failure of fixation was defined as diastasis ≥2 mm at the Lisfranc articulation (second metatarsal-medial cuneiform joint).

RESULTS

There were no significant differences in diastasis detected at the Lisfranc articulation or the intercuneiform joint throughout all loading cycles between groups. All specimens endured loading up to 50% body weight + 1400 N. Up to and including this stage, there were 2 failures in the cannulated transarticular crossed-screw group and none in the fiber tape group.

CONCLUSION

The fiber tape construct with a supplemental intercuneiform limb, which does not require later removal, may provide comparable biomechanical stability to cannulated transarticular crossed screws, even at higher loads.

CLINICAL RELEVANCE

Ligamentous Lisfranc injuries are common among athletes. Therefore, biomechanical evaluations are necessary to determine stable constructs that can limit the time to return to play. This study compares the biomechanical stability of 2 methods of fixation for ligamentous injury through a wide spectrum of loading, including those experienced by athletes.

Shortening the Return-to-Play Times in Elite Athletes With Unstable Isolated Lisfranc Ligament Injuries Using a Knotless Interosseous Suture Button: Case Series and Literature Review

Background:

Isolated unstable Lisfranc ligament injuries in elite athletes are associated with a lengthy period of rehabilitation and prolonged absence from competition.

Purpose:

To assess the efficacy of a knotless, interosseous suture button system for repairing isolated unstable ligamentous Lisfranc injuries and its capacity to allow accelerated rehabilitation with earlier weightbearing and return-to-play times in elite athletes.

Study Design:

Case series; Level of evidence, 4.

Methods:

The authors retrospectively reviewed data from a prospectively compiled database for elite athletes treated by a single surgeon. All included patients had clinical and magnetic resonance imaging evidence of an unstable isolated complete ligamentous Lisfranc injury requiring surgical reduction and stabilization. All patients underwent surgery using a knotless interosseous suture button to achieve stabilization, followed by a standardized postoperative regimen involving full weightbearing at 4 weeks, and all had a minimum postoperative follow-up of 2 years.

Results:

Included were 12 patients: 7 National Rugby League (NRL) players, 2 professional dancers, 1 Olympic gymnast, 1 professional wakeboarder, and 1 professional NRL referee. The mean age of the patients was 21.1 years (range, 16-34 years). Ten patients underwent acute surgical stabilization within 3 weeks of the injury, and 2 patients sustained chronic isolated Lisfranc instability that was initially treated nonoperatively. All athletes were able to return to full weightbearing by 4 weeks postoperatively, successfully returned to training by 9 to 12 weeks, and returned to full competition by 12 to 16 weeks. No major complications were reported.

Conclusion:

Knotless interosseous suture button stabilization was a reliable treatment option for both acute and chronic isolated ligamentous Lisfranc injuries in these elite athletes. This technique does not require hardware removal, allows early weightbearing with accelerated rehabilitation, and may shorten the return-to-play interval.

Impact of the Subtle Lisfranc Injury on Foot Structure and Function

BACKGROUND

The subtle Lisfranc injury is the disruption of the osteoligamentary complex between the first cuneiform and the second metatarsal, resulting in minor widening of this space that is often difficult to detect with plain radiographs. In this study, we assessed the results after treatment of the different stages of subtle Lisfranc injuries, focusing on their impact on foot arch anatomy and functionality at short- to midterm follow-up.

METHODS

A retrospective study including patients treated in our center for a subtle Lisfranc injury between 2012 and 2019 was conducted. Demographic, epidemiologic, radiographic, and clinical data were obtained and assessed, focusing on foot arch structure and foot function, which was evaluated with the American Orthopaedic Foot & Ankle Society (AOFAS) midfoot score and the Foot Function Index (FFI).

RESULTS

A total of 42 patients with a mean age of 49 ± 17.5 years were included, with an average of 4.3 years' follow-up (range, 1-8). Stage I injuries according to Nunley classification represented 19% and were treated conservatively. Stage II (66.7%) and stage III (14.3%) injuries were treated operatively, via osteosynthesis with screws (74%), K-wires (19%), or plates (7%). Flattening of foot arch after treatment was observed in 42.9% of patients, with significant increases in Costa-Bertani (12 ± 7 degrees), Hibbs (7 ± 6 degrees), and Meary (3 ± 1 degrees) angles. Other complications included complex regional pain syndrome (28.6%) and painful hardware (23.8%). Secondary joint arthrodesis was needed in 16.6% of patients. Chronic pain was present in 71.4% of patients with a mean visual analog scale (VAS) pain score at final follow-up of 4 of 10 points. Results in AOFAS midfoot score and FFI were 87.4 ± 8.3 and 15 ± 6.4, respectively.

CONCLUSION

The subtle Lisfranc injury shows dissociation between the initial relatively mild radiographic changes and important future complications. Chronic pain and foot arch flattening were not uncommon. Overall foot function in the short- or midterm was found to be modestly diminished in this somewhat heterogenous cohort.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

The Lisfranc Injury: A Literature Review of Anatomy, Etiology, Evaluation, and Management

Despite being first described in the 1800s, the Lisfranc injury remains one of the most controversial topics in foot and ankle surgery. From the basic anatomy of the ligament complex to the optimal diagnostic and management methods, new research both sharpens and yet confounds our understanding of this unique injury. This article reviews the literature from established and classic papers to recent studies evaluating newer techniques. We discuss the unique bony and ligamentous anatomy, which confer strength to the Lisfranc complex, the typical mechanisms of injury, the most common classification systems, the clinical presentation, current imaging modalities, and conservative and surgical treatment options. We review studies comparing open reduction and internal fixation with primary arthrodesis of acute injuries, in addition to studies evaluating the various methods for obtaining fixation, including intra-articular screws, dorsal plates, and flexible fixation. It is clear from this review that despite the vast number of studies in the literature, much is still to be learned about the diagnosis and management of this challenging injury.Levels of Evidence: Level V: Expert opinion.

Treatment of Lisfranc Injuries Using Interosseous Suture Button: A Retrospective Review of 84 Cases With a Minimum 3-Year Follow-Up

Lisfranc fracture dislocation is an injury often encountered by the foot and ankle surgeon. This injury, depending on the severity and level of energy, has been shown to lead to posttraumatic osteoarthritis and chronic pain if undiagnosed or improperly managed. The purpose of this study was to retrospectively evaluate the surgical repair with the use of an interosseous suture button for Lisfranc injuries with isolated ligamentous disruption. From 2008 through 2016, 104 patients were consecutively enrolled who underwent open reduction internal fixation (ORIF) of the Lisfranc complex with a suture button and stabilization of the medial and intermediate cuneiform with a 4.0-mm screw. Eighty-four patients were available for a 3-year minimum follow-up. The mean return to full weightbearing was 11 days protected in a controlled ankle motion (CAM) boot. American Orthopedic Foot & Ankle Society (AOFAS) and visual analog scale (VAS) scores improved from 30 and 8.4, respectfully, preoperatively to 90 and 1.3 postoperatively. The mean preoperative step-off between the second metatarsal base and intermediate cuneiform was found to be 3.15 mm. The immediate postreduction weightbearing radiograph measured 0.25 mm and 0.43 mm at the final follow-up evaluation, a difference that was found to be significant. There were no revision arthrodeses performed and no removal of the suture button during this time period. ORIF using an interosseous suture button appears to have an adequate medium-term patient satisfaction; however, there is evidence of minimal diastasis in some patients at 3 years postoperatively in ligamentous Lisfranc fracture dislocations.

Suture Button vs Conventional Screw Fixation for Isolated Lisfranc Ligament Injuries

BACKGROUND

Suture buttons have been used for isolated Lisfranc ligament (ILL) fixation. However, no study has reported on its clinical and radiologic outcomes.

METHODS

In this retrospective comparative study, patients with ILL injuries were divided into 2 groups according to the treatment method: 32 conventional screw group and 31 suture button group. The clinical and radiologic outcomes at preoperation, 6 months and 1 year postoperation, and last follow-up period were measured. Plantar foot pressure was measured at postoperative month 6 months. Postoperative complications at the last follow-up were evaluated.

RESULTS

The suture button group showed better American Orthopaedic Foot & Ankle Society midfoot scale (P < .001) and visual analog scale (P < .001) scores compared with the conventional screw fixation group at the postoperative month 6 period before screw removal. However, no significant difference in clinical outcome between the 2 groups was found at postoperative year 1 or last follow-up. No differences in radiologic outcomes were found between the 2 groups. Plantar foot pressure was significantly elevated in the conventional screw group at the great toe and first metatarsal head area compared with the contralateral foot just before screw removal. Recurrent Lisfranc joint diastasis was found in a single case in the conventional screw group and 2 cases in the suture button group.

CONCLUSION

Suture button fixation in the treatment of ILL injuries may provide comparable fixation stability and clinical outcome with conventional screw fixation in the early postoperative period.

LEVEL OF EVIDENCE

Level III, retrospective case-control study, therapeutic.

Biomechanical Comparison of Fibertape Device Repair Techniques of Ligamentous Lisfranc Injury in a Cadaveric Model

BACKGROUND

Lisfranc ligamentous injuries are complex, and their treatment, along with the preferred method of fixation, is controversial. Implementing a flexible synthetic augmentation device (fibertape) has been described as an alternative to traditional screw fixation. This biomechanical study evaluated two fibertape devices with interference screw fixation: InternalBrace, and InternalBrace with supplementary intercuneiform stabilization.

METHODS

The diastasis and relative angular displacement between bones were measured at three midfoot joints in the Lisfranc articulation. Measurements were obtained for the pre-injured, injured, and post-fixation stages under static loading. Specimens then underwent stepwise increases in cyclic loading performed at 1 Hz and 100 cycles, at 100 N ground reaction force intervals from 500 to 1200 N to simulate postoperative loading, and then up to 1800 N to simulate high loads. Failure of fixation was defined as diastasis greater than 2 millimeters at the second-metatarsal - medial-cuneiform joint.

RESULTS

InternalBrace specimens demonstrated failures in 3 of 9 (33%) specimens at cyclic loads of 1000 N. Conversely, InternalBrace with Supplementary Limb specimens had 1 failure at 1200 N. The difference in diastasis at the second metatarsal-medial cuneiform joint was statistically significant between the two groups at higher loads of 1600N (p = 0.019) and 1800N (p = 0.029).

CONCLUSION

The use of InternalBrace for ligamentous Lisfranc injuries appears to provide a biomechanically viable alternative for withstanding early postoperative protected weight bearing. Furthermore, the use of a supplementary limb in addition to the InternalBrace fibertape fixation method appears to enhance its biomechanical efficacy.

Case Study: The Conservative Management of a Complex Mid Foot Injury in an Elite Professional Footballer

Lisfranc injuries, often accompanied with tarsometatarsal joint (TMTJ) disruption, are not well documented in football despite becoming increasingly more prevalent within other athletic populations. Currently there is a paucity of evidence documenting prognosis, rehabilitation strategy and outcome. The presented case summarizes the conservative rehabilitation and return to play of a 26-year-old elite professional footballer who presented with a Lisfranc injury alongside a 3^rd TMTJ coalition stress response. Injury was sustained when landing awkwardly from a jump causing the midfoot to be forced into a hyper-plantarflexed position. Palpation identified tenderness over the 2^nd and 3^rd MT, with a positive piano key test. Magnetic resonance imaging (MRI), computed tomography (CT), stork view x-ray and review from a leading foot and ankle specialist confirmed diagnosis, post-contradictory MRI results. Presented is a summary of the assessment process, conservative management of the injury and the resultant rehabilitation process followed, which led to the successful return to play of the athlete.

Optimizing Return to Play for Common and Controversial Foot and Ankle Sports Injuries

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Surgical decision-making should consider factors to help optimize return to play for athletes with foot and ankle injuries, including injuries to the syndesmosis, the Achilles tendon, the fifth metatarsal, and the Lisfranc complex. Understanding influential factors on return to play may help orthopaedic surgeons counsel athletes and coaches on expectations for a timeline to return to play and performance metrics.

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Outcomes after rigid and flexible fixation for syndesmotic injuries are generally favorable. Some data support an earlier return to sport and higher functional scores with flexible fixation, in addition to lower rates of reoperation and a decreased incidence of malreduction, particularly with deltoid repair, if indicated.

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Minimally invasive techniques for Achilles tendon repair have been shown to have a decreased risk of wound complications. Athletes undergoing Achilles repair should expect to miss a full season of play to recover.

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Athletes with fifth metatarsal fractures have better return-to-play outcomes with surgical management and can expect a high return-to-play rate within approximately 3 months of surgery.

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Percutaneous treatment of Lisfranc injuries may expedite return to play relative to open procedures.

Subtle Lisfranc Injuries: Fix It, Fuse It, or Bridge It?

The management of Lisfranc injuries is challenging considering the broad spectrum of energy involved and highly variable clinical presentation. Despite the advances in surgical techniques, subtle Lisfranc injuries can lead to chronic pain and permanent disability. Surgical treatment is mandatory for all the unstable injuries; however, the best surgical technique remains controversial. The most predictive factor for a successful outcome is the maintenance of anatomic alignment; therefore, the selection of the appropriate surgical technique is of paramount importance. This article reviews the current treatment options and describes the selection of the surgical technique based on the different clinical presentations.

Change in the First Cuneiform-Second Metatarsal Distance After Simulated Ligamentous Lisfranc Injury Evaluated by Weightbearing CT Scans

BACKGROUND

This study aimed to investigate the widening between the first cuneiform (C1) and second metatarsal (M2) in a Lisfranc ligamentous complex (LLC) joint injury model subjected to successive ligament dissections evaluated by weightbearing computed tomography (CT) scans.

METHODS

Twenty-four intact cadaveric feet served as the control (condition 1). Each component of the LLC (dorsal, interosseous, and plantar ligaments-conditions 2, 3, and 4, respectively) were then sequentially dissected. The specimens were equally randomized to 1 of 3 additional dissections (first or second tarsometatarsal [TMT] joint capsule or first-second intercuneiform ligament [ICL]-conditions 5a, 5b, and 5c, respectively). One additional ligament was then randomly transected (eg, condition 6ac-transection of the first TMT capsule and ICL). Finally, the remaining ligament was transected (condition 7). After each dissection, CT scans were acquired under nonweightbearing (NWB, 0 kg), partial-weightbearing (PWB, 40 kg), and full-weightbearing (FWB, 80 kg) conditions. The distance between the lateral border of C1 and the medial border of M2 was assessed to evaluate diastasis. Linear regressions with 95% CIs and converted q values were used to compare the measured data.

RESULTS

No significant differences were found within the control. In condition 4, an average axial plane widening relative to control of 1.6 mm (95% CI, 1.5-1.8) and 2.1 mm (95% CI, 1.9-2.2) was observed under PWB and FWB. A coronal plane widening of 1.5 mm (95% CI, 1.3-1.6) and 1.9 mm (95% CI, 1.7-2.1) under PWB and FWB, respectively, was measured. A 95% CI of at least a 2-mm widening during PWB was demonstrated in 5c, 6ac, 6bc, and 7.

CONCLUSIONS

Weightbearing computed tomography (WBCT) scans were used to detect ligamentous Lisfranc injuries in a cadaveric model. Relative axial widening greater than 1.5 mm under PWB conditions could indicate a complete LLC injury. Complete transection of the intercuneiform 1-2 ligament was required to detect a 2-mm widening in the nonweightbearing condition.

CLINICAL RELEVANCE

This study provides insight on the detection of various severities of LLC injuries using WBCT imaging.

Comparison of Suture-Augmented Ligamentplasty to Transarticular Screws in a Lisfranc Cadaveric Model

BACKGROUND

Lisfranc injuries represent a spectrum of trauma from high-energy lesions, with significant instability of the midfoot, to low-energy lesions, with subtle subluxations or instability without gross displacement. Recently, treatment options that allow for physiologic fixation of this multiplanar joint are being evaluated. The purpose of this study was to analyze the stability of a cadaveric Lisfranc injury model fixed with a novel suture-augmented neoligamentplasty in comparison with a traditional transarticular screw fixation construct.

METHODS

Twenty-four fresh-frozen, matched cadaveric leg and foot specimens (12 individuals younger than 65 years of age) were used for this study. Two different types of Lisfranc ligament injuries were tested: partial and complete. Two different methods of fixation were compared: transarticular screws and augmented suture ligamentplasty with FiberTape. Specimens were fixed to a rotation platform in order to stress the joints while applying 400 N of axial load and internal and external rotation. Six distances were measured and compared between the intact, injured, and fixed states with a 3D Digitizer arm, in order to evaluate the stability between them. Analysis of variance was used with P < .05 considered significant.

RESULTS

Using distribution graphs and analyzing the grouped data, it was observed that there was no difference between the 2 stabilization methods, but the augmented suture ligamentplasty presented lower variability and observed distance shortenings were more likely to be around the mean. The variability of the stabilization with screws was 2.9 times higher than that with tape (P < .001).

CONCLUSION

We suggest that augmented suture ligamentplasty can achieve similar stability to classic transarticular screws, with less variability.

CLINICAL RELEVANCE

This cadaveric study adds new information on the debate about Lisfranc lesions treatment. Flexible fixations, such as the synthethic ligamentplasty used, can restore good stability such as conventional transarticular screws.

Biomechanical Evaluation With a Novel Cadaveric Model Using Supination and Pronation Testing of a Lisfranc Ligament Injury

Background:

Lisfranc joint injuries can be due to direct or indirect trauma and while the precise mechanisms are unknown, twisting or axial force through the foot is a suspected contributor. Cadaveric models are a useful way to evaluate injury patterns and models of fixation, but a frequent limitation is the amount of joint displacement after injury. The purpose of this study was to test a cadaveric model that includes axial load, foot plantarflexion and pronation-supination motion, which could re-create bone diastasis similar to what is seen in subtle Lisfranc injuries. Our hypothesis was that applying pronation and supination motion to a cadaveric model would produce reliable and measurable bone displacements.

Methods:

Twenty-four fresh-frozen lower leg cadaveric specimens were used. The medial (C1) and intermediate (C2) cuneiforms and the first (M1) and second (M2) metatarsal bones were marked. A complete ligament injury was performed between C1-C2 and C1-M2 in 12 specimens (group 1), and between C1-C2, C1-M2, C1-M1, and C2-M2 in 12 matched specimens (group 2). Foot pronation and supination in addition to an axial load of 400 N was applied to the specimens. A 3D digitizer was used to measure bone distances.

Results:

After ligament injury, distances changed as follows: C1-C2 increased 3 mm (23%) with supination; C1-M2 increased 4 mm (21%) with pronation (no differences between groups). As expected, distances between C1-M1 and C2-M2 only changed in group 2, increasing 3 mm (14%) and 2 mm (16%), respectively (no differences between pronation and supination). M1-M2 and C2-M1 distances did not reach significant difference for any condition.

Conclusions:

Pronation or supination in addition to axial load produced measurable bone displacements in a cadaveric model of Lisfranc injury using sectioned ligaments. Distances M1-M2 and C2-M1 were not reliable to detect injury in this model.

Clinical Relevance:

This new cadaveric Lisfranc model included foot pronation-supination in addition to axial load delivering measurable bone diastasis. It was a reliable Lisfranc cadaveric model that could be used to test different Lisfranc reconstructions.

Flexible fixation for ligamentous lisfranc injuries

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.

Flexible Fixation Technique for Lisfranc Injuries

Injuries to the Lisfranc complex range from purely ligamentous disruptions to fracture-dislocations of the tarsometatarsal joint. Treatment options include closed/open reduction with percutaneous pinning, open reduction and internal fixation (ORIF), and primary arthrodesis. We present a ligament reinforcement technique utilizing a flexible fixation device for the treatment of ligamentous Lisfranc injuries. Level of Evidence: Level V, expert opinion.

InternalBrace has biomechanical properties comparable to suture button but less rigid than screw in ligamentous lisfranc model

Purpose

The aim of this study was to investigate the biomechanical properties of the InternalBrace for lisfranc injuries.

Methods

A Sawbone model was developed comparing screw, suture button and InternalBrace.

Results

When loaded in axial tension at 0.5 mm/s, the screw was stiffest (2,240 N/mm), while the InternalBrace (200 N/mm) was stiffer than the suture button (133 N/mm). Cyclic loading with 10,000 cycles of 69 N, 138 N, and 207 N showed the InternalBrace maintained stiffness, but fatigued earlier than the suture button.

Conclusion

The mechanical properties of the InternalBrace support clinical use, but further studies are needed regarding early weight bearing.

Biomechanical comparison of fixation stability using a Lisfranc plate versus transarticular screws

BACKGROUND

To obtain adequate fixation in treating Lisfranc soft tissue injuries, the joint is commonly stabilized using multiple transarticular screws; however iatrogenic injury is a concern. Alternatively, two parallel, longitudinally placed plates, can be used to stabilize the 1st and 2nd tarsometatarsal joints; however this may not provide adequate stability along the Lisfranc ligament. Several biomechanical studies have compared earlier methods of fixation using plates to the standard transarticular screw fixation method, highlighting the potential issue of transverse stability using plates. A novel dorsal plate is introduced, intended to provide transverse and longitudinal stability, without injury to the articular cartilage.

METHODS

A biomechanical cadaver model was developed to compare the fixation stability of a novel Lisfranc plate to that of traditional fixation, using transarticular screws. Thirteen pairs of cadaveric specimens were tested intact, after a simulated Lisfranc injury, and then following implant fixation, using one method of fixation randomly assigned, on either side of each pair. Optical motion tracking was used to measure the motion between each of the following four bones: 1st metatarsal, 2nd metatarsal, 1st cuneiform, and 2nd cuneiform. Testing included both cyclic abduction loading and cyclic axial loading.

RESULTS

Both the Lisfranc plate and screw fixation method provided stability such that the average 3D motions across the Lisfranc joint (between 2nd metatarsal and 1st cuneiform), were between 0.2 and 0.4mm under cyclic abduction loading, and between 0.4 and 0.5mm under cyclic axial loading. Comparing the stability of fixation between the Lisfranc plate and the screws, the differences in motion were all 0.3mm or lower, with no clinically significant differences (p>0.16).

CONCLUSIONS

Diastasis at the Lisfranc joint following fixation with a novel plate or transarticular screw fixation were comparable. Therefore, the Lisfranc plate may provide adequate support without risk of iatrogenic injury to the articular cartilage.

Management of Midfoot Fractures and Dislocations

PURPOSE OF REVIEW

To outline the classic and recent literature of midfoot fractures and dislocations.

RECENT FINDINGS

There has been an evolution of implant technology to include mini-fragment fixation, suture fixation, and staples. Their efficacy is still being elucidated in the literature. Also, there has been a recent push for primary fusion, which we will discuss. Open reduction internal fixation of the midfoot remains to be the gold standard treatment, to which all other treatments are compared. It remains to be seen if adjunct fixation techniques are efficacious enough to provide a good result. Further study is needed to determine which patients are likely to progress to debilitating arthrosis and require fusion.

Management of Tarsometatarsal Joint Injuries

Joint disruptions to the tarsometatarsal (TMT) joint complex, also known as the Lisfranc joint, represent a broad spectrum of pathology from subtle athletic sprains to severe crush injuries. Although injuries to the TMT joint complex are uncommon, when missed, they may lead to pain and dysfunction secondary to posttraumatic arthritis and arch collapse. An understanding of the appropriate anatomy, mechanism, physical examination, and imaging techniques is necessary to diagnose and treat injuries of the TMT joints. Nonsurgical management is indicated in select patients who maintain reduction of the TMT joints under physiologic stress. Successful surgical management of these injuries is predicated on anatomic reduction and stable fixation. Open reduction and internal fixation remains the standard treatment, although primary arthrodesis has emerged as a viable option for certain types of TMT joint injuries.

Minimally invasive stabilization of the distal radioulnar joint: a cadaveric study

This study describes a minimally invasive procedure for stabilization of the distal radioulnar joint, using a suture-button construct placed percutaneously in the direction of the distal oblique bundle in the distal interosseous membrane. In five cadaveric specimens, placement of the suture-button suspension system reduced dorsal displacement of the radius in an unstable distal radioulnar joint to baseline values, both in neutral position and in pronation and supination. These results indicate the possibility of minimally invasive treatment for distal radioulnar joint instability.

Efficacy of open reduction and internal fixation with a miniplate and hollow screw in the treatment of Lisfranc injury

PURPOSE

To investigate efficacy of open reduction and internal fixation with the miniplate and hollow screw in the treatment of Lisfranc injury.

METHODS

Ten cases of Lisfranc injury treated by open reduction, miniplate and hollow screw in our hospital were retrospectively analyzed. There were 6 males and 4 females with age ranging from 25 to 45 years (mean 32 years). Among them, one case was classified as Type A, six Type B and three Type C. Injury mechanism included road traffic accidents (3 cases), fall from height (5 cases) and hit by heavy object (2 cases). All injuries were closed without cerebral trauma or other complicated injuries. The time interval between injury and operation was 6-10 days (average 6.6 days). Postoperatively, the foot function was assessed using Visual Analogue Scales (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) Scales. Healing time and complications were observed.

RESULTS

All patients were followed up for 18-24 months (average 20 months). Anatomic reduction was achieved in all patients on images. There was statistical significance between preoperative score (7.89 ± 0.34) and score at postoperative 8 weeks (0.67 ± 0.13). According to the AOFAS score, 5 cases were defined as excellent, 3 cases as good and 2 cases as fair. During follow-up, there was no wound infection or complications except for osteoarthritis in 2 cases. Healing time ranged from 3 to 6 months with an average of 3.6 months.

CONCLUSION

Anatomical reduction of Lisfranc injury can be achieved by open reduction and internal fixation with the miniplate and hollow screw. Normal structure of Lisfranc joint is regained to a great extent; injured ligaments were also repaired. Therefore, this method offers excellent curative effect and can avoid postoperative complications and improve the patients' quality of life.

Biomechanical analysis of endobutton versus screw fixation after Lisfranc ligament complex sectioning

BACKGROUND

Our goal was to compare diastasis after endobutton and screw fixation after Lisfranc ligament complex sectioning.

METHODS

Twenty-four (12 pairs) fresh-frozen cadaveric feet were assigned to endobutton or screw fixation and loaded to 343N. Displacement (first-second metatarsal bases) was measured in intact feet and after ligament sectioning (Lisfranc, medial-intermediate cuneiform ligaments), fixation, and 10,000 cycles.

RESULTS

The mean change in diastasis for endobutton and screw fixation under initial loading was 1.0mm (95% CI, 0.2-1.9mm) and 0.0mm (95% CI, -0.4 to 0.4mm), respectively (p=0.017). After cyclic loading, diastasis decreased (mean, -0.7mm, 95% CI, -1.2 to -0.1mm) in the endobutton group but was unchanged in the screw group (p=0.035).

CONCLUSIONS

Diastasis after endobutton fixation was significantly greater than after screw fixation under initial loading but did not increase further after cyclic loading.

Suture-button suspensionplasty for thumb carpometacarpal arthritis: a minimum 2-year follow-up

PURPOSE

To retrospectively review the results at a minimum of 2 years of suture-button plasty with partial or full trapeziectomy and suture-button suspensionplasty.

METHODS

We evaluated 21 patients who received suture-button suspensionplasty at least 2 years after surgery. We measured postoperative pinch strength, grip strength, range of motion, and metacarpal height. All patients also completed the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire.

RESULTS

At an average follow-up of 2.8 ± 0.7 years, the mean Quick Disabilities of the Arm, Shoulder, and Hand score was 10 ± 9. Pinch and grip strengths were 86% and 89% of the contralateral limb, respectively. Average first trapezial height was 74% of the contralateral trapezial height. There were no major complications.

CONCLUSIONS

The favorable results of the suture-button suspensionplasty procedure confirm its usefulness in treating thumb carpometacarpal arthritis with minimal risk of complications, ineffective fixation, or loss of function. Subjective and objective outcomes measures are similar to previously described techniques. The benefit of this technique results from the implanted nature of the suspensionplasty elements that require no time to heal, so rehabilitation is begun as early as 10 days postoperatively.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Suture button suspension following trapeziectomy in a cadaver model

BACKGROUND

The safety and the effects of different trajectories on thumb motion of suture-button suspensionplasty post-trapeziectomy are not known.

METHODS

In a cadaveric model, thumb range of motion, trapeziectomy space height, and distance between the device and nerve to the first dorsal interosseous muscle (first DI) were measured for proximal and distal trajectory groups. Proximal trajectory was defined as a suture button angle directed from the thumb metacarpal to the second metacarpal at a trajectory less than 60° from the horizontal; distal trajectory was defined as a suture button angle directed from the thumb metacarpal to the second metacarpal at a trajectory of greater than 60° from the horizontal (Fig. 1).

RESULTS

There were no significant differences in range of motion and trapeziectomy space height between both groups. The device was significantly further away from the nerve to the first DI in the proximal trajectory group compared to the distal trajectory group, but was still safely away from the nerve in both groups (greater than 1 cm).

CONCLUSIONS

These results suggest that the device placement in either a proximal or distal location on the second metacarpal will yield similar results regarding safety and thumb range of motion.

Micro-CT Density Analysis of the Medial Wall of the Human Medial Cuneiform

The human medial cuneiform is incompletely characterized with regard to anatomical morphology, including mineral density and bone quality. Clinically, we have observed failures of fixation by pull-through of devices through relatively soft medial bone. Defining patterns of relative density may provide valuable information regarding implant placement as higher cortical density bone may offer better resistance to such failures. We sought to identify an area of greatest density along the medial wall of the medial cuneiform.Ten fresh-frozen human cadaveric medial cuneiforms underwent micro-computed tomography imaging. Images were analyzed to obtain densities in 4 quadrants along the medial wall of the medial cuneiform. Seven of 10 specimens revealed a maximum density in the plantar distal quadrant of the medial wall of the medial cuneiform. Chi-square goodness-of-fit testing indicated that the density of this quadrant was significantly different from 3 other quadrants (P<.009). Using the Principle of Standard Residuals, the density of the plantar distal quadrant was significantly different than the other 3.We conclude that the plantar distal quadrant of the medial cuneiform contains bone of maximal density when compared to 3 other quadrants. Surgeons who place implants in this region should be aware that this area might offer better resistance to fixation failure.