Comparison of Clamp Reduction and Manual Reduction of Syndesmosis in Rotational Ankle Fractures: A Prospective Randomized Trial

The Radiological Anatomy of the Distal Tibiofibular Joint: A Retrospective Computed Tomography Study

Introduction Distal tibiofibular joint (DTFJ) injuries are commonly encountered in patients with ankle fractures. Achieving optimal fixation is mandatory, but it requires a thorough understanding of the local anatomical relationships. For this reason, we performed a retrospective CT study in healthy ankles to radiologically describe the normal anatomy of the DTFJ and the anatomical relationship of the fibula within the ankle joint. Materials and methods For this study, we retrospectively examined 60 CT scans of healthy, non-injured ankles in a plantigrade position. Patients with prior ankle surgery or systemic diseases with ankle involvement were excluded because we needed to describe the normal anatomy of the joint. The radiological evaluation included the position of the fibula in the fibular notch and the rotational relationship of the fibula with the talus and the medial malleolus. Results Our study included 60 healthy ankles. Thirty-three were right ankles, and 27 were left. The cohort included 36 females and 24 males with a mean age of 48.3 years old. We found that the fibular notch was retroverted on the transverse plane, with the tibiofibular engagement being 0.11 mm (SD=1.57 mm, SE=0.2 mm), at 1 cm proximally to the tibial plafond. Additionally, we observed that the fibula was internally rotated against the lateral talar facet, while the medial and lateral malleolus facets were externally rotated in between. Moreover, we found a strong positive correlation between the incisura retroversion and fibular engagement at 1 cm above the tibial plafond line (Pearson correlation=0.273, p=0.03). Conclusion Our study highlights the importance of gaining a comprehensive understanding of the inherent anatomy of the DTFJ to achieve reduction goals in ankle fractures. According to our results, in ankle fracture treatment, surgeons should aim for anatomical fracture and syndesmotic fixation, with the fibula in internal rotation against the lateral talar facet. Additionally, as normal tibiofibular engagement is borderline, we do not suggest that over-tightening the syndesmotic screws is essential. This study's findings can aid surgeons in reducing the malreduction rates in patients with ankle fractures.

Angle bisector method to determine the accurate angle for tibiofibular syndesmotic fixation: A validation study with 3D-printed anatomical models

PURPOSE

This study aimed to validate the angle bisector method on 3D-printed ankle models to reveal whether it aids in placing syndesmotic screws at an accurate trajectory that is patient- and level-specific and also not surgeon-dependent.

METHODS

DICOM data of 16 ankles were used to create 3D anatomical models. Then the models were printed in their original size and two trauma surgeons performed the syndesmotic fixations with the angle bisector method at 2 cm and 3.5 cm proximal to joint space. Afterward, the models were sectioned to reveal the trajectory of the screws. The photos of the axial sections were processed in a software to determine the centroidal axis which is defined as true syndesmotic axis and analyze its relationship with the screws inserted. The angle between the centroidal axis and syndesmotic screw was measured by two-blinded observers 2 times with 2 weeks interval.

RESULTS

The average angle between the centroidal axis and screw trajectory was 2.4° ± 2° at 2 cm-level and 1.3° ± 1.5° at 3.5 cm-level, indicating a reliable direction with minimal differences at both levels. The average distance between fibular entry points of the centroidal axis and screw trajectory was less than 1 mm at both levels indicating that the angle bisector method can provide an excellent entry point from fibula for syndesmotic fixation. The inter- & intra-observer consistencies were excellent with all ICC values above 0.90.

CONCLUSION

The angle bisector method provided an accurate syndesmotic axis for implant placement which is patient- & level-specific and not surgeon-dependent, in 3D-printed anatomical ankle models.

Effect of Posterior Malleolar Fixation on Syndesmotic Stability

BACKGROUND

Transsyndesmotic fixation with suture buttons (SBs), posterior malleolar fixation with screws, and anterior inferior tibiofibular ligament (AITFL) augmentation using suture tape (ST) have all been suggested as potential treatments in the setting of a posterior malleolar fracture (PMF). However, there is no consensus on the optimal treatment for PMFs.

PURPOSE

To determine which combination of (1) transsyndesmotic SBs, (2) posterior malleolar screws, and (3) AITFL augmentation using ST best restored native tibiofibular and ankle joint kinematics after 25% and 50% PMF.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty cadaveric lower-leg specimens were divided into 2 groups (25% or 50% PMF) and underwent biomechanical testing using a 6 degrees of freedom robotic arm in 7 states: intact, syndesmosis injury with PMF, transsyndesmotic SBs, transsyndesmotic SBs + AITFL augmentation, transsyndesmotic SBs + AITFL augmentation + posterior malleolar screws, posterior malleolar screws + AITFL augmentation, and posterior malleolar screws. Four biomechanical tests were performed at neutral and 30° of plantarflexion: external rotation, internal rotation, posterior drawer, and lateral drawer. The position of the tibia, fibula, and talus were recorded using a 5-camera motion capture system.

RESULTS

With external rotation, posterior malleolar screws with AITFL augmentation resulted in best stability of the fibula and ankle joint. With internal rotation, all repairs that included posterior malleolar screws stabilized the fibula and ankle joint. Posterior and lateral drawer resulted in only small differences between the intact and injured states. No differences were found in the efficacy of treatments between 25% and 50% PMFs.

CONCLUSION

Posterior malleolar screws resulted in higher syndesmotic stability when compared with transsyndesmotic SBs. AITFL augmentation provided additional external rotational stability when combined with posterior malleolar screws. Transsyndesmotic SBs did not provide any additional stability and tended to translate the fibula medially.

CLINICAL RELEVANCE

Posterior malleolar fixation with AITFL augmentation using ST may be the preferred surgical method when treating patients with acute ankle injury involving an unstable syndesmosis and a PMF ≥25%.

Characteristics and Effectiveness of Postoperative Rehabilitation Strategies in Ankle Fractures: A Systematic Review

OBJECTIVES

To explore the characteristics and to report on the effectiveness of postoperative rehabilitation strategies for people with an ankle fracture.

DATA SOURCES

PubMed, Cochrane Library, EMBASE, Web of Science, and CINAHL were searched to identify studies published from January 2010 to November 2021.

STUDY SELECTION

Studies that described or evaluated postoperative rehabilitation strategies for surgically repaired ankle fractures were included.

DATA EXTRACTION

Data on postoperative rehabilitation were extracted in accordance with the Template for Intervention Description and Replication guide. Quality was assessed using the National Heart, Lung, and Blood Institute's Study Quality Assessment Tools.

DATA SYNTHESIS

Meta-analysis was planned to look at the effectiveness of postoperative rehabilitation strategies. Forty studies described postoperative rehabilitation strategies without evaluating effectiveness, whereas 15 studies focused on evaluating effectiveness. Because of the large variety in postoperative strategies and outcomes, narrative synthesis was deemed most suitable to answer our aims. Characteristics of postoperative rehabilitation strategies varied widely and were poorly described in a way that could not be replicated. Most of the studies (48%) used a late weight-bearing approach, although definitions and details around weight-bearing were unclear.

CONCLUSIONS

Late weight-bearing has been the most common postoperative approach reported in the past 10 years. The variety of definitions around weight-bearing and the lack of details of rehabilitation regimens limit replication and affect current clinical practice. The authors propose to adopt consistent definitions and terminology around postoperative practices such as weight-bearing to improve evidence for effectiveness and ultimately patient outcomes.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Compensation of Dynamic Fixation Systems in the Quality of Reduction of Distal Tibiofibular Joint in Acute Syndesmotic Complex Injuries: A CT-Based Analysis

BACKGROUND

There is an ongoing discussion on how to best stabilize syndesmotic injuries. Previous studies have indicated a better quality of reduction of the distal tibiofibular joint (DTFJ) for the suture button systems compared to syndesmotic screw fixation. Still, the reason for this superiority remains unclear. The aims of this retrospective study were to (1) analyze the deviation of the tibial and fibular drilling tunnels of the suture button system and (2) to compare these to the quality of reduction of the DTFJ assessed on bilateral postoperative CT images.

METHODS

Included were all adult patients who underwent syndesmotic stabilization for an acute injury using a suture button system, with postoperative, bilateral CT imaging over a 10-year period. A total of 147 patients were eligible. Based on individually reconstructed axial CT slices, the postoperative quality of reduction of the DTFJs was rated on bilateral CT images. Furthermore, the rotation and translation of the suture button drilling tunnels were analyzed. Based on these measurements, the intraoperative reduction of the DTFJ was recalculated and again rated. Using these values, the correction potential of suture button systems on the reduction of the DTFJ was analyzed.

RESULTS

(1) The drilling tunnel deviated considerably for both rotation |2.3±2.1 degrees| (range: |0.0-13.1 degrees|) and translation |0.9±0.8 mm| (range: |0-4.3 mm|). Based on the deviation of the drilling tunnels in fibula and tibia, the calculated intraoperative reduction of the DTFJ was classified as malreduced in 35.4%. (2) The DTFJ was postoperatively identified as malreduced in 17% of patients. Overall, the suture button system tended to compensate toward a more anatomical reduction both in the axial and sagittal plane.

CONCLUSION

A suture button system postoperatively deviates and apparently has the capacity to compensate for intraoperative malreduction. Analysis of the drilling tunnels revealed that the use of a rigid fixation system would have doubled the postoperative malreduction rate.

Intraoperative Assessment of Reduction of the Ankle Syndesmosis

PURPOSE OF REVIEW

Postoperative malreduction of the ankle syndesmosis is common, poorly defined, and its assessment is controversial. In the absence of a gold standard method to evaluate the ankle syndesmosis, a variety of techniques have been described. As the knowledgebase expands, data illustrating caveats for such techniques has become available. The purpose of this review is to highlight literature-sourced technical pearls and their related caveats for the intraoperative assessment of the ankle syndesmosis.

RECENT FINDINGS

Although numerical criteria are commonly used to assess syndesmotic reduction, anatomical variation in the healthy population frequently exceeds proposed cutoffs. Patient-specific uninjured anatomy can be defined by comparing to the uninjured contralateral ankle; however, side-to-side variation is present for many anatomical relationships. Advanced imaging (e.g., lateral radiographs, 3-dimensional radiography) can influence intraoperative surgeon decision-making and improve syndesmosis reduction, but minute improvements in syndesmosis reduction may not outweigh increased operating time and costs. Intraoperative imaging is an adjunct, not a replacement for direct visualization or palpation when reducing the syndesmosis. Arthroscopy may benefit younger patients with high physical demands by improving identification of intra-articular pathology absent on MRI. Although anatomical reduction is important to restore pre-injury biomechanics, it is unclear whether differences in reduction quality influence patient-reported outcomes. In the absence of a gold standard, awareness of the options for intraoperative assessment of the syndesmosis and their respective accuracy and limitations reported herein could enhance surgeons' ability to intraoperatively reduce the syndesmosis with the tools currently available.

The Syndesmosis, Part II: Surgical Treatment Strategies

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.

Clinical outcomes of isolated acute instability of the syndesmosis treated with arthroscopy and percutaneous suture-button fixation

INTRODUCTION

To present the short- to midterm clinical outcomes of a series of patients with isolated acute syndesmosis instability treated with arthroscopy and percutaneous suture-button fixation.

MATERIALS AND METHODS

A review of 17 patients treated through the arthroscopic approach. The mean age of the patients was 27.8 years and the mean follow-up was 31.5 months. Clinical and functional evaluations were based on the VAS, AOFAS ankle-hindfoot score and time of return to preinjury level of activities. Imaging analysis was performed with stress radiographs, MRI and CT scan with stress.

RESULTS

The average VAS was 0.5 and the mean AOFAS score was 95.5. Out of the 17 patients, 15 were able to return to their preinjury level of activities. The mean time of return to activities was 5.06 months.

CONCLUSION

Arthroscopic approach and percutaneous suture-button fixation provided satisfactory clinical and functional results for selected patients with ASI at short- to midterm follow-up.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Management of Ankle Fractures With Syndesmotic Disruption: A Survey of Orthopaedic Surgeons

Introduction: With no current “gold standard” fixation strategy for syndesmotic injuries and differences in preferred preoperative and intraoperative diagnostic techniques and criteria, methods of reduction, fixation constructs, and postoperative management, the goals of this study were to determine how orthopaedic surgeons currently manage ankle fractures with concomitant syndesmotic disruption, as well as to identify surgeon demographics predictive of syndesmotic management techniques.

Methods: This study was conducted as a web-based survey of foot and ankle fellowship-trained surgeons, Orthopaedic Trauma Association (OTA) members, and Canadian Orthopaedic Association (COA) members. The survey, sent and completed via the HIPAA-compliant Research Electronic Data Capture (REDCap) system, consisted of 18 questions: 6 surgeon demographic questions and 12 specific syndesmotic management questions regarding perioperative protocols and syndesmotic fixation construct techniques.

Results: One hundred and ten orthopaedic surgeons completed our survey. Years of practice and type of fellowship were found to be the variables that influenced perioperative syndesmotic management strategies the most, while a number of fractures operated on per year, country of practice, and practice setting also influenced management decisions. Additionally, 59% (65/110) surgeons indicated that the way they have managed syndesmotic injuries has changed at some point in their career, while 33% (36/110) specified that they could foresee themselves changing their management of these injuries in the future.

Conclusions: There was significant variability among responders in preoperative and intraoperative assessment technique, fixation construct, screw removal protocol, and postoperative weightbearing protocol. This study raises awareness of differences in and factors predictive of management strategies and should be used for further discussion when determining a potential gold standard for the management of these complex injuries.

Comparison of Different Magnitudes of Applied Syndesmotic Clamp Force: A Cadaveric Study

Overcompression of the ankle syndesmosis was once thought to be improbable. Recent studies using computerized tomography (CT) however, have demonstarted otherwise; raising pertinent questions regarding the factors associated with and consequences of syndesmotic overcompression. The purpose of the present study was to directly compare different magnitudes of applied clamp force on the coronal reduction of ankle syndesmosis. Eight through-the-knee cadaveric specimens were obtained. Fiducial cannulated screws were placed in the tibia and fibula to standardize placement of the reduction clamp's tines. CT scans were obtained as baseline controls, followed by destabilization of the syndesmosis. Reductions were then performed using a clamp equipped with an inline load cell, and objective forces (60, 80, 100, 120, 140, and 160 N) applied sequentially to each of the specimens. The syndesmosis was fixed with a single quadricortical screw, and CT were scans repeated. Applied clamp forces of 60 and 80 N resulted in lateral fibular displacement and undercompression (42.9% and 57.1%, respectively), whereas forces of 140 and 160 N resulted in medial fibular displacement (p = .011 and p = .001) and overcompression (100%). The smallest mediolateral displacements were observed with 100 and 120 N, respectively. Malreduction assessment with CT was superior to traditional radiographs [r(54) = 0.22; 95% confidence interval -0.04 to 0.45; p = .101]. In our cadaveric model, an applied clamp force of 100 N most effectively mitigated iatrogenic coronal syndesmotic malreduction from under- or overcompression. Although additional research is warranted, based on the data, inherent variabilities in the applied clamp force by surgeons appear to contribute to the unacceptably high coronal syndesmotic malreduction rate.

Acute and Chronic Syndesmotic Instability: Role of Surgical Stabilization

Acute and chronic syndesmotic injuries significantly impact athletic function and activities of daily living. Patient history, examination, and judicious use of imaging modalities aid diagnosis. Surgical management should be used when frank diastasis, instability, and/or chronic pain and disability ensue. Screw and suture-button fixation remain the mainstay of treatment of acute injuries, but novel syndesmotic reconstruction techniques hold promise for treatment of acute and chronic injuries, especially for athletes. This article focuses on anatomy, mechanisms of injury, diagnosis, and surgical reduction and stabilization of acute and chronic syndesmotic instability. Fixation methods with a focus on considerations for athletes are discussed.

Necessity of Interfragmentary Lag Screws in Precontoured Lateral Locking Plate Fixation for Supination-External Rotation Lateral Malleolar Fractures

BACKGROUND

Interfragmentary lag screws, protected by a plate, have been applied for many years in the treatment of supination-external rotation (SER) ankle fractures. Recently, similar biomechanical stability was found between fixation completed with a plate and lag screw and a plate alone. The aim of this study was to determine whether interfragmentary lag screws are necessary during precontoured lateral locking plate fixation for SER lateral malleolar fractures.

METHODS

A prospective randomized controlled trial of 76 patients with unilateral Lauge-Hansen SER lateral malleolar fractures was conducted. The patients were randomly treated either with or without the use of interfragmentary lag screws with precontoured lateral locking plate fixation. Clinical outcomes were assessed using the Olerud-Molander Ankle Score and a visual analog scale for pain. Radiologic outcomes were assessed based on the Kellgren and Lawrence scale score, incongruity of the ankle joint, and type of fracture healing. Sixty-nine patients completed 12 months of follow-up.

RESULTS

There was no significant difference between the 2 groups with regard to clinical outcomes at 3 and 12 months after surgery and radiologic outcomes at 12 months after surgery. All patients in both groups achieved primary bone healing.

CONCLUSION

The results of this study suggest that with precontoured lateral locking plate fixation, the use of interfragmentary lag screw is not essential in the treatment SER lateral malleolar fractures.

LEVEL OF EVIDENCE

Level I, prospective randomized study.

Comparison of three different reduction methods of the ankle mortise in unstable syndesmotic injuries

In order to achieve a clinically satisfying result and to prevent posttraumatic osteoarthritis in the treatment of unstable syndesmotic injuries, anatomically correct reduction is crucial. The objective of the study was to investigate three different reduction methods of the ankle mortise in unstable syndesmotic injuries. In a specimen model with 38 uninjured fresh-frozen lower legs, a complete syndesmotic dissection was performed. The ankle mortise was reduced with either a collinear reduction clamp, a conventional reduction forceps or manually with crossing K-wires. The reduction clamps and the K-wires were placed in a 0°-angle to the leg axis. The clamps were positioned on the posterolateral ridge of the fibula 20 mm proximal to the ankle joint line. A cone beam computed tomography was performed after dissection and after each reduction. Tibio-fibular distances and angles were determined. Despite significant differences in terms of overcompression (0.09–0.33 mm; p = 0.000–0.063) and the slight external rotation (0.29–0.47°; p = 0.014–0.07), the results show a satisfying reduction of the ankle mortise. There were no considerable differences between the reduction methods. It can therefore be concluded that the ankle mortise can be reduced with any of the methods used, but that the positioning and the contact pressure must be considered.

Achilles Tension Mitigates Fibular Malalignment Measured in Cadaveric Studies of Syndesmotic Clamping

BACKGROUND:

Fibular malreduction is becoming a commonly recognized complication of surgical repair of the syndesmosis when a reduction clamp is used. The goal of this work was to determine the interdependent effects of transsyndesmotic reduction clamp position and applied compression force on fibular alignment in a realistic cadaveric preparation of complete syndesmotic injury.

METHODS:

Six through-the-knee cadaveric specimens were CT scanned intact, with the distal syndesmosis fully destabilized, and with 53, 102, and 160 N clamping forces each applied along an anteriorly, centrally, and posteriorly directed transsyndesmotic axis. Testing was repeated incorporating 178 N of Achilles tendon tension using all 3 clamping forces applied along the centrally directed axis. Fibular reduction was automatically quantified from CT scan-generated bony surfaces as rotation of the fibula around the tibia, rotation of the fibula within the incisura, medial/lateral fibular displacement, and anterior/posterior fibular displacement.

RESULTS:

Transsyndesmotic clamping along the anteriorly directed axis resulted in the best reduction quality by all 4 quantified measures. Along the centrally and posteriorly directed axes, progressively greater forces caused significantly greater sagittal plane fibular malreduction. Addition of Achilles tension reduced the magnitude of fibular malreduction and overcompression.

CONCLUSION:

Placing the medial tine of a transsyndesmotic reduction clamp on the anterior medial tibia resulted in the most accurate syndesmotic reduction and provided some protection against overcompression with large reduction clamp forces. Achilles tension appeared to contribute to reduction, decreasing the magnitude of measured malreduction from clamping.

CLINICAL RELEVANCE:

Previous studies estimating fibular malpositioning in cadaveric models that lacked passive muscle tension may have overestimated expected magnitudes of malalignment in patients treated with syndesmotic clamping. However, syndesmotic malreduction, particularly in the sagittal plane, was a real complication of syndesmotic clamping that was reduced by using an anterior position of the medial tine on the tibia.