InternalBrace has Comparable Stiffness and Strength as Tightrope for Lisfranc Fixation

Category: Sports, Biomechanics Introduction/Purpose: Lisfranc injuries are characterized by disruption between the medial cuneiform and base of the second metatarsal. Conventional interfragmentary screws decreases the amount of diastasis, however is believed to decrease the natural physiological movement of the joint compared to suture button (Tightrope, Arthrex, Inc., Naples, FL). The InternalBrace (IB, Arthrex, Inc., Naples, FL) allows physiologic movement and collagen ingrowth, while also decreasing iatrogenic bone loss. It also prevents erosion of the suture button into the medial cuneiform and prevents irritation of the tibialis anterior tendon. We hypothesized that there was no significant difference in the mechanical properties of these three constructs. Methods: Three groups of 10 sawbone models were used in this study. Two fourth generation 20 mm cylinder sawbones with open cell foam were fixed together with either a 3.5 mm conventional screw, mini Tightrope or IB with a curved button and 4.75 mm biotenodesis screw. Sawbone constructs were held in a mechanical testing system (Model 809, MTS Systems Corp, Minneapolis MN) using custom fixtures. Constructs were loaded in axial tension at 0.5mm/sec until failure. Load-displacement data were plotted for each test. Yield, stiffness, ultimate strength (US), yield energy, post-yield energy and ultimate strength energy were calculated Additionally, the load and energy to 0.5 mm, 1.0 mm and 1.5 mm of displacement were captured to relate strength at clinically relevant displacements. The residuals of an ANOVA on all mechanical testing results were not normally distributed. Therefore non-parametric comparison was used to compare fixation types (Proc NPAR1WAY, SAS 9.4, SAS Institute). Results: Compared to IB, the screw demonstrated greater stiffness, yield load and energy, and ultimate load and energy, with smaller yield, ultimate and failure displacement. When comparing the Tightrope and IB, there was no difference in stiffness (p=0.82), although the Tightrope performed greater in terms of having a larger yield load, energy and displacement, a larger ultimate strength load, energy and displacement, and a larger failure load, energy and displacement. When assessing the load at various distances of displacement, there was no significant difference between the load at 0.5 mm displacement (p=0.5, Figure 1). At greater displacement, the load was greater in the Tightrope than the IB (Figure 1). Conclusion: In this study, IB has shown proper stiffness and strength for fixation of ligamentous lisfranc injury. However, if a diastasis of >0.5 mm is evident, concerns for a clinical failure should be examined. This is the first study examining the use of an IB for treatment of a ligamentous lisfranc injury. The data supports its current clinical indications and further studies in cadaveric models are recommended.

Download Full-text

Technique Tip

Foot & Ankle Specialist ◽

10.1177/1938640016677812 ◽

2016 ◽

Vol 10 (2) ◽

pp. 149-151

Author(s):

Gregory R. Waryasz ◽

Stephen Marcaccio ◽

Joseph A. Gil

Keyword(s):

Anterior Cruciate Ligament ◽

Cruciate Ligament ◽

Screw Placement ◽

Lisfranc Joint ◽

Lisfranc Injury ◽

Levels Of Evidence ◽

Suture Button ◽

Medial Cuneiform ◽

Second Metatarsal ◽

Anterior Cruciate

Lisfranc injury fixation or arthrodesis typically involves the reduction and fixation of several tarsometatarsal joints with either screws or a plate and screw constructs. A successful fixation or arthrodesis of the Lisfranc joint requires proper screw placement from the medial cuneiform to the base of the second metatarsal. This is typically done free-hand; however, we describe use of an anterior cruciate ligament guide to help maintain reduction and assist with drill trajectory for more accurate screw or suture button construct placement. Levels of Evidence: Level V

Download Full-text

In Vitro Testing of 2 Adjustable-Loop Cortical Suspensory Fixation Systems Versus Interference Screw for Anterior Cruciate Ligament Reconstruction

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211031652 ◽

2021 ◽

Vol 9 (9) ◽

pp. 232596712110316

Author(s):

Gerardo L. Garcés ◽

Oscar Martel ◽

Alejandro Yánez ◽

Ignacio Manchado-Herrera ◽

Luci M. Motta

Keyword(s):

Anterior Cruciate Ligament ◽

Acl Reconstruction ◽

Failure Load ◽

Cruciate Ligament ◽

Interference Screw ◽

Yield Load ◽

Ultimate Failure Load ◽

Significant Difference ◽

Ultimate Failure ◽

Anterior Cruciate

Background: It is not clear whether the mechanical strength of adjustable-loop suspension devices (ALDs) in anterior cruciate ligament (ACL) reconstruction is device dependent and if these constructs are different from those of an interference screw. Purpose: To compare the biomechanical differences of 2 types of ALDs versus an interference screw. Study Design: Controlled laboratory study. Methods: ACL reconstruction was performed on porcine femurs and bovine extensor tendons with 3 types of fixation devices: interference screw, UltraButton (UB) ALD, and TightRope (TR) ALD (n = 10 for each). In addition to specimen testing, isolated testing of the 2 ALDs was performed. The loading protocol consisted of 3 stages: preload (static 150 N load for 5 minutes), cyclic load (50-250 N at 1 Hz for 1000 cycles), and load to failure (crosshead speed 50 mm/min). Displacement at different cycles, ultimate failure load, yield load, stiffness, and failure mode were recorded. Results: In specimen testing, displacement of the ALDs at the 1000th cycle was similar (3.42 ± 1.34 mm for TR and 3.39 ± 0.92 mm for UB), but both were significantly lower than that of the interference screw (7.54 ± 3.18 mm) ( P < .001 for both). The yield load of the UB (547 ± 173 N) was higher than that of the TR (420 ± 72 N) ( P = .033) or the interference screw (386 ± 51 N; P = .013), with no significant difference between the latter 2. In isolated device testing, the ultimate failure load of the TR (862 ± 64 N) was significantly lower than that of the UB (1879 ± 126 N) ( P < .001). Conclusion: Both ALDs showed significantly less displacement in cyclic loading at ultimate failure than the interference screw. The yield load of the UB was significantly higher than that of the other 2. The ultimate failure occurred at a significantly higher load for UB than it did for TR in isolated device testing. Clinical Relevance: Both UB and TR provided stronger fixation than an interference screw. Although difficult to assess, intrinsic differences in the mechanical properties of these ALDs may affect clinical outcomes.

Download Full-text

InternalBrace Has Biomechanical Properties Comparable to Suture Button but Less Rigid than Screw in Ligamentous Lisfranc Model

Foot & Ankle Orthopaedics ◽

10.1177/2473011419s00221 ◽

2019 ◽

Vol 4 (4) ◽

pp. 2473011419S0022

Author(s):

Justin Hopkins ◽

Kevin Nguyen ◽

Nasser Heyrani ◽

Trevor Shelton ◽

Christopher Kreulen ◽

...

Keyword(s):

Soft Tissue ◽

Ultimate Strength ◽

Cartilage Damage ◽

Biomechanical Properties ◽

Early Weight Bearing ◽

Suture Button ◽

Axial Tension ◽

Significant Difference ◽

Potential Benefits ◽

Lisfranc Injuries

Category: Midfoot/Forefoot, Trauma Introduction/Purpose: Lisfranc injuries occurring between the medial cuneiform and base of the 2nd metatarsal require anatomic fixation. Suture button and screws are standard techniques for fixation, but the screw may decrease physiologic motion, whereas suture buttons may cause increased soft tissue irritation and iatrogenic cartilage damage. Potential benefits of the InternalBrace include physiologic motion, decreased iatrogenic damage, collagen ingrowth, limited bony erosion and decreased soft tissue irritation. In light of these potential benefits, no studies have investigated the biomechanical properties of the InternalBrace in a Lisfranc injury model. However, it is unknown whether there is significant difference in the biomechanical properties of the IB compared to the screw, or SB during load to failure, and cyclical loading. Methods: Three groups of sawbones were fixed together with either a 3.5 mm screw, SB, or IB, composed of a curved button, fibertape, and 4.75 mm biotenodesis screw. Sawbone constructs were held in a mechanical testing system (Model 809, MTS Systems Corp, Minneapolis MN). The first three groups of 10 were loaded in axial tension at 0.5mm/sec until failure to determine load-displacement data. Yield, stiffness, ultimate strength (US), yield energy, post-yield energy and ultimate strength energy were calculated. Three more groups of 8 constructs were loaded in-vitro at cyclical physiologic loads until displacement of 1.5 mm occurred. Constructs were first loaded for 10,000 cycles at 69 N (estimate for 50% body weight or assisted walking). Surviving specimens were loaded at 138 N (normal walk) for an additional 10,000 cycles and then 207 N (jog) for an additional 10,000 cycles. Displacement was recorded. The biomechanical properties were then compared between groups. Results: When loaded in axial tension at 0.5mm/sec until failure, the screw was found to be the stiffest construct (2,240 N/mm), while the InternalBrace (200 N/mm) was stiffer than the suture button (133 N/mm). Qualitatively, the InternalBrace was also found to hold load more consistently and for larger displacement prior to failure when compared to the suture button. Cyclic loading was performed with 10,000 cycles of 69 N, 138 N, and 207 N. The screw had the greatest resistance to fatigue. The InternalBrace maintained stiffness as well or better than the suture button, but the fatigue life was shorter than that of the suture button. Conclusion: To our knowledge, the biomechanical properties of the IB have not been compared to screw and SB for ligamentous lisfranc injuries. This study gives valuable information about the mechanical integrity of InternalBrace and supports continued use. However, further studies are warranted before making conclusions regarding early weight bearing.

Download Full-text

A biomechanical comparison of external skeletal fixation and plating for the stabilization of ilial osteotomies in dogs

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-06-10-0072 ◽

2008 ◽

Vol 21 (04) ◽

pp. 349-357 ◽

Cited By ~ 13

Author(s):

D. Lewis ◽

A. Cross ◽

N. Fitzpatrick

Keyword(s):

External Fixator ◽

Failure Load ◽

Bending Stiffness ◽

Materials Testing ◽

External Fixators ◽

Displacement Curve ◽

Steel Sphere ◽

Yield Load ◽

Significant Difference ◽

Load Displacement

SummaryThis in vitro study compares the biomechanical properties of two methods of ilial fracture repair in dogs. Ten pelves were harvested from skeletally mature mixed breed dogs weighing 20–27 kg and bilateral oblique ilial body osteotomies were created. One hemipelvis from each dog was stabilized with a 2.7 mm plate and screws and the contralateral hemipelvis was stabilized with a five pin linear external fixator construct. Each hemipelvis was mounted at an angle of 30° to an actuator platform, such that the acetabulum was centrally loaded by a steel sphere attached to the load cell of a servohydraulic materials testing machine. The construct was loaded at a constant rate of 20 mm/min. A load/displacement curve was generated for each hemipelvis by plotting the sustained load against the actuator movement. The stiffness, yield load and failure load for each hemipelvis were determined from the load/displacement curve. Bending stiffness was defined as the slope of the load/displacement curve from 100 N to yield load. The mode of failure was determined by observations made during testing and gross inspection of each specimen. The mean construct stiffness, yield load and failure load were compared between stabilization groups using a Student’s paired t-test with statistical significance set at p>0.05. Nine out of 10 of the hemipelves that were stabilized by plates and screws failed catastrophically by fracture through the caudal screw holes and nine out of 10 of the hemipelves that were stabilized using an external fixator failed by fracture of the ischium in the region supported by the mounting roller, propagating through the most caudal ischial pin. There was not any significant difference (P = 0.22) in bending stiffness between stabilization techniques, but yield (1467 N vs 2620 N; P = 0.04) and failure (1918 N vs 2687 N; P = 0.002) loads were significantly greater for hemipelves stabilized with external fixators.

Download Full-text

A COMPARATIVE BIOMECHANICAL STUDY OF THE LOOPED SQUARE SLIP KNOT AND THE SIMPLE SURGICAL KNOT

Hand Surgery ◽

10.1142/s0218810406003152 ◽

2006 ◽

Vol 11 (01n02) ◽

pp. 93-99 ◽

Cited By ~ 1

Author(s):

Surut Jianmongkol ◽

Geoffrey Hooper ◽

Weerachai Kowsuwon ◽

Tala Thammaroj

Keyword(s):

Ultimate Strength ◽

Hand Surgery ◽

Biomechanical Properties ◽

Biomechanical Study ◽

Skin Closure ◽

Significant Difference ◽

Mode Of Failure ◽

Repetitive Loading ◽

Slip Knot

The looped square slip knot was introduced as a technique for skin closure to avoid the use of sharp instruments in suture removal after hand surgery. We compared the biomechanical properties of this knot with the simple surgical square knot. The ultimate strength of the looped square slip knot was significantly (p = 0.015) higher than the simple surgical knot. There was no significant difference between the two knots in mode of failure. Knot slippage or suture breakage did not occur in any samples when testing security by repetitive loading. Therefore, the looped square slip knot is a safe and convenient alternative to the two-throw surgical knot for use in hand surgery.

Download Full-text

Surgical Anatomy of the Medial Cuneiform (Cotton) Osteotomy

Foot & Ankle Orthopaedics ◽

10.1177/2473011419885344 ◽

2019 ◽

Vol 4 (4) ◽

pp. 247301141988534

Author(s):

Baofu Wei ◽

Brian C. Lau ◽

Annunziato Amendola

Keyword(s):

Tilt Angle ◽

Tibialis Anterior ◽

Articular Surface ◽

Wedge Osteotomy ◽

Opening Wedge ◽

Small Branch ◽

Medial Cuneiform ◽

Significant Difference ◽

Oblique Incision ◽

Distal Articular Surface

Background: The Cotton osteotomy, or dorsal-opening wedge osteotomy of the medial cuneiform (MC), is used to address medial column alignment to restore the static-triangle of support. There are many described techniques regarding the incision and osteotomy. Successful completion of the osteotomy requires knowledge of the anatomy, particularly the location of the medial dorsal cutaneous nerve (MDCN). This study describes the relationship between MDCN, tibialis anterior, extensor-hallucis-longus tendon, and ligamentous attachments to the MC. A technique to determine a safe location for the osteotomy is also described. Methods: Twelve fresh-frozen adult foot specimens were used for this study (7 male and 5 female). The MDCN and its branches were dissected and its relationship with the MC was documented. Osteotomy tilt angle and relationship to structures around the MC were measured. Results: MDCN traveled medially and distally over the dorsum of the MC, and a small branch to the MC was observed. The tilt angle was 80.1 ±1.4 degrees. There was no significant difference between the distance from the distal-articular surface to the midline of the cuneiform and to the interosseous ligament ( P = .69), or between the distance from the distal-articular surface to the second tarsometatarsal joint and to the origin of the Lisfranc ligament ( P = .12). Conclusions: The dorsal-medial-oblique incision effectively protected MDCN and the MC. We believe the osteotomy should be performed in the safe zone to maintain the stability of the opening wedge. Clinical relevance: The dorsal-medial-oblique incision could reduce the risk of injury to the MDCN and the tibialis-anterior tendon.

Download Full-text

Undeveloped semiconic posterosuperior ligament and susceptibility to avulsion of the C-7 spinal nerve in Erb palsy

Journal of Neurosurgery Pediatrics ◽

10.3171/2011.3.peds1159 ◽

2011 ◽

Vol 7 (6) ◽

pp. 676-680 ◽

Cited By ~ 1

Author(s):

Yi-gang Huang ◽

Liang Chen ◽

Yu-dong Gu ◽

Guang-rong Yu

Keyword(s):

Failure Load ◽

Transverse Process ◽

Biomechanical Properties ◽

Spinal Nerve ◽

Spinal Nerves ◽

Honestly Significant Difference ◽

Significant Difference ◽

Tukey Honestly Significant Difference ◽

Tension Testing ◽

Histological Characteristics

Object In Erb palsy, the C-7 spinal nerve has been found to be more subject to avulsion than the C-5 and C-6 spinal nerves. This study investigated the morphological and biomechanical characteristics of the semiconic posterosuperior ligaments (SPLs) at the C-5, C-6, and C-7 spinal nerves in neonates. Methods Twenty-four brachial plexuses from 12 fresh neonate cadavers were used in this study. In 12 brachial plexuses from 6 cadavers, the following studies were performed with respect to the SPLs at the C-5, C-6, and C-7 spinal nerves: gross observation of morphological and histological characteristics; measurement of length, thickness, and width; and a semiquantitative analysis of collagen. In the other 6 cadavers, biomechanical tension testing was performed bilaterally on the C5–7 SPLs to assess the tensile strength of the ligaments. Results The C5–7 spinal nerves are fixed to the transverse process through the SPL, a structure not observed at the C-8 and T-1 spinal nerves. Except for the width of the SPL insertion on the spinal nerve, which was found to increase gradually from C-5 to C-7, there was no statistically significant difference in the dimensions of the C-5, C-6, and C-7 SPLs. The sectional area percentage of collagen was 51% ± 10% in SPLs for C-5, 51% ± 11% for C-6, and 41% ± 10% for C-7; and this percentage was significantly lower in SPLs for C-7 than for C-5 or C-6 (1-way ANOVA, F = 4.3, p = 0.02; Tukey honestly significant difference test, p = 0.04 and 0.04, respectively). Sharpey fibers were observed at the transverse process origin of the SPL at C-5 and C-6 but not at C-7. Biomechanical tension testing showed that the mean failure load was 6.6 ± 0.9 N for the C-5 SPL, 6.4 ± 1.0 N for the C-6 SPL, and 5.4 ± 0.9 N for the C-7 SPL, and the failure load was significantly lower in SPLs at C-7 than in those at C-5 or C-6 (1-way ANOVA, F = 5.1, p = 0.01; Tukey honestly significant difference, p = 0.01 and 0.048, respectively). Nine of 12 C-7 SPLs failed at their origin from the transverse process, while only 4 of 12 C-5 SPLs and 3 of 12 C-6 SPLs failed at the origin site. Conclusions These findings suggest that the lower density of collagen and absence of Sharpey fibers decrease the biomechanical properties of the C-7 SPL, and this may account for the higher frequency of avulsion of the C-7 spinal nerve (in comparison with the C-5 or C-6 nerve) in Erb palsy.

Download Full-text

Effect of the additional first ray osteotomy on hindfoot alignment after calcaneal osteotomy for the correction of mild-to-moderate adult type pes plano-valgus

Journal of Orthopaedic Surgery ◽

10.1177/2309499016684747 ◽

2017 ◽

Vol 25 (1) ◽

pp. 230949901668474

Author(s):

Jun Young Choi ◽

Seong Mu Cha ◽

Ji Woong Yeom ◽

Jin Soo Suh

Keyword(s):

Wedge Osteotomy ◽

Opening Wedge ◽

Adult Type ◽

Hindfoot Alignment ◽

Calcaneal Osteotomy ◽

Medial Cuneiform ◽

Significant Difference ◽

First Ray ◽

Pes Plano Valgus

Purpose: To determine the effect of the additional first ray osteotomy on hindfoot alignment for the correction of pes plano-valgus. Methods: Data obtained from 37 consecutive patients recruited from 2006 to 2014 who underwent medial displacement calcaneal osteotomy (MDCO) alone (group H) or MDCO followed by medial cuneiform opening wedge osteotomy (MCOWO) (group HF) with a minimum 1-year follow-up were reviewed retrospectively. The mean follow-up periods were 34 and 32 months. Results: Degree of decrease of Talonavicular coverage angle (TNCA) via surgery or postoperative TNCA on standing foot AP radiographs were not significantly different between group H and HF ( p = 0.287). The calcaneal pitch angle and medial cuneiform height on the standing foot lateral radiographs was significantly increased after operation in group HF ( p = 0.01), there was a significant difference with group H as well ( p = 0.033). In group HF, the Meary’s angle was significantly decreased after operation, a significant difference compared to group H ( p = 0.009). Hindfoot alignment angle on the hindfoot alignment view was decreased after operation in both groups but was not significantly different between both groups ( p = 0.410). Hindfoot alignment ratio was also increased after the operation in both groups, but was not different between two groups ( p = 0.783). Conclusion: The additional first ray osteotomy using MCOWO had no correctional power for hindfoot correction, although it caused improvement in some radiographic parameters.

Download Full-text

Evaluation of Reduction Accuracy of Suture-Button and Screw Fixation Techniques for Syndesmotic Injuries

Foot & Ankle International ◽

10.1177/1071100716661221 ◽

2016 ◽

Vol 37 (12) ◽

pp. 1317-1325 ◽

Cited By ~ 32

Author(s):

Onur Kocadal ◽

Mehmet Yucel ◽

Murad Pepe ◽

Ertugrul Aksahin ◽

Cem Nuri Aktekin

Keyword(s):

Screw Fixation ◽

Ct Scans ◽

Functional Evaluation ◽

Level Of Evidence ◽

Cross Sectional ◽

Suture Button ◽

Fixation Group ◽

Significant Difference ◽

The Mean

Background: Among the most important predictors of functional results of treatment of syndesmotic injuries is the accurate restoration of the syndesmotic space. The purpose of this study was to investigate the reduction performance of screw fixation and suture-button techniques using images obtained from computed tomography (CT) scans. Methods: Patients at or below 65 years who were treated with screw or suture-button fixation for syndesmotic injuries accompanying ankle fractures between January 2012 and March 2015 were retrospectively reviewed in our regional trauma unit. A total of 52 patients were included in the present study. Fixation was performed with syndesmotic screws in 26 patients and suture-button fixation in 26 patients. The patients were divided into 2 groups according to the fixation methods. Postoperative CT scans were used for radiologic evaluation. Four parameters (anteroposterior reduction, rotational reduction, the cross-sectional syndesmotic area, and the distal tibiofibular volumes) were taken into consideration for the radiologic assessment. Functional evaluation of patients was done using the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale at the final follow-up. The mean follow-up period was 16.7 ± 11.0 months, and the mean age was 44.1 ± 13.2. Results: There was a statistically significant decrease in the degree of fibular rotation ( P = .03) and an increase in the upper syndesmotic area ( P = .006) compared with the contralateral limb in the screw fixation group. In the suture-button fixation group, there was a statistically significant increase in the lower syndesmotic area ( P = .02) and distal tibiofibular volumes ( P = .04) compared with the contralateral limbs. The mean AOFAS scores were 88.4 ± 9.2 and 86.1 ± 14.0 in the suture-button fixation and screw fixation group, respectively. There was no statistically significant difference in the functional ankle joint scores between the groups. Conclusion: Although the functional outcomes were similar, the restoration of the fibular rotation in the treatment of syndesmotic injuries by screw fixation was troublesome and the volume of the distal tibiofibular space increased with the suture-button fixation technique. Level of Evidence: Level III, retrospective comparative study.

Download Full-text

Restoration of Tibiofibular Kinematics with a Tricortical Screw or Suture Button Fixation After Syndesmotic Ankle Injuries

Foot & Ankle Orthopaedics ◽

10.1177/2473011417s000063 ◽

2017 ◽

Vol 2 (3) ◽

pp. 2473011417S0000

Author(s):

Conor Murphy ◽

Thomas Pfeiffer ◽

Jason Zlotnicki ◽

Volker Musahl ◽

Richard Debski ◽

...

Keyword(s):

Screw Fixation ◽

External Rotation ◽

Tracking System ◽

Optical Tracking ◽

Ankle Injuries ◽

Suture Button ◽

Tibiofibular Ligament ◽

Cortical Screw ◽

Significant Difference ◽

Posterior Translation

Category: Ankle, Sports, Trauma Introduction/Purpose: Anterior inferior tibiofibular ligament (AITFL), Posterior inferior tibiofibular ligament (PITFL) and Interosseous membrane (IOM) disruption is a predictive measure of residual symptoms after ankle injury. In unstable injuries, the syndesmosis is treated operatively with cortical screw fixation or a suture button apparatus. Biomechanical analyses of suture button versus cortical screw fixation methods show contradicting results regarding suture button integrity and maintenance of fixation. The objective of this study is to quantify tibiofibular joint motion in syndesmotic screw and suture button fixation models compared to the intact ankle. Methods: Five fresh-frozen human cadaveric specimens (mean age 58 yrs.; range 38-73 yrs.) were tested using a 6-degree-of- freedom robotic testing system. The tibia and calcaneus were rigidly fixed to the robotic manipulator and the subtalar joint was fused. The full fibular length was maintained and fibular motion was unconstrained. Fibular motion with respect to the tibia was tracked by a 3D optical tracking system. A 5 Nm external rotation moment and 5 Nm inversion moment were applied to the ankle at 0°, 15°, and 30° plantarflexion and 10° dorsiflexion. Outcome variables included fibular medial-lateral (ML) translation, anterior-posterior (AP) translation, and external rotation (ER) in the following states: 1) intact ankle, 2) AITFL transected, 3) PITFL and IOM transected, 4) 3.5 mm cannulated tricortical screw fixation, 5) suture button fixation. An ANOVA with a post-hoc Tukey analysis was performed for statistical analysis (*p<0.05). Results: Significant differences in fibular motion were only during the inversion moment. Fibular posterior translation was significantly higher with complete syndesmosis injury compared to the intact ankle at 0°, 15°, and 30° plantarflexion and the tricortical screw at 15° and 30°. Significantly higher fibular posterior translation was observed with the suture button compared to the intact ankle at 15° and 30 plantarflexion and to the tricortical screw at 15°. ER was significantly increased with complete injury compared to the tricortical screw at 0° and 30° plantarflexion. The suture button demonstrated significantly greater ER at 0° plantarflexion and 10° dorsiflexion compared to the intact ankle. The only significant difference in ML translation exists between the tricortical screw and complete injury at 30° plantarflexion. Conclusion: The suture button did not restore physiologic motion of the syndesmosis. It only restored fibular ML translation. Significant differences in AP translation and ER persisted compared to the intact ankle. The tricortical screw restored fibular motion in all planes. No significant differences were observed compared to the intact ankle. These findings are consistent with previous studies. This study utilized a novel setup to measure unconstrained motion in a full length, intact fibula. Physicians should evaluate AP translation and ER as critical fibular motions when reconstructing the syndesmosis with suture button fixation.

Download Full-text