MRI Assessment of Tendon Graft After Lateral Ankle Ligament Reconstruction: Does Ligamentization Exist?

BACKGROUND: No description exists in the literature about the normal evolution of tendon graft after a lateral ankle ligament (LAL) reconstruction. PURPOSE: To assess the magnetic resonance imaging (MRI) characteristics and the evolution of the tendon graft during different moments in the follow-up after an endoscopic reconstruction of the LAL. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This prospective study included 37 consecutive patients who underwent an endoscopic reconstruction of the LAL with an autograft using the gracilis tendon to treat chronic ankle instability (CAI) resistant to nonoperative treatment (CAI group) and 16 patients without ankle instability (control group). All patients in the CAI group underwent a postoperative assessment at 6, 12, and 24 months using the Karlsson score and MRI examination. Only patients with good and excellent results were included in the study. Graft assessment consisted of qualitative measurements and quantitative evaluations of the reconstructed anterior talofibular ligament (RATFL) and reconstructed calcaneofibular ligament (RCFL), including signal-to-noise quotient (SNQ) and contrast-to-noise quotient (CNQ) measurements in proton density-fat suppressed (PD-FS) and T1-weighted sequences. The analysis of variance test was used to compare the SNQ and the CNQ at different time points for each sequence. RESULTS: The MRI signal at 6 months was increased compared with that of the control group. Next, a significant signal decrease from 6 to 24 months was noted on PD-FS and T1-weighted images. SNQ measurements on PD-FS weighted images for both the RATFL and the RCFL demonstrated a significantly higher signal (P < .01 and P = .01, respectively) at 6 months compared with that of the control group. Subsequently, the signal decreased from 6 to 24 months. Similarly, CNQ measurements on PD-FS weighted images for both the RATFL and the RCFL demonstrated a significantly higher signal (P < .01 and P < .01, respectively) at 6 months compared with that of the control group. Subsequently, the signal decreased from 6 to 24 months. CONCLUSION: The present study demonstrated an evolution of the MRI characteristics, suggesting a process of graft maturation toward ligamentization. This is important for clinical practice, as it suggests an evolution in graft properties and supports the possibility of creating a viable ligament.

Optimal assessment for anterior talofibular ligament injury utilizing stress ultrasound entails internal rotation during plantarflexion.

OBJECTIVES: An optimal load and ankle position for stress ultrasound of the injured anterior talofibular ligament (ATFL) are unknown. The objectives of this study were to compare stress ultrasound and ankle kinematics from a 6 degree-of-freedom (6-DOF) robotic testing system as a reference standard for the evaluation of injured ATFL and suggest cut-off values for ultrasound diagnosis. METHODS: Ten fresh-frozen human cadaveric ankles were used. Loads and ankle positions examined by the 6-DOF robotic testing system were: 40 N anterior load, 1.7 Nm inversion, and 1.7 Nm internal rotation torques at 30° plantarflexion, 15° plantarflexion, and 0° plantarflexion. Bony translations were measured by ultrasound and a robotic testing system under the above conditions. After measuring the intact ankle, ATFL was transected at its fibular attachment under arthroscopy. Correlations between ultrasound and robotic testing systems were calculated with Pearson correlation coefficients. Paired t-tests were performed for comparison of ultrasound measurements of translation between intact and transected ATFL and unloaded and loaded conditions in transected ATFL. RESULTS: Good agreement between ultrasound measurement and that of the robotic testing system was found only in internal rotation at 30° plantarflexion (ICC â€‹= â€‹0.77; 95% confidence interval 0.27-0.94). At 30° plantarflexion, significant differences in ultrasound measurements of translation between intact and transected ATFL (p â€‹< â€‹0.01) were found in response to 1.7 Nm internal rotation torque and nonstress and stress with internal rotation (p â€‹< â€‹0.01) with mean differences of 2.4 â€‹mm and 1.9 â€‹mm, respectively. CONCLUSION: Based on the data of this study, moderate internal rotation and plantarflexion are optimal to evaluate the effects of ATFL injury when clinicians utilize stress ultrasound in patients. LEVEL OF EVIDENCE: III.

Quantitative assessment of anterior talofibular ligament quality in chronic lateral ankle instability using magnetic resonance imaging T2* value.

OBJECTIVE: To determine T2* normal reference values for anterior talofibular ligament (ATFL) and to investigate the feasibility of the quantitative ATFL quality evaluation in chronic lateral ankle instability (CLAI) using T2* values. MATERIALS AND METHODS: This study enrolled 15 patients with CLAI and 30 healthy volunteers. The entire ATFL T2* values from the MRI T2* mapping were measured. The prediction equation (variables: age, height, and weight) in a multiple linear regression model was used to calculate the T2* normal reference value in the healthy group. T2* ratio was defined as the ratio of the actual T2* value of the patient's ATFL to the normal reference value for each patient. A Telos device was used to measure the talar tilt angle (TTA) from the stress radiograph. RESULTS: T2* values of ATFL in the healthy and CLAI groups were 10.82 ± 1.84 ms and 14.36 ± 4.30 ms, respectively, which are significantly higher in the CLAI group (P < 0.05). The prediction equation of the normal reference T2* value was [14.9 + 0.14 × age (years) - 4.7 × height (m) - 0.03 × weight (kg)] (R2 = 0.65, P < 0.0001). A significant positive correlation was found between the T2* ratio and TTA (r = 0.66, P = 0.007). CONCLUSION: MRI T2* values in patients with CLAI were higher than those in healthy participants, and the T2* ratio correlated with TTA, suggesting that T2* values are promising for quantitative assessment of ATFL quality preoperatively.

Statistical shape model-based tibiofibular assessment of syndesmotic ankle lesions using weight-bearing CT.

Forced external rotation is hypothesized as the key mechanism of syndesmotic ankle injuries, inducing a three-dimensional deviation from the normal distal tibiofibular joint (DTFJ) alignment. However, current diagnostic imaging modalities are impeded by a two-dimensional assessment, without considering ligamentous stabilizers. Therefore, our aim is threefold: (1) to construct an articulated statistical shape model of the normal DTFJ with the inclusion of ligamentous morphometry, (2) to investigate the effect of weight-bearing on the DTFJ alignment, and (3) to detect differences in predicted syndesmotic ligament length of patients with syndesmotic lesions with respect to normative data. Training data comprised non-weight-bearing CT scans from asymptomatic controls (N = 76), weight-bearing CT scans from patients with syndesmotic ankle injury (N = 13), and their weight-bearing healthy contralateral side (N = 13). Path and length of the syndesmotic ligaments were predicted using a discrete element model, wrapped around bony contours. Statistical shape model evaluation was based on accuracy, generalization, and compactness. The predicted ligament length in patients with syndesmotic lesions was compared with healthy controls. With respect to the first aim, our presented skeletal shape model described the training data with an accuracy of 0.23 ± 0.028 mm. Mean prediction accuracy of ligament insertions was 0.53 ± 0.12 mm. In accordance with the second aim, our results showed an increased tibiofibular diastasis in healthy ankles after weight-bearing. Concerning our third aim, a statistically significant difference in anterior syndesmotic ligament length was found between ankles with syndesmotic lesions and healthy controls (p = 0.017). There was a significant correlation between the presence of syndesmotic injury and the positional alignment between the distal tibia and fibula (r = 0.873, p < 0,001). Clinical Significance: Statistical shape modeling combined with patient-specific ligament wrapping techniques can facilitate the diagnostic workup of syndesmosic ankle lesions under weight-bearing conditions. In doing so, an increased anterior tibiofibular distance was detected, corresponding to an "anterior open-book injury" of the ankle syndesmosis as a result of anterior inferior tibiofibular ligament elongation/rupture.

The Added Diagnostic Value of the Bright Rim Sign to Conventional MRI Assessment of Anterior Talofibular Ligament Disruption.

RATIONALE AND OBJECTIVES: The bright rim sign (BRS) was used as a reliable indicator of anterior talofibular ligament (ATFL) disruption beside other well-known diagnostic criteria. Although this sign can improve accuracy of conventional magnetic resonance imaging (MRI) in diagnosis of ATFL disruption, it was not adequately discussed in the literature. This study aimed to confirm the added diagnostic value of BRS to conventional MRI assessment of ATFL disruption. MATERIALS AND METHODS: A prospective study included 62 patients (47 males and 15 females; mean age, 36.9 ± 12.1 years; range, 17-52 years) with clinically suspected ATFL disruption. All patients underwent MRI and arthroscopy of ankle. MRI images were evaluated for the presence of ligament disruption sign (LDS) and BRS. The patients were classified into 3 groups: group 1 included patients with acute lateral ankle ligament sprain; group 2 included patients with chronic ankle instability; and group 3 included patients with recurring ankle sprain. The diagnostic value of the BRS was evaluated using arthroscopy as reference standard. RESULTS: The diagnostic value of both signs together increased overall sensitivity in detecting ATFL disruption to 86.7% compared to 60% when considering LDS alone (p < 0.0001). In group 1 and 3, the sensitivity increased when both signs were considered together compared to LDS alone (p = 0.004 and 0.025, respectively). In group 2, there was a trend toward significance in sensitivity when both signs were considered compared to LDS alone (p = 0.08). CONCLUSION: BRS is a very helpful diagnostic sign in assessment of ATFL disruption when considered conjointly with the LDS.

Impact of Torque on Assessment of Syndesmotic Injuries Using Weightbearing Computed Tomography Scans.

BACKGROUND: The diagnosis of subtle injuries to the distal tibiofibular syndesmosis remains elusive. Conventional radiographs miss a large subset of injuries that present without frank diastasis. This study evaluated the impact of torque application on the assessment of syndesmotic injuries when using weightbearing computed tomography (CT) scans. METHODS: Seven pairs of male cadavers (tibia plateau to toe-tip) were included. CT scans with axial load application (85 kg) and with (10 Nm) or without torque to the tibia (corresponding to external rotation of the foot and ankle) were taken during 4 test conditions. First, intact ankles (native) were scanned. Second, 1 specimen from each pair underwent anterior inferior tibiofibular ligament (AITFL) transection (condition 1A), while the contralateral underwent deltoid transection (condition 1B). Third, the lesions were reversed on the same specimens and the remaining intact deltoid or AITFL was transected (condition 2). Finally, the distal tibiofibular interosseous membrane (IOM) was transected in all ankles (condition 3). Measurements were performed to assess the integrity of the distal tibiofibular syndesmosis on digitally reconstructed radiographs (DRRs) and on axial CT scans. RESULTS: Torque impacted DRR and axial CT scan measurements in almost all conditions. The ability to diagnose syndesmotic injuries using axial CT measurements improved when torque was applied. No significant syndesmotic morphological change was observed with or without torque for either isolated AITFL or deltoid ligament transection. DISCUSSION: Torque application had a notable impact on two-dimensional (2-D) measurements used to diagnose syndesmotic injuries for both DRRs and axial CT scans. Because weightbearing conditions allow for standardized positioning of the foot while radiographs or CT scans are taken, the combination of axial load and torque application may be desirable. CLINICAL RELEVANCE: Application of torque to the tibia impacts 2-D measurements and may be useful when diagnosing syndesmotic injuries by DRRs or axial CT images.

Three-Dimensional computed tomography tunnel assessment of allograft anatomic reconstruction in chronic ankle instability: 33 cases.

INTRODUCTION: Although clinical results of anatomic reconstruction using allograft are reportedly good, studies on how accurately the tunnel has been made after surgery are very rare. The purpose of this study was to analyze the postoperative locations of the tunnels through 3-dimensional computed tomography (3D-CT) after anatomic ligament reconstruction and to evaluate its clinical results. HYPOTHESIS: We hypothesized that anatomic lateral ligament reconstruction could lead to excellent results in clinical outcomes by repositioning anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) accurately. MATERIALS AND METHODS: Thirty-three special forces of soldiers who were diagnosed as chronic ankle instability (CAI) were included. Visual analogue scale (VAS), American orthopaedic foot and ankle society (AOFAS) ankle-hind foot functional scores, and Tegner activity scale were comparatively analyzed before the surgery and at final follow-up. The locations of the talar, fibular and calcaneal tunnels were evaluated with 3D-CT taken after the surgery. Talar tilt and anterior drawer displacement were measured on stress radiographs. RESULTS: The mean follow-up period was 26.8±3.6 months. The VAS decreased from 6.9±1.6 to 1.7±1.3, AOFAS ankle-hindfoot functional score increased from 61.3±14.8 to 88.7±9.2, and Tegner activity scale improved from 5.3±1.2 to 6.4±1.3 (p<0.001). Talar tunnel for ATFL was located about68% of the way from the lateral talar process, and fibular tunnels for ATFL and CFL were approximately 52% and 20% of the way from the fibular tip. The calcaneus tunnel was approximately 17mm posterosuperior from the peroneal tubercle on 3D-CT. Talar tilt decreased from 15.8±4.8 to 3.9±2.1 degrees (p<0.001). There were excellent inter-observer agreements for CT evaluation (Kappa values were from 0.83 to 0.92). There was no relapse of lateral instability. DISCUSSION: Anatomic reconstruction of the lateral ligaments using allograft and the interference screw for CAI showed good results in postoperative stability and subjective clinical evaluation by repositioning the location of ATFL and CFL accurately on radiological determination. LEVEL OF EVIDENCE: IV, Case-series.

Clinical and magnetic resonance imaging assessment of anatomical lateral ankle ligament reconstruction: comparison of tendon allograft and autograft.

PURPOSE: To compare the results of anatomical lateral ankle ligament (LAL) reconstruction with tendon allograft and autograft using clinical scores and ultrashort echo time (UTE) sequence of MRI. METHODS: A total of 26 patients with LAL reconstruction were recruited in this study, including 16 using semitendinosus allografts and 10 using semitendinosus autograft. All of them were diagnosed as chronic ankle instability and accepted anatomic reconstruction. The American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson score, and radiological evaluation using MRI UTE scanning were extracted from each patient. The comparative analysis of the clinical assessments and UTE-T2* values were performed between the patients using autografts and allografts. RESULTS: For the allograft group, the mean AOFAS score improved from 69.9 ± 13.3 to 94.8 ± 5.4 (P = 0.000), and the mean Karlsson score improved from 70.3 ± 12.2 to 93.8 ± 5.6 (P = 0.000). For the autograft group, the mean AOFAS score improved from 68.4 ± 10.0 to 94.7 ± 5.0 (P = 0.000), and the mean Karlsson score improved from 64.5 ± 14.4 to 95.0 ± 5.8 (P = 0.000). No significant differences were found between the allograft and autograft neither before (AOFAS P = 0.756, Karlsson P = 0.285) nor after (AOFAS P = 0.957, Karlsson P = 0.574) surgery. While the UTE T2* values in allograft were higher than those of autograft group both in anterior talofibular ligament (8.3 ± 1.0 vs 7.6 ± 1.1 P = 0.027) and intra-tunnel graft (7.8 ± 0.6 vs 7.2 ± 0.8 P = 0.045). CONCLUSION: Both allograft and autograft reconstructions could get an ideal patient satisfaction and clinical functional outcomes at the follow-up. Higher T2* values were found in allograft group which indicated that autograft had some superiorities in respect of revascularization process, collagen structure, water content, and tendon properties.

A new assessment for syndesmosis injury - The 'Chertsey test'.

INTRODUCTION: If a syndesmosis injury is not detected, or not treated appropriately, it can lead to pain and arthritis. Various techniques have been described to look for the presence of a syndemosis injury. If concern is raised regarding malreduction, the most recognised way of checking accuracy of the reduction (of the fibula into the incisura) is bilateral postoperative ankle CT scans. This not only exposes the patient to further radiation, but can normally only be done once the surgery is completed and so if adjustment is needed, this requires a further operation, encompassing further surgical risks. We developed a simple assessment, which both gives accurate intra-operative demonstration of an injury to the syndesmosis and also can check how well the fibula has been reduced (if required), without the need for further radiological investigation or surgical intervention. The objectives were to test how easy it was to perform the test and apply it to a number of different ankle fractures. METHODS: Peri-operatively, 2-4ml of contrast medium was injected into the ankle joint in cases where there was concern about injury to the syndesmosis. If there was a 'positive' test, and a 'blush' of dye leaked into the surrounding soft tissues, then fixation of the syndesmosis was performed (as per the surgeon's preferred technique). After fixation was completed, a further injection of contrast medium was injected to see if the fibular had been anatomically reduced into its incisura. The test was performed on 15 ankles. RESULTS: There were no difficulties in performing the test and no complications reported. The test clearly demonstrated where there had been an injury to the syndesmosis and also confirmed the accurate reduction of the fibula when there had been stabilisation of the syndesmosis. CONCLUSIONS: It has proved to be an easy and reliable adjunct to ankle fixation surgery and may have further indications.

A novel 9-region systematic assessment tool for separated ossicle at the fibular tip effects on lateral ankle ligament complex integrity: a cadaveric study.

PURPOSE: Fibular tip ossicle separation can cause ligament injury leading to chronic lateral ankle instability. A cadaveric study was conducted to preliminarily assess the effects of fibular tip separated ossicle location and size on lateral ankle ligament complex integrity. METHODS: X-ray examinations and dissection of the anterior talofibular and calcaneofibular ligaments were conducted in ten radiographically confirmed normal below-knee cadaveric specimens extracted from donated fresh cadavers. Ossicle and bone fragment location and size were recorded, and distal fibula, articular surface, and adjacent ligament effects were determined by a novel 9-region matrix. RESULTS: Ligament risk varied by region. Anterior talofibular ligament width, perpendicular distance to fibular tip, sagittal width of distal fibula, and coronal width of distal fibula at attachment were 7.45 ± 0.22, 11.75 ± 1.03, 20.56 ± 1.54, and 8.68 ± 0.12 mm, respectively. Sagittal distal fibula and calcaneofibular ligament maximum widths at fibular attachment articular surfaces were 16.81 ± 0.96 and 3.50 ± 0.44 mm, respectively. Anterior talofibular to calcaneofibular ligament distance was 2.35 ± 0.14 mm. Separated ossicles >10 mm in regions 1-3 affected anterior talofibular ligaments, calcaneofibular ligaments, and fibular ankle joints; while those in regions 4, 8, and 7 or 9 affected anterior talofibular or calcaneofibular ligaments or were without impact. CONCLUSIONS: At the fibular tip, separated ossicles sized >10 mm impact collateral ligaments and articular surfaces, while those 5-10 and <5 mm impact anterior talofibular or calcaneofibular ligaments, potentially impairing the lateral ankle ligament complex. Thus, systematic matric-based assessment of ossicle size and location can potentially improve and standardize ankle fracture care.

Total ankle replacement compatible with ligament function produces mobility, good clinical scores, and low complication rates: an early clinical assessment.

BACKGROUND: A three-part ankle replacement was developed to achieve compatibility with the natural ligaments by allowing fibers on the medial and lateral sides to remain isometric during passive motion. Unlike all current prostheses, the new design uses nonanatomically shaped components on the tibia and talus and a fully conforming interposed meniscal bearing. QUESTIONS/PURPOSES: Does this new design restore ankle mobility, improve clinical score, and result in low complication and early revision rates? PATIENTS AND METHODS: We reviewed 51 patients in whom 51 prostheses were implanted in a seven-center trial from July 2003 to July 2006. The mean age of the patients at surgery was 61.5 years (range, 35.1-82.5 years). We used the AOFAS score to assess clinical outcome. We used lateral radiographs to assess function. The minimum followup was 24 months (mean, 30 months; range, 24-48 months). RESULTS: The mean preoperative AOFAS score of 38.5 increased to 76.9, 79.1, 76.4, and 79.0 at 12, 24, 36, and 48 months, respectively. We observed a correlation between meniscal bearing movement on the tibial component (mean, 3.4 mm; range, 2-12 mm) and range of flexion at the replaced ankle (mean, 27.4º; range, 16º-53º). We revised one arthroplasty in the second postoperative year for lateral impingement, providing a 3-year cumulative survival rate of 97% and performed one other secondary operation for hindfoot pain. CONCLUSIONS: These data suggest the new prosthesis can provide short-term restoration of ankle mobility, a good clinical score, and low complication and failure rates. Longer followup with larger numbers is required. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

[Long-term clinical and radiological assessment of talocrural joint stability after acute traumatic injury of ligamentous-capsular apparatus]. / Odlegla ocena kliniczna i radiologiczna stabilnosci stawu skokowo-goleniowego po ostrym urazowym uszkodzeniu aparatu wiezadlowo-torebkowego.

The author presents an assessment of clinical and radiological talocrural joint stability after acute traumatic ankle sprain treated non-operatively. Radiological evaluation of joint stability was performed using a special stand designed by the author. Joint stability was evaluated in both the sagittal and frontal planesusing Zwipp's technique, along with the author's own technique. I degree and II degree lateral and antero-lateral instability were found most often found in the 368 patient series that was examined. Joint instability was recognised more frequently radiologically than clinically.