Do We Need Extensor Retinacular Enhancement on Broström Lateral Ankle Repair? A Systematic Review and Meta-analysis

Aims This meta-analysis compared inferior extensor retinaculum (IER) enhancement in Broström-Gould procedure and anatomical Broström repair. We aim to evaluate functional ankle score (American Orthopaedic Foot & Ankle Society (AOFAS) score, Karlsson score), talar tilt, talar anterior translation, and complications between both groups. Methods A comprehensive systematic literature search was carried out using Wiley Library, Scopus, Pubmed, ScienceDirect, and EuropePMC databases from inception up until 19 December 2020. While the intervention was IER enhancement, the control was those without IER enhancement. The primary outcome was the functional ankle score (AOFAS and Karlsson score). The secondary outcomes were talar tilt, talar anterior translation, and other complications. Results There was a total of 298 patients from 7 studies included in this systematic review and meta-analysis. IER enhancement was associated with lower AOFAS (mean difference -1.115 [-2.197, -0.033], p=0.043; I2: 0%) during follow-up. Lower Karlsson score was observed in the IER enhancement group (mean difference -2.004 [-3.442, -0.567], p=0.006; I2: 3.71%) during follow-up. Talar tilt (mean difference -0.145 degree [-0.436, 0.146], p=0.329; I2: 0%) and anterior displacement (mean difference -0.109 mm [-0.096, 0.314], p=0.299; I2: 0%) in the two groups were similar on follow-up. The complications were similar in both groups (OR 0.87 [0.40, 1.89], p=0.719; I2: 0%). Meta-regression analysis indicates that the association between IER and AOFAS was not affected by age (p=0.927) and male gender (p=0.930). Conclusion This meta-analysis showed that ATFL repair with non-IER enhancement was non-inferior compared to those with IER enhancement.

Kinematic Analysis of Lateral Meniscal Oblique Radial Tears in the Anterior Cruciate Ligament–Deficient Knee

Background: Lateral meniscal oblique radial tears (LMORT) occur frequently in conjunction with anterior cruciate ligament (ACL) disruption and are anatomically distinct from meniscus root tears. Hypothesis/Purpose: The purpose of this study was to characterize the effects of LMORT types 3 (LMORT3) and 4 (LMORT4) lesions on joint stability and meniscal extrusion in ACL-deficient knees. Our hypothesis was that both lesions would promote significant increases in anterior translation and meniscal extrusion, with the LMORT4 lesion having a greater effect. Study Design: Controlled laboratory study. Methods: Two matched pairs of cadaveric knees (n = 4) were used to optimize the testing sequence. Additional cadaveric knees with LMORT3 (n = 8) and LMORT4 (n = 8) lesions created after ACL transection underwent robotic kinematic testing for anterior drawer and pivot-shift simulations with associated ultrasound-measured meniscal extrusion at clinically relevant knee flexion angles. Results: Optimization testing showed no differences on the effect of LMORT4 lesions for anterior translation and lateral meniscal extrusion with ACL-intact versus ACL-deficient knees. ACL deficiency and LMORT3 and LMORT4 lesions with ACL deficiency were associated with significantly greater anterior translation compared with ACL-intact state for both anterior drawer and pivot-shift testing at all flexion angles ( P < .001). ACL deficiency with either LMORT3 or LMORT4 lesion was associated with significantly greater anterior translation than was ACL deficiency only ( P < .005) for anterior drawer testing at 90° of flexion. Meniscal extrusion was greater with LMORT3 and LMORT4 lesions compared with ACL deficiency only ( P < .05) for anterior drawer at 60° of flexion and for pivot shift at 15° of flexion. The LMORT4 lesion demonstrated increased anterior translation for anterior drawer ( P = .003) at 60° of flexion (12%) as well as for pivot shift at 15° of flexion (7%) and 30° of flexion (13%) ( P < .005) compared with ACL deficiency only. Conclusion: In this cadaveric model, the addition of an LMORT3 or LMORT4 lesion increased anterior laxity for both the anterior drawer and the pivot shift when compared with an isolated ACL tear. Lateral meniscal extrusion was also exacerbated by these LMORT lesions. Clinical Relevance: LMORT lesions, distinct from meniscus root tears, occur frequently in conjunction with ACL tears. This study characterized the biomechanical consequences of LMORT3 and LMORT4 lesions on joint stability and meniscal function, highlighting the importance of diagnosing and treating LMORT lesions at the time of ACL reconstruction.

Assessment of paradoxical anterior translation in a CR total knee prosthesis coupling dynamic RSA and FE techniques

Purpose The study aims were to assess the kinematic data, Internal-External (IE) rotation, and Antero-Posterior (AP) translation of the contact points between the femoral condyles and polyethylene insert and to develop a combined dynamic RSA-FE (Radiostereometric – Finite Element) model that gives results congruent with the literature. Methods A cohort of 15 patients who underwent cemented cruciate-retaining highly congruent mobile-bearing total knee arthroplasty were analyzed during a sit-to-stand motor task. The kinematical data from Dynamic RSA were used as input for a patient-specific FE model to calculate condylar contact points between the femoral component and polyethylene insert. Results The femoral component showed an overall range about 4 mm of AP translation during the whole motor task, and the majority of the movement was after 40° of flexion. Concerning the IE rotation, the femoral component started from an externally rotate position (− 6.7 ± 10°) at 80° of flexion and performed an internal rotation during the entire motor task. The overall range of the IE rotation was 8.2°. Conclusions During the sit to stand, a slight anterior translation from 40° to 0° of flexion of the femoral component with respect to polyethylene insert, which could represent a paradoxical anterior translation. Despite a paradoxical anterior femoral translation was detected, the implants were found to be stable. Dynamic RSA and FE combined technique could provide information about prosthetic component’s stress and strain distribution and the influence of the different designs during the movement.

LCL IN A SINGLE CORONAL SLICE – A NOVEL SIGN FOR IDENTIFYING ACL DEFICIENT PATIENTS AND PREDICTING RISK OF FUTURE GRAFT FAILURE

Background: The ACL deficient knee is predisposed to anterior translation and internal rotation of the tibia. Hypothesis/Purpose: To show that knee deformity in an ACL deficient knee will produce a more vertical orientation of the lateral collateral ligament (LCL), allowing for the entire length of the LCL to be visualized on a single coronal slice (coronal LCL sign) on MRI, and that this sign is indicative of a greater risk for graft failure after ACL reconstruction. Methods: Charts were retrospectively reviewed to create 3 separate cohorts: normal ACL and no pathology involving the collateral ligaments (control cohort), ACL reconstruction without evidence for graft rupture, and ACL reconstruction with graft failure. Tibial translation and femorotibial rotation were measured on MRI, and posterior tibial slope was measured on lateral knee radiographs. Imaging was reviewed for the presence of the coronal LCL sign. Results: Deficient ACL (n=153) compared with intact ACL (n=70) was associated with significantly greater displacement regarding anterior translation (5.8mm internal rotation vs 0.3mm external rotation, p<0.001, respectively) and internal rotation (5.2 degrees vs. -2.4 degrees, p<0.001, respectively). The coronal LCL sign was present in a greater percentage of ACL deficient patients than intact ACL controls (68.6% vs. 18.6%, p<0.001, respectively) and associated with greater anterior tibial translation (7.2mm vs. 0.2mm vs., p<0.001) and internal tibial rotation (7.5 degrees vs 2.4 degrees, p=0.074). Multivariate analysis revealed the coronal LCL sign was significantly associated with an ACL tear (OR 12.8, p<0.001). Of the 153 ACL deficient cohort, 114 had no graft failure patients and 39 experienced graft failure. Mean follow-up time was 3.5 years (2 – 9.4 years). Coronal LCL sign was associated with graft failure (p=0.013), with an odds ratio of 4.3 for graft failure (p=0.003). Comparison of pre- and post-ACL reconstruction MRI in the graft failure cohort demonstrated reduced internal rotation, p= 0.00, but no change in coronal LCL sign (p=0.922). Conclusion: Our study shows that the coronal LCL sign correlates with the presence of an ACL tear and functions as a surrogate for the extent of axial and sagittal deformity. Further, we show that tibia internal rotation and posterior slope are independent predictors of ACL graft failure in adolescents. Whereas, the value of internal rotation could be improved with ACL reconstruction, the presence of the coronal LCL sign persisted over time and was predictive of graft rupture (without the need to make measurements or memorize values of significant risk). [Table: see text][Figure: see text]

Evaluation of the Intact Anterior Talofibular and Calcaneofibular Ligaments, Injuries, and Repairs With and Without Augmentation: A Biomechanical Robotic Study

Background: Acute ankle sprains are common injuries. The anterior talofibular (ATFL) and calcaneofibular ligaments (CFL) are the most injured lateral structures. However, controversy exists on the optimal surgical treatment when the injury is both acute and severe or becomes chronic and unstable. Studies have evaluated the biomechanics of these ligaments, but no studies have robotically evaluated injury effects and surgical treatment of ATFL or ATFL and CFL injuries. Purpose: To quantitatively evaluate biomechanical effects of ATFL and CFL lesions, ATFL repair, ATFL and CFL repair, and augmentation of ATFL on ankle stability. Study Design: Controlled laboratory study. Methods: Ten nonpaired cadaveric ankles were tested using a 6 degrees of freedom robot. Each ankle underwent testing in the following states sequentially: (1) intact, (2) ATFL cut, (3) CFL cut, (4) ATFL repair + CFL cut, (5) ATFL repair + CFL repair, and (6) ATFL repair with augmentation with suture tape + CFL repair. Testing included 88 N anterior drawer and 5 N·m varus talar tilt tests at 0° and 30° of plantarflexion, and 88 N Cotton test at 0° of plantarflexion. Results: After all surgical treatments ankles still had increased laxity compared with intact state testing, except after augmented ATFL repair + CFL repair in anterior drawer testing at 30° of plantarflexion ( P = .393). Sectioning the CFL caused a significant increase in talar tilt compared with the ATFL cut state at 0° ( P < .001) and 30° of plantarflexion ( P < .001), but no increase in anterior drawer or Cotton tests. Conclusion: Complete native stability may not be attainable at time zero repair with the tested treatments. The option that best returned stability in anterior translation was augmented ATFL repair with nonaugmented CFL repair. The importance of the CFL as a primary ligamentous stabilizer for talar tilt was confirmed. Clinical Relevance: Evaluating lateral ankle stability and treatment with a 6 degrees of freedom robot should help delineate optimal treatment options. Findings in this study show that none of the repair methods at time zero restored kinematics to the intact state. Of the tested states, the augmented ATFL repair with CFL repair was the best option for controlling anterior translation at time zero. The importance of addressing the CFL to correct talar tilt instability was suggested as was the importance of a period of immobilization before beginning protected rehabilitation. The benefit of ATFL repair augmentation with suture tape is in limiting the postoperative motion in an anterior drawer motion to just 0.5 to 1 mm, but there was no significant improvement to talar tilt even with CFL repair, suggesting that further consideration should be given to CFL augmentation in future studies.

No Difference in Ligamentous Strain or Knee Kinematics Between Rectangular or Cylindrical Femoral Tunnels During Anatomic ACL Reconstruction With a Bone–Patellar Tendon–Bone Graft

Background: As our understanding of anterior cruciate ligament (ACL) anatomy has evolved, surgical techniques to better replicate the native anatomy have been developed. It has been proposed that the introduction of a rectangular socket ACL reconstruction to replace a ribbon-shaped ACL has the potential to improve knee kinematics after ACL reconstruction. Purpose: To compare a rectangular femoral tunnel (RFT) with a cylindrical femoral tunnel (CFT) in terms of replicating native ACL strain and knee kinematics in a time-zero biomechanical anatomic ACL reconstruction model using a bone–patellar tendon–bone (BTB) graft. Study Design: Controlled laboratory study. Methods: In total, 16 fresh-frozen, human cadaveric knees were tested in a 5 degrees of freedom, computed tomography–compatible joint motion simulator. Knees were tested with the ACL intact before randomization to RFT or CFT ACL reconstruction using a BTB graft. An anterior translation load and an internal rotation moment were each applied at 0°, 30°, 60°, and 90° of knee flexion. A simulated pivot shift was performed at 0° and 30° of knee flexion. Ligament strain and knee kinematics were assessed using computed tomography facilitated by insertion of zirconium dioxide beads placed within the substance of the native ACL and BTB grafts. Results: For the ACL-intact state, there were no differences between groups in terms of ACL strain or knee kinematics. After ACL reconstruction, there were no differences in ACL graft strain when comparing the RFT and CFT groups. At 60° of knee flexion with anterior translation load, there was significantly reduced strain in the reconstructed state ([mean ±standard deviation] CFT native, 2.82 ± 3.54 vs CFT reconstructed, 0.95 ± 2.69; RFT native, 2.77 ± 1.71 vs RFT reconstructed, 1.40 ± 1.76) independent of the femoral tunnel type. In terms of knee kinematics, there were no differences when comparing the RFT and CFT groups. Both reconstructive techniques were mostly effective in restoring native knee kinematics and ligament strain patterns as compared with the native ACL. Conclusion: In the time-zero biomechanical environment, similar graft strains and knee kinematics were achieved using RFT and CFT BTB ACL reconstructions. Both techniques appeared to be equally effective in restoring kinematics associated with the native ACL state. Clinical Relevance: These data suggest that in terms of knee kinematics and graft strain, there is no benefit in performing the more technically challenging RFT as compared with a CFT BTB ACL reconstruction.

Restoration of Joint Inclination in Total Knee Arthroplasty Offers Little Improvement in Joint Kinematics in Neutrally Aligned Extremities

Kinematically aligned total knee replacements have been shown to better restore physiological kinematics than mechanical alignment and also offer good postoperative satisfaction. The purpose of this study is to evaluate the extent to which an inclined joint line in a kinematically aligned knee can alter the postoperative kinematics. A multi-body dynamic simulation was used to identify kinematic changes in the joint. To accurately compare mechanical alignment, kinematic alignment and a natural knee, a “standard” patient with neutral alignment of the lower extremities was selected for modeling from a joint database. The arthroplasty models in this study were implanted with a single conventional cruciate-retaining prosthesis. Each model was subjected to a flexion movement and the anteroposterior translation of the femoral condyles was collected for kinematic analysis. The results showed that the mechanical alignment model underwent typical paradoxical anterior translation of the femoral condyles. Incorporating an inclined joint line in the model did not prevent the paradoxical anterior translation, but a 3° varus joint line in the kinematic alignment model could reduce the peak value of this motion by about 1 mm. Moreover, the inclined joint line did not restore the motion curve back to within the range of the kinematic curve of the natural knee. The results of this study suggest that an inclined joint line, as in the kinematic alignment model, can slightly suppress paradoxical anterior translation of the femoral condyles, but cannot restore kinematic motions similar to the physiological knee. This finding implies that prostheses intended to be used for kinematic alignment should be designed to optimize knee kinematics with the intention of restoring a physiological motion curve.

Anterior distal tibial plafond-plasty for the treatment of posttraumatic ankle osteoarthritis with anterior translation of the talus

Posttraumatic ankle osteoarthritis (OA) represents a significant challenge to orthopedic surgeons, especially in cases of anterior talar translation and concomitant impaction of the anterior distal tibial plafond. The aim of this study was to evaluate the clinical outcomes of an intra-articular osteotomy for the management of these patients. A total of 21 patients meeting our criteria were retrospectively reviewed. Sixteen patients sustained initial pilon fractures, while five patients had Weber type C ankle fractures. Anterior distal tibial plafond-plasty was performed to address the impaction and anterior translation of the talus. The American Orthopedic Foot and Ankle Society (AOFAS) hindfoot score and visual analog scale (VAS) score were utilized as clinical outcomes. The lateral talar station (LTS), tibial lateral surface (TLS) angle, tibial anterior surface angle and talocrural angle were evaluated pre- and postoperatively. The modified Kellgren-Lawrence score was used for the evaluation of sagittal ankle OA. The average age at surgery was 35 years, and the average follow-up duration was 34 months. The AOFAS hindfoot score increased from 26 to 71 (p < 0.01), and the VAS score improved from 7 to 2 (p < 0.01). The LTS improved from 9.0 to 2.3 mm (p < 0.01), and the TLS angle improved from 72° to 81° (p < 0.01). Of the 21 patients, 18 showed improvement in or no worsening of ankle OA on the sagittal plane, while 3 developed advanced ankle OA. A congruent ankle joint on the sagittal plane could be achieved by anterior distal tibial plafond-plasty. This is a valuable treatment option for the salvage of posttraumatic ankle OA with anterior translation of the talus.

Ultrasound Observation of Hip Translational Motion in Adolescent Dancers

Hip microinstability, characterized by supraphysiologic movement of the femoroacetabular joint, has recently been recognized as a clinically relevant pathology. The potentially detrimental effects of its presence on joint health make identifying microinstability important; however, due to its multifaceted nature, screening for microinstability presents challenges. Musculoskeletal ultrasound offers an opportunity to visualize the arthrokinematics of the femoroacetabular joint on dynamic evaluation. Dancers may be particularly afflicted by microinstability due to the unique demands of their discipline. This study describes a method for evaluating femoral translation using dynamic ultrasound in adolescent dancers. One hundred forty-two dancers (117 females and 25 males) were recruited from a northeast high school dance program. Females mean age was 16.02 ± 1.06 years, mean BMI 20.35 ± 2.30 kg/m2, and mean years of dance experience 10.91 ± 2.84 years. Males mean age was 15.84 ± 1.26 years, mean BMI 21.78 ± 2.84 kg/m2, and mean years of dance experience 7.96 ± 2.82 years. Two hundred eighty-four hips were visualized under ultrasound imaging with the participants in both a neutral position and with the hip extended and externally rotated. The distance (mm) the femoral head was positioned anterior to the acetabulum was recorded for both these positions. The calculated difference in these values represented anterior translation. For female hips, the total mean anterior translation was 1.23 ± 2.01mm (-4.8 to 9.30 mm); for male hips, the mean of anterior translation was 1.39 ± 2.22 mm (-7.90 to 5.90 mm). This study identified a normative value range for hip anterior translational motion under dynamic ultrasound among a healthy population of adolescent dancers.