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The anterolateral ligament (ALL) has been suggested as an important secondary knee restrain on the dynamic laxity in anterior cruciate ligament- (ACL-) deficient knees. Nevertheless, its kinematical contribution to the pivot-shift (PS) phenomenon has not been clearly and objectively defined, and noninvasive sensor technology could give a crucial contribution in this direction. The aim of the present study was to quantify in vitro the PS phenomenon in order to investigate the differences between an ACL-deficient knee and an ACL+ALL-deficient knee. Ten fresh-frozen paired human cadaveric knees ( n = 20 ) were included in this controlled laboratory study. Intact, ACL-deficient, and ACL+ALL-deficient knees were subjected to a manual PS test quantified by a noninvasive triaxial accelerometer (KiRA, OrthoKey). Kinematic data (i.e., posterior acceleration of the tibial lateral compartment) were recorded and compared among the three statuses. Pairwise Student’s t -test was used to compare the single groups ( p < 0.05 ). Intact knees, ACL-deficient knees, and ACL+ALL-deficient knees showed an acceleration of 5.3 ± 2.1 m/s2, 6.3 ± 2.3 m/s2, and 7.8 ± 2.1 m/s2, respectively. Combined sectioning of ACL and ALL resulted in a statistically significant acceleration increase compared to both the intact state ( p < 0.01 ) and the ACL-deficient state ( p < 0.01 ). The acceleration increase determined by isolated ACL resection compared to the intact state was not statistically significant ( p > 0.05 ). The ALL sectioning increased the rotatory laxity during the PS after ACL sectioning as measured through a user-friendly, noninvasive triaxial accelerometer.

Purpose: To evaluate if there was a correlation between in vivo kinematics of a medial-stabilized (MS) total knee arthroplasty (TKA) and post-operative clinical scores. We hypothesized that (1) a MS-TKA would produce a medial pivot movement and that (2) this specific pattern would be correlated with higher clinical scores. Methods: 18 patients were evaluated through clinical and functional scores evaluation (Knee Society Score clinical and functional, Womac, Oxford), and kinematically through dynamic radiostereometric analysis (RSA) at 9months after MS-TKA, during the execution of a sit-to-stand and a lunge motor task. The anteroposterior (AP) Low Point translation of medial and lateral femoral compartments was compared through Student’s t test (p < 0.05). A correlation analysis between scores and kinematics was performed through the Pearson’s correlation coefficient r. Results: A significantly greater (p < 0.0001) anterior translation of the lateral compartment with respect to the medial one was found in both sit-to-stand (medial 2.9mm ± 0.7mm, lateral 7.1mm ± 0.6mm) and lunge (medial 5.3mm ± 0.9mm, lateral 10.9mm ± 0.7mm) motor tasks, thus resulting in a medial pivot pattern in about 70% of patients. Significant positive correlation in sit-to-stand was found between the peak of AP translation in the lateral compartment and clinical scores (r = 0.59 for Knee Society Score clinical and r = 0.61 for Oxford). Moreover, we found that the higher peak of AP translation of the medial compartment correlated with lower clinical scores (r = − 0.55 for Knee Society Score clinical, r = − 0.61 for Womac and r = − 0.53 for Oxford) in the lunge. A negative correlation was found between Knee Society Score clinical and VV laxity during sit-to-stand (r = − 0.56) and peak of external rotation in the lunge motor task (r = − 0.66). Conclusions: The MS-TKA investigated produced in vivo a medial pivot movement in about 70% of patients in both examined motor tasks. There was a correlation between the presence of medial pivot and higher post-operative scores. Level of evidence: IV.

How to restore native knee kinematics following complex knee injuries is still debated and under investigation. To better reproduce the native anterior cruciate ligament (ACL), surgeons have a host of different options, including graft choice, technique, fixation method, and single-, double-, and triple-bundle techniques, etc. Isolated ACL reconstruction alone is not effective in controlling complex instability patterns, especially regarding internal and external rotations. Several techniques have been described to address such instabilities, like single- or double- bundle ACL reconstruction plus lateral extra-articular tenodesis. In truth, chronic ACL injury requires reconstruction plus lateral tenodesis to control rotational instability. Additional technical complexity may result in complications without improved outcomes. Neither single-bundle nor double-bundle techniques are “truly” anatomic. Keep it simple; keep it safe.

Introduction Injuries involving the tarsometatarsal (TMT) joint are relatively uncommon, and the surgical treatment is potentially characterized by a high complications rate. The purpose of this study is to evaluate the results of the treatment of Lisfranc fracture-dislocations treated with closed reduction and percutaneous fixation with K-wires, considering complications and re-intervantion rate. Materials and methods A retrospective review was performed on all patients undergone closed reduction and percutaneous fixation with K-wires of a Lisfranc fracture-dislocation. Patients have been clinically evaluated at last follow up by American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score and Visual Analogue Scale (VAS), as well as by radiograph assessment. Results Following inclusion and exclusion criteria, 15 patients have been included, with a mean age of 48.2 ± 5.6 years. Average follow-up was 3.8 ± 1.8 years (range 1–6). 7 fractures analyzed were classified as type A, 7 as type B (3 were B1, 4 were B2) and 1 as type C1. No case of loss of reduction has been observed at radiographic 1-month follow-up. At last follow-up mean AOFAS midfoot score and VAS score were respectively 82.2 ± 10.4 and 1.5 ± 1.3. Registered complications showed one deep vein thrombosis and 2 cases of complex regional pain syndrome (CRPS). One patient subsequently underwent arthrodesis of the tarsometatarsal joint for post-traumatic arthritis. Conclusions The treatment of the fracture-dislocations of the Lisfranc joint by percutaneous reduction and fixation with K-wire can achieve good clinical outcomes with a low rate of complications and reoperations. Level of Evidence Level IV

Purpose This work presents a kinematic evaluation of a cruciate retaining highly congruent mobile bearing total knee arthroplasty design using dynamic Roentgen sterephotogrammetric analysis. The aim was to understand the effect of this implant design on the kinematics of prosthetic knees during dynamic activities. Methods A cohort of 15 patients was evaluated at nine month follow-up after surgery. The mean age was 74.8 (range 66–85) years. The kinematics was evaluated using the Grood and Suntay decomposition and the Low-Point (LP) methods. Results ?tlsb=-0.15pt?>From sitting to standing up position, the femoral component internally rotated (from − 11.3 ± 0.2° to − 7.0 ± 0.2°). Varus–valgus rotations were very close to 0° during the whole motor task. LP of medial condyle moved from an anterior position of 12.0 ± 0.2 mm to a posterior position of − 12.4 ± 0.2 mm; LP of the lateral condyle moved from an anterior position of 8.1 ± 0.2 mm to a posterior position of − 12.4 ± 0.2 mm, showing a bi-condylar rollback where both condyles moved parallel backward. Moreover, the femoral component showed anterior translation with respect to the tibia from 80° to 20° (from − 4.9 ± 0.2 mm to 3.3 ± 0.2 mm), then a posterior translation from 20° to full extension was identified (from 3.3 ± 0.2 mm to 0.5 ± 0.2 mm). Conclusions Paradoxical anterior femoral translation and absence of medial-pivoting motion were recorded, highlighting the role of the symmetric deep dishes insert as main driver of the kinematic of this TKA design.

Which total knee arthroplasty (TKA) design represents the better solution to restore a correct knee biomechanics is still debated. The aim of this study was to compare posterior stabilized (PS) and cruciate retaining (CR) version of the same TKA design (femoral component with an anatomic sagittal radius—J-curve design) by the use of dynamic Roentgen stereophotogrammetric analysis (RSA). The hypothesis was that the two models influence differently in vivo knee kinematic. A cohort of 16 randomly selected patients was evaluated 9 months after surgery: Zimmer PERSONA® was implanted, eight with CR design and eight with PS design. The kinematic evaluations were performed using a Dynamic RSA (BI-STAND DRX 2) developed in our Institute, during the execution of the sit-to-stand motor task. The motion parameters were obtained using the Grood and Suntay decomposition and the low-point kinematics methods. PS TKA lateral femoral compartment had a wider anterior translation (17 ± 2 mm) than the medial one (11 ± 2 mm), while the two compartments of CR TKA showed a similar anterior translation (medial: 9 ± 2 mm/lateral: 11 ± 2 mm). T test for comparison between CR and PS TKA of antero-posterior translation showed a statistically significant difference (p

Background: Return to sport after revision ACL reconstruction is a controversial topic, several studies reported the results of different techniques and graft in sportsman, presenting an incredibly wide range of return to the same pre-injury activity level, from 0% to 100%. The purpose of this study was to evaluate the clinical outcomes and return to sport rate in young athletes after non anatomic double-bundle revision ACL reconstruction with Achilles allograft. Hypothesis: The present revision technique was effective in terms of stability, return to sport and functional outcomes. Material and methods: All the athletes undergone Revision ACL reconstruction with non-irradiated Achilles tendon allograft with a non-anatomical double-bundle technique were included in the study. A split Achilles tendon allograft was used to reproduce the anteromedial (AM) bundle using the over-the-top position, while the posterolateral (PL) bundle was reconstructed through a femoral tunnel located in the anatomical PL footprint. Sport activity, knee function with Lysholm score, knee laxity and re-injury or re-operations were evaluated. Results: Twenty-six athletes (23 males, three females) with a mean age of 23.4. ±. 3.6 years were evaluated at a mean follow-up of 6.0. ±. 1.6 years. Overall 69% of patients returned to sport both at elite (44%) or county level (56%) after a mean 6.7. ±. 1.5 (3-9 range) months. The mean Lysholm score showed a significant improvement from 64.4. ±. 8.1 at pre-operative status to 83.8. ±. 11.3 at final follow-up (P 5. mm side-to-side difference at KT-1000. Therefore, the overall survival rate at mean six years follow-up was 81%. Conclusion: The ACL revision with a double-bundle technique using Achilles tendon allograft was successful in 81% of athletes at six years mean follow-up. Type of study and level of evidence: Retrospective case series, level IV.

Background: Significantly better stability may be achieved with a Single Bundle Lateral Plasty (SBLP) reconstruction compared with the Single Bundle (SB) and Double Bundle (DB) procedures. Methods: The study included 42 patients who underwent ACL reconstruction. Patients were randomly selected for one of the following surgical procedure defining three study groups: Single-Bundle-Lateral-Plasty, Single-Bundle and Double-Bundle procedures. Laxity evaluation was performed with an intraoperative navigation system. Lachman test (AP30), Drawer test (AP90), Varus-Valgus stress test at 0° and 30° knee flexion (VV0, VV30), Internal-External rotation (IE30, IE90), and pivot shift (PS) test are the clinical test executed for the laxity evaluation. Laxity reduction was defined as the difference between laxity before the fixation of the graft used for the reconstruction and the laxity just after its fixation. Findings: For all the analyzed surgical techniques, the pre-reconstruction laxity values were statistically higher (P < 0.05) than the post-reconstruction values for all the analyzed tests. The analysis of the Drawer test and Internal-External rotation at 30° and 90° of knee flexion, highlighted a significant difference at time zero after surgery among the three study groups. The results showed that the SBLP technique had the highest reduction values compared to SB (PIE90 = 0.001) and DB (PAP90 = 0.012; PIE30 = 0.021; PIE90 = 0.003) techniques. Interpretation: SBLP technique showed significantly superior results in terms of antero-posterior and internal-external laxity reduction at time-zero after ACL reconstruction.

The hypothesis was that an alteration of different surgical variables of ACL reconstruction would produce significant changes in post-operative static laxity of knee joint. Joint laxity was acquired by a surgical navigation system for 17 patients just after graft fixation during single-bundle reconstruction with extra-articular lateral tenodesis. The analysed laxity parameters were: internal/external rotation at 30° (IE30) and 90° (IE90) of flexion, varus/valgus rotation at 0° (VV0) and 30° (VV30) of flexion and anterior/posterior displacement at 30° (AP30) and 90° (AP90) of flexion. As surgical variables, the angles between the tibial tunnel and the three planes were defined as well as the lengths of the tunnel and the relationship between native footprints and tunnels. The same analysis was performed for the femoral side. All surgical variables were combined in a multivariate analysis to assess for predictive factors between them and post-operative laxities values. To quantify the performance of each multivariate model, the correlation ratio (η 2) and the corresponding P value (*P

In this chapter we analyze our experience concerning ACL lesion with an associated peripheral instability, as peripheral structures are getting more and more attention. We know that combined damage of the ACL and the posterolateral structures of the knee have been associated to Chronic anterior cruciate ligament laxity, in particular rotational laxity associated with a severe pivot-shift test (PST). Posterolateral structures, that may not have been yet directly identified, probably act as secondary restraints to the PST, supplementing the primary restraint role of the ACL in anteroposterior laxity, with emphasis on rotatory laxity and internal rotation. The persistence of this rotatory laxity has been reported even after cases of uneventful ACL reconstruction, suggesting that a single-bundle intra-articular reconstruction could not be sufficient to completely restore rotational knee stability in certain patients (Tashman et al, Am J Sports Med 32(4):975–983, 2004). The rationale behind extra-articular plasty is therefore to create a restraint in internal tibial rotation, and that’s why we adopted in our Institute since 1993 Marcacci’s technique with good results and good graft survivorship. Authors who favour the supplementary extra-articular plasty to standard ACL reconstruction, report the reduction of the PST and lateral tibial translation, however the introduction of evidence-based inclusion criteria for any similar technique as a primary or a revision option,is difficult and remains sporadical and empirically-based.