MRI follow-up of conservatively treated meniscal knee lesions in general practice

Objective: To evaluate meniscal status change on follow-up MRI after 1 year, prognostic factors and association with clinical outcome in patients with conservatively treated knee injury. Methods: We analysed 403 meniscal horns in 101 conservatively treated patients (59 male; mean age 40 years) in general practice who underwent initial knee MRI within 5 weeks of trauma. We performed ordinal logistic regression analysis to analyse prognostic factors for meniscal change on follow-up MRI after 1 year, and we assessed the association with clinical outcome. Results: On follow-up MRI 49 meniscal horns had deteriorated and 18 had improved. Age (odds ratio [OR] 1.3/decade), body weight (OR 1.2/10 kg), total anterior cruciate ligament (ACL) rupture on initial MRI (OR 2.4), location in the posterior horn of the medial meniscus (OR 3.0) and an initial meniscal lesion (OR 0.3) were statistically significant predictors of meniscal MRI appearance change after 1 year, which was not associated with clinical outcome. Conclusion: In conservatively treated patients, meniscal deterioration on follow-up MRI 1 year after trauma is predicted by higher age and body weight, initial total ACL rupture, and location in the medial posterior horn. Change in MRI appearance is not associated with clinical outcome

Restoring tibiofemoral alignment during ACL reconstruction results in better knee biomechanics

"Published online: 24 October 2017"PURPOSE: Anterior cruciate ligament (ACL) reconstruction (ACLR) aims to restore normal knee joint function, stability and biomechanics and in the long term avoid joint degeneration. The purpose of this study is to present the anatomic single bundle (SB) ACLR that emphasizes intraoperative correction of tibiofemoral subluxation that occurs after ACL injury. It was hypothesized that this technique leads to optimal outcomes and better restoration of pathological tibiofemoral joint movement that results from ACL deficiency (ACLD). METHODS: Thirteen men with unilateral ACLD were prospectively evaluated before and at a mean follow-up of 14.9 (SD = 1.8) months after anatomic SB ACLR with bone patellar tendon bone autograft. The anatomic ACLR replicated the native ACL attachment site anatomy and graft orientation. Emphasis was placed on intraoperative correction of tibiofemoral subluxation by reducing anterior tibial translation (ATT) and internal tibial rotation. Function was measured with IKDC, Lysholm and the Tegner activity scale, ATT was measured with the KT-1000 arthrometer and tibial rotation (TR) kinematics were measured with 3Dmotion analysis during a high-demand pivoting task. RESULTS: The results showed significantly higher TR of the ACL-deficient knee when compared to the intact knee prior to surgery (12.2° ± 3.7° and 10.7° ± 2.6° respectively, P = 0.014). Postoperatively, the ACLR knee showed significantly lower TR as compared to the ACL-deficient knee (9.6°±3.1°, P = 0.001) but no difference as compared to the control knee (n.s.). All functional scores were significantly improved and ATT was restored within normal values (P < 0.001). CONCLUSIONS: Intraoperative correction of tibiofemoral subluxation that results after ACL injury is an important step during anatomic SB ACLR. The intraoperative correction of tibiofemoral subluxation along with the replication of native ACL anatomy results in restoration of rotational kinematics of ACLD patients to normal levels that are comparable to the control knee. These results indicate that the reestablishment of tibiofemoral alignment during ACLR may be an important step that facilitates normal knee kinematics postoperatively. LEVEL OF EVIDENCE: Level II, prospective cohort study.The authors gratefully acknowledge the funding support from the Hellenic Association of Orthopaedic Surgery and Traumatology (HAOST-EEXOT)info:eu-repo/semantics/publishedVersio

Effects of low intensity pulsed ultrasound with and without increased cortical porosity on structural bone allograft incorporation

<p>Abstract</p> <p>Background</p> <p>Though used for over a century, structural bone allografts suffer from a high rate of mechanical failure due to limited graft revitalization even after extended periods <it>in vivo</it>. Novel strategies that aim to improve graft incorporation are lacking but necessary to improve the long-term clinical outcome of patients receiving bone allografts. The current study evaluated the effect of low-intensity pulsed ultrasound (LIPUS), a potent exogenous biophysical stimulus used clinically to accelerate the course of fresh fracture healing, and longitudinal allograft perforations (LAP) as non-invasive therapies to improve revitalization of intercalary allografts in a sheep model.</p> <p>Methods</p> <p>Fifteen skeletally-mature ewes were assigned to five experimental groups based on allograft type and treatment: +CTL, -CTL, LIPUS, LAP, LIPUS+LAP. The +CTL animals (n = 3) received a tibial ostectomy with immediate replacement of the resected autologous graft. The -CTL group (n = 3) received fresh frozen ovine tibial allografts. The +CTL and -CTL groups did not receive LAP or LIPUS treatments. The LIPUS treatment group (n = 3), following grafting with fresh frozen ovine tibial allografts, received ultrasound stimulation for 20 minutes/day, 5 days/week, for the duration of the healing period. The LAP treatment group (n = 3) received fresh frozen ovine allografts with 500 μm longitudinal perforations that extended 10 mm into the graft. The LIPUS+LAP treatment group (n = 3) received both LIPUS and LAP interventions. All animals were humanely euthanized four months following graft transplantation for biomechanical and histological analysis.</p> <p>Results</p> <p>After four months of healing, daily LIPUS stimulation of the host-allograft junctions, alone or in combination with LAP, resulted in 30% increases in reconstruction stiffness, paralleled by significant increases (p < 0.001) in callus maturity and periosteal bridging across the host/allograft interfaces. Longitudinal perforations extending 10 mm into the proximal and distal endplates filled to varying degrees with new appositional bone and significantly accelerated revitalization of the allografts compared to controls.</p> <p>Conclusion</p> <p>The current study has demonstrated in a large animal model the potential of both LIPUS and LAP therapy to improve the degree of allograft incorporation. LAP may provide an option for increasing porosity, and thus potential <it>in vivo </it>osseous apposition and revitalization, without adversely affecting the structural integrity of the graft.</p

Changes of meniscal interhorn distances: An in vivo magnetic resonance imaging study

The aim of this study was to evaluate the changes of the internal (IID) and external meniscal interhorn distance (EID) of the medial and the lateral meniscus under loading. Sagittal magnetic resonance images of 15 knees were studied. The medial and lateral meniscus were examined with the knee at 0 degrees and 30 degrees of flexion, under no load, with load equal to 50% of body weight and with load equal to 100% of body weight. Under no load, the mean IID was 19.9 mm for the medial meniscus and 12.3 mm for the lateral meniscus and the mean EID was 44.6 mm for the medial meniscus and 34.4 mm for the lateral meniscus. Under load equal to 50% and 100% of patient’s body weight, there was a significant increase in both distances (p &lt; 0.05). Under constant loading, flexion of the knee from 0 degrees to 30 degrees, decreased the EID of both menisci. In conclusion, loading increases both IID and EID. Knee position affects only the EID. The quality of magnetic resonance images may affect the reliability of such measurements. (c) 2005 Elsevier B.V. All rights reserved

Differences in graft orientation using the transtibial and anteromedial portal technique in anterior cruciate ligament reconstruction: a magnetic resonance imaging study

The purpose of this study was to evaluate differences in graft orientation between transtibial (TT) and anteromedial (AM) portal technique using magnetic resonance imaging (MRI) in anterior cruciate ligament (ACL) reconstruction. Fifty-six patients who were undergoing ACL reconstruction underwent MRI of their healthy and reconstructed knee. Thirty patients had ACL reconstruction using the TT (group A), while in the remaining 26 the AM (group B) was used. In the femoral part graft orientation was evaluated in the coronal plane using the femoral graft angle (FGA). The FGA was defined as the angle between the axis of the femoral tunnel and the joint line. In the tibial part graft orientation was evaluated in the sagittal plane using the tibial graft angle (TGA). The TGA was defined as the angle between the axis of the tibial tunnel and a line perpendicular to the long axis of the tibia. The ACL angle of the normal knee in the sagittal view was also calculated. The mean FGA for group A was 72A degrees, while for the group B was 53A degrees and this was statistically significant (P < 0.001). The mean TGA for group A was 64A degrees, while for the group B was 63A degrees (P = 0.256). The mean intact ACL angle for group A was 52A degrees, while for the group B was 51A degrees. The difference between TGA and intact ACL angle was statistically significant (P < 0.001) for both groups. Using the AM portal technique, the ACL graft is placed in a more oblique direction in comparison with the TT technique in the femoral part. However, there are no differences between the two techniques in graft orientation in the tibial part. Normal sagittal obliquity is not restored with both techniques