Novel Device to Accurately Locate Femoral Insertion Landmark in Medial Patellofemoral Ligament (MPFL) Reconstruction

2017 ◽  
Author(s):  
Roopam Dey ◽  
Sarthak Patnaik ◽  
Sudesh Sivarasu
Keyword(s):  
Medial Patellofemoral Ligament ◽  
Double Bundle ◽  
Mpfl Reconstruction ◽  
Medial Aspect ◽  
Lateral Aspect ◽  
Novel Device ◽  
Patella Dislocations ◽  
The Common ◽  
Very High ◽  
High Chance

Medial Patello Femoral Ligament (MPFL) is the main stabilizer of the patellar bone in the knee complex. This fan shaped ligament prevents lateral dislocations of patella, especially during the initial 30° of knee flexion as there is minimal bony support from femur on the lateral aspect of the patella [1–2]. Patella dislocations are one of the common knee joint pathologies and it has been reported that each dislocation of the patella induces micro-tears in the MPFL [3]. It has been also observed in previous studies that there exists a very high chance of patellar re-dislocations for those individuals who have experienced the dislocation once. Complete MPFL rupture occurs in 94% of the patients suffering from repeated patellar dislocations [3–4]. Out of the 130 various methods of MPFL reconstruction, the Double Bundle Procedure is the most commonly used as it provides a larger degree of pain-free range of motion [5–8]. Locating the exact drilling location on the medial aspect of the patella and the medial femur is a challenge for the surgeon and literature suggests that the current procedure leads to non-anatomical placement of the ligament [9]. A novel device has been developed (Pat-Rig) to address the issue of locating the exact drill locations of the ligament graft tunnels into the patella [10–12]. This paper addresses the second problem of locating the femoral landmark accurately.

scholarly journals Reconstruction of the medial patellofemoral ligament using two blind transverse semi-patella tunnels and an implant-free technique for patellar fixation: a technical note

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Vasileios Raoulis ◽  
Aristeidis Zibis ◽  
Apostolos Fyllos ◽  
Michael-Alexander Malahias ◽  
Konstantinos Banios ◽  
...  
Keyword(s):  
Medial Patellofemoral Ligament ◽  
Articular Surface ◽  
Cruciate Ligament ◽  
Attachment Site ◽  
Double Bundle ◽  
Bone Tunnel ◽  
Mpfl Reconstruction ◽  
Femoral Bone ◽  
Double Bundle Technique ◽  
Bone Tunnels

Abstract Background The double-bundle technique with two points of patellar fixation in the upper half of the patella replicating the broad attachment site of the native medial patellofemoral ligament (MPFL) is the most commonly performed procedure for MPFL reconstruction. Complete transverse patella tunnels pose a threat to the integrity of the patella. We present an implant-free, double-bundle technique for MPFL reconstruction with gracilis autograft, overcoming the problem of complete patella bone tunnels and over-drilling. Methods After standard gracilis graft harvesting, the anteromedial side of the patella is exposed. With the guidance of an anterior-cruciate-ligament (ACL) tibia-aiming device, two 2-mm parallel guide pins are inserted from medial to lateral at the upper half of the patella. The two guide pins are over-drilled with a cannulated 4.5-mm drill bit 2-cm deep, to create two transverse blind semi-patellar tunnels. For the femoral fixation, a 2.4-mm guide pin with an eyelet is drilled at the Schöttle point and over-reamed with a 6-mm cannulated reamer to a depth of 30 mm. The two free ends of the graft (with two running Krakow sutures placed) are pulled into the two patella tunnels and the graft sutures are tied together with tension for stable graft fixation at the lateral patella rim. With the help of a femoral suture loop (which is inserted in the femoral bone tunnel), the graft-loop is advanced into the femoral bone tunnel and the graft is finally fixed with a 7-mm interference screw at 30° of knee flexion. Results The utilization of blind transverse tunnels (not trans-patellar tunnels) offers the advantage of avoiding stress risers at the patella. Thanks to the ACL tibia aiming device, multiple drilling, and breaching of the anterior patellar cortex or articular surface of the patella is avoided. Conclusions This implant-free, and consequently affordable technique, isolated or combined with bony procedures, minimizes possibilities for perioperative bony complications at the patella fixation site.

scholarly journals Anatomic Double-Bundle Medial Patellofemoral Ligament Reconstruction with Autologous Semitendinosus: Aperture Fixation Both at the Femur and the Patella

Joints ◽  
2017 ◽  
Vol 05 (04) ◽  
pp. 256-260 ◽  
Author(s):  
Michele Vasso ◽  
Katia Corona ◽  
Giuseppe Toro ◽  
Marco Rossini ◽  
Alfredo Schiavone Panni
Keyword(s):  
Patellar Dislocation ◽  
Ligament Reconstruction ◽  
Medial Patellofemoral Ligament ◽  
Double Bundle ◽  
Medial Epicondyle ◽  
Mpfl Reconstruction ◽  
Medial Patellofemoral Ligament Reconstruction ◽  
Adductor Tubercle ◽  
Aperture Fixation ◽  
Redislocation Rate

AbstractMedial patellofemoral ligament (MPFL) represents the main restraint against lateral patellar displacement. The MPFL insertion at the patella is up to 30 mm wide and is located along the upper half of the medial patellar rim. The femoral insertion of the MPFL is approximately 10 mm distal to the apex of the adductor tubercle and 16 mm proximal to the medial epicondyle. Since most of the patients suffer from MPFL rupture just after the first patellar dislocation, MPFL reconstruction results necessarily in all cases of chronic objective patellar instability to reestablish the primary passive patellofemoral stabilizer. Over time, different techniques of MPFL reconstruction have been proposed with promising results in terms of patient satisfaction and redislocation rate. However, each of these techniques may present peculiar problems and/or complications. An anatomic double-bundle MPFL reconstruction through an aperture fixation both at the femur and at the patella is here presented. The anatomic double-bundle MPFL reconstruction could allow recreating the fan-shape and biomechanics of original MPFL, whereas aperture fixation could provide a strong and safe fixation without risk of loosening or slackening of the graft.

Effect of Isolated Medial Patellofemoral Ligament Reconstruction in Patellofemoral Instability Regardless of Predisposing Factors

2020 ◽  
Author(s):  
Jae Ik Lee ◽  
Mohd Shahrul Azuan Jaffar ◽  
Han Gyeol Choi ◽  
Tae Woo Kim ◽  
Yong Seuk Lee
Keyword(s):  
Medial Patellofemoral Ligament ◽  
Trochlear Dysplasia ◽  
Case Series ◽  
Patellofemoral Instability ◽  
International Knee Documentation Committee ◽  
Predisposing Factors ◽  
Mpfl Reconstruction ◽  
Patellar Tilt ◽  
Case Series Study

AbstractThe purpose of this study was to evaluate the outcomes of isolated medial patellofemoral ligament (MPFL) reconstruction, regardless of the presence of predisposing factors. A total of 21 knees that underwent isolated MPFL reconstruction from March 2014 to August 2017 were included in this retrospective series. Radiographs of the series of the knee at flexion angles of 20, 40, and 60 degrees were acquired. The patellar position was evaluated using the patellar tilt angle, sulcus angle, congruence angle (CA), and Caton-Deschamps and Blackburne-Peel ratios. To evaluate the clinical outcome, the preoperative and postoperative International Knee Documentation Committee (IKDC) and Lysholm knee scoring scales were analyzed. To evaluate the postoperative outcomes based on the predisposing factors, the results were separately analyzed for each group. Regarding radiologic outcomes, 20-degree CA was significantly reduced from 10.37 ± 5.96° preoperatively to −0.94 ± 4.11° postoperatively (p = 0.001). In addition, regardless of the predisposing factors, delta values of pre- and postoperation of 20-degree CA were not significantly different in both groups. The IKDC score improved from 53.71 (range: 18–74) preoperatively to 94.71 (range: 86–100) at the last follow-up (p = 0.004), and the Lysholm score improved from 54.28 (range: 10–81) preoperatively to 94.14 (range: 86–100) at the last follow-up (p = 0.010). Isolated MPFL reconstruction provides a safe and effective treatment for patellofemoral instability, even in the presence of mild predisposing factors, such as trochlear dysplasia, increased patella height, increased TT–TG distance, or valgus alignment. This is a Level 4, case series study.

High origin of Profunda Femoris Artery - A Case Report

2017 ◽  
Vol 2 (05) ◽  
Author(s):  
Ashwinikumar Waghmare ◽  
Malashri .
Keyword(s):  
Femoral Artery ◽  
Lower Limb ◽  
Rectus Femoris ◽  
Inguinal Ligament ◽  
Vastus Medialis ◽  
Medial Aspect ◽  
Lateral Aspect ◽  
Profunda Femoris Artery ◽  
Male Cadaver ◽  
Profunda Femoris

Profunda Femoris Artery (PFA) arises from lateral aspect of femoral artery 3.5 cm distal to inguinal ligament. It gives lateral and medial circumflex femoral arteries from lateral and medial aspect respectively. Following variation was reported in right lower limb of a 60 year male cadaver, during routine dissection for medical students. Profunda Femoris Artery (PFA) arose from lateral aspect of femoral artery 1 cm distal to inguinal ligament, running laterally and down words parallel to femoral artery the profunda femoris passed beneath rectus femoris, sartorius and vastus medialis successively, finally pierced adductor magnus as forth perforator artery, 6 cm above knee joint.

scholarly journals Interference Screw Versus Suture Anchors for Femoral Fixation in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Study

2021 ◽  
Vol 9 (3) ◽  
pp. 232596712198928
Author(s):  
Heath P. Gould ◽  
Nicholas R. Delaney ◽  
Brent G. Parks ◽  
Roshan T. Melvani ◽  
Richard Y. Hinton
Keyword(s):  
Medial Patellofemoral Ligament ◽  
Interference Screw ◽  
Biomechanical Study ◽  
Graft Fixation ◽  
Mpfl Reconstruction ◽  
Suture Anchors ◽  
Femoral Fixation ◽  
Significant Difference ◽  
Load To Failure ◽  
The Mean

Background: Femoral-sided graft fixation in medial patellofemoral ligament (MPFL) reconstruction is commonly performed using an interference screw (IS). However, the IS method is associated with several clinical disadvantages that may be ameliorated by the use of suture anchors (SAs) for femoral fixation. Purpose: To compare the load to failure and stiffness of SAs versus an IS for the femoral fixation of a semitendinosus autograft in MPFL reconstruction. Study Design: Controlled laboratory study. Methods: Based on a priori power analysis, a total of 6 matched pairs of cadaveric knees were included. Specimens in each pair were randomly assigned to receive either SA or IS fixation. After an appropriate reconstruction procedure, the looped end of the MPFL graft was pulled laterally at a rate of 6 mm/s until construct failure. The best-fit slope of the load-displacement curve was then used to calculate the stiffness (N/mm) in a post hoc fashion. A paired t test was used to compare the mean load to failure and the mean stiffness between groups. Results: No significant difference in load to failure was observed between the IS and the SA fixation groups (294.0 ± 61.1 vs 250.0 ± 55.9; P = .352), although the mean stiffness was significantly higher in IS specimens (34.5 ± 9.6 vs 14.7 ± 1.2; P = .004). All IS reconstructions failed by graft pullout from the femoral tunnel, whereas 5 of the 6 SA reconstructions failed by anchor pullout. Conclusion: In this biomechanical study using a cadaveric model of MPFL reconstruction, SA femoral fixation was not significantly different from IS fixation in terms of load to failure. The mean load-to-failure values for both reconstruction techniques were greater than the literature-reported values for the native MPFL. Clinical Relevance: These results suggest that SAs are a biomechanically viable alternative for femoral-sided graft fixation in MPFL reconstruction.

scholarly journals Comparable outcome for autografts and allografts in primary medial patellofemoral ligament reconstruction for patellofemoral instability: systematic review and meta-analysis

2021 ◽  
Author(s):  
Filippo Migliorini ◽  
Andromahi Trivellas ◽  
Jörg Eschweiler ◽  
Matthias Knobe ◽  
Markus Tingart ◽  
...  
Keyword(s):  
Medial Patellofemoral Ligament ◽  
Meta Analysis ◽  
Patellofemoral Instability ◽  
Mpfl Reconstruction ◽  
Current Evidence ◽  
Level Of Evidence ◽  
Feasible Alternative ◽  
The Mean ◽  
Persistent Instability

Abstract Purpose This study updates the current evidence on the role of allografts versus autografts for medial patellofemoral ligament (MPFL) reconstruction in patients with patellofemoral instability. Methods The study was performed according to the PRISMA guidelines. In March 2021, a literature search in the main online databases was performed. Studies reporting quantitative data concerning primary MPFL reconstruction using an allograft were considered for inclusion. The Coleman Methodology Score was used to assess the methodological quality of the selected articles. Results Data from 12 studies (474 procedures) were retrieved. The mean follow-up was 42.2 (15–78.5) months. The mean age was 21.1 ± 6.2 years. 64.9% (285 of 439) of patients were female. At the last follow-up, the Tegner (p < 0.0001), Kujala (p = 0.002) and the Lysholm (p < 0.0001) scores were minimally greater in the autografts. The similarity was found in the rate of persistent instability sensation and revision. The allograft group evidenced a lower rate of re-dislocations (p = 0.003). Conclusion Allografts may represent a feasible alternative to traditional autograft for MPFL reconstruction in selected patients with patellofemoral instability. Allograft tendons yielded similar PROMs, rates of persistent instability, and revision. Allograft reconstructions tended to have modestly lower re-dislocation rates. Level of evidence IV.

scholarly journals Common issues in the hetero-epitaxial seeding on SiC substrates in the sublimation growth of AlN crystals

2021 ◽  
Vol 127 (8) ◽  
Author(s):  
R. Radhakrishnan Sumathi
Keyword(s):  
Power Electronic ◽  
Etch Pit ◽  
Micro Hole ◽  
Wet Chemical ◽  
The Common ◽  
Common Problems ◽  
Hole Defects ◽  
Sublimation Growth ◽  
Impurity Elements ◽  
Very High

AbstractAluminium nitride (AlN) is a futuristic material for efficient next-generation high-power electronic and optoelectronic applications. Sublimation growth of AlN single crystals with hetero-epitaxial approach using silicon carbide substrates is one of the two prominent approaches emerged, since the pioneering crystal growth work from 1970s. Many groups working on this hetero-epitaxial seeding have abandoned AlN growth altogether due to lot of persistently encountered problems. In this article, we focus on most of the common problems encountered in this process such as macro- and micro-hole defects, cracks, 3D-nucleation, high dislocation density, and incorporation of unintentional impurity elements due to chemical decomposition of the substrate at very high temperatures. Possible ways to successfully solve some of these issues have been discussed. Other few remaining challenges, namely low-angle grain boundaries and deep UV optical absorption, are also presented in the later part of this work. Particular attention has been devoted in this work on the coloration of the crystals with respect to chemical composition. Wet chemical etching gives etch pit density (EPD) values in the order of 105 cm-2 for yellow-coloured samples, while greenish coloration deteriorates the structural properties with EPD values of at least one order more.

Molecule-Based Magnets—An Overview

MRS Bulletin ◽  
2000 ◽  
Vol 25 (11) ◽  
pp. 21-30 ◽  
Author(s):  
Joel S. Miller ◽  
Arthur J. Epstein
Keyword(s):  
Low Temperature ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Magnetic Ordering ◽  
Low Density ◽  
Materials Properties ◽  
The Common ◽  
New Processing ◽  
Very High

Molecule-based magnets are a broad, emerging class of magnetic materials that expand the materials properties typically associated with magnets to include low density, transparency, electrical insulation, and low-temperature fabrication, as well as combine magnetic ordering with other properties such as photoresponsiveness. Essentially all of the common magnetic phenomena associated with conventional transition-metal and rare-earth-based magnets can be found in molecule-based magnets. Although discovered less than two decades ago, magnets with ordering temperatures exceeding room temperature, very high (∼27.0 kOe or 2.16 MA/m) and very low (several Oe or less) coercivities, and substantial remanent and saturation magnetizations have been achieved. In addition, exotic phenomena including photoresponsiveness have been reported. The advent of molecule-based magnets offers new processing opportunities. For example, thin-film magnets can be prepared by means of low-temperature chemical vapor deposition and electrodeposition methods.

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