Rotator cuff tears are common and result in considerable morbidity. Tears within the tendon substance or at its insertion into the humeral head represent a considerable clinical challenge because of the hostile local environment that precludes healing. Tears often progress without intervention, and current surgical treatments are inadequate.
View Article and Find Full Text PDFBackground: In recent years there has been an increasing interest in high tibial osteotomy (HTO) to treat patients with chronic knee instability due to posterolateral corner (PLC), posterior cruciate ligament (PCL), and anterior cruciate ligament (ACL) insufficiencies with concurrent malalignment in the coronal and/or sagittal plane.
Purpose: To perform a systematic review of the use of HTO for the treatment of knee ligament instability with concurrent malalignment.
Study Design: Systematic review; Level of evidence, 4.
Knee Surg Sports Traumatol Arthrosc
August 2017
Purpose: The purpose of this study was to determine the biomechanical effects of simulated immediate motion and weightbearing during rehabilitation on different double-bundle posterior cruciate ligament reconstruction (DB-PCLR) graft options.
Methods: Nine each of commercially prepared (allograft) Achilles tendon allografts, fresh-frozen (autograft) bone-patellar tendon-bone grafts, and fresh-frozen quadriceps tendon grafts were paired with commercially prepared anterior tibialis allografts, fresh-frozen semitendinosus grafts, and fresh-frozen semitendinosus grafts, respectively. Graft pairs were loaded to simulate early range of motion on a stationary bicycle, partial weightbearing (30 %), and full weightbearing.
Background: The purpose of this study was to quantify the meniscal root anatomy of the New Zealand white rabbit to better understand this animal model for future in vitro and in vivo joint degeneration studies.
Methods: Ten non-paired fresh frozen New Zealand white rabbit knee stifle joints were carefully disarticulated for this study. Measurements were made for all bony landmarks and ligamentous structure attachment sites on the tibial plateau.
Background: Recent biomechanical studies have demonstrated that an extra-articular lateral knee structure, most recently referred to as the anterolateral ligament (ALL), contributes to overall rotational stability of the knee. However, the effect of anatomic ALL reconstruction (ALLR) in the setting of anterior cruciate ligament (ACL) reconstruction (ACLR) has not been biomechanically investigated or validated.
Purpose/hypothesis: The purpose of this study was to investigate the biomechanical function of anatomic ALLR in the setting of a combined ACL and ALL injury.
Background: Bone marrow aspirate concentrate (BMAC) has emerged as a novel treatment for pathology of the knee. Despite containing a limited number of stem cells, BMAC serves as a source of growth factors that are thought to play an important role as a result of their anabolic and anti-inflammatory effects. To our knowledge, there is no systematic review regarding the outcomes of bone marrow aspirate concentrate used for the treatment of chondral defects and osteoarthritis of the knee.
View Article and Find Full Text PDFJ Orthop Sports Phys Ther
February 2016
There is a growing body of evidence surrounding the pathology and treatment of meniscal root tears. As surgical techniques are being developed and refined, rehabilitation protocols for meniscal root repairs must be defined and tested. Little information has been published regarding specific rehabilitation parameters for meniscal root repairs through all phases of rehabilitation.
View Article and Find Full Text PDFBackground: Recent investigations have described the structural and functional behavior of the anterolateral ligament (ALL) of the knee through pull-apart and isolated sectioning studies. However, the secondary stabilizing role of the ALL in the setting of a complete anterior cruciate ligament (ACL) tear has not been fully defined for common simulated clinical examinations, such as the pivot-shift, anterior drawer, and internal rotation tests.
Hypothesis: Combined sectioning of the ALL and ACL would lead to increased internal rotation and increased axial plane translation during a pivot-shift test when compared with isolated sectioning of the ACL.
Background: Complete radial tears of the medial meniscus have been reported to be functionally similar to a total meniscectomy. At present, there is no consensus on an ideal technique for repair of radial midbody tears of the medial meniscus. Prior attempts at repair with double horizontal mattress suture techniques have led to a reportedly high rate of incomplete healing or healing in a nonanatomic (gapped) position, which compromises the ability of the meniscus to withstand hoop stresses.
View Article and Find Full Text PDFBackground: Anatomic landmarks located on the proximal femur have only recently been defined, and there is a lack of radiographic guidelines for their locations presented in the literature. With the confident identification of these landmarks, radiographs could provide more assistance in preoperative evaluations, intraoperative guidance, and postoperative assessments.
Purpose: To quantify the radiographic locations of endoscopic landmarks of the proximal femur.
Background: The anatomy of the acetabulum has been described extensively in the literature, but radiographic acetabular guidelines have not been well established. This study provides a radiographic map of acetabular landmarks in the hip.
Purpose/hypothesis: The purpose of this study was to quantify the precise radiographic location of arthroscopic landmarks around the acetabulum.
Meniscal tears differ in terms of pattern and location. If left untreated, a meniscal tear can lead to the development of osteoarthritis and increased pain, swelling, and functional limitations. Tears in the vascularized outer two-thirds of the meniscus can often be successfully repaired with use of an inside-out technique.
View Article and Find Full Text PDFCurrently, there exists a need for a more thorough understanding of native hip joint kinematics to improve the understanding of pathological conditions, injury mechanisms, and surgical interventions. A biomechanical testing system able to accomplish multiple degree-of-freedom (DOF) movements is required to study the complex articulation of the hip joint. Therefore, the purpose of this study was to assess the repeatability and comparative accuracy of a 6 DOF robotic system as a testing platform for range of motion in vitro hip biomechanical analysis.
View Article and Find Full Text PDFBackground: Biomechanical studies have reported that the posterior cruciate ligament (PCL) functions as a restraint against excessive tibial internal rotation at higher degrees of knee flexion.
Purpose: To investigate the use of a supine internal rotation (IR) test for the diagnosis of grade III PCL injuries. The hypothesis was that internal rotation would be greater in patients with grade III PCL injuries compared with other knee injuries and that the supine IR test would demonstrate excellent diagnostic accuracy.
Background: A majority of studies investigating the role of the ligamentum teres (LT) have focused primarily on anatomical and histological descriptions. To date, however, the structural properties of the LT have yet to be fully elucidated.
Purpose: To investigate the structural properties of the native LT in a human cadaveric model.
Meniscal root tears are substantial injuries that usually require surgical management. If left untreated, meniscal root tears can lead to the rapid onset of osteoarthritis similar to that seen after a total meniscectomy. Meniscal root tears often go unnoticed on magnetic resonance imaging and arthroscopy, in large part because meniscal root anatomy and its biomechanical importance have been defined only recently.
View Article and Find Full Text PDFBackground: An injury to the deltoid ligament complex of the ankle can require surgical intervention in cases of chronic instability. There is an absence of data describing medial ankle ligament anatomy on standard radiographic views.
Purpose: To quantitatively describe the anatomic origins and insertions of the individual ligamentous bands of the superficial and deep deltoid on standard lateral and mortise radiographic views with reference to osseous landmarks and anatomic axes.
Although injuries to the posterolateral corner of the knee were previously considered to be a rare condition, they have been shown to be present in almost 16% of all knee injuries and are responsible for sustained instability and failure of concomitant reconstructions if not properly recognized. Although also once considered to be the "dark side of the knee", increased knowledge of the posterolateral corner anatomy and biomechanics has led to improved diagnostic ability with better understanding of physical and imaging examinations. The management of posterolateral corner injuries has also evolved and good outcomes have been reported after operative treatment following anatomical reconstruction principles.
View Article and Find Full Text PDFKnee Surg Sports Traumatol Arthrosc
April 2016
Purpose: The purpose of this study was to quantitatively describe the locations of the syndesmotic ligaments and the tibiofibular articulating cartilage surfaces on standard radiographic views using reproducible radiographic landmarks and reference axes.
Methods: Twelve non-paired ankles were dissected to identify the anterior-inferior tibiofibular ligament (AITFL), posterior-inferior tibiofibular ligament (PITFL), interosseous tibiofibular ligament (ITFL), and the cartilage surfaces of the syndesmosis. Structures were marked with 2-mm radiopaque spheres prior to obtaining lateral and mortise radiographs.
Background: There is a paucity of outcome data to guide the surgical treatment of acute grade III posterolateral corner (PLC) knee injuries.
Purpose: To systematically review the literature to compare clinical outcomes of the treatment for acute grade III PLC injuries.
Study Design: Systematic review; Level of evidence, 4.
Background: There are a variety of reported surgical techniques outcomes of chronic grade III posterolateral corner (PLC) knee injuries. It is unknown if outcomes differ among the various surgical treatments.
Purpose: To systematically review the literature and report subjective and objective outcomes for surgical treatment strategies for chronic grade III PLC injuries to determine the optimal surgical technique.
Purpose: The purpose of this study was to investigate the effect of lateral meniscal posterior root avulsions combined with intact meniscofemoral ligaments (MFLs), deficient MFLs, anterior cruciate ligament (ACL) tears and reconstructions, and root repairs using an established tibiofemoral contact mechanics testing protocol.
Methods: Ten fresh-frozen cadaveric knees were tested with six knee conditions (1: intact; 2: lateral meniscal posterior root avulsion; 3: root avulsion and deficient MFLs; 4: condition 3 with ACL tear; 5: condition 4 with ACL reconstruction; 6: ACL reconstruction with root repair) at five flexion angles (0°, 30°, 45°, 60°, and 90°), under a 1000-N axial load. Contact area and pressure were measured with Tekscan sensors.
Background: While the nonoperative management of Achilles tendon ruptures is a viable option, surgical repair is preferred in healthy and active populations. Recently, minimally invasive percutaneous repair methods with assistive devices have been developed.
Hypothesis/purpose: The purpose of this study was to biomechanically analyze 3 commercially available, minimally invasive percutaneous techniques compared with an open Achilles repair during a simulated, progressive rehabilitation program.
Knee Surg Sports Traumatol Arthrosc
October 2015