Limited Return to Preinjury Performance in NCAA Division I American Football Players With Hamstring Injuries.

Background: Hamstring strains are common among elite athletes, but their effect on return to the same level of play in American football has been incompletely characterized.

Purpose: Data on National Collegiate Athletics Association Division I college football players with acute hamstring strains were gathered to identify the effects these injuries have on both return to play and athletic performance regarding velocity, workload, and acceleration.

Study Design: Case Series; Level of evidence, 4.

Effect of Age and Body Mass Index on Time to Advanced Imaging and Surgery in Young Athletes With Anterior Cruciate Ligament Injury.

Background: In young athletes with anterior cruciate ligament (ACL) injury, increased times from injury to magnetic resonance imaging (MRI) and injury to surgery can lead to the accrual of new injuries over time.

Purpose: To determine the patient characteristics associated with differences in timing between injury, MRI, and surgery in young athletes with ACL tears.

Study Design: Case-control study; Level of evidence, 3.

Effect of Increased Time to Surgery on the Ability of MRI to Rule Out Medial Meniscal Tears in Young Athletes With ACL Injury.

Background: The prevalence of meniscal tears in patients with anterior cruciate ligament (ACL) injury increases with extended time between injury and ACL reconstruction.

Purpose/hypothesis: The purpose of this study was to determine if there is a relationship between time from magnetic resonance imaging (MRI) to ACL reconstruction and the predictive value of MRI to diagnose meniscal tears in the young active population. It was hypothesized that increased time between MRI and ACL reconstruction would lead to a decrease in the negative predictive value of MRI in diagnosing meniscal tears, as more injuries may accrue over time in the ACL-deficient knee.

Effect of Delayed Anterior Cruciate Ligament Reconstruction on Repair of Concomitant Medial Meniscus Tears in Young Athletes.

Background: Delayed anterior cruciate ligament (ACL) reconstruction (ACLR) is associated with an increased risk of meniscal injury. Limited data are available regarding the relationship between surgical delay and meniscal repairability in the setting of ACLR in young patients.

Purpose: To determine whether time from ACL injury to primary ACLR was associated with the incidence of medial and/or lateral meniscal repair in young athletes who underwent meniscal treatment at the time of ACLR.

Review of human supraspinatus tendon mechanics. Part I: fatigue damage accumulation and failure.

Repetitive stress injuries to the rotator cuff, and particularly the supraspinatus tendon (SST), are highly prevalent and debilitating. These injuries typically occur through the application of cyclic load below the threshold necessary to cause acute tears, leading to accumulation of incremental damage that exceeds the body's ability to heal, resulting in decreased mechanical strength and increased risk of frank rupture at lower loads. Consistent progression of fatigue damage across multiple model systems suggests a generalized tendon response to overuse.

Review of human supraspinatus tendon mechanics. Part II: tendon healing response and characterization of tendon health.

Overuse injuries of the rotator cuff, particularly of the supraspinatus tendon (SST), are highly prevalent and debilitating in work, sport, and daily activities. Despite the clinical significance of these injuries, there remains a large degree of uncertainty regarding the pathophysiology of injury, optimal methods of nonoperative and operative repair, and how to adequately assess tendon injury and healing. The tendon response to fatigue damage resulting from overuse is different from that of acute rupture and results in either an adaptive (healing) or a maladaptive (degenerative) response.

Anterior Cruciate Ligament Reconstruction with 4-Strand Hamstring Tendon Construct May be Biomechanically Superior to 5-Strand Hamstring Tendon Construct When Using Femoral Suspensory Fixation.

Purpose: To compare stiffness, strain, and load to failure of 4- versus 5-strand hamstring anterior cruciate ligament reconstruction human tendon allografts with femoral suspensory and tibial interference screw fixation.

Methods: Allograft hamstring tendons were used to create 10 four-strand (4S) and 10 five-strand (5S) grafts. Grafts were fixed to a uniaxial electromechanical load system via a femoral cortical suspensory button and a bioabsorbable interference screw in bone analogue.

Diagnostic performance of MRA in abduction and external rotation position in the detection of glenoid labral lesions: a systematic review and meta-analysis.

Objective: To compare the diagnostic performance of direct magnetic resonance arthrography (MRA) for labral lesions during conventional, abduction and external rotation (ABER), conventional plus abduction, and external rotation (ABER) positioning by using a systematic review and meta-analysis.

Materials And Methods: A comprehensive literature search was performed on the two main concepts of magnetic resonance arthrography: extremity position and labral lesions. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR arthrography in ABER and conventional position alone or combined for the diagnosis of labral lesions by using surgical findings as the reference standard.

Radiological Society of North America/Quantitative Imaging Biomarker Alliance Shear Wave Speed Bias Quantification in Elastic and Viscoelastic Phantoms.

Objectives: To quantify the bias of shear wave speed (SWS) measurements between different commercial ultrasonic shear elasticity systems and a magnetic resonance elastography (MRE) system in elastic and viscoelastic phantoms.

Methods: Two elastic phantoms, representing healthy through fibrotic liver, were measured with 5 different ultrasound platforms, and 3 viscoelastic phantoms, representing healthy through fibrotic liver tissue, were measured with 12 different ultrasound platforms. Measurements were performed with different systems at different sites, at 3 focal depths, and with different appraisers.

Management of Glenohumeral Joint Osteoarthritis.

The Management of Glenohumeral Joint Osteoarthritis Evidence-Based Clinical Practice Guideline is based on a systematic review of published studies for the treatment of glenohumeral joint osteoarthritis. The purpose of this clinical practice guideline is to address the management of patients with glenohumeral joint osteoarthritis. It is not intended to address the management of glenohumeral joint arthritis from etiologies other than osteoarthritis (ie, rheumatoid arthritis, inflammatory arthritis, posttraumatic arthritis, osteonecrosis, rotator cuff tear arthroplasty, capsulorrhaphy arthroplasty, and postinfections arthroplasty) This guideline contains 13 recommendations to assist all qualified and appropriately trained healthcare professionals involved in the management of glenohumeral joint osteoarthritis.

Biomechanical Effects of Blood Flow Restriction Training after ACL Reconstruction.

Introduction: After anterior cruciate ligament reconstruction surgery, returning the knee to previous levels of strength and function is challenging, with the failure to do so associated with an increased risk of reinjury and long-term degenerative problems. Blood flow restriction (BFR) is gaining popularity as a rehabilitation technique; however, its effects on the mechanics of these exercises have not been fully explored. In this study, we aimed to determine the acute effects of BFR on the performance of a step-up exercise protocol and to assess the acceptability of the technique.

What Is the Survivorship After Hip Arthroscopy for Femoroacetabular Impingement? A Large-database Study.

Background: Patients with femoroacetabular impingement (FAI) may experience lasting clinical improvement after hip arthroscopy; however, some patients will still eventually undergo early conversion to THA due to unresolved symptoms and progression of arthritis. However, the risk of this has been only incompletely characterized in prior studies.

Questions/purposes: Using a large healthcare claims database over a 5-year period (2011-2016), we asked: (1) What is the survivorship free from THA after arthroscopic osteoplasty performed for FAI? (2) What identifiable demographic factors and patient characteristics are associated with early conversion to THA after hip arthroscopy performed for FAI?

Methods: We included all patients who underwent hip arthroscopy for FAI, between the ages of 12 years and 63 years, with 3 months of claims data before hip arthroscopy and minimum 2-year follow-up.

The Pull Test: A Dynamic Test to Confirm Hip Microinstability.

Purpose: To define a distraction distance (pull length) cut-off that would differentiate those patients with hip microinstability and those without the disorder, called the Pull-Out Test.

Methods: In total, 100 consecutive patients undergoing hip arthroscopy were included in the study. Patients were separated into a hip microinstability group (HMI) and non-hip microinstability group (NHI) based on the results of Beighton's score, the abduction-extension-external rotation test, hip extension-external rotation examination, and the prone instability test.

Monitoring changes in knee surface morphology after anterior cruciate ligament reconstruction surgery using 3Dsurface scanning.

Study Design: Prospective case series.

Background: After surgical reconstruction of the anterior cruciate ligament, recovery to pre-injury levels of knee function is challenging. Postoperative edema and muscle atrophy are common roadblocks to full function and are evident in changes to the surface morphology of the knee.

THE USE OF MICROSOFT KINECT ™ FOR ASSESSING READINESS OF RETURN TO SPORT AND INJURY RISK EXERCISES: A VALIDATION STUDY.

Introduction: Assessing readiness of return to sport after procedures such as anterior cruciate ligament (ACL) reconstruction is a complex process, complicated by the pressures that athletes face in returning to sport as quickly as possible. Advances in motion analysis have been able to demonstrate movements that are risk factors for initial ACL injury and subsequent reinjury after reconstruction. An inexpensive, objective measure is needed to determine when athletes are ready to return to sport after ACL reconstruction.

The Menstrual Cycle May Affect Anterior Knee Laxity and the Rate of Anterior Cruciate Ligament Rupture: A Systematic Review and Meta-Analysis.

Background: Women have a higher risk of anterior cruciate ligament (ACL) tears than men, the causes of which are multifactorial. The menstrual cycle and its hormonal effect on the knee may contribute to knee laxity and ACL injury. This work reviewed published studies examining the effects of the phases of the menstrual cycle on anterior knee laxity and the rate of ACL tears.

Preoperative MRI for the Multiligament Knee Injury: What the Surgeon Needs to Know.

The multiligament knee injury is devastating and potentially limb threatening. Preoperative magnetic resonance imaging for the evaluation of the multiligament knee injury is an invaluable clinical tool, and when the radiologist is familiar with how certain injury patterns influence management, optimal outcomes can be achieved. We provide a detailed description of the relationship between salient imaging features of the multiligament knee injury, focusing on the preoperative magnetic resonance imaging, and their influence on clinical decision-making.

Nanotopographic cues and stiffness control of tendon-derived stem cells from diverse conditions.

Background: Tendon-derived stem cells (TDSCs) are key factors associated with regeneration and healing in tendinopathy. The aim of this study was to investigate the effects of mechanical stiffness and topographic signals on the differentiation of TDSCs depending on age and pathological conditions.

Materials And Methods: We compared TDSCs extracted from normal tendon tissues with TDSCs from tendinopathic Achilles tendon tissues of Sprague Dawley rats in vitro and TDSCs cultured on nanotopographic cues and substrate stiffness to determine how to control the TDSCs.

Comparison of medial and lateral posterior femoral condyle articular cartilage wear patterns.

Background: While degenerative changes to the articular cartilage of the anterior and distal portions of the femoral condyles have been well studied in the literature, the changes that occur on the posterior femoral condyle are not as clear. The purpose of this study was to assess the difference in articular cartilage thickness between the medial and lateral posterior femoral condyles in knees undergoing unicompartmental knee arthroplasty.

Methods: A retrospective review of prospectively gathered data on 107 consecutive patients undergoing unicompartmental knee arthroplasty performed by a single surgeon was performed.