American Journal of Sports Medicine

BACKGROUND: An athlete's preexisting psychological factors may influence the incidence and/or severity of sports-related concussions (SRCs). PURPOSE: To determine if emotional states, personality traits, temperament, life stressors, and explanatory styles (optimism vs pessimism) influence the incidence and severity of SRCs in athletes. STUDY DESIGN: Systematic review. METHODS: A systematic literature search of multiple major medical reference databases was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines...

BACKGROUND: Concern for head injuries is widespread and has been reported by the media to be the number one cause of decreased participation in football among the American youth population. Identifying player mechanisms associated with intentional, or purposeful, head impacts should provide critical data for rule modifications, educational programs, and equipment design. PURPOSE: To investigate the frequency of intentional and unintentional head impacts and to examine the player mechanisms associated with intentional high-magnitude head impacts by comparing the impact mechanism distributions among session type, player position, and ball possession...

BACKGROUND: Treatment of anterior cruciate ligament (ACL) injuries in the adolescent population continues to be complicated by an unacceptably high rate of secondary ACL injury. PURPOSE: To describe the failure rate and outcomes after a hybrid pediatric ACL reconstruction (ACLR) employing transphyseal hamstring (TPH) autograft combined with an extra-articular technique using an iliotibial band (ITB) autograft. STUDY DESIGN: Case series; Level of evidence, 4...

BACKGROUND: Meniscal tears, including tears at the root attachment, have been associated with tears of the anterior cruciate ligament (ACL) in both primary and revision settings. However, there is a paucity of literature reporting the healing rates of meniscal repair during 2-stage revision ACL reconstruction (ACLR). PURPOSE: To evaluate the healing rates of meniscal repairs performed during 2-stage revision ACLR in ACL-deficient knees and to report the incidence of meniscus root tears in patients undergoing primary ACLR as compared with revision ACLR...

BACKGROUND: The incidence of contralateral anterior cruciate ligament (CACL) injuries after recovery from a first-time anterior cruciate ligament (ACL) disruption is high in women; however, little is known about the risk factors associated with this trauma. HYPOTHESIS: Patient characteristics, strength, anatomic alignment, and neuromuscular characteristics of the contralateral uninjured leg at the time of the first ACL trauma are associated with risk of subsequent CACL injury, and these risk factors are distinct from those for a first-time ACL injury...

BACKGROUND: For active patients undergoing periacetabular osteotomy (PAO), returning to and maintaining a high level of activity postoperatively is a priority. PURPOSE: To evaluate the maintenance of activity levels at midterm follow-up in active patients treated with PAO for symptomatic acetabular dysplasia. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients who underwent PAO for symptomatic acetabular dysplasia between June 2006 and August 2013 were identified by a retrospective review of our prospective longitudinal institutional Hip Preservation Database...

BACKGROUND: Bilateral hip symptoms are common in athletes, and athletes may require treatment with bilateral hip arthroscopy. Return-to-sport (RTS) rates in competitive athletes after unilateral procedures have been reported at 74% to 93%; however, RTS rates after bilateral hip arthroscopy are still unknown. PURPOSE/HYPOTHESIS: The purpose was to determine rate of RTS in competitive athletes undergoing bilateral hip arthroscopy and report minimum 1-year patient-reported outcomes (PROs) for this cohort...

BACKGROUND: The clinical importance of meniscal ramp lesions in patients with anterior cruciate ligament (ACL) tear has emerged as a major issue. However, the diagnostic accuracy of magnetic resonance imaging (MRI) for detecting ramp lesions has a wide range. PURPOSE: To perform a systematic review and meta-analysis of the diagnostic performance of MRI for diagnosing ramp lesion in patients with ACL tear. STUDY DESIGN: Systematic review and meta-analysis...

BACKGROUND: In shoulders with traumatic anterior instability, a bipolar bone defect has recently been recognized as an important indicator of the prognosis. PURPOSE: To investigate the influence of bipolar bone defects on postoperative recurrence after arthroscopic Bankart repair performed at primary instability. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The study group consisted of 45 patients (45 shoulders) who underwent arthroscopic Bankart repair at primary instability before recurrence and were followed for at least 2 years...

BACKGROUND: Autologous osteochondral transplantation (AOT) has been shown to be a viable treatment option for large osteochondral lesions of the talus. However, there are limited data regarding the management of large lesions in an athletic population, notably with regard to return to sport. Our investigation focused on assessing both qualitative and quantitative outcomes in the high-demand athlete with large (>150 mm2 ) lesions. HYPOTHESIS: AOT is a viable option in athletes with large osteochondral lesions and can allow them to return to sport at their preinjury level...

BACKGROUND: Cell-based therapy for cartilage repair is a promising approach and is becoming an established technique. Yet, there is no consensus on the optimal cell source. PURPOSE: To provide a donor-matched quantitative comparison of the connective tissue progenitors (CTPs) derived from cartilage (Outerbridge grade 1-3 [G1-2-3]), bone marrow aspirate concentrate (BMC), infrapatellar fat pad (IPFP), synovium, and periosteum with respect to (1) cell concentration ([Cell], cells/mL), (2) CTP prevalence (PCTP , colonies per million cells), and (3) biological performance based on in vitro proliferation potential (cells per colony) colony density, and differentiation potential (expression of negatively charged extracellular matrix: glycosaminoglycan-rich extra cellular matrix [GAG-ECM])...

BACKGROUND: Aberrant frontal-plane hip and pelvis kinematics have been frequently observed in runners with patellofemoral pain (PFP). Gait retaining interventions have been shown to improve running kinematics and may therefore be beneficial in runners with PFP. PURPOSE: To investigate whether a 10% increase in the running step rate influences frontal-plane kinematics of the hip and pelvis as well as clinical outcomes in runners with PFP. STUDY DESIGN: Case series; Level of evidence, 4...

BACKGROUND: The biomechanical function of the anterolateral structure (ALS), which includes the anterolateral joint capsule and anterolateral ligament (ALL), remains a topic of debate. HYPOTHESIS: The ALS contributes to knee joint stability during the Lachman test and the pivot-shift test in anterior cruciate ligament (ACL)-deficient knees. STUDY DESIGN: Controlled laboratory study. METHODS: Fourteen fresh-frozen hemipelvis lower limbs were used...

BACKGROUND: Recently reported anterolateral structure reconstructions (ALSRs) to augment intra-articular anterior cruciate ligament reconstruction (ACLR) use various femoral attachment sites, and their biomechanical effects are still unknown. HYPOTHESIS: ALSR concomitant with ACLR would control anterolateral rotational instability better than ACLR alone, and if ALSR had different femoral attachment sites, there would be different effects on its control of anterolateral rotational instability...

BACKGROUND: Although numerous techniques of reconstruction of the medial ulnar collateral ligament (mUCL) have been described, limited evidence exists on the biomechanical implication of changing the ulnar tunnel position despite the fact that more recent literature has clarified that the ulnar footprint extends more distally than was appreciated in the past. PURPOSE: To evaluate the size and location of the native ulnar footprint and assess valgus stability of the medial elbow after UCL reconstruction at 3 ulnar tunnel locations...

BACKGROUND: Sport-related concussions (SRCs) are associated with short-term disablement, characterized as increased concussion symptoms and lower health-related quality of life (HRQoL). However, there are limited longitudinal data detailing how an SRC affects disablement beyond short-term injury recovery. PURPOSE: To longitudinally assess the effect of SRCs on symptoms and HRQoL in high school athletes through the 12 months after injury. STUDY DESIGN: Cohort study; Level of evidence, 2...

BACKGROUND: The preoperative number of dislocations has been previously proved to be a major factor influencing the results after Bankart repair with more preoperative dislocations correlated with higher recurrence rates and more reoperations. This could possibly be because of the lower quality of the tissue repaired during the procedure after multiple dislocations. On the other hand, the Latarjet procedure does not "repair" but rather reconstructs and augments the anterior glenoid...

BACKGROUND: Although the femoral tunnel position is crucial to anatomic single-bundle anterior cruciate ligament (ACL) reconstruction, the recommendations for the ideal femoral footprint position are mostly based on cadaveric studies with small sample sizes, elderly patients with unknown ACL status, and 2-dimensional techniques. Furthermore, a potential difference in the femoral ACL footprint position and ACL orientation between ACL-ruptured and ACL-intact knees has not been reported in the literature...

BACKGROUND: Large radial tears of the meniscus involving the avascular region can compromise meniscal function and result in poor healing and subsequent osteochondral degeneration. Augmentation of surgical repairs with adipose-derived stromal vascular fraction (SVF), which contains mesenchymal stromal cells, may improve meniscal healing and preserve function (ie, chondroprotection). PURPOSES: (1) To develop a goat model of a radial meniscal tear with resulting osteoarthritis and (2) to explore the efficacy of a 1-step procedure utilizing infrapatellar fat pad-derived SVF cells seeded in a photocrosslinkable hydrogel to enhance meniscal healing and mitigate osteochondral degeneration...

BACKGROUND: Partial avulsions of the proximal hamstring origin remain a challenging problem with nonoperative treatments frequently providing limited success. The literature is limited regarding the outcomes of operative management in the active and athletic population. HYPOTHESIS: Surgical fixation of proximal hamstring ruptures will have favorable outcomes at midterm follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 64 patients with partial avulsions of the proximal hamstring origin treated with surgical fixation by a single surgeon were reviewed at a 2-year minimum follow-up...