Male Youth Ice Hockey Concussion Incidence in a USA Hockey Membership-Adjusted Population: A Peak in 2011 and the Impact of Major Rule Changes.

OBJECTIVE: To investigate the incidence of youth ice hockey-related concussions preceding and following the implementation of new body-checking and head contact rules by USA hockey in 2011. We hypothesized a decrease in concussions after the rule change. DESIGN: Retrospective analysis. SETTING: United States emergency department (ED) data queried in the National Electronic InjurySurveillance System (NEISS). PATIENTS: National Electronic Injury Surveillance System reported male youth (≤18 years) ice hockey concussion cases from January 1, 2002, to December 31, 2016. In total, 848 players were diagnosed with concussion, representing a national estimate of 17 374 cases. INDEPENDENT VARIABLES: Time, specifically years. MAIN OUTCOME MEASURES: Incidences and incidence rates (measured per 10 000 person-years) of male youth ice hockey concussions. Annual trends were analyzed using descriptive and linear or polynomial regression analysis. RESULTS: The national estimate of youth ice hockey-related concussions seen in US emergency departments (EDs) increased significantly from 656 in 2007 to 2042 in 2011 (P < 0.01). During the same period, their respective incidence increased significantly from 21.8 to 66.8 per 10 000, before dropping through 2016 (P < 0.05). After 2011, concussions decreased from 1965 in 2012 to 1292 in 2016 (P = 0.055). The gap in concussion incidence between the 11 to 12 and 13 to 14 divisions widened after 2011 (before 2011: 41 vs 49 per 10 000 person-years [P = 0.80]; after 2011: 45 and 89, respectively [P < 0.01]). CONCLUSIONS: US EDs experienced a significant increase in youth ice hockey concussion visits from 2007 to 2011. After the 2011 rule changes, concussion visits decreased significantly from 2012 to 2016.

Evaluating success rate and comparing complications of operative techniques used to treat chronic syndesmosis injuries.

PURPOSE: To assess the success rate and complications of the surgical interventions used to manage chronic syndesmosis injuries. METHODS: Multiple online databases were queried to identify studies reporting operative intervention for chronic syndesmosis injuries. RESULTS: Modalities of operative fixation include suture-button fixation, arthroscopy and debridement, as well as arthrodesis. The use of operative treatment is effective; however, more direct comparison studies are necessary to evaluate the efficacy of each treatment. CONCLUSION: Various operative procedures have been used for the management of chronic syndesmotic injuries but further prospective studies are necessary to determine the type of treatment that should be indicated.

Epidemiology and trends of adult ice hockey injuries presenting to United States emergency departments: A ten-year analysis from 2007-2016.

PURPOSE: The adult population is under-represented in existing ice hockey injury studies, despite the number of United States (US) adult ice hockey players increasing from 103,533 in 2007 to 180,400 in 2016 (74%). This study establishes trends in demographics, injury location, and injury type for adult ice hockey players (≥19 years old) in the United States. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried for all ice hockey injuries from January 1, 2007 to December 31, 2016. Cases under age 19 were excluded. Each injury's narrative text field was reviewed to determine mechanism of injury. RESULTS: A total of 1,653 patients, representing an estimated 68,786 ice-hockey related injuries, presented to NEISS-participating US EDs. The most commonly injured body parts were the face (n = 12,432, 18.1%), head (n = 10,201, 14.8%), shoulder (n = 9,654, 14.0%) and ankle (n = 5,389, 7.8%). The most common diagnoses made were laceration (n = 18,153, 26.4%), strain/sprain (n = 12,202, 17.7%), fracture (n = 10,079, 14.7%), contusion (n = 9,283, 13.5%) and concussion (n = 4,794, 7.0%). The most common mechanisms of injury were falling (n = 11,786, 18.7%), puck contact (n = 10,544, 15.3%) and player contact (n = 9,449, 13.7%). Concussions increased from 46 in 2007 to 928 in 2016 (R2 = 0.8, ß = 0.9, p < 0.001). Females (n = 1,852, 32%) had a higher proportion of head injuries than males (n = 8,349, 13.3%) (IPR = 2.4, p < 0.0001). The 50+ year old cohort showed a significant increase in injuries during the study period (n = 146 vs. 982, R2 = 0.75, ß = 0.87, p = 0.001). CONCLUSIONS: Despite changing trends in age and sex-related demographics, the majority of injuries in this population may be preventable with adequate enforcement of protective gear use. Increased education amongst players, coaches, trainers, orthopaedic surgeons and primary care physicians should be encouraged to minimize injuries.

A Histologic Analysis of a Retrieved Specimen 24 Years after Hemiresurfacing for Avascular Necrosis.

Reports of long-term evaluation of the viability of the femoral head after a hemiresurfacing arthroplasty (HRA) are scarce. We report the case of a 41-year-old female with lupus and right HRA (performed 24 years previously for avascular necrosis) that was revised to a total hip arthroplasty for worsening right groin pain due to chondrolysis. We present a histologic evaluation of the resurfaced femoral head retrieved 24 years after HRA. To the authors' knowledge, this is the longest reported histologic follow-up of such a case. There was no evidence of fracture or inflammation and the underlying bone was viable. At 5-year follow-up after the revision, the patient is pain-free, fully functional, and walks without any assistive device.

Anatomical Modifications during the Lateral Transpsoas Approach to the Lumbar Spine. The Impact of Vertebral Rotation.

BACKGROUND: We investigated impact of vertebral axial rotation on neurovascular anatomy in adult spinal deformity (ASD) patients and provided recommendations on the approach based on degree of axial rotation. In order to isolate vertebral rotation (VR) impact from the superimposed degenerative cascade observed in adulthood, adolescent idiopathic scoliosis (AIS) patients were analyzed. METHODS: Magnetic resonance imaging (MRI) scans (L1-S1) from 50 right-convex thoracic (left-convex lumbar) AIS patients were analyzed. At each intervertebral level, VR, lumbar plexus depth (LPD), and vascular structure depth (VSD) were evaluated. Paired t test analyses were used to describe anatomic differences between the concave and convex aspect of our patients' curves. Correlation analysis was used to investigate relationships with soft tissue modifications and VR. RESULTS: Fifty AIS patients (17M, 33F) with mean thoracic Cobb of 50.6° ± 17.0° and mean lumbar Cobb of 41.9° ± 13.0° were included. Mean VR at each level was L1-2 = -6.6°, L2-3 = -7.7°, L3-4 = -6.5°, L4-5 = -4.7°, L5-S1 = -2.6° (negative value denotes clockwise rotation). We found significant differences (P < .05) between concave-convex (right-left) LPD at each level (L1-2 = 3.7 mm, L2-3 = 5.1 mm, L3-4 = 4.2 mm, L4-5 = 2.2 mm, L5-S1 = 2.2 mm). Vascular structure depth was significantly different at L1-L2 (3.2 mm) and L5-S1 (3 mm). Significant correlation was found between increasing VR and concave-convex LPD difference (r = 0.68, P < .001). CONCLUSIONS: This study demonstrates that displacement of the lumbar plexus is tied to the magnitude of VR in patients with AIS. When approaching the lumbar spine, this displacement widens the safe surgical corridor on the convex side and narrows the corridor on the concave side. LEVEL OF EVIDENCE: IV. CLINICAL RELEVANCE: Preoperative review of MRI scans should occur to assess the patient's safe surgical corridor for lateral lumbar interbody fusion (LLIF). Adult spinal deformity surgeons who approach a degenerated spine in patients with progressive AIS in adulthood must carefully plan for patient positioning, neurovascular anatomy, and realignment objectives prior to the day of surgical intervention.

Demographics and rates of surgical arthroscopy and postoperative rehabilitative preferences of arthroscopists from the Arthroscopy Association of North America (AANA).

Survey of 869 arthroscopists regarding joint-specific arthroscopic procedures and postoperative rehabilitative preferences revealed comparable support for use of supervised physical therapy (SPT) and home exercise programs (HEPs) but stronger preference for joint-specific HEP applications (wrist, knee). Among respondents utilizing HEPs, modality of delivery (verbal/handout/web-based) didn't differ by joint, yet only 2.9% utilized web-based HEPs. This is the first known study to identify postoperative rehabilitation preferences. With 1.77 million estimated arthroscopic procedures annually (mean: 325.4 procedures/respondent), this study highlights under-utilization of web-based HEPs. Reliable, web-based HEPs can improve post-arthroscopic outcomes for patients, arthroscopic surgeons, and rehabilitative specialists while being cost efficient.

Combined Labeled Leukocyte and Technicium 99 Sulfur Colloid Bone Marrow Imaging: Differentiating Primary Pyomyositis Pseudotumor from Osteomyelitis and Multiple Bone Infarcts.

A 53 year old-female patient with lupus had undergone a cephalo-medullary nailing for a femur shaft fracture 30 years ago. This was complicated by osteomyelitis, requiring multiple debridement procedures and hardware removal. Recently, she developed a painful soft tissue mass in the same region, which was ultimately diagnosed as pyomyositis. Because of chronic bone changes due to her past history, traditional imaging could not differentiate between osteomyelitis infarction and pseudotumor. A combined indium-labeled leukocyte scan with a technetium-99 sulfur colloid marrow scan ruled out osteomyelitis and guided proper treatment without osseous debridement and thus prevented unnecessary cross-contamination of the bone.

The Effects of Meniscal Geometry on Susceptibility for Meniscal and ACL Injury in Non-Arthritic Knees: A Retrospective Case-Control Study.

Prior studies have not found significant differences in meniscal parameters between patients with meniscal and ligamentous injury and those without. The purpose of this study was to determine whether such relationships exist. Clinical records and magnetic resonance images of three subject groups were reviewed. Group 1 solely had meniscal tears (medial/lateral), Group 2 had meniscal tears with concurrent ACL tears, and Group 3 had healthy knees. The mean age of subjects included was 35.9 years (range 8.2-72.6). The height, width, diagonal, slope, and cross-sectional area for the anterior and posterior horns of the lateral and medial menisci were assessed. Normal distribution of data was confirmed by the Shapiro-Wilk test and analysis of variance with a post hoc Tukey's test was used to assess potential differences. p < 0.05 was set as the level of significance. There was no difference between the meniscal slopes of patients with and without meniscal tears (p = 0.77-1.0). Meniscal height (p = 0.0001-0.024) and width (p = 0.0001-0.046) demonstrated significant differences in all horns. Cross-sectional area was larger in the torn group (p = 0.0001-0.012). To compare intact and torn menisci, a logistical regression model was used and found to be significantly different from the constant model (p < 0.0001). Predictive success was 80.5%. A logistical regression model was used comparing undamaged menisci with torn menisci with accompanying anterior cruciate ligament (ACL) tear and was significant (p < 0.0001). A larger cross-sectional meniscal area in both the anterior and posterior horns of both menisci was a risk factor for isolated meniscal tears and combined meniscal and ACL tears. It has been postulated that certain demographic variables, such as gender, age, and body mass index, may be risk factors associated with ACL and meniscal injuries. However, the relationship between intrinsic morphology, namely meniscal size and shape, and risk of injury is unclear. The majority of studies have focused on meniscal morphology/geometry and its association with degenerative tears in patients with end-stage osteoarthritis rather than on acute meniscoligamentous injury. In this study of non-arthritic knees, a larger cross-sectional meniscal area in both the anterior and posterior horns of both menisci was a risk factor for having both an isolated meniscal tear as well as a combined meniscal and ACL tear. With advances in the field of meniscal repair, particularly with allograft procedures, more attention should be paid to meniscal cross-sectional area because it may play a role in the natural history of knee injury.

Regional Variations in Shear Strength and Density of the Human Thoracic Vertebral Endplate and Trabecular Bone.

BACKGROUND: Previous studies investigated the overall mechanical strength of the vertebral body; however, limited information is available on the biomechanical properties of different regions within the vertebral endplate and cancellous bone. In addition, the correlation between mechanical strength and various density measurements has not been studied yet. METHODS: Thoracic (T10) vertebrae were harvested from fifteen human cadaveric spines (average age: 77 years old). Twelve cylindrical cores of 7.2 mm (diameter) by 3.2 mm (height) were prepared from each vertebral body. Shear was produced using a stainless steel tubular blade and measured with a load cell from a mechanical testing machine. Optical and bulk densities were calculated before mechanical testing. Apparent, material, and ash densities were measured after testing. RESULTS: Material density and shear strength increased from anterior to lateral regions of both endplate and cancellous bone. Endplate shear strength was significantly lower in the anterior (0.52 ± 0.08 MPa) than in the lateral region (2.72 ± 0.59 MPa) (p=0.017). Trabecular bone maximum load carrying capacity was 5 times higher in the lateral (12 ± 2.74 N) (p=0.09) and 4.5 times higher in the central (10 ± 2.24 N) (p=0.2) than in the anterior (2 ± 0.60 N) regions. Mechanical strength positively correlated with ash density, and even moreso with material density. CONCLUSION: Shear strength was the lowest at the anterior region and highest at the lateral region for both endplate and cancellous bone. Material density had the best correlation with mechanical strength. Newer spinal implants could optimize the loading in the lateral aspects of both endplate and cancellous bone to reduce the likelihood of screw loosening and the subsidence of disc replacement devices. This study was reviewed by the SUNY Downstate Medical Center IRB Committee; IRB#: 533603-2.

Acromioclavicular joint reconstruction using a tendon graft: a biomechanical study comparing a novel "sutured throughout" tendon graft to a standard tendon graft.

BACKGROUND: With a recurrence rate of over 30%, techniques that offer stronger acromioclavicular (AC) joint reconstruction through increased graft strength may provide longevity. The purpose of our study was to determine the biomechanical strength of a novel tendon graft sutured throughout compared to a native tendon graft in Grade 3 anatomical AC joint reconstruction. METHODS: For this in vitro experiment, nine paired (n = 18) embalmed cadaveric AC joints of three males and six females (age 86 years, range 51-94 years) were harvested. Anatomic repair with fresh bovine Achilles tendon grafts without bone block was simulated. Specimens were divided into two groups; with group 1 using grafts with ultra-high molecular-weight polyethylene (UHMWPE) suture ran throughout the entire length. In group 2, reconstruction with only native allografts was performed. The distal scapula and humerus were casted in epoxy compound and mounted on the mechanical testing machine. Tensile tests were performed using a mechanical testing machine at the rate of 50 mm/min. Maximum load and displacement to failure were collected. RESULTS: The average load to failure was significantly higher for group 1 compared to group 2, with mean values of 437.5 N ± 160.7 N and 94.4 N ± 43.6 N, (p = 0.001). The average displacement to failure was not significantly different, with 29.7 mm ± 10.6 mm in group 1 and 25 mm ± 9.1 mm in group 2 (p = 0.25). CONCLUSION: We conclude that a UHMWPE suture reinforced graft can provide a 3.6 times stronger AC joint reconstruction compared to a native graft.

Revision Surgery for "Real" Recurrent Lumbar Disk Herniation: A Systematic Review.

STUDY DESIGN: A systematic review. OBJECTIVE: To systematically review the previous literature regarding revision surgery for real recurrent lumbar disk herniation. SUMMARY OF BACKGROUND DATA: "Real" recurrent lumbar disk herniation means the presence of herniated disk material at the same level and side as the primary disk herniation. If conservative treatment fails, revision surgery, a major concern, is indicated. It is important for both patients and spine surgeons to understand epidemiology trends and outcomes of revision surgery for real recurrent lumbar disk herniation (real-RLDH). METHODS: The electronic databases PubMed, the Cochrane library, and EMBASE were queried for English articles regarding revision surgery for real-RLDH, published between January 1980 and May 2014. The incidence, interval between primary and revision surgery, risk factors, surgery type, complications, and clinical outcomes of revision surgery for real-RLDH were summarized. RESULTS: The reported incidence of revision surgery, specifically for real-RLDH, lies between 1.4% and 11.4%. The complication rate is reported between 0% and 34.6%, with dural tear being the most common complication. Previous studies revealed that satisfactory or successful clinical outcome was achieved in 60%-100% of patients after revision surgery for real-RLDH. Several studies reported similar clinical outcomes between primary and revision surgery. CONCLUSIONS: The incidence of revision surgery for real-RLDH is relatively low. It is essential to pay careful attention to prevent a dural tear. Patients may expect clinical outcomes similar to those following primary discectomy.

Subchondral Calcium Phosphate is Ineffective for Bone Marrow Edema Lesions in Adults With Advanced Osteoarthritis.

BACKGROUND: Injury to subchondral bone is associated with knee pain and osteoarthritis (OA). A percutaneous calcium phosphate injection is a novel approach in which subchondral bone marrow edema lesions are percutaneously injected with calcium phosphate. In theory, calcium phosphate provides structural support while it is gradually replaced by bone. However, little clinical evidence supports the efficacy of percutaneous calcium phosphate injections. QUESTIONS/PURPOSES: We asked: (1) Does percutaneous calcium phosphate injection improve validated patient-reported outcome measures? (2) What proportion of patients experience failure of treatment (defined as a low score on the Tegner Lysholm Knee Scoring Scale)? (3) Is there a relationship between outcome and age, sex, BMI, and preoperative grade of OA? METHODS: Between September 2012 and January 2014, we treated 33 patients with percutaneous calcium phosphate injections. Twenty-five satisfied our study inclusion criteria; of those, three patients were lost to followup and 22 (88%; 13 men, nine women) with a median age of 53.5 years (range, 38-70 years) were available for retrospective chart review and telephone evaluation at a minimum of 6 months (median, 12 months; range, 6-24 months). Our general indications for this procedure were the presence of subchondral bone marrow edema lesions observed on MR images involving weightbearing regions of the knee associated with localized pain on weightbearing and palpation and failure to respond to conservative therapy (> 3 months). Patients with pain secondary to extensive nondegenerative meniscal tears with a flipped displaced component at the level of bone marrow edema lesions, or with mechanical axis deviation greater than 8° were excluded. All patients had Grades III or IV chondral lesions (modified Outerbridge grading system for chondromalacia) overlying MRI-identified subchondral bone marrow edema lesions. Percutaneous calcium phosphate injection was performed on the medial tibial condyle (15 patients), the medial femoral condyle (five patients), and the lateral femoral condyle (two patients). Concomitant partial meniscectomy was performed in 18 patients. Preoperative and postoperative scores from the Knee Injury and Arthritis Outcome Score (KOOS) and the Tegner Lysholm Knee Scoring Scale were analyzed. RESULTS: For patients available for followup, the outcome scores improved after treatment. The KOOS improved from a mean of 39.5 ± 21.8 to 71.3 ± 23 (95% CI, 18.6-45.2; p < 0.001) and the Tegner and Lysholm score from 48 ± 15.1 to 77.5 ± 20.6 (95% CI, 18.8-40.2; p < 0.001). However, seven of the 22 patients had poor clinical outcomes as assessed by the Tegner Lysholm Knee Scoring Scale, whereas three had fair results, five had good results, and seven had excellent results. The postoperative Tegner Lysholm score was inversely related to the preoperative Kellgren-Lawrence OA grade (R(2) = 0.292; F (1.20) = 9.645; p = 0.006). We found no relationship between outcome scores and age, sex, or BMI. CONCLUSIONS: In a study that would have been expected to present a best-case analysis (short-term followup, loss to followup of patients with potentially unsatisfactory results, and use of invasive cotreatments including arthroscopic débridements), we found that percutaneous calcium phosphate injection in patients with symptomatic bone marrow edema lesions of the knee and advanced OA yielded poor results in a concerning proportion of our patients. Based on these results, we advise against the use of percutaneous calcium phosphate injections for patients with advanced osteoarthritic changes. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Current Concepts in Sports-Related Concussion.

Traumatic brain injury, specifically concussion, is prevalent in contact sports. In the United States (US) each year, 170 million adults participate in physical recreational activities, and 38 million children and adolescents participate in organized sports. The Centers for Disease Control estimate that in this group ~1.6 to 3.8 million concussions occur annually. Recent class-action lawsuits in the US filed by professional athletes against their respective leagues allege negligence in protecting them from concussions, and this has contributed to the attention received in the popular media. In response, concussion-related publications have increased exponentially during the past several years. Recent studies have challenged earlier assumptions that the effects of concussion are transient. Stronger links between concussion and neurodegenerative processes such as Alzheimer's disease-like conditions, depression, and heightened risk for suicide are being elucidated. In this article, we explore the current knowledge on concussion, including pathophysiology, management, and long-term effects. We conclude that more evidence-based results regarding guidelines for diagnosis, treatment, and return to play (RTP) are needed and should be the focus of future investigations. Attributing the etiology of certain neurodegenerative conditions to a history of concussion has been suggested in the current literature, but additional quantitative data regarding the pathophysiology and causality are needed as well. Bioengineers can have an important role in measuring the dynamic forces encountered during head impacts and their effects on the brain. These results can be effective in designing better helmets as well as improved playing surfaces to reduce the impact of such injuries. At this time, we believe that groups of people with heightened risk for concussion should be followed closely during longer periods of time and compared to matched controls. Such long-term studies are urgently needed to develop appropriate guidelines for safety and protect our young and adult athletes in the future.