Perceived vs. true glenoid anchor placement: a cadaveric comparison of the beach chair and lateral position.

Purpose: To explore whether patient position influences a surgeon's ability to accurately judge anchor position on the glenoid.

Materials And Methods: Two anchors were inserted into the glenoid of 8 shoulders. Arthroscopic videos were taken from 3 views (posterior beach chair [pBC], posterior lateral decubitus [pLD], and anterosuperolateral decubitus [asLD]).

Three-Year Longitudinal Fitness Tracking in Top-Level Competitive Youth Ice Hockey Players.

Cordingley, DM, Sirant, L, MacDonald, PB, and Leiter, JR. Three-year longitudinal fitness tracking in top-level competitive youth ice hockey players. J Strength Cond Res 33(11): 2909-2912, 2019-The purpose of this retrospective review was to report the physical and physiological development of top-level competitive male youth hockey players for 3 consecutive years (13, 14, and 15 years of age).

Physical fitness of medical residents: Is the health of surgical residents at risk?

Background: Postgraduate medical residency programs are laborious and timeintensive, and can be physically, intellectually and emotionally demanding. These working conditions may lead to the neglect of personal health and well-being. The objective of this study was to compare the anthropometric and fitness characteristics of surgical and nonsurgical medical residents.

Development of Anaerobic Fitness in Top-Level Competitive Youth Ice Hockey Players.

Leiter, JR, Cordingley, DM, and MacDonald, PB. Development of anaerobic fitness in top-level competitive youth ice hockey players. J Strength Cond Res 32(9): 2612-2615, 2018-Ice hockey is a physiologically complex sport involving both the anaerobic and aerobic energy systems.

Altered Satellite Cell Responsiveness and Denervation Implicated in Progression of Rotator-Cuff Injury.

Background: Rotator-cuff injury (RCI) is common and painful; even after surgery, joint stability and function may not recover. Relative contributions to atrophy from disuse, fibrosis, denervation, and satellite-cell responsiveness to activating stimuli are not known.

Methods And Findings: Potential contributions of denervation and disrupted satellite cell responses to growth signals were examined in supraspinatus (SS) and control (ipsilateral deltoid) muscles biopsied from participants with RCI (N = 27).

Aerobic Development of Elite Youth Ice Hockey Players.

Ice hockey is a physiologically complex sport requiring aerobic and anaerobic energy metabolism. College and professional teams often test aerobic fitness; however, there is a paucity of information regarding aerobic fitness of elite youth players. Without this knowledge, training of youth athletes to meet the standards of older age groups and higher levels of hockey may be random, inefficient, and or effective.

Atrophy, inducible satellite cell activation, and possible denervation of supraspinatus muscle in injured human rotator-cuff muscle.

The high frequency of poor outcome and chronic pain after surgical repair of shoulder rotator-cuff injury (RCI) prompted this study to explore the potential to amplify muscle regeneration using nitric oxide (NO)-based treatment. After preoperative magnetic resonance imaging (MRI), biopsies of supraspinatus and ipsilateral deltoid (as a control) were collected during reparative surgery for RCI. Muscle fiber diameter, the pattern of neuromuscular junctions observed with alpha-bungarotoxin staining, and the γ:ε subunit ratio of acetylcholine receptors in Western blots were examined in tandem with experiments to determine the in vitro responsiveness of muscle satellite cells to activation (indicated by uptake of bromodeoxyuridine, BrdU) by the NO-donor drug, isosorbide dinitrate (ISDN).

Accuracy and reliability of determining the isometric point of the knee for multiligament knee reconstruction.

Purpose: To compare the accuracy and reliability of the anatomic and radiographic techniques for identifying the isometric point of the knee.

Methods: Only four specimens were used; however, eight experienced multiligament knee injury surgeons were recruited to address this limitation. Surgeons estimated the isometric point (EIP) on the medial and lateral sides using an anatomic and radiographic method.

Lower body positive pressure: an emerging technology in the battle against knee osteoarthritis?

Background: Knee osteoarthritis (OA) is the most prevalent medical condition in individuals over the age of 65 years, and is a progressive joint degenerative condition with no known cure. Research suggests that there is a strong relationship between knee pain and loss of physical function. The resulting lifestyle modifications negatively impact not only disease onset and progression but also overall health, work productivity, and quality of life of the affected individual.

Long-term follow-up of ACL reconstruction with hamstring autograft.

Purpose: To investigate the differences in the incidence and severity of knee osteoarthritis (OA), joint space narrowing, knee laxity, and knee flexion and extension strength between an anterior cruciate ligament (ACL)-reconstructed knee and the contralateral non-reconstructed limb.

Methods: Retrospective case series of patients from a single surgeon that had an ACL reconstruction with a semitendinosus/gracilis autograft more than 12 years ago. Outcome measures included radiographic analysis, International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), KT-1000, Tegner Activity Level Scale, Lysholm Knee Score, ACL quality of life score (ACL-QOL) and knee flexor/extensor strength.

Validation of a global assessment of arthroscopic skills in a cadaveric knee model.

Purpose: The purpose of this study was to determine whether a global assessment of arthroscopic skills was valid for blinded assessment of cadaveric diagnostic knee arthroscopy.

Methods: A global skills assessment for arthroscopy was created using a published theory of the development of expertise. Faculty surgeons, fellows, and residents were consented and enrolled in this institutional review board-approved validation study.

The internal validity of arthroscopic simulators and their effectiveness in arthroscopic education.

Purpose: The purpose of this systematic review was to identify standard procedures for the validation of arthroscopic simulators and determine whether simulators improve the surgical skills of users.

Methods: Arthroscopic simulator validation studies and randomized trials assessing the effectiveness of arthroscopic simulators in education were identified from online databases, as well as, grey literature and reference lists. Only validation studies and randomized trials were included for review.

Intrinsic stresses on bone and cartilage in the normal and anterior cruciate ligament-reconstructed knee before and after a half marathon: a magnetic resonance imaging analysis.

Objective: To investigate intrinsic changes of the anterior cruciate ligament-reconstructed and control (contralateral) knees after a half marathon.

Design: Prospective case series.

Setting: Sports Medicine Clinic.

Nitric oxide and voluntary exercise together promote quadriceps hypertrophy and increase vascular density in female 18-mo-old mice.

Age-related sarcopenia reduces the size, strength, and function of muscle, and the diameter of muscle fibers. It also disrupts the dystrophin-glycoprotein complex, dislocating nitric oxide synthase 1 (NOS-1) and reducing sarcolemmal integrity. This study of quadriceps muscle in 18-mo-old mice showed that NO-donor treatment with isosorbide dinitrate (I) for 6 wk, in combination with voluntary exercise for 3 wk, increased muscle mass by 25% and stimulated cell proliferation.

Exercise-induced muscle growth is muscle-specific and age-dependent.

Introduction: Sarcopenia, and the importance of satellite cells (SCs) in muscle growth led us to examine the effects of exercise and age on SC activation and gene expression.

Methods: Eight- and 18-month-old mice were either sedentary or underwent 3 weeks of exercise (N = 24). Body mass, distance traveled, and grip strength were recorded at weekly intervals.

Novel application of lower body positive-pressure in the rehabilitation of an individual with multiple lower extremity fractures.

Objective: Lower extremity fractures, if not treated appropriately, can increase the risk of morbidity. Partial weight-bearing after surgical repair is recommended; however, current methods of partial weight-bearing may cause excessive loads through the lower extremity. A new rehabilitation tool that uses lower body positive-pressure is described, that may allow partial weight-bearing while preventing excessive loads, thereby improving functional outcomes.

Survey study of members of the Canadian Orthopaedic Association on the natural history and treatment of anterior cruciate ligament injury.

Objective: To describe current preferences and opinions of members of the Canadian Orthopaedic Association (COA) pertaining to anterior cruciate ligament (ACL) reconstruction.

Design: Survey study.

Participants: All orthopedic surgeon members of the COA residing in Canada were invited to participate.

Reliability of tunnel angle in ACL reconstruction: two-dimensional versus three-dimensional guide technique.

Purpose: To compare the reliability of tibial tunnel position and angle produced with a standard ACL guide (two-dimensional guide) or Howell 65° Guide (three-dimensional guide) in the coronal and sagittal planes. In the sagittal plane, the dependent variables were the angle of the tibial tunnel relative to the tibial plateau and the position of the tibial tunnel with respect to the most posterior aspect of the tibia. In the coronal plane, the dependent variables were the angle of the tunnel with respect to the medial joint line of the tibia and the medial and lateral placement of the tibial tunnel relative to the most medial aspect of the tibia.

Bilateral femoral neck fractures resulting from a grand mal seizure in an elderly man with Down syndrome.

Simultaneous bilateral hip fractures are exceedingly rare and usually occur following a seizure. To our knowledge, only 22 cases of such injuries have been reported in the literature during the past forty years and the majority of fractures are treated with open reduction and internal fixation. We present a case of a 66-year old man with Down syndrome and severe dementia who was diagnosed with bilateral displaced femoral neck fractures following an epileptic seizure.

Satellite cells are increasingly refractory to activation by nitric oxide and stretch in aged mouse-muscle cultures.

Age-related muscle atrophy or sarcopenia results in progressive loss of muscle function and satellite cells in aging muscle are increasingly refractory to activation that could mitigate atrophy. We know that nitric oxide release triggered by mechanical stretch of skeletal muscle, initiates satellite cell activation in vitro in single fiber, single cell and whole-muscle cultures, and in vivo in animals. This study examined muscle cell activation using tritiated-thymidine incorporation into the DNA of muscle cells in cultured muscles from female mice between 6 weeks and 18 months-of-age.