Context:Stress fractures are common injuries in athletes, often difficult to diagnose. A stress fracture is a fatigue-induced fracture of bone caused by repeated applications of stress over time.Evidence Acquisition:PubMed articles published from 1974 to January 2012.Results:Intrinsic and extrinsic factors may predict the risk of stress fractures in athletes, including bone health, training, nutrition, and biomechanical factors. Based on their location, stress fractures may be categorized as low- or high-risk, depending on the likelihood of the injury developing into a complete fracture. Treatment for these injuries varies substantially and must account for the risk level of the fractured bone, the stage of fracture development, and the needs of the patient. High-risk fractures include the anterior tibia, lateral femoral neck, patella, medial malleolus, and femoral head. Low-risk fractures include the posteromedial tibia, fibula, medial femoral shaft, and pelvis. Magnetic resonance is the imaging test of choice for diagnosis.Conclusions:These injuries can lead to substantial lost time from participation. Treatment will vary by fracture location, but most stress fractures will heal with rest and modified weightbearing. Some may require more aggressive intervention, such as prolonged nonweightbearing movement or surgery. Contributing factors should also be addressed prior to return to sports.

Ergogenic drugs are substances that are used to enhance athletic performance. These drugs include illicit substances as well as compounds that are marketed as nutritional supplements. Many such drugs have been used widely by professional and elite athletes for several decades. However, in recent years, research indicates that younger athletes are increasingly experimenting with these drugs to improve both appearance and athletic abilities. Ergogenic drugs that are commonly used by youths today include anabolic-androgenic steroids, steroid precursors (androstenedione and dehydroepiandrosterone), growth hormone, creatine, and ephedra alkaloids. Reviewing the literature to date, it is clear that children are exposed to these substances at younger ages than in years past, with use starting as early as middle school. Anabolic steroids and creatine do offer potential gains in body mass and strength but risk adverse effects to multiple organ systems. Steroid precursors, growth hormone, and ephedra alkaloids have not been proven to enhance any athletic measures, whereas they do impart many risks to their users. To combat this drug abuse, there have been recent changes in the legal status of several substances, changes in the rules of youth athletics including drug testing of high school students, and educational initiatives designed for the young athlete. This article summarizes the current literature regarding these ergogenic substances and details their use, effects, risks, and legal standing.www.pediatrics.org/cgi

Background The initial graft tension applied at the time of anterior cruciate ligament (ACL) reconstruction alters joint contact and may influence cartilage health. The objective was to compare outcomes between two commonly used “laxity-based” initial graft tension protocols. Hypothesis We hypothesized that; 1) the high-tension group would have less knee laxity, improved clinical and patient-oriented outcomes, and less cartilage damage than the low-tension group after 36-months of healing, and 2) the outcomes of the high-tension group would be equivalent to those of a matched control group. Study Design Randomized controlled clinical trial. Methods Ninety patients with isolated unilateral ACL injuries were randomized to undergo ACL reconstruction using one of two initial graft tension protocols; 1) autografts tensioned to restore normal anteroposterior (AP) laxity at the time of surgery (i.e., “low-tension”; n=46) and 2) autografts tensioned to over-constrain AP laxity by 2 mm (i.e., “high-tension”; n=44). Sixty matched healthy subjects formed the control group. Outcomes were assessed pre-operatively, intra-operatively, and at 6-, 12- and 36-months after surgery. Results No significant differences were found between the two initial graft tension protocols for any of the outcome measures at 36-months. However, there were differences when comparing the two treatment groups to the control group. On average, AP laxity was 2 mm greater in the ACL reconstructed groups than in the control group (p<.007). IKDC knee evaluation scores (p<0.001), peak isokinetic knee extension torques (p<.027), and 4 out of 5 of the Knee Osteoarthritis Outcome Scores (KOOS; p<.05) were significantly worse than the control group. SF-36 scores and re-injury rates were similar between groups at 36-months. Although there were significant radiographic and MRI changes present in the ACL reconstructed knees of both treatment groups, the magnitude was relatively small and likely clinically insignificant at 36-months. Conclusions Both laxity-based initial graft tension protocols produced similar outcomes without fully restoring joint function and KOOS scores when compared to the control group. There was minimal evidence of cartilage damage 36-months after surgery.

To investigate primary and secondary signs of anterior cruciate ligament (ACL) tear at magnetic resonance (MR) imaging, the authors retrospectively reviewed 103 MR imaging examinations obtained in 99 patients, the original interpretations of these examinations, clinical records, and arthroscopy reports. Fifty cases of arthroscopy-documented complete ACL tear were included. The primary signs of ACL tear (ie, abnormal ACL morphologic features or signal intensity) had respective sensitivity and specificity values of 96% (48 of 50 examinations) and 94% (50 of 53) on sagittal images and 92% (46 of 50) and 83% (43 of 52) on coronal images. As a secondary sign of ACL tear, bone bruise involving the lateral compartment of the knee was found in 40% (20 of 50) of cases of ACL tear and in 4% (2 of 53) of cases of normal ACL. The mean curvature of the posterior cruciate ligament was increased (0.40 vs 0.27; P < .0001) in cases of ACL tear. An abnormal appearance of the ACL on sagittal images remains the single most sensitive and specific sign of ACL tear.

Background Clinical, functional and patient-oriented outcomes are commonly used to evaluate the efficacy of treatments following ACL injury; however, these evaluation techniques do not directly measure the biomechanical changes that occur with healing. Purpose To determine if the magnetic resonance (MR) image-derived parameters of graft volume and signal intensity (SI), which have been used to predict the biomechanical (i.e., structural properties) of the graft in animal models, correlate with commonly used clinical (anteroposterior (AP) knee laxity), functional (1-leg hop) and patient-oriented outcome measures (KOOS) in patients 3- and 5-years after ACL reconstruction. Study Design Descriptive Laboratory Study Methods Using a subset of participants enrolled in an ongoing ACL reconstruction clinical trial, AP knee laxity, 1-legged hop test, and KOOS were assessed at 3- and 5-year follow-up. 3-D T1-weighted MR images were collected at each visit. Both the volume and median SI of the healing graft were determined and used as predictors in a multiple regression linear model to predict the traditional outcome measures. Results Graft volume combined with median SI in a multiple linear regression model predicted 1-legged hop test at both the 3-year and 5-year follow-up visits (R2=.40, p=.008 and R2=.62, p=.003, respectively). Similar results were found with 5-year follow up for the KOOS quality of life (R2=.49, p=.012), sport_function (R2=.37, p=.048), pain (R2=.46, p=.017) and symptoms (R2=.45, p=.021) sub-scores, though these variables were not significant at 3 years. The multiple linear regression model for AP knee laxity at 5-year follow-up approached significance (R2=.36, p=.088). Conclusion The MR parameters (volume and median SI) used to predict ex vivo biomechanical properties of the graft in an animal model have the ability to predict clinical or in vivo outcome measures in patients at 3- and 5-year follow-up.

Background The “initial graft tension” applied at the time of graft fixation during ACL reconstruction surgery modulates joint contact mechanics, which in turn may promote post-traumatic osteoarthritis (OA). The objectives of this prospective randomized controlled trial were to compare clinical, functional, patient reported, and OA imaging outcomes between two different initial laxity-based graft tension cohorts and a matched uninjured control group, and to evaluate the effects of laxity-based graft tension on OA development at 84 months follow-up. The two laxity-based tension protocols were: 1) to restore normal anteroposterior (AP) laxity at the time of surgery relative to the contralateral uninjured knee (“low-tension” group), or 2) to over-constrain AP laxity by 2mm relative to the contralateral uninjured knee (“high-tension” group). Hypothesis We hypothesized that 1) the high-tension group would have improved outcomes and decreased OA compared to the low-tension group after 84-months, and 2) the outcomes for the high-tension group would be equivalent to an age, sex-, race-, and activity matched group of control subjects with normal knees. Study Design Randomized Controlled Trial (Level 1) Methods Patients were reconstructed either with a bone-patellar tendon-bone or a four-stranded hamstring autograft, and outcomes were compared to a matched control group recruited from the local area via advertising. Clinical, functional, patient reported and OA imaging outcomes were evaluated pre-operatively and at 60 and 84 months post-op. Repeated measures ANOVA were used to evaluate differences in outcomes between treatment groups and the control group. Results There were significant differences between the two tension groups in one of five KOOS outcomes (Sport, P=.04), and two of eight SF-36 scores (vitality and mental health, P<.04) at 84 and 60 months, respectively. Both tension groups scored significantly worse than the control group in IKDC exam (P<.001), 1-hop distance (P<=.017), KOOS Quality of Life and Symptoms (P<.03), and OARSI radiographic score (P<=.02) at 84 months. The low-tension group did worse than the control group in KOOS Pain (P=.03), SF-36 General Health and Social Functioning (P<.04), and the Whole-Organ MRI Score (P=.001), while the high-tension group was different than the control group in knee laxity (P<.001), radiographic joint space width (P=.003), OARSI score (P=.003), and had significantly more subsequent knee injuries (P=.02) at 84 months. Conclusion The results do not support our hypotheses that the high-tension group would have improved outcomes when compared to the low-tension group after 84 months of healing, and that the outcomes for the high-tension group would be equivalent to the matched control group. While there were minor differences in patient reported outcomes between the two laxity-based tension groups, all other outcomes were similar.

Improvement in the accessibility and quality of information on orthopaedic sports medicine fellowship web sites would facilitate the ability of applicants to obtain useful information.

Catastrophic cervical spine injuries can lead to devastating consequences for the collision athlete. Improved understanding of these injuries can facilitate early diagnosis and effective on-field management. This article is the first of a 2-part series. The first part reviews the current concepts regarding the epidemiology, functional anatomy, and diagnostic considerations relevant to cervical spine trauma in collision sports. In the second part, to be published later, the principles of emergency care of the cervical spine-injured athlete are reviewed. This article provides a rational approach to the early recognition of the different clinical syndromes associated with catastrophic cervical spine injury. Rapid on-field diagnosis can help to optimize the outcomes of these catastrophic injuries.