Time to return to play after high ankle sprains in collegiate football players: a prediction model.

BACKGROUND: Determining the severity of high ankle sprains in athletes and predicting the time that an athlete can return to unrestricted sport activities following this injury remain significant challenges. PURPOSE: The objectives of this study were (1) to determine if objective measurements of injury severity after high ankle sprains could predict the time to return to play in Division I football players and (2) to determine whether physical examination or diagnostic musculoskeletal ultrasound was more predictive of return to play. The hypothesis was that objective measures of injury severity of a high ankle sprain can be predictive of time to return to athletic participation in collegiate football players. STUDY DESIGN: Prospective case series. METHODS: Twenty consecutive Division I collegiate football players with a diagnosis of a grade I high ankle sprain (syndesmosis sprain without diastasis) were studied. Two clinical measurements of injury severity were determined: the height of the zone of injury on physical examination and the height of the zone of injury as defined by diagnostic musculoskeletal ultrasound examination. All athletes followed a standardized treatment program and return-to-play criteria. A regression model and Cox proportional hazards model were developed to determine time to return to unrestricted play as a function of injury severity and player position. RESULTS: Physical examination but not ultrasound was significantly correlated with time to return to play. Regression and Cox analyses revealed that injury severity on physical examination and player position were significant predictors of time to return to unrestricted play following high ankle sprain. CONCLUSIONS: Injury severity on physical examination and player position are associated with the time to return to unrestricted athletic activity after injury. A model based on the data can be applied to help predict the time to return to unrestricted play in Division I collegiate football players following high ankle sprain.

Bone density of the greater tuberosity is decreased in rotator cuff disease with and without full-thickness tears.

BACKGROUND: Despite the high prevalence of rotator cuff disease in the aging adult population, the basic mechanisms initiating the disease are not known. It is known that changes occur at both the bone and tendon after rotator cuff tears. However, no study has focused on early or "pretear" rotator cuff disease states. The purpose of this study was to compare the bone mineral density of the greater tuberosity in normal subjects with that in subjects with impingement syndrome and full-thickness rotator cuff tears. MATERIALS AND METHODS: Digital anteroposterior shoulder radiographs were obtained for 3 sex- and age-matched study groups (men, 40-70 years old): normal asymptomatic shoulders (control), rotator cuff disease without full-thickness tears (impingement), and full-thickness rotator cuff tears (n = 39 per group). By use of imaging software, bone mineral densities were determined for the greater tuberosity, the greater tuberosity cortex, the greater tuberosity subcortex, and the cancellous region of the humeral head. RESULTS: The bone mineral density of the greater tuberosity was significantly higher for the normal control subjects compared with subjects with impingement or rotator cuff tears. No differences were found between the two groups of patients with known rotator cuff disease. The greater tuberosity cortex and greater tuberosity subcortex outcome measures were similar. CONCLUSION: Bone mineral changes are present in the greater tuberosity of shoulders with rotator cuff disease both with and without full-thickness tears. The finding of focal diminished bone mineral density of the greater tuberosity in the absence of rotator cuff tears warrants further investigation.

Lung cells from neonates show a mesenchymal stem cell phenotype.

RATIONALE: Mesenchymal stem cells have been isolated from adult bone marrow, peripheral blood, adipose tissue, trabecular bone, articular synovium, and bronchial submucosa. OBJECTIVES: We hypothesized that the lungs of premature infants undergoing mechanical ventilation contain fibroblast-like cells with features of mesenchymal stem cells. METHODS: Tracheal aspirate fluid from mechanically ventilated, premature (< 30 wk gestation) infants 7 days old or younger was obtained from routine suctioning and plated on plastic culture dishes. MEASUREMENTS AND MAIN RESULTS: A total of 11 of 20 patients studied demonstrated fibroblast-like cells, which were identified as early as 6 hours after plating. Cells were found to express the mesenchymal stem cell markers STRO-1, CD73, CD90, CD105, and CD166, as well as CCR2b, CD13, prolyl 4-hydroxylase, and alpha-smooth muscle actin. Cells were negative for the hematopoietic and endothelial cell markers CD11b, CD31, CD34, or CD45. Tracheal aspirate monocyte chemoattractant protein-1/CCL2 levels were ninefold higher in aspirates in which fibroblast-like cells were found, and cells demonstrated chemotaxis in response to monocyte chemoattractant protein. Placement of cells into appropriate media resulted in adipogenic, osteogenic, and myofibroblastic differentiation. Patients from whom mesenchymal stem cells were isolated tended to require more days of mechanical ventilation and supplemental oxygen. CONCLUSIONS: Together, these data demonstrate that tracheal aspirate fluid from premature, mechanically ventilated infants contains fibroblasts with cell markers and differentiation potential typically found in mesenchymal stem cells.