Risk Factors for Concussion in Under 18, Under 22 and Professional Men's Rugby Union: A Video Analysis of 14,809 Tackles.

OBJECTIVE: This study aimed to identify the risk factors for tackle-related concussion observed in matches involving under (U) 18, U 22 and professional men's Rugby Union players through video analysis. STUDY DESIGN: Descriptive epidemiology study. METHODS: Twenty Rugby Union matches each for high school (U18), university/college (U22) and professional (Elite) were randomly selected from 202 matches in the 2018/2019 season. Both one-on-one and tackles involving multiple tacklers were analyzed for the 60 matches. The 28 categorical and continuous variables (e.g., tackle characteristics and duration before the tackle) were applied as risk factors to a least absolute shrinkage and selection operator (Lasso) regression analysis. To identify high-risk situations, a simulation model with coefficients obtained from the Lasso regression was used. Statistical analysis was conducted according to tackle direction. RESULTS: A total of 14,809 tackles and 41 concussions involving 1800 players were included in the analyses. The incidence rate of concussions (injuries/1000 tackles) was greater in Elite players (4.0) compared with U18 (1.9) and U22 (2.4) players. The factors most highly associated with concussions were head-in-front tackles (where the tackler's head is placed forward, impeding a ball carrier's forward movements, 11.26/1000 tackles), and were more often observed among U18 players. A simulation model predicted that the highest risk tackle situation in Elite players was a head-in-front, side-on tackle below the hip of the ball carrier (predicted incidence rate 18.07/1000 tackles). CONCLUSION: The risk factors associated with concussion need to be assessed cautiously. Avoiding head-in-front, side-on tackles to the lower extremities of a ball carrier should be considered to reduce injury risks.

Glenoid Bone Loss Is a Risk Factor for Poor Clinical Results After Coracoid Transfer in Rugby Players With Shoulder Dislocations.

BACKGROUND: Although surgical shoulder stabilization via coracoid transfer in collision athletes is effective and has a low reinjury rate, the factors affecting poor clinical results and the superiority of the 2 stabilization procedures (Bristow and Latarjet) remain unclear. PURPOSE: To explore the factor(s) affecting poor clinical results of coracoid transfer in a large cohort of rugby players and to compare postoperative function between the Bristow and Latarjet procedures. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study included 169 consecutive shoulders of 154 competitive male rugby players who underwent shoulder stabilization surgery (Bankart repair with coracoid transfer) between 2014 and 2018 and had a mean follow-up of 2.7 years (minimum follow-up, 2 years). The Bristow procedure was performed in the first 92 shoulders (84 players), and the Latarjet procedure was performed in the latter 77 shoulders (70 players). A poor clinical result was defined as a postoperative Rowe score of <70 and a postoperative Western Ontario Shoulder Instability Index (WOSI) score of >630. Multiple logistic regression analysis was conducted to identify the factors affecting postoperative functional failure. The postoperative scores and complication rates were also compared between the 2 procedures. RESULTS: In total, 92.3% of the rugby players returned to their preinjury competition level at a mean of 5.9 months postoperatively. The Rowe and WOSI scores showed that shoulder function was improved postoperatively compared with preoperatively. The number of rugby players with a poor clinical result was 18 (10.7%). Multiple logistic regression analysis demonstrated that a poor clinical result was associated with a preoperative glenoid bone defect of >20% of the glenoid width (odds ratio, 9.8), whereas the clinical result was unaffected by the type of coracoid transfer. There were no differences between the 2 procedures in any of the postoperative scores or complication rates. CONCLUSION: The present study indicated that the most effective predictor of postoperative functional scores was the degree of the glenoid bone defect and not the type of coracoid transfer. This information may be useful for the strategic treatment of shoulder dislocations in collision athletes.

The Number of Injury Events Associated With the Critical Size of Bipolar Bone Defects in Rugby Players With Traumatic Anterior Shoulder Instability.

BACKGROUND: The size of a glenoid bone defect is responsible for reduction in shoulder stability and is correlated with the number of instability events. Biomechanical studies have suggested that it should be considered concomitantly with the Hill-Sachs lesion as "bipolar" bone defects for assessing structural degradation, but the definitive number of instability events associated with the critical size has not been investigated. PURPOSE: To (1) confirm that the number of instability events is the predictor of a critical size of bipolar bone defects and (2) demonstrate the cutoff value of the number of instability events for these defects in rugby players with traumatic anterior shoulder instability. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: One-hundred forty-four rugby players with anterior shoulder instability underwent morphologic evaluation for glenoid and Hill-Sachs lesions by computed tomography and determination of the critical (a glenoid bone defect of ≥25% or an off-track Hill-Sachs lesion) and subcritical (a glenoid bone defect of ≥13.5%) size of bipolar bone defects. In the primary analysis, the prevalence of the critical and subcritical size of bipolar bone defects was investigated. In the secondary analysis, the authors explored the predictors for these bone defects and determined the cutoff value correlating with the critical and subcritical size of bipolar bone defects by applying receiver operating characteristic curves. RESULTS: The primary analysis revealed that the prevalence of critical and subcritical size of bipolar bone defects was 20.8% and 61.8% of 144 shoulders, respectively. In the secondary analysis, multiple logistic regression analysis demonstrated that the total number of shoulder instability events and dominant shoulder were the significant factors associated with the critical and subcritical size of bipolar bone defects. The cutoff value for the number of instability events that correlated with critical bipolar bone defects was 6 for the dominant and 9 for the nondominant shoulder, whereas it was 4 for the dominant and 5 for the nondominant shoulder for subcritical bipolar bone defects. CONCLUSION: The number of shoulder instability events and the dominant shoulder were the predictors for the critical and subcritical size of bipolar bone defects for a shoulder with traumatic instability. Four injury events should herald caution when treating rugby players with shoulder instability.

Tackler's head position relative to the ball carrier is highly correlated with head and neck injuries in rugby.

OBJECTIVES: To characterise the tackler's head position during one-on-one tackling in rugby and to determine the incidence of head, neck and shoulder injuries through analysis of game videos, injury records and a questionnaire completed by the tacklers themselves. METHODS: We randomly selected 28 game videos featuring two university teams in competitions held in 2015 and 2016. Tackles were categorised according to tackler's head position. The 'pre-contact phase' was defined; its duration and the number of steps taken by the ball carrier prior to a tackle were evaluated. RESULTS: In total, 3970 tackles, including 317 (8.0%) with the tackler's head incorrectly positioned (ie, in front of the ball carrier) were examined. Thirty-two head, neck or shoulder injuries occurred for an injury incidence of 0.8% (32/3970). The incidence of injury in tackles with incorrect head positioning was 69.4/1000 tackles; the injury incidence with correct head positioning (ie, behind or to one side of the ball carrier) was 2.7/1000 tackles. Concussions, neck injuries, 'stingers' and nasal fractures occurred significantly more often during tackles with incorrect head positioning than during tackles with correct head positioning. Significantly fewer steps were taken before tackles with incorrect head positioning that resulted in injury than before tackles that did not result in injury. CONCLUSION: Tackling with incorrect head position relative to the ball carrier resulted in a significantly higher incidence of concussions, neck injuries, stingers and nasal fractures than tackling with correct head position. Tackles with shorter duration and distance before contact resulted in more injuries.

Midterm Clinical Results in Rugby Players Treated With the Bristow Procedure.

BACKGROUND: Although surgical shoulder stabilization by coracoid transfer is effective for collision athletes and has a low reinjury rate, no reports have described the midterm results of this procedure in specific patient cohorts of sufficient number or provided subjective assessments of these patients. PURPOSE: To evaluate midterm results after treatment of shoulder instability with the Bristow procedure in a large cohort of rugby players. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This study included 176 shoulders of 152 competitive rugby players who underwent shoulder stabilization surgery (Bristow procedure with Bankart repair) with a mean follow-up of 4 years (minimum of 2 years) in our institute. The primary outcome measure was the difference in the presurgical and postsurgical functional Rowe score and Western Ontario Shoulder Instability index (WOSI) score and factors affecting these scores. Complication rates and associated factors were also investigated. RESULTS: In total, 176 shoulders of 152 patients underwent the Bristow procedure with Bankart repair, and 93.2% of the players returned to their preinjury competition level at a mean of 6.3 months postoperatively. All Rowe and WOSI scores were significantly improved after surgery. The numbers of shoulders with functional failure as indicated by the Rowe score, WOSI score, and inability to return to the previous level of play were 28 (15.9%), 54 (30.7%), and 12 (6.8%), respectively. Multiple logistic regression analyses demonstrated that reinjury after surgery (odds ratio [OR] = 35.1) and the number of shoulder dislocations (OR = 11.2-11.4) negatively affected the competition level after return to play, while reinjury (OR = 11.1-17.8), the number of shoulder subluxations (OR = 1.1-2.9), injury in the dominant shoulder (OR = 1.2-2.2), and large bone defects (OR = 1.1-11.5) negatively affected functional scores. Reinjury after shoulder stabilization occurred in 6 of 176 shoulders (3.4%). Multiple logistic regression analysis demonstrated that reinjury after surgery occurred more frequently in players at lower versus higher grade levels of competition (OR = 21.0). Although differences were not significant, a trend was noted toward higher postoperative reinjury rates in forward players, those in the upper categories (professional and college), and those with injury in the nondominant shoulder. CONCLUSION: The Bristow procedure provides good midterm outcomes for competitive collision athletes, while postsurgical reinjury, the number of preoperative dislocations and subluxations, and large bone defects negatively affect postsurgical shoulder function. This information may be useful for treatment of shoulder dislocations in collision athletes.