Carla L. Britton

Injury Patterns in Division I Collegiate Swimming

Background In the last 25 years, it is estimated that over 42,000 male and female swimmers have competed at the National Collegiate Athletic Association (NCAA) Division I-A level. Despite the magnitude of these numbers, little is known about the epidemiology of collegiate swimming injuries. Purpose To describe the pattern of injuries incurred for one NCAA Division I collegiate men’s and women’s swimming team over 5 seasons. Study Design Descriptive epidemiology study. Methods Musculoskeletal and head injuries reported in the Sports Injury Management System for a Division I swimming team from 2002–2007 were identified. Gender, body part, year of eligibility, position, stroke specialty, scholarship status, and team activity during which the injury occurred and lost time were recorded. Risk of injury was assessed relative to gender, stroke specialty, and year of eligibility. Results From 2002–2007, 44 male and 50 female athletes competed for the University of Iowa swimming and diving team. The overall injury rates were estimated as 4.00 injuries per 1000 exposures for men and 3.78 injuries per 1000 exposures for women. Thirty-seven percent of injuries resulted in missed time. The shoulder/upper arm was the most frequently injured body part followed by the neck/back. Freshman swimmers suffered the most injuries as well as the highest mean number of injuries per swimmer. A significant pattern of fewer injuries in later years of eligibility was also demonstrated. The relative risk (RR) for injury was higher among nonfreestyle stroke specialties (RR, 1.33 [1.00–1.77]). Injury most often occurred as a result of, or during, practice for all swimmers. However, 38% of injuries were the result of team activities outside of practice or competition, such as strength training. No significant relationship was found between occurrence of injury and gender or scholarship status. There was no significant relationship between body part injured and stroke specialty. An increased number of total injuries and an increased risk of injuries in freshman collegiate swimmers were found. Conclusion Particular attention should be given to swimmers making the transition into collegiate level swimming. These data also suggest that injury surveillance and potential prevention strategies should focus on the shoulder for in-pool activities and the axial spine for cross-training activities.

Teenage driver crash incidence and factors influencing crash injury by rurality.

BACKGROUND Previous research has identified teenage drivers as having an increased risk for motor-vehicle crash injury compared with older drivers, and rural roads as having increased crash severity compared with urban roads. Few studies have examined incidence and characteristics of teen driver-involved crashes on rural and urban roads. METHODS All crashes involving a driver aged 10 through 18 were identified from the Iowa Department of Transportation crash data from 2002 through 2008. Rates of overall crashes and fatal or severe injury crashes were calculated for urban, suburban, rural, and remote rural areas. The distribution of driver and crash characteristics were compared between rural and urban crashes. Logistic regression was used to identify driver and crash characteristics associated with increased odds of fatal or severe injury among urban and rural crashes. RESULTS For younger teen drivers (age 10 through 15), overall crash rates were higher for more rural areas, although for older teen drivers (age 16 through 18) the overall crash rates were lower for rural areas. Rural teen crashes were nearly five times more likely to lead to a fatal or severe injury crash than urban teen crashes. Rural crashes were more likely to involve single vehicles, be late at night, involve a failure to yield the right-of-way and crossing the center divider. CONCLUSIONS Intervention programs to increase safe teen driving in rural areas need to address specific risk factors associated with rural roadways. IMPACT ON INDUSTRY Teen crashes cause lost work time for teen workers as well as their parents. Industries such as safety, health care, and insurance have a vested interest in enhanced vehicle safety, and these efforts should address risks and injury differentials in urban and rural roadways.

Arthroscopic Agreement Among Surgeons on Anterior Cruciate Ligament Tunnel Placement

Background: Little is known about surgeon agreement and accuracy using arthroscopic evaluation of anterior cruciate ligament (ACL) tunnel positioning. Purpose: To investigate agreement on ACL tunnel position evaluated arthroscopically between operating surgeons and reviewing surgeons. We hypothesized that operating and evaluating surgeons would characterize tunnel positions significantly differently. Study Design: Controlled laboratory study. Methods: Twelve surgeons drilled ACL tunnels on 72 cadaveric knees using transtibial (TT), medial portal (MP), or 2-incision (TI) techniques and then completed a detailed assessment form on tunnel positioning. Then, 3 independent blinded surgeon reviewers each arthroscopically evaluated tunnel position and completed the assessment form. Statistical comparisons of tunnel position evaluation between operating and reviewing surgeons were completed. Three-dimensional (3D) computed tomography (CT) scans were performed and compared with arthroscopic assessments. Arthroscopic assessments were compared with CT tunnel location criteria. Results: Operating surgeons were significantly more likely to evaluate femoral tunnel position (92.6% vs 69.2%; P = .0054) and femoral back wall thickness as “ideal” compared with reviewing surgeons. Tunnels were judged ideal by reviewing surgeons more often when the TI technique was used compared with the MP and TT techniques. Operating surgeons were more likely to evaluate tibial tunnel position as ideal (95.5% vs 57.1%; P < .0001) and “acceptable” compared with reviewers. The ACL tunnels drilled using the TT technique were least likely to be judged as ideal on the tibia and the femur. Agreement among surgeons and observers was poor for all parameters (κ = −0.0053 to 0.2457). By 3D CT criteria, 88% of femoral tunnels and 78% of tibial tunnels were placed within applied criteria. Conclusion: Operating surgeons are more likely to judge their tunnels favorably than observers. However, independent surgeon reviewers appear to be more critical than results of 3D CT imaging measures. When subjectively evaluated arthroscopically, the TT technique yields more subjectively poorly positioned tunnels than the TI and MP techniques. Surgeons do not agree on the ideal placement for single-bundle ACL tunnels. Clinical Relevance: This study demonstrates that surgeons do not currently uniformly agree on ideal single-bundle tunnel placement and that the TT technique may yield more poorly placed tunnels.

Reliability of Tunnel Measurements and the Quadrant Method Using Fluoroscopic Radiographs After Anterior Cruciate Ligament Reconstruction

Background: Anterior cruciate ligament (ACL) reconstruction tunnel placement is often evaluated by radiographs. This study examines the interobserver reliability of various radiographic measurements of ACL tunnels. Hypothesis: When ideal radiographic views are obtained, the interobserver reliability of the measurements among experienced surgeons would be good to excellent. Study Design: Descriptive laboratory study. Methods: Tunnels for single-bundle ACL reconstruction were drilled and filled with metal interference screws or a tibial reamer on 73 cadaveric knees. Ideal fluoroscopic radiographs were obtained. Three independent reviewers performed 18 measurements including a modification of the grid method. For the grid method analysis, reviewers fit a 16 × 12 grid to the lateral knee radiograph, and the center of the femoral tunnel was marked. Interobserver reliability of the measurements was performed using intraclass correlation coefficients (ICCs). A precision grouping analysis was performed for the grid measurements to calculate the mean radius and standard deviation grouping distances. Results: The ICCs were excellent (>.75) for the tibial tunnel angles and tunnel measurements, the clock face measurement, and the Aglietti et al and Jonsson et al measurements. The ICCs were good (.4-.75) for an estimation of graft impingement, Harner et al measurements, and notch height. The mean radius for grid measurements was 0.6 ± 0.4 units (range, 0-2.36 units), with each unit being 1 box in the 16 × 12 grid. When a circle was constructed with a 1.3-unit radius, 95% of the 3 surgeons’ measurements would be included in the area of that circle. Conclusion: Reliability of ACL tunnel measurements was good to excellent under ideal circumstances for the majority of measurements. The modified grid method demonstrated very acceptable reliability. Clinical Relevance: Measurements with good to excellent reliability can be used to evaluate ACL tunnel placement when ideal radiographic views are obtained.

Agreement in the Classification and Treatment of the Superior Labrum

Background: The Snyder classification scheme is the most commonly used system for classifying superior labral injuries. Although this scheme is intended to be used for arthroscopic visual classification only, it is thought that other nonarthroscopic historical variables also influence the classification. Purpose: This study was conducted to evaluate the intrasurgeon and intersurgeon agreement in classifying variable presentations of the superior labrum and to evaluate the influence of clinical variables on the classification and treatment choices of surgeons. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A group of arthroscopic shoulder surgeons were asked to rank in order of importance clinical variables considered in diagnosing and treating the superior labrum. The surgeons then watched 50 arthroscopic videos of the superior labrum, ranging from normal to pathologic, on 3 different occasions. The first and third viewings were accompanied by no clinical information. The second viewing was accompanied by a detailed clinical vignette for each video. The surgeons selected a classification and treatment for each video. Results: A patient’s job/sport, age, and physical examination findings were considered the most important clinical variables surgeons consider during management of the superior labrum. Comparing the 2 viewings without clinical information, surgeons selected a different classification 28.5% of the time from the first to the second time. A different classification was chosen 71.5% of the time when the surgeon was supplied a clinical vignette at the subsequent viewing. Similarly, the treatment selected changed in 36% and 69.1% of cases when viewed again without vignettes and with vignettes, respectively. Intersurgeon agreement was moderate without clinical vignettes and fair with vignettes. Historical, physical examination, and surgical observations were found to influence the odds of change of classification. Conclusion: There is significant intrasurgeon and intersurgeon variability in classification and treatment of the superior labrum. Clinical historical, examination, and surgical findings influence classification and treatment choices.

Reliability of Early Postoperative Radiographic Assessment of Tunnel Placement After Anterior Cruciate Ligament Reconstruction

PURPOSE To evaluate the interobserver and intraobserver reliability of radiographic assessment of tunnel placement in anterior cruciate ligament reconstruction. METHODS Seven sports fellowship-trained orthopaedic surgeons in the Multicenter Orthopaedic Outcomes Network (MOON) group participated in the study. We prospectively enrolled 54 consecutive patients after primary anterior cruciate ligament reconstruction. Postoperative plain radiographs were obtained including a full-extension anteroposterior view of the knee, a lateral view of the knee in full extension, and a notch view at 45° of flexion (Rosenberg view). Three blinded reviewers performed 8 different radiographic measurements including those of Harner and Aglietti/Jonsson. Intraclass correlation coefficients were used to determine reliability of the measurements. Intrarater reliability was assessed by repeated measurements of a subset of 20 patient images from 1 institution, and inter-rater reliability was assessed by use of all 54 sets of films from a total of 4 institutions. RESULTS Intraobserver reliability for femoral measures ranged from none to substantial, with notch height having the worst results. Intraobserver reliability was moderate to almost perfect for tibial measures. Interobserver reliability ranged from slight to moderate for femoral measures. The Harner method for determining tunnel depth was more reliable than the Aglietti/Jonsson method. Interobserver reliability for tibial measures ranged from fair to substantial. The presence of metal interference screws did not improve reliability of measurements. CONCLUSIONS Postoperative radiographs are easily obtained, but our results show that radiographic measurements are of quite variable reliability, with most of the results falling into the fair to moderate categories.

Risk of injury by job assignment among federal wildland firefighters, United States, 2003–2007

Abstract Background: Wildland fires cost billions of dollars annually and expose thousands of firefighters to a variety of occupational hazards. Little is known about injury patterns among wildland firefighters. Methods: We examined non-fatal firefighter injuries among federal wildland firefighters reported to the US Department of the Interior for the years 2003–2007. The risk of disabling injury by job assignment, controlling for demographic and temporal variables, was assessed with logistic regression. Results: Of the 1301 non-fatal injuries, slips, trips, and falls were the most frequent injury types and sprains/strains were the most common injury. Engine crew workers suffered a third of all injuries. Handcrews and helitak/smokejumper assignments had increased odds of sprains and strains, which were the most common injury overall. Conclusions: While some injuries are equally prevalent by job assignment, others vary. Identifying hazards leading to these injuries will be essential to develop prevention strategies.

Fire characteristics associated with firefighter injury on large federal wildland fires

PURPOSE Wildland fires present many injury hazards to firefighters. We estimate injury rates and identify fire-related factors associated with injury. METHODS Data from the National Interagency Fire Center from 2003 to 2007 provided the number of injuries in which the firefighter could not return to his or her job assignment, person-days worked, and fire characteristics (year, region, season, cause, fuel type, resistance to control, and structures destroyed). We assessed fire-level risk factors of having at least one reported injury using logistic regression. Negative binomial regression was used to examine incidence rate ratios associated with fire-level risk factors. RESULTS Of 867 fires, 9.5% required the most complex management and 24.7% required the next-highest level of management. Fires most often occurred in the western United States (82.8%), during the summer (69.6%), caused by lightening (54.9%). Timber was the most frequent fuel source (40.2%). Peak incident management level, person-days of exposure, and the fires resistance to control were significantly related to the odds of a fire having at least one reported injury. However, the most complex fires had a lower injury incidence rate than less complex fires. CONCLUSIONS Although fire complexity and the number of firefighters were associated with the risk for at least one reported injury, the more experienced and specialized firefighting teams had lower injury incidence.

Anterior cruciate ligament tunnel placement.

The purpose of this cadaveric study was to analyze variation in anterior cruciate ligament (ACL) tunnel placement between surgeons and the influence of preferred surgical technique and surgeon experience level using three-dimensional (3D) computed tomography (CT). In this study, 12 surgeons drilled ACL tunnels on six cadaveric knees each. Surgeons were divided by experience level and preferred surgical technique (two-incision [TI], medial portal [MP], and transtibial [TT]). ACL tunnel aperture locations were analyzed using 3D CT scans and compared with radiographic ACL footprint criteria. The femoral tunnel location from front to back within the notch demonstrated a range of means of 16% with the TI tunnels the furthest back. A range of means of only 5% was found for femoral tunnel low to high positions by technique. The anterior to posterior tibial tunnel measure demonstrated wider variation than the medial to lateral position. The mean tibial tunnel location drilled by TT surgeons was more posterior than surgeons using the other techniques. Overall, 82% of femoral tunnels and 78% of tibial tunnels met all radiographic measurement criteria. Slight (1-7%) differences in mean tunnel placement on the femur and tibia were found between experienced and new surgeons. The location of the femoral tunnel aperture in the front to back plane relative to the notch roof and the anterior to posterior position on the tibia were the most variable measures. Surgeon experience level did not appear to significantly affect tunnel location. This study provides background information that may be beneficial when evaluating multisurgeon and multicenter collaborative ACL studies.

Surgically oriented measurements for three-dimensional characterization of tunnel placement in anterior cruciate ligament reconstruction

Objective: To develop and evaluate the feasibility and reliability of an alternative three-dimensional (3D) measurement system capable of characterizing tunnel position and orientation in ACL reconstructed knees. Methods: We developed a surgically oriented 3D measurement system for characterizing femoral and tibial drill tunnels from ACL reconstructions. This is accomplished by simulating the positioning of the drill bit originally used to create the tunnels within the bone, which allows for angular and spatial descriptions along defined axes that are established with respect to previously described anatomic landmarks and radiographic views. Computer-generated digital phantoms composed of simplified geometries were used to verify proper calculation of angular and spatial measurements. We also evaluated the inter-observer reliability of the measurements using 10 surfaces generated from cadaveric knees in which ACL tunnels were drilled. The reliability of the measurements was evaluated by intraclass correlation coefficients. Results: The digital phantom evaluation verified the measurement methods by computing angular and spatial values that matched the known values in all cases. The intraclass correlation coefficient was calculated for four users and was found to range from 0.95 to 0.99 for the femoral and tibial measurements, demonstrating near-perfect agreement. Conclusions: The characterization of ACL tunnels has historically concentrated on two-dimensional (2D) measurements; however, it can be difficult to define ACL tunnel placement using 2D methods. We have presented novel techniques for defining graft tunnel placement from 3D surface representations of the ACL reconstructed knee. These measurements provide exact tunnel location spatially and along axes that offer the potential to comparatively analyze ACL reconstructions post-operatively using advanced imaging. These methods are reliable, and have been demonstrated to be applicable to multiple single-bundle techniques for ACL reconstruction.