Amanda O. Esquivel

Concussion Management, Education, and Return-to-Play Policies in High Schools: A Survey of Athletic Directors, Athletic Trainers, and Coaches

Background: Concussions represent 8.9% to 13.2% of all high school athletic injuries. How these injuries are managed is currently unknown. Hypothesis: There are differences in concussion management and awareness among boys football, boys ice hockey, and boys and girls soccer. Study Design: Descriptive epidemiologic study. Methods: High school athletic directors were contacted via e-mail and asked to complete, and request that their staff complete, an online survey with 4 sections aimed at athletic directors, head coaches, team physicians, and certified athletic trainers. Results: According to coaches, concussion awareness education was provided for football (97%), hockey (65%), and boys and girls soccer (57% and 47%, respectively) (P < 0.01). Use of sideline screening tools was significantly greater for football (P = 0.03). All participants agreed that a player who has suffered a concussion cannot return to play the same day. Conclusion: There is a difference in concussion management and awareness among the 4 sports. Concussion education is well promoted in football but should be expanded in soccer and hockey. Players are not allowed to return to play the same day, and the majority are referred to a physician. Clinical Relevance: Study results highlight the differences in concussion education among sports. Health care providers should address these gaps.

A novel strontium-doped calcium polyphosphate/erythromycin/poly(vinyl alcohol) composite for bone tissue engineering.

It is our goal to develop bactericidal bone scaffolds with osteointegration potential. In this study, poly(vinyl alcohol) (PVA) coating (7%) was applied to an erythromycin (EM)-impregnated strontium-doped calcium polyphosphate (SCPP) scaffold using a simple slurry dipping method. MicroCT analysis showed that PVA coating reduced the average pore size and the percentage of pore interconnectivity to some extent. Compressive strength tests confirmed that the PVA coating significantly increased material elasticity and slightly enhanced the scaffold mechanical strength. It was also confirmed that the PVA coatings allowed a sustained EM release that is controlled by diffusion through the intact PVA hydrogel layer, irrespective of the drug solubility. PVA coating did not inhibit the EM bioactivity when the scaffolds were immersed in simulated body fluid for up to 4 weeks. EM released from SCPP-EM-PVA composite scaffolds maintained its capability of bacterial growth (S. aureus) inhibition. PVA coating is biocompatible and nontoxic to MC3T3 preosteoblast cells. Furthermore, we found that SCPP-EM-PVA composite scaffolds and their eluants remarkably inhibited RANKL-induced osteoclastogenesis in a murine RAW 264.7 macrophage cell line. Thus, this unique multifunctional bioactive composite scaffold has the potential to provide controlled delivery of relevant drugs for bone tissue engineering.

Soccer-Related Injuries in Children and Adults Aged 5 to 49 Years in US Emergency Departments From 2000 to 2012

Background: An increase in soccer-related injuries occurred in the United States between 2000 and 2012; however, most studies of soccer-related injuries have only examined the pediatric population and not adults. Hypothesis: The number of soccer injuries is increasing in both the pediatric and adult populations. There are differences in injury types and counts when comparing male and female players within various age groups. Study Design: Descriptive epidemiology study. Level of Evidence: Level 4. Methods: This retrospective analysis surveyed the US Consumer Product Safety Commission’s National Electronic Injury Surveillance System (NEISS) database from 2000 to 2012 for soccer-related injuries in children and adults aged 5 to 49 years. Results: From 2000 to 2012, there were an estimated 2,472,066 soccer-related injuries among 5- to 49-year-olds; 629,994 (25.5%) in adults (aged 20-49 years). The overall estimated pediatric injury count increased significantly over the time period (R2 = 0.764, P < 0.001). In the 20- to 49-year age range, there was also a significant increase in the estimated number of injuries over the 13-year period, from 41,292 injuries in 2000 to 55,743 in 2012 (R2 = 0.719, P < 0.001). The estimated injury counts for male players were significantly higher than female players in any given year for all age groups (P < 0.001). Girls aged 5 to 19 years were more likely to have lower extremity injuries than boys (odds ratio [OR], 1.256; 95% CI, 1.214-1.299; P < 0.001). The most common injuries reported were strain/sprains (33.3%), fractures (23.7%), and contusions and abrasions (17.4%) within the 5- to 49-year age category. In both sexes, strains and sprains were significantly lower among 5- to 19-year-olds in comparison with 20- to 49-year-olds (OR, 0.740; 95% CI, 0.714-0.766; P < 0.001). Conclusion: There are age- and sex-related differences in estimated injury count, body part injured, type of injury, and hospital admissions for soccer. Also, estimated injury count increased over the 2000 to 2012 time period. Clinical Relevance: This study demonstrates that there are differences between pediatric and adult injuries, based on sex, body part, type of injury, and hospital admissions.

Load to Failure and Stiffness: Anchor Placement and Suture Pattern Effects on Load to Failure in Rotator Cuff Repairs.

Background: Rotator cuff tendinopathy is a frequent cause of shoulder pain that can lead to decreased strength and range of motion. Failures after using the single-row technique of rotator cuff repair have led to the development of the double-row technique, which is said to allow for more anatomical restoration of the footprint. Purpose: To compare 5 different types of suture patterns while maintaining equality in number of anchors. The hypothesis was that the Mason-Allen–crossed cruciform transosseous-equivalent technique is superior to other suture configurations while maintaining equality in suture limbs and anchors. Study Design: Controlled laboratory study. Methods: A total of 25 fresh-frozen cadaveric shoulders were randomized into 5 suture configuration groups: single-row repair with simple stitch technique; single-row repair with modified Mason-Allen technique; double-row Mason-Allen technique; double-row cross-bridge technique; and double-row suture bridge technique. Load and displacement were recorded at 100 Hz until failure. Stiffness and bone mineral density were also measured. Results: There was no significant difference in peak load at failure, stiffness, maximum displacement at failure, or mean bone mineral density among the 5 suture configuration groups (P < .05). Conclusion: According to study results, when choosing a repair technique, other factors such as number of sutures in the repair should be considered to judge the strength of the repair. Clinical Relevance: Previous in vitro studies have shown the double-row rotator cuff repair to be superior to the single-row repair; however, clinical research does not necessarily support this. This study found no difference when comparing 5 different repair methods, supporting research that suggests the number of sutures and not the pattern can affect biomechanical properties.

Effect of erythromycin-doped calcium polyphosphate scaffold composite in a mouse pouch infection model

We previously showed that strontium-doped calcium polyphosphate (SCPP) scaffold with poly(vinyl alcohol) (PVA) coating extended the impregnated erythromycin (EM) release. In this study, we examined the bactericidal effect of EM-doped SCPP (SCPP(EM) ) scaffolds with PVA coating in a Staphylococcus aureus (S. aureus) infected mouse pouch. SCPP scaffolds with or without 5% EM, and SCPP(EM) scaffolds coated with PVA (with or without 5% EM) were prepared. Scaffolds were implanted in the pouch of BALB/c mice, followed by inoculation of 1 × 10(3) colony-forming units of S. aureus. Mice were sacrificed 14 days after surgery. Pouch tissues and scaffolds were collected for histology, scanning electron microscopy, and microbiological analysis. In the absence of SCPP scaffolds, the pouch infection was eliminated by the host immune surveillance. In the presence of SCPP scaffolds, both the pouch tissues and scaffolds were infected, but SCPP(EM) scaffolds successfully inhibited bacterial growth. Although PVA coating of SCPP(EM) scaffolds enhanced bacterial growth, incorporation of EM into PVA coating inhibited growth. In conclusion, BALB/c mice were capable of eradicating a low grade S. aureus infection. SCPP protected S. aureus growth from host immune surveillance. Though PVA coating sustained EM release in vitro, it was unable to inhibit bacterial growth because PVA gel matrix provided a temporary shelter for bacteria to grow and slowed the EM release from SCPP scaffold. To guarantee a sufficient inhibition of bacterial growth at the initial stage, embedding EM or other antibiotics in the PVA coating is also essential.

The Biomechanical Stability of Distal Clavicle Excision Versus Symmetric Acromioclavicular Joint Resection

Background: Treatment for acromioclavicular (AC) joint pain may include distal clavicle excision (DCE). It is possible that DCE can disrupt the surrounding ligaments, leading to increased AC joint laxity. Purpose: To determine the load to failure and stiffness of the AC joint after DCE and symmetric acromioclavicular joint resection (ACJR). Study Design: Controlled laboratory study. Methods: Specimens were randomly assigned to 1 of 2 groups: 1-cm DCE (n = 10) or symmetric (5-mm excision of acromion and distal clavicle) ACJR (n = 10). The specimens were loaded intact in the anterior-posterior plane to determine anteroposterior translation. This was repeated after surgery and compared. The specimens were loaded at 2 mm/s until clinical failure. Force and displacement were recorded, and stiffness was calculated. Results: The peak load to failure for the DCE group was 387.8 N (standard error of the mean [SEM], 31.4 N) and for the ACJR group was 468.5 N (SEM, 30.9 N) (P = .035). The average stiffness for the DCE group was 35.2 N/mm (SEM, 2.5 N/mm) and for the ACJR group was 37.4 N/mm (SEM, 2.3 N/mm) (P = .11). There was no significant difference in the anteroposterior translation before and after resection for either group (P > .05). Conclusion: This cadaveric study demonstrates that the anterior-posterior load to clinical failure of the AC joint after 5 mm of resection from the distal clavicle and medial acromion is significantly greater than 1 cm of the resected distal clavicle alone. Clinical Relevance: Performing ACJR may improve joint stability, leading to fewer complications when compared with DCE.

Comparison of ACL Strain in the MCL-Deficient and MCL-Reconstructed Knee During Simulated Landing in a Cadaveric Model:

Background: Noncontact anterior cruciate ligament (ACL) injury after valgus landing has been reported and studied biomechanically. However, the role of the medial collateral ligament (MCL) in dissipating these forces has not been fully elucidated. Purpose/Hypothesis: The purpose of this study was to investigate the role that the MCL plays in ACL strain during simulated landing. The hypothesis was that ACL strain would increase significantly in MCL-incompetent knees compared with the native knee and that reconstructing the MCL would return the values to those of the intact knee. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen human cadaveric knees were used in this study. A materials testing machine applied a force of 2× body weight over 60 milliseconds to simulate landing after a jump. The knees were tested in 12 loading conditions, consisting of full extension or 15° of flexion combined with 7° of valgus or neutral alignment while the tibia was in external rotation, neutral rotation, or internal rotation. This test procedure was repeated on each specimen with the MCL transected and reconstructed. The superficial and deep MCL was transected along with the posterior oblique ligament, which was thought to simulate a worst case scenario. The MCL was reconstructed by use of semitendinosus and gracilis tendon grafts. Results: During internal rotation at 0° of flexion and 0° of valgus, both the intact (P = .005) and the reconstructed (P = .004) MCL states placed significantly lower strain on the ACL than did the transected MCL. The reconstructed MCL state at 0° of flexion and 7° of valgus (P = .049) along with 15° of flexion and 0° of valgus (P = .020) also placed significantly lower strain on the ACL than did the transected MCL. For external rotation testing at 0° of flexion and 7° of valgus, the reconstructed MCL state placed significantly lower strain on the ACL than did the transected MCL (P = .039). Finally, during neutral rotation, the ACL strain at 0° of valgus and 0° of flexion, and at 7° of valgus and 0° of flexion was significantly lower for the MCL-intact groups (P < .028) and MCL-reconstructed groups (P < .016) than the MCL-transected groups. Conclusion: The current findings demonstrate that during valgus landing, a knee with an incompetent MCL puts the ACL under increased strain. These values are highest in full extension with the tibia in internal and neutral rotation. This increased strain can be reduced to baseline levels with reconstruction. Clinical Relevance: A knee with an incompetent MCL puts the ACL under increased strain. Once the MCL has healed in an elongated manner, MCL reconstruction should be considered.

Temperature Change When Drilling Near the Distal Femoral Physis in a Skeletally Immature Ovine Model.

Background: The possibility of physeal injury during anterior cruciate ligament reconstruction in the pediatric population is a concern. The purpose of this study was to determine whether drilling at or near the physis could cause a temperature increase that could trigger chondrolysis. Methods: Skeletally immature cadaveric lamb distal femurs were used for this study and randomly placed in 1 of 6 groups (n=10 in each group). We examined the 8 and 10 mm Flipcutter at a distance of 0.5 mm from the physis and an 8 and 10 mm acorn-tipped reamer at a distance of 0.5 and 3.0 mm from the physis. During drilling, temperature change at the distal femoral physis was continuously measured until the temperature decreased to the original value. Results: An interreamer comparison yielded a significant difference when drilling 0.5 mm from the physis (P=0.001). Pair-wise Mann-Whitney post hoc tests were performed to further evaluate the differences among the groups. The 8 mm FlipCutter had a significantly higher maximum temperature (39.8±1.4°C) compared with the 10 mm FlipCutter (38.0±0.6°C, P=0.001), 8 mm acorn-tipped reamer (38.1±0.9°C, P=0.007), and 10 mm acorn-tipped reamer (37.5±0.3°C, P<0.001). Conclusions: The risk of thermal-induced injury to the physis is low with an all epiphyseal drilling technique, when a traditional acorn-tipped reamer over a guidepin is utilized, even if the drilling occurs very close to the physis. In addition, the risk of drilling with a FlipCutter is low, but may be greater than a traditional reamer. Clinical Relevance: Thermal-induced necrosis is a realistic concern, due to the characteristics of the distal femoral physis, and the propensity for this physis to respond poorly to injury. Our study supports that drilling near the physis can be done safely, although smaller reamers and nontraditional designs may generate higher heat. Level of Evidence: Level I—basic science.

Anterior horn lateral meniscus tear, repair, and meniscectomy.

The purpose of this study was to describe the effect of anterior horn of the lateral meniscus (AHLM) tears on tibiofemoral contact pressures and the ability to restore normal parameters with repair. Eight fresh-frozen cadaveric knees were used. The specimens were subjected to a load of 1,000 N at 0 and 30 degrees of flexion and peak pressure, force and contact area were recorded. The test was repeated for four different instances. Peak force in the lateral compartment was significantly increased at 0 degrees of knee flexion from 37 N intact to 47 N after the tear and 56 N postmeniscectomy. At 0 degrees of knee flexion, the peak pressure of the lateral meniscus was significantly increased from 1.1 MPa in the intact state to 1.9 MPa after meniscectomy. The peak pressure in the nontraumatized medial compartment was significantly increased after partial lateral meniscectomy (p < 0.05). This cadaveric study demonstrated a significant increase in tibiofemoral peak forces in both the medial and lateral compartments with a tear of the AHLM. It also showed an increase in peak contact pressure after meniscectomy. With repair, the preinjury condition peak forces were restored to normal, suggesting the importance of repairing tears of the AHLM.

Outlet Biceps Tenodesis: A New Technique for Treatment of Biceps Long Head Tendon Injury

Degeneration and tearing of the long head of the biceps brachii tendon (LHBT) are common intra-articular findings, and surgical intervention including tenodesis or tenotomy is beneficial. A new arthroscopic shoulder technique may be performed through an anterior portal while one is viewing from a posterior portal: (1) Visualize the intra-articular biceps tendon. (2) Identify the segment of the LHBT to be enlarged. (3) Use a tissue modulation wand to enlarge the tendon. (4) Evaluate the diameter of the enlarged segment. It should be twice the original diameter. (5) Cut the biceps tendon at the proximal end of the enlarged segment. (6) View the tendon within the tunnel. (7) Identify and cut the remaining stump of the biceps tendon. Seventeen cadaveric shoulders were used to compare the pullout force, stiffness, and displacement of outlet tenodesis versus tenotomy. There was a significant increase in pullout force for the outlet tenodesis group when compared with tenotomy. This technique is used to operatively treat LHBT intra-articular pathology in patients who would benefit from tenotomy and traditional biceps tenodesis and may minimize the retraction of the biceps tendon distally.