Factors Affecting Targeted Sequencing of 353 Nuclear Genes From Herbarium Specimens Spanning the Diversity of Angiosperms.

The world's herbaria collectively house millions of diverse plant specimens, including endangered or extinct species and type specimens. Unlocking genetic data from the typically highly degraded DNA obtained from herbarium specimens was difficult until the arrival of high-throughput sequencing approaches, which can be applied to low quantities of severely fragmented DNA. Target enrichment involves using short molecular probes that hybridise and capture genomic regions of interest for high-throughput sequencing. In this study on herbariomics, we used this targeted sequencing approach and the Angiosperms353 universal probe set to recover up to 351 nuclear genes from 435 herbarium specimens that are up to 204 years old and span the breadth of angiosperm diversity. We show that on average 207 genes were successfully retrieved from herbarium specimens, although the mean number of genes retrieved and target enrichment efficiency is significantly higher for silica gel-dried specimens. Forty-seven target nuclear genes were recovered from a herbarium specimen of the critically endangered St Helena boxwood, Mellissia begoniifolia, collected in 1815. Herbarium specimens yield significantly less high-molecular-weight DNA than silica gel-dried specimens, and genomic DNA quality declines with sample age, which is negatively correlated with target enrichment efficiency. Climate, taxon-specific traits, and collection strategies additionally impact target sequence recovery. We also detected taxonomic bias in targeted sequencing outcomes for the 10 most numerous angiosperm families that were investigated in depth. We recommend that (1) for species distributed in wet tropical climates, silica gel-dried specimens should be used preferentially; (2) for species distributed in seasonally dry tropical climates, herbarium and silica gel-dried specimens yield similar results, and either collection can be used; (3) taxon-specific traits should be explored and established for effective optimisation of taxon-specific studies using herbarium specimens; (4) all herbarium sheets should, in future, be annotated with details of the preservation method used; (5) long-term storage of herbarium specimens should be in stable, low-humidity, and low-temperature environments; and (6) targeted sequencing with universal probes, such as Angiosperms353, should be investigated closely as a new approach for DNA barcoding that will ensure better exploitation of herbarium specimens than traditional Sanger sequencing approaches.

Incidence of injury based on sports participation in high school athletes.

OBJECTIVES: Youth participation in competitive athletics has significantly increased in the past two decades. There has also been a recent rise in the number of sports injuries that physicians are seeing in young athletes. The objective of this study was to assess the likelihood of sports injuries based on several risk factors in a general sample of athletes at a suburban-area high school. METHODS: This was a cross-sectional study. An online survey was distributed to 2,200 student-athletes at a local high school with a mean age of 15.9 years. Four hundred eighty four (22%) complete responses were received. Data collected in the survey included demographics, frequency of sports participation, level of participation, types of sports played, participation in cross-training, injuries incurred, use of non-steroidal anti-inflammatory drugs, and treatment for sports injuries. RESULTS: Athletes played an average of 1.6 different sports. The average number of hours of participation in sports annually was 504.3 ± 371.6 hours. The average total number of sports injuries experienced by athletes in our study was 1.7 per participant. 80.8% of respondents reported having sustained at least one sports injury. A higher total number of hours per year of sports participation and playing a contact sport were significantly associated with more reported lifetime sports injuries. Older age, playing a contact sport, and playing on a travel/club team were associated with students using NSAIDs for sports injuries. Older age, playing a contact sport, and doing cross training are also associated with having had surgery for a sports injury. CONCLUSIONS: Although more hours of participation and playing a contact sport may lead to an increased number of injuries, this risk must be weighed against the myriad of benefits that sports provide for young athletes.

Biomechanical comparison of 3 methods to repair pectoralis major ruptures.

BACKGROUND: Pectoralis major ruptures are closely associated with weight lifting and participation in sports. The anatomy of the pectoralis major tendon is unique with an elongated thin footprint requiring multiple points of fixation to restore the native anatomy. Multiple options exist for tendon repairs, but the strongest construct has yet to be identified. PURPOSE: The intent of this study was to compare the load to failure of bone trough, cortical button, and suture anchor repairs of the pectoralis major tendon in the extended and abducted position. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty fresh-frozen cadaveric shoulders were divided equally into 3 groups based on the repair technique to be performed. Bone mineral density of the surgical neck of the proximal humerus was assessed before each repair. Bone trough, suture anchor, and cortical button repairs were performed as dictated by computerized randomization. Each specimen was loaded to failure and mode of failure was noted. RESULTS: The majority of failures occurred through the suture used for tendon repair. One specimen in the bone trough group failed via fracture of the proximal humerus. The suture anchor group failed at the implant in 5 of 9 specimens and through the suture in 4 of 9 specimens. Load to failure was greatest in bone trough repairs at 596 N, followed by cortical button at 494 N, and finally suture anchor repairs with 383 N. Load to failure was significantly greater in the bone trough group when compared with suture anchor repairs (P = .007). No correlation was found between bone mineral density and load to failure. CONCLUSION: Bone trough repair of the pectoralis major tendon was stronger than suture anchor repair. CLINICAL RELEVANCE: Identification of the strongest repair may help guide surgical repair.

Heat generated with pegged or keeled glenoid components fixed with defined amounts of cement.

Glenoid component loosening is a common complication of total shoulder arthroplasty and has been associated with the progression of radiolucent lines at the glenoid bone-cement interface. Generation of heat during the exothermic reaction of cement curing may cause osteonecrosis of bone, potentially leading to the development of radiolucent lines. The purpose of this study was to measure the heat generated with various defined amounts of cement used for glenoid component fixation.Ten fresh-frozen cadaver scapulas were randomized to receive a keeled or pegged component with 1, 2, 3, 5, or 7 g of cement for fixation. An infrared camera was used to record the surface temperature generated during the cement curing process to an accuracy of ±2.0°C. Computed tomography was used to evaluate the cement mantle. The maximum temperatures generated did not exceed the critical value for osteonecrosis (56°C) in any of the specimens. The 4 specimens without a complete mantle were those fixed with a smaller quantity of cement (1, 2, or 3 g), and the largest cement mantle thicknesses were observed with the use of 7 g of cement.Up to 7 g of cement can be used without significant concern for thermal necrosis. Incomplete cement mantles were observed when ≤3 g of cement was used for fixation. Our results suggest that surgeons should use >3 g of cement to avoid incomplete cement mantles and that up to 7 g of cement can safely be used for glenoid fixation.

Biologic and pharmacologic augmentation of rotator cuff repairs.

As rotator cuff repair techniques have improved, failure of the tendon to heal to the proximal humerus is less likely to occur from weak tendon-to-bone fixation. More likely causes of failure include biologic factors such as intrinsic tendon degeneration, fatty atrophy, fatty infiltration of muscle, and lack of vascularity of the tendons. High failure rates have led to the investigation of biologic augmentation to potentially enhance the healing response. Histologic studies have shown that restoration of the rotator cuff footprint during repair can help reestablish the enthesis. In animal models, growth factors and their delivery scaffolds as well as tissue engineering have shown promise in decreasing scar tissue while maintaining biomechanical strength. Platelet-rich plasma may be a safe adjuvant to rotator cuff repair, but it has not been shown to improve healing or function. Many of these strategies need to be further defined to permit understanding of, and to optimize, the biologic environment; in addition, techniques need to be refined for clinical use.

Infection after shoulder surgery.

Infection after shoulder surgery is rare but potentially devastating. Normal skin flora, including Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes, are the most commonly isolated pathogens. Perioperative measures to prevent infection are of paramount importance, and clinical acumen is necessary for diagnosis. Superficial infections may be managed with local wound measures and antibiotics; deep infections require surgical débridement in combination with antibiotic treatment. Treating physicians must make difficult decisions regarding antibiotic duration and the elimination of the offending organisms by resection arthroplasty, direct implant exchange, or staged revision arthroplasty. Eradication of a deep infection is usually successful, but the course of treatment is often protracted, and tissue destruction and scar may adversely affect functional outcome.

Nonoperative treatment of superior labrum anterior posterior tears: improvements in pain, function, and quality of life.

BACKGROUND: Although there are multiple reports documenting successful outcomes with operative treatment of superior labrum anterior posterior (SLAP) tears, there are few reports on the results of nonoperative treatment. HYPOTHESIS: Nonoperative treatment of SLAP tears will result in improved outcomes over pretreatment values using validated, patient-derived outcome instruments. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 371 patients with a diagnosis of labral tear at our institution were mailed a questionnaire that included the following validated, patient-derived outcome assessment instruments: Short Form 36 (SF-36), European Quality of Life measure (EuroQol), visual analog pain scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, and simple shoulder test (SST). Sixty-six surveys did not reach the patients because of incorrect addresses, and 50 surveys were returned, for a 16.4% (50 of 305) response rate. Of the patients with a clinically documented SLAP lesion (positive O'Brien test, pain at the bicipital groove, and positive magnetic resonance imaging) and sufficient follow-up data (minimum 1 year), 39 patients who met the criteria returned the survey and 19 had nonoperative treatment. Twenty patients (51%) from the overall surveyed group were considered nonoperative treatment failures and had arthroscopic surgical reconstruction. Nonoperative treatment consisted of nonsteroidal anti-inflammatory drugs and a physical therapy protocol focused on scapular stabilization exercises and posterior capsular stretching. Statistical analysis was performed using the paired t test; values of P < .05 were considered significant. RESULTS: At an average follow-up of 3.1 years, function improved significantly (ASES function 30.8 to 45.0 [P < .001]; ASES total 58.5 to 84.7 [P = .001], SST 8.3 to 11.0 [P = .02]) in those patients with successful nonoperative treatment. Quality of life also improved after treatment (EuroQol 0.76 to 0.89, P = .009). Pain relief was significant, as VAS pain scores decreased from 4.5 to 2.1 (P = .043). All patients with successful nonoperative treatment returned to sports. Seventy-one percent of all athletes were able to return to preparticipation levels, but only 66% of overhead athletes returned to their sport at the same or higher level. CONCLUSION: Using validated, patient-derived outcome instruments, the present study shows that successful nonoperative treatment of superior labral tears results in improved pain relief and functional outcomes compared with pretreatment assessments. Although 20 patients (51%) in this group elected surgery and may be considered nonoperative treatment failures, those patients with successful nonoperative treatment had significant improvements in pain, function, and quality of life. Return to sports was comparable with patients with successful surgical treatment, although return to overhead sports at the same level was difficult to achieve (66%). Based on these findings, a trial of nonoperative treatment may be considered in patients with the diagnosis of isolated superior labral tear. In overhead athletes and in those patients where pain relief and functional improvement is not achieved, surgical treatment should be considered.

Arthroscopic distal clavicle resection: a biomechanical analysis of resection length and joint compliance in a cadaveric model.

PURPOSE: The purposes of this study were to assess the effects of a distal clavicle resection of less than 5 mm on bony contact and compliance in the acromioclavicular (AC) joint and to localize areas of persistent contact in the AC joint. The hypothesis of this study was that AC contact can be avoided by excising less than 5 mm of bone from the distal clavicle. METHODS: Ten human AC joints underwent compressive loading of the distal clavicle into the acromion after the following: disk excision, distal clavicle resection of 2.5 mm, and distal clavicle resection of 5 mm. The joint resistance force, stiffness, and presence and location of contact were monitored. RESULTS: Excising 2.5 mm or less resulted in no bone-to-bone abutment in 6 of 10 specimens. A 5-mm resection resulted in successful decompression in all specimens. The specimens that required a 5-mm resection had minimal contact after the 2.5-mm resection (inferior-posterior quadrant only). AC joint stiffness decreased significantly with increasing amounts of clavicular resection (P = .01). CONCLUSIONS: A 5-mm distal clavicle resection guaranteed no abutment but decreased joint stiffness. Persistent contact occurred only in the inferior-posterior quadrant of the joint after a 2.5-mm resection. CLINICAL RELEVANCE: These findings support the efficacy of a 5-mm distal clavicle resection for eliminating bony contact but suggest that there is a bony contribution to AC joint stiffness. A resection of 2.5 to 5.0 mm could be adequate if care is taken to excise a greater depth of bone in the inferior-posterior quadrant.

Two-part surgical neck fractures of the proximal part of the humerus. A biomechanical evaluation of two fixation techniques.

BACKGROUND: Successful internal fixation of fractures of the surgical neck of the humerus can be difficult to achieve because of osteopenia of the proximal aspect of the humerus. The purpose of this study was to compare the biomechanical stability of a proximal humeral intramedullary nail and a locking plate for the treatment of a comminuted two-part fracture of the surgical neck in a human cadaver model. METHODS: Twenty-four cadaveric humeri were instrumented with use of either a titanium proximal humeral nail (PHN) or a 3.5-mm locking compression plate for the proximal part of the humerus (LCP-PH). The specimens were matched by bone mineral density and were separated into four experimental groups with six humeri in each: PHN bending, LCP-PH bending, PHN torsion, or LCP-PH torsion. Comminuted fractures of the surgical neck were simulated by excising a 10-mm wedge of bone. Bending specimens were cyclically loaded from 0 to 7.5 Nm of varus bending moment at the fracture site. Torsion specimens were cyclically loaded to +/-2 Nm of axial torque. The mean and maximum displacement in bending, mean and maximum angular rotation in torsion, and stiffness of the bone-implant constructs were compared. RESULTS: In bending, the LCP-PH group demonstrated significantly less mean displacement of the distal fragment than did the PHN group over 5000 cycles (p = 0.002). In torsion, the LCP-PH group demonstrated significantly less mean angular rotation than did the PHN group over 5000 cycles (p = 0.04). A significant number of specimens in the PHN group failed prior to reaching 5000 cycles (p = 0.04). The LCP-PH implant created a significantly stiffer bone-implant construct than did the PHN implant (p = 0.007). CONCLUSIONS: The LCP proximal humeral plate demonstrated superior biomechanical characteristics compared with the proximal humeral nail when tested cyclically in both cantilevered varus bending and torsion. The rate of early failure of the proximal humeral nail could reflect the high moment transmitted to the locking proximal screw-bone interface in this implant. CLINICAL RELEVANCE: The high failure rate in torsion of the proximal humeral nail-bone construct is concerning, and, with relatively osteoporotic bone and early motion, the results could be poor.

Dog and cat bites to the hand: treatment and cost assessment.

PURPOSE: To assess the demographic patterns, clinical morbidity, and treatment costs associated with domestic animal bites to the hand. METHODS: A retrospective review was performed on 111 patients who suffered either a dog or cat bite to the hand. Demographic data were collected for both the patient and the animal involved. RESULTS: The patient population had suffered 71 dog bites and 40 cat bites. Two scenarios were identified that increased the likelihood of a bite: (1) attempting to separate fighting animals and (2) attempting to aid an injured animal. More than half of the victims (61 of 111) were bitten by an animal with which they were familiar. Bite injuries ranged from relatively minor wounds to major injuries that included open fractures, persistent deep infection including osteomyelitis, nerve laceration, tendon laceration, or tissue loss. Approximately two thirds of patients required hospital admission at least for intravenous antibiotics. Approximately one third of animal bite victims required at least 1 surgical procedure. Thirteen patients required long-term intravenous antibiotics and/or multiple surgeries and incurred medical expenses in excess of dollar 77,000. CONCLUSIONS: Domestic animal bites to the hand are common injuries that can produce considerable morbidity. Stray animals did not account for the majority of incidents. Bite prevention strategies should focus on careful handling of animals that are fighting or injured. Animal bite wounds often require intravenous antibiotics and hospitalization and the cost of care for deep infections can be enormous. Our patient population was selected from a small geographic area over a relatively short collection period, suggesting that domestic animal bite injuries may represent a major public health issue. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic, Level IV.

Infant and child motor development.

Identifying infant and child developmental delay is a skill important for orthopaedic surgeons to master because they often are asked to distinguish between normal and abnormal movement. An emphasis has been placed on early detection and referral for intervention, which has been shown to enhance the lives of the infant or child and his or her family. Appropriate recognition of delay is necessary for referral to early intervention services, which serve to help these children overcome or improve motor dysfunction and to help families grow more confident in caring for children with special needs. We define early intervention, discuss normal and abnormal motor development, and provide useful examination tools to assess motor development.