Ulnar Neuritis and Its Affect on Outcomes of Elbow Ulnar Collateral Ligament Reconstruction.

BACKGROUND: No study has specifically evaluated how ulnar neuritis and ulnar nerve transposition affect outcomes in baseball players undergoing ulnar collateral ligament (UCL) reconstruction (UCLR). PURPOSE: To evaluate the effects of ulnar neuritis and ulnar nerve transposition in baseball pitchers undergoing UCLR in regard to return to sport, time to return to sport, and need for revision or additional surgery. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: At a single institution, all consecutive baseball pitchers undergoing UCLR between 2002 and 2015 were identified. Ulnar neuritis was diagnosed preoperatively by the following criteria: ulnar nerve symptoms, Tinel sign at the elbow, symptomatic subluxation, and numbness/paresthesia in an ulnar nerve distribution of the hand. The primary outcome of the study was return to sport. The secondary outcomes of the study were time to return to sport, length of playing career, and revision or additional surgery. RESULTS: A total of 578 UCLRs were performed in baseball players; of these, 500 UCLRs were performed in pitchers. Ulnar neuritis was diagnosed in 97 (19.4%) baseball pitchers presenting with UCL injury. There were no significant differences in patient characteristics or surgical techniques performed for reconstruction between baseball pitchers with and without ulnar neuritis. In review of injury characteristics, ulnar neuritis was significantly more likely to be diagnosed in pitchers with an acute onset of UCL injury (P = .03). Transposition of the ulnar nerve was more commonly performed in players with ulnar neuritis (47%) versus those without ulnar neuritis (10%; P = .0001). The players who had ulnar neuritis and underwent UCLR had a significantly lower odds of returning to sport (odds ratio, 0.45; P = .04); however, no significant difference was found for time to return to sport and length of playing career for those with and without ulnar neuritis (P = .38 and .51, respectively). CONCLUSION: The study suggests that ulnar neuritis, when present preoperatively in baseball pitchers undergoing UCLR, may adversely affect their ability to return to sport, whereas ulnar nerve transposition at the time of UCLR does not alter the ability to return to sport.

Biomechanical Comparison of Capsular Repair, Capsular Shift, and Capsular Plication for Hip Capsular Closure: Is a Single Repair Technique Best for All?

BACKGROUND: In hip arthroscopy, the best capsular closure technique to prevent microinstability in some patients while preventing overconstraints in other patients has yet to be determined. PURPOSE: To evaluate the biomechanical effects of capsular repair, capsular shift, and combination capsular shift and capsular plication for closure of the hip capsule. STUDY DESIGN: Controlled laboratory study. METHODS: Eight cadaveric hips (4 male and 4 female hips; mean age, 55.7 years) were evaluated in 7 conditions: intact, vented, capsulotomy, side-to-side repair, side-to-side repair with capsular plication (interval closure between iliofemoral and ischiofemoral ligaments), capsular shift repair, and capsular shift repair with plication. Measurements, via a 360° goniometer, included internal and external rotation with 1.5 N·m of torque at 5° of extension and 0°, 30°, 60°, and 90° of flexion. In addition, the degree of maximum extension with 5 N·m of torque and the amount of femoral distraction with 40 N and 80 N of force were obtained. Repeated-measures analysis of variance and Tukey post hoc analyses were used to analyze differences between capsular conditions. RESULTS: At lower hip positions (5° of extension, 0° and 30° of flexion), there was a significant increase in external rotation and total rotation after capsulotomy versus the intact state (P < .05). At all hip flexion angles, there was a significant increase in external rotation, internal rotation, and total rotation as well as a significant increase in maximum extension after capsulotomy versus capsular shift with plication (P < .05 for all). At all flexion angles, both capsular closure with side-to-side repair (with or without plication) and capsular shift without capsular plication were able to restore rotation, with no significant differences compared with the intact capsule (P > .05). Among repair constructs, there were significant differences in range of motion between side-to-side repair and combined capsular shift with plication (P < .05). CONCLUSION: At all positions, significantly increased rotational motion was seen after capsulotomy. Capsular closure was able to restore rotation similar to an intact capsule. Combined capsular shift and plication may provide more restrained rotation for conditions of hip microinstability but may overconstrain hips without laxity. CLINICAL RELEVANCE: More advanced closure techniques or a combination of techniques may be needed for patients with hip laxity and microinstability. At the same time, simple repair may suffice for patients without these conditions.

Anterior Cable Reconstruction Using the Proximal Biceps Tendon for Large Rotator Cuff Defects.

Tears of the rotator cuff tendons can occur that do not allow anatomic footprint restoration yet may not be large enough to require a superior capsular reconstruction technique. Typically, these intermediate-sized tears are addressed with a medialized repair or partial repair technique. A partially repaired rotator cuff tendon, however, can lead to a high retear rate, as the repaired tendon is required to serve as both a dynamic tendon and a static ligamentous stabilizer. One potential static support, as a nearby autologous graft donor, is the proximal long head biceps tendon. The purpose of this Technical Note is to describe a surgical technique for an anterior cable reconstruction using the proximal biceps tendon for large rotator cuff defects.

Generation of Closed Transverse Fractures in Small Animals.

The most common procedure that has been developed for use in rats and mice to model fracture healing is described. The nature of the regenerative processes that may be assessed and the types of research questions that may be addressed with this model are briefly outlined. The detailed surgical protocol to generate closed simple transverse fractures is presented and general considerations when setting up an experiment using this model are described.

Is the Caprini Score Predictive of Venothromboembolism Events in Orthopaedic Fracture Patients?

OBJECTIVE: Explore the validity of the Caprini Score in orthopaedic patients with lower-extremity fractures. DESIGN: Retrospective cohort study. SETTING: Level I trauma academic medical center. PATIENTS/PARTICIPANTS: Eight hundred forty-eight patients with lower-extremity fractures from 2002 to 2015 with exclusion criteria: minors, follow-up less than 30 days. INTERVENTION: Stratify patients into 2 groups: high-risk (pelvic and acetabular fractures) and low-risk groups (isolated foot and ankle fractures). MAIN OUTCOME: Caprini Score, fracture classification, length of follow-up, deep vein thrombosis (DVT) chemoprophylaxis, and venothromboembolism (VTE) events [DVT and/or pulmonary embolism (PE)] diagnosed with objective testing. RESULTS: Eight hundred forty-eight patients (499 M; 349 F) 18-93 years of age (average 43.7) with average body mass index of 29. Three hundred high-risk and 548 low-risk patients with no differences in demographics with average follow-up of 288 days. There were 33 (3.9%) VTE events, which were more common in the high-risk group (8%: 9 DVT, 15 PE) than the low-risk group (1.6%: 8 DVT, 1 PE) (P < 0.0001). The cutoff that best-predicted VTE events based on receiver-operating curves was 12 (c = 0.74) in the high-risk group, 11 (c = 0.79) in the low-risk group, and 12 (c = 0.83) overall. CONCLUSION: There was a significant lower VTE rate found in the low-risk group, but the Caprini prediction model was not significantly different between the 2 groups. This displays that patient factors play a large role in the development of VTE events independent of injury type. The Caprini score may help identify patients who may require increased protection. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Glenohumeral Internal Rotation Deficit and Risk of Upper Extremity Injury in Overhead Athletes: A Meta-Analysis and Systematic Review.

CONTEXT: Current perception dictates that glenohumeral internal rotation deficit (GIRD) is a chronic adaptation that leads to an increased risk of pathologic conditions in the dominant shoulder or elbow of overhead athletes. OBJECTIVE: To determine whether adaptations in glenohumeral range of motion in overhead athletes lead to injuries of the upper extremity, specifically in the shoulder or elbow. DATA SOURCES: An electronic database search was performed using Medline, Embase, and SportDiscus from 1950 to 2016. The following keywords were used: GIRD, glenohumeral internal rotation deficit, glenohumeral deficit, shoulder, sport, injury, shoulder joint, baseball, football, racquet sports, volleyball, javelin, cricket, athletic injuries, handball, lacrosse, water polo, hammer throw, and throwing injury. STUDY SELECTION: Seventeen studies met the inclusion criteria for this systematic review. Of those 17 studies, 10 included specific range of motion measurements required for inclusion in the meta-analysis. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 4. DATA EXTRACTION: Data on demographics and methodology as well as shoulder range of motion in various planes were collected when possible. The primary outcome of interest was upper extremity injury, specifically shoulder or elbow injury. RESULTS: The systematic review included 2195 athletes (1889 males, 306 females) with a mean age of 20.8 years. Shoulders with GIRD favored an upper extremity injury, with a mean difference of 3.11° (95% CI, -0.13° to 6.36°; P = 0.06). Shoulder total range of motion suggested increased motion (mean difference, 2.97°) correlated with no injury ( P = 0.11), and less total motion (mean difference, 1.95°) favored injury ( P = 0.14). External rotational gain also favored injury, with a mean difference of 1.93° ( P = 0.07). CONCLUSION: The pooled results of this systematic review and meta-analysis did not reach statistical significance for any shoulder motion measurement and its correlation to shoulder or elbow injury. Results, though not reaching significance, favored injury in overhead athletes with GIRD, as well as rotational loss and external rotational gain.

Repair of the Thumb Ulnar Collateral Ligament With Suture Tape Augmentation.

One of the most commonly injured structures of the thumb metacarpophalangeal (MCP) joint is the ulnar collateral ligament (UCL). An acute injury of this ligament is often amenable to primary repair. Despite the favorable outcomes of primary repair, the thumb is often restricted during initial healing of the ligament with immobilization and delayed rehabilitation. We present a novel technique to augment the repair of the UCL with suture tape to provide immediate biomechanical support and strength during the critical time of ligament healing. We describe the surgical technique of suture tape augmentation for thumb UCL repair. At the ulnar aspect of the thumb MCP joint, a longitudinal midaxial incision is made. Subsequently, the adductor pollicis aponeurosis and extensor mechanism are identified, incised, and retracted. The UCL is exposed and usually torn off the volar-ulnar base of the proximal phalanx. A 2.5-mm PushLock anchor loaded with 1.3-mm SutureTape and 3-0 FiberWire suture, is placed into a hole at the volar-ulnar base of the proximal phalanx after preparation with a 1.8-mm drill bit. The 3-0 FiberWire is used for direct repair of the ligament. Both tails of the 1.3-mm SutureTape is then brought proximally over the ligament and loaded into a 3.5-mm SwiveLock anchor. A 3.2-mm drill bit is then used to make a hole at the ulnar aspect of the metacarpal head, just proximal to the attachment of the proximal UCL. With the thumb MCP joint held in at least 30 degrees of flexion, the tape-loaded 3.5-mm SwiveLock anchor is inserted into metacarpal head. Reinforcement of the repair is then carried out with fine absorbable suture to surrounding capsular tissue. We present a representative case of a professional basketball player treated with this novel procedure. After the surgical repair, the patient was placed in a plaster splint for 3 days to immobilize the thumb and wrist. At 3 days postsurgery, the splint was removed and therapy initiated. Practice drills were initiated at 1 week postsurgery with the use of a removable hand-based thumb spica custom splint. During the entire postoperative period, the left thumb MCP joint had excellent stability to radial stress at full extension and 30 degrees of flexion. In addition, at 3 weeks postsurgery, the patient was able to oppose the thumb tip to the palmar-digital crease of the small finger and MCP joint motion was 0 to 50 degrees. The patient began strengthening exercises at this time, along with the ability to participate in all position-specific drills. At 5 weeks postsurgery, the patient was cleared to return to full play, without use of a splint. At 37 days postsurgery, the patient returned to competitive play. During competitive play, the player completed the entire remaining season of 25 games as well as extended competition into the playoffs of 7 games without further incident or time missed. At the latest follow-up, the patient is 6 months postprocedure and continues to remain asymptomatic with full participation in playing sports. During the critical time of ligament healing, the UCL repair can be enhanced with synthetic material to obviate the need for prolonged postoperative immobilization. We offer a novel surgical technique that enhances primary repair of the thumb UCL through appended biomechanical support. Under these circumstances, with structural support augmentation, the recovery and rehabilitation process can be expedited for patients to allow an earlier return to activities.

External validation of the clinical indications of computed tomography (CT) of the head in patients with low-energy geriatric hip fractures.

INTRODUCTION: On evaluation of the clinical indications of computed tomography (CT) scan of head in the patients with low-energy geriatric hip fractures, Maniar et al. identified physical evidence of head injury, new onset confusion, and Glasgow Coma Scale (GCS)<15 as predictive risk factors for acute findings on CT scan. The goal of the present study was to validate these three criteria as predictive risk factors for a larger population in a wider geographical distribution. PATIENTS AND METHODS: Patients ≥65 years of age with low-energy hip fractures from 6 trauma centers in a wide geographical distribution in the United States were included in this study. In addition to the relevant patient demographic findings, the above mentioned three criteria and acute findings on head CT scan were gathered as categorical variables. RESULTS: In total 799 patients from 6 centers were included in the study. There were 67 patients (8.3%) with positive acute findings on head CT scan. All of these patients (100%) had at least one criteria positive. There were 732 patients who had negative acute findings on head CT scan with 376 patients (51%) having at least one criteria positive and 356 patients (49%) having no criteria positive. Sensitivity of 100% and negative predictive value of 100% was observed to predict negative acute findings on head CT scan when all the three criteria were negative. CONCLUSION: With the observed 100% sensitivity and 100% negative predictive value, physical evidence of acute head injury, acute retrograde amnesia, and GCS<15 can be recommended as a clinical decision guide for the selective use of head CT scans in geriatric patients with low energy hip fractures. All the patients with positive acute head CT findings can be predicted in the presence of at least one positive criterion. In addition, if these criteria are used as a pre-requisite to order the head CT, around 50% of the unnecessary head CT scans can be avoided.

Anterior Cervical Infection: Presentation and Incidence of an Uncommon Postoperative Complication.

STUDY DESIGN: Retrospective multi-institutional case series. OBJECTIVE: The anterior cervical discectomy and fusion (ACDF) affords the surgeon the flexibility to treat a variety of cervical pathologies, with the majority being for degenerative and traumatic indications. Limited data in the literature describe the presentation and true incidence of postoperative surgical site infections. METHODS: A retrospective multicenter case series study was conducted involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network, selected for their excellence in spine care and clinical research infrastructure and experience. Medical records for 17 625 patients who received cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, inclusive, were reviewed to identify the occurrence of 21 predefined treatment complications. Patients who underwent an ACDF were identified in the database and reviewed for the occurrence of postoperative anterior cervical infections. RESULTS: A total of 8887 patients were identified from a retrospective database analysis of 21 centers providing data for postoperative anterior cervical infections (17/21, 81% response rate). A total of 6 postoperative infections after ACDF were identified for a mean rate of 0.07% (range 0% to 0.39%). The mean age of patients identified was 57.5 (SD = 11.6, 66.7% female). The mean body mass index was 22.02. Of the total infections, half were smokers (n = 3). Two patients presented with myelopathy, and 3 patients presented with radiculopathic-type complaints. The mean length of stay was 4.7 days. All patients were treated aggressively with surgery for management of this complication, with improvement in all patients. There were no mortalities. CONCLUSION: The incidence of postoperative infection in ACDF is exceedingly low. The management has historically been urgent irrigation and debridement of the surgical site. However, due to the rarity of this occurrence, guidance for management is limited to retrospective series.

Misplaced Cervical Screws Requiring Reoperation.

STUDY DESIGN: A multicenter, retrospective case series. OBJECTIVE: In the past several years, screw fixation of the cervical spine has become commonplace. For the most part, this is a safe, low-risk procedure. While rare, screw backout or misplaced screws can lead to morbidity and increased costs. We report our experiences with this uncommon complication. METHODS: A multicenter, retrospective case series was undertaken at 23 institutions in the United States. Patients were included who underwent cervical spine surgery from January 1, 2005, to December 31, 2011, and had misplacement of screws requiring reoperation. Institutional review board approval was obtained at all participating institutions, and detailed records were sent to a central data center. RESULTS: A total of 12 903 patients met the inclusion criteria and were analyzed. There were 11 instances of screw backout requiring reoperation, for an incidence of 0.085%. There were 7 posterior procedures. Importantly, there were no changes in the health-related quality-of-life metrics due to this complication. There were no new neurologic deficits; a patient most often presented with pain, and misplacement was diagnosed on plain X-ray or computed tomography scan. The most common location for screw backout was C6 (36%). CONCLUSIONS: This study represents the largest series to tabulate the incidence of misplacement of screws following cervical spine surgery, which led to revision procedures. The data suggest this is a rare event, despite the widespread use of cervical fixation. Patients suffering this complication can require revision, but do not usually suffer neurologic sequelae. These patients have increased cost of care. Meticulous technique and thorough knowledge of the relevant anatomy are the best means of preventing this complication.

A Multicenter Study of the Presentation, Treatment, and Outcomes of Cervical Dural Tears.

STUDY DESIGN: Retrospective multicenter case series study. OBJECTIVE: Because cervical dural tears are rare, most surgeons have limited experience with this complication. A multicenter study was performed to better understand the presentation, treatment, and outcomes following cervical dural tears. METHODS: Multiple surgeons from 23 institutions retrospectively identified 21 rare complications that occurred between 2005 and 2011, including unintentional cervical dural tears. Demographic data and surgical history were obtained. Clinical outcomes following surgery were assessed, and any reoperations were recorded. Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA), Nurick classification (NuC), and Short-Form 36 (SF36) scores were recorded at baseline and final follow-up at certain centers. All data were collected, collated, and analyzed by a private research organization. RESULTS: There were 109 cases of cervical dural tears among 18 463 surgeries performed. In 101 cases (93%) there was no clinical sequelae following successful dural tear repair. There were statistical improvements (P < .05) in mJOA and NuC scores, but not NDI or SF36 scores. No specific baseline or operative factors were found to be associated with the occurrence of dural tears. In most cases, no further postoperative treatments of the dural tear were required, while there were 13 patients (12%) that required subsequent treatment of cerebrospinal fluid drainage. Analysis of those requiring further treatments did not identify an optimum treatment strategy for cervical dural tears. CONCLUSIONS: In this multicenter study, we report our findings on the largest reported series (n = 109) of cervical dural tears. In a vast majority of cases, no subsequent interventions were required and no clinical sequelae were observed.

C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases.

STUDY DESIGN: A multicenter, retrospective review of C5 palsy after cervical spine surgery. OBJECTIVE: Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery. METHODS: We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ2 tests or Fisher exact tests for categorical variables. RESULTS: Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%). CONCLUSION: C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

Prevalence and Outcomes in Patients Undergoing Reintubation After Anterior Cervical Spine Surgery: Results From the AOSpine North America Multicenter Study on 8887 Patients.

STUDY DESIGN: A multicenter, retrospective cohort study. OBJECTIVE: To evaluate clinical outcomes in patients with reintubation after anterior cervical spine surgery. METHODS: A total of 8887 patients undergoing anterior cervical spine surgery were enrolled in the AOSpine North America Rare Complications of Cervical Spine Surgery study. Patients with or without complications after surgery were included. Demographic and surgical information were collected for patients with reintubation. Patients were evaluated using a variety of assessment tools, including the modified Japanese Orthopedic Association scale, Nurick score, Neck Disability Index, and Short Form-36 Health Survey. RESULTS: Nine cases of postoperative reintubation were identified. The total prevalence of this complication was 0.10% and ranged from 0% to 0.59% across participating institutions. The time to development of airway symptoms after surgery was within 24 hours in 6 patients and between 5 and 7 days in 3 patients. Although 8 patients recovered, 1 patient died. At final follow-up, patients with reintubation did not exhibit significant and meaningful improvements in pain, functional status, or quality of life. CONCLUSIONS: Although the prevalence of reintubation was very low, this complication was associated with adverse clinical outcomes. Clinicians should identify their high-risk patients and carefully observe them for up to 2 weeks after surgery.

Alignment After Intramedullary Nailing of Distal Tibia Fractures Without Fibula Fixation.

OBJECTIVE: To evaluate the efficacy of intramedullary nailing of distal tibia fractures using modern techniques, without fibula fixation, in obtaining and maintaining alignment. DESIGN: Retrospective case review. SETTING: Level-I academic trauma center. PATIENTS: One hundred thirty-two consecutive patients with distal tibia fractures. INTERVENTION: Intramedullary nail of distal tibia fracture, without fibula fixation, was performed in consecutive patients using modern reduction techniques. MAIN OUTCOME MEASURES: Malalignment and malunion were defined as >5 degrees of varus/valgus angulation or anterior/posterior angulation on the initial postoperative or final anteroposterior and lateral x-rays. RESULTS: There were 122 consecutive patients (86 men and 36 women) 16-93 years of age (average, 43 years) with 36 (30%) open and 85 (70%) closed fractures with complete follow-up. Mechanism of injury did not predict the presence or level of fibula fracture. Upon presentation, varus/valgus and procurvatum/recurvatum angulation was greatest when the fibula was fractured at the level of the tibia fracture (P = 0.001 and 0.028). The most common intraoperative reduction aids were nailing in relative extension, transfixion external fixation, and clamps at the fracture site. The OTA fracture type or level/presence of fibula fracture did not influence malalignment (P = 0.86 and 0.66), malunion (P = 0.81 and 0.79), or the change in alignment during union, which averaged 0.9 degrees. CONCLUSIONS: We found an overall low rate of both malalignment (2%) and malunion (3%) after intramedullary nailing of distal tibial shaft fracture without fibula fixation. We conclude that when modern nailing techniques are used, which allow for confirmation of reduction by visualization in fluoroscopy, from nail placement to distal interlocking, fibula fixation is not necessary to obtain or maintain alignment. Furthermore, standard 2 medial to lateral screws distally afford adequate stability to hold the reduction during union with a 0.9-degree difference in the initial postoperative and final united films. LEVEL OF EVIDENCE: Therapeutic level IV. See Instructions for Authors for a complete description of levels of evidence.

Outcomes after plating of olecranon fractures: A multicenter evaluation.

INTRODUCTION: The aim of this study was to report the physical and functional outcomes after open reduction internal fixation of the olecranon in a large series of patients with region specific plating across multiple centres. PATIENTS/METHODS: Between January 2007 and January 2014, 182 consecutive patients with a displaced olecranon fracture treated with open reduction internal fixation were included in this study. Retrospective review across four trauma centres collected elbow range of motion, DASH scores, hardware complications, and hardware removal. Postoperative visits in the outpatient clinic were at two, six, and twenty-four weeks. After 24 weeks, patients were eligible for hardware removal if symptomatic. All patients were contacted, at least 1 year following surgery, to determine if hardware was removed. RESULTS: 182 patients (75 women, 105 men) average age 50 (16-89) with 162 closed and 19 open displaced olecranon fractures were treated with one region specific plate. Nineteen were lost to followup leaving 163 for analysis with all patients united. The most common deficiency was a lack of full extension with 39% lacking at least 10° of extension. Hardware was asymptomatic in 67%, painful upon leaning in 20%, and restricted activities in 11% resulting in a 15% rate of hardware removal. Hardware complaints were more common if a screw was placed in the corner of the plate (P=0.004). When symptomatic, the area of the plate that was bothersome encompassed the whole plate in 39%, was at the edge of the plate in 33%, and was a screw head in 28%. The DASH scores, collected at final follow-up of 24 weeks, was 10.1±16, indicating moderate disability was still present. Patients who lacked 10° of extension had a DASH of 12.3 as compared with 10.5 for those with near full extension, but this was not significant (P=0.5). CONCLUSION: Plating of the olecranon leads to predictable union. The most common complication was lack of full extension with 39% lacking more than 10°, although this did not have any effect on DASH scores. Overall results indicate that disability still exists after 6 months with an average DASH score of 10. LEVEL OF EVIDENCE: Therapeutic level III.

Overview of skeletal repair (fracture healing and its assessment).

The study of postnatal skeletal repair is of immense clinical interest. Optimal repair of skeletal tissue is necessary in all varieties of elective and reparative orthopedic surgical treatments. However, the repair of fractures is unique in this context in that fractures are one of the most common traumas that humans experience and are the end-point manifestation of osteoporosis, the most common chronic disease of aging. In the first part of this introduction the basic biology of fracture healing is presented. The second part discusses the primary methodological approaches that are used to examine repair of skeletal hard tissue and specific considerations for choosing among and implementing these approaches.

Generation of closed transverse fractures in small animals.

The most common procedure that has been developed for use in rats and mice to model fracture healing is described. The nature of the regenerative processes that may be assessed and the types of research questions that may be addressed with this model are briefly outlined. The detailed surgical protocol to generate closed simple transverse fractures is presented, and general considerations when setting up an experiment using this model are described.

ALOX5AP and LTA4H polymorphisms modify augmentation of bronchodilator responsiveness by leukotriene modifiers in Latinos.

BACKGROUND: Understanding the effects of interactions between multiple genes and asthma medications may aid in the understanding of the heterogeneous response to asthma therapies. OBJECTIVE: To identify modulating effects of arachidonate 5-lipoxygenase-activating protein (ALOX5AP) and leukotriene A(4) hydrolase (LTA4H) gene polymorphisms on the drug-drug interaction between leukotriene modifiers and albuterol in Mexicans and Puerto Ricans. METHODS: In a cross-sectional study of 293 Mexicans and 356 Puerto Ricans with asthma, ALOX5AP and LTA4H genes were sequenced, and interactions between gene polymorphisms and bronchodilator responsiveness to albuterol were compared between leukotriene modifier users and nonusers. RESULTS: In heterozygotes and homozygotes for the minor allele at LTA4H single nucleotide polymorphism (SNP) rs2540491 and heterozygotes for the major allele at LTA4H SNP rs2540487, leukotriene modifier use was associated with a clinically significant increase in percent change in FEV(1) after albuterol administration of 7.10% (P = .002), 10.06% (P = .001), and 10.03% (P < .001), respectively. Presence of the major allele at ALOX5AP SNP rs10507391 or the minor allele at ALOX5AP SNP rs9551963 augmented this response. When stratified by ethnicity, these findings held true for Puerto Ricans but not Mexicans. CONCLUSION: LTA4H and ALOX5AP gene polymorphisms modify the augmentation of bronchodilator responsiveness by leukotriene modifiers in Puerto Ricans but not Mexicans with asthma.

Genetic ancestry modifies pharmacogenetic gene-gene interaction for asthma.

OBJECTIVE: A recent admixture mapping analysis identified interleukin 6 (IL6) and IL6 receptor (IL6R) as candidate genes for inflammatory diseases. In the airways during allergic inflammation, IL6 signaling controls the production of proinflammatory and anti-inflammatory factors. In addition, albuterol, a commonly prescribed asthma therapy, has been shown to influence IL6 gene expression. Therefore, we reasoned that interactions between the IL6 and IL6R genes might be associated with bronchodilator drug responsiveness to albuterol in asthmatic patients. METHODS: Four functional IL6 single nucleotide polymorphisms (SNPs) and a nonsynonymous IL6R SNP were genotyped in 700 Mexican and Puerto Rican asthma families and in 443 African-American asthma cases and controls. Both family-based association tests and linear regression models were used to assess the association between individual SNPs and haplotypes with bronchodilator response. Gene-gene interactions were tested by using multiple linear regression analyses. RESULTS: No single SNP was consistently associated with drug response in all the three populations. However, on the gene level, we found a consistent IL6 and IL6R pharmacogenetic interaction in the three populations. This pharmacogenetic gene-gene interaction was contextual and dependent upon ancestry (racial background). This interaction resulted in higher drug response to albuterol in Latinos, but lower drug response in African-Americans. Herein, we show that there is an effect modification by ancestry on bronchodilator responsiveness to albuterol. CONCLUSION: Genetic variants in the IL6 and IL6R genes act synergistically to modify the bronchodilator drug responsiveness in asthma and this pharmacogenetic interaction is modified by the genetic ancestry.