Knotless All-Suture, Soft Anchor Bankart Repair Results in Excellent Patient-Reported Outcomes, High Patient Satisfaction, and Acceptable Recurrent Instability Rates at Minimum 2-Year Follow-Up.

PURPOSE: To evaluate minimum 2-year outcomes after arthroscopic knotless all-suture soft anchor Bankart repair in patients with anterior shoulder instability. METHODS: This was a retrospective case series of patients who underwent Bankart repair using soft, all-suture, knotless anchors (FiberTak anchors) from 10/2017 to 06/2019. Exclusion criteria were concomitant bony Bankart lesion, shoulder pathology other than that involving the superior labrum or long head biceps tendon, or previous shoulder surgery. Scores collected preoperatively and postoperatively included SF-12 PCS, ASES, SANE, QuickDASH, and patient satisfaction with various sports participation questions. Surgical failure was defined as revision instability surgery or redislocation requiring reduction. RESULTS: A total of 31 active patients, 8 females and 23 males, with a mean age of 29 (range: 16-55) years were included. At a mean of 2.6 years (range: 2.0-4.0), patient-reported outcomes significantly improved over preoperative levels. ASES score improved from 69.9 to 93.3 (P < .001), SANE improved from 56.3 to 93.8 (P < .001), QuickDASH improved from 32.1 to 6.3 (P < .001) and SF-12 PCS improved from 45.6 to 55.7 (P < .001). Median patient postoperative satisfaction was 10/10 (range: 4-10). Patients reported a significant improvement sports participation (P < .001), pain with competition (P = .001), ability to compete in sports (P < .001), painless use of arm for overhead activities (P = .001), and shoulder function during recreational sporting activity (P < .001). Postoperative shoulder redislocations were reported in 4 cases (12.9%)-all after major trauma-with 2 patients progressing to Latarjet (6.45%) at 2 and 3 years postoperatively. There were no cases of postoperative instability without major trauma. CONCLUSIONS: Knotless all-suture, soft anchor Bankart repair resulted in excellent patient-reported outcomes, high patient satisfaction, and acceptable recurrent instability rates, in this series of active patients. Redislocation after arthroscopic Bankart repair with a soft, all-suture anchor only occurred after return to competitive sports with new high-level trauma. LEVEL OF EVIDENCE: Level IV, retrospective cohort study.

Prediction of quadriceps tendon-patellar bone autograft diameter in adolescents with 2-dimensional magnetic resonance imaging and anthropometric measures.

OBJECTIVES: This study evaluates the correlation between the bone end and soft tissue end of the quadriceps tendon-patellar bone autograft (QPA) size and pre-operative MRI measurements of the quadriceps tendon along sections to be included in the graft harvest in adolescents. We also assessed association between graft diameter and anthropometric measures (height, weight, and BMI), age, and sex. METHODS: Patients (10-18 years) who underwent QPA ACL reconstruction and had a pre-operative MRI were considered for inclusion. Age, height, and weight, tibial and femoral side graft diameter, and patellar bone block dimensions were collected. Using a pre-operative 2D sagittal plane MRI, we measured the quadriceps at 10-mm increments above the patella, up to 40 mm. We assessed correlation between the bone-end graft diameter and the AP measure at 10 mm above the patella, and correlation between the soft-tissue end graft diameter and the most proximal AP measure. RESULTS: A total of 103 patients were included. A significant correlation between the soft-tissue side graft diameter and most proximal AP measurement was observed (rs = 0.51; p < 0.001). However, measurements significantly underestimated the soft-tissue end graft diameter (9.6 ± 0.8 vs. 7.4 ± 1.1; p < 0.001). There was no correlation between the bone-end graft diameter and AP measurement 10 mm above the patella. Anthropometric measures were not associated with graft size. Skeletal maturity was associated with smaller graft size (p = 0.08). CONCLUSION: Soft-tissue end graft diameter is associated with the AP measure of the quadriceps at 20-40 mm above the superior pole of the patella.

Friberg Equation to Predict Pediatric Distal Forearm Fracture Remodeling.

BACKGROUND: This study is the first to test Friberg's equation's (Vt=V0[e]) accuracy in predicting the residual angular deformity in pediatric distal forearm fractures. METHODS: Angular deformities from distal forearm fractures in 50 children (mean age, 9 y) were retrospectively measured on follow-up radiographs once healed and compared to extrapolated angles at respective follow-up intervals from 2013 to 2015. RESULTS: The predicted and actual angulations from 120 radiographs (mean follow-up, 3mo) showed that the mean predicted angle was similar to the measured angle in the radioulnar plane and only 2 degrees greater than the measured angle in the dorsovolar plane. A strong correlation was observed between predicted and measured angles in both planes. CONCLUSIONS: Friberg's equation is a valid tool for predicting remodeling potential in pediatric distal 25% forearm fractures. LEVEL OF EVIDENCE: Prognostic Study-Level II.

Synthetic temperature-inducible lethal gene circuits in Escherichia coli.

Temperature sensitivity is often used as a way to attenuate micro-organisms to convert them into live vaccines. In this work, we explore the use of temperature-sensitive (TS) genetic circuits that express lethal genes as a widely applicable approach to TS attenuation. We tested different combinations of TS repressors and cognate promoters controlling the expression of genes encoding restriction endonucleases inserted at four different non-essential sites in the Escherichia coli chromosome. We found that the presence of the restriction endonuclease genes did not affect the viability of the host strains at the permissive temperature, but that expression of the genes at elevated temperatures killed the strains to varying extents. The chromosomal insertion site of the lethal cassettes affected their functionality, and insertion at one site, ycgH, rendered them ineffective at inducing death at high temperature. Induction of a TS circuit in a growing culture led to a reduced cell mass and a reduction of the number of cells that could exclude a dye that indicated viability. Incubation of cells carrying a TS lethal gene circuit initially grown at low temperature and then suspended in phosphate buffered saline at high temperature led to about 100-fold loss of cell viability per day, compared to a minimal loss of viability for the parental strain. Strains carrying either one or two TS lethal circuits could generate mutants that survived at high temperature. These mutants included complete deletions of the lethal gene circuits.

Temperature-Sensitive Salmonella enterica Serovar Enteritidis PT13a Expressing Essential Proteins of Psychrophilic Bacteria.

Synthetic genes based on deduced amino acid sequences of the NAD-dependent DNA ligase (ligA) and CTP synthetase (pyrG) of psychrophilic bacteria were substituted for their native homologues in the genome of Salmonella enterica serovar Enteritidis phage type 13a (PT13a). The resulting strains were rendered temperature sensitive (TS) and did not revert to temperature resistance at a detectable level. At permissive temperatures, TS strains grew like the parental strain in broth medium and in macrophage-like cells, but their growth was slowed or stopped when they were shifted to a restrictive temperature. When injected into BALB/c mice at the base of the tail, representing a cool site of the body, the strains with restrictive temperatures of 37, 38.5, and 39°C persisted for less than 1 day, 4 to 7 days, and 20 to 28 days, respectively. The wild-type strain persisted at the site of inoculation for at least 28 days. The wild-type strain, but not the TS strains, was also found in spleen-plus-liver homogenates within 1 day of inoculation of the tail and was detectable in these organs for at least 28 days. Intramuscular vaccination of White Leghorn chickens with the PT13a strain carrying the psychrophilic pyrG gene provided some protection against colonization of the reproductive tract and induced an anti-S. enterica antibody response.

High healing rate of stable femoral condyle osteochondritis dissecans in young patients placed in a hinged knee brace locked in extension: a retrospective study.

We report the rate of stable femoral condyle osteochondritis dissecans (OCD) lesion healing in adolescents using a locked hinged knee brace for a minimum of 6 weeks or until pain free, followed by physical therapy. Patients aged 5-18 at the time of a primary diagnosis of femoral condyle OCD were reviewed. Patients who presented with an unstable lesion necessitating surgery, lacked follow-up >6 months after diagnosis or before symptoms resolution, or were noncompliant were excluded. We assessed progression to surgery, association between surgery and lesion size, lesion grade, symptoms, laterality, and patient factors. Lesion width and depth and condyle size were measured on X-ray and MRI, and the scaled size of the lesion relative to the condyle was calculated. Sixty-four patients were included: 12.5% (n = 8; 50% female; mean age = 12.5 ± 1.0 years) progressed to surgery and 87.5% (n = 56; 20% female; mean age=11.5 ± 1.9 years) healed. No significant effects were identified between groups. The surgical group compared to the non-surgical group was braced for a similar amount of time (72.6 ± 51.4 vs. 54.9 ± 23.2 days; P = 0.09), presented initially with a similar lesion size (322.5 ± 298.7 vs. 211.2 ± 178.4 mm2; P = 0.14), and had a similar proportion of Grade 1 lesions (63% vs. 85%; P = 0.11). Female sex (P = 0.04) and longer time in the brace (P = 0.04) were associated with progression to surgery.

Biomechanical Analysis of Tibial Motion and ACL Graft Forces After ACLR With and Without LET at Varying Tibial Slopes.

BACKGROUND: Lateral extra-articular tenodesis (LET) is being performed more frequently with anterior cruciate ligament (ACL) reconstruction (ACLR) to decrease graft failure rates. The posterior tibial slope (PTS) affects ACL graft failure rates. The effect of ACLR + LET on tibial motion and graft forces with increasing PTS has not been elucidated. HYPOTHESIS: LET would decrease anterior tibial translation (ATT), tibial rotation, and ACL graft force versus ACLR alone with increasing tibial slope throughout knee range of motion. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve fresh-frozen cadaveric knees (mean donor age, 40.5 years; all female) were tested in 4 conditions (intact, ACL cut, ACLR, and ACLR + LET) with varying PTSs (5°, 10°, 15°, and 20°) at 3 flexion angles (0°, 30°, and 60°). Specimens were mounted to a load frame that applied a 500-N axial load with 1 N·m of internal rotation (IR) torque. The amount of tibial translation, IR, and graft force was measured. RESULTS: Increasing PTS revealed a linear and significant increase in graft force at all flexion angles. LET reduced graft force by 8.3% (-5.8 N) compared with ACLR alone at 30° of flexion. At the same position, slope reduction resulted in reduced graft force by 17% to 22% (-12.3 to -15.2 N) per 5° of slope correction, with a 46% (-40.7 N) reduction seen from 20° to 5° of slope correction. For ATT, ACLR returned tibial translation to preinjury levels, as did ACLR + LET at all flexion angles, except full extension, where ACLR + LET reduced ATT by 2.5 mm compared with the intact state (P = .019). CONCLUSION: Increased PTS was confirmed to increase graft forces linearly. Although ACLR + LET reduced graft force compared with ACLR alone, slope reduction had a larger effect across all testing conditions. No other clinically significant differences were noted between ACLR with versus without LET in regard to graft force, ATT, or IR. CLINICAL RELEVANCE: Many authors have proposed LET in the setting of ACLR, revision surgery, hyperlaxity, high-grade pivot shift, and elevated PTS, but the indications remain unclear. The biomechanical performance of ACLR + LET at varying PTSs may affect daily practice and provide clarity on these indications.

Surgeon-Administered Anterolateral Geniculate Nerve Block as an Adjunct to Regional Anesthetic for Pain Management Following Anterior Cruciate Ligament Reconstruction.

Regional anesthetic blockade of the adductor canal following anterior cruciate ligament reconstruction has gained popularity due to theoretical benefit of improved patient experience, decreased requirement for pain medication and maintained motor function. However, this block does not cover the anterior and lateral genicular innervation to the knee, which may lead to persistent pain postoperatively. The following Technical Note details the genicular nervous system and provides rationale and technique for performing a simple surgeon-administered regional anesthetic at the completion of anterior cruciate ligament reconstruction to address the anterior and lateral genicular nervous system.

Arthroscopic Subcoracoid Decompression, Coracoplasty, and Subscapularis Repair for Subscapularis Tears in the Setting of Subcoracoid Impingement.

Subscapularis tears have been found to occur in the setting of subcoracoid impingement and are related to the narrowing of the coracohumeral interval. The advancement of arthroscopic techniques has allowed for improved identification and treatment of this historically overlooked pathology. Challenges of arthroscopic subscapularis treatment include nearby neurovascular structures, tendon retraction, and adhesions, which are further complicated by diminished arthroscopic visualization, resulting from the concomitant subcoracoid impingement. The purpose of this Technical Note is to describe our preferred technique for arthroscopic management of subscapularis tears in the setting of subcoracoid impingement that is simple and reproducible, as well as cost-effective and efficient with limited additional morbidity to that of a standard diagnostic shoulder arthroscopy.

Distal Tibial Chondroblastoma With Intra-articular Penetration Treated With Gelatin Foam Sponge and Bone Grafting.

A 14-year-old boy presented with sharp left ankle pain for 1.5 years. Evaluation showed an irregular lytic lesion with surrounding sclerosis (diameter, 1.3×1.2×1.1 cm) in the central part of the distal tibial epiphysis, extending from the physis to the plafond with articular penetration. Treatment included intralesional curettage and bone grafting through a mid-anterior epiphyseal bone tunnel with fluoroscopic guidance and use of a gelatin foam sponge to help contain the bone graft within the epiphyseal cavity. Microscopic examination of the excised tissue was consistent with chondroblastoma. Ankle arthroscopy 11 months later showed that the tibial plafond articular surface was fully healed. Two years postoperatively, the patient was asymptomatic and had no recurrence. This case shows that intralesional curettage and bone grafting, with a gelatin foam sponge to prevent graft extrusion, may be used successfully in treating distal tibial epiphyseal chondroblastoma that penetrates the ankle joint. [Orthopedics. 2019; 42(4):e391-e394.].

Outcomes and Return to Sport After Ulnar Collateral Ligament Reconstruction in Adolescent Baseball Players.

BACKGROUND: The number of ulnar collateral ligament (UCL) reconstructions in adolescent athletes has increased over the past 2 decades. Clinical results in this population have not been well studied. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the outcomes and return to sport after UCL reconstruction in a large group of adolescent baseball players. We hypothesized that excellent clinical outcomes and high rates of return to sport would be observed in this population at a minimum 2-year follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We reviewed 140 adolescent (aged ≤19 years) baseball players who underwent UCL reconstruction with the American Sports Medicine Institute (ASMI) technique by a single surgeon. Medical records were reviewed for patient demographics, injury characteristics, operative details, and surgical complications. Patient-reported outcomes were assessed using the Conway scale, the Andrews-Timmerman (A-T) score, the Kerlan-Jobe Orthopaedic Clinic (KJOC) score, and a 0- to 100-point subjective scale for elbow function and satisfaction. Return to sporting activity was assessed using a custom-designed questionnaire. RESULTS: The mean age at the time of surgery was 18.0 years (range, 13-19 years), and the mean follow-up was 57.9 months (range, 32.4-115.4 months). Over half (60%) of patients were high school athletes. The mean duration of symptoms before surgery was 6.9 months (range, 0.5-60.0 months). Partial tears were identified in 57.9% of patients, and 41.3% of patients had preoperative ulnar nerve symptoms. Graft type included the ipsilateral palmaris in 77.1% of patients. Concomitant procedures were performed in 25% of patients. Outcomes on the Conway scale were "excellent" in 86.4% of patients. The mean A-T and KJOC scores were 97.3 ± 6.1 and 85.2 ± 14.6, respectively. Mean patient satisfaction was 94.4. Overall, 97.8% of patients reported returning to sport at a mean of 11.6 months (range, 5-24 months), and 89.9% of patients returned to sport at the same level of competition or higher. A total of 11.6% of patients went on to play professional baseball. CONCLUSION: UCL reconstruction with the ASMI technique is an effective surgical option in adolescents, with excellent outcome scores. At a minimum of 2-year follow-up, nearly 90% of patients returned to their preinjury level of sport.

Outcomes and Return to Sport After Revision Anterior Cruciate Ligament Reconstruction in Adolescent Athletes.

BACKGROUND: The number of adolescent anterior cruciate ligament (ACL) injuries is rising with increased participation in higher level athletics at earlier ages. With an increasing number of primary ACL reconstructions (ACLRs) comes a rise in the incidence of revision ACLRs. PURPOSE: To evaluate the clinical results of revision ACLR across a group of high-level adolescent athletes with at least 2-year follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective review of 21 adolescent athletes (age range, 10-19 years) who underwent revision ACLR with at least 2-year follow-up was conducted. Patient-reported outcome measures (PROMs) included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm knee scoring scale, Tegner activity level scale, and modified Cincinnati Knee Rating System. Return to sport (RTS) and overall patient satisfaction were also assessed. RESULTS: The mean age at the time of surgery was 16.5 years (range, 14-19 years), and the mean follow-up was 46.4 months (range, 24-97 months); 42.9% of patients were female, and 52.4% of patients participated in collision sports. The mean time to failure after primary ACLR was 13.1 ± 8.0 months, and the most common mechanism of failure was noncontact in at least 66.7% of cases. The revision graft type included bone-patellar tendon-bone (BPTB) in 71.4% of cases; 26.7% of BPTB grafts were from the contralateral extremity. Concomitant procedures were performed for intra-articular lesions in 71.4% of patients. The mean patient satisfaction rate was 95.3%. There were 3 cases of a graft reinjury at a mean of 25 months postoperatively. The mean PROM scores were as follows: IKDC, 87.5 ± 12.7; Tegner, 7.2 ± 2.0; Lysholm, 93.7 ± 9.8; and Cincinnati, 93.4 ± 10.0. Of those attempting to RTS, 68.4% of patients successfully returned at the same level of competition. Patients with a lateral compartment chondral injury were less likely to RTS (P < .05). Independent variables shown to have no significant relationship to PROMs or RTS included age, follow-up, sport classification, associated meniscal tears, revision graft size/type, and concomitant procedures. CONCLUSION: Revision ACLR can be an effective surgical option in adolescents participating in collision and contact sports, with good to excellent subjective outcome scores. At a minimum 2-year follow-up, a graft rupture after revision ACLR occurred in 14% of cases. Of the athletes attempting to RTS, 68.4% returned to their preinjury level of competition.