Femoral Positioning of the Anterolateral Ligament Graft With and Without Ultrasound Location of the Lateral Epicondyle

Background: In anterior cruciate ligament (ACL) reconstruction with anterolateral ligament (ALL) reconstruction, precise positioning of the ALL graft on the femur and tibia is key to achieve rotational control. The lateral femoral epicondyle is often used as a reference point for positioning of the ALL graft and can be located by palpation or with ultrasound guidance. Purpose: To compare the ALL graft positioning on the femoral side between an ultrasound-guided technique and a palpation technique for the location of the lateral epicondyle. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 120 patients receiving a primary combined ACL and ALL reconstruction between June and December 2019 were included. The location of the lateral epicondyle was determined by palpation in the palpation group (n = 60) and with preoperative ultrasound guidance in the ultrasound group (n = 60). Groups were comparable in age, sex, body mass index (BMI), and operated side. The planned positioning of the femoral ALL graft was proximal and posterior to the lateral epicondyle. The effective positioning of the femoral ALL graft was evaluated on postoperative lateral radiographs. The primary outcome was location of the graft in a 10-mm quadrant posterior and proximal to the lateral epicondyle. Results were analyzed in 2 subgroups according to BMI. Results: All 60 anterolateral grafts (100%) in the ultrasound group were positioned in a 10-mm quadrant posterior and proximal to the lateral epicondyle, as opposed to 52 (87%) in the palpation group ( P = .006). Errors in graft positioning with palpation occurred in overweight patients (BMI >25) as well as nonoverweight patients ( P = .3). Conclusion: Femoral positioning of the ALL graft posterior and proximal to the lateral epicondyle is more reproducible with ultrasound guidance when compared with palpation alone, regardless of BMI.

Live imaging of avian embryos revealing a new head precursor map and the role for the anterior mesendoderm in brain development

ABSTRACTWe investigated the initial stages of head development using a new method to randomly label chicken epiblast cells with enhanced green fluorescent protein, and tracking the labeled cells. This analysis was combined with grafting mCherry-expressing quail nodes, or node-derived anterior mesendoderm (AME). These live imagings provided a new conception of the cellular mechanisms regulating brain and head ectoderm development. Virtually all anterior epiblast cells are bipotent for the development into the brain or head ectoderm. Their fate depends on the positioning after converging to the AME. When two AME tissues exist following the ectopic node graft, the epiblast cells converge to the two AME positions and develop into two brain tissues. The anterior epiblast cells bear gross regionalities that already correspond to the forebrain, midbrain, and hindbrain axial levels shortly after the node is formed. Therefore, brain portions that develop with the graft-derived AME are dependent on graft positioning.

An Arthroscopic “Inlay” Bristow Procedure With Suture Button Fixation for the Treatment of Recurrent Anterior Glenohumeral Instability: 3-Year Follow-up

Background: Coracoid graft positioning, fixation, and bone union are key factors affecting the clinical outcomes of Bristow and Latarjet procedures. We developed an arthroscopic “inlay” Bristow procedure based on the “mortise-tenon” joint structure concept using suture button fixation to achieve more stable fixation and better bone union of the graft. Purpose: To evaluate the positioning of the coracoid graft, bone union rate, and clinical outcomes of this arthroscopic inlay Bristow procedure with suture button fixation. Study Design: Case series; Level of evidence, 4. Methods: A total of 62 patients who received the arthroscopic inlay Bristow procedure with suture button fixation between June 2015 to June 2016 were eligible for inclusion, and 56 patients who met the inclusion criteria were enrolled in this study. Radiological assessment on 3-dimensional computed tomography scan was performed preoperatively, immediately after the operation, and postoperatively at 3 months, 6 months, 1 year, and the final follow-up. Pre- and postoperative clinical results were also assessed. Results: A total of 56 patients were included in this study. The mean ± SD follow-up time was 36.1 ± 3.7 months. Coracoid grafts (middle point) were positioned at 4 o’clock (range, 123.8°± 12.3°) in the sagittal view. In the axial view, 94.6% (53/56) of the graft positioning was measured as flush and 5.4% (3/56) as medial. Neither lateral nor too medial positioning was noted. The bone union rate was 96.4% at final follow-up. The mean visual analog scale score for pain during motion, American Shoulder and Elbow Surgeons score, and Rowe score all improved significantly after surgery—from 4.8 ± 2.6 to 1.1 ± 1.0, 69.2 ± 12.5 to 92.5 ± 7.0, and 33.5 ± 12.1 to 96.0 ± 4.9 at last follow-up, respectively. Almost all patients (98%; 55/56) returned to sports within 1 year after surgery at the same or higher level as compared with their preinjury performance. The mean subjective value for sports participation was 90.3% ± 7.1% (range, 70%-100%) as compared with the normal shoulder. The overall complication rate was 3.6%. No degenerative changes were noted in any patients. Conclusion: This study reported the first series of an inlay Bristow procedure with suture button fixation for recurrent shoulder dislocation, providing a satisfactory union rate and excellent graft positioning with a low complication rate. The mortise-tenon joint structure can provide excellent graft fixation and healing, while using suture button fixation instead of screw fixation could reduce osteolysis and complications related to hardware implantation.

Arthroscopic Anatomic Glenoid Reconstruction: Analysis of the Learning Curve

Background: Anatomic glenoid reconstruction involves the use of distal tibial allograft for bony augmentation of the glenoid surface. An all-arthroscopic approach was recently described to avoid damage to the subscapularis tendon and preserve the capsule and labrum. Purpose: To explore and compare change in surgical time between 2 proposed methods used for the treatment of anterior shoulder instability—arthroscopic anatomic glenoid reconstruction (AAGR) and arthroscopic Latarjet (AL)—over successive procedures. We also compared graft positioning on the anterior glenoid surface between the 2 methods. Study Design: Cohort study; Level of evidence, 3. Methods: This was a single-surgeon retrospective review of 54 cases of surgically treated recurrent anterior shoulder instability: 27 had AAGR with distal tibial allograft, while the other 27 had AL. AAGR with the distal tibial allograft was the primary choice for the treatment of anterior shoulder instability; however, AL was performed when tibial allograft was not available from the bone bank. Thus, there was an overlapping period for those 2 procedures. Procedure start and end times were recorded, and duration was calculated. Postoperative 3-dimensional computed tomography scans were reviewed, and graft position was judged to be in the lower third (desired position), middle third, or upper third of the anterior glenoid surface. To assess learning, these data were organized in chronological order of surgery, and each surgical cohort was divided into 3 chronological clusters of 9 patients each. Learning was assessed through change in operative time over successive clusters, change in variability of operative time among clusters, and change in graft positioning among clusters. Statistical analysis comprised a 2-tailed independent-sample t test and the Levene test for equality of variance. Results: Our study found that AAGR was significantly faster to perform than AL in the early ( P = .001), middle ( P = .001), and late ( P = .05) clusters of each cohort. Duration of surgery did not significantly improve across clusters within each cohort ( P = .15-.79). There were no significant changes in the variability of surgical time in the AAGR group ( P = .09) or the AL group ( P = .13). Desired positioning of the bone graft on the anterior glenoid surface (lower third) was identified more commonly in the AAGR cohort. Conclusion: AAGR is faster to learn and perform than AL for the treatment of recurrent anterior shoulder instability with significant glenoid bone loss. The current study found higher rates of desired graft positioning for AAGR clusters.