Contributions of the Abductor Muscles to Rotational and Distractive Stability of the Hip in a Biomechanical Cadaveric Model.

Background: The gluteus minimus (GMin) and gluteus medius (GMed) are important dynamic stabilizers of the hip, but quantitative data on their biomechanical roles in stabilizing the hip are currently lacking. Purpose: To (1) establish a reproducible biomechanical cadaveric model of the hip abductor complex and (2) characterize the effects of loading the GMin and GMed on extraneous femoral rotation and distraction. Study Design: Controlled laboratory study. Methods: A total of 10 hemipelvises were tested in 4 muscle loading states: (1) unloaded, (2) the GMin loaded, (3) the GMed loaded, and (4) both the GMin and GMed loaded. Muscle loads were applied via cables, pulleys, and weights attached to the tendons to replicate the anatomic lines of action. Specimens were tested under internal rotation; external rotation; and axial traction forces at 0°, 15°, 30°, 60°, and 90° of hip flexion. Results: When loaded together, the GMin and GMed reduced internal rotation motion at all hip flexion angles (P < .05) except 60° and reduced external rotation motion at all hip flexion angles (P < .05) except 0°. Likewise, when both the GMin and GMed were loaded, femoral distraction was decreased at all angles of hip flexion (P < .05). Conclusion: The results of this study demonstrated that the GMin and GMed provide stability against rotational torques and distractive forces and that the amount of contribution depends on the degree of hip flexion. Clinical Relevance: Improved understanding of the roles of the GMin and GMed in preventing rotational and distractive instability of the hip will better guide treatment of hip pathologies and optimize nonoperative and operative therapies.

Hip Arthroscopy Simulator Training With Immersive Virtual Reality Has Similar Effectiveness to Nonimmersive Virtual Reality.

PURPOSE: To (1) compare the efficacy of immersive virtual reality (iVR) to nonimmersive virtual reality (non-iVR) training in hip arthroscopy on procedural and knowledge-based skills acquisition and (2) evaluate the relative cost of each platform. METHODS: Fourteen orthopaedic surgery residents were randomized to simulation training utilizing an iVR Hip Arthroscopy Simulator (n = 7; PrecisionOS) or non-iVR simulator (n = 7; ArthroS Hip VR; VirtaMed). After training, performance was assessed on a cadaver by 4 expert hip arthroscopists through arthroscopic video review of a diagnostic hip arthroscopy. Performance was assessed using the Objective Structured Assessment of Technical Skills (OSATS) and Arthroscopic Surgery Skill Evaluation Tool (ASSET) scores. A cost analysis was performed using the transfer effectiveness ratio (TER) and a direct cost comparison of iVR to non-iVR. RESULTS: Demographic characteristics did not differ between treatment arms or by training level, hip arthroscopy experience, or prior simulator use. No significant differences were observed in OSATS and ASSET scores between iVR and non-iVR cohorts (OSATS: iVR 19.6 ± 4.4, non-iVR 21.0 ± 4.1, P = .55; ASSET: iVR 23.7 ± 4.5, non-iVR 25.8 ± 4.8, P = .43). The absolute TER was 0.06 and there was a 132-fold cost difference of iVR to non-iVR. CONCLUSIONS: Hip arthroscopy simulator training with iVR had similar performance results to non-iVR for technical skill and procedural knowledge acquisition after expert arthroscopic video assessment. The iVR platform had similar effectiveness in transfer of skill compared to non-iVR with a 132 times cost differential. CLINICAL RELEVANCE: Due to the accessibility, effectiveness, and relative affordability, iVR training may be beneficial in the future of safe arthroscopic hip training.

Arthroscopic Coracoid Transfer in the Lateral Decubitus Position is Safe and Effective at Short-Term Follow-Up.

Purpose: To report on operative and clinical outcomes in a series of shoulders treated with arthroscopic Latarjet performed in the lateral decubitus position. Methods: Patients with shoulders that underwent arthroscopic Latarjet in the lateral decubitus position were identified. Data were retrospectively collected, including patient demographics, operative times, intra- and postoperative complications, and clinical and functional outcomes. Descriptive statistics were performed. Results: Eighteen shoulders in 17 patients were included in the study with a mean follow-up of 14 ± 12.1 months (range, 4-39 months). The mean operative time for all procedures was 132.2 ± 18.0 minutes, and the mean operative time for the first half of the cohort was significantly longer than that of the second half (141.6 ± 14.2 minutes vs 122.8 ± 17.0 minutes, P = .02). There were no intraoperative complications, and no patients required a conversion to open surgery. One patient experienced a recurrent dislocation after a traumatic event but was able to be treated nonoperatively. Preoperative and postoperative patient-reported outcome measures (PROMs) were able to be collected on 8 of 18 patients (44.4%). Although all PROMs demonstrated improvements postoperatively, only the Single Assessment Numeric Evaluation score and American Shoulder and Elbow Surgeons Shoulder Index displayed a statistically significant increase (P < .05). Five of 8 (62.5%) shoulders demonstrated bony fusion on postoperative computed tomography scan. Of those eligible, 100% of patients returned to sport or felt that they could return if they wanted to. Conclusions: The arthroscopic Latarjet is an effective procedure for managing glenohumeral instability and can safely be performed in the lateral decubitus position. Level of Evidence: Level IV, therapeutic case series.

Patient Outcomes Are Not Improved by Platelet-Rich Plasma Injection Onto the Capsule at the Time of Closure During Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

Purpose: To determine the effect of platelet-rich plasma (PRP) injection onto the capsule at time of closure on outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement syndrome. Methods: Patients who underwent hip arthroscopy between January 2014 and December 2021 were retrospectively identified. The first cohort included patients who received PRP injection onto the capsule following capsular closure at the conclusion of the case. The second cohort did not receive PRP. Pain scores on a visual analog scale, Modified Harris Hip Scores, Single Assessment Numeric Evaluation (SANE), as well as Patient-Reported Outcomes Measurement Information System Physical Function scores were obtained preoperatively as well as at multiple time points postoperatively up to 2 years. Results: In total, 345 patients were included in the study, with 293 in the PRP cohort and 52 in the non-PRP cohort. There was no significance difference in age (P = .69), sex, or preoperative pain (P = .92) and patient-reported outcome scores between the 2 groups (modified Harris Hip Score, P = .38; Patient-Reported Outcomes Measurement Information System Physical Function, P = .48), except for preoperative SANE scores, which had a greater baseline in the PRP group (P < .001). Using both observed data as well as repeated measure analysis of variance model to estimate for missing data after baseline, we found there were no differences in visual analog scale pain scores nor patient-reported outcome scores at any time point. There was similarly no difference in change from baseline for SANE scores. There was no difference in rate of revision surgery between the 2 cohorts (P = .66). Conclusions: Based on the results of this study, intraoperative PRP injection onto the capsule at the time of capsular closure does not improve outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement syndrome. Level of Evidence: Level III, retrospective comparative study.

Microbial Colonization of Capsular Traction Sutures in Hip Arthroscopic Surgery.

Background: A common practice in hip arthroscopic surgery is the utilization of capsular traction sutures that can be incorporated into the capsular repair site at the end of the procedure, potentially seeding the hip joint with colonized suture material. Purpose: To investigate the rate of the microbial colonization of capsular traction sutures used during hip arthroscopic surgery and to identify patient-associated risk factors for this microbial colonization. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 50 consecutive patients who underwent hip arthroscopic surgery with a single surgeon were enrolled. There were 4 braided nonabsorbable sutures utilized for capsular traction during each hip arthroscopic procedure. These 4 traction sutures and 1 control suture were submitted for aerobic and nonaerobic cultures. Cultures were held for 21 days. Demographic information was collected, such as age, sex, and body mass index. All variables underwent bivariate analysis, and variables with a P value <.1 underwent further analysis in a multivariate logistic regression model. Results: One of 200 experimental traction sutures and 1 of 50 control sutures had a positive culture. Proteus mirabilis and Citrobacter koseri were isolated in both these positive experimental and control cultures from the same patient. Age and traction time were not significantly associated with positive cultures. The rate of microbial colonization was 0.5%. Conclusion: The rate of the microbial colonization of capsular traction sutures used in hip arthroscopic surgery was low, and no patient-associated risk factors were identified for microbial colonization. Capsular traction sutures used in hip arthroscopic surgery were not a significant potential source of microbial contamination. Based on these results, capsular traction sutures can be incorporated in capsular closure with a low risk of seeding the hip joint with microbial contaminants.

Femoral Head Vascularity After Arthroscopic Femoral Osteochondroplasty: An In Vivo Dynamic Contrast-Enhanced MRI Study.

Background: A serious concern with surgical procedures around the hip joint is iatrogenic injury of the arterial supply to the femoral head (FH) and consequent development of FH osteonecrosis. Cam-type morphology can extend to the posterosuperior area. Understanding the limit of the posterior superior extension of the femoral osteochondroplasty is paramount to avoid underresection and residual impingement while maintaining FH vascularity. Purpose/Hypothesis: The aim of this study was to quantify the impact of arthroscopic femoral osteochondroplasty on the FH vascular supply. It was hypothesized that keeping the superior extension of the resection zone anterior to the 12-o'clock position would maintain FH vascularity. Study Design: Case series; Level of evidence, 4. Methods: Ten adult patients undergoing arthroscopic femoroacetabular impingement (FAI) surgery were included in the study. Computed tomography (CT) scans were obtained before and after arthroscopic osteochondroplasty to define the extension of resection margins. To quantify FH vascularity, postoperative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was obtained at 2 time points: immediately after surgery and at the 3-month follow-up. Custom MRI analysis software was used to quantify perfusion. Results: CT scan analysis demonstrated that the superior resection margin was maintained anterior to the 12-o'clock position in half of the patients. The remining 5 patients had a mean posterior extension of 11.4° ± 7.5°. The immediate postoperative DCE-MRI revealed diminished venous outflow in the operative side but no difference in overall FH perfusion. At the 3-month follow-up DCE-MRI, there was no perfusion difference between the operative and nonoperative FHs. Conclusion: This study provides previously unreported quantitative MRI data on in vivo perfusion of the FH after the commonly performed arthroscopic femoral osteochondroplasty for the treatment of cam-type FAI. Maintaining resection margins anterior to the 12-o'clock position, or even 10° posteriorly, was not observed to impair perfusion to the FH.

Prevalence of femoroacetabular impingement in elite baseball players.

CAM-type femoroacetabular impingement continues to be an underrecognized cause of hip pain in elite athletes. Properties inherent to baseball such as throwing mechanics and hitting may enhance the risk of developing a cam deformity. Our goal is to gain an appreciation of the radiographic prevalence of cam deformities in elite baseball players. Prospective evaluation and radiographs of 80 elite baseball players were obtained during the 2016 preseason entrance examination. A sports medicine fellowship-trained orthopedic surgeon with experience treating hip disorders used standard radiographic measurements to assess for the radiographic presence of cam impingement. Radiographs with an alpha angle >55° on modified Dunn views were defined as cam positive. Of the 122 elite baseball players included in our analysis, 80 completed radiographic evaluation. Only 7.3% (9/122) of players reported hip pain and 1.6% (4/244) had a positive anterior impingement test. The prevalence of cam deformities in right and left hips were 54/80 (67.5%) and 40/80 (50.0%), respectively. The mean alpha angle for cam-positive right and left hips were 64.7 ± 6.9° and 64.9 ± 5.8°, respectively. Outfielders had the highest risk of right-sided cam morphology (Relative Risk (RR) = 1.6). Right hip cam deformities were significantly higher in right-handed pitchers compared with left-handed pitchers (P = 0.02); however, there was no significant difference in left hip cam deformities between left- and right-handed pitchers (P = 0.307). Our data suggest that elite baseball players have a significantly higher prevalence of radiographic cam impingement than the general population.

Comparable Torque to Failure Using the Simple Stich Versus the Figure-of-Eight Configuration for Hip Capsular Closure Following an Interportal Capsulotomy: A Cadaveric Study.

PURPOSE: To measure and compare the torque to failure and stiffness of the capsular repair construct consisting of four-suture simple stitches to a two-figure of eight stitches repair construct in external rotation following an interportal capsulotomy. METHODS: Six pairs of fresh-frozen cadaveric hemipelves were divided into two capsular repair groups. All hips underwent a 40-mm interportal capsulotomy from the 12 o'clock position to the 3 o'clock position. Capsular closure was performed using either the two stitches in a figure of eight or with four simple stitches. Afterward, each hemipelvis was securely fixed to the frame of a mechanical testing system with the hip in 10° of extension and externally rotated to failure. Significance was set at P < .05. RESULTS: The average failure torque was 86.2 ± 18.9 N·m and 81.5 ± 8.9 N·m (P = .57) for the two stitches in a figure of eight and the four simple stitches, respectively. Failure stiffness was also not statistically different between groups and both capsular closure techniques failed at similar degrees of rotation (P = .65). CONCLUSION: Hip capsular repair using either the four simple stitch or two-figure of eight configurations following interportal capsulotomy demonstrated comparable failure torques and similar stiffness in a cadaveric model. CLINICAL RELEVANCE: Adequate and comprehensive capsular management in hip arthroscopy is critical. Capsular repair following capsulotomy in femoroacetabular impingement surgery has been associated with higher patient-reported outcomes when compared to capsulotomy without repair. Therefore, determining which capsular closure construct provides the higher failure torque is important.

An Increased Allograft Width for Circumferential Labral Reconstruction Better Restores Distractive Stability of the Hip: A Cadaveric Biomechanical Analysis.

BACKGROUND: Questions remain about whether circumferential labral reconstruction (CLR) using an iliotibial band (ITB) allograft can effectively restore the labral suction seal of the hip. HYPOTHESES: (1) CLR with an ITB allograft >6.5 mm would restore distractive stability force to that of the intact labrum. (2) CLR with an ITB allograft >6.5 mm would achieve significantly superior distractive stability force compared with CLR with an ITB allograft <6.5 mm. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 6 fresh-frozen pelves with attached femurs (n = 12 matched hemipelves) from male donors were procured and dissected free of all soft tissue, including the hip capsule but preserving the native labrum, transverse acetabular ligament, and ligamentum teres. Potted hemipelves were placed in a saline bath and securely fixed to the frame of a hydraulic testing system. A 500-N compressive load was applied, followed by femoral distraction at a rate of 5.0 mm/s until the suction seal ruptured. Force and femoral displacement were continually recorded. Force versus displacement curves were plotted, the maximum force was recorded, and the amount of femoral distraction to rupture the suction seal was determined. After intact testing, the labrum was excised, and specimens were retested using the same protocol. CLR was subsequently performed twice in a randomized fashion using (1) an ITB allograft with a width >6.5 mm (7.5-9.0 mm) and (2) an ITB allograft with a width <6.5 mm (4.5-6.0 mm). Specimens were retested after each CLR procedure. Force (in Newtons) and femoral distraction (in millimeters) required to rupture the suction seal were measured and compared between the 4 testing states (intact, deficient, CLR <6.5 mm, and CLR >6.5 mm) using repeated-measures analysis of variance. RESULTS: On average, intact specimens required 148.4 ± 33.1 N of force to rupture the hip suction seal, which significantly decreased to 44.3 N in the deficient state (P < .001). CLR with ITB allografts <6.5 mm did not improve the maximum force (63 ± 62 N) from the deficient state (P = .42) and remained significantly lower than the intact state (P < .01). CLR with ITB allografts >6.5 mm recorded significantly greater force to rupture the suction seal (135.8 ± 44.6 N) compared with both the deficient and CLR <6.5 mm states (P < .01), with a mean force comparable with the intact labrum (P = .59). The amount of femoral distraction to rupture the suction seal demonstrated similar findings. CONCLUSION: In a cadaveric model, CLR using ITB allografts >6.5 mm restored the distractive force and distance to the suction seal rupture to values comparable with hips with an intact labrum. CLR using ITB allografts >6.5 mm outperformed CLR with ITB allografts <6.5 mm, demonstrated by a significantly higher force to rupture the suction seal and increased distraction before the rupture. CLINICAL RELEVANCE: The results of this cadaveric investigation suggest that using wider labral allografts during CLR will provide the distractive force required to rupture the suction seal and immediate postoperative stability of the hip, although further studies are required to determine if these results translate to improved clinical outcomes.

Calculating Intraoperative Fluid Deficit to Prevent Abdominal Compartment Syndrome in Hip Arthroscopy.

Abdominal compartment syndrome (ACS) is a rare but potentially fatal complication that can occur during hip arthroscopy. This usually occurs as a result of arthroscopic fluid passing into the retroperitoneal space through the psoas tunnel. From the retroperitoneal space, the fluid can then enter the intraperitoneal space through defects in the peritoneum. Previous studies have identified female sex, iliopsoas tenotomy, pump pressure, and operative time as potential risk factors for fluid extravasation. We present a method to measure intraoperative fluid deficit during hip arthroscopy to alert surgeons to possible ACS. Our proposed technique requires diligent intraoperative monitoring of fluid output through various suction devices, including suction canisters, puddle vacuums, and suction mats. The difference is then calculated from the fluid intake from the arthroscopic fluid bags. If the difference is greater than 1500 mL, then the anesthesiologist and circulating nurse are instructed to examine the abdomen for distension every 15 minutes. This, combined with other common symptoms such as hypotension and hypothermia, should alert the surgical team to the development of ACS. Despite limitations to this technique, this approach offers an objective method to calculate intra-abdominal fluid extravasation.

Arthroscopic Latarjet Procedure Utilizing a Latarjet With Cortical Button Fixation Performed in the Lateral Position.

Shoulder instability is a commonly seen pathology. The Latarjet procedure was first described in 1954 to address recurrent instability or patients with glenoid bone loss. Since its introduction, the procedure has been widely adopted and modified, including being performed all-arthroscopically. Various arthroscopic techniques have been described, but we present a technique performed in the lateral decubitus position that takes advantage of a pneumatic arm holder. After arthroscopic diagnosis, multiple accessory portals are established and used to accomplish the technique. Next, the coracoid is prepared and cut using a cannulated drill guide, followed by arthroscopic glenoid preparation using a cannulated drill system to ensure appropriate position of the coracoid. The subscapularis split is performed arthroscopically, and finally the coracoid is fixed with use of the EndoButton device.

All-Arthroscopic Anatomic Length-Tension Biceps Tenodesis With Unicortical Button.

The long head of the biceps tendon is a frequent cause of persistent anterior shoulder pain. Biceps tenodesis is a popular choice for surgical management of this pathology, with myriad approach and fixation variations described. We describe an all-arthroscopic suprapectoral biceps tenodesis in the anatomic length-tension relation using a unicortical button. This technique offers an alternative method that provides proper tendon fixation at anatomic length with minimized additional surgical morbidity and postoperative complications.

Proximal Overresection During Femoral Osteochondroplasty Negatively Affects the Distractive Stability of the Hip Joint: A Cadaver Study.

BACKGROUND: Contact between the acetabular labrum and articular cartilage of the femoral head creates a suction seal that helps maintain stability of the femoral head in the acetabulum. A femoral osteochodroplasty may occasionally extend proximally into the femoral head, diminishing the articular surface area available for sealing contact. PURPOSE: To determine whether proximal overresection decreases the rotational and distractive stability of the hip joint. STUDY DESIGN: Controlled laboratory study. METHODS: Six hemipelvises in the following conditions were tested: intact, T-capsulotomy, osteochondroplasty to the physeal scar, and 5- and 10-mm proximal extension. The pelvis was secured to a metal plate, and the femur was potted and attached to a multiaxial hip jig. Specimens were axially distracted using a load from 0 to 150 N. For rotational stability testing, 5 N·m of internal and external torque was applied. Both tests were performed at different angles of flexion (0°, 15°, 30°, 60°, 90°). Displacement and rotation were recorded using a 3-dimensional motion tracking system. RESULTS: The T-capsulotomy decreased the distractive stability of the hip joint. A femoral osteochondroplasty up to the physeal scar did not seem to affect the distractive stability. However, a proximal extension of the resection by 5 and 10 mm increased axial instability at every angle of flexion tested, with the greatest increase observed at larger angles of flexion (P < .01). External rotation increased significantly after T-capsulotomy in smaller angles of flexion (0°, P = .01; 15°, P = .01; 30°, P = .03). Femoral osteochondroplasty did not create further external rotational instability, except when the resection was extended 10 mm proximally and the hip was in 90° of flexion (P = .04). CONCLUSION: This cadaveric study demonstrated that proximal extension of osteochondroplasty into the femoral head compromises the distractive stability of the hip joint but does not affect hip rotational stability. CLINICAL RELEVANCE: Clinically, this study highlights the importance of accuracy when performing femoral osteochondroplasty to minimize proximal extension that may increase iatrogenic instability of the hip joint.

Does Capsular Closure Affect Clinical Outcomes in Hip Arthroscopy? A Prospective Randomized Controlled Trial.

BACKGROUND: There is increasing concern of iatrogenic hip instability after capsulotomy during surgery. Greater emphasis is now being placed on capsular closure during surgery. There are no prospective studies that address whether capsular closure has any effect on outcomes. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate patient outcomes after interportal capsulotomy repair compared with no repair. We hypothesized that restoration of normal capsular anatomy with interportal repair will achieve clinical outcomes similar to those for no repair. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Adult patients with femoral acetabular impingement indicated for hip arthroscopy were randomized into either the capsular repair (CR) or the no repair (NR) groups. All patients underwent standard hip arthroscopy with labral repair with or without CAM/pincer lesion resection. Clinical outcomes were measured via the Hip Outcome Score-Activities of Daily Living (HOS-ADL) subscale, Hip Outcome Score-Sport Specific (HOS-SS) subscale, modified Harris Hip Score (mHHS), visual analog scale for pain, International Hip Outcome Tool, and Veterans RAND 12-Item Health Survey (VR-12). RESULTS: A total of 54 patients (56 hips) were included (26 men and 30 women) with a mean age of 33 years. The HOS-ADL score significantly improved at 2 years in both the NR group (from 68.1 ± 20.5 to 88.6 ± 20.0; P < .001) and the CR group (from 59.2 ± 18.8 to 91.7 ± 12.3; P < .001). The HOS-SS score also significantly improved in both the NR group (from 41.1 ± 25.8 to 84.1 ± 21.9; P < .001) and the CR group (from 32.7 ± 23.7 to 77.7 ± 23.0; P < .001). Improvement was noted for all secondary outcome measures; however, there was no significant difference between the groups at any time point. Between 1 and 2 years, the NR group showed significant worsening on the HOS-ADL (-1.21 ± 5.09 vs 4.28 ± 7.91; P = .044), mHHS (1.08 ± 10.04 vs 10.12 ± 11.76; P = .042), and VR-12 Physical (-2.15 ± 5.52 vs 4.49 ± 7.30; P = .014) subsets compared with the CR group. CONCLUSION: There was significant improvement in the VR-12 Physical subscale at 2 years postoperatively in the capsular CR group compared with the NR group. Capsular closure appears to have no detrimental effect on functional outcome scores after hip arthroscopy. We recommend restoration of native anatomy if possible when performing hip arthroscopy.

Epidemiologic impact of COVID-19 on a multi-subspecialty orthopaedic practice.

The purpose of this study is to report the change in surgical case volume and composition encountered by a multi-subspecialty orthopaedic practice due to COVID-19. We reviewed electronic medical records for patients who had surgery at our institution and collected multiple variables including age and the joint that was operated on. In the post-COVID-19 period, we found a significant increase in the percentage of hip procedures, and a significant decrease in the percentage of hand/wrist procedures. Overall, the total surgical volume of our multi-subspecialty orthopaedic practice decreased due to the COVID-19 pandemic, and the composition of surgical cases changed.

Arthroscopic Hip Capsular Plication With Augmentation Using a Bioinductive Collagen Implant.

With advancements in arthroscopic techniques and instrumentation, hip arthroscopy has become an increasingly used technique to treat soft-tissue and osseous pathologies about the hip. Patient predisposition to labral and capsular injuries can present as femoroacetabular impingement or hip dysplasia, sometimes in combination. Capsular management continues to be a topic of debate, with capsular repair becoming the standard of care in most cases. Furthermore, in cases of borderline dysplasia and microinstability, considerations for not only capsular repair but with plication has shown significant clinical success. Although plication in this setting has shown promise, given a 20% failure rate, we suggest capsular augmentation to bolster the repair. We present a technique of capsular augmentation using a bioinductive collagen implant (Smith & Nephew) to improve the capsular integrity following repair and plication. The benefits of this implant are easy delivery through standard arthroscopic portals and secure fixation to the capsular tissue. These implants have a proven track record in the shoulder and serve as a scaffold for improved tissue quality, and their application in hip arthroscopy has potential by increasing the integrity of the capsular repair. Future studies are needed to address the clinical outcomes of this technique.

Biomechanical evaluation of PCL reconstruction with suture augmentation.

PURPOSE: The purpose of this study was to compare kinematics and patellofemoral contact pressures of all inside and transtibial single bundle PCL reconstructions and determine if suture augmentation further improves the biomechanics of either technique. METHODS: Cadaveric knees were tested with a posterior drawer force, and varus, valgus, internal and external moments at 30, 60, 90, and 120° of flexion. Displacement, rotation, and patellofemoral contact pressures were compared between: Intact, PCL-deficient, All-Inside PCL reconstruction with (AI-SA) and without (AI) suture augmentation, and transtibial PCL reconstruction with (TT-SA) and without (TT) suture augmentation. RESULTS: Sectioning the PCL increased posterior tibial translation (PTT) from intact at 60° to 120° of flexion, p < 0.001. AI PCL reconstruction improved stability from the deficient-state but had greater PTT than intact at 90° of flexion, p < 0.05. Adding suture augmentation to the AI reconstruction further reduced PTT to levels that were not statistically different from intact at all flexion angles. TT reconstructed knees had greater PTT than intact knees at 60, 90, and 120° of flexion, p < 0.01. Adding suture augmentation (TT-SA) improved posterior stability to PTT levels that were not statistically different from intact knees at 30, 60, and 120° of flexion. Patellofemoral pressures were highest in PCL-deficient knees at increased angles of flexion and were reduced after reconstruction, but this was not significant. CONCLUSION: In this time-zero study, both the all-inside and transtibial single bundle PCL reconstructions effectively reduce posterior translation from the deficient-PCL state. In addition, suture augmentation of both techniques provided further anterior-posterior stability.

Anatomic and Biomechanical Evaluation of Ulnar Tunnel Position in Medial Ulnar Collateral Ligament Reconstruction.

BACKGROUND: Although numerous techniques of reconstruction of the medial ulnar collateral ligament (mUCL) have been described, limited evidence exists on the biomechanical implication of changing the ulnar tunnel position despite the fact that more recent literature has clarified that the ulnar footprint extends more distally than was appreciated in the past. PURPOSE: To evaluate the size and location of the native ulnar footprint and assess valgus stability of the medial elbow after UCL reconstruction at 3 ulnar tunnel locations. STUDY DESIGN: Controlled laboratory study. METHODS: Eighteen fresh-frozen cadaveric elbows were dissected to expose the mUCL. The anatomic footprint of the ulnar attachment of the mUCL was measured with a digitizing probe. The area of the ulnar footprint and midpoint relative to the joint line were determined. Medial elbow stability was tested with the mUCL in an intact, deficient, and reconstructed state after the docking technique, with ulnar tunnels placed at 5, 10, or 15 mm from the ulnotrochlear joint line. A 3-N·m valgus torque was applied to the elbow, and valgus rotation of the ulna was recorded via motion-tracking cameras as the elbow was cycled through a full range of motion. After kinematic testing, specimens were loaded to failure at 70° of elbow flexion. RESULTS: The mean ± SD length of the mUCL ulnar footprint was 27.4 ± 3.3 mm. The midpoint of the anatomic footprint was located between the 10- and 15-mm tunnels across all specimens at a mean 13.6 mm from the joint line. Sectioning of the mUCL increased elbow valgus rotation throughout all flexion angles and was statistically significant from 30° to 100° of flexion as compared with the intact elbow (P < .05). mUCL reconstruction at all 3 tunnel locations restored stability to near intact levels with no significant differences among the 3 ulnar tunnel locations at any flexion angle. CONCLUSION: Positioning the ulnar graft fixation site up to 15 mm from the ulnotrochlear joint line does not significantly increase valgus rotation in the elbow. CLINICAL RELEVANCE: A more distal ulnar tunnel may be a viable option to accommodate individual variation in morphology of the proximal ulna or in a revision setting.

Predictors of Clinical Outcomes After Proximal Hamstring Repair.

BACKGROUND: Proximal hamstring avulsions cause considerable morbidity. Operative repair results in improved pain, function, and patient satisfaction; however, outcomes remain variable. PURPOSE: To evaluate the predictors of clinical outcomes after proximal hamstring repair. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We retrospectively reviewed proximal hamstring avulsions repaired between January 2014 and June 2017 with at least 1-year follow-up. Independent variables included patient demographics, medical comorbidities, tear characteristics, and repair technique. Primary outcome measures were the Single Assessment Numerical Evaluation (SANE), International Hip Outcome Tool-12 (iHOT-12), and Kerlan-Jobe Orthopaedic Clinic (KJOC) Athletic Hip score. Secondary outcome measures included satisfaction, visual analog scale for pain, Tegner score, and timing of return to sports. RESULTS: Of 102 proximal hamstring repairs, 86 were eligible, 58 were enrolled and analyzed (67%), and patient-reported outcomes were available for 45 (52%), with a mean 29-month follow-up. The mean patient age was 51 years, and 57% were female. Acute tears accounted for 66%; 78% were complete avulsions. Open repair was performed on 90%. Overall satisfaction was 94%, although runners were less satisfied compared with other athletes (P = .029). A majority of patients (88%) returned to sports by 7.6 months, on average, with 72% returning at the same level. Runners returned at 6.3 months, on average, but to the same level 50% of the time and at a decreased number of miles per week compared to nonrunners (15.7 vs 7.8, respectively; P < .001). Postoperatively, 78% had good/excellent SANE Activity scores, but the mean Tegner score decreased (from 5.5 to 5.1). Acute tears had higher SANE Activity scores. The mean iHOT-12 and KJOC scores were 99 and 77, respectively. Endoscopic repairs had equivalent outcome scores to open repairs, although conclusions were limited given the small number of patients in the endoscopic group. Greater satisfaction was noted in patients older than 50 years (P = .024), although they were less likely to return to running (P = .010). CONCLUSION: Overall, patient satisfaction and functionality were high. With the numbers available, we were unable to detect any significant differences in functional outcome scores based on patient age, sex, body mass index, smoking status, medical comorbidities, tear grade, activity level, or open versus endoscopic technique. Acute tears had better SANE Activity scores. Runners should be cautioned that they may be unable to return to the same preinjury activity level after proximal hamstring repair. CLINICAL RELEVANCE: When counseling patients with proximal hamstring tears, runners and those with chronic tears should set appropriate expectations.

Posterior capsule injection of local anesthetic for post-operative pain control after ACL reconstruction: a prospective, randomized trial.

PURPOSE: Alternative modalities to optimize pain control after anterior cruciate ligament reconstruction (ACLR) are continually being explored. The purpose of this study was to compare femoral nerve block (FNB) only vs FNB with posterior capsule injection (PCI) of the knee for pain control in patients undergoing ACLR. METHODS: Patients undergoing primary ACLR were randomized to receive either FNB only or FNB with PCI. Following surgery, patient's pain was evaluated in the postoperative care unit (PACU) and at home for 4 days. Pain levels were measured via visual analog scale (VAS) and calculating opioid consumption. Outcomes of interest included postoperative pain levels and opioid consumption. RESULTS: A total of 42 patients were evaluated, with 21 patients randomized to each study arm. Outcomes showed significant pain reduction in both anterior and posterior knee VAS scores in the PACU in those that received PCI (anterior VAS: 39.6 vs 21.3 (SD = 12.9), p < 0.01; posterior VAS: 25.4 vs 15.3 (SD = 8.05), p = 0.01). Moreover, the PCI group also showed significantly less opioid consumption compared to FNB only (23.5 vs 17.4 pills, p = 0.03). There were no differences found in pain scores between groups in home VAS sores. CONCLUSIONS: These finding suggest the use of arthroscopically assisted injection of local anesthetic to the posterior capsule of the knee significantly reduces early post-operative pain and dramatically reduces the number of opoid medication taken after ACLR. LEVEL OF EVIDENCE: Prospective, randomized, control trial, Level I.