Krych, Aaron J.

Abstract Posterolateral corner injuries are complex injuries, and their therapeutic management varies from one individual to another. Biomechanical studies demonstrate that anatomic posterolateral corner reconstruction restores knee kinematics better than nonanatomic reconstruction. The purpose of this report is to describe an all‐arthroscopic procedure for anatomic posterolateral corner reconstruction. Technique Video video See video under supplementary data.

Abstract Arthroscopic assessment of posterior compartments of the knee and the posterior aspect of the proximal tibial and fibula is challenging because of the relative proximity of the neurovascular bundle. This Technical Note describes a reproducible arthroscopic surgical approach in a cadaveric model that aims to identify and expose the popliteus tendon, posterior fibular head, fibular collateral ligament popliteal fibular ligament, biceps femoris tendon, and peroneal nerve. Technique Video video See video under supplementary data.

Abstract Tears of the posterior medial meniscus root commonly result in extrusion of the meniscus and disruption of tibiofemoral contact mechanics. Transtibial pull‐through repair of the root often results in healing of the tear, but postoperative extrusion may persist. In this scenario, the meniscus is unlikely to be chondroprotective. Therefore, an additional centralization procedure is necessary to improve the extrusion. Biomechanical studies have demonstrated that centralization can improve meniscus mechanics and potentially reduce the risk of osteoarthritis. This Technical Note describes an arthroscopic technique for medial meniscus posterior root repair that combines transtibial pullout and centralization sutures. Technique Video video See video under supplementary data.

Purpose To report the annual incidence of anterior shoulder instability (ASI) diagnosis, injury severity, and surgical stabilization in a U.S. population. Methods An established U.S. geographic database was used to identify patients < 40 years old with diagnoses of ASI from 1994‐2016. Medical records were reviewed to obtain patient demographics, histories, imaging results, and surgical details. Age‐ and sex‐specific incidence rates were calculated and adjusted to the 2010 U.S. population. Poisson regression was performed to examine trends by timeline, sex and age. Results The study population consisted of 652 patients with ASI and a mean age of 21.5 years (range, 3.6‐39.5). Comparing 2015‐2016 to 1994‐1999, we found an increase in the number of dislocations (from 1.0‐1.9; P = 0.016) and total instability events (from 2.3‐3.4; P = 0.041) per patient prior to presentation to a physician. There was a trend in increased diagnosis of bony Bankart and/or Hill‐Sachs on MRI over time, with these lesions documented in 96% of patients undergoing MRI in 2015‐2018 compared to 52.9% in 1994‐1999 ( P < .001). The use of arthroscopic procedures increased and peaked in 2005‐2009 (90% of surgical cases performed). The proportion of open Latarjet procedures increased from 2010‐2014 (14%) and 2015‐2018 (31%). Conclusions The age‐ and sex‐ adjusted incidence of ASI diagnosis in a U.S. population from 1994‐2016 is comparable to that demonstrated in Canadian and European populations. This study demonstrates an increasing number of instability events prior to surgical evaluation, which may correlate with patients’ more commonly presenting with bone loss and requiring more aggressive surgical treatment or that ASI is being more frequently cared for and documented by present‐day orthopedic surgeons. Level of Evidence Level III, cross‐sectional study.

AbstractThe purpose of this study was to determine patient-reported outcomes, hardware removal rates, as well as conversion to arthroplasty at mid-term follow-up following high tibial osteotomy (HTO) with a modern polyetheretherketone (PEEK) system. All PEEK system-based HTOs performed at a single institution between January 2010 and January 2016 with a minimum of 2 years follow-up were reviewed. Rates of postoperative complications, hardware removal and conversion to arthroplasty were calculated. Patient-reported outcomes including visual analog pain scale (VAS), Tegner activity scale, Lysholm, Knee Injury and Osteoarthritis Outcome Score (KOOS), and 36-Item Short Form Survey (SF-36) were obtained. Forty-seven HTOs in 43 patients (mean age: 37.6 ± 10.8 years; 30 M, 13 F) were followed for a mean of 6.0 ± 1.5 years. A total of four postoperative complications occurred in three patients, resulting in an overall complication rate of 6.4%. Hardware removal occurred in three patients at a mean of 0.73 ± 0.53 years after surgery, with overall survival free of hardware removal of 96% (95% confidence interval [CI]: 85–99) at 1 year, 94% (95% CI: 82–98) at 2 years, and 94% (95% CI: 82–98) at 8 years. Conversion to arthroplasty occurred in three patients at a mean of 3.2 ± 1.0 years after surgery, with mean survival of 100% (95% CI: 94–100) at 1 year, 100% (95% CI: 94–100) at 2 years, and 93% (95% CI: 81–98) at 8 years. VAS at rest improved, from 3.1 ± 2.5 preoperatively to 1.1 ± 1.6 postoperatively (p < 0.001). Patients remained active, with a mean Tegner activity scale of 4.4 ± 1.4 at final follow-up and satisfactory Lysholm, KOOS, and SF-36 scores. At mid-term follow-up, medial opening-wedge HTO using a modern PEEK-based system was found to be safe, efficacious, and durable, with satisfactory outcome scores and a low rate of conversion to arthroplasty. PEEK-based implants were found to have low hardware removal rates of 6% at 5 years, which compares favorably to historic metal fixation. This is a Level III study.

Background: Femoroacetabular impingement (FAI) is a well-known cause of hip pain in adolescents and young adults. However, the incidence in the general population has not been clearly defined. Purpose: To (1) define the population-based incidence of diagnosis of FAI in patients with hip pain, (2) report the trends in diagnosis of FAI over time, and (3) determine the changes in the rate and type of surgical management over time. Study Design: Cohort study; Level of evidence, 3. Methods: A geographic database was used to identify patients who were 14 to 50 years old with hip pain between the years 2000 and 2016. Chart and radiographic review was performed to determine which patients had FAI. To be included, patients had to have a triad of clinical symptoms, physical examination signs, and imaging findings consistent with FAI. Medical records were reviewed to obtain demographic information, clinical history, physical examination findings, imaging details, and treatment details. Statistical analysis determined the overall age- and sex-adjusted annual incidence of FAI diagnosis and trends over time. Results: There were 1893 patients evaluated with hip pain, and 716 (38%; 813 hips) had diagnosed FAI. The mean ± SD age was 27.2 ± 8.4 years, and 67% were female. The incidence of FAI diagnosis was 54.4 per 100,000 person-years. Female patients had a higher incidence than male patients (73.2 vs 36.1 per 100,000 person-years; P < .01). Incidence of FAI diagnosis were higher from 2010 to 2016 (72.6 per 100,000 person-years; P < .01) as compared with 2005 to 2009 (45.3) and 2000 to 2004 (40.3). Hip arthroscopy, surgical hip dislocation, and periacetabular osteotomy utilization increased from the 2000-2004 to 2010-2016 periods, respectively: 1 (1%) to 160 (20%; P = .04), 2 (1%) to 37 (5%; P = .01), and 1 (1%) to 22 (3%; P = .58). Conclusion: The overall incidence of FAI diagnosis was 54.4 per 100,000 person-years, and it consistently increased between 2000 and 2016. Female patients had a higher incidence than male patients. The utilization of joint preservation operations, including hip arthroscopy, surgical hip dislocation, and anteverting periacetabular osteotomy, increased over time.

Background: The rate of osteoarthritis (OA) in patients with a history of previous anterior shoulder instability (ASI) varies within the literature, with the majority of studies investigating rates after surgical stabilization. ASI appears to lead to increased rates of OA, although risk factors for developing OA in cohorts treated nonoperatively and operatively are not well-defined. Purpose: To determine the incidence of clinically symptomatic OA and identify potential risk factors for the development of OA in patients younger than 40 years with a known history of ASI. Study Design: Case-control study; Level of evidence, 3. Methods: An established, geographically based database was used to identify patients in the United States who were younger than 40 years and were diagnosed with ASI between 1994 and 2014. Patient information, including demographic, imaging, and surgical details, was collected. Comparative analysis was performed between groups with and without OA at final follow-up as well as between patients who underwent surgical and nonsurgical management. Results: The study population consisted of 154 patients with a mean follow-up of 15.2 years (range, 5.1-29.8 years). The mean age at initial instability event was 20.9 years (95% CI, 19.9-22.0 years). Overall, 22.7% of patients developed clinically symptomatic glenohumeral OA. Multivariate analysis revealed that current or former smokers (odds ratio [OR], 4.3; 95% CI, 1.1-16.5; P = .030), hyperlaxity (OR, 10.1; 95% CI, 1.4-72.4; P = .020), laborer occupation (OR, 6.1; 95% CI, 1.02-36.1; P = .043), body mass index (BMI) (OR, 1.2; 95% CI, 1.03-1.3; P = .012), and age at initial instability (OR, 1.1; 95% CI, 1.02-1.2; P = .013) as potential independent risk factors when accounting for other demographic and clinical variables. Conclusion: In a US geographic population of patients younger than 40 years with ASI, approximately one-fourth of patients developed symptomatic OA at a mean follow-up of 15 years from their first instability event. When accounting for differences in patient demographic and clinical data, we noted a potentially increased risk for the development of OA in patients who are current or former smokers, have hyperlaxity, are laborers, have higher BMI, and have increased age at initial instability event. Smoking status, occupation, and BMI are modifiable factors that could potentially decrease risk for the development of symptomatic OA in these patients.

Background: Meniscus root tears are increasingly being recognized. Meniscal extrusion has previously been associated with medial root tears; however, the relationship between secondary meniscal restraints, such as the meniscotibial (MT) ligament, extrusion, and root tears has yet to be formally evaluated. Purpose: To better understand the association between MT ligament competence, medial meniscal extrusion, and medial meniscus posterior root tears (MMPRTs) as well as to determine the progression of meniscal extrusion over time. Study Design: Case series; Level of evidence, 4. Methods: Serial magnetic resonance imaging (MRI) scans were reviewed for patients who showed evidence of medial meniscal extrusion and MMPRTs on at least 1 of ≥2 available MRI scans. All patients were symptomatic at the time of diagnosis. All MRI scans were analyzed independently by 2 board-certified musculoskeletal radiologists. MT ligament disruption, medial meniscal extrusion, and MMPRTs were recorded for each MRI scan. The time between MRI scans, presence of insufficiency fractures, and Outerbridge classification for the medial femur and tibia were also evaluated. Results: Overall, 27 knees in 26 patients were included in this study, with a total of 63 MRI scans analyzed (21 knees with 2 MRI scans, 3 with 3 MRI scans, and 3 with 4 MRI scans). All patients demonstrated clear medial meniscal extrusion and MT ligament disruption before the subsequent development of MMPRTs ( P < .001). Mean extrusion at the time of initial MRI was 3.3 ± 1.1 mm and increased significantly to 5.5 ± 1.8 mm at the time of first imaging with an identified MMPRT ( P < .001). The mean time between initial MRI and the first identification of an MMPRT on later MRI was 1.7 ± 1.6 years. Conclusion: In a sample of 27 symptomatic knees with serial MRI scans both before and after an MMPRT diagnosis, all patients demonstrated MT ligament disruption and associated meniscal extrusion before the development of subsequent medial meniscus root tears. These findings suggest that MT ligament disruption and medial meniscal extrusion represent early and predisposing events contributing to MMPRTs. Therefore, this provides a possible explanation of why meniscal extrusion is not corrected with medial meniscus root repair.

Purpose To compare the (1) rates of complications and reoperations, (2) rate of anterior cruciate ligament (ACL) graft failure, and (3) patient‐reported outcomes (PROs) among patients after hamstring autograft ACL reconstruction (ACLR) with and without independent suture tape reinforcement at a minimum 2‐year clinical follow‐up. Methods We performed a 1:2 matched‐cohort comparison of patients who underwent hamstring autograft ACLR with and without independent suture tape reinforcement between July 2011 and July 2017. Patients were matched according to age, sex, body mass index, preinjury Tegner activity score, and concomitant meniscal injury. Medical records were reviewed for demographic characteristics, additional injuries, and concomitant procedures. PRO scores (including Tegner activity, Lysholm, and International Knee Documentation Committee scores) and physical examination findings were collected both preoperatively and at a minimum of 2 years postoperatively. Results Overall, 108 patients who underwent ACLR were included: 36 patients (mean age, 25.3 years; range, 13‐44 years) with independent suture tape reinforcement and 72 patients (mean age, 24.9 years; range, 13‐54 years) without suture tape reinforcement. Overall, 5 of 36 suture tape patients (14%) and 10 of 72 control patients (14%) underwent reoperations. At an average follow‐up of 26.1 months in the suture tape cohort and 31.3 months in the control cohort, 1 patient in the suture tape cohort and 4 patients in the control cohort experienced graft failure. There were no statistically significant differences between the suture tape and control groups regarding return‐to‐sport rate (89% and 88%, respectively), postoperative International Knee Documentation Committee score (94.4 and 93.8, respectively), and postoperative Lysholm score (95.6 and 94, respectively). There was a statistically significant difference between the suture tape and control groups in postoperative Tegner activity score, at 7.1 (95% confidence interval, 6.5‐7.6) and 6.4 (95% confidence interval, 6.2‐6.6), respectively ( P = .026). Conclusions ACLR with hamstring autograft and independent suture tape reinforcement was performed safely with low rates of complications, graft failure, and reoperations with similar PROs, function, and return‐to‐sport rates when compared with hamstring autograft ACLR without suture tape reinforcement at a minimum 2‐year follow‐up. Level of Evidence Level III, retrospective comparative study.

AbstractPurposeOvernight admission following anterior cruciate ligament reconstruction has implications on clinical outcomes as well as cost benefit, yet there are few validated risk calculators for reliable identification of appropriate candidates. The purpose of this study is to develop and validate a machine learning algorithm that can effectively identify patients requiring admission following elective anterior cruciate ligament (ACL) reconstruction. MethodsA retrospective review of a national surgical outcomes database was performed to identify patients who underwent elective ACL reconstruction from 2006 to 2018. Patients admitted overnight postoperatively were identified as those with length of stay of 1 or more days. Models were generated using random forest (RF), extreme gradient boosting (XGBoost), linear discriminant classifier (LDA), and adaptive boosting algorithms (AdaBoost), and an additional model was produced as a weighted ensemble of the four final algorithms.ResultsOverall, of the 4,709 patients included, 531 patients (11.3%) required at least one overnight stay following ACL reconstruction. The factors determined most important for identification of candidates for inpatient admission were operative time, anesthesia type, age, gender, and BMI. Smoking history, history of COPD, and history of coagulopathy were identified as less important variables. The following factors supported overnight admission: operative time > 200 min, age < 35.8 or > 53.5 years, male gender, BMI < 25 or > 31.2 kg/m2, positive smoking history, history of COPD and the presence of preoperative coagulopathy. The ensemble model achieved the best performance based on discrimination assessed via internal validation (AUC = 0.76), calibration, and decision curve analysis. The model was integrated into a web‐based open‐access application able to provide both predictions and explanations.ConclusionModifiable risk factors identified by the model such as increased BMI, operative time, anesthesia type, and comorbidities can help clinicians optimize preoperative status to prevent costs associated with unnecessary admissions. If externally validated in independent populations, this algorithm could use these inputs to guide preoperative screening and risk stratification to identify patients requiring overnight admission for observation following ACL reconstruction.Level of evidenceIV.