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Krych, Aaron J

0000-0003-3248-8007

Mayo Clinic

Department of Orthopedics and Sports Medicine, Mayo Clinic, Rochester, Minnesota, USA.

Citations 352

Does Anterior Cruciate Ligament Reconstruction Protect the Meniscus and Its Repair? A Systematic Review

Orthopaedic Journal of Sports Medicine | July 28, 2020 | Volume: 8 | Issue: 7 | Pages: No page available

10.1177/2325967120933895 | PMID 32782901

Background: Anterior cruciate ligament (ACL) tear and meniscal injury often co-occur. The protective effect of early ACL reconstruction (ACLR) on meniscal injury and its repair is not clear. Critical literature review can support or change clinical strategies and identify gaps in the available evidence. Purpose: To assess the protective effect of ACLR on the meniscus and provide clinical guidelines for managing ACL tears and subsequent meniscal injury. We aimed to answer the following questions: (1) Does ACLR protect the meniscus from subsequent injury? (2) Does early ACLR reduce secondary meniscal injury compared with delayed ACLR? (3) Does ACLR protect the repaired meniscus? Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was performed through use of MEDLINE and Embase electronic databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Search terms included ACL, reconstruction, and meniscus. Studies describing primary ACLR and nonoperative treatment in adult patients were included, as well as studies indicating timing of ACLR. The included articles were assessed individually for risk of bias through use of the modified Cochrane Risk of Bias and MINORS (Methodological Index for Nonrandomized Studies) tools. Results: One level 2 randomized controlled trial and several level 3 and 4 studies indicated a protective effect of ACLR on meniscal injury compared with nonoperative treatment. There was weak (level 3) evidence of the protective effect of early ACLR on the meniscus. Meniscal repair failure was less frequent in patients with ACL reconstruction than in patients with ACL deficiency (level 4). Conclusion: The evidence collected in this review suggests a protective effect of ACLR for subsequent meniscal injury (level 2 evidence). ACLR should be performed within 3 months of injury (level 3 evidence). Meniscal injury requiring surgical repair in the ACL-deficient knee should be treated with repair accompanied by ACLR (level 3 evidence). The paucity of level 2 studies prevents the formation of guidelines based on level 1 evidence. There is a strong clinical need for randomized or prospective trials to provide guidelines on timing of ACLR and meniscal repair.
Linear Discriminant Analysis Successfully Predicts Knee Injury Outcome From Biomechanical Variables

The American Journal of Sports Medicine | July 21, 2020 | Volume: 48 | Issue: 10 | Pages: 2447-2455

10.1177/0363546520939946 | PMID 32693617

Background: The most commonly damaged structures of the knee are the anterior cruciate ligament (ACL), medial collateral ligament (MCL), and menisci. Given that these injuries present as either isolated or concomitant, it follows that these events are driven by specific mechanics versus coincidence. This study was designed to investigate the multiplanar mechanisms and determine the important biomechanical and demographic factors that contribute to classification of the injury outcome. Hypothesis: Linear discriminant analysis (LDA) would accurately classify each injury type generated by the mechanical impact simulator based on biomechanical input variables (ie, ligament strain and knee kinetics). Study Design: Controlled laboratory study. Methods: In vivo kinetics and kinematics of 42 healthy, athletic participants were measured to determine stratification of injury risk (ie, low, medium, and high) in 3 degrees of knee forces/moments (knee abduction moment, anterior tibial shear, and internal tibial rotation). These stratified kinetic values were input into a cadaveric impact simulator to assess ligamentous strain and knee kinetics during a simulated landing task. Uniaxial and multiaxial load cells and implanted strain sensors were used to collect mechanical data for analysis. LDA was used to determine the ability to classify injury outcome by demographic and biomechanical input variables. Results: From LDA, a 5-factor model (Entropy R 2 = 0.26) demonstrated an area under the receiver operating characteristic curve (AUC) for all 5 injury outcomes (ACL, MCL, ACL+MCL, ACL+MCL+meniscus, ACL+meniscus) of 0.74 or higher, with “good” prediction for 4 of 5 injury classifications. A 10-factor model (Entropy R 2 = 0.66) improved the AUC to 0.86 or higher, with “excellent” prediction for 5 injury classifications. The 15-factor model (Entropy R 2 = 0.85), produced 94.1% accuracy with the AUC 0.98 or higher for all 5 injury classifications. Conclusion: Use of LDA accurately predicted the outcome of knee injury from kinetic data from cadaveric simulations with the use of a mechanical impact simulator at 25° of knee flexion. Thus, with clinically relevant kinetics, it is possible to determine clinical risk of injury and also the likely presentation of singular or concomitant knee injury. Clinical Relevance: LDA demonstrates that injury outcomes are largely characterized by specific mechanics that can distinguish ACL, MCL, and medial meniscal injury. Furthermore, as the mechanics of injury are better understood, improved interventional prehabilitation can be designed to reduce these injuries.
A Novel Scoring Instrument to Assess Donor Site Morbidity After Anterior Cruciate Ligament Reconstruction With a Patellar Tendon Autograft at 2-Year Follow-up Using Contemporary Graft-Harvesting Techniques

Orthopaedic Journal of Sports Medicine | June 12, 2020 | Volume: 8 | Issue: 6 | Pages: No page available

10.1177/2325967120925482 | PMID 32587874

Background: Donor site morbidity after anterior cruciate ligament (ACL) reconstruction with a bone–patellar tendon–bone (BTB) autograft is clinically significant, but evidence with contemporary techniques is lacking. Purpose: To (1) evaluate donor site morbidity at a single institution using modern techniques of BTB autograft harvest at 2-year follow-up, (2) develop a 10-question donor site morbidity instrument, and (3) compare this instrument against traditional outcome tools. Study Design: Case series; Level of evidence, 4. Methods: We analyzed the 2-year follow-up outcomes of 200 consecutive patients who underwent ACL reconstruction with a BTB autograft performed by 2 surgeons at a single institution. The surgical technique utilized modern and consistent BTB autograft harvest, including graft sizing, patellar tendon and peritenon closure, and patellar and tibial donor site bone grafting. There were 187 patients included, with 13 patients undergoing revision ACL reconstruction excluded. An original 10-question scoring instrument evaluating donor site morbidity was administered to each patient (score, 0-100) and compared against each patient’s International Knee Documentation Committee (IKDC) and Lysholm scores. Results: Overall, 13.9% of patients were noted to have anterior knee pain with activity at 2-year follow-up. Moreover, 3.7% of patients reported an inability to kneel on hard surfaces but had no problems on soft surfaces; 5.9% of patients reported mild discomfort but were able to kneel on all surfaces. Additionally, 75.4% of patients had a perfect (100/100) donor site morbidity score. The mean donor site morbidity score at 2-year follow-up was 98.3 ± 3.4. There was a very strong correlation between the IKDC and Lysholm scores but only a strong and moderate correlation when the donor site morbidity score was compared with the IKDC and Lysholm scores, respectively. Conclusion: Donor site morbidity after ACL reconstruction with a BTB autograft was less frequent than reported in the existing literature. Some patients developed anterior knee pain; therefore, an informed discussion is advised. IKDC and Lysholm scores may not capture donor site symptoms after surgery. The 10-question donor site morbidity instrument may provide a more accurate assessment.
Comparable clinical outcomes using knotless and knot‐tying anchors for arthroscopic capsulolabral repair in recurrent anterior glenohumeral instability at mean 5‐year follow‐up

Knee Surgery, Sports Traumatology, Arthroscopy | May 27, 2020 | Volume: 29 | Issue: 7 | Pages: 2077-2084

10.1007/s00167-020-06057-7 | PMID 32462270

AbstractPurposeTo compare rates of recurrent instability, revision surgery and functional outcomes following arthroscopic anterior capsulolabral repair for recurrent anterior instability using knot‐tying versus knotless suture anchor techniques.MethodsPatients who had undergone arthroscopic anterior labrum and capsular repair for recurrent anterior glenohumeral instability using knotless anchors were identified. Those with minimum 2‐year follow‐up were matched (1:2) to knot‐tying anchor repair patients. Rates of failure and recurrent instability were compared, as well as Visual Analog Scale (VAS), Single Assessment Numeric Evaluation (SANE), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), University of California Los Angeles (UCLA) and Rowe scores.ResultsOne hundred and two patients (89 males, 13 females) with a mean age of 24.3 ± 9.6 were included. Repair was performed with knotless anchors in 34 and knot‐tying anchors in 68 shoulders. At mean follow‐up of 4.8 ± 2.5 years, re‐dislocation rates between groups were not significantly different (knotless anchor: 9% versus knot‐tying group: 15%, n.s.), but the knot‐tying group showed a higher re‐subluxation rate (p = 0.039). 12 (18%) revisions were performed in the knot‐tying group at a mean 2.9 years after surgery and 1 (3%) revision in the knotless anchors group at 1.4 years (n.s.). There was no difference in mean VAS with use (1.3 ± 1.9 versus 0.8 ± 1.5, n.s.), SANE scores (91.8 ± 12.7 versus 92.0 ± 11.0, n.s.), QuickDASH scores (4.1 ± 5.5 versus 3.0 ± 6.5, n.s.), UCLA Shoulder Score (32.5 ± 3.6 versus 33.2 ± 3.1, n.s.), or Rowe scores (90.5 ± 18.5 versus 92.2 ± 16.6, n.s.) between knotless and knot‐tying groups, respectively. VAS at rest was higher in the knotless group (0.7 ± 1.5 vs 0.1 ± 0.4, p = 0.021).ConclusionsKnotless anchors demonstrated similar rates of re‐dislocation and revision surgery, and lower rates of recurrent subluxation, compared to knot‐tying anchors. Patients achieved good‐to‐excellent functional outcomes. This supports the efficacy of knotless anchors as an alternative to knot‐tying anchors for arthroscopic anterior labral repair of recurrent anterior shoulder dislocation.Level of evidenceIII.
Lateral Meniscal Oblique Radial Tears Are Common With ACL Injury: A Classification System Based on Arthroscopic Tear Patterns in 600 Consecutive Patients

Orthopaedic Journal of Sports Medicine | May 19, 2020 | Volume: 8 | Issue: 5 | Pages: No page available

10.1177/2325967120921737 | PMID 32490027

Background: Meniscal root tears and ramp lesions have been rigorously characterized in recent literature. However, one of the most common lateral meniscal injuries identified with an acute anterior cruciate ligament (ACL) disruption, a posterior horn lateral meniscal oblique radial tear (LMORT), has not been thoroughly described. Purpose: To determine the incidence of all meniscal tears and, more specifically, the incidence of posterior horn LMORTs in a multicenter cohort of consecutive, acute ACL reconstructions. Additionally, the authors aimed to develop a new classification system to help guide treatment of posterior horn LMORTs. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A multicenter retrospective cohort design was used to analyze 200 consecutive cases of acute ACL reconstruction from each of 3 different surgeons, for a total of 600 patients. The operative notes and intraoperative photos were analyzed to determine the incidence and laterality of all meniscal tears. A classification system based on tear characterization was then used to categorize tear patterns into similar groups. Results: A total of 396 (66%) of the 600 patients with acute ACL disruption had concomitant meniscal tears. Specifically, 187 (31%) had a lateral meniscal injury, 89 (15%) had a medial meniscal injury, and 122 (20%) had both medial and lateral meniscal injuries. The most common lateral meniscal tear was an LMORT; 71 (18%) patients with meniscal tears had a posterior horn LMORT. Overall, the incidence of ACL injury with a concomitant posterior horn LMORT was 12%. A classification was developed, which included type 1 tear (partial thickness <10 mm from the root attachment), type 2 tear (complete radial oblique tear that extended <10 mm from root), type 3 tear (incomplete LMORT that extended >10 mm from root), and type 4 tear (complete LMORT >10 mm from root). Conclusion: In 600 consecutive acute ACL reconstructions, the incidence of concomitant ACL injury with meniscal injury was 66%, and posterior horn LMORTs represented a large proportion of all meniscal tears (12%). A classification scheme was developed for posterior horn LMORTs to aid reporting and clinical decision making for these common tears.
The Cost of Outpatient Arthroscopic Rotator Cuff Repairs: Hospital Reimbursement Is on the Rise While Surgeon Payments Remain Unchanged

Arthroscopy | April 30, 2020 | Volume: 36 | Issue: 9 | Pages: 2354-2361

10.1016/j.arthro.2020.03.038 | PMID 32360915

Purpose To better understand the relative increases in rotator cuff charges and to analyze national and regional trends between hospital, anesthesiologist, and surgeon charges and reimbursements for contemporary rotator cuff repairs (RCRs) performed in the United States. Methods A representative Medicare sample was used to capture hospital, surgeon, and anesthesiologist charges and payments for outpatient RCR from 2005 to 2014. The charges and reimbursements were calculated using Current Procedural Terminology codes. Two ratios were calculated to compare surgeon and hospital charges and reimbursements. The charge multiplier (CM) is the ratio of hospital to surgeon charges, and the payment multiplier (PM) is the ratio of hospital to surgeon reimbursements. Trends were evaluated using national and regional charges, reimbursements, Charlson Comorbidity Index, CM, and PM. Results In total, 12,617 patients were included in this study. Between 2005 and 2014, hospital charges for RCR significantly increased from $4877 to $11,488 (136% increase; P < .0001), anesthesiologist charges increased from $1319 to $2169 (64% increase; P < .0001), and surgeon charges increased from $7528 to $9979 (33% increase; P < .0001). Reimbursements during the same period significantly increased from $3007 to $6696 (123% increase; P < .0001) for hospitals, from $203 to $239 (17% increase; P = .005) for anesthesiologists. Reimbursements for surgeons remained relatively unchanged (from $1821 to $1885, 3% increase; P = .116). Increases in national CM ( P = .003) and PM ( P < .0001) were both statistically significant. Charlson Comorbidity Index did not change significantly over the period ( P = .1178). Conclusions Although outpatient RCR charges increased significantly for hospitals, surgeons, and anesthesiologists, hospital reimbursements increased substantially relative to surgeon and anesthesiologist reimbursements despite stable patient complexity. In 2005, hospitals were reimbursed 65% more than surgeons. By 2014, hospitals were reimbursed 255% more than surgeons, indicating that hospitals disproportionally drove increases in charges and reimbursements over this period. Level of Evidence Level IV, economic analysis
A Multicenter Study of Radiographic Measures Predicting Failure of Arthroscopy in Borderline Hip Dysplasia: Beware of the Tönnis Angle

The American Journal of Sports Medicine | April 28, 2020 | Volume: 48 | Issue: 7 | Pages: 1608-1615

10.1177/0363546520914942 | PMID 32343594

Background: Hip arthroscopy has been previously demonstrated to be an effective treatment for adult mild hip dysplasia. There are many radiographic parameters used to classify hip dysplasia, but to date few studies have demonstrated which parameters are of most importance for predicting surgical outcomes. Purpose: To identify preoperative radiographic parameters that are associated with poor outcomes in the arthroscopic treatment of adult mild hip dysplasia. Study Design: Case-control study; Level of evidence, 3. Methods: Radiographic analysis was performed in patients with mild hip dysplasia who underwent arthroscopic surgery between 2009 and 2015. Preoperative radiographic measurements included lateral center edge angle, Tönnis angle, neck shaft angle, anterior center edge angle, alpha angle, femoral head extrusion index, and acetabular depth-to-width ratio. Failure was defined as failure to achieve the minimal clinically important difference (MCID) utilizing the modified Harris Hip Score or as the need for secondary operation. The equal variance t test was used to analyze radiographic parameters. Statistical significance was determined using a P value of .05. Results: A total of 373 hips underwent analysis with an average follow-up of 41 months (range, 24-102 months). Of these, 46 hips (12%) required secondary operation, and 95 (25%) failed to meet the MCID. The overall failure rate was 32.4%. There was no single measurement or combination thereof associated with failure to reach the MCID. Higher preoperative Tönnis angles were associated with secondary operation, with a mean of 6.7° (95% CI, 5.3°-8.1°) in the secondary operation group versus 4.8° (95% CI, 4.4°-5.3°) in the nonsecondary operation group ( P = .006). The odds ratio was 1.12 (95% CI, 1.0-1.2; P = .05) per degree increase in Tönnis angle for secondary operation. In patients with a Tönnis angle >10°, 84% required secondary operation. Conclusion: Higher Tönnis angles portend a higher risk for revision surgery. The probability of secondary operation was increased by a magnitude of 1.12 with each degree increase in the Tönnis angle. In patients with a Tönnis angle >10°, 84% required a secondary operation.
Is Labral Size Predictive of Failure With Repair in Hip Arthroscopy?

Arthroscopy | April 27, 2020 | Volume: 36 | Issue: 8 | Pages: 2147-2157

10.1016/j.arthro.2020.04.022 | PMID 32353623

Purpose To assess whether labral size is predictive of labral repair failure or shows an association with patient outcomes after hip arthroscopy. Methods We performed a retrospective chart review of patients who underwent arthroscopic hip labral repair. Labral size was measured in 4 quadrants with an arthroscopic probe. The average size across torn labral segments was assessed for failure as determined by the change in patient‐reported outcomes, the rate at which subjects achieved the minimal clinically important difference and patient acceptable symptomatic state, and the need for additional surgery. Outcomes were evaluated for any continuous correlation as well as significant differences between the middle 50% of labral sizes and classes of labral sizes derived from upper and lower quartile and decile ranges. Included hips were those from patients aged between 18 and 55 years with 2‐year postoperative follow‐up and lateral center‐edge angles between 25° and 40°. Results The study included 571 hips. Labral width did not show a significant difference between hips requiring revision and those not requiring revision ( P = .4054). No significant correlation was found between labral width and the change in the International Hip Outcome Tool 12 score ( R 2 = 0.05780), modified Harris Hip Score ( R 2 = 0.19826), or Nonarthritic Hip Score ( R 2 = 0.23543) from preoperatively to 2 years postoperatively. Hips with labral sizes in the upper decile of our cohort showed significantly decreased improvement in the International Hip Outcome Tool 12 score ( P = .0287) and Nonarthritic Hip Score ( P = .0490) compared with the middle 50% of labral sizes. No statistically significant difference was found in the rate at which the groups achieved the minimal clinically important difference or patient acceptable symptomatic state. Conclusions Hypertrophic labra in the largest 10th percentile showed lower postoperative outcome scores. However, no detectable clinical benefit was found in terms of patient‐perceived clinical difference or acceptable symptomatic state. For most patients, labral size does not appear to significantly alter patient outcomes or the need for arthroplasty. Level of Evidence Level IV, retrospective case series.
Spontaneous Osteonecrosis/Subchondral Insufficiency Fractures of the Knee

Journal of Bone and Joint Surgery | March 27, 2020 | Volume: 102 | Issue: 9 | Pages: 821-829

10.2106/jbjs.19.00381 | PMID 32379123

Background: Spontaneous osteonecrosis of the knee has recently been termed subchondral insufficiency fracture of the knee (SIFK) to appropriately recognize the etiology of mechanical overloading of the subchondral bone. The purpose of this study was to assess clinical outcomes of SIFK based on progression to surgical treatment and arthroplasty, and to evaluate the risk factors that increase the progression to arthroplasty. Methods: A retrospective review was performed on patients with a diagnosis of SIFK, as confirmed with use of magnetic resonance images (MRIs). Baseline and final radiographs were reviewed. Baseline MRIs were also reviewed for injury characteristics. Failure was defined as progression to surgical treatment or conversion to arthroplasty. Results: Two hundred twenty-three patients (71% female) with a mean age of 65.1 years were included. SIFK affected 154 femora (69%) and 123 tibiae (55%), with medial compartment involvement in 198 knees (89%); 74% of medial menisci had root or radial tears, with a mean extrusion of 3.6 mm. Varus malalignment was identified in 54 (69%) of 78 knees. Seventy-six (34%) of all patients progressed to surgical intervention at 2.7 years, and 66 (30%) underwent arthroplasty at 3.0 years. The rates of conversion to surgical intervention and arthroplasty increased to 47% (37 of 79; p = 0.04) and 37% (29 of 79; p = 0.09), respectively, in patients with >5 years of follow-up. The 10-year survival rate free of arthroplasty for patients with SIFK on the medial femoral condyle (p < 0.01), SIFK on the medial tibial plateau (p < 0.01), medial meniscal extrusion (p = 0.01), varus alignment (p = 0.02), and older age (per year older; p = 0.003) was significantly higher than the survival rates of those without each respective condition. Conclusions: Subchondral insufficiency fractures predominantly involve the medial compartment of the knee and commonly present with medial meniscal root and radial tears. Approximately one-third of patients progressed to total knee arthroplasty. Baseline arthritis, older age, location of the insufficiency fracture on both the medial femoral condyle and medial tibial plateau, meniscal extrusion, and varus malalignment were all associated with progression to arthroplasty. Level of Evidence: Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Synthetic Biphasic Scaffolds versus Microfracture for Articular Cartilage Defects of the Knee: A Retrospective Comparative Study

CARTILAGE | February 12, 2020 | Volume: 13 | Issue: 1_suppl | Pages: 1002S-1013S

10.1177/1947603520903418 | PMID 32046514

Objective The purpose of this study was to compare the results of a biphasic synthetic scaffold (TruFit, Smith & Nephew) to microfracture for the treatment of knee cartilage defects and identify patient- and lesion-specific factors that influence outcomes. Design Prospectively collected data from 132 patients (mean age, 41.8 years; 69% male) with isolated chondral or osteochondral femoral defects treated with biphasic synthetic scaffolds ( n = 66) or microfracture ( n = 66) were reviewed. Clinical outcomes were evaluated longitudinally over 5 years with the Short Form–36 (SF-36), Activities of Daily Living of the Knee Outcome Survey (KOS-ADL), International Knee Documentation Committee (IKDC), and Marx Activity Scale. Cartilage-sensitive magnetic resonance imaging (MRI) was performed to evaluate osseous integration and cartilage fill in a subgroup of patients. Multivariate regression analysis was used to identify predictors of clinical outcomes within the scaffold group. Results Both groups demonstrated clinically significant improvements in knee clinical scores over 5 years ( P < 0.01). There were no significant differences in KOS-ADL and IKDC scores between groups up to 5 years postoperatively. Marx activity level scores in the microfracture group declined over time, while significant improvements in activity level scores were observed in the scaffold group over 5 years ( P < 0.01). Good-quality tissue fill and cartilage isointensity were more often observed in the scaffold group compared with the microfracture group, particularly with longer time intervals. Increasing age, high body mass index, prior microfracture, and traumatic etiology were predictors for inferior outcomes in the scaffold group. Conclusions Activity level and MRI appearance following treatment of cartilage lesions with the biphasic synthetic scaffold were superior to microfracture over time in this nonrandomized, retrospective comparison.