Back to Authors

Krych, Aaron J

0000-0003-3248-8007

Mayo Clinic

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

Citations 352

Systematic Review of Medial Patellofemoral Ligament Reconstruction Techniques: Comparison of Patellar Bone Socket and Cortical Surface Fixation Techniques

Arthroscopy | April 15, 2019 | Volume: 35 | Issue: 5 | Pages: 1618-1628

10.1016/j.arthro.2018.10.150 | PMID 31000392

Purpose To compare patellar bone socket and cortical surface fixation techniques for isolated medial patellofemoral ligament (MPFL) reconstruction and determine whether there was a difference in (1) complication rates, including fracture of the patella; (2) redislocation rates; or (3) patient‐reported outcomes. Methods A literature search was conducted following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. We included patients who underwent isolated MPFL reconstruction for recurrent patellar instability. Patients with confirmed concomitant or prior ipsilateral knee procedures, multiligament injury, or less than 3 months of follow‐up were excluded. Risk‐of‐bias assessment was performed using the Methodological Index for Non‐randomized Studies (MINORS) system. Studies were classified by surgical technique (patellar bone socket group [group S] vs cortical fixation group [group F]), and complications, redislocations, and patient‐reported outcomes were collected. Results A total of 29 studies yielded 981 patients with MPFL reconstruction for inclusion. Of the patients, 620 underwent a patellar bone socket technique and 361 underwent a cortical fixation technique. Patients ranged in age from 11 to 68 years. Patellar fracture rates ranged from 0% to 17% in group S and were 0% in all group F studies. Mean Kujala scores ranged from 83.5 to 93.6 in group S and from 84.4 to 94.5 in group F. Mean Lysholm scores ranged from 84.6 to 91.7 in group S and from 83.5 to 95 in group F. Redislocation rates ranged from 0% to 21% in group S and from 0% to 13% in group F. Although heterogeneous in nature, complication rates ranged from 0% to 28% in group S and from 0% to 4% in group F. Conclusions MPFL reconstruction techniques with patellar bone sockets showed a larger range of complication rates than cortical fixation techniques, although overall, complications remained uncommon. Clinically, the bone socket group had comparable postoperative redislocation rates and patient outcomes to the group treated with cortical fixation techniques. Level of Evidence Level IV, systematic review of Level I through IV studies.
Knee Abduction and Internal Rotation Moments Increase ACL Force During Landing Through the Posterior Slope of the Tibia

Journal of Orthopaedic Research | April 12, 2019 | Volume: 37 | Issue: 8 | Pages: 1730-1742

10.1002/jor.24313 | PMID 30977558

ABSTRACTThe mechanism underlying non‐contact anterior cruciate ligament (ACL) injury is multi‐factorial and still an object of debate. Computational models, in combination with in vivo and cadaveric studies, can provide valuable insight into the contribution of the different factors involved. The goal of this study was to validate four knee finite element models (two males and two females) to kinematic and strain data collected in vitro with an impact‐driven simulator and use them to assess how secondary external knee loads (knee abduction moment [KAM], anterior shear force, and internal rotation torque [ITR]) affect tibiofemoral contact forces and ACL force during impact. Four subject‐specific knee models were developed from specimen computed tomography and magnetic resonance imaging. Patellofemoral and tibiofemoral ligament properties were calibrated to match experimentally measured kinematics and ligament strain. Average root mean square errors and correlations between experimental and model‐predicted knee kinematics were below 1.5 mm and 2°, and above 0.75, respectively. Similar errors and correlations were obtained for ACL strain (< 2% and > 0.9). Model‐predicted ACL forces were highly correlated with the anterior component of the tibiofemoral contact force on the lateral plateau occurring during impact (r = 0.99), which was increased by larger KAM and ITR through the posterior tibial slope and a larger contact force on the lateral side. This study provides a better understanding of the mechanism through which secondary external knee loads increase ACL injury risk during landing. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1730–1742, 2019
Bilateral Hip Arthroscopy: Can Results From Initial Arthroscopy for Femoroacetabular Impingement Predict Future Contralateral Results?

Arthroscopy | April 9, 2019 | Volume: 35 | Issue: 6 | Pages: 1837-1844

10.1016/j.arthro.2018.12.033 | PMID 30979623

Purpose To determine the degree of correlation of radiographic measurements, degree of correlation of intraoperative pathology, and difference in outcomes between sides of patients requiring staged bilateral hip arthroscopy. Methods Two high‐volume hip preservation centers retrospectively reviewed hip preservation databases for staged bilateral hip arthroscopies conducted between 2008 and 2015. Patients were separated into those who presented with bilateral hip pain and those that presented with unilateral pain and developed contralateral pain >2 years later. Patients were analyzed for radiographic correlation (alpha angle, lateral center edge angle, anterior center edge angle, magnetic resonance imaging alpha angle, Tönnis grade) and correlation of intraoperative pathology (acetabular labrum articular disruption grade, Outerbridge grade/location, Villar class ligamentum teres tears, labral tear location, symmetry of Seldes tear types, and the differences between operative procedures). Patient‐reported outcomes were analyzed (modified Harris Hip Score, Non‐Arthritic Hip Score, International Hip Outcome Tool‐12, hip outcome score‐sport specific subscale, visual analog scale, patient satisfaction). Correlative tests included Pearson and Spearman; univariate and multivariate analysis for differences included χ‐square test and Student t tests for ordinal and continuous variables respectively. Results A total of 133 of 2,705 patients (4.6%) underwent bilateral hip arthroscopy. Radiographic alpha angle, magnetic resonance imaging alpha angle, lateral center edge angle, and anterior center edge angle demonstrated strong correlation (Pearson's coefficients 0.651, 0.648, 0.644, 0.667, respectively, P < .0001). Tönnis grade was weakly correlated (Pearson's coefficient 0.286, P = .001). Intraoperative pathology was moderately correlated (Pearson's coefficients for acetabular Outerbridge location, 0.300, P = .0170; acetabular labrum articular disruption, 0.490, P < .0001; acetabular Outerbridge; 0.530; P < .0001; femoral head Outerbridge, 0.459, P < .0001; Villar class, 0.393, P < .0001; and labral tear location, 0.468, P < .0001). Labral tear Seldes type was compared with Bowker's symmetry test and there was no significant difference between sides. There were no significant differences in surgical interventions performed between sides. Patients with bilateral hip arthroscopies significantly improved in all measured patient‐reported outcomes and had a high patient satisfaction after both procedures. Final patient‐reported outcomes and change in patient‐reported outcomes were not different between procedures; follow up ranged from 3 months to 8 years. Conclusions This study demonstrated an incidence of 4.6% of patients who require bilateral hip arthroscopy. These patients can expect significant improvement after surgical intervention. Patients that had 1 side done gained similar improvement when the contralateral side was performed. Preoperative radiographic, intraoperative pathology, and procedures performed were similar between hips. Level of Evidence Level III, retrospective cohort study.
Epidemiology of Hand and Wrist Injuries in NCAA Men’s Football: 2009–2010 to 2013–2014

Orthopaedic Journal of Sports Medicine | April 1, 2019 | Volume: 7 | Issue: 4 | Pages: No page available

10.1177/2325967119835375 | PMID 30968051

Background: Participation in National Collegiate Athletic Association (NCAA) football is at an all-time high. This population of athletes experiences a substantial injury burden, with many injuries affecting the upper extremities. Purpose/Hypothesis: The purpose of this study was to describe the epidemiology of hand and wrist injuries in college football players from the academic years 2009–2010 to 2013–2014. We hypothesized that variables such as event type (practice vs game), mechanism of injury, and player position would have an effect on the injury incidence. Study Design: Descriptive epidemiological study. Methods: An epidemiological study utilizing the NCAA Injury Surveillance Program was performed to investigate rates and patterns of hand and wrist injuries in participating varsity football teams from 2009–2010 to 2013–2014. Results: A total of 725 hand and wrist injuries were captured in 899,225 athlete-exposures. The observed practice injury rate was 0.51 injuries per 1000 athlete-exposures, compared with a game injury rate of 3.60 ( P < .01). Player-on-player contact was the most common injury mechanism reported, with blocking being the most common activity at the time of injury. Offensive linemen were most likely to experience an injury. Of all injuries sustained, 71.4% resulted in no time loss from competition, whereas 9.8% of injuries resulted in longer than 7 days of time loss. A fracture resulted in the greatest time loss from competition (mean ± SD, 8.3 ± 24.0 days; median, 0 days [range, 0-148 days] for injuries sustained in a practice setting) (mean ± SD, 7.7 ± 15.8 days; median, 0 days [range, 0-87 days] for injuries sustained in a game setting). Conclusion: Hand and wrist injuries were found to be significantly more common in games when compared with practices. This study provides valuable prognostic data regarding expected time loss on a per-injury pattern basis. Further investigation on specific injury subtypes and expected time loss as a result of these injures would provide trainers, players, and coaches with useful information on an expected postinjury recovery and rehabilitation timeline.
Osteomeniscal Impact Edema (OMIE): Description of a Distinct MRI Finding in Displaced Flap Tears of the Medial Meniscus, with Comparison to Posterior Root Tears

The Journal of Knee Surgery | March 28, 2019 | Volume: 33 | Issue: 07 | Pages: 659-665

10.1055/s-0039-1683938 | PMID 30921819

AbstractBone marrow edema (BME) can be a late finding in osteoarthritis or a sign of subchondral insufficiency. The purpose of this study was to describe the magnetic resonance imaging (MRI) finding we refer to as “osteomeniscal impact edema” (OMIE), or reactive BME adjacent to a displaced meniscus flap tear. In addition, this edema pattern is compared with a control group of medial meniscus posterior root tears (MMPRT) with subchondral insufficiency edema. MRI records from 2000 to 2017 were retrospectively reviewed for studies that showed the presence of a medial meniscus displaced flap tear and an adjacent area of BME. The selected MRIs were matched to an equal number of MMPRT MRI studies. All MRI studies were assessed for cartilage surface grade using the modified Outerbridge classification system and for the extent of accompanying structural abnormalities using the whole-organ magnetic resonance imaging score. Descriptive statistics and hypothesis testing were utilized to compare the MRI findings between groups. Twenty-two flap tear (OMIE group) patients with a mean age of 57 (SD: 15) and 22 root tear (MMPRT) group patients with a mean age of 61 (SD: 10) were included. MRIs in the OMIE group showed a distinctive pattern of focal, peripheral edema adjacent to the meniscus flap tear, compared with more diffuse, central edema in the MMPRT group. Quantitatively, MRIs of the MMPRT group showed significantly worse mean femoral Outerbridge scores (3.72 vs. 2.68, p < 0.0001), more severe central (1.63 vs. 0.5, p = 0.0007) and posterior (0.31 vs. 0.0, p = 0.04) subchondral edema grades, and a higher incidence of tibial subchondral fractures (3 vs. 0, p = 0.036). Meniscus flap tears may present with a distinct MRI pattern of focal, adjacent, peripheral edema, which we refer to as OMIE. Patients with meniscus flap tears showed significantly less arthritic change, lower subchondral edema grades, and a lower incidence of insufficiency fractures and subchondral collapse compared with the diffuse overload edema pattern found with root tears. The Level of Evidence for this study is III.
A Versatile Protocol for Studying Anterior Cruciate Ligament Reconstruction in a Rabbit Model

Tissue Engineering Part C: Methods | March 19, 2019 | Volume: 25 | Issue: 4 | Pages: 191-196

10.1089/ten.tec.2018.0357 | PMID 30887885

Correction to: Anterior cruciate ligament reconstruction with concomitant meniscal surgery: a systematic review and meta‐analysis of outcomes

Knee Surgery, Sports Traumatology, Arthroscopy | March 13, 2019 | Volume: 27 | Issue: 11 | Pages: 3453-3453

10.1007/s00167-019-05409-2 | PMID 30868187

Unfortunately, the middle name of Olufemi R. Ayeni was accidentally omitted in the original publication and the author name is corrected here. The original article has been corrected.
Long-term Results After Repair of Isolated Meniscal Tears Among Patients Aged 18 Years and Younger: An 18-Year Follow-up Study

The American Journal of Sports Medicine | February 25, 2019 | Volume: 47 | Issue: 4 | Pages: 799-806

10.1177/0363546519826088 | PMID 30802135

Background: Meniscal repair is desirable over resection to prevent postmeniscectomy arthritis, especially among young and active patients. However, long-term data are currently lacking following isolated meniscal repair, particularly in the pediatric population. Purpose/Hypothesis: To report long-term follow-up of isolated meniscal tears treated by meniscal repair in a pediatric and adolescent population and to compare those results with previous midterm follow-up data reported. The authors hypothesized that these patients would have satisfactory function and reoperation rates at long-term follow-up. Study Design: Case series; Level of evidence, 4. Methods: Forty-four patients aged ≤18 years undergoing repair of an isolated meniscal tear (without concomitant anterior cruciate ligament injury) between 1990 and 2005 were included. At the time of final follow-up, recurrent tear, reoperations, and International Knee Documentation Committee (IKDC) and Tegner scores were determined. With logistic regression, the overall failure among tear types was calculated. Wilcoxon rank sum analysis were performed to calculate the differences in clinical outcome for different time points, and Spearman coefficients were calculated for Tegner and IKDC with different variables. Results: At a mean follow-up of 17.6 years (range, 13.1-25.9 years), 32 patients with 33 isolated meniscal repairs (29 male, 3 female) with a mean age of 16.1 years (range, 9.9-18.7 years) at surgery were included in this study. At early follow-up, the overall failure rate was 14 of 33 (42%); complex tears (80%) and bucket-handle tears (47%) had higher overall failure rates when compared with simple tears (18.2%), although only complex tears had a significantly higher failure rate. However, no further failures occurred since midterm follow-up with any tear type. At final follow-up, the mean IKDC score was 92.3, which was significantly increased when compared with preoperative (65.3, P < .0001) and midterm (90.2, P = .01) scores. The mean Tegner score (6.5) was significantly lower than both preoperative (8.3, P < .0001) and midterm (8.4, P < .0001) scores. There was no difference in Tegner or IKDC score for patients with successful versus failed repair. Conclusion: In conclusion, while there was a high early failure rate, this study demonstrated overall good to excellent long-term clinical outcomes after isolated meniscal repair in an adolescent population, even for those requiring reoperation. Early failure and reoperation rates were variable, depending on tear type, with complex multiplanar tears having more failures at short-term follow-up. However, at long-term follow-up, IKDC and Tegner scores were not significantly different for those with complex tears as compared with other tear types.
Anterior cruciate ligament reconstruction with concomitant meniscal surgery: a systematic review and meta‐analysis of outcomes

Knee Surgery, Sports Traumatology, Arthroscopy | February 4, 2019 | Volume: 27 | Issue: 11 | Pages: 3441-3452

10.1007/s00167-019-05389-3 | PMID 30719542

AbstractPurposeThe aim of this review was to compare the clinical outcomes of anterior cruciate ligament reconstruction (ACLR) with either meniscal repair or meniscectomy for concomitant meniscal injury. The primary hypothesis was that short‐term clinical outcomes (≤ 2‐year follow‐up) for ACLR concomitant with either meniscal repair or resection would be similar. The secondary hypothesis was that ACLR with meniscal repair would result in better longer term outcomes compared with meniscal resection.MethodsThe authors searched two online databases (EMBASE and MEDLINE) from inception until March 2018 for the literature on ACLR and concurrent meniscal surgery. Two reviewers systematically screened studies in duplicate, independently, and based on a priori criteria. Quality assessment was also performed in duplicate. The Knee injury and Osteoarthritis Outcome Score (KOOS) sub‐scale scores at 2 years post‐operatively were combined in a meta‐analysis of proportions using a random‐effects model.ResultsOf 2566 initial studies, 25 studies satisfied full‐text inclusion criteria. Mean follow‐up was 2.09 years, with a total sample of 37,087 subjects including controls. The meta‐analysis demonstrated equivocal results at 2 years, except for KOOS symptom scores which favoured meniscal resection over repair. Mean KT‐1000 side‐to‐side difference (SSD) scores were 1.51 ± 0.60 mm for meniscal repair, 1.96 ± 0.36 mm for meniscal resection, and 1.58 ± 0.20 for control patients (isolated ACLR). Medial meniscal repair showed decreased anterior knee joint laxity compared to medial meniscal resection (P < 0.001). Patients with meniscal repair had higher rates of re‐operation (13.3% vs 0.8% for meniscal resection, P < 0.001).ConclusionPatients with ACLR combined with meniscal resection demonstrate better symptoms at 2‐year follow‐up compared to patients with ACLR combined with meniscal repair. ACLR combined with meniscal repair results in decreased anterior knee joint laxity with evidence of improved patient‐reported outcomes in the long term, but also higher re‐operation rates.Level of evidenceIII.
Anterior Cruciate Ligament Reconstruction With Hamstring Autograft: A Matched Cohort Comparison of the All-Inside and Complete Tibial Tunnel Techniques

Orthopaedic Journal of Sports Medicine | January 8, 2019 | Volume: 7 | Issue: 1 | Pages: No page available

10.1177/2325967118820297 | PMID 30671490

Background: Surgical reconstruction of the anterior cruciate ligament (ACL) is one of the most common orthopaedic procedures, with an estimated 100,000 to 175,000 procedures performed annually. Recently, the all-inside reconstruction technique has come into favor and is theorized to be superior to the complete tibial tunnel technique. Purpose: To compare clinical and patient-reported outcomes (PROs) for hamstring autograft ACL reconstruction (ACLR) performed with an all-inside versus a complete tibial tunnel technique. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent hamstring autograft ACLR via either an all-inside approach (femoral and tibial sockets) or a complete tibial tunnel approach (femoral socket and full-length, transtibial tunnel) at a single institution between July 2011 and July 2015 were reviewed. Demographic information, preoperative comorbidities, surgical details, physical examination findings, and follow-up outcomes were extracted from the medical record. Physical examination data included pivot-shift, Lachman, and range of motion examinations, whereas PROs included the Tegner activity scale, Lysholm score, and International Knee Documentation Committee (IKDC) score at a minimum of 2 years after surgery. Return to sport and risk factors for failure were analyzed. Results: A total of 82 patients (mean ± SD age, 25.8 ± 10.2 years) who underwent all-inside reconstruction (median PRO follow-up, 30.1 months; range, 24.7-72.9 months) and 54 patients (mean ± SD age, 21.1 ± 7.3 years) who underwent complete tibial tunnel reconstruction (median PRO follow-up, 25.8 months; range, 23.9-74.5 months) met the inclusion criteria. PRO scores at latest follow-up were comparable between the all-inside versus the complete tibial tunnel groups (Lysholm score, 93.8 vs 94.4, P = .621; IKDC score, 93.5 vs 93.3, P = .497; Tegner activity score, 6.4 vs 6.8, P = .048). Complications (including graft failure) were experienced by 20% of patients in the all-inside group compared with 24% in the complete tibial tunnel group ( P = .530). Graft failure before the final follow-up was experienced by 10% of patients in the all-inside group compared with 19% in the complete tibial tunnel group ( P = .200). Mean return to sport was 12.5 months in the all-inside group versus 9.9 months in the complete tibial tunnel group ( P = .028). Conclusion: All-inside and complete tibial tunnel hamstring autograft ACLR resulted in excellent physical examination findings and PROs at minimum 2-year follow-up. Both techniques successfully restored knee stability and patient function.