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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

Treatment of Patellofemoral Cartilage Lesions in the Young, Active Patient

Journal of Knee Surgery | April 20, 2015 | Volume: 28 | Issue: 04 | Pages: 285-296

10.1055/s-0035-1549018 | PMID 25892008

Medial Patellofemoral Ligament Tears in the Setting of Multiligament Knee Injuries Rarely Cause Patellar Instability

The American Journal of Sports Medicine | March 26, 2015 | Volume: 43 | Issue: 6 | Pages: 1386-1390

10.1177/0363546515576902 | PMID 25807952

Background: Multiligament knee injuries (MLKIs) can also involve the medial patellofemoral ligament (MPFL), but there is a paucity of information regarding prevalence and relevance of MPFL involvement in this setting. Purpose: (1) To identify the prevalence of MPFL injury in MLKIs, (2) to determine whether an MPFL tear results in symptomatic patellar instability, and (3) to report clinical and functional outcomes of patients with and without MPFL tears after MLKI surgical reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: The records of all patients who underwent surgical reconstruction of MLKI (defined as a grade 3 injury of ≥2 ligaments) at a single institution from 2007 to 2010 were reviewed. Age, sex, knee dislocation classification (according to Schenck), and MRI findings were documented. All preoperative MRI scans were reviewed by an experienced musculoskeletal radiologist to determine the presence or absence of MPFL involvement. If an MPFL tear was present, its anatomic location and severity as well as the presence of patellar or lateral femoral condyle bone bruises were documented. Inclusion criteria included (1) MLKI treated at a single institution, (2) presence of MPFL tear on preoperative MRI, and (3) minimum 2-year clinical follow-up. Patellar instability symptoms were assessed with the Kujala Knee Questionnaire. Functional outcomes were measured using the International Knee Documentation Committee (IKDC) score. IKDC scores were compared between patients who sustained MLKIs with and without MPFL tears. There were 21 patients in each group. Results: Over the 4-year study period, 30 of 51 patients (59%) treated surgically for a MLKI had MRI evidence of an MPFL tear. Nine were lost to follow-up, leaving 21 patients for review. There were 13 complete (62%), 5 high-grade partial (24%), and 3 partial (14%) MPFL tears. Sixteen of 21 tears (76%) occurred at the proximal third, with the remainder exhibiting diffuse signal abnormality consistent with tearing throughout the length of the MPFL. The superficial medial collateral ligament was involved in all patients. In no case was the MPFL repaired or reconstructed. At mean follow-up of 3.6 years (range, 2.0-5.7 years), only 1 of 21 patients (5%) complained of patellofemoral instability symptoms whereas 20 of 21 patients (95%) did not experience patellar subluxation or dislocation. No significant difference was found when IKDC scores were compared between patients with and without an MPFL tear (mean ± SD, 65.5 ± 22.9 vs 79.4 ± 16.1; P = .07). Conclusion: MPFL tears occur frequently in patients with MLKI but rarely cause instability. In the majority of cases, MPFL tears do not need to be addressed at the time of surgery.
Arthroscopic‐Assisted Reduction and Percutaneous Fixation of Tibial Plateau Fractures

Arthroscopy Techniques | February 2, 2015 | Volume: 4 | Issue: 1 | Pages: No page available

10.1016/j.eats.2014.11.002 | PMID 25973374

Abstract Tibial plateau fractures present a difficult range of fractures to treat. Arthroscopy allows for a less invasive option when compared with arthrotomy. Furthermore, visualization of the articular surface arthroscopically can allow for a precise reduction and assessment of any concomitant injuries to the articular cartilage and meniscus. By use of arthroscopy, unicondylar lateral plateaus were traditionally approached through a laterally based metaphyseal window. However, in carefully selected patients and fracture patterns, a medially based, arthroscopic‐assisted approach can create long bony tunnels for subchondral support and allow for greater ease in fracture reduction. We present our technique using a medial approach for arthroscopic‐assisted fixation of lateral tibial plateau fractures. Technique Video video See video under supplementary data.
Arthroscopic Meniscal Root Repair Using a Ceterix NovoStitch Suture Passer

Arthroscopy Techniques | October 27, 2014 | Volume: 3 | Issue: 5 | Pages: No page available

10.1016/j.eats.2014.07.006 | PMID 25473622

Abstract Meniscal root injuries can compromise knee function and lead to early degenerative changes if not appropriately treated. Numerous techniques have been described; however, the technical difficulties in performing these repairs are well known. Furthermore, the relative strengths of various repair techniques have been examined. This article describes a single–working portal meniscal root repair technique using a double‐locking loop suture configuration with a novel suture‐passing device that offers a strong, reproducible repair construct. Technique Video video See video under supplementary data.
Results of Revision Anterior Shoulder Stabilization Surgery in Adolescent Athletes

Arthroscopy | July 30, 2014 | Volume: 30 | Issue: 11 | Pages: 1400-1405

10.1016/j.arthro.2014.05.037 | PMID 25085048

Purpose The purpose of this study was to determine failure rates, functional outcomes, and risk factors for failure after revision anterior shoulder stabilization surgery in high‐risk adolescent athletes. Methods Adolescent athletes who underwent primary anterior shoulder stabilization were reviewed. Patients undergoing subsequent revision stabilization surgery were identified and analyzed. Failure rates after revision surgery were assessed by Kaplan‐Meier analysis. Failure was defined as recurrent instability requiring reoperation. Functional outcomes included the Marx activity score; American Shoulder and Elbow Surgeons score; and University of California, Los Angeles score. The characteristics of patients who required reoperation for recurrent instability after revision surgery were compared with those of patients who required only a single revision to identify potential risk factors for failure. Results Of 90 patients who underwent primary anterior stabilization surgery, 15 (17%) had failure and underwent revision surgery (mean age, 16.6 years; age range, 14 to 18 years). The mean follow‐up period was 5.5 years (range, 2 to 12 years). Of the 15 revision patients, 5 (33%) had recurrent dislocations and required repeat revision stabilization surgery at a mean of 50 months (range, 22 to 102 months) after initial revision. No risk factors for failure were identified. The Kaplan‐Meier reoperation‐free estimates were 86% (95% confidence interval, 67% to 100%) at 24 months and 78% (95% confidence interval, 56% to 100%) at 48 months after revision surgery. The mean final Marx activity score was 14.8 (range, 5 to 20); American Shoulder and Elbow Surgeons score, 82.1 (range, 33 to 100); and University of California, Los Angeles score, 30.8 (range, 16 to 35). Conclusions At 5.5 years' follow‐up, adolescent athletes had a high failure rate of revision stabilization surgery and modest functional outcomes. We were unable to convincingly identify specific risk factors for failure of revision surgery. Level of Evidence Level IV, retrospective therapeutic case series.
Reliability of hip internal rotation range of motion measurement using a digital inclinometer

Knee Surgery, Sports Traumatology, Arthroscopy | June 10, 2014 | Volume: 23 | Issue: 9 | Pages: 2562-2567

10.1007/s00167-014-3096-0 | PMID 24912575

AbstractPurposeAssessment of hip internal rotation (IR) is a critical element in the evaluation of a painful hip, yet there currently exists no consistent method of determining this measurement. The purpose of this study is to report the intra‐rater and inter‐rater reliability of active and passive hip IR measurement using a digital inclinometer.MethodsTwenty‐five subjects (8 men, 17 women) with asymptomatic hip joints, and no known pathology between the ages of 22 and 42 participated. Two examiners measured hip IR for each subject using a digital inclinometer while visually monitoring pelvic motion. Measurements included passive IR, active IR, and active IR while internally rotating both legs simultaneously. Statistical analysis was performed including intra‐rater and inter‐rater reliability.ResultsThere was no significant difference in measured IR values. Mean range of motion values for all techniques and both examiners ranged from 30.7° to 32.8°. Intra‐rater reliability for examiner 1 ranged from 0.84 to 0.92. Inter‐rater reliability ranged from 0.89 to 0.93. Of the methods utilized, active IR of a single leg was the most responsive technique with a minimal detectable change value of 5.4°.ConclusionsClinical assessment of hip IR range of motion can be performed efficiently and reliably with a digital inclinometer along with visual monitoring of the pelvis for unwanted motion. Findings from this study support unilateral active hip IR in a seated position as a reliable and responsive technique for obtaining hip IR measurements.Level of evidenceIII.
High‐Resolution Molecular Validation of Self‐Renewal and Spontaneous Differentiation in Clinical‐Grade Adipose‐Tissue Derived Human Mesenchymal Stem Cells

Journal of Cellular Biochemistry | June 6, 2014 | Volume: 115 | Issue: 10 | Pages: 1816-1828

10.1002/jcb.24852 | PMID 24905804

AbstractImproving the effectiveness of adipose‐tissue derived human mesenchymal stromal/stem cells (AMSCs) for skeletal therapies requires a detailed characterization of mechanisms supporting cell proliferation and multi‐potency. We investigated the molecular phenotype of AMSCs that were either actively proliferating in platelet lysate or in a basal non‐proliferative state. Flow cytometry combined with high‐throughput RNA sequencing (RNASeq) and RT‐qPCR analyses validate that AMSCs express classic mesenchymal cell surface markers (e.g., CD44, CD73/NT5E, CD90/THY1, and CD105/ENG). Expression of CD90 is selectively elevated at confluence. Self‐renewing AMSCs express a standard cell cycle program that successively mediates DNA replication, chromatin packaging, cyto‐architectural enlargement, and mitotic division. Confluent AMSCs preferentially express genes involved in extracellular matrix (ECM) formation and cellular communication. For example, cell cycle‐related biomarkers (e.g., cyclins E2 and B2, transcription factor E2F1) and histone‐related genes (e.g., H4, HINFP, NPAT) are elevated in proliferating AMSCs, while ECM genes are strongly upregulated (>10‐fold) in quiescent AMSCs. AMSCs also express pluripotency genes (e.g., POU5F1, NANOG, KLF4) and early mesenchymal markers (e.g., NES, ACTA2) consistent with their multipotent phenotype. Strikingly, AMSCs modulate expression of WNT signaling components and switch production of WNT ligands (from WNT5A/WNT5B/WNT7B to WNT2/WNT2B), while upregulating WNT‐related genes (WISP2, SFRP2, and SFRP4). Furthermore, post‐proliferative AMSCs spontaneously express fibroblastic, osteogenic, chondrogenic, and adipogenic biomarkers when maintained in confluent cultures. Our findings validate the biological properties of self‐renewing and multi‐potent AMSCs by providing high‐resolution quality control data that support their clinical versatility. J. Cell. Biochem. 115: 1816–1828, 2014. © 2014 Wiley Periodicals, Inc.
Does Arthroscopic Knee Surgery Work?

Arthroscopy | March 19, 2014 | Volume: 30 | Issue: 5 | Pages: 544-545

10.1016/j.arthro.2014.02.012 | PMID 24642108

Abstract A recent randomized trial from the Finnish Degenerative Meniscal Lesion Study Group was published in the New England Journal of Medicine and attempted to determine the efficacy of partial meniscectomy without osteoarthritis. Patients were randomized to either arthroscopic partial meniscectomy or sham surgery. The authors concluded that the clinical outcomes after arthroscopic partial meniscectomy were no better than those after the sham surgical procedure. However, there are several important limitations of this trial that make it difficult to generalize to the 700,000 arthroscopic partial meniscectomies performed in the United States each year. In this small sample of 146 patients, patients with traumatic meniscal tears and locking symptoms—those most likely to benefit from a partial meniscectomy—were excluded. In addition, although patients with radiographic arthritis were excluded, most of the patients in the study had degenerative changes at the time of arthroscopy. Therefore it is difficult to determine whether the patients were symptomatic from their chondral degeneration or their degenerative meniscal tear. In our opinion this study does not change the role of surgery in current clinical practice. The primary indication for arthroscopic partial meniscectomy remains symptoms of well‐localized joint line pain with acute onset and mechanical symptoms such as catching or locking that have failed comprehensive nonoperative management.
Adverse Effect of Femoral Nerve Blockade on Quadriceps Strength and Function after ACL Reconstruction

Journal of Knee Surgery | March 12, 2014 | Volume: 28 | Issue: 01 | Pages: 083-088

10.1055/s-0034-1371769 | PMID 24622910

Factors associated with excellent 6‐month functional and isokinetic test results following ACL reconstruction

Knee Surgery, Sports Traumatology, Arthroscopy | February 14, 2014 | Volume: 23 | Issue: 4 | Pages: 1053-1059

10.1007/s00167-014-2869-9 | PMID 24531355

AbstractPurposeTo identify patient concomitant injury and surgical characteristics associated with 6‐month excellent functional and isokinetic testing results following anterior cruciate ligament (ACL) reconstruction.MethodsPatients that underwent ACL reconstruction by a single surgeon had isokinetic and functional testing performed with excellent 6‐month outcome defined as greater than 85 % in isokinetic strength and 90 % in functional tests (excellent 6‐month group vs. delayed 6‐month group). Patient concomitant injury and surgical factors were then analysed in univariate and multivariate statistical models to assess which characteristics predicted the excellent 6‐month group.ResultsThe 224 patients included 93 males and 131 females, with median age of 22 (range 12–59) years, body mass index (BMI) of 25.4 (range 17–44), and median Tegner activity score of 6 (range 2–10). Fifty‐two patients (23 %) were included in the excellent 6‐month group, while 172 patients (77 %) were in the delayed 6‐month group. In univariate analysis, favourable factors with the excellent 6‐month outcome group were younger age (24 vs. 27; p = 0.01), lower BMI (24.5 vs. 26.2; p = 0.03), and minimal articular cartilage damage (71 vs. 56 %; p = 0.048). In multivariate analysis, a negative effect was observed for patients older than 30 years that had ACL reconstruction with autograft (p = 0.0004).ConclusionFactors significantly associated with excellent 6‐month functional and isokinetic test results following ACL reconstruction included younger age, lower BMI, and minimal cartilage degeneration. The use of allograft was associated with improved functional and strength testing after ACL reconstruction in patients over 30 years of age.Level of evidencePrognostic/therapeutic study, Level III.