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Johnson, Nick R.

Mayo Clinic

Mayo Clinic

Citations 20

Nonoperative Management of Posterior Shoulder Instability: An Assessment of Survival and Predictors for Conversion to Surgery at 1 to 10 Years After Diagnosis
Lee, Julia , Johnson, Nick R., Wu, Isabella T. , Dahm, Diane L., Krych, Aaron J. , Woodmass, Jarret M, Krych, Aaron J , Woodmass, Jarret Murray , Camp, Christopher L.

Arthroscopy | June 10, 2019 | Volume: 35 | Issue: 7 | Pages: 1964-1970

10.1016/j.arthro.2019.01.056 Get It

Purpose To (1) define the rate of delayed surgery, between 1 and 10 years after injury, in a population‐based study of patients with posterior shoulder instability (PSI), (2) evaluate predictive factors associated with delayed repair, and (3) identify differences between the nonoperative and operative groups at long‐term follow‐up. Methods A population‐based retrospectively reviewed study of all patients with PSI from January 1, 1994, to December 31, 2015, was performed. Inclusion required a clinical diagnosis of PSI combined with supporting imaging. Complete medical records were reviewed for 2,091 potential cases. Kaplan‐Meier estimates were used to calculate survival. Landmark survival analysis was performed to identify predictors of conversion to surgery. Results The study included 143 patients with PSI, 79 of whom were managed nonoperatively for at least 1 year after diagnosis. After the first year, survival free of surgery was 78.3% at 1 year, 63.1% at 5 years, and 51.5% at 10 years. There was a trend toward increased surgery in patients with a body mass index > 35 ( P = .10; hazard ratio = 2.32; confidence interval, 0.8‐6.8). Nonthrowing athletes (including contact/weight‐lifting athletes) showed a trend toward an increased risk for surgery ( P = . 07). Patients who underwent surgery were significantly more likely to have progression in arthritis ( P = . 02; hazard ratio = 4.0; confidence interval, 1.2‐13.2). Conclusions Nonoperative management was performed for at least 1 year in over half of patients diagnosed with PSI. Overall, long‐term follow‐up demonstrates that 46% of these patients converted to surgery between 1 and 10 years after initial diagnosis. Ultimately, 70% of patients diagnosed with PSI go on to surgical intervention. Patients who underwent surgery at any time point were at an increased risk of radiographic progression of arthritis at a minimum of 5 years of follow‐up. Level of Evidence Level III, cohort study.
Non-operative Management of Posterior Shoulder Instability: An Assessment of Survival and Predictors for Conversion to Surgery at 1 to 13 Years After Diagnosis
Lee, Julia , Johnson, Nick R., Dahm, Diane L., Woodmass, Jarret Murray , Camp, Christopher L. , Krych, Aaron J.

Orthopaedic Journal of Sports Medicine | July 27, 2018 | Volume: 6 | Issue: 7_suppl4 | Pages: No page available

10.1177/2325967118s00098 Get It

Objectives: Among patients treated non-operatively for 1 year following a diagnosis of posterior shoulder instability (PSI), little is known about the the incidence of surgery between 1-13 years after injury. The purpose of this study is to define the frequency and evaluate the factors predictive for late surgical intervention of symptomatic PSI. Methods: This study included a population-based cohort of 115 patients (14 females, 101 males) diagnosed with PSI between January 1994 and July 2012 with a minimum 5-years follow-up (mean:13.9 years; range: 5-23 years). Landmark survival analysis was performed to evaluate incidence of surgery after 1 year. Survival was estimated using Kaplan Meier method and predictors of late surgical intervention were analyzed using Cox proportional hazards regression. Results: A total of 61/115 (53%) patients were treated non-operatively for 1 year following diagnosis of PSI. Of these, 24/61 (39%) converted to surgery for symptomatic PSI. The overall survival free of surgery at 1 and 5 years was 53.0% (95% CI 434.7-63.0) and 37.1% (95% CI 29.1-47.1), respectively. BMI >35 (p=0.04, HR 3.3) was predictive for late conversion to surgery. Age, gender, occupation, or history of glenohumeral dislocation were not significant. Assessing surgery as a time dependent covariate, a patient undergoing surgery was at an increased risk for radiographic progression of osteoarthritis (p=0.02, HR=4.0, 95% CI 1.2-13.2). Conclusion: Conservative management was performed for at least one year in over half of patients diagnosed with PSI. However, long-term follow-up demonstrates that nearly 40% of these patients eventually require surgery. Increased BMI was predictive for late failure of while age, gender, history of dislocation and occupation did not show an effect. Patients who underwent surgery were at an increased risk of radiographic progression of arthritis.
Combined Tibial Tubercle Osteotomy and Medial Patellofemoral Ligament Reconstruction for Recurrent Lateral Patellar Instability in Patients With Multiple Anatomic Risk Factors
Allen, Melissa M. , Krych, Aaron J. , Johnson, Nick R., Mohan, Rohith , Dahm, Diane L., Krych, Aaron J , Stuart, Michael J.

Arthroscopy | May 19, 2018 | Volume: 34 | Issue: 8 | Pages: 2420

10.1016/j.arthro.2018.02.049 Get It

Purpose To report the outcomes for combined tibial tubercle osteotomy (TTO) and medial patellofemoral ligament (MPFL) reconstruction and assess for potential risk factors for recurrent instability and/or poor outcomes. Methods The medical record at our institution was reviewed for patients treated with MPFL reconstruction and TTO for recurrent lateral patellar instability from 1998 to 2014. Preoperative imaging was assessed for trochlear dysplasia according to the Dejour classification (high grade = B, C, D) and the presence of patella alta using the Caton‐Deschamps ratio (>1.2). The indication for combined MPFL reconstruction and TTO was MPFL insufficiency and a lateralized tibial tubercle. Outcomes were determined by recurrent instability, return to sport, and Kujala and International Knee Documentation Committee (IKDC) scores. Results Thirty knees in 28 patients (14 M, 14 F) with a mean age of 22.6 ± 9.1 years (range, 13‐51 years) were included with a mean follow‐up of 48 ± 28 months (24‐123 months). Seventy‐three percent (22/30) had high‐grade trochlear dysplasia, and 63% (19/30) had patella alta. One patient had a postoperative dislocation and 1 had a subluxation event. The Caton‐Deschamps ratio decreased by a mean of 0.2 ( P = .001), leaving 30% with postoperative patella alta. The mean postoperative scores were as follows: Tegner = 5 ± 2, Kujala = 89 ± 16 (45‐100), and IKDC = 85 ± 17 (44‐100). Eighty‐three percent (15/18) returned to their preoperative sport. Female gender was a risk factor for lower IKDC (77.3 vs. 92.6, P = .01) and Kujala (82.2 vs. 95.0, P = .03) scores. Medialization greater than 10 mm was directly correlated to lower IKDC ( P = .02) and Kujala ( P = .01) scores. Conclusions The combination of MPFL reconstruction and TTO in patients with trochlear dysplasia results in low recurrence of instability. Patients on average had good subjective outcomes and were able to return to sport. Female gender and tibial tubercle medialization greater than 10 mm were associated with worse outcomes. Level of Evidence Level IV, therapeutic case series.
Posterolateral Corner Reconstruction Using the Anatomical Two-Tailed Graft Technique: Clinical Outcomes in the Multiligament Injured Knee
Sanders, Thomas L. , Wu, Isabella T. , Krych, Aaron J. , Levy, Bruce A. , Woodmass, Jarret M, Johnson, Nick R., Krych, Aaron J , Woodmass, Jarret Murray , Johnson, Nick A. , Stuart, Michael J.

The Journal of Knee Surgery | February 14, 2018 | Volume: 31 | Issue: 10 | Pages: 1031-1036

10.1055/s-0038-1632377 Get It

AbstractInjury to the posterolateral corner (PLC) of the knee can lead to both varus and rotational instability. Multiple PLC reconstruction techniques have been described, including one-tailed graft (fibula-based constructs) or two-tailed graft (combined fibula- and tibia-based constructs). The purpose of our study was to evaluate the clinical outcomes of anatomical two-tailed graft reconstruction of the PLC in the setting of multiligament knee injuries (MKLIs) with grade III varus instability. Patients were identified through a prospective MLKI database between 2004 and 2013. Patients who received fibular collateral ligament and PLC reconstructions using a two-tailed graft and had a minimum follow-up of 2 years were included. Patients were assessed for clinical laxity grade, range of motion, and functional outcomes using Lysholm and International Knee Documentation Committee (IKDC) scores. Twenty patients (16 male, 4 female) with a mean age of 30.7 (range: 16–52) and a mean follow-up of 52.2 months (range: 24–93 months) were included. Knee dislocation (KD) grades included: 4 KD-1, 10 KD 3-L, 5 KD-4, and 1 KD-5. No patients had isolated PLC injuries. Mean IKDC and Lysholm score were 73.1 ± 25.8 and 78 ± 26, respectively. Mean range of motion was –1.1 to 122.8. In full extension, two patients (10%) had grade 1 laxity to varus stress. In 30 degrees of knee flexion, five (25%) patients had grade 1 laxity, and two (10%) had grade 2 laxity. Anatomical two-tailed PLC reconstruction can reliably restore varus stability when performed on patients with MLKIs and type C posterolateral instability with hyperextension external rotation recurvatum deformity. Satisfactory functional outcome scores were achieved in the majority of patients. This study supports the use of an anatomical two-tailed PLC reconstruction in the multiligament injured knee. The level of evidence is IV, case series.
Medial Patellofemoral Ligament Reconstruction Reduces Radiographic Measures of Patella Alta in Adults
Johnson, Nick R., Cates, Robert A. , Krych, Aaron J. , Dahm, Diane L., Woodmass, Jarret M, Krych, Aaron J , Woodmass, Jarret Murray , Stuart, Michael J.

Orthopaedic Journal of Sports Medicine | January 25, 2018 | Volume: 6 | Issue: 1 | Pages: No page available

10.1177/2325967117751659 Get It

Background: Patellar height has long been considered a risk factor for patellofemoral instability. However, recent pediatric literature demonstrated a reduction in patellar height measurements following medial patellofemoral ligament (MPFL) reconstruction. Purpose: To assess the mean change in patellar height and the percentage of skeletally mature patients with patellar height ratios reduced to within-normal limits following MPFL reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Adult patients undergoing primary MPFL reconstruction for recurrent lateral patellar instability between 2005 and 2013 were identified. Pre- and postoperative (within 1 year of surgery) lateral knee radiographs were assessed for patellar height indices, including Caton-Deschamps, Blackburne-Peel, and Insall-Salvati ratios. The change in patellar height and the number of patients reduced from abnormal to normal patellar height ratios following MPFL reconstruction were assessed. Results: Overall, 32 adult patients were included in the study, with a mean age of 25.7 years (range, 18-55 years). There were 21 women (66%) and 11 men (34%). Insall-Salvati, Blackburne-Peel, and Caton-Deschamps ratios all demonstrated significant reductions in patellar height between pre- and postoperative lateral knee radiographs ( P < .001). All 3 indices showed a reduction in the number of patients meeting the criteria for patella alta following MPFL reconstruction. A total of 64% of patients had an abnormal preoperative Caton-Deschamps ratio reduced to within normal limits postoperatively. Conclusion: MPFL reconstruction provides a consistent reduction in patellar height measurements. The Caton-Deschamps ratio was reduced to the reference range following MPFL reconstruction in 64% of patients with preoperative patella alta. Surgeons treating patellofemoral instability should expect a reduction in patellar height after ligament reconstruction, which may affect the need for more invasive distalization procedures.
Is Treatment of Segond Fracture Necessary With Combined Anterior Cruciate Ligament Reconstruction?
Melugin, Heath P. , Johnson, Nick R., Wu, Isabella T. , Levy, Bruce A. , Krych, Aaron J. , Krych, Aaron J , Stuart, Michael J.

The American Journal of Sports Medicine | December 29, 2017 | Volume: 46 | Issue: 4 | Pages: 832-838

10.1177/0363546517745280 Get It

Background: There is a paucity of clinical information to guide the treatment of a combined anterior cruciate ligament (ACL) tear and Segond fracture. Purpose: To compare clinical outcomes, graft failure rates, and activity levels between patients undergoing ACL reconstruction (ACLR) with and without an untreated Segond fracture at a minimum 2-year follow-up. Study Design: Cohort study; Level of evidence, 3. Methods: This study included a group of patients with a combined ACL tear/untreated Segond fracture that was matched based on age, sex, body mass index, and graft type to a control group of patients with an ACL tear and no Segond fracture. All patients were treated with ACLR alone between the years of 2000 and 2015. The diagnosis of a Segond fracture, or bony avulsion of the anterolateral complex, was made by radiographic analysis. Data regarding the initial injury, surgical intervention, and physical examination findings were recorded. Clinical and functional outcomes were obtained using physical examination results, International Knee Documentation Committee (IKDC) subjective scores, and Tegner activity levels. Results: Twenty patients (16 male, 4 female) with a combined ACL tear/untreated Segond fracture with a mean age of 26.3 years (range, 13-44 years) were matched to a control group of 40 patients (32 male, 8 female) with an ACL tear and no Segond fracture with a mean age of 26.4 years (range, 13-47 years). The study group was followed for a mean of 59.1 months (range, 24-180 months) and the control group for a mean of 55.5 months (range, 24-120 months). The mean IKDC score was 86.5 (range, 54-100) for the study group compared with 93.0 (range, 54-100) for the control group ( P = .03). The graft rupture rate was 10% for both groups ( P = .97). The mean time to rupture was 33.0 months (range, 21-45 months) in the study group and 63.5 months (range, 39-88 months) in the control group ( P = .24). Patients in the study group had significantly more anteroposterior instability by preoperative Lachman testing than those in the control group (control group: 0 normal, 3 grade 1+, 37 grade 2+, 0 grade 3+; study group: 0 normal, 1 grade 1+, 10 grade 2+, 9 grade 3+; P = .0001). There was no significant difference between the 2 groups in regard to postoperative Lachman testing (control group: 35 normal, 3 grade 1+, 2 grade 2+, 0 grade 3+; study group: 17 normal, 3 grade 1+, 0 grade 2+, 0 grade 3+; P = .31). Patients in the study group had significantly more instability by preoperative pivot-shift testing than those in the control group (control group: 0 normal, 7 grade 1+, 33 grade 2+, 0 grade 3+; study group: 1 normal, 1 grade 1+, 11 grade 2+, 7 grade 3+; P = .0003). No significant difference was found between the 2 groups for postoperative pivot-shift testing (control group: 36 normal, 2 grade 1+, 2 grade 2+, 0 grade 3+; study group: 18 normal, 1 grade 1+, 1 grade 2+, 0 grade 3+; P = .61) or final Tegner activity level (median, 6). Conclusion: At midterm follow-up, patients undergoing ACLR with and without a Segond fracture had similar pivot-shift test results, graft failure rates, and activity levels. The IKDC score was statistically worse in the patients with a combined ACL tear/untreated Segond fracture, but the difference was less than the minimal clinically important difference for the IKDC score. These findings suggest that patients with a combined ACL tear/untreated Segond fracture can have comparable outcomes to patients with an ACL tear and no Segond fracture when treated with ACLR alone.
Revision Multiligament Knee Reconstruction: Clinical Outcomes and Proposed Treatment Algorithm
O’Malley, Michael, Krych, Aaron J. , Reardon, Patrick J., Johnson, Nick R., Levy, Bruce A. , Woodmass, Jarret M, O'Malley, Michael P, Krych, Aaron J , Woodmass, Jarret Murray , Stuart, Michael J.

Arthroscopy | December 19, 2017 | Volume: 34 | Issue: 3 | Pages: 736

10.1016/j.arthro.2017.09.022 Get It

Purpose To (1) assess clinical outcomes of revision multiligament knee injury (MLKI) reconstruction at a minimum of 2 years' follow‐up and (2) present a standardized treatment algorithm used in treating revision MLKI patients. Methods A retrospective review of our institution's MLKI database was performed to identify all patients who underwent revision MLKI reconstructions (≥2 ligaments reconstructed) after implementation of a standardized treatment algorithm in 2000 and had a minimum of 2 years' follow‐up. Patient demographic information, injury description (mechanism of injury, neurovascular status, knee dislocation grade, associated chondral or meniscal injury), surgical technique (repair vs reconstruction, staged vs nonstaged, concomitant procedures), mechanism of failure, knee stability, and range of motion, as well as International Knee Documentation Committee and Lysholm scores, were obtained. Results We assessed 23 patients (8 female and 15 male patients), with an average age of 26.7 ± 11.5 years at primary surgery and 30.8 ± 11.0 years at revision surgery. The mean follow‐up period was 7.5 ± 5.3 years. Of the 23 patients, 10 (43.4%) underwent staged revision procedures: isolated bone grafting in 3, osteotomy in 4, hardware removal with osteochondral allograft in 1, hardware removal with bone grafting in 1, and meniscus repair for a locked knee in 1. The average International Knee Documentation Committee and Lysholm scores were 74.5 ± 22.3 and 79.4 ± 20.2, respectively. High‐energy injury and increasing age at revision surgery were the only risk factors found to be associated with significantly worse outcomes ( P < .05). Conclusions Patients with recurrent instability after MLKI reconstruction present with many concomitant pathologies, including limb malalignment, bone tunnel widening, retained hardware, meniscal incompetence, and cartilage defects. Revision MLKI reconstruction can provide these patients with modest functional outcomes when a standardized treatment algorithm is used focusing on identification and treatment of the concomitant pathology, often in a staged manner. Level of Evidence Level IV, case series.
Multicenter Analysis of Midterm Clinical Outcomes of Arthroscopic Labral Repair in the Hip: Minimum 5-Year Follow-up
Krych, Aaron J. , Johnson, Nick R., Redmond, John M., Hartigan, David E. , Levy, Bruce A. , Domb, Benjamin G. , Krych, Aaron J , Hevesi, Mario

The American Journal of Sports Medicine | October 24, 2017 | Volume: 46 | Issue: 2 | Pages: 280-287

10.1177/0363546517734180 Get It

Background: The technique of hip arthroscopic surgery is advancing and becoming more commonly performed. However, most current reported results are limited to short-term follow-up, and therefore, the durability of the procedure is largely unknown. Purpose: To perform a multicenter analysis of mid-term clinical outcomes of arthroscopic hip labral repair and determine the risk factors for patient outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: Prospectively collected data of primary hip arthroscopic labral repair performed at 4 high-volume centers between 2008 and 2011 were reviewed retrospectively. Patients were assessed preoperatively and postoperatively with the visual analog scale (VAS), modified Harris Hip Score (mHHS), and Hip Outcome Score–Sports-Specific Subscale (HOS-SSS) at a minimum of 5 years’ follow-up. Factors including age, body mass index (BMI), Tönnis grade, and cartilage grade were analyzed in relation to outcome scores, and revision rates were determined. Failure was defined as subsequent ipsilateral hip surgery, including revision arthroscopic surgery and open hip surgery. Results: A total of 303 patients (101 male, 202 female) with a mean age of 32.0 years (range, 10.7-58.9 years) were followed for a mean of 5.7 years (range, 5.0-7.9 years). Patients achieved mean improvements in VAS of 3.5 points, mHHS of 20.1 points, and HOS-SSS of 29.3 points. Thirty-seven patients (12.2%) underwent revision arthroscopic surgery, and 12 (4.0%) underwent periacetabular osteotomy, resurfacing, or total hip arthroplasty during the study period. Patients with a BMI >30 kg/m 2 had a mean mHHS score 9.5 points lower and a mean HOS-SSS score 15.9 points lower than those with a BMI ≤30 kg/m 2 ( P < .01). Patients aged >35 years at surgery had a mean mHHS score 4.5 points lower and a HOS-SSS score 6.7 points lower than those aged ≤35 years ( P = .03). Patients with Tönnis grade 2 radiographs demonstrated a 12.5-point worse mHHS score ( P = .02) and a 23.0-point worse HOS-SSS score ( P < .01) when compared with patients with Tönnis grade 0. Conclusion: Patients demonstrated significant improvements in VAS, mHHS, and HOS-SSS scores after arthroscopic labral repair. However, those with Tönnis grade 2 changes preoperatively, BMI >30 kg/m 2 , and age >35 years at the time of surgery demonstrated significantly decreased mHHS and HOS-SSS scores at final follow-up.
Erratum: Arthritis Progression on Serial MRIs Following Diagnosis of Medial Meniscal Posterior Horn Root Tear
Johnson, Nick, Mohan, Rohith , Littrell, Laurel A. , Collins, Mark S., Krych, Aaron J. , Johnson, Nick R., Krych, Aaron J , Hevesi, Mario , Stuart, Michael J.

The Journal of Knee Surgery | October 11, 2017 | Volume: 31 | Issue: 07 | Pages: e1-e1

10.1055/s-0037-1607351 Get It

Paper #60: Risk Factors And Time To Recurrent Ipsilateral And Contralateral Patellar Dislocation: A Population‐Based Study
Christensen, Tyson C. , Sanders, Thomas L. , Pareek, Ayoosh , Johnson, Nick R., Mohan, Rohith , Dahm, Diane L., Krych, Aaron J.

Arthroscopy | September 29, 2017 | Volume: 33 | Issue: 10S | Pages: No page available

10.1016/j.arthro.2017.08.049 Get It