MBMatthew Bollier

Matthew Bollier

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Matthew Bollier has a total of 185 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Postoperative Bracing after Medial Patellofemoral Ligament Reconstruction

    by Andrew L. Schaver, Meaghan A. Tranovich, Olivia C. O'REilly, Matthew J. Bollier, Kyle R. Duchman, Brian R. Wolf, Robert W. Westermann

    It is unclear if bracing is necessary after isolated medial patellofemoral ligament reconstruction (MPFLr) for recurrent patellar instability. We hypothesize that patients who did not use a brace will have similar outcomes to those who were braced postoperatively. A retrospective review of patients who underwent isolated MPFLr from January 2015 to September 2020 at a single institution was performed. Those with less than 6 weeks of follow-up were excluded. The braced group was provided a hinged-knee brace postoperatively until the return of quadriceps function, which was determined by the treating physical therapist (brace, “B”; no brace, “NB”). Time to straight leg raise (SLR) without lag, recurrent instability, and total re-operations were determined. Univariate analysis and logistic regression were used to evaluate outcomes (statistical significance, p < 0.05). Overall, 229 isolated MPFLr were included (B: 165 knees, 146 patients; NB: 64 knees, 58 patients). Baseline demographics were similar (all p > 0.05). Median time to SLR without lag was shorter in the NB group (41 days [interquartile range [IQR]: 20–47] vs. 44 days [IQR: 35.5–88.3], p = 0.01), while return to sport times were equivalent (B: 155 days [IQR: 127.3–193.8] vs. NB: 145 days [IQR: 124–162], p = 0.31). Recurrent instability rates were not significantly different (B: 12 knees [7.27%] vs. NB: 1 knee [1.56%], p = 0.09), but the re-operation rate was higher in the brace group (20 knees [12.1%] vs. 0 [0%], p = 0.001). Regression analysis identified brace use (odds ratio [OR]: 19.63, 95% confidence interval [CI]: 1.43–269.40, p = 0.026) and female patients (OR: 2.79, 95% CI: 1.01–7.34, p = 0.049) to be associated with needing reoperation. Recurrent instability rates and return to sport times were similar between patients who did or did not use a hinged knee brace after isolated MPFLr. Re-operation rates were higher in the braced group. Retrospective Comparative Study, Level III


  • Graft Preparation with Intraoperative Vancomycin Decreases Infection After ACL Reconstruction

    by J.E. Baron, A.G. Shamrock, W.T. Cates, R.A. Cates, Q. An, B.R. Wolf, M.J. Bollier, K.R. Duchman, R.W. Westermann

    Background: Reported infection rates following anterior cruciate ligament (ACL) reconstruction are low, but infections are associated with high morbidity including reoperations and inferior clinical outcomes. The purpose of the current study was to investigate the rate of infection after ACL reconstruction with and without graft preparation with a vancomycin irrigant. Methods: All ACL reconstructions performed between May 2009 and August 2018 at a single academic institution were reviewed and categorized based on vancomycin use. Patients with <90-day follow-up, intraoperative graft preparation with an antibiotic other than vancomycin, or previous ipsilateral knee infection were excluded. Infection was defined as a return to the operating room for irrigation and debridement within 90 days after ACL reconstruction. Descriptive and inferential statistical analysis using t tests and Poisson regression were performed, with significance defined as p < 0.05. Results: In total, 1,640 patients (952 males; 58.0%) with a mean age (and standard deviation) of 27.7 ± 11.4 years underwent ACL reconstruction (1,379 primary procedures; 84.1%) and were included for analysis. Intraoperative vancomycin was used in 798 cases (48.7%), whereas 842 ACL reconstructions (51.3%) were performed without intraoperative vancomycin. In total, 11 reconstructions (0.7%) were followed by infection, which occurred in 10 (1.2%) of the patients in whom the graft was not soaked in vancomycin and in 1 (0.1%) of the patients in whom the graft was soaked in vancomycin (p = 0.032). Age (p = 0.571), sex (p = 0.707), smoking (p = 0.407), surgeon (p = 0.124), and insurance type (p = 0.616) were not associated with postoperative infection risk. Autograft use was associated with decreased infections (p = 0.045). There was an 89.4% relative risk reduction with the use of intraoperative vancomycin. An increased body mass index (BMI) (p = 0.029), increased operative time (p = 0.001), and the absence of ACL graft preparation with vancomycin (p = 0.032) independently predicted postoperative infection. Conclusions: The use of vancomycin-soaked grafts was associated with a 10-fold reduction in infection after ACL reconstruction (0.1% versus 1.2%; p = 0.032). Other risk factors for infection after ACL reconstruction included increased BMI and increased operative time. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


  • Open Access

    Performance of the PROMIS After Operative Interventions for Shoulder Instability

    by Christina J. Hajewski, Natalie A. Glass, Robert W. Westermann, Matthew Bollier, Brian R. Wolf, Carolyn Hettrich

    The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed to capture patient-reported outcomes (PROs) in an efficient manner. Few studies have assessed this instrument postoperatively. To compare the PROMIS Physical Function computer adaptive test (PROMIS PF CAT) and Upper Extremity (PROMIS UE) item bank to other previously validated PRO instruments and to evaluate ceiling and floor effects and construct validity responsiveness in patients who underwent operative interventions for shoulder instability. Cohort study (diagnosis); Level of evidence, 2. A total of 72 patients who underwent operative interventions for shoulder instability completed the American Shoulder and Elbow Surgeons (ASES) assessment form, Marx shoulder activity scale (Marx), 36-Item Short Form Health Survey physical function (SF-36 PF) and general health (SF-36 GH), Western Ontario Shoulder Instability Index (WOSI), PROMIS PF CAT, and PROMIS UE before surgery and then at 6 weeks and 6 months postoperatively. Correlation coefficients were calculated among these tools. The effect size of change was also calculated for each tool at each time point. A total of 91 patients who had also undergone surgery for shoulder instability completed these PRO instruments 2 years postoperatively. The percentage of patients hitting the ceiling and floor effects of each of the PRO instruments was calculated at all time points. The PROMIS PF CAT demonstrated excellent-good correlation with the SF-36 PF at all postoperative time points (0.61 at 6 weeks, 0.68 at 6 months, and 0.64 at 2 years; P < .01 for all). The PROMIS UE showed excellent correlation with the ASES at 6 weeks postoperatively (0.73, P < .01). Both the PROMIS PF CAT and PROMIS UE demonstrated the ability to detect change after surgical interventions with a medium to large effect size. The PROMIS UE demonstrated a ceiling effect at 6 months (68.1%) and 2 years (67.0%) postoperatively. The PROMIS PF CAT demonstrated no ceiling effect at any time point. The PROMIS PF CAT demonstrated good to excellent correlation with other previously validated PRO instruments that assess physical function in patients with shoulder instability postoperatively. The PROMIS UE demonstrated good correlation with other PRO tools but had a significant ceiling effect and is not recommended for this patient population. Both tools demonstrated an ability to detect change after surgical interventions with a good effect size.


  • PROMIS: a valid and efficient outcomes instrument for patients with ACL tears

    by Kyle John Hancock, Natalie Glass, Chris A. Anthony, Brian R. Wolf, Carolyn M. Hettrich, John Albright, Matt Bollier, Annunziato Amendola

    Purpose: The current study compares the Patient Reported Outcomes Information System Physical Function Computer Adaptive Test (PROMIS PF CAT) to traditional knee PRO instruments in a healthy population undergoing surgery for ACL injuries with the following objectives: (1) identify and determine the strength of any correlations between the scores of PROMIS PF CAT and current knee PROs or their subscales that measure physical function; (2) evaluate PROMIS PF CAT’s test burden; and (3) determine if PROMIS PF CAT has any floor or ceiling effects in this population.Methods: Patients indicated for ACL surgery completed the Short Form‐36 Physical Function (SF‐36 PF), Knee Injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale (Marx), the EuroQol 5‐dimensions Questionnaire (EQ‐5D), and PROMIS PF CAT. Correlations between PROs were defined as follows: High (≥ 0.7); high–moderate (0.61–0.69); moderate (0.4–0.6); moderate–weak (0.31–0.39); and weak (≤ 0.3). Floor or ceiling effects were considered significant if 15% or more patients reported the lowest or highest possible total score, respectively.Results: 100 patients participated with a mean age of 26 years (range 11–57). The PROMIS PF CAT demonstrated high correlations with SF‐36 PF (r = 0.82, p < 0.01), EQ‐5D (r = − 0.70, p < 0.01) KOOS ADL (r = 0.74, p < 0.01), and KOOS Sport (r = 0.70, p < 0.01). There were no ceiling or floor effects for PROMIS PF CAT (0%). The mean number of items completed for the PROMIS PF CAT was 4.2 (median 4; range 4–11).Conclusions: The PROMIS PF CAT shows a high correlation with commonly employed PROs that also measure physical function with low test burden and without ceiling effects in this relatively young and healthy population.


  • Current Concepts in Clinical Research: Anterior Cruciate Ligament Outcome Instruments

    by Molly Day, Kyle Hancock, Natalie Glass, Matthew Bollier

    Outcome instruments have become an essential part of the evaluation of functional recovery after anterior cruciate ligament (ACL) reconstruction. Although the clinical examination provides important objective information to assess graft integrity, stability, range of motion, and strength, these measurements do not take the patient’s perception into account. There are many knee outcome instruments, and it is challenging for surgeons to understand how to interpret clinical research and utilize these measures in a practical way. The purpose of this review is to provide an overview of the most commonly used outcome measures in patients undergoing ACL reconstruction and to examine and compare the psychometric performance (validity, reliability, responsiveness) of these measurement tools.

  • Open Access

    Performance of the PROMIS in Patients After Anterior Cruciate Ligament Reconstruction

    by Elizabeth J. Scott, Robert Westermann, Nathalie A. Glass, Carolyn Hettrich, Brian R. Wolf, Matthew J. Bollier

    The Patient-Reported Outcomes Measurement Information System (PROMIS) is designed to advance patient-reported outcome (PRO) instruments by utilizing question banks for major health domains. To compare the responsiveness and construct validity of the PROMIS physical function computer adaptive test (PF CAT) with current PRO instruments for patients before and up to 2 years after anterior cruciate ligament (ACL) reconstruction. Cohort study (diagnosis); Level of evidence, 2. Initially, 157 patients completed the PROMIS PF CAT, Short Form–36 Health Survey (SF-36 physical function [PF] and general health [GH]), Marx Activity Rating Scale (MARS), Knee injury and Osteoarthritis Outcome Score (KOOS activities of daily living [ADL], sport, and quality of life [QOL]), and EuroQol–5 dimensions questionnaire (EQ-5D) at 6 weeks, 6 months, and 2 years after ACL reconstruction. Correlations between instruments, ceiling and floor effects, effect sizes (Cohen d), and standardized response means to describe responsiveness were evaluated. Subgroup analyses compared participants with and without additional arthroscopic procedures using linear mixed models. At baseline, 6 weeks, and 6 months, the PROMIS PF CAT showed excellent or excellent-good correlations with the SF-36 PF (r = 0.75-0.80, P < .01), KOOS-ADL (r = 0.63-0.70, P < .01), and KOOS-sport (r = 0.32-0.69, P < .01); excellent-good correlation with the EQ-5D (r = 0.60-0.71, P < .01); and good correlation with the KOOS-QOL (r = 0.52-0.58, P < .01). As expected, there were poor correlations with the MARS (r = 0.00-0.24, P < .01) and SF-36 GH (r = 0.16-0.34, P < .01 ). At 2 years, the PROMIS PF CAT showed good to excellent correlations with all PRO instruments (r = 0.42-0.72, P < .01), including the MARS (r = 0.42, P < .01), indicating frequent return to preinjury function. The PROMIS PF CAT had the fewest ceiling or floor effects of all instruments tested, and patients answered, on average, 4 questions. There was no significant difference in baseline physical function scores between subgroups; at follow-up, all groups showed improvements in scores that were not statistically different. The PROMIS PF CAT is a valid tool to assess outcomes after ACL reconstruction up to 2 years after surgery, demonstrating the highest responsiveness to change with the fewest ceiling and floor effects and a low time burden among all instruments tested. The PROMIS PF CAT is a beneficial alternative for assessing physical function in adults before and after ACL reconstruction.


  • Surgical stabilization for first-time shoulder dislocators: a multicenter analysis

    by Caitlin M. Rugg, Carolyn M. Hettrich, Shannon Ortiz, Brian R. Wolf, Alan L. Zhang, Keith M. Baumgarten, Julie Y. Bishop, Matthew J. Bollier, Jonathan T. Bravman, Robert Brophy, et al.


  • Descriptive Epidemiology of the MOON Shoulder Instability Cohort

    by Matthew J. Kraeutler, Eric C. McCarty, John W. Belk, Brian R. Wolf, Carolyn M. Hettrich, Shannon F. Ortiz, MOON Shoulder Instability Group, Jonathan T. Bravman, Keith M. Baumgarten, Julie Y. Bishop, et al.

    Background: Shoulder instability is a common diagnosis among patients undergoing shoulder surgery. Purpose: To perform a descriptive analysis of patients undergoing surgery for shoulder instability through a large multicenter consortium. Study Design: Case series; Level of evidence, 4. Methods: All patients undergoing surgery for shoulder instability who were enrolled in the MOON Shoulder Instability Study were included. Baseline demographics included age, sex, body mass index, and race. Baseline patient-reported outcomes (PROs) included the American Shoulder and Elbow Surgeons (ASES) score, Shoulder Activity Score, Western Ontario Shoulder Instability Index (WOSI), 36-Item Health Survey (RAND-36), and Single Assessment Numeric Evaluation (SANE). The preoperative physician examination included active range of motion (ROM) and strength testing. Preoperative imaging assessments with plain radiography, magnetic resonance imaging (MRI), and computed tomography were also included and analyzed. Results: Twenty-six surgeons had enrolled 863 patients (709 male, 154 female) across 10 clinical sites. The mean age for the cohort was 24 years (range, 12-63 years). Male patients represented 82% of the cohort. The primary direction of instability was anterior for both male (74%) and female (73%) patients. Football (24%) and basketball (13%) were the most common sports in which the primary shoulder injury occurred. No clinically significant differences were found in preoperative ROM between the affected and unaffected sides for any measurement taken. Preoperative MRI scans were obtained in 798 patients (92%). An anterior labral tear was the most common injury found on preoperative MRI, seen in 66% of patients, followed by a Hill-Sachs lesion in 41%. Poor PRO scores were recorded preoperatively (mean: ASES, 72.4; WOSI, 43.3; SANE, 46.6). Conclusion: The MOON Shoulder Instability Study has enrolled the largest cohort of patients undergoing shoulder stabilization to date. Anterior instability is most common among shoulder instability patients, and most patients undergoing shoulder stabilization are in their early 20s or younger. The results of this study provide important epidemiological information for patients undergoing shoulder stabilization surgery.


  • Open Access

    Performance of PROMIS Physical Function Compared with KOOS, SF-36, Eq5d And Marx Activity Scale in Patients Who Undergo ACL Reconstruction

    by Elizabeth Scott, Natalie Glass, Brian R. Wolf, Carolyn M. Hettrich, Matthew Bollier

    Objectives: Anterior cruciate ligament reconstruction is a commonly performed orthopaedic procedure. PROMIS (Patient-Reported Outcome Measurement Information System) was developed by the National Institutes of Health in an effort to advance patient-reported outcome (PRO) instruments by developing question banks for major health domains. Our goal was to compare the responsiveness and construct validity of the PROMIS physical function (PF) computer adaptive test (CAT) with current PRO instruments utilized in patients who undergo anterior cruciate ligament reconstruction. Methods: A total of 174 patients ages 14-53 scheduled to undergo anterior cruciate ligament reconstruction were asked to complete PROMIS PF-CAT, Short Form-36 Health Survey (SF36-PF and -GH), Marx activity rating scale (Marx), Knee Injury and Osteoarthritis Score (KOOS-ADL, -Sport, -QOL), and the EuroQol five dimensions questionnaire (EQ5D) at their preoperative visit. These surveys were repeated at six weeks and six months after surgery. Correlations between PRO instruments was defined as excellent (>0.7), excellent-good (0.61-0.7), good (0.4-0.6), and poor (0.2-0.3) using Spearman Correlation Coefficients. The effect size (Cohen d) and standardized response mean (SRM) were used to describe the responsiveness of each PRO at the 6 week and 6 month follow-up visits and were defined as small (0.2), medium (0.5) and large (0.8). Ceiling and floor effects were defined as present if ≥15% of participants scored the highest or lowest score on a PRO, respectively. Subgroup analyses were performed comparing change in PRO scores at follow-up between participants with and without additional arthroscopic procedures (meniscal debridement and/or repair, microfracture, or OATS vs ACL reconstruction only) using linear mixed models. Results: There were excellent and excellent-good correlations between the PROMIS PF-CAT and physical function PROs including the SF36-PF (r=0.75-0.80, p<.01), KOOS-ADL (r=0.62-0.70, p<.01) and KOOS-Sport (r=0.32-0.69, p<0.01) at most time points, respectively. There was also excellent-good correlation with the EQ5D (r=0.60-0.71, p<.01) and good correlation with the KOOS-QOL (r=0.52-0.58, p0.05) to poor correlation with Marx activity (r=0.24, p<0.01) and the SF36-GH (r=0.32-0.34, p<0.01). No ceiling or floor effects were noted for the PROMIS PF-CAT; there was a ceiling effect noted for KOOS-ADL at the 6 month visit (38.1%). Effect size estimates for physical function PROs increased from small to large changes from the 6 week to 6 month visits and were largest in the PROMIS PF-CAT (1.34) followed by KOOS-ADL (1.19) and SF36-PF (1.06). Patients answered on average 4 questions utilizing the PROMIS. Baseline subgroup analyses showed no significant differences in physical function PRO scores, and at follow-up, both groups showed significant improvement in physical function PRO scores that was not statistically different. Conclusion: Our results support the construct validity of the PROMIS PF-CAT in patients who undergo ACL reconstruction. Responsiveness to change was highest by 6 months postop and greater for the PROMIS PF-CAT than for other measures of physical function with no ceiling or floor effects and a low time-burden. Taken together, these findings suggest that the PROMIS PF-CAT is a beneficial alternative to measuring and tracking changes in physical function in adults undergoing ACL reconstruction.