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Johnson, Andrew J

Mayo Clinic

Orthopedics and Sports Medicine Mayo Clinic.

Citations 3

A Systematic Review of Post-Procedural Rehabilitation Protocols following Percutaneous Needle Tenotomy and Ultrasonic Debridement for Gluteal, Proximal Hamstring, and Patellar Tendinopathy
Buttinger, Jessica N., Johnson, A, Twohey, Eric E. , Gibson, Dylan J. , Nagelli, Christopher V. , Johnson, Shelby E. , Romero, Joshua M., Johnson, Andrew J, Twohey, Eric , Romero, Joshua

American Journal of Physical Medicine & Rehabilitation | June 16, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1097/phm.0000000000003031 Get It

Objective: Percutaneous needle tenotomy (PNT) and ultrasonic debridement (UD) are minimally invasive interventions for the management of chronic tendinopathy. Despite their increasing use, no standardized, evidence-based rehabilitation guidelines currently exist to direct clinicians in post-procedural management. This systematic review aimed to characterize and synthesize reported rehabilitation protocols following PNT and UD for patellar, proximal hamstring, and gluteal tendinopathies. Design: Systematic Review Results: Twenty-seven studies met inclusion criteria, with patellar tendon procedures (n=13) being the most common, followed by gluteal (n=6), proximal hamstring (n=3), and multi-tendon protocols (n=5). Of the included studies, 21 (78%) utilized percutaneous needle tenotomy (PNT) and six (22%) used ultrasound debridement or Tenex. Exercise restrictions were mandated in 19 studies (70%), while 12 (44%) provided a detailed, structured rehabilitation program, frequently emphasizing eccentric loading for patellar and hamstring tendons. Weight-bearing limitations were uncommon, appearing in only three studies (11%). Fifteen studies (56%) combined the procedure with platelet-rich plasma (PRP). Pharmacological protocols also showed high variance, with NSAID restrictions ranging from 1 to 28 days and corticosteroid avoidance lasting between 10 days and one year. Overall, substantial variability remains regarding recommended activity progression, exercise initiation, and mechanical loading strategies across current research. Conclusion: PNT and UD appear effective for managing refractory tendinopathy, yet post-procedure rehabilitation guidelines remain inconsistent and supported by limited high-quality evidence. Future research should aim to identify key variables that guide individualized rehabilitation progressions, optimizing recovery timelines, and facilitating safe and efficient return to activity following PNT and UD procedures.
Current State of Baseball Interval Throwing Programs: A Systematic Review of Content, Structure, and Variability of Published Throwing Programs
Iyer, Sanathan, Simon, Karissa N. , Cherny, Chad E., Johnson, Andrew , Zajac, John M., Christoffer, Daniel J., Hellem, Aaron R., Finck, Adam N., Langhans, Mark T. , Boos, Alexander M. , Johnson, Andrew J, Camp, Christopher L. , Iyer, Sanathan, Johnson, Andrew J.

Sports Health: A Multidisciplinary Approach | April 29, 2025 | Volume: 17 | Issue: 6 | Pages: 1214-1224

10.1177/19417381251333402 Get It

Context: There is need for an up-to-date comprehensive review of baseball interval throwing programs in the literature. Objective: To (1) understand the origin and basis of interval throwing programs; (2) evaluate the content of programs in the peer-reviewed literature including target audience, initiation criteria, throwing specifics, arm care, and performance evaluation metrics; (3) classify these variables as well defined, ambiguous, or missing; and (4) analyze variability in key aspects including starting criteria, length, progression, and completion criteria. Data Sources: Medline, Embase, Cochrane Reviews, Web of Science, and Scopus Study Selection: The full text of studies, in English, had to be available. Included studies had to contain a complete interval throwing program designed for baseball players. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: Initial screening was conducted based on article title and abstract. Full text of the remaining articles was evaluated for fulfillment of inclusion criteria. Results: Nine studies initially met inclusion criteria. The programs’ comprehensiveness was poor, with a mean Interval Throwing Program Checklist score of 20 (range 14-23) on a scale of 0 to 30. There were a variety of components, including progressive long toss, weighted ball, and throwing mechanics exercises. The programs identified had significant heterogeneity in duration, intensity, progression, and focus. Overall, there was a significant lack of attempts at validation or formal study of efficacy for published throwing programs. Conclusion: Current published interval throwing programs are mostly variations of an original program published many years ago and were based on principles of progressive loading with pain as sign of injury that should be monitored carefully. However, these programs have minimal clinical validation and objective measures to quantify their effectiveness. This work identifies several limitations in the current literature and can serve as a foundation for future development of evidence-based interval throwing programs.
Reliability and Validity of Measuring Shoulder Internal and External Rotation Strength in Volleyball Specific Positions
Loepfe, John G., Nagelli, Christopher V. , Cherny, Chad E., Johnson, Andrew , Larson, Dirk R. , Johnson, Andrew J, Tagliero, Adam J. , Johnson, Andrew J.

International Journal of Sports Physical Therapy | March 31, 2025 | Volume: 20 | Issue: 4 | Pages: No page available

10.26603/001c.132170 Get It

Background Overhead athletes are susceptible to shoulder injuries, among which rotator cuff injuries are common and often directly associated with muscle weakness. Therefore, valid and reliable measures of rotator cuff strength at sport specific positions may be a vital part of sports physical therapy practice. Purpose: The current study aimed to determine the inter- and intra-tester reliability of measuring shoulder internal rotation (IR) and external rotation (ER) strength at a novel testing position, 130° of abduction and compared to the 90°/90° position. A secondary aim was to assess concurrent validity between measurements taken with the Humac® Norm™ Isokinetic Dynamometer (IKD) and Microfet® 2 hand-held dynamometer (HHD). Study Design Inter-Rater and Intra-Rater Reliability and Criterion Validity Methods Twenty-five (n=25) healthy participants were recruited for this study. Exclusion criteria included prior shoulder surgery, shoulder injury within the last three months, and contraindications to exercise according to ACSM guidelines. Participants performed maximal isometric shoulder external and internal rotation strength testing at both 90° and 130° of shoulder abduction. On the first day, participants were tested on the IKD at both positions, followed by each tester using the HHD. Participants returned 7-14 days later for repeat testing using the HHD only. ICC values were calculated for each rater, instrument, and testing position. Bland-Altman plots were created to establish limits of agreement. Minimal detectable change values were calculated. Results Inter- and intra-rater reliability for testing isometric strength using a hand-held dynamometer was good to excellent for both shoulder positions with ICC values consistently above 0.8. Concurrent validity between the HHD and IKD was poor to moderate with ICC values ranging from 0.1-0.4. However, Bland-Altman plots demonstrated that the difference in strength measures was within the limits of agreement. Conclusion Shoulder IR and ER strength testing at 130° of abduction shows strong inter-rater and intra-rater reliability for measurement in sport specific positions. Level of Evidence Level 3