Internal impingement, often called the thrower's shoulder, describes the normal contact between the posterosuperior rotator cuff and labrum in the ABER position that becomes painful when posterior capsule contracture creates GIRD. This video explains how a tight posterior capsule shifts the humeral head, increases contact force, and leads to undersurface cuff tears and labral fraying. Learn the pathophysiology, diagnostic clues, and evidence‑based management. ⏱ Chapters 0:00 Intro 0:30 The Contact That Is Normal 1:40 The Contact, On MRI And Under The Scope 3:13 Measuring The Thrower 5:10 Measure The Arc — Scapula Held Down 6:33 Rehab First 7:41 Undersurface Tear — Measure The Residual… 8:16 Surgery As Salvage 9:24 Tighten — Or Preserve? 10:24 Repair Without Completing The Tear 11:44 Recap & sources This episode breaks down the mechanics of internal impingement in overhead athletes, detailing the normal ABER contact, the role of posterior capsule contracture and GIRD, imaging findings on MRI and arthroscopy, and the stepwise treatment algorithm from conservative stretching to surgical debridement or repair. Understanding these concepts is essential for clinicians managing shoulder pain in throwers and for anyone seeking to prevent progression to full‑thickness tears. 🦴 IN THIS VIDEO YOU'LL LEARN • How normal posterosuperior cuff‑labrum contact occurs in the ABER position • Why posterior capsule contracture produces GIRD and alters humeral head translation • How to measure glenohumeral internal rotation deficit and apply the 20‑25° threshold • The difference between adaptive external‑rotation gain and pathologic total‑arc loss • MRI and arthroscopic features that identify articular‑sided cuff tears and labral fraying • First‑line conservative strategies including posterior capsule stretching and scapular stabilization • Indications for arthroscopic debridement versus repair in progressive disease • How SICK scapula syndrome coexists and influences rehabilitation • The distinction between posterosuperior and anterosuperior internal impingement variants 📌 KEY TAKEAWAYS ✔️ Internal impingement is a normal ABER contact that becomes painful only with posterior capsule tightness. ✔️ GIRD over 20‑25° signals pathologic contracture; total‑arc loss predicts injury better than IR loss alone. ✔️ Conservative posterior capsule stretching and scapular work for 3‑6 months resolves most cases. ✔️ Arthroscopic debridement is reserved for failed conservative care; repair is needed for full‑thickness tears. ✔️ Assess for SICK scapula; addressing scapular dyskinesis is essential to prevent recurrence. ✔️ Differentiate from external (subacromial) impingement and anterosuperior variants by pain position. 👩⚕️ WHO THIS IS FOR This video is designed for orthopaedic trainees, medical students, physiotherapists, and clinicians who manage shoulder injuries, as well as interested patients and athletes seeking to understand the thrower's shoulder. 📚 RELATED TOPICS: Posterior capsule stretching techniques · SICK scapula syndrome · SLAP lesions and labral repair · Rotator cuff articular‑sided tears · External (subacromial) impingement · Humeral retroversion in overhead athletes 🔗 More free orthopaedic teaching at Orthovellum.com — subscribe for weekly videos. 🎨 CREDITS • Original Orthovellum production. ⚠️ DISCLAIMER: Educational only — not individual medical advice. Always consult a qualified clinician for diagnosis and treatment. #internalimpingement #throwersshoulder #GIRD #ABERposition #posteriorscapsule #shoulderpain #rotatorcufftear #labralfray #scapulardyskinesis #sickscapula #orthopaedics #sportsmedicine #physiotherapy #arthroscopy #conservativetreatment