Internal Impingement Shoulder Injuries Overview

Internal shoulder impingement is a condition that primarily affects throwing athletes.

This condition affects the following structures:

Woman throwing tennis ball in the air getting ready to serve
PhotoAlto / Sandro Di Carlo Darsa / Getty Images

The problem is caused by pinching between the tuberosity (top of the humerus) against the labrum. Internal shoulder impingement inhibits internal rotation, which is the ability to fully rotate the shoulder inward.

Signs of Internal Impingement

The most common signs of this problem include:

  • Pain when throwing in overhead sports (such as tennis serves)
  • Tenderness on the front of the shoulder (pectoralis minor tendon/coracoid process)
  • Tenderness around the scapula and the posterior shoulder capsule

You may notice that you have difficulty reaching up high to the back on your affected side in comparison to your unaffected side. 

Typically, shoulder mobility is slightly abnormal during a physical examination. Specifically, with internal shoulder impingement, you might have more external rotation than expected (which is common in throwing athletes) and slightly decreased internal rotation. 

And you can have subtle instability of your shoulder joint. The instability of the shoulder is thought to be a key component of why internal impingement develops.

Diagnostic tests may include a shoulder X-ray, which is usually normal. An MRI generally shows some bone bruising (edema) at the ball-and-socket shoulder joint, a partial thickness tear of the rotator cuff, and/or damage to the labrum (although not typically a detachment of the labrum).

Treatment Options

Treatment usually starts with noninvasive strategies to address the problems in shoulder mechanics. The focus of treatment is to regain normal shoulder rotation and to improve the movement of the scapula throughout the shoulder range of motion.

A physical therapist or trainer can work with you to reach this goal. Conservative management helps the vast majority of the time, even for high-level athletes.

If you don’t improve despite a focused effort on therapy, you might consider having arthroscopic shoulder surgery. Generally, surgery is done to repair damage to the rotator cuff or the labrum, and also to address any subtle instability of the shoulder joint that may be contributing to the problem.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Corpus KT, Camp CL, Dines DM, Altchek DW, Dines JS. Evaluation and treatment of internal impingement of the shoulder in overhead athletes. World J Orthop. 2016;7(12):776–784. doi:10.5312/wjo.v7.i12.776

  2. Stone MA, Jalali O, Alluri RK, et al. Nonoperative treatment for injuries to the in-season throwing shoulder: a current concepts review with clinical commentary. Int J Sports Phys Ther. 2018;13(2):306-320. PMID: 30090688

By Jonathan Cluett, MD
Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams.