AC Joint Arthritis: Exercises to Avoid, Modifications, and Management Principles

What exercises should you avoid with AC joint arthritis?

When managing AC joint arthritis, it's crucial to avoid exercises that place direct compressive, shear, or excessive tensile stress on the acromioclavicular joint, particularly those involving overhead movements, heavy pressing, or deep dipping, to minimize pain and prevent further irritation.

Understanding AC Joint Arthritis

The acromioclavicular (AC) joint is a small but critical joint located at the top of the shoulder, where the clavicle (collarbone) meets the acromion (part of the shoulder blade). Like other joints, it's susceptible to osteoarthritis, a degenerative condition where the protective cartilage on the ends of the bones wears down over time. This can lead to bone-on-bone friction, inflammation, and pain.

Symptoms of AC joint arthritis typically include:

• Localized pain at the top of the shoulder, often radiating to the neck or deltoid.
• Pain aggravated by specific movements, especially reaching across the body, overhead lifting, or sleeping on the affected side.
• Clicking, grinding, or popping sensations within the joint.
• Tenderness to touch directly over the AC joint.
• Reduced range of motion in the shoulder, particularly into horizontal adduction (reaching across the body) or end-range elevation.

Biomechanics of AC Joint Pain

To understand which exercises to avoid, it's essential to grasp how certain movements stress the AC joint. The AC joint is relatively small and designed for subtle movements that allow the scapula to rotate and move in conjunction with the humerus. Excessive forces, especially those that:

• Compress the joint: Pushing the clavicle and acromion together (e.g., heavy overhead loads, deep dips).
• Shear the joint: Causing the bones to slide past each other (e.g., heavy bench pressing, especially with a wide grip).
• Place excessive tensile stress: Pulling the joint apart (less common in typical resistance training but can occur with certain hanging or pulling movements if uncontrolled).
• Force end-range horizontal adduction or elevation with internal rotation: These positions can narrow the subacromial space or directly impinge the AC joint.

These forces, particularly under load, can exacerbate the wear and tear on the already compromised cartilage, leading to increased pain and inflammation.

Exercises to Avoid

Based on the biomechanical principles and common triggers for AC joint pain, the following exercises should generally be avoided or approached with extreme caution and modifications:

• Overhead Presses (Barbell, Dumbbell, Machine):
  • Why avoid: These exercises involve lifting a load directly overhead, which creates significant compressive forces through the shoulder girdle, including the AC joint, especially at the end range of motion. The constant pressure can aggravate arthritic changes.
• Upright Rows:
  • Why avoid: This exercise combines shoulder elevation with internal rotation and abduction, a motion that can create impingement at the AC joint and subacromial space. The high elbow position and internal rotation place undue stress on the joint.
• Heavy Bench Presses (Especially Flat and Incline Barbell):
  • Why avoid: While not directly overhead, heavy pressing, particularly with a wide grip, can create significant shear forces across the AC joint, especially at the bottom of the movement as the humerus horizontally adducts and the scapula retracts. This can grind the joint surfaces.
• Dips (Parallel Bar Dips):
  • Why avoid: Deep dips place the shoulder in an extended, internally rotated, and abducted position under bodyweight load. This creates extreme compressive forces on the AC joint at the bottom of the movement as the acromion and clavicle are pushed together.
• Push-ups (Deep Range):
  • Why avoid: Similar to dips, performing push-ups to a deep range of motion, especially with hands wide, can increase the compressive and shear forces on the AC joint.
• Pec Deck Flyes or Machine Chest Flyes (Extreme Range):
  • Why avoid: While often thought of as a chest exercise, taking the arms into extreme horizontal adduction (crossing the midline of the body) under resistance can place excessive stress and compression on the AC joint.
• Lateral Raises (Especially with Heavy Weights or Poor Form):
  • Why avoid: While often beneficial for deltoid development, performing lateral raises with excessive weight, or with the thumbs pointing down (internal rotation), can contribute to impingement and direct AC joint compression, particularly at the top of the movement.
• Any Exercise Causing Pain:
  • Why avoid: This is the paramount rule. If an exercise elicits or exacerbates pain in your AC joint, regardless of whether it's on this list, it should be avoided or modified immediately. Pain is your body's signal that something is wrong.

Modifications and Alternatives

Rather than completely abandoning all upper body training, focus on modifications that reduce stress on the AC joint:

• Reduce Range of Motion: Stop exercises before the point of pain or where you feel excessive joint compression.
• Adjust Grip Width: For presses, a narrower, neutral, or slightly supinated (underhand) grip can sometimes be less irritating.
• Change Angles: Opt for incline presses over flat if it feels better, or use dumbbells to allow for a more natural range of motion compared to barbells.
• Focus on Scapular Stability: Prioritize exercises that strengthen the muscles stabilizing the scapula (rhomboids, serratus anterior, lower trapezius) and rotator cuff muscles. This improves overall shoulder mechanics and reduces AC joint strain.
• Utilize Neutral Grip: Dumbbells or specific handles (e.g., Swiss bar) that allow a neutral grip (palms facing each other) can be less stressful for many pressing movements.

General Principles for Managing AC Joint Arthritis

Beyond avoiding problematic exercises, consider these broader principles:

• Listen to Your Body: This is non-negotiable. Pain is a warning sign.
• Prioritize Pain-Free Movement: Focus on exercises you can perform without any pain in the AC joint.
• Warm-Up Thoroughly: Adequate warm-up increases blood flow and joint lubrication, potentially reducing stiffness.
• Focus on Shoulder Stability and Mobility: A balanced program that addresses both the stability of the scapula and the mobility of the glenohumeral (ball-and-socket) joint can alleviate stress on the AC joint.
• Gradual Progression: When introducing new exercises or increasing intensity, do so very slowly and monitor your symptoms.
• Consider Anti-Inflammatory Strategies: Ice application after exercise can help manage inflammation.

When to Seek Professional Guidance

While this guide provides general advice, AC joint arthritis management is highly individual. It is strongly recommended to consult with a qualified healthcare professional, such as a physical therapist, orthopedic surgeon, or sports medicine physician, especially if:

• Your pain is persistent or worsening.
• You experience significant functional limitations.
• You are unsure how to modify exercises safely.
• You are considering steroid injections or surgical options.

A professional can provide an accurate diagnosis, guide you through a personalized rehabilitation program, and help you return to activity safely while protecting your AC joint.