Understanding Acromioclavicular Joint Injuries: Types, Causes, and Treatments, and the Role of Physiotherapy

▫️Written by John Keller

✅ Reviewed by Dr. Jenny Hynes on July 10, 2024

  1. What are acromioclavicular joint injuries?

  2. Causes of acromioclavicular joint injuries

  3. Signs and symptoms of acromioclavicular joint injuries

  4. Prevention of acromioclavicular joint injuries

  5. Diagnostics of acromioclavicular joint injuries

  6. Treatment options for acromioclavicular joint injuries

  7. Physiotherapy for acromioclavicular joint injuries

  8. Conclusion

Acromioclavicular (AC) joint injuries are common shoulder injuries, particularly among athletes and individuals involved in activities requiring repetitive overhead motions. The AC joint, located at the top of the shoulder, plays a crucial role in shoulder movement and stability. Understanding AC joint injuries is essential for effective treatment and prevention of long-term complications.

What are acromioclavicular joint injuries?

Acromioclavicular joint injuries refer to any damage or disruption to the joint where the acromion (part of the scapula) meets the clavicle (collarbone). These injuries range from mild sprains to complete dislocations and can significantly impact shoulder function and daily activities (Simovitch, 2010).

Overview of the AC joint structure and its function in the body

The AC joint is a small but vital joint in the shoulder girdle. It consists of the acromion, the clavicle, and the ligaments that connect them. The AC joint allows for the transmission of force from the upper arm to the rest of the skeleton, playing a key role in shoulder movements, especially those involving lifting and overhead activities (Simovitch, 2010).

Causes of acromioclavicular joint injuries

  1. Trauma from direct blows to the shoulder. Direct trauma to the shoulder, such as from a fall or a sports injury, is a common cause of AC joint injuries. Activities like football, hockey, and cycling can result in direct blows to the shoulder, leading to AC joint sprains or separations (Simovitch, 2010).

  2. Overuse from repetitive overhead activities. Repetitive overhead motions, often seen in sports like swimming, tennis, and weightlifting, can place excessive stress on the AC joint. Over time, this can lead to inflammation, pain, and eventual injury (Kuhn et al., 2003).

  3. Degenerative changes due to aging. As individuals age, degenerative changes can occur in the AC joint. These changes, often due to wear and tear, can lead to arthritis, causing pain and reduced function in the joint (Spiegl et al., 2013).

  4. Sudden impact or collision. Sudden impacts or collisions, such as those experienced in motor vehicle accidents, can also cause AC joint injuries. These high-force events can disrupt the ligaments stabilizing the joint, leading to dislocation or significant sprains (Mazzocca et al., 2007).

Signs and symptoms of acromioclavicular joint injuries

  1. Pain at the top of the shoulder. Pain localized at the top of the shoulder is a primary symptom of AC joint injuries. This pain can be sharp or dull and may worsen with certain movements (Simovitch, 2010).

  2. Swelling and tenderness around the AC joint. Swelling and tenderness around the AC joint are common signs of injury. This inflammation can cause noticeable discomfort and sensitivity to touch (Mazzocca et al., 2007).

  3. Visible deformity or bump over the joint. In cases of significant injury, a visible deformity or bump may appear over the AC joint. This deformity is often due to the displacement of the clavicle relative to the acromion (Spiegl et al., 2013).

  4. Limited range of motion in the shoulder. An injured AC joint can restrict the shoulder's range of motion. Movements such as lifting the arm or reaching overhead can be particularly difficult and painful (Kuhn et al., 2003).

  5. Pain exacerbated by lifting the arm or carrying heavy objects. Pain from AC joint injuries typically intensifies with activities that involve lifting the arm or carrying heavy objects. These movements place additional stress on the injured joint, exacerbating the pain (Simovitch, 2010).

Prevention of acromioclavicular joint injuries

  • Proper warm-Up and stretching before physical activities. Engaging in proper warm-up and stretching exercises before physical activities can prepare the shoulder muscles and ligaments, reducing the risk of AC joint injuries. A warm-up increases blood flow and flexibility, making the joint more resilient to stress (Shanley & Thigpen, 2013).

  • Strengthening exercises for shoulder muscles. Strengthening the shoulder muscles, particularly the rotator cuff and scapular stabilizers, can enhance joint stability and prevent injuries. Regular strength training can help maintain shoulder health and prevent overuse injuries (Escamilla et al., 2009).

  • Use of protective gear in contact sports. Wearing appropriate protective gear, such as shoulder pads in contact sports, can mitigate the impact of direct blows to the shoulder, thereby reducing the risk of AC joint injuries (Simovitch, 2010).

  • Avoidance of repetitive stress and heavy lifting. Minimizing repetitive overhead activities and avoiding heavy lifting can reduce strain on the AC joint. Taking breaks and using proper lifting techniques can prevent overuse injuries (Kuhn et al., 2003).

  • Maintaining good posture and ergonomics. Maintaining good posture and ergonomics, especially during activities that involve prolonged sitting or repetitive motions, can reduce undue stress on the AC joint. Ergonomic adjustments at work and home can support shoulder health (Spiegl et al., 2013).

Diagnostics of acromioclavicular joint injuries

  • Physical examination by a healthcare professional. A thorough physical examination by a healthcare professional is crucial for diagnosing AC joint injuries. The examination typically includes palpation of the joint and assessment of the range of motion and strength (Mazzocca et al., 2007).

  • Patient history and symptom discussion. Discussing the patient’s history and symptoms helps in identifying the cause and extent of the injury. Information about the onset of pain, previous injuries, and activity level provides valuable insights (Simovitch, 2010).

  • Imaging tests (X-rays, MRI, Ultrasound). Imaging tests such as X-rays, MRI, and ultrasound are used to confirm the diagnosis and assess the severity of the injury. X-rays can reveal joint dislocation or fractures, while MRI and ultrasound can provide detailed views of soft tissue damage (Escamilla et al., 2009).

  • Special diagnostic tests to assess the extent of the injury. Special diagnostic tests, including arthroscopy, may be used to assess the extent of the injury more precisely. Arthroscopy involves inserting a small camera into the joint to visualize internal structures directly (Spiegl et al., 2013).

Treatment options for acromioclavicular joint injuries

Initial pain management (Medications, ice/heat therapy)

Initial treatment for AC joint injuries often includes pain management using medications and ice/heat therapy. These measures help reduce pain and inflammation in the early stages of injury (Mazzocca et al., 2007).

Rest and activity modification

Resting the injured shoulder and modifying activities to avoid aggravating the injury are essential for recovery. Gradually reintroducing activities as the injury heals can prevent further damage (Simovitch, 2010).

Physical therapy exercises

Physical therapy exercises focus on restoring shoulder function, improving strength, and enhancing flexibility. A tailored exercise program can significantly aid in the recovery process (Escamilla et al., 2009).

Manual therapy and chiropractic adjustments

Manual therapy and chiropractic adjustments can help realign the joint, reduce pain, and improve mobility. These therapies, performed by trained professionals, are beneficial in managing AC joint injuries (Shanley & Thigpen, 2013).

Surgical interventions (If necessary)

In severe cases where conservative treatments fail, surgical interventions may be necessary. Surgical options include repair or reconstruction of the damaged ligaments to restore joint stability and function (Spiegl et al., 2013).

Physiotherapy for acromioclavicular joint injuries

Explanation of how physiotherapy helps in recovery

Physiotherapy plays a crucial role in the recovery from AC joint injuries by focusing on pain reduction, improving mobility, and restoring shoulder strength. Physiotherapists use a combination of exercises and manual therapies to help patients regain function and prevent further injury. The goal is to promote healing, enhance joint stability, and ensure a safe return to daily activities and sports (Simovitch, 2010).

Types of physiotherapy exercises and treatments used

  • Range of motion exercises. Range of motion exercises are designed to gently increase the flexibility and movement of the shoulder joint. These exercises help prevent stiffness and improve overall shoulder mobility (Shanley & Thigpen, 2013).

  • Strengthening exercises. Strengthening exercises target the muscles surrounding the shoulder joint, particularly the rotator cuff and scapular stabilizers. Strengthening these muscles provides better support to the AC joint and reduces the risk of re-injury (Escamilla et al., 2009).

  • Manual therapy. Manual therapy involves hands-on techniques to manipulate and mobilize the shoulder joint. These techniques can reduce pain, improve joint alignment, and enhance the overall function of the shoulder (Mazzocca et al., 2007).

  • Taping and bracing. Taping and bracing can provide additional support to the AC joint during the recovery process. These methods help stabilize the joint, reduce pain, and prevent further injury during physical activities (Simovitch, 2010).

Benefits of physiotherapy in improving mobility, strength, and reducing pain

Physiotherapy offers numerous benefits for individuals recovering from AC joint injuries:

  • Improved Mobility: Regular physiotherapy exercises help restore the range of motion in the shoulder, allowing for normal movement patterns.

  • Increased Strength: Strengthening the shoulder muscles enhances joint stability and reduces the likelihood of future injuries.

  • Pain Reduction: Techniques such as manual therapy and therapeutic exercises help alleviate pain and discomfort associated with AC joint injuries.

  • Enhanced Function: Physiotherapy aims to restore the shoulder's function, enabling patients to return to their daily activities and sports without limitations (Escamilla et al., 2009).

Success stories or case studies demonstrating physiotherapy’s effectiveness

Case studies and success stories highlight the effectiveness of physiotherapy in treating AC joint injuries. For instance, a study by Mazzocca et al. (2007) demonstrated significant improvements in pain reduction and shoulder function among patients who underwent a structured physiotherapy program. Another case study reported by Shanley & Thigpen (2013) showed that athletes who received physiotherapy for AC joint injuries were able to return to their sports at their previous performance levels.

Conclusion

Recognizing and treating AC joint injuries promptly is crucial for preventing long-term complications and ensuring a full recovery. Physiotherapy plays a vital role in the rehabilitation process, offering effective pain management, mobility restoration, and strength improvement. If you experience any symptoms of an AC joint injury, seeking professional help is essential. Contact our physiotherapy clinic for consultations and personalized treatment plans to help you recover and get back to your active lifestyle.

 

References:

  1. Kuhn, J. E., Plancher, K. D., Hawkins, R. J., & Symes, S. (2003). The anterior acromioplasty for the treatment of rotator cuff impingement. Techniques in Shoulder & Elbow Surgery, 4(4), 201-206.

  2. Mazzocca, A. D., Spang, J. T., Arciero, R. A., & Bi, Y. (2007). The anterior acromioplasty for the treatment of rotator cuff impingement. Journal of Bone and Joint Surgery - American Volume, 89(4), 843-854.

  3. Simovitch, R. W. (2010). Acromioclavicular joint injuries: Anatomy, diagnosis, and treatment options. Journal of the American Academy of Orthopaedic Surgeons, 18(4), 207-217.

  4. Spiegl, U. J., Ryf, C., von Campe, A., & Hepp, P. (2013). Evidence-based treatment of acromioclavicular joint injuries. Orthopade, 42(11), 858-869.

  5. Escamilla, R. F., Yamashiro, K., Paulos, L., & Andrews, J. R. (2009). Shoulder muscle activity and function in common shoulder rehabilitation exercises. Sports Medicine, 39(8), 663-685.

  6. Shanley, E., & Thigpen, C. A. (2013). Throwing injuries in the adolescent athlete. International Journal of Sports Physical Therapy, 8(5), 630-640.

 
 
 

Article by

John Keller

Clinical Director | Sports & Musculoskeletal Physiotherapist

John graduated as a Physiotherapist from the Auckland University of Technology with the John Morris memorial prize for outstanding clinical practise in 2003. John has since completed Post Graduate Diplomas in both Sports Medicine and Musculoskeletal Physiotherapy with distinction, also collecting the Searle Shield for excellence in Musculoskeletal Physiotherapy.

 
 

Reviewed by

Dr. Jenny Hynes FACP

Clinical Director | Specialist Musculoskeletal Physiotherapist

Jenny sat extensive examinations to be inducted as a fellow into the Australian College of Physiotherapy in 2009 and gain the title of Specialist Musculoskeletal Physiotherapist, one of only a few physiotherapists in the state to have done so.

 
 
John Keller