AC joint stabilisation is a surgical procedure to restore the normal position and stability of the acromioclavicular joint following dislocation or chronic instability. It is recommended when ligament disruption is severe enough that the shoulder cannot function reliably without surgical reconstruction of the joint’s stabilising structures.
Dr. Kushalappa Subbiah performs arthroscopic-assisted AC joint stabilisation and ligament reconstruction for patients with high-grade AC joint separations and those with chronic instability that has not responded to conservative treatment.
What is AC Joint Stabilisation?
The acromioclavicular joint is held in its normal position by two sets of ligaments: the acromioclavicular ligaments, which provide horizontal stability, and the coracoclavicular ligaments (the trapezoid and conoid), which provide vertical suspension and prevent the clavicle from riding upward above the acromion. In high-grade AC joint separations (Types IV, V, and VI, and selected Type III injuries), both ligament groups are completely disrupted and the joint cannot be restored without surgical intervention.
AC joint stabilisation aims to anatomically reconstruct these ligaments, restoring the clavicle to its correct position and allowing the shoulder to function normally under load. Modern techniques use tendon graft to reconstruct the coracoclavicular ligaments, which are the primary vertical stabilisers of the joint.
Types of AC Joint Stabilisation
Causes
AC joint injuries most commonly result from a direct fall onto the tip of the shoulder, which is the most common mechanism in contact sport. The impact drives the acromion downward while the clavicle remains in its normal position, tearing the acromioclavicular and coracoclavicular ligaments progressively depending on the force involved.
- A visible or palpable step deformity at the top of the shoulder, where the outer end of the clavicle is elevated above the acromion
- Pain and tenderness directly over the AC joint, which is located at the very top of the shoulder where the clavicle meets the acromion
- Pain that worsens with overhead movements, reaching across the body, and activities that load the shoulder
- Weakness with lifting, pushing, and overhead tasks, particularly noticeable in athletes and manual workers
- A feeling of instability or lack of confidence in the shoulder under load
- In chronic instability: persistent aching pain at the top of the shoulder with activity, even when the acute injury has long settled
- In AC joint arthritis: a grinding or clicking sensation at the joint with shoulder movement, alongside pain that is present at rest and worse at night
Diagnosis
Clinical examination is the first step. Dr. Kushalappa assesses the AC joint for tenderness, step deformity, and instability. The cross-body adduction test, where the arm is brought across the front of the body to compress the AC joint, reproduces pain and confirms AC joint involvement. The AC joint stress test assesses vertical instability by applying downward traction to the arm while observing clavicle displacement.
Plain X-rays of both AC joints in the anteroposterior projection, taken with and without weights held in the hands, are the standard investigation. Comparing the injured and uninjured sides quantifies the degree of clavicle elevation and allows classification of the injury using the Rockwood system. The Zanca view, a specific angled projection centred on the AC joint, provides improved detail of the joint itself.
MRI is used to assess the condition of the coracoclavicular and acromioclavicular ligaments, identify any associated intra-articular shoulder pathology, and evaluate soft tissue quality prior to surgical planning. CT scan is occasionally used in chronic cases to assess AC joint morphology and the coracoid anatomy ahead of ligament reconstruction.
Treatment
Non-Surgical Management
For Type I and Type II AC joint injuries, and many Type III separations in non-athletes, conservative management is the first line of treatment. This involves a sling for 1 to 3 weeks for pain relief, followed by a structured physiotherapy programme focusing on restoring range of motion and rotator cuff and periscapular muscle strength. The majority of low-grade AC joint injuries recover well without surgery, with full return to activity expected within 6 to 12 weeks.
Arthroscopic-Assisted AC Joint Stabilisation and Ligament Reconstruction
For high-grade dislocations (Types IV, V, and VI), selected Type III injuries in high-demand athletes and manual workers, and patients with chronic AC joint instability that has failed conservative management, Dr. Kushalappa performs arthroscopic-assisted coracoclavicular ligament reconstruction. A tendon graft is passed through precisely placed drill tunnels in the clavicle and around the coracoid to anatomically reconstruct the coracoclavicular ligaments and restore the normal position of the clavicle. The acromioclavicular ligaments are repaired simultaneously to restore horizontal stability. Where indicated, a synthetic augmentation device is used alongside the biological graft to provide early strength during the healing period.
Distal Clavicle Resection (where indicated)
When AC joint arthritis is present alongside instability, a small portion of the outer end of the clavicle is resected arthroscopically to eliminate arthritic pain and prevent impingement at the reconstructed joint. This is performed in the same procedure as the ligament reconstruction where appropriate.
Why Choose Dr. Kushalappa Subbiah in Bangalore?
Dr. Kushalappa Subbiah completed a Fellowship in Shoulder Surgery at the Sydney Shoulder Research Institute, where he trained in advanced arthroscopic shoulder procedures including labral repair and reconstruction. He holds the International Olympic Committee (IOC) Diploma in Sports Medicine, and has direct clinical experience managing shoulder injuries in Indian athletes across cricket, swimming, tennis, and contact sports. He is appointed as a Consultant Shoulder Surgeon at NH Hospital, Bangalore.