Definition of subacromial impingement syndrome:

The subacromial impingement syndrome is a shoulder pathology causing pain at the superior and anterior aspects of the shoulder tip with a catching feeling reproduced between 70° and 90° abduction, in particular. Subacromial impingement is tendino-bursitis (tendonitis) of the cuff muscle’s tendons which are compressed between the upper end of the humerus (trochiter and humeral head) on one side and the acromion and the coracoacromial ligament on the other side.

Video of subacromial impingement treatment:

Arthroscopic shoulder surgery video showing an operation for subacromial impingement / Toulouse specialist

Anatomy and pathology of subacromial impingement syndrome:

Anatomically, this shoulder pathology is tendonitis of the rotator cuff, specifically of the supraspinatus tendon, with inflammation of the subacromial bursa. This shoulder tendonitis, called impingement, is more likely when the subacromial space is narrowed by three distinct anatomic structures:

  • the acromion, that can be abnormally curved – called a hooked acromion
  • the coracoacromial ligament that can calcify with age
  • the acromioclavicular joint that can be thickened by osteoarthritis.

Arthroscopic shoulder surgery for subacromial impingement, preoperative x-rayArthroscopic shoulder surgery for subacromial impingement syndrome: preoperative CT arthrography: pre-acromial bone, Toulouse


  • When shoulder calcification is found, the calcified growths contribute both to shoulder pain and subacromial impingement.
  • Another frequent factor of subacromial impingement is the existence of a morphological anomaly named os acromiale. Os acromiale is defective fusion of the acromion’s growth cartilages; when os acromiale is of pre-acromial type or meso-acromial type, it narrows the subacromial space and contributes to subacromial impingement syndrome.

Arthroscopic surgical treatment of the subacromial impingement syndrome:

In this shoulder pathology, when the pain does not subside despite medical treatment combining slow-release corticosteroid injections in the shoulder and shoulder rehabilitation based on strengthening exercises for the shoulder’s depressor muscles and accessory depressor muscles, arthroscopic surgery must be considered.
This specialized surgery is performed on an outpatient or inpatient basis under general or regional anaesthesia.
In this procedure, the patient is in the dorsal decubitus position, four 5-mm incisions are required to perform this arthroscopic procedure.

Shoulder arthroscopy, operative beach chair positioning, Toulouse

In this shoulder surgery, the arthroscopic procedure consists in removing the anatomic factors of pain and impingement and enlarging the shoulder's subacromial space available for the tendons of the rotator cuff, especially for the supraspinatus.

1 – The first stage of the procedure consists in exploring the shoulder’s glenohumeral articular space; the assessment focuses on the extent of inflammation of the rotator interval and biceps tendon, rotator cuff continuity and on the condition of the shoulder cartilage. When the biceps’ tendon is inflammatory, it can be removed from the gleno-humeral articular space so that it stays attached to the humerus only; this is called a biceps tenotomy-tenodesis at the shoulder.

Arthroscopic shoulder surgery for subacromial impingement, biceps inflammation, ToulouseArthroscopic shoulder surgery for subacromial impingement syndrome: biceps tenotomy-tenodesis, Toulouse

2 – The second stage in this shoulder surgery takes place in the subacromial space and begins with a resection of the inflammatory subacromial bursa, first with a viper and then with a shaver; this is called shoulder bursectomy. The acromiocoracoid 

Arthroscopic shoulder surgery for subacromial impingement, bursectomy with shaver, ToulouseArthroscopic shoulder surgery for subacromial impingement syndrome: resection of calcified acromio-coracoid ligament, Toulouse

Once the underside of the acromion is fully exposed, it can be “planed" by shaving away 5 mm of bone using a bur, making sure resection is smooth: this is called shoulder acromioplasty.

Arthroscopic shoulder surgery for subacromial impingement, acromioplasty using a bur

Finally, in the last stage of this arthroscopic shoulder surgery, the acromioclavicular joint can be “cleaned” on an individual basis by a one-centimetre deep resection of the clavicle’s lateral extremity.

Arthroscopic shoulder surgery for subacromial impingement, an osteoarthritic clavicle exposed, ToulouseArthroscopic shoulder surgery for subacromial impingement syndrome, 1-cm lateral clavicle resection, Toulouse

Four subacromial decompression procedures are thus performed on the shoulder: surgical resection of the subacromial bursa, resection of the acromiocoracoid ligament, acromioplasty and freshening of the acromioclavicular joint. Additional calcification and/or os acromiale removal procedures can be carried out on an individual basis.
Hemostasis can be performed on the bone surfaces at the end of the operation.
The surgical incisions will be closed with absorbable sutures.

Arthroscopic shoulder surgery for subacromial impingement syndrome, post-operative incisions closed with absorbable suture, ToulouseArthroscopic shoulder surgery for subacromial impingement, post-operative immobilization, Toulouse


Recovery and recuperation after subacromial impingement surgery

After arthroscopic surgery, non-strict shoulder immobilization will be suggested for 2 weeks; it can be removed on request depending on how much pain is felt. Specialized shoulder rehabilitation must be started immediately after surgery. After surgery, most daily activities can resume after 3 to 5 weeks and forceful activities involving the shoulder after 4 to 6 months. Driving often resumes toward the end of the third postoperative week. Shoulder recovery and maximum recuperation spread over 4 to 6 weeks after surgery.

After this shoulder surgery, sick leave duration depends on the occupation; one month at least for office work and 3 to 4 months for more physical work.

Arthroscopic shoulder surgery for subacromial impingement, intensive sport resumes after 4 months.