A 76-year-old female patient had mild soreness in her right shoulder joint for two to three years, but she was able to lift the shoulder joint and her daily life was not affected much, except that she had slightly less strength when lifting. She went to the hospital for an MRI and the report said there was a huge rotator cuff injury. One day, 3 months later, the patient suddenly couldn’t lift his shoulder and underwent surgery. After the surgery, the doctor said that the rotator cuff injury was irreparable and the patient had to undergo a joint debridement surgery. After the surgery, the joint pain was not so severe, but I was still unable to lift my arm and my daily life was obviously affected. What exactly is a non-repairable rotator cuff injury? What should I do if my rotator cuff injury is irreparable? We need to start with the anatomy and function of the rotator cuff. 1. What is rotator cuff? The shoulder joint is composed of the scapula, humerus and the soft tissue structures that connect the two. The rotator cuff is a part of these connecting tissues, which emanates from the scapula and wraps around and attaches to the head of the humerus like a cuff. The rotator cuff is divided into three groups: anterior rotator cuff (subscapularis), superior rotator cuff (supraspinatus) and posterior rotator cuff (infraspinatus and teres minor). Each group of rotator cuff includes a medial muscular portion and a lateral tendon portion. 2. What is the function of the rotator cuff? The basic function of the rotator cuff is to “hold” the humeral head, that is, to hold the humeral head firmly in the plane of the scapular glenoid during the upper arm lift, forming a fulcrum so that the deltoid can function to lift the arm. If the rotator cuff is not functional and cannot “hold” the humeral head, when trying to lift the shoulder, because of the lack of a fulcrum, the contraction of the deltoid muscle can only pull the humerus upward, which means that it can only shrug the shoulder, but not lift the arm. In addition, the rotator cuff itself also has a certain function of lifting and rotating the arm. 3. Why do rotator cuff injuries occur? Rotator cuff injury mainly occurs in two cases: one is the degenerative rotator cuff injury in the elderly. As people age, various tissues degenerate and the tendon part of the rotator cuff becomes brittle and the blood supply becomes poor, which, combined with chronic wear and tear, can lead to rupture. Most rotator cuff injuries in younger people are caused by trauma. Of course, if an older person has a fall or other trauma, the rotator cuff is more likely to rupture. 4. Do all rotator cuff injuries require surgery? Rotator cuff injuries are common in the elderly. One study found that about half of people over the age of 60 have rotator cuff injuries of varying degrees, but these people do not feel any shoulder discomfort or dysfunction. This suggests, on the one hand, that people can live with an incomplete rotator cuff without discomfort and, on the other hand, that rotator cuff injuries do not necessarily require surgical treatment afterwards. Each rotator cuff has a certain width and thickness, and if only a portion of a rotator cuff is broken, it does not necessarily affect its overall function. Follow-up of patients with rotator cuff repair has also shown that even though some patients have only healed 60 to 70 percent of their rotator cuffs after repair, the shoulder joint function has recovered well. People with rotator cuff injuries can be divided into those with functional rotator cuff injuries and those without functional rotator cuff injuries, depending on the functional status of the shoulder joint. Functional rotator cuff injury means that despite having rotator cuff injury, the shoulder joint lifting function is basically normal, which is further divided into two categories based on symptoms: painless and painful. People with a painless functional rotator cuff injury cannot be called patients because these people can live a normal life despite having an incomplete or imperfect rotator cuff; they are imperfectly normal people. People with a painful functional rotator cuff injury are the ones who can be considered patients. These people have pain that affects their quality of life to some extent because they have pain, even though the shoulder joint is functioning okay. A true patient is someone with a non-functional rotator cuff injury because these people cannot lift the shoulder joint and it affects their normal life. Painful nonfunctional rotator cuff injuries are the most serious because the patient not only has limited function, but also has more severe pain in the shoulder joint during activity or at rest, which has the greatest impact on daily life. Painless non-functional rotator cuff injury means that there is no discomfort in the shoulder joint, but the patient cannot lift it, which also affects eating, brushing teeth and combing hair. This particular type of rotator cuff injury is also known as pseudo-paralysis, which means that the patient’s shoulder looks like he or she has had a stroke and is paralyzed, and can be lifted with the good hand to help the bad hand, but the bad hand falls off when the good hand is released. If there is a rotator cuff injury, but the shoulder joint is functioning normally and there is no pain, which is a painless functional rotator cuff injury, then surgery is not needed. If it is a painful functional rotator cuff injury, the first step can be to take conservative treatment to stop the pain. If conservative treatment is not effective for some patients, surgery may be considered. For painful but functional rotator cuff injuries, the purpose of surgery is not to repair the rotator cuff, but to remove the pain-causing factor. In rotator cuff injuries, that is, when there is a rupture in the rotator cuff, the rupture itself does not produce pain. The cause of the pain is mostly other factors, such as compression of the rotator cuff edge, impingement of the rotator cuff, calcification of the rostral shoulder ligament, subacromial bursitis, biceps tendonitis, acromioclavicular arthritis, etc. By removing these pain-causing factors during surgery, the overall function of the shoulder joint will be significantly improved even without repairing the rotator cuff. Of course, the surgeon will not leave the torn rotator cuff unattended during surgery and will repair it accordingly. However, in the case of functional rotator cuff tears, it is not advisable to make a major effort to repair the rotator cuff, otherwise the rotator cuff that was functional may become non-functional due to excessive changes in the anatomy, which may outweigh the losses. Patients with non-functional rotator cuff injuries will require surgery if they want to improve function. Generally speaking, patients with painful non-functional rotator cuff injuries benefit the most from surgery, because the non-functional rotator cuff in these patients is not necessarily caused by a complete rotator cuff rupture, but rather by severe pain that inhibits the residual function of the defective rotator cuff. Of course, repair of the rotator cuff at the time of surgery is also a guarantee of restoration of shoulder function. For this type of patient, pain relief surgery is as important as rotator cuff repair surgery. Painless non-functional rotator cuff injuries are the biggest test for the surgeon. This is because the reason these patients have a nonfunctional rotator cuff is indeed caused by a rotator cuff rupture. To have reliable restoration of shoulder function, it is entirely dependent on effective surgical treatment to reconstruct rotator cuff function. 5. What is an irreparable rotator cuff tear? The rotator cuff is the muscular portion on the side near the medial side, the scapula, and the tendonous portion on the side near the lateral side, the humeral head. Rotator cuff tears rarely occur in the muscular portion and in the vast majority of cases occur in the tendinous portion. In younger patients, a rotator cuff tear caused by trauma is usually a tear, and no matter how long the tear is, repairing it is not a problem. In older patients, rotator cuff tears are often a hole in the rotator cuff. Not only are the tendon fibers broken, but there is also resorption and deficiency of the tendon tissue, just like a large hole in a broken sack. This kind of hole often cannot be repaired by a few stitches alone. When a rotator cuff tear cannot be repaired, it is called an irreparable rotator cuff tear. There is also a special kind of tear that cannot be repaired, that is, the rotator cuff is split at the junction of tendon and muscle, because the muscle side is too brittle to hang sutures, so it cannot be repaired. 6. What should I do if I have a rotator cuff tear that cannot be repaired? In the anterior, superior and posterior rotator cuffs, there are three groups of rotator cuffs that are completely torn or irreparable and have different effects on the function of the shoulder joint. The anterior group of rotator cuff refers to the subscapularis, and complete non-function will affect the internal rotation and back hook of the arm. The affected side of the hand cannot feel the waist, has difficulty rubbing the back by itself, and female patients have difficulty tying the chest belt. Anterior group rotator cuff tears require rotator cuff reconstruction if they are not repairable or local tendon transfer on the anterior side of the shoulder joint. The posterior rotator cuff refers to the infraspinatus and teres minor, which are mainly responsible for external rotation of the shoulder joint. A complete rupture to the point of irreparability will affect the patient’s movements of eating, brushing teeth and combing hair. For irreparable tears of the posterior rotator cuff, a posterior back tendon transfer (latissimus dorsi transfer) is required. The upper rotator cuff refers to the supraspinatus muscle, which is primarily responsible for shoulder elevation. When the upper rotator cuff is completely ruptured to the point of being irreparable, measures need to be taken on a case-by-case basis. Unlike anterior and posterior rotator cuff tears, a complete rupture of the superior rotator cuff does not necessarily result in loss of function of the shoulder joint, even if it cannot be repaired. The above classification of function after rotator cuff injury refers to upper rotator cuff injuries. In some patients, the rotator cuff has a huge tear and is not repairable, but the shoulder joint function is basically normal, so surgical treatment is not required. There are two main reasons why the upper rotator cuff is completely non-functional but the shoulder joint is functional: one is that the anterior and posterior rotator cuffs are partially compensating for the upper rotator cuff, so even if one rotator cuff is missing, the other two groups can still pull the humeral head and play a pivot role; the other is that the anterior and posterior rotator cuffs are not compensating for the humeral head and the humeral head is displaced upward. However, the humeral head then rested against the rostral arch above, creating a new fulcrum here in the rostral arch, and it worked, so the shoulder could still be lifted. Unfortunately, there are many cases where the upper rotator cuff does not function causing the humeral head to shift upward against the rostral arch, but fewer cases where a useful fulcrum is formed and the shoulder can be lifted. For rotator cuff injuries where a new useful fulcrum is formed, the most common mistake is to blindly operate on the acromioplasty, destroying the rostral arch and ending up with an arm that cannot be lifted. Nonfunctional massive rotator cuff injuries, although irreparable, require surgical attempts in principle. Broadly speaking, there are three approaches. The first is to do a partial repair. There are a small number of patients with pseudo-paralysis who can lift their arm even though only 1/4 or 1/3 of the connection between the rotator cuff and the humerus has been restored by partial rotator cuff repair. This is usually due to partial restoration of upper rotator cuff function combined with functional compensation of the anterior and posterior rotator cuffs. The second method is rotator cuff reconstruction. This involves taking tendons from other parts of the body (usually the ipsilateral calf or thigh) and connecting the rotator cuff rupture with a tendon strip from medial to lateral, so that the rotator cuff rupture can function even though it is not airtightly repaired. Currently, the use of tendon strips to reconstruct the rotator cuff is technically mature and usually takes 1.5-2 hours. However, the success rate of this procedure is not yet too high, and only about 80% of patients with pseudoparalysis are able to regain function through this procedure. The advantage of this procedure is that it is very inexpensive. The latest rotator cuff reconstruction technique uses both tendon strips and fascial patches, which means that the rotator cuff hole is bridged from the inside out using the tendon strips as the main beam, and then the tendon strips are covered with patches to make the rotator cuff hole airtight. This technique is a little more complicated and takes 2-2.5 hours to perform, but the overall result is better. The third technique is to perform a shoulder joint replacement. This is a special type of replacement called a reverse shoulder replacement. With this procedure, a new fulcrum is artificially created and the center of rotation of the shoulder joint is moved inward so that the deltoid can function to lift the arm even without the upper rotator cuff, similar in principle to the humeral head moving against the rostral arch to form a new fulcrum. Currently, reverse shoulder replacement is more effective than rotator cuff reconstruction, but the cost of 14 or 15 materials is a significant burden for the patient. Therefore, for non-repairable non-functional rotator cuff injuries, we recommend rotator cuff reconstruction first, as it is much less expensive. If the patient is unlucky and is not in the 80% success rate, i.e., the rotator cuff reconstruction fails, then a costly reverse shoulder replacement can be considered. The female patient above ended up having a rotator cuff reconstruction. It was a simple tendon strip reconstruction, where a tendon was taken from the ankle and the hole in the rotator cuff was repaired. In the end, the patient was fortunate enough to regain function.