[Column] A Paradigm Shift in Shoulder Surgery: From the Era of Stitching to the Era of Regeneration

Shoulder pain is often mistaken for simple muscle soreness, but in reality it can have many different causes, ranging from inflammation around the joint, calcific tendinitis, frozen shoulder, and partial tears of the rotator cuff to complete tears. Among these, this article will focus on the rotator cuff, which is responsible for shoulder movement.

Kim Mingyu, Chief of Orthopedics, Eseumji Yonsei Hospital.

The rotator cuff is made up of four muscles that connect the shoulder and arm: the subscapularis, supraspinatus, infraspinatus, and teres minor. These muscles cover the shoulder joint and play a crucial role in arm rotation and in maintaining joint stability. However, as we age, blood flow to the tendons decreases, and the elasticity and strength of the tissue gradually weaken, so even minor injuries no longer heal on their own and remain. When such microscopic damage is repeated and accumulates, the tendon eventually wears down or tears, and in severe cases this progresses to a complete tear. At that stage, not only does pain occur, but arm strength decreases and movement becomes restricted, making even everyday actions such as buttoning clothes or washing hair difficult.

If a partial tear of the rotator cuff is not treated at the appropriate time, it is highly likely to progress to a complete tear. Once a complete tear has occurred and the tendon has fully detached from the bone, the tendon rolls back over time and becomes difficult to reattach, so surgical repair should be performed as early as possible. To prevent this progression from partial to complete tear, the use of collagen injection therapy is increasing. Collagen injection therapy is attracting attention as a non-surgical treatment method that precisely injects a high-concentration collagen solution into the damaged rotator cuff area under ultrasound or arthroscopic guidance, thereby supplementing collagen, the key structural component of the tendon, and promoting cell regeneration.

Over the past one to two years, bioinductive collagen patches have drawn attention as a new treatment method that can prevent partial tears from progressing to complete tears and reduce re-tear after surgery. In cases where pain persists despite repeated injections, where partial tears are confirmed on MRI, and in patients who are anxious about the possibility of "tearing again," collagen patch treatment can be a powerful alternative.

Collagen patches help prevent partial (incomplete) tears from worsening into complete tears, and they are also effective in subacromial impingement syndrome, in which the acromion bone, which serves as the roof of the shoulder joint, becomes elongated or protrudes and repeatedly impinges on the rotator cuff tendon. In this condition, where the rotator cuff tendon located between the acromion and the head of the humerus is damaged by compression, combining acromioplasty, which shaves down the protruding acromion, with coverage of the damaged tendon using a collagen patch produces a strong synergistic effect.

Collagen patches promote tendon regeneration while suppressing additional wear and tear and the progression of tears caused by impingement, helping the tendon remain strong for a longer period. They are also effective in reducing the risk of re-tear after surgical repair of complete tears. In particular, when the tear is detected late and has become large, collagen patches are used to compensate for the high re-tear rates associated with conventional repair techniques.

The procedure is performed arthroscopically. The surgeon makes an incision less than 1 cm in the shoulder, assesses the location and extent of the damage, and then precisely covers the tendon with a collagen patch. Rather than pulling the tendon tightly and stitching it, the goal is to help the damaged tissue be naturally replaced with new tissue. When the damage is partial or involves thinning of the tendon, the patch may be used alone; for medium-sized or larger tears, it is applied as reinforcement in combination with conventional repair. After several months, the patch is completely absorbed in the body, and in many cases imaging studies such as MRI show newly proliferated tendon tissue.

Research in Korea and abroad has produced encouraging results. In an overseas randomized clinical trial comparing patients who underwent repair alone with those who received both repair and patch application, the re-tear rate decreased from the 25% range to around 8%, and pain reduction and functional recovery were also reported to be faster. In a domestic clinical study of patients with partial tears treated with collagen patches alone, without repair, pain decreased significantly and the thickness of the new tendon tissue increased by an average of 2 to 3 mm. In other words, collagen patches are highly meaningful as a form of "preventive treatment" before a complete tear occurs, helping restore the structure of an already thinned tendon and reducing the risk of re-tear.

This procedure also involves a small incision and minimal tissue damage, allowing for faster recovery, and is suitable even for patients with reduced healing capacity, such as the elderly or those with diabetes. Whereas conventional repair surgery increases tendon tension and carries a risk of re-tear, collagen patches act as a "reinforcing layer" in the necessary area, reducing mechanical stress. As a result, postoperative pain relief is faster and patients can return to daily activities sooner.

Of course, collagen patch treatment is not the answer for every patient. If the tear is already extensive or the tendon has retracted to the point where repair is difficult, other surgical options should be considered first. If you experience recurrent pain, a sense of resistance when lifting the arm, or aching pain at night, it is important not to delay and to visit an orthopedic clinic for early diagnosis. Considering collagen patch treatment at the appropriate time, before the damaged tendon progresses to a complete tear, can help protect the future health of your shoulder.

* The applicability of collagen patch treatment varies depending on the condition of each person's tendon and their activity level, and all treatment decisions must be made in consultation with a specialist.

Kim Mingyu, Chief of Orthopedics at SMG Yonsei Hospital

This content was produced with the assistance of AI translation services.