Related Experiment Video
Updated: May 10, 2026
07:10
Modified Long Head of Biceps Tendon Rerouting and Fixation as Partial Capsular Reconstruction for Massive Irreparable Rotator Cuff Tears
Published on: March 6, 2026
Apoptosis occurs throughout the diseased rotator cuff
Hyo-Jin Lee1, Yang-Soo Kim, Ji-Hoon Ok
1Yang-Soo Kim, Department of Orthopedic Surgery, Seoul St Mary's Hospital, the Catholic University of Korea, 505 Banpo-dong, Seocho-gu, Seoul, Korea, 137-701. kysoos@catholic.ac.kr.
The American Journal of Sports Medicine
|June 22, 2013
Summary
Apoptosis occurs throughout torn rotator cuff tendons, not just at the margins. This suggests that debridement may not be necessary, and future treatments should focus on biological augmentation to prevent cell death.
Area of Science:
- Orthopedics
- Cell Biology
- Biochemistry
Background:
- Apoptosis (programmed cell death) is linked to rotator cuff tears.
- The specific location of apoptosis within the supraspinatus tendon remains unclear.
Purpose of the Study:
- To determine the precise location where apoptosis initiates within the supraspinatus tendon.
Main Methods:
- Collected supraspinatus tendon samples from patients with rotator cuff tears and controls.
- Assessed caspase 3/7, 8, 9, and cytochrome c activity to analyze apoptosis pathways.
- Utilized TUNEL staining and immunohistochemistry to identify apoptotic cells.
Main Results:
- Tendons from patients with rotator cuff tears exhibited significantly higher apoptotic activity than controls.
- No significant differences in apoptosis were observed between the torn margin, 1 cm medial, and posterior corner of the supraspinatus tendon.
- Increased expression of apoptosis markers (caspase 3/7, 8, 9, cytochrome c) was consistent across all sampled sites.
Conclusions:
- Apoptosis in rotator cuff tears involves both cell membrane receptor and mitochondrial pathways.
- Apoptosis occurs uniformly across the torn supraspinatus tendon, irrespective of location.
- Findings suggest debridement of torn margins may be unnecessary; focus should shift to biological augmentation for tendon healing.
Related Concept Videos
01:30Apoptosis
Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size reduction of the tissue.
01:31Muscles that Move the Arm
Nine muscles are involved in arm movements. Two of these, the pectoralis major and latissimus dorsi, originate from the axial skeleton and are called axial muscles. The other seven originate from the scapula and are called the scapular muscles.
The pectoralis major has two origins. Its clavicular head originates on the medial half of the clavicle. In contrast, the sternocostal head originates on the costal cartilages of ribs 1-6, the sternum, and the aponeurosis of the external oblique of the...
The pectoralis major has two origins. Its clavicular head originates on the medial half of the clavicle. In contrast, the sternocostal head originates on the costal cartilages of ribs 1-6, the sternum, and the aponeurosis of the external oblique of the...
01:18Autophagic Cell Death
Christian de Duve discovered “autophagy,” a process in which cellular components are engulfed by membrane-bound organelles called autophagosomes. The autophagosomes then fuse with lysosomes to digest the enclosed contents. Autophagy is generally activated in cells to prevent cell death. However, cell death is triggered when the damage is beyond repair.
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
01:22Cellular Injury V: Apoptosis and Autophagy
Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
01:17Phagocytosis of Apoptotic Cells
Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or immature dendritic cells. Non-professional phagocytes such as epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes.
Normal cells contain receptors that prevent them from being recognized by phagocytes.
Normal cells contain receptors that prevent them from being recognized by phagocytes.
01:30Overview of Cell Death
Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...