title: Is resection of the tendon edge necessary to enhance the healing process? An evaluation of the homeostasis of apoptotic and inflammatory processes in the distal 1 cm of a torn supraspinatus tendon: part I.
abstract: BACKGROUND
  We hypothesize that the expression of proapoptotic and antiapoptotic molecules and cytokines is dependent on the distance from the torn supraspinatus tendon edge and this expression may influence its potential for healing. The aim of this work is to evaluate the expression of proapoptotic Bax molecule and caspases 3, 8, and 9; antiapoptotic Bcl-2 molecule; and proinflammatory tumor necrosis factor (TNF) α and anti-inflammatory interleukin 10 (IL-10) in 3 sections taken from a 1-cm section of the edge of a torn supraspinatus tendon: 3 mm distal and 3 mm proximal, as well as the remaining 4-mm middle section between them.
  
  
  METHODS
  Nine patients, with a mean age of 58 years, were included in the study. All fulfilled strict inclusion criteria regarding the morphology of the tear and reconstruction technique. Samples were taken from the ruptured supraspinatus tendon at the time of arthroscopic repair. Quantitative real-time polymerase chain reaction assay was used for analysis.
  
  
  RESULTS
  The expression of caspases 9, 8 and 3; Bax; and TNF-α significantly decreased from the distal to the proximal parts of the tendon edge (P < .05). However, a significant increase in Bcl-2 and IL-10 expression was also found in the same direction (P < .05).
  
  
  CONCLUSIONS
  Tenocytes can reduce the expression of proapoptotic caspases 3, 8, and 9 and Bax, as well as proinflammatory TNF-α, by increasing the expression of Bcl-2 and IL-10 within 1 cm of the supraspinatus edge in a distal to proximal direction. Resection 4 to 7 mm from the edge of the torn supraspinatus tendon may enhance the healing process by reaching a reasonable compromise between molecular homeostasis of apoptotic and inflammatory processes and mechanical aspects of rotator cuff reconstruction.
authors.affiliation: Department of Arthroscopy, Minimally Invasive Surgery and Sports Traumatology, Medical University of Łódź, Łódź, Poland; FMC Private Medical Centre, Łódź, Poland. Electronic address: fabis@onet.eu.
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Fabiś
authors.affiliation: Department of Medical Biochemistry, Medical University of Łódź, Łódź, Poland.
authors.forename: Janusz
authors.initials: J
authors.lastname: Szemraj
authors.affiliation: Department of Nucleic Acids Biochemistry, Medical University of Łódź, Łódź, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Strek
authors.affiliation: FMC Private Medical Centre, Łódź, Poland; Polish Mother's Memorial Research Institute, Łódź, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Fabiś
authors.affiliation: Department of Hand Surgery, Medical University of Łódź, Łódź, Poland.
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Dutkiewicz
authors.affiliation: Department of Arthroscopy, Minimally Invasive Surgery and Sports Traumatology, Medical University of Łódź, Łódź, Poland.
authors.forename: Tomasz Jacek
authors.initials: TJ
authors.lastname: Zwierzchowski
mesh_terms: D000368:Aged; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis; D001182:Arthroscopy; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D006706:Homeostasis; D006801:Humans; D007249:Inflammation / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017006:Rotator Cuff / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D000070636:Rotator Cuff Injuries; D013708:Tendon Injuries / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D013710:Tendons / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D014945:Wound Healing / Q000502:physiology*
chemical_list: D051017:Apoptosis Regulatory Proteins; D016207:Cytokines
keywords: Apoptosis; cytokines; homeostasis; supraspinatus tendon resection