introduction to tendinopathy

• what colour are healthy tendons?


  white
• what is enthesis?


  the site of attachment from tendon to bone
• what is the tendon designed to do?


  minimise stress and allow for load transfer
• what is the tendon body made up of?

  • Extracellular Matrix (ECM) of tendon itself is composed predominantly of collagen (60-85%) and roughly 95% of the collagen is type I
  • Proteins (proteoglycans and glycoproteins), elastin fibres (1–10% tendon dry weight) 
  • Cells – specialized fibroblasts, mast cells, macrophages
• what are musculotendinous junctions?


  point at which the the tendon forms attachment to the muscle
• What are the fibroblastic cellular components of tendons called?


  Tenocytes
• What is the primary function of tenocytes in tendons?


  They synthesize extracellular matrix and respond to mechanical loads
• How are collagen fibrils organized in tendons?


  They are grouped together like a 'rope'
• What is the structure of collagen fibers in tendons?


  They are grouped to form Primary, Secondary & Tertiary fibers or Fascicles
• What is the sheath that binds collagen fibrils in tendons called?


  Endotenon
• stress and strain curve in tendon

  • Parallel arrangement of the collagen resists tensile loading (stress) without too much elongation (strain)
  • Some tendons have an energy storing capacity
  • BUT high repetitive stresses and strains may leave them more prone to injuries
• What is the composition of a tendon?


  A tendon is composed of a group of fascicles bound by endotenon and epitenon
• What is the exterior sheath of connective tissue surrounding a tendon called?

  Epitenon
• What is the function of the paratenon in relation to tendons?


  It is fatty tissue located between fascia and tendon tissues
• What are the key structural components of a tendon?

  • Tenocytes: fibroblastic cells that synthesize extracellular matrix
  • Collagen fibrils: grouped like a 'rope'
  • Collagen fibers: grouped into Primary, Secondary & Tertiary fibers (Fascicles)
  • Endotenon: sheath binding collagen fibrils
  • Epitenon: exterior sheath of connective tissue
  • Paratenon: fatty tissue between fascia and tendon
• What is the general term for tendon degeneration?

  Tendinopathy
• what happens in tendinopathy?

  • Histological studies of surgical specimens from patients with established tendinopathy consistently show either absent or minimal inflammation.
  • They generally also show hypercellularity, a loss of the tightly bundled collagen fiber appearance, an increase in proteoglycan content, and commonly neovascularization 
  • Unloading a tendon induces cell and matrix changes similar to those seen in an overloaded state and decreases the mechanical integrity of the tendon.
• What are the characteristics of tendinopathy?


  It is characterized by tendon pain, swelling, and impaired performance
• How is tendinopathy classified?


  It is effectively a syndrome of signs and symptoms that characterize a particular condition
• What does the term 'tendinosis' refer to?


  Degeneration of the tendon’s collagen in response to chronic overuse
• What is 'tenosynovitis'?


  Inflammation of the sheath that surrounds a tendon
• What does 'para or peri tendonitis' involve?


  Involvement of the adjacent paratenon, which can occur alone or with tendinosis
• What are the associated terms related to tendinopathy?

  • Tendinosis: degeneration of tendon collagen due to chronic overuse
  • Tenosynovitis: inflammation of the tendon sheath
  • Para or peri tendonitis: involvement of the adjacent paratenon, alone or with tendinosis
• things to think about in physiotherapy assessment

  • Muscle atrophy
  • Asymmetry
  • Swelling
  • Erythema
  • Range of motion
  • Loading tests
• what does it mean for management?

  • No quick fix 
  • Healing and return to sport takes time
  • Tendon has limited vascularity and slow metabolic rate  
  • Tenocytes have a slow turnaround rate 50-100 days  
  • Each patient will present with their own collection of clinical features so arguable if there is a ‘recipe’ 
  • It is about favorably affecting tendon homeostasis to prevent poor quality repair and tendon deconditioning 
  • Appropriate loading dealing with extrinsic and intrinsic factors
  • If given inadequate time to repair tenocytes can undergo apoptosis