Tendon disorders are a common cause of musculoskeletal pain and functional impairment, particularly among individuals participating in repetitive physical activity, occupational tasks and sport. Although the terms tendinopathy, tendinitis and tendinosis are frequently used interchangeably, they describe different aspects of tendon pathology.
Understanding these distinctions is important for clinical assessment, exercise prescription and the development of appropriate rehabilitation strategies.
Tendinopathy
Tendinopathy is an umbrella term used to describe a clinical condition characterised by tendon pain, impaired function and reduced tolerance to mechanical loading.
It commonly develops in response to repetitive or excessive tendon loading, particularly when the applied mechanical demands exceed the tendon's capacity to adapt and recover.
Common examples include Achilles tendinopathy, patellar tendinopathy, and rotator cuff-related tendon disorders.
Clinical presentations typically include:
Localised pain during loading.
Tenderness over the affected tendon.
Reduced capacity to perform activities requiring tendon loading.
Reduced muscular strength or functional performance.
Importantly, the term tendinopathy does not imply a specific underlying histopathological process. Tendon pain and dysfunction may occur without a direct relationship to the degree of structural change identified through imaging.
Tendinitis
Tendinitis refers to inflammation of a tendon.
Historically, the term was frequently used to describe tendon pain associated with repetitive loading. However, research has demonstrated that many persistent tendon disorders involve complex cellular and extracellular matrix changes rather than a predominantly inflammatory pathology.
Inflammatory processes can contribute to tendon disorders, particularly in acute presentations, but inflammation is not necessarily the primary mechanism responsible for persistent tendon pain.
Consequently, tendinopathy is generally the preferred clinical term when the underlying pathology has not been established.
Tendinosis
Tendinosis describes degenerative or disorganised structural changes within tendon tissue.
These changes may include altered collagen organisation, changes in tenocyte activity and disruption of the normal extracellular matrix.
Tendinosis has traditionally been associated with chronic tendon overloading and impaired tissue adaptation.
Clinical Management and Exercise Rehabilitation
Exercise-based rehabilitation is a cornerstone of conservative tendinopathy management.
Progressive mechanical loading aims to improve the tendon-muscle unit's capacity to tolerate physical demands while restoring strength and functional performance.
Common approaches include:
Isometric exercise: May provide an accessible starting point for individuals experiencing pain during dynamic loading, although its immediate analgesic effects are variable.
Eccentric exercise: Eccentric exercise may increase the proliferation of fibroblasts which can lead to increased collagen synthesis in response to mechanical loading and improve the integrity of musculo-tendinous structures by inducing hypertrophy and increased tensile strength.
Energy-storage exercises: Plyometric and other dynamic loading activities can be introduced when appropriate to prepare the tendon for running, jumping and sport-specific demands.
Exercise selection and progression should be guided by symptom irritability, functional capacity, loading history and individual rehabilitation goals.
Key Takeaway
Tendinopathy is the preferred umbrella term for tendon pain and impaired loading capacity. Tendinitis specifically refers to inflammation, while tendinosis describes structural tendon degeneration.
Accurate terminology, appropriate clinical assessment and progressive exercise loading are important components of effective tendon rehabilitation.
C. Johnston