When discomfort arises in the hand and wrist, determining the exact cause can be challenging. Many people mistakenly use the terms carpal tunnel syndrome and tendonitis interchangeably. While both conditions affect the wrist and can be caused by repetitive motions, they involve different biological structures and present with distinct symptom patterns. Distinguishing between nerve compression and tendon inflammation is important for receiving the right diagnosis and effective treatment plan.
Understanding Carpal Tunnel Syndrome
Carpal Tunnel Syndrome (CTS) is caused by the compression of the median nerve as it passes through the carpal tunnel in the wrist. This narrow passageway is formed by the carpal bones and the transverse carpal ligament, accommodating the median nerve and nine flexor tendons. Swelling or structural changes within this confined space increase pressure on the nerve, leading to irritation or damage.
The classic symptoms of CTS are primarily neurological, involving the sensory distribution of the median nerve. Patients often experience numbness, tingling, or a burning sensation in the thumb, index finger, middle finger, and the thumb-side half of the ring finger. The little finger is typically unaffected. These symptoms frequently worsen at night, often waking the person, and can be temporarily relieved by shaking the hand.
Chronic nerve compression can cause weakness and clumsiness in the hand, making it difficult to grip objects or perform fine motor tasks. Repetitive wrist flexion or extension, the use of vibrating tools, and underlying health conditions can increase the risk. Risk factors include obesity, rheumatoid arthritis, diabetes, and thyroid disorders, as these can contribute to swelling or fluid retention.
Understanding Tendonitis
Tendonitis refers to the inflammation of a tendon in the wrist and hand. This condition is usually the result of acute injury or chronic overuse causing repetitive microtears in the tendon structure. Inflammation can also affect the tendon sheath, the protective layer surrounding the tendon, known as tenosynovitis.
The defining symptom is localized pain and tenderness directly over the affected tendon. This discomfort is often described as a dull ache or sharp sensation, exacerbated by movement that engages the tendon. The inflamed tendon may also feel stiff, particularly in the morning, and can sometimes be accompanied by visible swelling. In advanced or chronic cases, a creaking or popping sensation, known as crepitus, may be felt as the inflamed tendon struggles to glide smoothly within its sheath.
Key Differences in Symptoms and Causes
The fundamental distinction lies in the anatomical structure affected: CTS is a condition of the peripheral nervous system resulting from median nerve compression. Tendonitis, in contrast, is a musculoskeletal issue involving inflammation and irritation of the tendons themselves.
The nature of the symptoms provides the clearest differentiation. CTS manifests as neurological symptoms like numbness, tingling, and a pins-and-needles feeling in the median nerve distribution. Tendonitis causes localized pain, felt as a dull ache or sharp pain directly over the site of inflammation, related to the physical action of the affected tendon.
Symptom aggravation patterns also differ significantly. CTS symptoms are characteristically worse at night due to fluid retention and prolonged wrist flexion during sleep. Conversely, tendonitis pain is aggravated by specific, active movements that stress the inflamed tendon, such as gripping, twisting, or lifting objects.
Repetitive strain is a common factor in both, but leads to different outcomes. Repetitive movements can cause tendons to swell, increasing pressure inside the carpal tunnel and leading to CTS. However, the same stress can directly irritate and inflame the tendon sheath, causing tendonitis without necessarily compressing the median nerve.
Next Steps: When to Seek Professional Diagnosis
Self-assessing hand and wrist pain is difficult, making a professional medical evaluation necessary for an accurate diagnosis. A healthcare provider will perform a detailed physical examination, looking for specific signs of nerve compression or tendon inflammation. This examination may involve tests to reproduce symptoms, such as the Tinel’s sign or Phalen’s maneuver for CTS, or resisted movement tests for tendonitis.
For Carpal Tunnel Syndrome, definitive diagnosis often involves electrodiagnostic studies, such as Nerve Conduction Studies (NCS), to measure the speed and strength of electrical signals. Tendonitis diagnosis relies more on the physical examination and patient history. Initial management involves resting the affected hand, modifying activities, and wearing a simple wrist brace or splint for temporary support.