MSK

Carpal Tunnel Syndrome

SUMMARY:

Carpal tunnel syndrome (CTS) is a disease of the hand caused by compression of the median nerve as it travels through the carpal tunnel, a narrow and rigid passageway in the wrist enclosed by carpal bones and the transverse carpal ligament. Patients often present with intermittent hand pain, numbness and tingling. When diagnosis and treatment is delayed, prolonged compression of the median nerve can lead to irreversible damage and permanent neurologic deficits of the hand. Treatment includes splinting, local corticosteroid injections, and surgical decompression.

Clinical Presentation
Diagnosis
Treatment

Clinical Presentation

Patients typically present with gradually worsening symptoms in one or both hands
Symptoms can be intermittent at the start and become more constant as the disease progresses
- Mild disease: Intermittent symptoms | Pain | Paresthesia | No neuro deficits
- Moderate disease: Constant symptoms | Pain | Frequent nighttime awakenings | Hand clumsiness
- Severe disease: Thenar muscle atrophy | Motor deficits evident on exam | Constant symptoms
Pain is predominantly in the first four fingers (i.e., sparing the pinky finger) following the innervation path of the median nerve
- Numbness | Tingling | Burning | Shooting
- Pain may travel up the forearm to the shoulder
Later in the course of the disease patients may develop weakness and motor function losses
- Clumsiness of the hand | Dropping object
- Loss of fine motor control | Loss of proprioception
Symptoms often worsen with
- Sleep: Patients often sleep with wrists bent aggravating median nerve compression | Pain can disrupt sleep and cause nighttime awakenings
- Holding something for a prolonged period (e.g., Reading a book | Driving)
Symptoms can improve with: Moving or shaking the hand
Risk factors for CTS
- Family history of CTS | Repetitive hand use | Prolonged hand flexion/extension | Pregnancy | Diabetes | Arthritis | Hypothyroidism | Obesity | Female sex

Diagnosis

Obtain detailed history and physical exam
Include neck and upper arm exam to rule out:
- Cervical radiculopathy | Thoracic outlet | Pronator teres pathology | Ulnar and radial tunnel syndromes
Physical exam should include CTS provocative testing (see Learn More below)
- Tinel sign: Rapidly tap on the volar surface of the wrist proximal over the carpal tunnel | Testing positive if pain/paresthesia are elicited in the median nerve distribution | Sensitivity 50% | Specificity 77%
- Phalen test: Flex patient’s wrist 90 degrees with elbow in full extension for 60 seconds | Testing positive if pain/paresthesia are elicited in the median nerve distribution | Sensitivity 68% | Specificity 73%
- Closed fist sign: Patient makes a fist for 60 seconds | Testing positive if pain/paresthesia are elicited in the median nerve distribution
- Hand elevation test: Patient raises hand above their head for 60 seconds | Testing positive if pain/paresthesia are elicited in the median nerve distribution
- Manual carpal compression test: Apply direct pressure on the volar wrist surface over the carpal tunnel for 30 seconds | Testing positive if pain/paresthesia are elicited in the median nerve distribution | Sensitivity 64% | Specificity 83%
- Loss of two-point discrimination: Inability to discriminate between two points held ≤ 5 mm apart from one another on the palmar side of the first, second, or third digits
No single testing is completely predictive of CTS
- Exception: In severe cases, thenar muscle atrophy has a 99% specificity of CTS
Recommended to use a combination of physical exam findings and clinical presentation to make the diagnosis
Consider using the CTS-6 Evaluation Tool (under Learn More) to assist with diagnosis
- Score of ≥ 12 has an 80% probability for CTS
In typical mild cases of CTS, imaging and further invasive testing are not needed
Consider obtaining electrodiagnostic studies in cases of: Diagnostic uncertainty | Rule out additional pathology | Determine severity for surgical interventions
- Nerve conduction studies (NCS) | Electromyogram (EMG)

Treatment

Treatment of CTS depends on severity
- Many patients with non-severe symptoms will resolve spontaneously within 2 years
Non-surgical treatment should be offered for patients with mild to moderate CTS
Surgical treatment is recommended for patients with severe CTS or abnormal NCS/EMG studies

Non-surgical

Activity changes
- Use of keyboards with reduced strike force
- If computer mouse related, consider alternative options
- Limit activities that trigger CTS
- Physical therapy | Yoga | Occupational therapy | Therapeutic ultrasound
Splinting
- Neutral wrist splint is 1^st line for mild to moderate CTS
- Low risk | Low cost | Easy to access
- Night only splinting is as effective as continuous wear and is better tolerated
- Can consider wearing during the day for tasks that aggravate CTS symptoms
- Wear for at least 1 to 2 months | Expect symptom improvement after 2 weeks
Oral medications
- OTC anti-inflammatories (e.g., Acetaminophen | NSAIDs) have not been shown to be helpful in CTS
- Oral steroids may be effective for control of short-term symptoms but are associated with significant risks (e.g., Hyperglycemia | Adrenal insufficiency) and use should be limited
Local corticosteroid injection
- Provides significant improvement in symptoms and function
- Can take 3 months for full effect | Symptom improvement lasts roughly 6 months
- No significant difference among steroid formulations
- Combination of splinting and steroid injection had no additional benefits
Local perineural dextrose 5% injection
- Limited evidence that it may be effective for up to 6 months
- Second line therapy after: Splinting | Steroid injection

Surgical

Carpal tunnel release procedures are recommended for
- Severe CTS | Abnormal EMG/NCS testing | Failure of non-surgical treatments
Effective in most patients | Low risk | Requires referral to ortho or hand specialist
Endoscopic and open tunnel release techniques are equally effective
- Endoscopic approach may have less complications and a faster return to daily activities
Complications include: Bleeding | Infection | Wound healing issues | Nerve aggravation or injury
Clinical improvement and resolution of CTS symptoms may take several months post-operatively and recovery will depend on extent of pre-operative nerve damage

KEY POINTS:

Carpal tunnel syndrome (CTS) is a common disease of the hand caused by median nerve compression as it passes through the carpal tunnel
Diagnosis is based on a clinical picture of hand pain and paresthesia in a median nerve distribution in addition to suggestive physical exam findings
Further testing with EMG/NCS can be considered in atypical cases or to help determine severity of CTS
1^st line treatment for mild to moderate CTS is neutral wrist splinting and local corticosteroid injections
Patients with severe CTS or those who have failed non-surgical therapy should be referred for carpal tunnel decompression