Giải ép ống cổ tay

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview¶

• Symptoms of pain, numbness, and tingling in the hands are common in the general population [1].

Anatomy & Pathophysiology¶

Epidemiology & Symptoms¶

• Carpal tunnel syndrome with compression of the median nerve at the wrist is the most commonly diagnosed site of nerve compression in the upper extremity [10].
• Symptoms include paresthesia or numbness (or both) in the median nerve distribution, specifically the thumb, index finger, middle finger, and radial side of the ring finger [10].
• Nocturnal paresthesias in the radial three digits of the hand is nearly pathognomonic for carpal tunnel syndrome [10].
• Paresthesias occur characteristically in "fixed wrist activities" such as reading a book or a newspaper, driving, or use of a computer keyboard or mouse [10].
• Patients rarely describe aching in the thenar eminence [10].
• With advanced nerve compression, weakness and atrophy of the abductor pollicis brevis and opponens pollicis muscles occur [10].
• Because of the slow onset of thenar weakness, patients typically adapt to this loss without functional impairments [10].

Pathogenesis¶

• Bony abnormalities of the carpal bones can decrease the size of the carpal tunnel [5].
• Acromegaly can decrease the size of the carpal tunnel [5].
• Flexion or extension of the wrist can decrease the size of the carpal tunnel [5].
• Forearm and wrist fractures, including Colles fracture and scaphoid fracture, can increase the contents of the carpal canal [5].
• Dislocations and subluxations, including scaphoid rotary subluxation and lunate volar dislocation, can increase the contents of the carpal canal [5].
• Posttraumatic arthritis with osteophytes can increase the contents of the carpal canal [5].
• Musculotendinous variants can increase the contents of the carpal canal [5].
• Aberrant muscles, including lumbrical, palmaris longus, and palmaris profundus, can increase the contents of the carpal canal [5].
• Local tumors, including neuroma, lipoma, multiple myeloma, and ganglion cysts, can increase the contents of the carpal canal [5].
• A persistent medial artery, whether thrombosed or patent, can increase the contents of the carpal canal [5].
• Hypertrophic synovium can increase the contents of the carpal canal [5].
• Hematoma resulting from hemophilia, anticoagulation therapy, or trauma can increase the contents of the carpal canal [5].
• Diabetes mellitus is a neuropathic condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Alcoholism is a neuropathic condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Double-crush syndrome is a neuropathic condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Exposure to industrial solvents is a neuropathic condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Rheumatoid arthritis is an inflammatory condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Gout is an inflammatory condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Nonspecific tenosynovitis is an inflammatory condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Infection is an inflammatory condition involved in the pathogenesis of carpal tunnel syndrome [5].
• Pregnancy involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Menopause involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Eclampsia involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Thyroid disorders, especially hypothyroidism, involve alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Renal failure involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Long-term hemodialysis involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Raynaud disease involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Obesity involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Lupus erythematosus involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Scleroderma involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Amyloidosis involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Paget disease involves alterations of fluid balance in the pathogenesis of carpal tunnel syndrome [5].
• Vibration is an external force involved in the pathogenesis of carpal tunnel syndrome [5].
• Direct pressure is an external force involved in the pathogenesis of carpal tunnel syndrome [5].

Anatomical Structures & Surgical Landmarks¶

• The palmar cutaneous sensory branch of the median nerve lies in the interval between the palmaris longus and the flexor carpi radialis tendons [4].
• The palmar cutaneous branch of the median nerve is located deep to the thenar crease and radial to the palmaris longus [11].
• The superficial palmar arterial arch is 5 to 8 mm distal to the distal margin of the transverse carpal ligament [4].
• The flexor retinaculum includes the distal deep fascia of the forearm proximally, the transverse carpal ligament, and the aponeurosis between the thenar and hypothenar muscles [4].
• Fibers of the transverse carpal ligament can extend distally farther than expected [4].
• The recurrent branch of the median nerve may perforate the transverse carpal ligament and leave the median nerve on the volar side [4].
• Potential anatomical anomalies include connections between the flexor pollicis longus and the index flexor digitorum profundus tendons [4].
• Potential anatomical anomalies include anomalous flexor digitorum superficialis [4].
• Potential anatomical anomalies include palmaris longus, hypothenar, and lumbrical muscle bellies [4].
• Potential anatomical anomalies include median and ulnar nerve branches and interconnections [4].
• The thenar crease takes a variable course [4].
• A crossing cutaneous branch from the ulnar nerve is identified in a distal portion of the incision about 15% of the time [11].

Diagnostic & Prognostic Factors¶

• Carpal tunnel syndrome is a clinical diagnosis based on a combination of symptoms and characteristic physical findings [10].
• Electrodiagnostic studies are useful to stage the degree of nerve compression and assist in anticipating the time needed for recovery of nerve function [10].
• Patients with long-standing symptoms, severe atrophy of the thenar musculature, and dense sensory loss should be cautioned that release may not lead to complete recovery of sensation or thenar strength [10].
• Ultrasound sensitivity for carpal tunnel syndrome has been reported to be over 97% when the median nerve diameter is greater than 10 mm² at the level of the pisiform [5].
• In patients with negative electrodiagnostic studies but a clinical diagnosis of carpal tunnel syndrome, high-resolution ultrasonography has a sensitivity of 73% if the cutoff of 9.4 mm² at the inlet of the carpal tunnel is used [5].
• The diagnosis of carpal tunnel syndrome should be based on clinical acumen and physical examination in the vast majority of patients [5].
• Ancillary tests should be reserved for patients without clear presentations [5].
• MRI is not routinely used for diagnosis of carpal tunnel syndrome [5].
• A major advantage of MRI is its high soft-tissue contrast, which gives detailed images of bones and soft tissues [5].
• Reported false-negative rates of electrodiagnostic testing are 10% [5].
• Postoperative electrodiagnostic testing may be helpful in assessing recurrent symptoms [5].

Clinical Presentation¶

Epidemiology and Risk Factors¶

• Carpal tunnel syndrome is the most common compression neuropathy of the upper extremity [9].
• The mean age at diagnosis for carpal tunnel syndrome is 50 years [9].
• Carpal tunnel syndrome is more common in women than men by nearly four times [9].
• By the age of 65 years, the prevalence of carpal tunnel syndrome is approximately 5.1% for women and 1.3% for men [9].
• Risk factors for carpal tunnel syndrome include obesity, pregnancy, hypothyroidism, diabetes mellitus, and menopause [9].
• The American Academy of Orthopaedic Surgeons guidelines list body mass index (BMI) and high hand repetition rate as factors with strong evidence of increased risk for development of carpal tunnel syndrome [9].

Clinical Symptoms and Signs¶

• Classically, carpal tunnel syndrome presents with nocturnal paresthesias in a median nerve distribution that gradually worsen as nerve injury progresses [9].
• Late in the disease course, carpal tunnel syndrome leads to sensory loss and thenar muscle atrophy [9].
• Many patients report pain in the hand and may report symptoms that are not directly referable to the median nerve [9].
• A positive Tinel sign at the wrist can aid in the diagnosis of carpal tunnel syndrome [9].
• Development of symptoms after a provocative Phalen maneuver can aid in the diagnosis of carpal tunnel syndrome [9].
• The reported specificity of the Tinel sign at the wrist varies from 55% to 100% [9].
• The reported specificity of the Phalen test varies from 54% to 98% [9].
• Tinel sign and Phalen maneuver are most reliable as adjuncts to other diagnostic tests [9].

Diagnostic Testing¶

• Nerve conduction studies are a useful diagnostic tool for carpal tunnel syndrome, assessing focal demyelination by delayed conduction velocities of the median nerve at the wrist [9].
• Needle electromyography is considered an optional adjunct to nerve conduction studies and is mostly used to differentiate carpal tunnel syndrome from other possible causes [9].
• Documenting muscle atrophy and fibrillations on needle EMG can assist with identifying severity of the disease and help with prognostication [9].
• Thenar atrophy and abductor pollicis brevis weakness can often be detected on physical examination [9].
• Ultrasonography allows rapid diagnosis of carpal tunnel syndrome by identification of enlarged, hypoechoic median nerve fascicles proximal to the carpal tunnel [9].
• Controversy remains as to whether ultrasonography evaluation could replace electrophysiology in the diagnosis of carpal tunnel syndrome [9].
• MRI and/or ultrasonography imaging should be considered in patients who have new, persistent, or recurrent symptoms after surgery to delineate the etiology of the symptoms [9].
• Ancillary tests for carpal tunnel syndrome should be reserved for patients without clear presentations [5].
• Reports of MRI in carpal tunnel syndrome are promising, especially with newer techniques such as diffusion tensor imaging [5].

Pathogenesis Factors¶

• Bony abnormalities of the carpal bones are a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Acromegaly is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Flexion or extension of the wrist is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Forearm and wrist fractures, such as Colles fracture and scaphoid fracture, are factors involved in the pathogenesis of carpal tunnel syndrome [5].
• Dislocations and subluxations, such as scaphoid rotary subluxation and lunate volar dislocation, are factors involved in the pathogenesis of carpal tunnel syndrome [5].
• Posttraumatic arthritis with osteophytes is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Musculotendinous variants are a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Aberrant muscles, including lumbrical, palmaris longus, and palmaris profundus, are factors involved in the pathogenesis of carpal tunnel syndrome [5].
• Local tumors, including neuroma, lipoma, multiple myeloma, and ganglion cysts, are factors involved in the pathogenesis of carpal tunnel syndrome [5].
• A persistent medial artery, whether thrombosed or patent, is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Hypertrophic synovium is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Hematoma from hemophilia, anticoagulation therapy, or trauma is a factor involved in the pathogenesis of carpal tunnel syndrome [5].
• Pregnancy is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Menopause is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Eclampsia is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Thyroid disorders, especially hypothyroidism, are alterations of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Renal failure is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Long-term hemodialysis is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Raynaud disease is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Obesity is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Lupus erythematosus is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Scleroderma is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Amyloidosis is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].
• Paget disease is an alteration of fluid balance involved in the pathogenesis of carpal tunnel syndrome [5].

Investigations¶

Clinical Presentation and Prevalence¶

• The American Academy of Orthopaedic Surgeons (AAOS) guidelines list body mass index (BMI) and high hand repetition rate as factors with strong evidence of increased risk for development of carpal tunnel syndrome [9].

Physical Examination¶

Electrodiagnostic Testing¶

• Nerve conduction studies remain a useful diagnostic tool in carpal tunnel syndrome [9].
• Focal demyelination in carpal tunnel syndrome can be assessed by delayed conduction velocities of the median nerve at the wrist [9].
• Needle electromyography is currently considered an optional adjunct to nerve conduction studies [9].
• Needle electromyography is mostly used to differentiate carpal tunnel syndrome from other possible causes [9].
• Pre-operative electrodiagnostic testing predicts time to resolution of symptoms after carpal tunnel release [3].
• Reported false-negative rates of 10% limit the usefulness of electrodiagnostic testing to determine treatment [5].
• Electrodiagnostic testing does not increase the diagnostic value of the four commonly used clinical tests (abnormal hand diagram, abnormal Semmes-Weinstein, positive Durkan compression, and night pain) [5].
• Electrodiagnostic testing does not predict functional recovery or reemployment after carpal tunnel release [5].

Imaging¶

• MRI is not routinely used for the diagnosis of carpal tunnel syndrome [5].
• Advances in ultrasonography technology have allowed rapid diagnosis of carpal tunnel syndrome by identification of enlarged, hypoechoic median nerve fascicles proximal to the carpal tunnel [9].
• Imaging can help identify causes of postoperative symptoms such as incomplete ligament division, iatrogenic injury, or other causes [9].

Diagnostic Principles¶

• The diagnosis of carpal tunnel syndrome is made by clinical history, physical examination, and supportive diagnostic testing with exclusion of other possible disorders [9].

Treatment¶

Operative Technique¶

• Palmar incisions for carpal tunnel release should be placed well ulnar to the thenar crease to avoid injury to the median nerve palmar cutaneous branch [4].
• A curved incision ulnar and parallel to the thenar crease is not advisable because the palmar cutaneous branch of the median nerve may be at higher risk of injury proximally [4].
• The incision should be extended proximally to the wrist flexion crease and angled toward the ulnar side of the wrist to avoid crossing flexor creases at a right angle [4].
• The palmar cutaneous sensory branch lies in the interval between the palmaris longus and the flexor carpi radialis tendons [4].
• If the palmar sensory branch is severed, it frequently causes a painful neuroma that may later require excision from the scar [4].
• When the palmar sensory branch is severed, repair is not attempted; instead, the nerve is sectioned more proximally to be covered by the middle finger sublimis muscle [4].
• The transverse carpal ligament (TCL) must be carefully divided while avoiding damage to the median nerve and its recurrent branch, which may perforate the ligament and leave the median nerve on the volar side [4].
• Fibers of the TCL can extend distally farther than expected [4].
• The flexor retinaculum includes the distal deep fascia of the forearm proximally, the TCL, and the aponeurosis between the thenar and hypothenar muscles [4].
• A successful carpal tunnel release usually requires division of all components of the flexor retinaculum [4].
• Potential anatomical anomalies to be aware of include connections between the flexor pollicis longus and index flexor digitorum profundus tendons, anomalous flexor digitorum superficialis, palmaris longus/hypothenar/lumbrical muscle bellies, and median/ulnar nerve branches and interconnections [4].
• The superficial palmar arterial arch is located 5 to 8 mm distal to the distal margin of the TCL and must be avoided [4].
• Tenosynovectomy is occasionally indicated, especially in patients with rheumatoid arthritis [4].
• Closure involves only the skin, with wound drainage as needed [4].

Postoperative Care¶

• A light compression dressing and a volar splint may be applied postoperatively [4].
• The hand is actively used as soon as possible after surgery, but the dependent position is avoided [4].
• The dressing can usually be removed by the patient at home 2 or 3 days after surgery [4].
• Gentle washing and showering of the hand are permitted after dressing removal [4].
• Gradual resumption of normal hand use is encouraged [4].
• Sutures are removed after 10 to 14 days [4].
• A splint may be continued for comfort as needed for 14 to 21 days [4].

Complications¶

• Transection of the motor branch of the ulnar nerve is a complication of two-portal endoscopic carpal tunnel release [2].
• Scar discomfort can occur after carpal tunnel surgery [2].
• Recurrent carpal tunnel syndrome is a recognized clinical entity following carpal tunnel release [2].
• Poor outcome is associated with neural surgery (epineurotomy or neurolysis) for carpal tunnel syndrome compared with carpal tunnel release alone [2].
• Symptoms may return after carpal tunnel surgery [2].
• Complications related to carpal tunnel release are a documented clinical concern [2].
• Carpal tunnel release in patients with diabetes results in poor outcomes in long-term study [3].

Key Evidence¶

• [L4] Symptoms of pain, numbness, and tingling in the hands are common in the general population. [1] (10.1001/jama.282.2.153)

References¶

[1] Prevalence of Carpal Tunnel Syndrome in a General Population. JAMA. 1999. DOI: 10.1001/jama.282.2.153

[2] Campbell S Operative Orthopaedics 4 Volume Set. COMPRESSIVE NEUROPATHIES OF THE HAND, FOREARM, AND ELBOW > CARPAL TUNNEL SYNDROME.

[3] Campbell S Operative Orthopaedics 4 Volume Set. COMPRESSIVE NEUROPATHIES OF THE HAND, FOREARM, AND ELBOW > REFERENCES > CARPAL TUNNEL SYNDROME.

[4] Campbell S Operative Orthopaedics 4 Volume Set. COMPRESSIVE NEUROPATHIES OF THE HAND, FOREARM, AND ELBOW > EXTENDED OPEN CARPAL TUNNEL RELEASE.

[5] Campbell S Operative Orthopaedics 4 Volume Set. COMPRESSIVE NEUROPATHIES OF THE HAND, FOREARM, AND ELBOW > CARPAL TUNNEL SYNDROME > BOX 77.1.

[9] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Neuropathies, Vascular Conditions: Buerger’s, Raynaud’s; Degenerative Conditions > Upper Extremity Neuropathies > Carpal Tunnel Syndrome.

[10] Green S Operative Hand Surgery. Median Nerve Compression at the Elbow and Forearm > COMPRESSION OF THE MEDIAN NERVE > Median Nerve Compression at the Wrist: Carpal Tunnel Syndrome.

[11] Green S Operative Hand Surgery. Median Nerve Compression at the Elbow and Forearm > AUTHORS’ PREFERRED METHOD OF TREATMENT: OPEN CARPAL TUNNEL RELEASE.