Carpal Tunnel Release

What is carpal tunnel release?

Carpal tunnel release is an operation that treats carpal tunnel syndrome by reducing pressure on the median nerve where it passes through the wrist. The surgeon divides the transverse carpal ligament—the strong band of tissue forming the roof of the carpal tunnel—so the tunnel has more space and the compressed nerve can recover.

Carpal tunnel syndrome develops when pressure increases around the median nerve inside the carpal tunnel. This tunnel is a narrow anatomical passage at the wrist. Its floor and sides are formed by the carpal bones, while the transverse carpal ligament forms its roof. The median nerve and the flexor tendons that bend the fingers travel through this confined space. Because the tunnel cannot expand easily, swelling or reduced available space can compress the nerve.

The median nerve provides sensation to the thumb, index finger, middle finger and the thumb-side portion of the ring finger. It also supplies muscles involved in important thumb movements. Compression can therefore cause tingling, numbness, burning discomfort, night-time symptoms, weakness, clumsiness and a tendency to drop objects. Advanced median-nerve compression can eventually produce persistent loss of sensation and wasting of the muscles at the base of the thumb.

The objective of carpal tunnel release surgery is decompression. It does not remove the median nerve, replace it or normally reconstruct it. Instead, the surgeon releases the tight ligament above it.

After division, the transverse carpal ligament heals with more space underneath it. This increased space decreases pressure on the median nerve and improves the conditions in which the nerve can function and recover.

Why is the transverse carpal ligament cut?

Patients sometimes worry that cutting a ligament must make the wrist unstable. Carpal tunnel release is different from cutting one of the major ligaments responsible for stabilising the wrist joint.

The transverse carpal ligament is deliberately divided because it forms the rigid roof of the carpal tunnel. Releasing it increases the tunnel's volume and reduces compression on the nerve. The ligament subsequently heals in a lengthened configuration rather than recreating the same degree of pressure.

The fundamental goal is therefore the same regardless of whether surgery is performed through an open incision, a smaller mini-open incision or an endoscopic approach: complete division of the transverse carpal ligament without damaging the median nerve or nearby structures.

What symptoms can carpal tunnel release improve?

Surgery is intended to treat symptoms arising from median-nerve compression at the wrist. Common symptoms include:

• numbness or tingling affecting the thumb, index and middle fingers and part of the ring finger;

• symptoms that are especially troublesome at night;

• burning or electric sensations in the hand;

• pain that may extend into the forearm;

• weakness or reduced grip;

• difficulty manipulating small objects;

• clumsiness;

• dropping objects;

• reduced thumb strength;

• persistent sensory loss in more advanced disease.

Night-time tingling and pain may improve rapidly after adequate decompression. AAOS patient guidance notes that night symptoms improve markedly in many patients during the first week. Sensory recovery after severe or long-standing compression is less predictable and can continue for 6–12 months.

This distinction matters. Carpal tunnel release removes ongoing compression; it cannot guarantee reversal of nerve damage that has already become permanent.

A person who has mild intermittent tingling for a relatively short period may therefore recover differently from someone who has had constant numbness, severe electrodiagnostic abnormalities and visible thenar-muscle wasting for several years.

Does carpal tunnel release cure carpal tunnel syndrome?

For many appropriately selected patients, surgery produces substantial and durable symptom improvement. NHS England decision-support data report that approximately 75–92 out of 100 people in the evidence used for that tool felt better after surgery at one year. However, not every patient becomes completely symptom-free.

Poorer or slower neurological recovery is more likely when nerve compression has been severe or present for a long time. Patients with constant numbness or thenar-muscle wasting should understand that the purpose of surgery may be partly to prevent further deterioration, even when full sensation or strength cannot be promised.

Persistent symptoms can also occur when another condition is contributing—for example cervical radiculopathy, generalized peripheral neuropathy, arthritis, tendon disease or compression of the median nerve at another anatomical level.

Good diagnosis before surgery is therefore as important as the technical operation.

Open versus endoscopic carpal tunnel release

Two widely established approaches are open carpal tunnel release and endoscopic carpal tunnel release.

In open surgery, the surgeon makes an incision in the palm, visualises the transverse carpal ligament directly and divides it.

In endoscopic carpal tunnel release, one or two small portals are made and a small camera allows the surgeon to see the ligament from inside the tunnel while a specialised instrument divides it.

The 2024 AAOS clinical practice guideline found strong evidence that mini-open and endoscopic carpal tunnel release provide no meaningful difference in long-term patient-reported outcomes. The guideline notes that endoscopic surgery may permit earlier return to work in some settings, while costs, surgeon training and technique-specific risks also need consideration.

A 2024 umbrella review similarly reported broadly comparable outcomes, while finding a shorter return-to-work interval after endoscopic release in pooled evidence.

More recent comparative evidence also supports the principle that long-term pain relief, function and sensory outcomes are broadly comparable among open, mini-open and endoscopic approaches.

This means the word “endoscopic” should not automatically be interpreted as “better.” The appropriate approach depends on anatomy, previous surgery, surgeon expertise, equipment availability, cost, patient preference and the specific clinical problem.

Is carpal tunnel release major surgery?

It is generally considered a relatively small operation in terms of incision size, anaesthetic requirement and hospital stay, but it is still genuine nerve decompression surgery.

Important structures—including the median nerve and its branches—lie close to the surgical field. Complications such as nerve injury, infection, incomplete release, painful scarring and persistent symptoms are uncommon but possible.

For this reason, carpal tunnel surgery should be performed by a clinician appropriately trained in hand and wrist surgery and in the specific technique being offered.

A good candidate for carpal tunnel release has symptoms and clinical findings that are reasonably attributable to compression of the median nerve at the wrist and for whom the expected benefits of decompression outweigh the surgical risks.

Typical candidates report numbness, tingling or burning in a median-nerve distribution, often worse at night. They may wake from sleep and shake the hand to relieve symptoms. Some experience weakness, difficulty with fine movements or frequent dropping of objects.

Surgery is not automatically necessary as soon as carpal tunnel syndrome is diagnosed. Mild cases often begin with non-surgical management such as night splinting, activity modification or, in selected patients, corticosteroid injection. The British Society for Surgery of the Hand states that surgery is generally offered when symptoms are severe or have not improved with conservative care.

NHS England decision support describes carpal tunnel release as an option when symptoms persist after approximately 6–12 weeks of other management, when symptoms are severe or long-standing, or when testing demonstrates nerve damage or muscle wasting. That timescale is not a mandatory rule for every patient: severe neurological deficit can justify earlier surgical consideration.

Severe disease may need earlier surgery

Waiting indefinitely for splints or injections to work is not appropriate when the median nerve is already significantly compromised.

Warning signs of more advanced disease can include:

• constant rather than intermittent numbness;

• loss of fingertip sensation;

• objective thumb weakness;

• dropping objects because of weakness or impaired sensation;

• muscle wasting at the base of the thumb;

• severe nerve-conduction abnormalities;

• progressive symptoms despite appropriate treatment.

AAOS guidance notes that long-standing compression associated with constant numbness or muscle wasting may lead surgeons to recommend decompression to prevent irreversible deterioration.

Is a nerve-conduction study required before surgery?

Not in every patient.

The updated 2024 AAOS guideline supports use of the CTS-6 clinical diagnostic tool instead of routinely requiring ultrasound or nerve-conduction/EMG testing in every straightforward case.

BSSH likewise states that nerve-conduction studies are not always necessary when the diagnosis is clinically clear and symptoms are typical.

Testing can nevertheless be useful when:

• the diagnosis is uncertain;

• symptoms are atypical;

• severe nerve damage is suspected;

• another neuropathy may coexist;

• cervical radiculopathy is possible;

• symptoms have returned after previous surgery;

• there is diabetes or generalized neuropathy;

• objective baseline nerve function would help guide prognosis.

A high-quality Orthopedic Abroad consultation should therefore avoid both extremes: neither ordering every possible investigation automatically nor skipping appropriate testing in a complicated case.

Diabetes and carpal tunnel release

Diabetes does not automatically exclude a patient from surgery. A systematic review found that patients with diabetes generally experienced improvement after carpal tunnel surgery, although underlying diabetic neuropathy and sensory nerve dysfunction can affect recovery.

Patients with diabetes require individualized assessment of glucose control, wound-healing risk, neuropathy and other medical conditions.

Older patients

Advanced age alone is not an automatic contraindication. Suitability depends more on the patient's symptoms, nerve condition, medical status and expected benefit than on chronological age.

Pregnancy

Carpal tunnel symptoms during pregnancy can improve after delivery as fluid retention and hormonal changes resolve. Therefore surgery is not automatically the first choice for pregnancy-associated CTS. Persistent severe neurological deficit needs specialist evaluation.

When someone may not be an ideal immediate candidate

Surgery may need to be postponed or reconsidered when:

• the diagnosis is uncertain;

• symptoms appear to originate mainly from the neck or another nerve;

• there is active infection near the surgical site;

• an uncontrolled medical condition significantly increases procedural risk;

• expectations are unrealistic;

• symptoms are mild and have not yet justified surgery;

• numbness is caused mainly by a generalized neuropathy rather than local median-nerve compression.

These situations do not necessarily mean the person can never have surgery. They mean the diagnosis or medical condition should first be clarified or optimized.

How is carpal tunnel release done?

Carpal tunnel release is done by dividing the transverse carpal ligament so that pressure inside the carpal tunnel falls and the median nerve has more space. Surgeons can reach the ligament through an open or mini-open palm incision, through an endoscope inserted through small portals, or in selected centres through newer ultrasound-guided minimally invasive techniques.

The underlying goal is the same regardless of the approach: complete and safe decompression of the median nerve.

Step 1: Anaesthesia

Many operations can be performed using local anaesthesia.

The surgeon injects local anaesthetic around the operative area so the patient remains awake without feeling surgical pain. Some centres combine local anaesthesia with light sedation. Regional anaesthesia or general anaesthesia may be appropriate in selected circumstances.

The 2024 AAOS guideline gives strong support to local anaesthesia alone as an appropriate option for carpal tunnel release.

A related approach increasingly used in hand surgery is WALANT—wide-awake local anaesthesia no tourniquet. It combines local anaesthetic with adrenaline/epinephrine to provide anaesthesia and control bleeding without routine sedation or a tourniquet. Evidence supports its use in appropriately selected patients and settings.

The anaesthetic technique should be chosen around the individual patient rather than used as a marketing claim.

Step 2: Positioning and preparation

The patient usually lies on their back with the arm positioned on a hand table or support.

The operative hand and wrist are cleaned with antiseptic solution and surrounded by sterile drapes.

A tourniquet may be used with some approaches to minimise bleeding and improve visualisation. WALANT surgery may avoid the need for a tourniquet.

Step 3: Identifying the carpal tunnel

The surgeon works over the palm and wrist where the transverse carpal ligament lies above the median nerve.

The median nerve must be protected throughout the operation. Anatomical variations in nerve branches, tendons and vessels can occur, which is one reason surgeon training and careful visualisation matter.

Step 4: Releasing the transverse carpal ligament

The surgeon divides the transverse carpal ligament along an appropriate line while protecting the structures beneath it.

Once the ligament is completely released, pressure on the median nerve decreases.

The surgeon assesses whether decompression is complete before closing the skin or finishing the minimally invasive procedure.

Step 5: Closure and dressing

With open or mini-open surgery, the skin is usually closed with sutures and covered with a dressing.

Endoscopic portals are also closed or dressed according to their size and the technique used.

The patient then moves to the postoperative recovery area before discharge.

Open carpal tunnel release

Open release is an established and widely performed technique.

A small incision is made in the palm. The surgeon works directly through the incision, identifies the transverse carpal ligament and divides it while protecting the median nerve.

Traditional open incisions historically tended to be longer, but contemporary mini-open carpal tunnel release uses a smaller palmar incision that does not need to cross the wrist crease in many cases. The AAOS guideline specifically uses “mini-open” to describe this modern smaller-incision approach.

Potential advantages of open or mini-open release

The surgeon has direct access to the ligament and relevant anatomy. The technique is familiar to hand surgeons worldwide and normally requires less specialised equipment than endoscopic surgery.

Modern mini-open surgery can achieve excellent outcomes with a relatively small incision.

Potential disadvantages

The incision lies in the palm, so tenderness around the scar or “pillar pain” can affect pressure-bearing activities during early recovery.

Wound-related symptoms may be somewhat more prominent than after certain minimally invasive approaches, although most settle with time. A contemporary review found open surgery associated with more wound-related problems such as scar tenderness, whereas endoscopic approaches have historically carried more risk of transient nerve disturbance.

Endoscopic carpal tunnel release

Endoscopic carpal tunnel release uses a small camera to visualise the carpal tunnel and the underside of the transverse carpal ligament.

Depending on the system, the surgeon uses one or two small portals. An endoscope is passed into the correct plane, and a cutting instrument divides the ligament under controlled visualisation.

Does endoscopic carpal tunnel release give better results?

Not in terms of established long-term patient-reported outcomes.

The AAOS 2024 guideline found strong evidence of no difference in long-term patient-reported outcomes between mini-open and endoscopic carpal tunnel release.

Some evidence suggests endoscopic surgery can result in quicker early functional recovery or an earlier return to work.

A 2024 umbrella review found a shorter return-to-work interval with endoscopic surgery, while longer-term hand function and symptom outcomes were broadly similar.

A systematic review of randomized trials also found earlier return to work after endoscopic release, by roughly one week on average in the pooled studies.

These averages should not be presented to an individual patient as a promise. Occupation, surgeon protocol, pain, dominant-hand surgery, bilateral surgery and workplace requirements can affect return to work more than the incision type alone.

Risks specific to endoscopic surgery

Endoscopic release requires experience with the equipment and endoscopic anatomy.

Recent literature generally reports low major complication rates, but transient nerve injury has been a concern in comparative studies. A 2024 systematic review found broadly favourable endoscopic results while noting a higher risk of reversible nerve injury in the evidence it evaluated.

The AAOS therefore emphasizes that both approaches should be performed by surgeons trained in the technique they use.

Ultrasound-guided carpal tunnel release

Ultrasound-guided release is a newer minimally invasive approach available in some centres.

Real-time ultrasound allows the clinician to visualise the median nerve, transverse carpal ligament, tendons, vessels and surrounding anatomy while a specialised instrument divides the ligament through a small access site.

Evidence has expanded substantially.

A 2025 systematic review and meta-analysis involving 4,097 patients found meaningful improvement in function and symptoms after ultrasound-guided release. In comparative studies, complication rates were similar to open techniques, while return to work and normal activity tended to occur sooner.

However, a newer 2026 systematic review highlighted important limitations: heterogeneous techniques, relatively small studies, limited long-term follow-up and possible conflicts of interest. It concluded that ultrasound-guided release is promising but that the certainty of current evidence remains limited.

For Orthopedic Abroad, we should therefore describe ultrasound-guided carpal tunnel release as an emerging/minimally invasive alternative, not declare it universally superior to standard open or endoscopic surgery.

Open vs endoscopic vs ultrasound-guided release

The main message should be that the quality and completeness of median-nerve decompression matter more than marketing a particular incision as the universally “best” option.

Carpal tunnel release is usually performed as a day-case procedure, meaning most patients arrive, have the operation and return to their accommodation or home on the same day.

An overnight hospital stay is not routinely necessary for uncomplicated primary surgery. NHS and BSSH patient information both describe standard carpal tunnel surgery as day-case treatment.

Immediately after surgery

The hand is normally covered with a dressing. Depending on the surgeon's technique, this may range from a light dressing to a bulkier postoperative bandage.

Patients are encouraged to move their fingers and thumb rather than keeping the entire hand completely still. Elevating the hand can help reduce swelling during the early postoperative period.

Pain control

Some soreness is expected once the local anaesthetic wears off.

The 2024 AAOS guideline provides strong evidence supporting acetaminophen/paracetamol and/or non-steroidal anti-inflammatory medication for postoperative pain after carpal tunnel release where medically appropriate.

Not every patient can safely take NSAIDs, so medication choice should account for kidney disease, stomach ulcers, anticoagulants, allergies and other medical issues.

Routine opioid medication is generally unnecessary for many uncomplicated procedures.

Discharge

Before discharge, the team confirms that the patient is medically stable and understands:

• wound and dressing care;

• permitted hand movement;

• pain medication;

• warning signs;

• follow-up arrangements;

• work restrictions;

• driving advice.

The patient should have safe transport from the surgical facility.

Patients receiving sedation may have additional discharge restrictions and may need a responsible adult with them according to hospital policy.

International patients

A same-day hospital discharge does not automatically mean same-day international travel is ideal.

The surgeon should confirm when the patient can travel based on wound condition, anaesthesia, pain control, comorbidities and the length of the journey.

Orthopedic Abroad should ensure that an international patient's discharge plan includes written instructions and a route for contacting the clinical team after returning home.

Recovery narrative

Recovery after carpal tunnel release is usually much shorter than recovery after major joint or spine surgery, but nerve recovery and incision recovery happen at different speeds.

Most patients begin moving their fingers almost immediately. Light use of the hand is gradually reintroduced as pain and wound condition allow.

Cambridge University Hospitals advises keeping the hand elevated during the first week, maintaining movement of the wrist, fingers and thumb, and beginning light activities as the wound progresses.

The wound often heals during the first few weeks. NHS decision-support guidance gives approximately 3–4 weeks for full wound healing, although individual healing rates differ.

Numbness and tingling recovery

Patients frequently ask why they may still experience numbness after the ligament has been released.

The answer is that decompression happens immediately, but nerve recovery is biological and can take time.

Night-time tingling may improve in the first days or week. More established numbness may improve over several weeks or months.

AAOS guidance states that patients with severe disease may need 6–12 months for fingertip sensation to improve, and some very severely damaged nerves may never regain completely normal sensation.

This should be discussed before surgery so that gradual neurological recovery is not misinterpreted as an unsuccessful operation.

Grip strength

Grip and pinch strength commonly feel reduced shortly after surgery.

Part of this is related to pain and the healing incision rather than permanent weakness.

AAOS notes that grip and pinch strength commonly recover by approximately 2–3 months, while patients whose median nerve was in poor condition before surgery may need 6–12 months.

Scar sensitivity and pillar pain

Palm tenderness can continue after the incision closes.

Pillar pain describes discomfort around the heel of the palm, often on either side of the released ligament. It can be noticeable when leaning on the palm, pushing out of a chair or gripping firmly.

The American Society for Surgery of the Hand notes that pillar pain is a recognized postoperative issue and generally improves with time.

Scar massage or hand therapy may be recommended in selected patients once the wound has healed adequately.

Routine formal supervised therapy is not necessary for everybody. The 2024 AAOS guideline found moderate evidence against routinely prescribing supervised postoperative therapy after carpal tunnel release.

Patients who develop stiffness, disproportionate pain, persistent weakness or functional difficulty may still benefit from individualized hand therapy.

Returning to work

The type of work matters enormously.

NHS England's decision aid gives approximate return-to-work ranges of:

• 1–2 weeks for desk-based work;

• 2–4 weeks for light manual work;

• 4–8 weeks for heavy manual work.

These are not fixed restrictions.

A patient doing remote computer work with the non-dominant hand operated on may resume some duties much sooner. A construction worker using vibrating tools and heavy grip may require longer.

Endoscopic techniques may shorten early return-to-work time in some populations, but long-term results are similar to mini-open surgery.

Driving

NHS England advises that some patients may not be able to drive safely for about 1–2 weeks because of hand pain and weakness.

The practical requirement is more important than a calendar date.

The patient must be able to:

• grip and steer securely;

• react quickly;

• operate all vehicle controls;

• perform emergency manoeuvres;

• avoid impairment from medication.

Insurance and local legal requirements also apply.

Exercise and sport

Walking and lower-body exercise can usually continue relatively early provided the hand is protected.

Activities requiring forceful gripping, impact through the palm, racquet use, weight training, climbing or contact should wait until the wound and hand are ready.

A surgeon may give different timelines depending on whether the procedure was open, endoscopic or ultrasound-guided and whether the dominant hand was treated.

Flying after carpal tunnel release

There is no single universal evidence-based flight date that applies to every patient.

For international treatment, the sensible approach is to confirm with the operating surgeon that:

• the patient is medically fit to travel;

• the wound is stable;

• pain is controlled;

• no early complication requires review;

• medication and dressings are available;

• follow-up is arranged.

Patients who receive sedation or general anaesthesia may have additional short-term travel restrictions.

The longer and more complex the journey, the more useful it is to avoid scheduling departure immediately after surgery.

Outcomes and success rates

Carpal tunnel release is an effective treatment for appropriately selected patients with symptomatic median-nerve compression, but outcome should be described as improvement rather than a guaranteed cure.

NHS England's patient decision aid reports that roughly 75–92 people out of 100 felt better one year after surgery in the studies used to construct the aid.

AAOS states that surgery improves carpal tunnel symptoms for most patients, although complete recovery can take up to a year.

BSSH similarly reports that surgery usually provides lasting relief, while tingling tends to recover faster than grip strength and severe cases may not regain completely normal nerve function.

What usually improves first?

Night-time tingling and painful pins-and-needles often improve first.

Patients sometimes notice a change almost immediately because mechanical pressure on the nerve has been relieved.

Constant numbness generally takes longer.

Muscle weakness and thenar wasting are the least predictable features because successful decompression cannot instantly reverse chronic axonal loss or muscle denervation.

What determines the result?

Important prognostic factors include:

• severity of nerve compression before surgery;

• duration of symptoms;

• presence of constant numbness;

• thenar muscle wasting;

• age and general health;

• diabetes or generalized neuropathy;

• correct diagnosis;

• complete ligament release;

• previous surgery;

• coexisting arthritis, tendon disease or cervical pathology.

A patient who has waited until the nerve is severely damaged can still benefit from decompression, but the probability of restoring completely normal sensation or strength is lower.

Patient-reported outcomes

Researchers commonly assess carpal tunnel surgery using instruments such as the Boston Carpal Tunnel Questionnaire and QuickDASH.

Contemporary systematic reviews demonstrate clinically important improvement in symptoms and function after both endoscopic and mini-open carpal tunnel release.

For example, a best-evidence synthesis of 17 endoscopic studies involving 1,632 patients reported significant improvements in pain, symptom severity and functional scores after surgery.

A corresponding review of mini-open surgery likewise found clinically meaningful improvements in pain and function.

Open versus endoscopic outcomes

This is an area where marketing frequently becomes stronger than the evidence.

The AAOS guideline gives a strong recommendation that mini-open and endoscopic release do not differ in long-term patient-reported outcomes.

Some endoscopic studies report faster early return to work and less scar discomfort. That difference can matter to selected working patients. However, it should be balanced against cost, availability and technique-specific risk.

A 2026 review of randomized carpal tunnel release studies also cautioned that many statistically significant differences between techniques are based on relatively fragile data, which reinforces the need not to exaggerate small procedural differences.

Persistent or recurrent carpal tunnel syndrome

Symptoms can persist or return after surgery.

Persistent symptoms immediately after surgery can result from severe irreversible nerve damage, incorrect diagnosis or incomplete release.

Symptoms that improve and later recur can have other causes, including scar formation or recurrent compression.

A large cohort analysis found cumulative revision surgery rates around 1.06% at five years and 1.59% at ten years in the population studied, although revision rates vary according to patient population, technique and definition.

A 2025 review of recurrent or persistent disease reported that primary surgery fails in a minority of cases and that published revision rates vary considerably.

Those numbers demonstrate why Orthopedic Abroad should avoid simplistic claims such as “99% permanent cure.”

Does carpal tunnel release use an implant?

Usually no.

Standard carpal tunnel release normally requires no artificial joint, plate, screw, nerve implant or prosthesis.

The procedure works by releasing the ligament that is compressing the median nerve.

This makes the “implants and technology” CMS field somewhat different for carpal tunnel release than for knee or hip replacement.

Open surgical instruments

Mini-open surgery uses standard hand-surgery instruments to expose and safely divide the transverse carpal ligament.

The key technological requirement is not a branded implant but accurate visualization and controlled release.

Endoscopic systems

Endoscopic carpal tunnel release requires:

• an endoscope;

• camera/visualization system;

• dedicated cannulas or portals;

• specialised cutting instruments.

One-portal and two-portal systems exist.

The specific device matters less to the patient than surgeon familiarity and safe technique.

Ultrasound guidance

High-resolution musculoskeletal ultrasound allows direct real-time visualization of the median nerve, ligament, flexor tendons, vessels and surrounding anatomy.

It may be used diagnostically and, in selected centres, to guide percutaneous carpal tunnel release.

Recent meta-analyses are encouraging, but long-term independent comparative evidence remains less mature than for open and endoscopic procedures.

WALANT

Wide-awake local anaesthesia no tourniquet is not an implant or decompression technique. It is an anaesthetic and surgical-setting approach.

Its potential advantages include avoiding sedation or general anaesthesia in suitable patients and allowing efficient outpatient treatment.

AAOS evidence strongly supports local anaesthesia alone as sufficient for many carpal tunnel releases.