Symptoms & Diagnosis
|Characteristics of carpal tunnel syndrome
Carpal tunnel syndrome (CTS) is a condition in which the median nerve is compressed so that the patients experience numbness pain and occasionally weakness. The nighttime numbness often causes the patient to wake up and shake their hand. CTS usually progresses slowly over time but the rate varies widely. When the patient has to flex their wrist for an activity i.e. holding a steering wheel or hair dryer numbness can occur.
TypesCarpal tunnel syndrome can be mild moderate or severe. Mild CTS is often causes intermittent numbness. In moderate CTS the symptoms cause frequent nighttime wakening. In severe CTS the patients often notice weakness and they can drop objects without realizing it.
Similar conditionsSometimes a pinched nerve in the neck (cervical radiculopathy) can cause hand numbness and the electrical test (EMG/NCV) can determine if this is present. Hand arthritis can cause hand pain but should not cause hand numbness.
|Incidence and risk factors
CTS is very common with the peak incidence at age 55. Although both men and women can develop CTS the condition is more common in women than in men.
DiagnosisCTS is diagnosed by the patients history physical examination and electrical diagnostic studies (EMG/NCV). The history of nighttime numbness combined with an examination of tenderness over the wrist (Tinel's sign) and increase numbness with wrist flexion (Phalen's sign) help to make the diagnosis. In the Tinel's test tapping the wrist often produces electrical like sensations going into the fingertips. The EMG/NCV is a test performed by a neurologist or physiatrist that measure the speed of nerve conduction. When there is pressure on the nerve the conduction speed significantly decreases.
Not all surgical cases are the same, this is only an example to be used for patient education.
Braces worn at night can be very helpful by decreasing the nighttime numbness and helping the patients sleep. Nonsteriodal anti-inflammatory drugs (NSAIDs) like ibuprofen can help to relieve the symptoms but they do not provide a cure. These medications can be helpful for short-term use but most patients usually do not take these medications on a chronic basis for their CTS because there can be side effects associated with chronic NSAID use.
ExercisesExercises generally do not help because they increase the swelling around the nerve. Rest and bracing provides the best relief. (Figure 4)
Possible benefits of endoscopic carpal tunnel syndromeEndoscopic carpal tunnel release (endo-CTR) releases the pressure on the nerve and restores its normal blood supply. Studies of endo-CTR have demonstrated that patients generally regain their original strength with significant improvement in their symptoms <sup>4</sup> <sup>3</sup>Therapy after surgery can help the patients reduce scar formation and increase their strength. The patients at home usually do these exercises. The patients can return to nearly all activities within several weeks. By three months studies have shown that the patients have recovered to a point where there was no difference in sensation and strength when the hand with CTS was compared to the other hand that had no symptoms.
Types of surgery recommendedCarpal tunnel release is a very reliable surgery. It can be done as an open technique with an incision in the palm or as an endoscopic technique that uses special technology with fiber optic cables and a camera to help the surgeon see the ligament that needs to be released without making a larger incision in the palm. There is one endoscopic technique that requires 2 incisions and one that only requires a single incision. The single incision technique is the only method that avoids an incision in the palm.
Who should consider endoscopic carpal tunnel syndrome?Endoscopic Carpal Tunnel Release is considered when:
What happens without surgery?The numbness with carpal tunnel does not tend to improve and it generally progresses slowly overtime. The rate of change in symptoms can vary. Some patients may develop permanent weakness if the pressure on the nerve is not relieved.
Surgical optionsMost surgeries for CTS release the ligament to take the pressure off of the nerve. Ligament release techniques can be open or endoscopic with a smaller incision. Less common techniques involve stripping the lining off the tendons (synovectomy) or expanding the ligament. Without a release of the ligament there is the problem of the pressure returning.
EffectivenessIn the hands of an experience surgeon the technique can provide permanent relief. It is rare to have to revise the surgery.
UrgencySurgery for CTS is not an emergency. The surgery should be scheduled when the symptoms cause a significant irritation to the patient. Although surgeries can be performed on both hands at the same time if both are significantly affected most patients prefer to stagger the surgeries at least one month or more apart.
RisksThe risks of endoscopic carpal tunnel release include but are not limited to nerve injury infection recurrence of the symptoms tendon injury and scar tenderness. An experienced hand team will use specialized techniques to minimize these risks but cannot totally eliminate them.
Managing riskInfections are extremely rare in carpal tunnel surgery but antibiotics can treat them. Nerve or tendon injury can be treated by surgical repair. Recurrence of symptoms can be treated by revision surgery. In one study of 10 000 consecutive cases of single incision endoscopic carpal tunnel surgery there were no long-term complications that required revision surgery.2
PreparationThere is very little preparation required prior to endoscopic carpal tunnel surgery. The patient should plan on or more weeks off work depending on their type of work. They should plan to minimize the writing and typing for several weeks. They will need to schedule someone to bring them home from surgery.
TimingIn moderate cases the surgery can be delayed until the symptoms of numbness tingling or pain become bothersome. In severe cases a long delay can result in the permanent loss of muscle function.
CostsThe surgeon's office should provide a reasonable estimate of:
Surgical teamAn experienced surgeon who is certified in the technique should perform endoscopic carpal tunnel release. Patients should inquire as to the number of Endoscopic carpal tunnel release procedures that the surgeon performs each year and the number of these procedures performed in the medical center each year.
Finding an experienced surgeonNot every community has a surgeon who is experienced in endoscopic carpal tunnel surgery. Surgeons specializing in shoulder joint replacement may be located through university schools of medicine county medical societies or state orthopedic societies. Other resources include local rheumatologists or professional societies such as the American Society of Hand Surgery.
FacilitiesEndoscopic carpal tunnel surgery is usually performed in a skilled and accredited outpatient surgery unit that routinely performs endoscopic or arthroscopic surgery. They have anesthesiologists nurses and even therapists who are skilled in managing patients with hand surgery.
Endoscopic carpal tunnel release is a highly technical procedure that requires microscopic techniques and the correct endoscopic equipment with the necessary back up equipment. After the anesthetic has been administered a small incision in marked out on the wrist just proximal to the palm. The superficial tendon and small veins are carefully retracted to prevent nerve injury. An 'L' or 'U' shaped incision is made in the first layer called the flexor retinaculum. This layer is lifted up as a flap that forms a doorway into the carpal tunnel. A small spoon shaped device (synovial elevator) (Fig. 5) is used to clean the under surface of the ligament to provide a good view with the endoscope. Dilators help to compress the tissues in the carpal canal to make it possible to insert the endoscopic device with minimal pressure. (Fig. 6) The endoscopic device is inserted carefully so that the ligament can be seen along its entire length. Often the device is warmed to prevent fogging. Once the ligament is clearly seen the small blade in the device is used to release the ligament in stages. After making sure that important nerves and arteries are protected. (Fig. 7) Once the ligament is completely released the rest of the flexor retinaculum in the wrist is release with a special type of scissors. Local anesthetic is injected for post-operative pain relief and the incision is sutured. A soft bandage is applied for the patient to keep on for two days to reduce swelling. After two days they can remove the larger dressing and apply a Band-Aid. They can shower and change the Band-Aid but they should not soak the hand in water such as a sink pool or bathtub until the suture has been removed in about 10 days.
AnestheticMost patients opt for a regional anesthetic called intravenous regional or a Bier Block. They can stay awake for the procedure with or without sedation. The Bier block is very safe and wears off quickly after surgery. They can also choose a general anesthetic. The patient may wish to discuss their preferences with the anesthesiologist before surgery.
Length of endoscopic carpal tunnel syndromeThe actual procedure takes about 30 minutes but the total time for the anesthetic preparation surgery and bandaging takes about one hour. To allow for time for check in and recovery the patients should plan at least a half-day for the surgery.
|Pain and pain management
Endoscopic carpal tunnel surgery is a minimally invasive procedure. The patients often use oral medication after the surgery for a few days. Oral medications include synthetic narcotics such as oxycodone or hydrocodone.
Use of medicationsPatients receive oral and intravenous pain medication in the recovery room. A prescription for oral pain medication is given to the patients at the time that they leave the surgery center.
Effectiveness of medicationsPain medications can be very powerful and effective. Their proper use lies in the balancing of their pain relieving effect and their other less desirable effects. The patients often advance to Tylenol or ibuprofen within a day or two.
Important side effectsPain medications can cause drowsiness slowness of breathing difficulties in emptying the bladder and bowel nausea vomiting and allergic reactions. Patients who have taken substantial narcotic medications in the recent past may find that usual doses of pain medication are less effective. For some patients balancing the benefit and the side effects of pain medication is challenging. Patients should notify their surgeon if they have had previous difficulties with pain medication or pain control.
Hospital stayThe patients are usually monitored for an hour in the recovery area. Instructions for office appointments post-operative instructions and pain medication are provided. The patients are escorted out of the surgery center by a family member or friend.
Recovery and rehabilitation in the hospitalThe patients are encouraged to change their bandages to a small Band-Aid two days after surgery. About 10 days after surgery their sutures are removed and a therapy program is reviewed with them with instructions for them to take home. Patients are advised to avoid heavy activities for about a month after surgery.
Can rehabilitation be done at home?
RisksThis is a safe rehabilitation program with little risk.
Duration of rehabilitationThe patients should follow their instructions for stretching strengthening and scar massage for about two weeks.
Returning to ordinary daily activitiesThe patients can drive within a day or two after surgery. The can cover the bandage with plastic bag to shower for the first two days and then change the bandage and use a small Band-Aid. They can do limited typing and writing within a week after surgery and advance as dictated by their symptoms. Within a month after surgery most patients have returned to all activities. Some patients notice that there strength and sensation improves for three months for certain activities such as opening tight jars or bottles.
Long-term patient limitationsThere no long term limitations after endoscopic carpal tunnel surgery.
Summary of endoscopic carpal tunnel syndrome for carpal tunnel syndromeEndoscopic carpal tunnel surgery is a very successful surgery to restore patient comfort and relieve symptoms of numbness tingling and weakness that can affect activities and sleep.
In the hands of an experienced surgeon endoscopic carpal tunnel release is highly effective with a low rate of complications. Proper diagnostic work up with physical examination and EMG/NCV can insure that the procedure is done for the correct indications.