24.1 Description

Endoscopic carpal tunnel release (eCTR) is a minimally invasive surgical technique developed as an alternative to open carpal tunnel release (CTR).

24.2 Key Principles

As with most procedures, excellent visualization is critical. The blade should only be elevated if and when there is acceptable visualization of the undersurface of the transverse carpal ligament (TCL) with no nerve interposition. Moreover, complete release must be achieved in order to ensure optimal outcomes.

24.3 Expectations

Similar to open CTR, the benefit of eCTR lies in its ability to stop the progression of symptoms, with the hope that the symptoms will fully resolve. Night-time symptoms tend to resolve immediately. Patients with mild to moderate CTS, who experience intermittent symptoms, often have early resolution. In contrast, patient with severe CTS, who experience constant numbness and/or thenar weakness, have a more guarded prognosis with a more prolonged recovery.

In comparison to open CTR, eCTR has the additional potential benefit of decreasing the severity of early palmar pain and shortening the time until return to work by 1 to 2 weeks. ^{1 , 2} However, eCTR has an increased incidence of transient neuropraxia (1-2%). ^{3 , 4} Overall, the long-term results seem to be equivalent between the two techniques.

24.4 Indications

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  Symptomatic CTS that has failed nonoperative treatment with splinting and/or corticosteroid injections.

  
  
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  Symptomatic CTS that has evidence of thenar denervation.

24.5 Contraindications

There are no absolute contraindications for eCTR. Due to the concern over visualization secondary to scarring, some surgeons consider revision surgery a relative contraindication. Other surgeons have had good results with revision endoscopic CTR. ⁵

24.6 Special Considerations

Historically, eCTR was believed to result in an increased risk of neurovascular injury. However, more recent studies have refuted this belief. ^{3 , 4} Overall, both open and endoscopic CTR have a similar, extremely low-rate of irreversible nerve injuries (< 0.5%).

24.7 Special Instructions, Positioning, and Anesthesia

The patient is placed on a well-padded operating room table with the affected upper extremity on the hand table. While the procedure can be done with any method of anesthesia, it is typically performed under local anesthesia with or without sedation. Following induction of anesthesia, a pneumatic tourniquet is placed on the proximal arm and set at 250 mmHg. The procedure can be done off tourniquet, but a bloodless field does aid in visualization. Even when using local anesthesia alone, most patients tolerate the use of a tourniquet for a short period of time. If eCTR is performed under local anesthesia alone, the patient is prepared that they may feel pressure or electricity when the synovial elevator and/or endoscope are inserted.

Equipment necessary:

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  Endoscopic equipment including devise and blade (per various manufacturers).

  
  
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  Endoscopy tower/monitor.