Mini open transverse flexor crease incision better than longitudinal palmar incision for carpel tunnel release

Traditionally, three different surgical techniques have been described in the literature for carpal tunnel release - the classic or standard open approach, endoscopic approach and limited incision approach.

The standard open carpal tunnel release is often criticized for a higher incidence of scar tenderness, unaesthetic wound healing, scar length, pillar pain, and delayed return to work affecting the quality of life.

Fazil et al compared the outcomes of carpal tunnel release using the limited longitudinal palmar incision technique and mini open transverse flexor crease incision technique and found that Mini open transverse flexor crease incision is better than longitudinal palmar incision for carpel tunnel release.

They performed Carpal Tunnel release procedures on 122 consecutive patients with unilateral idiopathic CTS (carpal tunnel syndrome). Patients in Group A (64 patients) had a palmar mini open longitudinal incision at wrist. Patients in Group B (58 patients) had a small flexor crease transverse incision.

In the mini transverse flexor crease incision technique (group B), a short 1.5–2 cm transverse incision was made at the distal crease of the wrist midway between flexor carpi radialis (FCR) and flexor carpi ulnaris (FCU) tendons. Palmaris longus tendon was identified and retracted radially. The antebrachial fascia was incised exposing the proximal edge of the flexor retinaculum. A 5-mm longitudinal incision was made with a no.15 scalpel on the proximal edge of the flexor retinaculum, revealing the median nerve. After identifying the proximal end of retinaculum, saline is injected between the nerve and retinaculum to clear the adhesions using blunt tipped syringe. A narrow dural retractor is passed underneath the flexor retinaculum gently and felt at the distal end of retinaculum. This maneuver creates a space between the nerve and retinaculum.

Using a blunt ended face lift scissors, the transverse carpal ligament was released till its distal end. The scissors are directed towards the third intermetacarpal space, gradually cutting the flexor retinaculum until the tissue resistance suddenly gives way indicating complete division of the ligament. The dural retractor was placed under the retinaculum to protect the median nerve.

Complete release the flexor retinaculum is confirmed by feeling the lack of fascial resistance felt earlier above the dural retractor along the whole length of flexor retinaculum. The tactile perception of TCL getting incised by the surgeon is of paramount importance to avoid overshooting beyond the ligament and damaging neurovascular structures. A blunt tipped artery forceps was inserted into the carpal tunnel to ensure completeness of decompression.

The preoperative and postoperative (2 weeks,6 weeks,3 months, 6 months and 1 year) patient statuses were evaluated with the Boston Carpal Tunnel Syndrome Questionnaire (BCTSQ) scores, VAS, grip strength and return to work days.

Results:

• The mean surgical time in group A was 24.4 min where as in group B it was 18.5 min (p value < 0.05).

• The BCTSQ symptom severity scale and functional status scale showed significant improvement following surgery in Group B compared to Group A at 2 weeks,6 weeks and 3 months (p < 0.05). At 6 months and 1 year follow up, both the symptom severity and functional status scale were comparable in both the groups.

• Subjects in the transverse incision group returned to work earlier than the palmar incision group (20.26 days compared to 27.06 days) which was found to be significant (p < 0.05).

• Grip strength, palmar pillar pain and scar tenderness showed significant improvement in transverse flexor incision group compared to longitudinal palmar incision group at 6 weeks and 3 months and were comparable later on.

• there were no incidence of tendon, vascular, or nerve injuries in both the groups. None of the patients in either group demonstrated features of palmar sensory cutaneous branch (PSCB) or thenar motor branch of median nerve injury.

 Advantages :

• This technique is useful for CTS release in obese patients where its easy to find the median nerve proximally at wrist without going through the thick palmar fatty tissue.

• The tourniquet is rarely needed as there is minimal bleeding from the wrist incision.

• Can be converted into a open technique if need arises.

 Limitations :

It is not advisable in non-idiopathic and revision carpal tunnel cases which demands the classical open procedure.

The authors concluded that the mini open transverse flexor crease incision technique using the conventional instruments is simple, safe and cost-effective mode of treatment of idiopathic CTS when compared to the limited palmar incision technique. Though the long term outcomes are comparable in both groups, the flexor crease transverse incision group patients had better pain relief, better cosmesis and shorter recovery period than the palmar incision group.

Further reading :

Mini-open transverse flexor crease incision versus limited longitudinal palmar incision carpal tunnel release: A short term outcome study

V.V. Muhammed Fazil , Sibin Surendran , Raju Karuppal , Patinharayil Gopinathan , Anwar Marthya

Journal of Orthopaedics

https://doi.org/10.1016/j.jor.2021.11.017