**5. Wrist arthroscopy portals**

The map of safe wrist arthroscopy portals was first designed by Terry L. Whipple and co-authors in 1986 after anatomical studies of fresh cadaveric wrists which were arthroscoped an then tediously dissected to determine the relationship of each portal to the closest neurovascular and tendinous structures [3]. Seven dorsal wrist portals were identified - five portals for radio-carpal joint with relation to the six extensor compartments (1-2; 3-4; 4-5; 6R and 6 U), one for midcarpal joint – distally from the 3-4 portal and the seventh portal for DRUJ. Anatomical studies proved that 1-2,6 U

and 6R portals are the most perilous due the proximity of the radial artery and dorsal radial and ulnar sensory nerve branches. The midcarpal, 3-4,4-5 and DRUJ portals are relatively safe, since neurovascular structures are usually remote [9]. Later additional portals for midcarpal and radio-carpal joint, DRUJ as well as portals and techniques for small joint arthroscopy were described [9–14].

Localization of portals first has to be checked by palpation with fingertip, then standard intramuscular injection needle can be inserted to determine the exact orientation of the portal. Small and shallow horizontal incisions using no. 15 blade are recommended. Then skin, subcutaneous tissues and join capsule can be dissected using mosquito clip to push away any important structures without injuring them. It's suggested to use a curved mosquito clip which can easily slip over the curve of the dorsal rim of the radius or proximal carpal bones.

The normal inclination of the dorsal radius and lunate must be taken into consideration when entering the joints with trocar and never use sharp trocars. The insertion angle usually is about 10° proximally to parallel of the dorsal joint axis, to match the distal articular curves of the bones (**Figure 6**).

Volar portals can be used for visualization of the dorsal capsular structures like dorsal radiocarpal ligament (DRCL), palmar aspects of the carpal ligaments or as occasional accessory portals in arthroscopic assisted surgeries of the distal radius fractures or carpal injuries [13–15].

Localization, function of radiocarpal portals and structures at risk are presented in **Table 1** and for midcarpal portals in **Table 2**.

**Figure 6.** *Insertion angle of the instruments.*


*APL –* m. abductor pollicis longus*, DRCL –* dorsal radio-carpal ligament*, ECRB –* m. extensor carpi radialis*, ECRL –* m. extensor carpi radialis longus*, ECU –* m. extensor carpi ulnaris*, EDC –* m. extensor digitorum communis*, EDM –* m. extensor digiti minimi*, EPL –* m. extensor pollicis longus*, FCR –* m. flexor carpi radialis*, DRF – distal radius fracture, LTIL – luno-triquetral interosseus ligament, SLIL - scapho-lunate interosseus ligament,TFCC – triangular fibrocartilage complex, VR – volar radial portal, VU – volar ulnar portal.*

#### **Table 1.**

*Radiocarpal portals.*


*APL –* m. abductor pollicis longus, *ECRB –* m. extensor carpi radialis*, ECRL* – m. extensor carpi radialis longus*, EDC*  m. extensor digitorum communis*, EDM –* m. extensor digiti minimi*, EPL –* m. extensor pollicis longus*, MCR – midcarpal radial portal, MCU – midcarpal ulnar portal, STT - scapho-trapezio-trapezoidal portal, STT-R - scaphotrapezio-trapezoidal radial portal.*

**Table 2.** *Midcarpal portals.*
