**17. Discussion**

During the last 4 decades wrist arthroscopy has turned from the diagnostic tool of some enthusiasts to the widely used therapeutical complex for treatment of different wrist pathologies. Evolution of the wrist arthroscopy equipment as well as skills of the surgeons has allowed us to improve our knowledge of the wrist anatomy and biomechanics. Wrist arthroscopy is especially valuable for evaluation of intra-articular soft tissue pathologies. Furthermore - arthroscopic classification systems have been described for TFCC, SLIL and LTIL lesions, Kienböck disease, 1st CMC joint, etc.

Wrist arthroscopy techniques have proved superiority over the open techniques with lower complication rates and recurrence rates. For example in wrist ganglion surgery open surgical excision had a mean recurrence of 21%, compared with a recurrence rate of 59% for aspiration. The lowest rate was observed with arthroscopic excision, with a recurrence of 6% across all studies [40].

Arthroscopic scapho-lunate ligamentous repair is now considered the less damaging and denervating than open repair [143]. Although several arthroscopic SLIL reconstruction methods as well as arthroscopic reconstruction technique for LTIL tears have been described, these surgeries are challenging, therefore different modalities and variations of open procedures are still actual and used. Some arthroscopic techniques require a long learning curve and years of practice.

A systematic review about arthroscopic vs. open TFCC surgeries shows comparable results between open and arthroscopic procedures, in terms of DRUJ re-instability and functional outcome scores. There is insufficient evidence to recommend one technique over the other in clinical practice [144]. However arthroscopic procedures are less aggressive and may allow quicker recovery, especially in athletes [145]. In combination with a TFCC procedure, the ulnar variance can readily be assessed. Ulnar abutment or impingement can be directly visualized through dynamic

assessment. Whilst ulnar shortening is an extra-articular procedure, the arthroscopic wafer procedure allows for intra-articular treatment without the need for hardware. This overcomes the issues of hardware prominence and circumvents non-union rates of about 10%, while also allowing for a quicker return to work [145, 146].

Wrist arthroscopy is beneficial also in the treatment of distal radius articular fractures, because it helps to visualize articular gaps and step-offs unrecognized with the fluoroscope alone. Although arthroscopically assisted DRF surgeries have superior long-term outcomes in several parameters [76], the advantage of this procedure, however, is the recognition of associated soft tissue lesions which can be prevented if recognized.

The next aspect is professional training and experience of the surgeon. Leclercq et al. in the multicenter study organized by EWAS found that surgeons who perform less than 25 wrist arthroscopies per year have a complication rate of 12.06%, whereas among the surgeons who perform more than 75 wrist arthroscopies per year, the complication rate is 3.95%. Surgeon with less than 5 years of practice in wrist arthroscopy have complication rate 13.6%, whereas surgeons who had 15 or more years of practice complication rate is only 2.3%. Surgeons with longer practice and greater amount of wrist artrhroscopies performed per year, more often are doing therapeutical arthroscopies. This ratio is up to 87% of procedures comparing to less experienced colleagues who perform therapeutical procedures in about 60.5% of cases [147].
