Scaphoïdectomie distale pour arthrose STT, résultats à court terme — la valeur du DISI mise en question

Abstract

Isolated symptomatic scaphotrapezio-trapezoid arthritis forms an important differential diagnosis in basal thumb pain. Due to the relatively high complication ratio of the conventional STT-arthrodesis and the weakness of thumb strength reported after trapezial excision, emphasis in research has swung towards distal scaphoid resection with or without interposition. In 2009, Decramer and Le Viet described a proper reproducible technique, using Flexor Carpi Radialis tendon as a spacer. Currently, discussion regarding outcomes and complications of this type of interposition procedure needs the most attention. Dorsal Intercalated Segment Instability deformity described after STT-excision doesn’t always seem to correlate with the patients functional ability after surgery and we could ask ourselves whether DISI really matters. All patients with isolated symptomatic STT arthritis that have undergone the above-mentioned technique, between 2012 and 2018, were included. Clinical, radiographical and patient-based written outcome measures were obtained during postoperative visits. We used the operative technique as described in a poster presentation at the FESSH in Poznan in 2009 by Decramer and Le Viet (Institut de la Main, Paris). It involves a distal scaphoid resection, followed by the harvesting of half of the split FCR, which is then accordion like, seated into the freed-up space. The clinical evaluation comprises of range of motion as well as strength measurements. Different relevant carpal angles and the scaphoid length are measured on front and lateral radiographs and compared to the contralateral wrist. Written scores entailed a qDASH, a PRWE score, a VAS pain and a VAS daily functionality of the hand. Twenty-one cases have been evaluated. One patient had wound infection. Three patients suffered from persistent wrist extension deficit, for which 1 patient had revision surgery. Six patients developed CTS complaints. A mild DISI deformity was seen in the majority of the patients. No evolution to gross midcarpal instability was observed. Our results are comparable to earlier studies and report a global satisfactory outcome. Although a mild DISI deformity was seen in the majority of the cases, there was no correlation with the functional scores. This should be interpreted with caution given the relatively short follow-up period. Given the encouraging results of this type of intervention, this operative technique is considered successful in the short term. This study set-up could be used to develop a prospective protocol in order to offer a higher level of evidence with larger series and a longer follow-up period.