[Primary results using the mini TightRope for revision surgery for painful proximalisation of the first metacarpal after trapezectomy for CMC-1-osteoarthritis].

AIM The aim of the current study was to review the significance of the TightRope to suspend the first metacarpal in the case of a revision for patients with painful proximalisation after trapezectomy. PATIENTS AND METHOD After an average of 25.5 months (13-60) from initial operative treatment for rhizarthrosis, revision surgery was performed on 6 female patients with a mean age of 56 years, using a Mini TightRope. Before and after revision-surgery the pain level was measured, using the visual analogue scale (1-10) as was the level of strength in the fingertips. The overall result was documented according to the evaluation scale according to Buck-Gramcko. Directly after surgery as well as at the last follow-up exam, the degree of proximalisation of the first metacarpal was radiologically measured. The follow-up period was 13.7 months on average (4-31 months). RESULTS After revision surgery a decrease in pain level was detected, but no patient was completely pain-free. According to the visual analogue scale the pain level after surgery compared to preoperatively was: at rest at an average of 2.5 (1-4), preoperatively 3.3 (2-4); with mild load 3.5 (2-5), preoperatively 4.8 (4-6); and with high load 4.8 (3-7), preoperatively 7 (6-8). The level of strength in the fingertips was postoperatively measured at below 60% in 2 patients (preoperatively 5 patients), once between 60 and 79% (preoperatively 1 patient) and 3 times between 80 and 99%. With an average preoperative score of 11.7 (6-16) points according to Buck-Gramcko, an increase of 20.3 points could be achieved by performing the revision operation. This resulted in a score of 32 (14-44) out of 56 points. The measured distance between the distal scaphoid pole and the centre of the base of the first metacarpal was postoperatively at an average of 8.3 mm (5.6-11.4 mm). The final follow-up shows an average distance of 3.3 mm (2.8-4.3 mm). This is consistent with an average proximalisation of 5 mm. The Mini TightRope had to be removed three times. An additional operation had to be performed twice. CONCLUSION The use of the Mini TightRope for a suspension of the first metacarpal, in cases of a painful proximalisation after trapezectomy is a procedure that can cause an improvement for a certain percentage of patients. But a further proximalisation cannot be prevented by the use of the Mini TightRope.