Rescue of failure of fibrous interposition arthroplasty with Maia prostheses in CMC arthritis C. Martinez Andrade, M Cruz, O Escudero, MC Castro, JM Morell, F Castillo  Hospital Dos de Maig, Barcelona, Spain INTRODUCTION The fibrous interposition arthroplasty is a technique widely implanted for the treatment of CMC arthritis, normally associated with good results, however, rescue of a fibrous interposition arthroplasty in the treatment of CMC arthritis is a delicate situation, different techniques have been described, most of them using suspension systems such as the mini tigth-rope (Arthrex), on the contrary the use of prostheses is not it is widespread and most of the literature refers to clinical cases. We present a rescue case of Burton-Pellegrini arthroplasty with a Maia prosthesis (Lepine) with good clinical-radiological results CLINICAL CASE Woman of 75 years of age, rizarthrosis surgery in 2004, fibrous interposition arthroplasty and metacarpo-phalangeal arthrodesis, correct clinical evolution until casual fall in August of 2014, radiological study discards fracture, treatment is performed with orthosis and physiotherapy. The patient does not improve, on the x-ray it is observed impaction between the scaphoid and the first metacarpal, it is not corrected with distraction of the thumb (Figure 1) The patient reported severe pain (8 on the VAS scale) and a decrease in the strength of the thumb pinch Surgery was performed in March 2016, Maia (Lepine) prosthesis placement placing the metacarpal component in the first metacarpal and the trapezium dome in the distal pole of the scaphoid (Figure 2,3,4) (Video 1) Fig 2: scaphoid hole for the trapezium dome Fig 3: trapezium dome in place Fig 4: Maia prosthesis, final placement After immobilization for 4 weeks, the patient starts physiotherapy, in her last control, the patient reports a slight pain (2 on the VAS scale), performs correct opposition of the thumb (Kapandji 9) (Figures 5,6), and has improved her thumb clamp strength. The radiological study (Figure 7,8) and the CT (Figures 9,10) objectify a correct placement of both components. Fig 5. Thumb opposition 1,5y after surgery Fig 6. Thumb extesnion 1,5y after surgery DISCUSSION The arthroplasty of fibrous interposition in a habitual technique in the treatment of theCMC arthritis with successful results, is infrequent the necessity of revision by failure being this revision surgery difficult. Normally the rescue is performed with suspension systems to recover the length of the thumb again and avoid the impingement between scaphoid and first metacarpal or between the bases of the first and second metacarpal. The use of prostheses is very unusual, having been described using the stem in the scaphoid and the dome at the base of the first metacarpal, we have not found in the literature reviewed the use of the dome in the scaphoid as in our case. The short time of evolution forces us to be cautious about this type of rescue surgery BIBLIOGRAPHY De Smet L, Vandenberghe L, Degreef I. Long-term outcome of trapeziectomy with ligament reconstruction and tendon interposition (LRTI) versus prosthesis arthroplasty for basal joint osteoarthritis of the thumb. Acta Orthop Belga. 2013 Apr;79(2):146-9 Gangopadhyay S, McKenna H, Burke FD, Davis TR. Five- to 18-year follow-up for treatment of trapeziometacarpal osteoarthritis: a prospective comparison of excision, tendon interposition, and ligament reconstruction and tendon interposition. J Hand Surg 2012 Mar;37(3):411-7 3. Salem HM, Davis TR. Degenerative change at the pseudarthrosis after trapeziectomy at 6-year followup. Clin Orthop Relat Res. Relat Res. 2014 Apr;472(4):1160-5 Fig 1: preop x ray   Distal Video 1: intraoperative ROM X-Ray 1,5y after surgery CT 1,5y after surgery