A minimum of 5-year Folow-up Results of the ARPE prosthesis for painfull degenerative trapeziometacarpal joint. Prof Dr F Stockmans1, Dr Barth J2, Dr Van Haecke J1, Dr Dizillie M1 1: Consultant 2:Resident Handsurgery AZ Groeninge, Kortrijk, Belgium. Orthopedics and Traumatology AZ Groeninge, Kortrijk, Belgium. The purpose of this study was to review our outcome in the treatment of trapeziometacarpal osteoarthritis with a ARPE-prosthesis (Biomet) in patients with a minimum follow up of 5 years. 81 consecutive ARPE-prosthesis for osteoarthritis of the thumb carpometacarpal joint were prospectively reviewed. All patients were operated on by a single surgeon. 70 prosthesis were implanted in women, 11 in male patients. 46 cases were performed on the left side, 35 on the right side. 5 patients had bilateral procedures. Mean age at surgery was 57 years with a mean follow-up of 74,5 months (range: 60105) Five patients were lost to follow up, 12 patients could not come to the hospital for X-ray and clinical examination. For these patients a questionnaire was taken by phone. All remaining patients were reviewed clinically and radiologically by one of the authors. Clinical assessement consisted of VAS for pain, VAS for subjective statisfaction and Quick-Dash questionnaire. Strenght was quantified using a hand dynamometer ( JAMAR, TEC, Clifton, NJ) and a pinch gauge( JAMAR) to measure the lateral pinch. Radiological evaluation was performed with bilateral standard AP en lateral X-rays, as well as a Robert’s view. X-ray’s were compared to preoperative radiological studies if available. We screened for stem or cup loosening, subsidence of the stem and whether or not patients developed ipsilateral STT-arthrosis. Results: After a mean follow-up of 74,5 months patients reported a mean VAS pain: 0 (range 0 – 9) , a mean VAS satifaction: 10 (range 4 -10) and a mean Quick-Dash-score: 4,55 (range 0 – 86,36). Range of motion evaluation showed a mean Postop Kapadji-score of 10 (range 8- 10) a mean postoperatively JAMAR-score: 26 kg vs 26 kg on the contralateral side and a mean postop K-pinch: : 4 kg ipsilateral vs 3,5 kg contralateral . Radiological evaluation at the final follow-up did not show any signs of stem subsidence. Stem loosening was detected in 1 case, Loosening of the cup in 2 cases. Six patients developed ipsilateral STT-arthrosis. Survivalship analysis according to Kaplan Meiers showed 4 failures (failure defined as any reason for arthroplasty revision) which means a survivalship of 94,91 % at 5 years. Two dislocated prostheses were revised to a retentive cup and evolved uneventfully afterwards. In 2 cases with symptomatic STT-arthrosis a trapezectomy was performed.