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[Implant arthroplasty in the metacarpophalangeal and proximal interphalangeal finger joints].

BACKGROUND
 Osteoarthritic changes in the finger joints are common, especially in the elderly population. Without adequate treatment, these changes can lead to pain, joint deformity, instability or impaired motion. Operative treatment options can be divided into prosthetic joint replacement, joint fusion and denervation.


PATIENTS/MATERIAL AND METHOD
 During the last decades, various prosthetic implant designs have appeared on the market. This article provides an overview of implant evolution, current implants, clinical results and promising technical novelties.


RESULTS
 Due to favourable clinical long-term results, low revision rates and low costs, the proven silicone spacer has been the gold standard since the 1960 s. In the index and middle finger, lateral stability is crucial to providing a counter bearing to the thumb for a strong key pinch. Medullary-anchored prostheses and modular surface replacement designs have a higher intrinsic stability and may thus be advantageous in the index and middle finger. These implants show promising clinical medium-term results.


CONCLUSION
 In the past, technical novelties from big joint replacements could not automatically be translated to the finger joints and other parts of the hand. However, new trends such as customised or 3D-printed prosthetic implants are slowly beginning to gain importance in hand surgery.