[Collateral ligament injuries of the metacarpophalangeal joints].

Collateral ligament injuries of the metacarpal joints of the fingers are rare conditions. The injury should be diagnosed by clinical investigation and standard radiographs. Leading symptoms are local tenderness and joint instability. Instability is verified by clinical stress testing of the metacarpophalangeal joint in 90° of flexion. In Grade I injuries stability is preserved due to ligament attenuation or small partial tears. Grade II injuries show laxity with firm endpoint according to incomplete tear. In Grade III injuries instability without endpoint can be found as a result of complete tears. Radiographs may show avulsed bone fragments.In Grade I and II tears or non- displaced avulsion fragments treatment is conservative with buddy taping for 6 weeks. In case of persistent instability or grade III tears suturing or refixation of the ligament are performed. Small avulsion fragments are removed and the ligament is fixed to the bone. Greater avulsion fragments are fixed by suitable small implants. Adequate treatment will lead to reliable good results. Even in chronic tears reconstruction with local material or tendon transplants is usually successful.