gms | German Medical Science

Objectives/Interrogation: Introduction: Open CMC-1 fracture dislocations is rare injury to the hand and thumb caused by high - energy trauma, such as explosions, thumb entrapments and punch press injuries. It is possible only in case of thenar and first web space laceration. In most cases additional massive injury to the hand and fingers is present whereas narrowing of first web and imobility of the thumb are in danger. Authors would like to point out importance of appropriate treatment for future function of the hand.

Methods: Patients and methods: 7 consecutive cases were reviewed between 2007 and 2018. Etiology were pyrotechnics (4 cases), dog bite (1 case), punch press (1 case) and thumb entrapment by ski lift rope (1 case). In all cases open reposition and fixation of I'st metacarpal and reconstruction of thenar muscles and first web were performed. Additional bone and soft tissues injuries were also reconstructed (2 ray amputations, osteosynthesis of metacarpals and falanges and soft tissue coverage performed) Local care and immediate hand therapy and splinting were part of treatment. Healing period took aproximately 3 months. Thumb opposition, sensitivity and first web space span were evaluated as end result.

Results: Residual adduction contracture of first web space appeared in all cases avarege 45 degree). 6 cases suffered from dysestesia of thumb and all cases had opposition lag (Kapandji 6 in 3 cases, Kapandji 5 in 2 cases and in 2 cases rough grip) but functional hand grip and thumb function were preserved.

Conclusion: open CMC-1 fracture dislocation is part of massive laceration of thenar muscles and first interossus muscle. NC bundles are seriuosly damaged while remain usually in continuity. Serious damage of bones and soft tissues require individualised treatment, specialized aftercare and additional surgical procedures can be expected. Permanent consequences such as web space narrowing, loss of sensitivity and oposition can be expected.