 None of the carpals ( wrist bones ) fit together precisely , suggesting the presence of a large amount of cartilage in the wrist , which would have stiffened it . All of the digits were able to <unk> ( bend backwards ) until they nearly touched the wrist . When flexed , the middle digit would converge towards the first digit , while the third digit would twist inwards . The first digit of the hand bore the largest claw , which was permanently flexed so that it curved back towards the underside of the hand . Likewise , the middle claw may have been permanently flexed , while the third claw , also the smallest , was able to both flex and extend . 
