US Patent 10258378 External bone fixation system

An external bone fixation system may include a first semi-circular external fixation member, a second semi-circular external fixation member, four ball collet assemblies attached to the second external fixation member, and four shafts. Each shaft may include a first end attached to the first external fixation member and a second end with a stop member, and each of the four shafts extends slidably through an opening in a ball of one of the four ball collet assemblies. The stop member of each second end prevents each second end from passing through the opening in its respective ball. Each shaft also includes a hinge located closer to the first end than to the second end.