Prosthetic attachment system

A prosthetic socket system comprising:

• a prosthetic socket arranged to receive a residual limb and defining a distal end, a proximal end, and an axis extending between the distal and proximal ends, the prosthetic socket including a base and at least one longitudinal support connected to the base and distributed circumferentially about the axis;
• a prosthetic attachment system including:
• an insert arranged for connection to a prosthetic liner, the insert defining a circumferential locking groove;
• an attachment unit secured to the base and coaxial with the axis, the attachment unit comprising a body defining a central opening for selectively receiving the insert and carrying a locking element located circumferentially about the axis and radially repositionable relative to the axis;
• and
• a release mechanism slidably repositionable on an outer surface of the body to move the prosthetic attachment system between a locked configuration in which the at least one locking element are radially repositioned to engage the circumferential locking groove and lock the insert in the central opening of the body and an unlocked configuration in which the insert is released from the central opening;
• wherein the attachment unit includes a stop member arranged such that when the prosthetic attachment system is in an unlocked configuration an outer surface of the stop member engages the locking element;
• wherein the body includes at least one resilient member arranged to bias the stop member upwardly within the central opening, the at least one resilient member comprises at least one primary spring member located circumferentially about the axis.