Alignment and attachment systems for medical instruments

A medical system, comprising:

• a medical instrument configured for use during a robotically-enabled medical procedure, the medical instrument comprising:
• an elongated body extending between a distal end and a proximal end, the distal end configured to be inserted into a patient during a robotically-enabled medical procedure, and
• an instrument handle including a proximal face and a distal face, wherein the elongated body extends through the proximal face and the distal face, wherein the instrument handle comprises a plurality of drive inputs, wherein the distal face is configured to attach to an adapter on an instrument drive mechanism, and wherein the instrument drive mechanism comprises a plurality of drive outputs configured to engage with the plurality of drive inputs;
• and
• an alignment mechanism configured to rotate the instrument handle during attachment of the instrument handle to the adapter to provide rotational alignment between the medical instrument and the adapter, the alignment mechanism comprising:
• a first alignment structure on the medical instrument, wherein the first alignment structure comprises an alignment surface on the elongated body, and
• a second alignment structure on the adapter,
• wherein, as the medical instrument is attached to the adapter, the first alignment structure engages the second alignment structure to provide the rotational alignment such that the plurality of drive inputs on the instrument handle engage with the plurality of instrument drive outputs of the adapter.