Raw interview notes:
- Tibial guides are all very similar, that is the easier side to do.
- Femoral drilling has 4 different techniques:
- Trans-tibial (most traditional): you drill through the tibia first and then use the tibial tunnel as your guide. Hard to recreate the anatomical position of the ACL with this technique. So mostly outdated now
- Independent portal drilling (anteromedial portal drilling), you drill the tunnel from the knee portal. Use a guide into the lateral knee portal
- Stiff and flexible reamers are used to send pins into the knee, pretty popular methods nowadays
- The guides sits on part of the femur, some have markings for distance or little hooks. You don’t want it too far forward because it leads to laxity, and if you are too far back you blow out the back of the knee
- Saks uses an outside-in guide (flip cutter be arthrex)
- All other methods are inside-out, which doesn’t give you much control about where the exit hole is. With outside-in, you can be very specific about the angles and where you place the tunnel. This reamer uses a retrocutter instead of a forward cutting device like other techniques
- Outside-n guides have to conform to the inside of the knee, must be adjustable in terms of width and sizing and angle, must be stiff enough that you don’t lose your path while drilling
- No drill guides for Lemaire LET
- Saks has not done one in practice, but it is done using freehand drilling techniques and anatomical landmarks
- If we do a drill guide for this, maybe look at how MPFL (medial patellofemoral ligament) reconstructions are done
- Could look up Arthrex’s technique. Can probably do something similar for LET
- Potentially could use an x-ray guide, like a ruler that you put on the side of the knee
- ACLR kit has been so super engineered . . . in the past he might have said that stiffness in the flip cutters was the greatest problem, but that’s sort of been addressed
- How you know you’re placing the guides in the right spot? All guides have this problem. This is probably the biggest challenge, and the guides have been super engineered so there are no real problems here
- This is more specifically for the outside-in guides, since there is no hook onto an anatomical landmark. It’s a lot of eyeballing rn with outside-in drilling techniques
- You need some freedom to move it around, but
- Something built into a guide to give you anatomical landmarks would be great
- If something like that were to exist, what constraints would you need it to have?
- PSI = patient – specific instrumentation: 3D-printed guides made from CT scans of a person’s anatomy exist, this is done a lot for shoulder replacements although it’s less common because it is more expensive. However, nothing like this exists for ACL
- Could print a guide
- Drawback: expensive
- Probably wouldn’t change much, might be a huge pain in the ass but it’s interesting to think about
- So long as you tunnel isn’t way off, how you drill the tunnel really isn’t that important. It turns out well, it’s actually a pretty
- There are issues with ACL but mostly they turn out really well
- LET x-ray technique would be the most viable and actually pretty helpful
- LET is a hot topic right now, people are publishing more about it and it’s the way the wind is blowing even if not many people use it right now
- There are a million ACL guides out there, but none for LET
- Constraints for LET xray thing:
- It needs to be based on radiographic anatomical landmarks
- Schottle’s point: you could use this, people might have published papers on these types of landmarks . . . rn in LET people are just kinda placing them wherever. LET is not anatomic, so it’s not so clear cut. Is there an ideal spot, and does it have a corresponding marking on the xray
- Are there xray studies done to define where to best place the LET
- If so, what landmarks can we incorporate into the guide