I had one of those new back surgeries with the tiny incision. It was supposed to protect my back muscles from all the cutting that goes with an open incision. Well, it didn't work. I ended up with muscle damage and weakness. I thought maybe other people would like to know it's not a 100 per cent perfected yet.
As you have discovered, the good news is that long, open incisions to perform surgery on the lumbar spine (low back area) are no longer needed. New surgical tools and techniques make it possible to complete decompression and fusion procedures with several smaller incisions. This new approach is referred to as minimally invasive surgery (MIS).
The main advantage of the minimally invasive approach is less trauma to the bones, muscles, tendons, and other soft tissues of the spine. There is less bleeding and a faster recovery time. But even so, this technique requires the use of retractors to pull the tissues apart in order to give the surgeon access to the spine.
Even with a smaller incision, there is still the risk of trauma (cutting or crushing) to the soft tissues when using a minimally invasive approach. There is a learning curve that may contribute to problems. Studies show that surgeons have much greater success as their level of experience with this procedure increases. Reports of complications and problems are much higher at the beginning when surgeons are just starting to use this method.
Efforts are being made to find alternative ways to use the minimally invasive approach in order to do away with the kind of complications and problems you experienced. Based on studies done so far, change in location of the incisions (from the middle of the spine to either side of the spine) and safer ways to retract the soft tissues are now advised.
Anything that can be done to reduce trauma to the soft tissues will provide a better result with fewer complications and problems. Patient can still benefit from the minimally invasive procedure without the added loss of spinal stability you had as an unfortunate side effect of the technique.