- Screw-Rod-Hook Construct
- Buck Screw Repair
First of all, who is indicated for surgical treatment of lumbar spondylolysis (also called pars defect or pars fracture)? Nonsurgical treatments, such as physical therapy, bracing, activity limitation, injections are the primary interventions. These can be done for as long (months to years) as the patient is functioning at an acceptable level and has and acceptable level of low back pain. If nonsurgical treatments have not been successful, then surgery can be indicated.
What is the main goal with this surgery? Simply it is long-term relief of the low back pain.
In order to achieve the goal of surgery bony healing across the pars region is necessary. The two areas on the above CT scan show the area which is broken (red arrows). This is like have a broken arm or leg. If there is not bony healing it is likely there will not be long-term pain relief. The metal can stabilize the broken area for a short period of time, but will either break or loosen in the bone if it doesn’t heal bone-to-bone.
So, which of the above surgical techniques is optimal?
A large, meta-analysis study by Mohammed et al published in Neurosurgical Focus in 2018 evaluated 46 studies which included 900 patients. The project looked at 4 different metal constructs:
Buck Screw
Scott Wiring
Morscher hook
Pedicle Screw-Hook construct
The conclusion of their project was:
- Bony fusion rates were the highest in the Pedicle Screw-Hook Construct at 90%, in second place with the Buck Screw at 84%
- Complication rate was the lowest in the Pedicle Screw-Hook Construct at 12%, followed by Buck Screw at 13%
Hence if we want the highest rate of bony healing and the lowest complication rate, then the Pedicle Screw-Hook construct is optimal.
Be aware, proponents of the Buck Screw will advocate this technique can be done through smaller incisions (which is true), with less blood loss (not true), shorter hospitalizations (not true), and faster recovery (not true).
I have seen the outcomes of other surgeons using Buck Screw technique and have had to revise them due to the failure to achieve bony healing and persistence of pain. SEE BELOW
My goal is to get bony healing to provide long-term pain relief. A shorter surgical scar is not worth a lower healing rate.