The transforaminal approach is less traumatic, but has anatomical restrictions craniocaudally.

The interlaminar approach has wider application craniocaudally, but is more traumatic.

So whenever possible, I would prefer transforaminal approach, unless it is technically not possible by anatomical restrictions.

Anatomical restrictions for the transforaminal approach:

*With foraminal or extraforaminal pathology: No limits.

*With disc herniation within the spinal canal (central or paracentral): Limits: from the caudal edge of the cranial pedicle to the middle part of the caudal pedicle.

*With lateral recess stenosis: Limits: from the caudal edge of the cranial pedicle to the cranial edge of the caudal pedicle

*For central stenosis by dorsal pathology: Cannot be applied.

*L5-S1 pathology in a male with high iliac crest: Cannot be applied, except with iliac crest drilling.

*L5-S1 cranially migrated disc: Cannot be applied.

Anatomical restrictions for interlaminar approach:

*Far lateral pathology (foraminal and extraforaminal pathology): Cannot be applied.

*An exception is foraminal pathology in contralateral interlaminar approach.

General preferences for disc herniation:

* L5-S1 disc herniation: interlaminar approach is preferred, especially if axillary.

* High degree of disc migration: interlaminar is preferred, and sometimes mandatory.

* Above L4-L5: transforaminal is preferred, but with good planning to avoid visceral injury.

* Large central prolapsed disc: transforaminal is preferred, to avoid neural retraction.

* Foraminal prolapsed disc: transforaminal is preferred.

* Extraforaminal prolapsed disc: transforaminal is mandatory.

General preferences for stenosis surgery:

* Central stenosis by dorsal pathology: interlaminar is mandatory.

* Pure lateral recess stenosis: interlaminar is preferred.

* Combined lateral recess stenosis and foraminal stenosis: transforaminal is preferred.

* Pure foraminal stenosis: transforaminal is preferred.

* Foraminal stenosis in L5-S1 in male with high iliac crest: contralateral interlaminar approach.

Conclusion:

I tried my best to summarize the transforaminal and interlaminar approaches. Please correct me if I have any mistake, and add to my summary if you have any addition.