Minimally Invasive Spine Surgery (MISS)

Minimally Invasive Spine Surgery (MISS) has evolved from a niche marketing term to a standard of care for many spinal pathologies. The philosophy of MISS is not just about a smaller skin incision ("keyhole surgery"), but about minimizing collateral damage to the stabilizing soft tissues of the spine.

Visual Element: Cover image showing the view through a tubular retractor, highlighting the magnified visualization of the nerve root and dura.

The Muscle-Sparing Philosophy

Traditional open spine surgery involves stripping the paraspinal muscles from the spinous processes and laminae. This detachment can lead to muscle atrophy, dead space formation, and postoperative back pain ("fusion disease").

MISS techniques, particularly tubular microdiscectomy, utilize sequential dilators to split the muscle fibers rather than cutting or stripping them. Once the tube is removed, the muscle fibers fall back into place, preserving their function and blood supply.

Visual Element: Internal cross-section graphic comparing the approach of Open vs. MISS surgery. The open side shows muscle stripping and retraction, while the MISS side shows the tubular retractor passing through the muscle fibers.

Tubular Microdiscectomy: The Technique

The tubular microdiscectomy is the workhorse of MISS.

1. Targeting: Fluoroscopy is used to localize the disc level precisely.
2. Dilation: A guide wire is passed, followed by sequential dilators to create a corridor to the lamina.
3. Retraction: A tubular retractor is docked and secured.
4. Microscope: An operating microscope or loupes are used to visualize the anatomy through the tube.
5. Decompression: A laminotomy is performed, the ligamentum flavum is removed, and the disc herniation is excised.

Indications and Limitations

Ideal Indications:

• Far lateral or foraminal disc herniations.
• Single-level spinal stenosis.
• Synovial cysts.
• Obese patients (deep exposure is easier with a tube than a massive open incision).

Limitations/Learning Curve:

• Limited Field of View: The surgeon can only see what is directly under the tube. Navigating to the contralateral side ("over the top") requires technical expertise.
• Dural Tears: Repairing a dural tear through a narrow tube can be challenging.
• Radiation Exposure: MISS relies heavily on fluoroscopy, increasing radiation dose to the surgeon if not managed carefully.

Outcomes

Studies consistently show that while long-term outcomes (pain relief, recurrence) are similar between open and MISS techniques, MISS offers distinct short-term advantages:

• Less intraoperative blood loss.
• Lower postoperative pain scores and narcotic use.
• Shorter hospital stay (often same-day surgery).
• Faster return to work.

Conclusion

MISS is a powerful tool in the spinal surgeon's armamentarium. By respecting the soft tissue envelope, we can achieve the same neural decompression with significantly less morbidity, allowing patients to bounce back faster from surgery.