Minimally Invasive Spine Surgery versus Endoscopic Spine Surgery What Do You Need To Know

An ultra-minimally invasive form of surgical treatment for cervical, thoracic and lumbar herniated disc, sciatica(radiculopathy) , spinal stenosis, cervical radiculopathy and/or myelopathy and other spinal conditions leading to pain and disability


What is the difference in terms of technology between open spinal surgery, minimally invasive microscopic and endoscopic spinal surgery

Spinal surgery is offered to patients when patients have unstable spine, compression of nerves and/or deformity of the spine. Patients who have such problems in spine presents with neck/back pain, limbs pain and nerve symptoms such as weakness, numbness , unstable walking , hands cannot function as per normal and /or bladder/bowel problems. Spinal surgeries when performed open typically involves making a 3-10cm cut in the skin, muscles are split apart and burnt with electric generated heat energy (diathermy) and traditional spinal instruments to expose underlying bone and ligaments which are removed to create space around spinal nerves (Decompression). As bones, joints and ligaments are cut or patient has inherent unstable spine, screws and cage are inserted to stabilize the spine in some cases (fusion). Open spinal procedures can be done with naked eyes, microscope or loupes magnification.

The use of endoscope in medicine is not a new concept. Currently, endoscope is widely used and has replaced the traditional open surgery in several general surgical, neurosurgical and orthopaedic surgeries. For example, many sports related injuries are treated with knee arthroscopy rather than open knee repair of torn ligaments. Similarly, when one has a polyp in colon for biopsy, a colonoscopy is performed to remove the poly or biopsy it. Spine surgery is one of the latest subspecialty in Orthopaedic and Neurosurgery which uses endoscope to treat its various conditions.

Endoscopic spine surgery is one of the least invasive version of minimally invasive spine surgery. Some surgeons term it as the bridge between pain procedure and minimally invasive open spinal surgery. (Figure 1)

It involves the use of an endoscope which is a 8-10mm in diameter with 4 functions:

1) Irrigation- the inflow of saline from inflow port constantly washout tissue and blood clots that is required to be removed.

2) Magnification by lens- to improve safety and to visualize nervous tissue clearly.

3) Light source- to provide clear visualization.

4) Working channel – delicate endoscopic instruments can be passed into a small working channel in an endoscope to reach the target disc, bone, nerve region to perform surgery.

Together with enhancement of specialized working instruments and usage of constant inflow and outflow of normal saline into one device is used to reach target site of spinal nerves bypassing the burning and cutting of soft tissues. One or two subcentimeter (7mm-1cm) skin incision is usually all it required to complete the surgery. As the lens is in the front of the endoscope, surgeon does not need to burn all the tissue from the level of skin to bone in order to reach the target site. Surgeon can place endoscope directly to target site by blunt dilation of the soft tissue hence it will decrease pain, blood loss and chance of soft tissue trauma and infection. As it is a sophisticated form of spinal surgery, specialized training and courses are required in order for accreditation to perform such surgery effectively. Latest evidence in literature of endoscopic spine surgery shows good results, safety profile, less blood loss, less infection rate, excellent wound healing, less scars, less back pain and societal cost effectiveness when compared to open spinal surgery.

Figure 1a: using endoscope an visualize the surgery in a TV output system. 1b-d: Various endoscopic equipment which fits the working channel.

What is the difference between endoscopic spine surgery and minimally invasive spine surgery?

Minimally invasive spinal surgery is similar to open spinal surgery in terms of using microscope, diathermy and traditional spinal instruments, however using tube dilation and some specialize devices, muscles can be split rather than burnt and smaller incision is made on the skin. Microscope is placed 30-50cm above the patient in both types of surgery hence tissues from skin to the spinal bone target must be removed /burnt /split so that the surgeon can see clearly through the microscope to decompress spine.

In endoscopic spine surgery, the operation is performed under irrigation. This involves 3 aspects: 1) lens and light can see under normal saline conditions to visualize directly at the target site deep in the spinal canal and not 30-50cm above the skin, 2) constant washing of debris and cooled heat generated during surgery. This decreases charring of soft tissue and inadvertent damage of soft tissue and lower risk of infection. 3) Instruments are passed directly to the target site without traumatizing.

Minimally invasive spine surgery generally required general anesthesia to complete the surgery.Endoscopic spine surgery can be performed under local anesthesia with sedationin selected cases. It can be performed with epidural anesthesia and general anesthesia as well. In some patients who have poor cardiac reserved and cannot undergo general anesthesia, it is good to discuss the surgical options with an endoscopic spine surgeon to assess whether the decompressive surgery can be performed under local anesthesia with sedation.

There is evidence that patients who had undergone endoscopic spine surgery generally will have a shorter hospital stay, less postoperative pain, less blood loss and smaller scar than minimally invasive spine surgery and open spinal surgery. In our experience, most of our patients in our series who underwent endoscopic decompression stayed in hospital for less than 23hours. As a result, we tend to do 1-3 level endoscopic spinal decompression as day surgery.