Anterior Lumbar Interbody fusion (ALIF) is a type of spinal fusion where the incision to reach you spine is actually made through your tummy. This differs from many of the more conventional surgeries such as the TLIF/PLIF where the approach is through the back. The reason you have been recommended to undergo an ALIF related procedure will be based on your clinical presentation and medical history.
Why you may need it
The spine is made up of individual vertebra (below left) stacked on top of one another and held tyegother by a series of soft tissues including muscle and ligament. The spine is split into 3 main areas those being the cervical (neck), the thoracic (middle) and lumbar (lower back). The type of surgery discussed here is related to the lumbar area of the spine.
The primary reason for fixation or fusion of the spine is to Stablise the vertebrae. That is not to say that an unstable spine will mean you suddenly fall apart, it just means that there is suffient localised movement to irritate the surrounding tissue. This may be soft tissue or nerve tissue and can present in a wide range of symtpoms from local back pain to nerve related leg pain.
In surgical fusions where the incision is made through your back, the spinal anatomy makes it very difficult to reach through to the large vertebral body at the front. In PLIF/TLIF surgery an area of bone must be cut away in the lamina but because the spinal cord runs through the center you always have to work around a corner. This is satisfactory where one or two smaller cages will be sifficient to fuse, but if a more substantial prostheisis is deemed necessary, the only way to safely insert this is through a frontal approach.
ALIF surgery can have several permeatations. A single cage can be inserted in isolation, a cage can be inserted as part of a 360 fusion where the back of the spine is also fused with a rod and screw mechanism the same as in the PLIF/TLIF surgery or a stand alone version of the cage can be used (STALIF). The latter two are more common nowadays and can be seen below:
The most obvious difference between the ALIF cage and the STALIF cage is that the latter has screws integrated into its design. This means it is more stable from the outset than the ALIF cage in isolation ensuring rehabilitation can occur at the earliest stage. Historically a rigid body brace is worn post operatively for a period of time but the introduction of this Stand alone cage has significantly reduced the need for this. A pictue of a STALIF cage can be seen centre below and the two X-Ray images show it in place.
When compared to other types of fusion, anterior surgery has far less information relating to it. This is likely to be a direct reflection of fewer numbers of these being performed. There are a few links below to sites that may give you further information. There is also a very amateur powerpoint show that gives you a basic idea of how the cage is inserted. You will need to have a powerpoint programme of 2007 or newer to be able to view it properly.
Surgical Outcomes
This chart showsthe outcomes for Anterior based surgery between MAy2007-May 2008. Although this may intially seem like a long time ago to allow an audit covering one year, there needs to be a complete year after the latest surgery to allow the annual check up. The vast majority of these cases are STALIF in nature.
Be fore the surgery we take a ‘Pre-Operative’ score of your Disability and this is then followed up at 3,6 and 12 months, and in some cases at two years. This score allows up to catagorise you into subcatagories of Minimal, Moderate, Severe, Crippled or Bedbound. This chart demonstrated the mean likely scaroe that you will obtain at your followups dependant on how disabled you were prior to surgery. This is of course taken across many patients so some individuals will vary however this is an average guide.
