Posterior Lumbar Interbody Fusion (PLIF)surgery is a common treatment for degenerative spinal disorders including spondylolisthesis (slipping of the spine bones), scoliosis, and severe disc degeneration. Spinal surgery is usually considered only after conservative therapies have failed to successfully treat back pain and sciatica (leg pain), and fusions are sometimes recommended following decompression surgery
In this surgical procedure, two or more vertebrae are joined or fused together. Fusion surgeries typically require the use of bone graft to facilitate fusion. This involves packing small amounts of bone between and adjacent to the vertebrae in order to “fuse” them together. The bone graft material works as a bridge or platform that binds or fuses two vertebrae together and promotes new bone formation. This stimulates the growth of a solid mass of bone, and helps in stabilising the spine.
This bone graft, along with intervertebral cages (synthetic implants), will take the place of the intervertebral disc, which is almost entirely removed in the process.This helps to eliminate pressure on nerve roots while realigning the spine. The intervertebral cages maintain disc height and help to fuse the vertebrae together. To ensure this area remains immobilised, screws are inserted into the pedicles and connected to rods, this provides additional stability to the vertebrae being fused together.
Alternative techniques can be used instead of the traditional open PLIF. Newer minimally invasive surgical techniques may be used in selected cases, allowing the surgeon to make smaller incisions and limit the extent of muscle dissection required during surgery. The aim of the minimally invasive approach is to preserve the surrounding musculature for faster recovery and reduced postoperative pain. Some of these can include TLIF or MAS-PLIF
You will be given a general anaesthetic to put you to sleep. A breathing tube (endotracheal tube) will be inserted and you will be given a dose of antibiotics to help prevent infection. You will have an indwelling catheter (IDC) placed to help you pass urine during and after surgery. You will be placed face down on a special operating table and calf compression devices will be attached to your legs. This helps to minimise the risk of developing blood clots in your legs. An X-ray will be taken to identify and mark the level of the spine requiring surgery.
Next, an incision will be made at the level of surgery, and dissection of the muscles in order to expose the bony elements, a retractor is placed to maintain the exposure. The spinous processes and lamina (the bony part forms the back wall of the spinal canal) is removed and any excess bone in the way will be trimmed back to obtain an unobstructed view of the nerve roots. The injured disc, ligaments, bony spurs and any additional material that is compressing the nerves are then removed. This restores room for the nerves that have been compressed, relieving pain and symptoms in the lower back and legs.
Two intervertebral cages containing the graft material are positioned into the intervertebral space to fill the room that has been created when the disc is removed. Screws and rods are then inserted into the pedicles of the vertebra above and below the intervertebral space to maintain spinal stability. Additional bone graft is placed adjacent to the screws. Once complete, imaging is used again to confirm the placement of the spacers and instrumentation. The retractor is then withdrawn, a wound drain is sometimes placed to prevent the formation of a postoperative haematoma, and the skin is closed using absorbable sutures that do not need to be removed. A dressing is applied.
Patients are allowed to mobilise the day after surgery is performed, and you will have a Patient Controlled Analgesia (PCA) device to help manage your pain. A postoperative CT is usually performed to verify position of all the implants. You are usually in hospital for approximately 3-4 days prior to discharge home, or if required to a rehabilitation unit. It is usual to feel some pain after surgery, especially at the incision site. This should decrease a little each day. You will be discharged with pain relief medications to manage this, and given a booklet outlining all postoperative instructions. Once at home you will receive a follow up phone call from the practice nurse. Postoperative appointments will be arranged for you at both the 2 and 6 week mark with the practice nurse and Dr Winder respectively.
Once home, frequent short walks are recommended. This will help in your recovery and also reduces the risk of blood clots forming in your legs. A gradual increase in physical activity is advised.
You must not lift anything heavier than 5kg for the first 6 weeks post-operatively and avoid twisting and bending movements. If bending is necessary, you must bend using your knees and not your back.
Avoid housework such as vacuuming, mowing and hanging washing on the line for the first 6 weeks postoperatively.
Sitting may be the most uncomfortable position postoperatively and should be restricted to 30 minutes at a time in the first week after surgery. You may gradually increase the time in small increments, as you are able.
You may drive 1 week after surgery if you are comfortable to do so but avoid long distances. If you do need to travel for longer periods them make sure you stop and take frequent breaks.
Physiotherapy is recommended 2 to 3 weeks after your surgery. Gentle stretches and core stability exercises will help to strengthen your back after surgery.
Keep your wound dry, you will be given extra waterproof dressings on discharge. You may shower as normal but if your dressing becomes waterlogged it should be changed. Dr Winder’s practice nurse will check your wound at your 2 weeks postoperative appointment. Dr Winder will discuss resuming sports and other physical activity at your 6 weeks appointment
Please note that it is not uncommon to have localised back stiffness for up to 6 weeks. This will generally resolve gradually.
Depending on the degree of nerve compression, it is also very common to have some degree of leg discomfort or numbness, as it will take time for the compressed nerve to recover. Please do not be alarmed if you have some intermittent pain in the legs as this is a normal part of the healing process.It is usual to feel some pain after surgery, especially at the incision site.
RISKS AND COMPLICATIONS
Some of the possible complications for spine surgery include:
- Cerebrospinal fluid (CSF) leak
- Neurological injury
If you require surgery, Dr Winder will discuss all relevant risks during your consultation.
There are risks associated with any surgery, the most common being:
- Deep vein thrombosis (DVT) or Pulmonary embolism (blood clot in lungs)
- Urinary tract infection (UTI)
- Chest infection
- Myocardial infarction (heart attack)
A full medical history including allergies, medical conditions and previous surgery is required before your surgery to help reduce the risk of complications occurring.
Please make sure you bring your scans either on film or on CD on the day of surgery, and inform Dr Winder or his team if you are taking any blood thinners such as aspirin, clopidogrel, warfarin or apixaban.