What is Vertebroplasty ?
- This is a relatively new technique in the pain relief clinic for people presenting with back pain from an acute vertebral collapse (Wedge fracture). It involves identifying the affected vertebra, and injecting bone cement (methyl methacrylate polymer) into the centre of the vertebral body. Once set, the cement gives the vertebra extra strength, and can produce relatively rapid pain relief.
What are the symptoms of an acute vertebral collapse ?
- Acute localised back pain and Referred Pain to other areas of the body depending on the vertebral level affected. Commonly affected sites in the spine are between T10 and L2, and in the mid-thoracic region.
What are the causes of an acute vertebral collapse ?
- Osteoporosis caused by post-menopausal hormonal imbalance, long term steroid medication, kidney failure, or those on long term bed rest,
- Vertebral haemangiomas (benign blood vessel tumours),
- Secondary cancer deposits (less common).
What are the relevant Examination findings and Investigations ?
- Percussion Test - the affected vertebra can usually be identified by gently tapping over the spinous process whilst lying in the face down position,
- Lateral X-rays may show vertebral wedging,
- MRI Scans can help differentiate between an osteoporotic collapse, haemangioma, and secondary cancer.
What are the Indications and Contra-indications for Vertebroplasty ?
- The main indication for vertebroplasty is vertebral collapse caused by osteoporosis, haemangioma, or secondary tumour. The procedure is contra-indicated in those who cannot lie flat on their stomachs for more than 30 minutes (e.g. severe lung disease), and those with an increased bleeding tendency.
- Vertebral Anatomy
- The Procedure is performed under intravenous sedation , local anaesthesia, and using X-ray guidance.
- After confirming the correct vertebra to be treated, a bone biopsy needle is inserted through the skin, passing through one of the vertebral pedicles, and onwards into the front third of the vertebral body. X-ray contrast medium is injected to check that the needle is not in a large vein.
- Bone cement (methyl methacrylate polymer) is then injected slowly under X-ray fluoroscopy, again checking that the cement is not being injected into a large vein.
- The cement hardens in about 15-30 minutes to provide support to the affected vertebra, thereby producing pain relief.
- Aftercare - bed rest for about 2 hours is followed by progressive gentle ambulation. If pain relief is good then discharge from hospital is possible with simple analgesics by mouth.
- Pain relief is usually achieved in 90% of those with osteoporosis and haemangiomas, and in about 70% in those with secondary cancer.
- Complications occur in approximately 3% of those with osteoporosis, 5% of those with haemangiomas, and in 10% of those with secondary cancer of the vertebra.
- The most common complications are:-
- Rib fracture - due to the downwards forces involved whilst inserting the bone biopsy needle
- Irritation of adjacent spinal nerves whilst inserting the bone biopsy needle
- These usually resolve spontaneously in a few weeks
- Rarely occurring complications include:-
- Pneumothorax (punctured lung)
- Fracture of the pedicle
- Bone cement embolus - cement is carried by large veins through the heart and into the lung
- Spinal cord compression causing paraplegia
- Increased back pain
- Spread of the cement to other soft tissues around the vertebra
- Needle track infection