Back Pain and Minimally Invasive Spine Surgery

written by Dr Harwant Singh on 2 September 2013
Back problems plague everyone at least once a lifetime. It is a common affliction which causes work output to be affected, and increases the cost of health care. The cornerstone in successful management of back pain is to establish a correct diagnosis. This is done by obtaining a relevant history and physical examination; supported by appropriate investigations. Once a diagnosis has been established, appropriate treatment can be suggested.
 
The majority of patients referred for a back specialists’ opinion will have had some treatment already instituted by the referring general practitioner or doctor. These are usually general methods which should settle at least 90% of the patients, and consists of analgesics with some time off work. Some patients will already have had some physiotherapy.
 
The key to a successful treatment rests with a correct diagnosis. This is made with a good history. What is sought in the history are specific patterns of pain. The basic investigations required are plain radiographs of the spine and simple blood tests to exclude infections and inflammations. An MRI of the lumbar spine is routine now because it allows a correct diagnosis to be established without delay; and also provides reassurance if no significant pathology is detected.
 
Usually patients who will have significant benefit from percutaneuous methods will fall into one of the following clinical syndromes;
 
1. Discogenic pain alone : This is a back pain without leg pain. The pains are related to loading of the   
    intervetebral discs and may involve some irritation of the dura. The initial treatment should be a fixed   
    period course of physical therapy. If this does not improve the pain, some invasive methods may be 
    considered.
 
   The Intra Discal Electro Thermal ( IDET ) Therapy is appropriate for this condition as it is minimally  
   invasive. This method allows the spine specialist to apply controlled levels of thermal energy to a broad 
   section of the affected disc wall. Therapy results in contraction or closure of the disc wall fissures or a  
   reduction in the bulge of the inner disc material.
 
   Patients have this procedure done as a day case or with overnight stay in hospital. The procedure is 
   performed in an awake but sedated patient. Back strengthening exercises are conducted the next day 
   and the patients are usually back at work in 2-3 weeks; with a resumption of normal activities in 3 
   months.
 
2. Discogenic pain with radicular component : This is a back pain with leg pain. The pains in the back are 
    related to the discs as in pure discogenic pain, but here there is some irritation of the nerve roots giving 
    rise to the leg pain. Again the initial treatment should be a fixed period course of physical therapy. If 
    this does not have the desired effect, minimally invasive procedures may be considered.
 
   Two procedures may be considered. First is the IDET with a reduction probe, which works on the same 
   principle described before with the only difference being the probe allows for focal disc reduction. The  
   second is a disc decompression by a motorized device which allows some sunction of the disc material 
   causing a reduction in the intra discal pressure. This also provides symptomatic relief.  The post 
   operative regime for both these treatment methods are the same as described before.
 
3. Osteoporotic fractures of the spine : These are usually patients who are in the 80′s and who have 
    multiple medical conditions that render them too frail for any major intervention. They are immobile 
    because of the pain of the fractures of the spine; and deteriorate rapidly usually dying a few weeks 
    after sustaining such a fracture. In the past the prevailing attitude was to allow these patients to ‘die 
    with dignity’; but this has become unacceptable because a safe, quick, minimally invasive procedure 
    under local anaesthesia with mild sedation can restore mobility and decrease incidence of death. 
    Percutaneous vertebroplasty is the procedure of choice for these patients and can be done for multiple 
    level fractures. The patients are encouraged to mobilize the next day, and most achieve a reasonable 
    function of daily living with some independence.
 
4. Mechanical back pain : These occur in patients who have pain usually on movement either forward or 
    backward or side to side. The pains are because of osteoarthritis in the facet joints which cause pain 
    when joints are stressed in these movements. The treatment initially should be in the form of 
    strengthening the back muscles. If this is not possible because movement is difficult, facet blocks with 
    steroids and local anaesthetics can be useful. This is done under local anaesthetics and can be done as 
    a day case. Patients have instant relief, and are able to continue with their daily functions; even back to 
    strengthening their back muscles.
 
5. Radiofrequency (RF) ablation: This is a procedure where the facet joint is denervated by a 
    radiofrequency probe. It is a percutaneous procedure and has very good results in patients who have 
    facet syndrome which has not improved by conventional treatment.
 
6. Nerve root pain from any cause: These patients usually have a radicular type of pain that follows a 
    dermatomal distribution. The diagnosis has to be determined first and methods of non interventional 
    treatment exhausted initially. Selective nerve root blocks can be performed as either diagnostic or 
    therapeutic measures.
 
What is the role of analgesics in back pain?
This is a question that has to be approached with some degree of rationality. Inflammatory causes will benefit from a short course of anti-inflammatory drugs which can be in the form of NSAID’s, COX 2 inhibitors or even steroids. Mechanical pain will only benefit from strengthening back muscles, facet blocks or fusions. Discogenic pain usually does not improve with anti-inflammatory drugs, and an intra discal procedure is indicated. Osteoporotic fracture pain will not improve with any analgesic administration, the fracture has to be addressed for pain relief. If a short course of analgesics have not improved back pain, it is unlikely that long term usage will have any benefit.