Pain Joint

What is Interventional Pain Management (IPM)?

· Interventional Pain Management are some minimally invasive procedures which gives permanent/long term pain relief.

· It fills the gap between pharmacologic management of pain & more invasive operative procedure.

According to definition: The discipline of medicine devoted to the diagnosis and treatment of pain and related disorders by the application of interventional techniques (Minimally invasive procedures including percutaneous precision needle placement, with placement of drugs in targeted areas.) in managing sub-acute, chronic, persistent, and intractable pain, independently or in conjunction with other modalities of treatments.

What are the types IPM?

· It may be either diagnostic or therapeutic.

Diagnostic IPM (background):

· Evening in 1990s most of medical textbooks/ journals wrote like these:

1. In as much as 90% of LBP, the source & pathologic mechanism are not known. 1,2

2. There is poor correlation between pathology & clinical findings in spinal pain. 3,4

3. Psychological factors & central pain factors are the main reasons for these poor co-relations.
(References:

1. Hart LG, Deyo RA, Cherkin DC. Spine 20:11, 1995

2. Delitto A et al. Phys Ther 73:216, 1993

3.Waddell G. Spine 21:2820, 1996

4.Ito M, Incorvaia KM, Yu SF. Spine 23:1252, 1998)

· But the picture is radically changing in the new century:

1. A large proportion of patients with LBP develop secondary depression.

2. Nociceptive pain source can regularly be identified in these patients of LBP.

3. Successful treatment of pain may revert the abnormal psychological profiles to normal.

(Reference: Waldman SD. Interventional pain management. 55-57, WB Saunders, 2nd Edition 2001)

What is diagnostic IPM?

1. These are procedures where local anaesthetic drug is injected into the nerves supplying the suspected anatomical source of pain. The volume of drug should be minimum so that it does not spill to other structures and it should be injected precisely at the target. If the pain is relieved, the source of pain from that anatomical structure is confirmed.

2. With the help of Diagnostic IPM, we can diagnose approximately 90% cause of low back pain.

3. Primary psychological causes of low back pain are rarely seen, most of the psychological changes are secondary to unrelieved pain.

With the diagnostic IPM the main causes of low back pain are identified as follows:

1. 15-45% - Facet joint pain.

2. 15-40% - Discogenic pain from internal disc disruption and degeneration. (without disc herniation/ prolapse)

3. 10-15% - Nerve root irritation without mechanical compression.

4. 3-5% - Nerve root compression due to disc herniation/ prolapse.

5. 15-40% - Sacro-iliac joint pain.

6. <2%>

List of Diagnostic IPM done commonly:

1. Selective nerve root block

2. SI joint block

3. Sympathetic Nv. Block

4. Differential spinal/epidural block

5. Diagnostic Facet joint block

6. Provocative discography

7. Epidurogram

8. Spinal endoscopy