Chronic Abdominal Wall Pain and ACNES .pptx

Abdominal wall as asource of pain

1. No 1 : CAWP SYNDROME DR : Abdel Rahman A Mokhtar Internist @ NWAFH The Missed Diagnosis Series

2. Introduction : Diseased organs are frequently identified as the source of chronic abdominal discomfort and pain. If a patient’s history, physical examination, and diagnostic evaluations are not abnormal, a common functional abdominal pain diagnosis, such as irritable bowel syndrome (IBS), which has a 10% to 15% prevalence in Europe and North America, may be considered. In contrast, the abdominal wall and pelvic floor often are neglected as a cause of chronic abdominal pain and discomfort.

3. CAWP : Chronic abdominal wall pain syndrome.

4. Definition

5. Why CAWP ? Therefore, clinicians worldwide require education on abdominal wall pain problems so that these clinical entities will be identified at an earlier stage and treated accordingly. It is not surprising that doctors’ delay in diagnosing CAWP syndromes is substantial and many patients with ACNES remain undiagnosed. This situation is not only a Dutch issue; CAWP is a globally undervalued medical problem and a diagnostic challenge. [ Van Assen etal., 2013 ]

6. Pathophysiology of CAWP Myofascial pain and radiculopathy are rare examples of a CAWP syndrome. However, CAWP is commonly caused by the entrapment of an anterior cutaneous branch of one or more thoracic intercostal nerves.

7. Locations where pain in the abdominal wall might originate : Locations where pain in the abdominal wall might originate. Epigastric hernias occur along the linea alba. Spegelian hernias occur below the arcuate line where the inferior epigastric vessels traverse the fascia. Nerve roots passing through or around the lateral edge of the rectus sheath are often subject to irritation.

8. The thoracoabdominal nerves, which terminate as the cutaneous nerves, are anchored at six points : 1) The spinal cord; 2) The point of the posterior branch origin . 3) the point at which the lateral branch originates. 4) the point at which the anterior branch makes a nearly 90° turn to enter the rectus channel; 5) the point from which accessory branches are given off in the rectus channel. 6) skin. Pathophysiology of ACNES :

9. The most common site of nerve entrapment is the lateral border of the rectus muscle. Patho physiology of ACNES : At these points the anterior twigs of the intercostal nerves penetrate the rectus abdominal muscle (T7– 12). The level of the umbilicus corresponds with intercostal nerve T10. The most typical site is T11 on the right side.

10. Patho physiology of ACNES : After turning at a 90º angle, the nerve passes from the posterior sheath of the abdominal wall muscle (rectus abdominis ) through a fibrous opening and then branches at right angles while passing through its anterior sheath. It has been thought that the underlying problem is nerve compression with resulting ischemia or lack of blood supply, explained by the nerve's course through the muscle. The entrapped nerve may also be pushed by intra- or extra abdominal pressure or pulled by a scar causing pain in the abdominal wall

11. CLINICAL PRESENTATION General features of musculoskeletal abdominal wall pain

12. Symptomatology of ACNES 1 Symptoms of ACNES can be acute or chronic. The acute pain is described as localized, dull, or burning, with a sharp component (usually on one side) . Radiating horizontally in the upper half of the abdomen and obliquely downward in the lower abdomen. The pain may radiate when the patient twists, bends, or sits up. Lying down may help but sometimes worsens the pain. Young women often express concern about their“ovaries,” “kidneys” or both. Noting that between 30% and 76% of diagnostic laparoscopic procedures done for pelvic pain show normal tissues, Slocomb ( 1984) expressed concern about surgical exploration with removal of pelvic structures for normal variants in women with chronic pelvic pain when the problem was actually traceable to the abdominal wall.

13. Symptomatology of ACNES 2 Chronic complaints due to ACNES are ACNES-related pain is well localized and usually affects only one side. However, the pain can occur on both sides at the same level . or at different levels. Pain radiating into the scrotum or vulva suggests involvement at the T12/L1 level, but inguinal or femoral hernia and pain arising from the adductor muscles of the thigh must be ruled out.

14. Symptomatology of ACNES 3 Pain radiating from T11 and T12 runs at an oblique angle and follows the course of these nerves. Such pain can suggest urolithiasis; however, patients with urolithiasis are usually seen writhing in pain, where as patients with ACNES tend to lie quietly on the table with their hand placed over the area of discomfort. T11 involvement on the right side may suggest appendicitis, and involvement on either side may suggest ovarian involvement or spigelian hernia; all these conditions should be identified by proper physical examination.

15. Symptomatology of ACNES 4 Pain on the right side at the T8 or T9 level may suggest cholecystitis or peptic ulcer ; Chronic ACNES patients suffer considerable anxiety and worry that they may have some horrible condition as yet undiscovered. As a result, they may be given a psychiatric diagnosis (eg, anxiety, somatization, or depression) and therefore often take antidepressant drugs , tranquilizers, muscle relaxants, or pain relievers. Such a medical history should raise the question of ACNES. N.B : Other things such as nausea, bloating, overeating, and menstruation can make pain worse by causing congestion of blood vessels and further nerve compression . Oral contraceptives and pregnancy have also been reported to increase abdominal wall pain, probably from hormone induced tissue swelling

16. Physical Examination 1 Superficial tenderness : Often extreme tenderness upon gentle stroking or pinching in that area of the skin. The patient may guard the area from light touch, sometimes by seizing the examiner's hand. . The pain may extend backwards and up to the vertebral body if its origin is related to nerve root in the spinal cord. The pain may be exacerbated by conditions that can cause nerve pressure or traction, such as coughing , straining , tight clothing, obesity or post-operative scarring. Relief may be obtained by sitting, lying or relatively frequently by hand-splinting the affected area.

17. Often Localised the pain & tenderness? The patient usually responds by placing several fingers over the area, where upon the examiner says, “Show me with one finger.” As patients place a fingertip on the exact spot, pushing a little harder to find it, they usually say, “Right here!” and flinch as the tender spot is pressed. Physical Examination 2

18. Physical Examination 3 Carnett's Sign When pain arises from an intra abdominal source, the tensed muscles in the abdominal wall guard the underlying bowel, thus reducing the discomfort (negative test). However, when the pain arises from the abdominal wall, the muscle contraction will accentuate the pain (positive test)

19. Physical Examination 3 Carnett's Sign N.B : Sometimes, intra abdominal disease with involvement of peritoneum (membrane lining of the abdominal cavity) may give a false positive Carnett test. It is also not very useful to apply this test to individuals with wide spread abdominal pain rather than localized area of pain to avoid misdiagnosis. This test has been found to be sensitive and specific, in one study saving on average $ 900 per case on unnecessary investigations. ( GreenBaum & Joseph ,1994)

20. DIAGNOSIS OF CAWP

21. ACNES questionnaire A VALIDATED QUESTIONNAIRE WITH THE ANSWER KEY. A 10-POINT CUTOFF VALUE RESULTS IN AN OPTIMAL 94% SENSITIVITY AND 92% SPECIFICITY .

22. A highly suggested history can be confirmed by : Physical Examination Superficial tenderness. Localised tenderness Positive carnett`s Sign Response to local anaesthetic A significant (> 50%) pain relief after an accurately placed nerve block or trigger point anesthetic injection is considered confirmatory of CAWP diagnosis. Sharpstone et al (1994) concluded that a successful injection after a positive Carnett sign (to diagnose CAWP) "must be one of the most cost effective procedures in gastroenterology"

23. A highly suggested history : It is important to recognize that the presence of CAWP does not always rule out an existing intra abdominal source of pain and misdiagnoses have been reported. For example, Thompson et al noted that 4 of 62 (6%) patients diagnosed with CAWP were later found to have an intra-abdominal cause of pain . Gray et al reported that 5 of 53 (9.4%) patients with positive Carnett test actually had appendicitis . Of interest, one study also demonstrated the presence of irritable bowel syndrome and functional dyspepsia (indigestion) in 29% and 11% of patients with CAWP, respectively ( Langdon , 2002).

24. MANAGEMENT

25. The management of CAWP depends on the severity of symptoms. In cases of mild pain, minimizing activities that aggravate the pain may be sufficient. An abdominal binder may be useful if gentle hand pressure helps ease the pain. Local nerve blocks or trigger point injections using anesthetic/steroid injections are the treatment of choice for patients with moderate to severe abdominal wall pain. Drugs for neuralgic pain ?????

26. Conclusion When patients present with persistent or recurrent abdominal pain it is all too easy to consider a visceral source and overlook other origins for their symptoms. Patients with chronic abdominal pain are often subjected to a variety of procedures in an attempt to find a cause: simple investigations may give way to more complex and invasive ones in the pursuit of ever more obscure diagnoses. Then failure to find a visceral cause for the pain may prompt the physician to apply a functional or psychosomatic label to the patient . An awareness, however, that abdominal pain may have a non-visceral origin' can forestall a fruitless search for intra-abdominal pathology. A careful history and examination, and being alert to the possibility of the symptoms arising from outside the abdominal cavity, should permit an accurate diagnosis to be made, appropriate treatment given, and an ever downward spiral of yet more negative investigations avoided.