Assessment of Chronic Pelvic Pain (CPP) by History and Investigations

Definition

• Affects 12-20% of women in the United States
• Accounts for up to 10% of all outpatient gynecologic consultations, 40% of all laparoscopies, and 18% of hysterectomies
• Up to 70% of women have more than one cause of pain
• Up to 50% have a history of physical, emotional, or sexual abuse

Pathophysiologic Framework

• "Silent" C-fiber nociceptors become activated with visceral tissue injury, flooding the dorsal horn with noxious stimuli
• Dorsal horn neurons develop spontaneous activity, enlarged receptive fields, and lowered firing thresholds
• Pain persists and amplifies even after peripheral pathology resolves - pain is out of proportion to tissue damage
• Allodynia (pain from normally non-painful stimuli) and hyperalgesia (excessive pain from painful stimuli) are characteristic features
• Adverse early experience, conditioning, fear, depression, and anxiety all foster pain persistence

Differential Diagnosis

Assessment by History

1. Pain History - the "OLD CAARTS" Mnemonic

2. System-Specific Symptom Review

• Dysmenorrhea (primary vs. secondary; progressive worsening suggests endometriosis)
• Dyspareunia (superficial vs. deep; deep dyspareunia points to endometriosis, adenomyosis, or ovarian pathology)
• Abnormal uterine bleeding, vaginal discharge
• Subfertility
• Sexual functioning and libido

• Constipation, diarrhea, alternating bowel habit, flatulence
• Hematochezia
• Relationship of pain to altered bowel function and relief with defecation (suggestive of IBS)
• Bloating, abdominal distension

• Urinary urgency and frequency (especially >8 times/day)
• Nocturia, hesitancy
• Dysuria, hematuria
• Incontinence
• Pain that worsens with bladder filling and is relieved by voiding (suggestive of IC/BPS)

• History of physical trauma, surgery, or injury
• Exacerbation with exercise or postural changes
• Weakness, numbness, paresthesias
• Lancinating, electrical, or burning pain (neuropathic quality)

3. Comprehensive Medical, Surgical, and Social History

• Menstrual history: menarche, cycle regularity, flow volume, dysmenorrhea
• Obstetric history: parity, mode of delivery, complications (e.g., pelvic floor trauma)
• Surgical history: prior abdominal/pelvic surgery (increases risk for adhesions), prior oophorectomy (risk of ovarian remnant syndrome)
• Sexual history: STI history, sexual activity, contraception (IUD - risk for PID)
• Medications, alcohol, and recreational drug use
• Prior evaluations for pain with outcome; review prior operative and pathology reports
• Family history: endometriosis, IBD, malignancy

4. Psychosocial Assessment

• Mental health history: prior diagnoses of depression, anxiety, PTSD; hospitalizations; current medications
• Trauma history: past and current emotional, physical, or sexual abuse (up to 50% of women with CPP have a history of abuse; those with trauma history have more severe symptoms)
• Quality of life impact: effects on marital, sexual, social, and occupational functioning
• Behavioral assessment: patient and family attitudes and responses to pain; current life stressors and upheavals
• Suicidal ideation should be directly asked about
• Screen formally using validated questionnaires: the International Pelvic Pain Society assessment tool addresses depression, anxiety, trauma, quality of life, and diagnostic criteria for IBS and IC/BPS

Note: The psychosocial history often requires revisiting over subsequent appointments once rapport is established. Referral to a psychologist should be presented as routine and necessary - not an implication that pain is psychogenic.

Assessment by Investigations

1. Physical Examination (Precedes Investigation)

• Abdominal examination: focal tenderness, guarding, rebound; assess for hernias (inguinal, femoral)
• The Carnett Test: palpate tender abdominal spots while patient raises head or performs bilateral straight-leg raise (tensing abdominal muscles)
  • Pain increases = abdominal wall source (myofascial, nerve entrapment)
  • Pain decreases = visceral/intraperitoneal source
• Lumbosacral assessment: paraspinal tenderness, sacroiliac tenderness, range of motion
• Pelvic examination:
  • Vulvar inspection for signs of vulvodynia or dermatosis
  • Pelvic floor palpation for trigger points and levator spasm
  • Bimanual examination: uterine size, mobility, tenderness, adnexal masses
  • Rectovaginal examination: uterosacral nodularity (endometriosis), posterior cul-de-sac pathology
• While standing: pelvic floor prolapse (cystocele, enterocele)
• Every effort should be made to reproduce the patient's pain during examination

2. Laboratory Investigations

3. Imaging Investigations

• Transvaginal ultrasound (TVUS) is the standard initial imaging modality
• Evaluates uterine size, structure, myomas, adenomyosis features
• Identifies ovarian cysts, endometriomas ("ground-glass" appearance), adnexal masses
• Assesses for hydrosalpinx (suggesting prior PID)
• Doppler TVUS for pelvic congestion syndrome (dilated ovarian/pelvic veins >5 mm, reversed flow)
• If ovarian remnant suspected: clomiphene citrate 100 mg/day for 5-10 days can stimulate follicular development to aid ultrasound detection

• Superior soft tissue resolution for suspected deep infiltrating endometriosis (rectovaginal septum, bladder, bowel)
• Characterization of adnexal masses uncertain on ultrasound
• Useful for adenomyosis (junctional zone thickening >12 mm)
• Evaluation of pelvic floor and lumbosacral pathology

• If urinary calculi, GI pathology (diverticulitis, IBD complications), or malignancy suspected

• Gold standard for pelvic congestion syndrome (demonstrating ovarian and pelvic vein dilatation and reflux)

4. Specialised Investigations

• The most definitive diagnostic procedure for intraperitoneal pathology
• Indicated when non-invasive evaluation is inconclusive and symptoms are disabling
• Findings: endometriosis (15-40% of CPP cases), adhesions (~25%), normal findings in 35-60%
• Endometriosis is a surgical diagnosis - requires histologic confirmation of characteristic lesions
• Laparoscopy is normal in 35-40% of women evaluated for CPP - these patients often have nongynecologic etiologies

• For suspected interstitial cystitis/bladder pain syndrome
• Can reveal glomerulations (petechial haemorrhages) or Hunner's ulcers

• If inflammatory bowel disease or colorectal pathology suspected

• For IC/BPS: frequency-volume chart documents voiding frequency, volumes, and pain timing

• Local anaesthetic injection into tender abdominal wall points can confirm abdominal wall pain (augmented by Carnett test) and differentiate it from visceral pain
• Pudendal nerve block for suspected pudendal neuralgia

• Validated questionnaires: PHQ-9 (depression), GAD-7 (anxiety), PTSD screening tools
• International Pelvic Pain Society comprehensive assessment form
• Formal psychological evaluation as part of multidisciplinary team assessment

Summary: A Practical Approach

HISTORY
  ├── Pain characterization (OLD CAARTS mnemonic)
  ├── System review (GYN, GI, GU, MSK/neuro)
  ├── Gynecologic, medical, surgical history
  ├── Psychosocial & trauma history
  └── Quality of life impact

EXAMINATION
  ├── Carnett test (wall vs. visceral)
  ├── Hernia assessment
  ├── Lumbosacral exam
  └── Pelvic exam (reproduce pain, bimanual, rectovaginal)

INVESTIGATIONS
  ├── BASIC: CBC, CRP, urinalysis/culture, NAAT swabs, β-hCG, Pap
  ├── IMAGING: TVUS first-line; MRI if deep infiltrating disease/inconclusive
  ├── SPECIALISED: Laparoscopy (gold standard for endometriosis/adhesions)
  │                Cystoscopy (IC/BPS), colonoscopy (IBD)
  └── PSYCHOSOCIAL: Validated screening questionnaires, MDT referral