What could be causing short periodic pain in the right groin area?

Right Groin Pain: Diagnostic Approach and Common Causes

Your short periodic right groin pain requires systematic evaluation starting with imaging, as the differential diagnosis is broad and includes musculoskeletal, intra-articular hip pathology, referred spinal pain, hernias, and genitourinary causes.

Initial Diagnostic Steps

Plain radiographs of the hip and pelvis should be obtained first to screen for common disorders such as hip osteoarthritis, bone lesions, or structural abnormalities 1. This is the appropriate starting point even though radiographs may be normal in many causes of groin pain 1.

Key Clinical Features to Assess

• Pain location specificity: Deep groin pain suggests hip joint pathology, while superficial inguinal pain points toward hernia or enthesopathy 1, 2
• Pain with hip internal rotation: This maneuver reproduces symptoms in hip joint pathology including osteoarthritis 1
• Antalgic gait or limited range of motion: Indicates significant hip joint involvement 1
• Palpable tenderness at pubic insertion of inguinal ligament: Suggests enthesopathy, a commonly missed cause of chronic groin pain 3

Most Common Causes of Periodic Right Groin Pain

Musculoskeletal Causes (Most Likely)

• Hip osteoarthritis: Presents with groin and lateral hip pain exacerbated by activity and relieved by rest, often with progressive course 1
• Enthesopathy at inguinal ligament insertion: Accounts for a significant proportion of chronic obscure groin pain cases and responds well to steroid injection 3
• Hip labral pathology: Can cause intermittent catching or locking sensations with groin pain 2, 4
• Iliopsoas bursitis: Causes anterior hip and groin discomfort 2
• Adductor or rectus tendinopathy: Common in athletic populations but can occur in non-athletes 2, 3

Referred Pain Sources

• Lumbar spine pathology: Lower lumbar disc herniation (L4-L5 or L5-S1) can cause groin pain transmitted via sympathetic nerves, though less common than high-level disc disease 5
• Sacroiliac joint dysfunction: May refer pain to the groin region 1

Other Considerations

• Inguinal hernia: Must be evaluated with Valsalva maneuver, though often coincidental rather than causative 2, 3
• Genitourinary pathology: Including urolithiasis or urinary tract conditions 1
• Lymphadenopathy: Enlarged inguinal lymph nodes can cause localized discomfort 2

Recommended Imaging Algorithm

If radiographs are normal or non-diagnostic, ultrasound is the next appropriate step for evaluating soft tissue structures, hernias, and hip joint effusions without radiation exposure 1, 2. Ultrasound can effectively assess:

• Hip joint effusion and synovitis 2
• Muscle and tendon pathology including tears and tendinosis 2
• Iliopsoas bursal distention 2
• Inguinal hernias (must be performed with Valsalva maneuver in two orthogonal planes) 2
• Lymph node enlargement 2

MRI without IV contrast should be obtained if ultrasound is non-diagnostic or if intra-articular hip pathology is suspected, as it provides superior soft tissue characterization and can identify labral tears, cartilage damage, and bone marrow edema 1, 4.

Critical Pitfalls to Avoid

• Don't assume a visible inguinal hernia is the pain source: Hernias are often coincidental, and the true cause may be enthesopathy or hip pathology 3
• Don't overlook the pubic insertion of the inguinal ligament: This site of tenderness can be obscured by the pubic fat pad and is a common missed diagnosis 3
• Don't forget dynamic evaluation: Hernias require Valsalva maneuver assessment, and snapping hip syndrome requires dynamic ultrasound 2
• Don't ignore referred pain: Lumbar spine and sacroiliac joint pathology can present as isolated groin pain 1, 5

When Conservative Measures Are Appropriate

For localized tenderness at tendon or ligament insertions (enthesopathy), infiltration with long-acting corticosteroid (1% triamcinolone) and local anesthetic (2% lignocaine) provides effective relief in the majority of cases 3. This approach showed superior outcomes compared to observation alone in patients with chronic groin pain from enthesopathy 3.

For suspected hip osteoarthritis, oral NSAIDs should be used when not contraindicated (strong recommendation), with acetaminophen as an alternative option 1. Physical therapy could be considered for mild-to-moderate symptomatic hip osteoarthritis 1.