Buttock Indentation Pain: Differential Diagnosis and Management

Differential Diagnosis

Condition	Key Features	Diagnosis
Pilonidal cyst/sinus	Natal cleft; pit/sinus; discharge, pain, swelling; young hirsute males	Clinical; US if abscess suspected
Coccydynia	Tailbone pain; worse sitting, rising; trauma, childbirth, idiopathic	Clinical; dynamic X-ray (sit/stand)
Sacroiliac joint dysfunction	Unilateral low back/buttock pain; Fortin finger test; provocation tests	Clinical; diagnostic block
Sciatica / Radiculopathy	Radiating leg pain; dermatomal; +SLR; disc herniation, stenosis	MRI
Gluteal tendinopathy	Lateral hip pain; worse lying on side, stairs; +resisted abduction	Clinical; US/MRI
Ischiofemoral impingement	Deep buttock pain; narrowed ischiofemoral space	MRI
Deep gluteal syndrome	Piriformis syndrome, gemelli, obturator internus; sciatic nerve entrapment	Clinical + MRI neurography

Red Flags

• Night pain, weight loss, fever → infection, malignancy
• Saddle anesthesia, bowel/bladder dysfunction → cauda equina (emergency)
• History of cancer → metastatic workup

Management Principles

• Activity modification, NSAIDs
• Targeted PT: core, gluteal strengthening, neural mobilization
• Image-guided injections (corticosteroid, PRP, hydrodissection)
• Surgery: pilonidal excision, coccygectomy, decompression, SIJ fusion (refractory)

Accurate diagnosis via history, exam, and imaging guides effective treatment.