What are the signs and symptoms of left piriformis syndrome?

Signs and Symptoms of Left Piriformis Syndrome

Left piriformis syndrome is characterized by buttock pain that radiates down the back of the affected lower limb along the sciatic nerve path, often resembling sciatica, due to compression of the sciatic nerve by the piriformis muscle. 1

Key Clinical Features

Pain Characteristics

• Buttock pain extending from the sacrum to the greater trochanter on the left side 2
• Pain radiating down the posterior aspect of the left leg along the sciatic nerve distribution 1, 3
• Pain aggravated by prolonged sitting 3
• Pain worsened by specific hip movements, particularly flexion, adduction, and internal rotation 2
• Pain may be described as dull, aching, sharp, or electrical in character 4

Physical Examination Findings

• Tenderness on direct palpation of the piriformis muscle in the buttock region 2, 3
• Piriformis tenderness on rectal or pelvic examination 2
• Pain reproduction with specific provocative tests:
  • Flexion, adduction, and internal rotation (FAIR test) of the hip 3
  • Freiberg sign (pain with passive internal rotation of the extended thigh) 3
  • Pace sign (pain with resisted abduction of the thigh while sitting) 3
• Normal neurological examination in most cases, with negative straight leg raising test 3
• Possible weak hip abductors on the affected side 2
• Pain on resisted hip abduction in the sitting position 2

Sensory and Motor Symptoms

• Paresthesia (abnormal sensations like tingling or numbness) along the sciatic nerve distribution 1
• Symptoms may mimic those of L5-S1 disc lesions, but typically without the specific neurological deficits associated with true radiculopathy 5
• Unlike true radiculopathy, piriformis syndrome usually does not cause specific dermatomal sensory loss or myotomal weakness 4

Distinguishing Features from Other Conditions

• Absence of low back pain as the primary complaint 2
• Normal spinal range of motion 3
• Normal straight leg raising test (unlike disc herniation) 3
• Normal reflexes (unlike radiculopathy) 3
• Symptoms exacerbated specifically by activities that engage the piriformis muscle 2
• Pain specifically localized to the buttock region with radiation 1

Associated Findings

• Possible leg length discrepancy 2
• May have concurrent myofascial involvement of related muscles 2
• May coexist with lumbar facet syndromes 2
• In long-standing cases, patients may develop compensatory gait patterns 4
• Symptoms may appear suddenly after activities involving back stretching or trauma 4

Diagnostic Challenges

• Diagnosis is primarily clinical as no specific investigations have proven definitive 2
• MRI may show enlargement of the piriformis muscle with anterior displacement of the sciatic nerve in some cases 6
• Electrodiagnostic studies are typically normal but help exclude other causes 7
• The condition is often misdiagnosed due to symptom overlap with lumbar radiculopathy and other causes of sciatica 1, 4
• Estimated to account for 5-6% of cases of low back, buttock, and leg pain, and up to 17% of patients with chronic low back pain 7

Understanding these specific signs and symptoms is crucial for accurate diagnosis of left piriformis syndrome, as it is often overlooked or misdiagnosed as lumbar radiculopathy or other causes of sciatica.