Development of Unilateral Piriformis Syndrome in a Female with Congenital Leg Length Discrepancy

Abstract

Background: This is a rare case of piriformis syndrome. We discuss the patient's symptoms, imaging study results, laboratory examination findings, and prescribed treatment in an attempt to determine the possible mechanisms or reasons for this patient's development of piriformis syndrome. Methods: The patient is a 22-year-old female soldier who was admitted for lower back pain with soreness radiating to her right buttock and right lower extremity. We found that she had leg length discrepancy under X-ray finding. She was diagnosed piriformis syndrome by physical examination and Magenetic Resonance Image. Results: We performed scanography for lower extremities revealed a left femur length of 42.7 cm, a right femur length of 43.3 cm, a left tibia length of 33.2 cm, and a right tibia length of 33.6 cm; her left lower extremity was 1 cm shorter than her right. The MRI of sacrum also reveals hypertrophy of right piriformis muscle. Conclusions: Piriformis syndrome might be caused by short-term compensation in congenital leg length discrepancy. The patient with leg length discrepancy changed posture when standing, walking, and running. These compensation postures could lead to abnormality position of bones where there is insertion of the muscle.

Piriformis syndrome: a case series of 31 Bangladeshi people with literature review

“…In LLD, the biomechanics between the spine and lower limb is altered, producing a modified gait pattern. According to the literature review, PS can occur both in ipsilateral and contralateral side to LLD [7,24]. In general, an individual with an LLD must step down onto the short limb and vault over the long limb with resultant increase in vertical displacement of the centre of mass and hence increased energy consumption.…”

“…In addition, an individual may shorten the longer leg by increasing pelvic obliquity, circumduction, increasing hip and/or knee flexion, increasing ankle dorsiflexion, or any combination of these owing to minimizing energy consumption. When these are inadequate, the anterior and posterior iliac spines are lower on the side of the short leg, which in turn may result in a sacral base un-leveling [24]. So, a greater amount of pressure is transmitted through the Fig.…”

Síndrome do Piriforme: estado da arte

“…Os 50% restantes estão relacionados a: contusões; golpe concussivo na região pélvica, cirurgia, anormalidades nervosas anatômicas, hiperlordose, anormalidades musculares, hipertrofia, fibrose como resultado de trauma, miosite ossificante 51 , pseudoaneurisma da artéria glútea inferior 52 , paralisia cerebral e artroplastia total do quadril 2 . Além disso, há a perna curta como uma das causas raras de SP isoladamente ou associada com outras causas, haja vista que essa discrepância de tamanho dos membros inferiores altera a biomecânica levando ao estiramento e encurtamento do MP 51,53 .…”