Chronic psoas syndrome caused by the inappropriate use of a heel lift
From: J Am Osteopath Assoc. 2008 Nov;108(11):629-30
Heel lifts are commonly recommended for patients to manage the pain and discomfort of leg length discrepancies. However, used inappropriately, orthotics can create additional pain instead of alleviating it. In the case described, a 79-year-old male physician used a recommended heel lift for a perceived leg length discrepancy after right hip arthroplasty. Six months postsurgery, chronic, intractable pain developed in his hip and groin. He underwent a battery of tests to locate the pain, but its source remained elusive. Osteopathic evaluation and radiographic examination revealed an absence of leg length discrepancy and the presence of chronic psoas syndrome. Osteopathic manipulative treatment was prescribed and heel lift therapy discontinued, and the patient reported complete remission from pain.
Leg length discrepancies contribute to myriad conditions in patients, including low back pain, knee pain, and abnormal gait. Such discrepancies, which can occur naturally or postsurgically, can often be resolved through the use of heel lifts. However, used inappropriately, these corrective devices can worsen—or even cause—leg length discrepancies, leading to somatic dysfunction. Although leg length discrepancies have not been reported previously in the medical literature as contributing to psoas syndrome, the current case illustrates the use of inappropriate heel lifts to be a plausible, underlying factor in the occurrence of this chronic condition.
Psoas syndrome can be defined as a muscular imbalance, strain, spasm, tendonitis, or flexion contracture of the iliopsoas muscle (consisting of the iliac and psoas major). This syndrome may result in a number of symptoms including:
- flexion deformity of the leg on the affected side
- increased pain when standing or walking
- lordosis when supine
- nonneutral somatic dysfunction of the lumbar vertebra 1 or 2 (L1 or L2)
- pain in the lower back, pain radiating anteriorly toward the groin, or both
- pelvic shift to the opposite side
- point tenderness medial to the ASIS or femoral triangle
- psoatic gait
- sacral dysfunction on an oblique axis
- spasm of the contralateral piriformis muscle
The most common causes of psoas syndrome are direct muscular dysfunctions arising from iliopsoas spasm or strain. Spasm of the iliopsoas often occurs after a position with a shortened psoas (eg, sitting, kneeling, crouching) has been maintained for an extended period of time. Strain of the iliopsoas can result from forceful contraction of these muscles when the thigh is in a fixed or extended position. For example, this forceful contraction may occur while running uphill, performing straight-legged sit-ups, stumbling with one leg extended, or kicking a ball. In iliopsoas strains, the pain begins as a sharp stab in the groin and increases with active resisted hip flexion or passive external rotation. In adolescents, the injury may produce avulsion of the lesser trochanter; in adults, the result may be a complete or partial tear at the muscle-tendon junction.
Other causes of psoas syndrome include irritation to the psoas muscle directly or through viscerosomatic reflexes. Organic causes of psoas syndrome, some of which may be serious or life-threatening, include abdominal aortic aneurysm, intra-abdominal abscess, appendicitis, diverticulitis, inguinal hernia, prostate or sigmoid colon cancer, prostatitis, salpingitis, ureteral calculi, and Crohn disease.
In the case described, the right sacral base unleveling and right anterior innominate rotation most likely resulted from compensating for the use of an inappropriate heel lift. The innominate rotation lengthened the resting length of the psoas muscle, placing it under constant strain. The onset of the psoas dysfunction probably began during a golf game, when the patient forcefully contracted the iliopsoas with the thigh in a fixed or extended position. This strain in the context of a chronically lengthened psoas initiated the chronic psoas syndrome. As illustrated in the current case, the long-term consequences of compensating for an inappropriate orthotic lift or of actual leg length discrepancy can become deleterious and even disabling.
The diagnosis of psoas syndrome may be elusive because the syndrome can masquerade as many different medical conditions that could distract a practitioner from making an accurate diagnosis. In addition, perceived leg length discrepancies should be carefully interrogated and managed properly. The long-term consequences of compensating for a leg length discrepancy or use of an improper lifting device can have serious, detrimental effects. Further research into leg length discrepancy as a cause of chronic psoas syndrome is recommended. Through conscientious appreciation of symptoms combined with an osteopathic structural examination and contemplating the whole person, the practitioner can facilitate proper diagnosis and treatment.
