Limb length discrepancy: a new method of measurement and its clinical significance

Methods for assessing leg length discrepancy

The use of accurate and reliable clinical and imaging modalities for quantifying leg-length discrepancy (LLD) is vital for planning appropriate treatment. While there are several methods for assessing LLD, we questioned how these compared. We therefore evaluated the reliability and accuracy of the different methods and explored the advantages and limitations of each method. Based on a systematic literature search, we identified 42 articles dealing with various assessment tools for measuring LLD. Clinical methods such as use of a tape measure and standing blocks were noted as useful screening tools, but not as accurate as imaging modalities. While several studies noted that the scanogram provided reliable measurements with minimal magnification, a full-length standing AP computed radiograph (teleoroentgenogram) is a more comprehensive assessment technique, with similar costs at less radiation exposure. We recommend use of a CT scanogram, especially the lateral scout view in patients with flexion deformities at the knee. Newer modalities such as MRI are promising but need further investigation before being routinely employed for assessment of LLD.

LEVEL OF EVIDENCE

Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Orthotic Management of the Neuropathic Limb

The most common complaint of neuropathic patients is that they were unaware of the neuropathic pathway until it caused a complication. Foot treatment, protection, and amputation prevention historically have been overlooked or covered only slightly in medical education. Chronic neuropathic complications have been seen to have an unavoidable outcome. In many areas, there are no certified orthotists or local health care practitioners who are trained in off-loading techniques. The goal of treatment of a neuropathic or dysvascular patient is to preserve the limb and ambulatory function. Techniques can be shared between disciplines for improved outcomes for neuropathic patients. The combined team expertise with state-of-the-art techniques have enabled wound healing, limb salvage, and improved quality of life for this high-risk population.

Limb length inequality: clinical implications for assessment and intervention

The purpose of this paper is to review relevant literature concerning limb length inequalities in adults and to make recommendations for assessment and intervention based on the literature and our own clinical experience. Literature searches were conducted in the MEDLINE, PubMed, and CINAHL databases. Limb length inequality and common classification criteria are defined and etiological factors are presented. Common methods of detecting limb length inequality include direct (tape measure methods), indirect (pelvic leveling), and radiological techniques. Interventions include shoe inserts or external shoe lift therapy for mild cases. Surgery may be appropriate in severe cases. Little agreement exists regarding the prevalence of limb length inequality, the degree of limb length inequality that is considered clinically significant, and the reliability and validity of assessment methods. Based on correlational studies, the relationship between limb length inequality and orthopaedic pathologies is questionable. Stronger support for the link between low back pain (LBP) and limb length inequality is provided by intervention studies. Methods involving palpation of pelvic landmarks with block correction have the most support for clinical assessment of limb length inequality. Standing radiographs are suggested when clinical assessment methods are unsatisfactory. Clinicians should exercise caution when undertaking intervention strategies for limb length inequality of less than 5 mm when limb length inequality has been identified with clinical techniques. Recommendations are provided regarding intervention strategies.

The prevalence of postural asymmetry in people with and without chronic low back pain

OBJECTIVE

To determine the extent of pelvic obliquity and lateral sacral base angle in subjects with and without chronic low back pain (LBP) by using postural radiographs.

DESIGN

Cross-sectional, controlled.

SETTING

A Veterans Administration hospital.

PARTICIPANTS

Veterans and employees with (n=93) and without (n=76) chronic LBP.

INTERVENTION

Postural radiographs.

MAIN OUTCOME MEASURE

Differences between the mean extent of pelvic obliquity and the lateral sacral base angle in subjects with and without chronic LBP.

RESULTS

The z scores showed no significant statistical differences in the extent of pelvic obliquity or lateral sacral angle in subjects with and without chronic LBP.

CONCLUSION

Correction of pelvic obliquity by the use of heel lifts has been used as a modality of treatment for patients with chronic LBP. The majority of the patients in our clinics for whom this modality is used report at least some improvement in their pain symptoms. Because the extent of pelvic obliquity is similar in the subjects with and without chronic LBP, other factors must account for those who benefit from correction of their pelvic obliquity.

The reliability of postural x-rays in measuring pelvic obliquity

OBJECTIVE

To assess the interrater and intrarater reliability of two methods of measurement of postural radiographs for determining the amount of pelvic obliquity.

DESIGN

Four blinded raters evaluated the amount of pelvic obliquity using two measurement methods.

SETTING

Physical medicine and rehabilitation outpatient clinic in a VA hospital.

PARTICIPANTS

Fifty-two randomly chosen radiographs from 36 patients referred to a clinic to evaluate and treat pelvic obliquity.

MEASURES

Amount of pelvic obliquity was determined by line of eburnation and by the intersulcate line. Pearson's correlation coefficients and percent agreements were calculated for each set of measurements.

RESULTS

Pearson's correlation coefficients and percent agreements were higher for both interrater and intrarater measurements for the intersulcate line.

CONCLUSION

Intersulcate line is the more reliable method for determining the amount of pelvic obliquity and will be used in future studies to assess the effectiveness of correcting pelvic obliquity to improve chronic back pain.

The frontal plane relationship of the forefoot to the rearfoot in an asymptomatic population

Physical therapists use biochemical orthotics to treat symptoms attributed to structural abnormalities of the feet. The purpose of this study was to determine the prevalence of forefoot varus, valgus, and neutral positions in a healthy population, and to compare forefoot positions between genders, legs, and age groups. Nonprobability sampling was used to obtain 120 healthy subjects. A repeated-measures, one-group design was used. A forefoot measuring device and a goniometer were used to measure the forefoot-rearfoot frontal plane relationship. Of the 234 measured feet, 86.67% had a varus, 8.75% had a valgus, and 4.58% had a neutral forefoot-rearfoot relationship. No significant difference in position was found between genders or legs within subjects. A certain amount of forefoot varus or valgus may be characteristic of a healthy population; however, future studies should include children and adolescents to determine if forefoot positions are acquired or congenital.