Does it matter how we measure metatarsal length?

• Published in: Foot and ankle surgery Vol. 17; no. 3; pp. 124 - 127
• Main Authors: Chauhan, D., MRCS, Bhutta, M.A., MRCS, Barrie, J.L., FRCS
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.09.2011; Elsevier
• Subjects: Adult; Aged; Aged, 80 and over; Anthropometry - methods; Biological and medical sciences; Diseases of the osteoarticular system; Female; Humans; Male; Measurement techniques; Medical sciences; Metatarsal Bones - anatomy & histology; Metatarsal Bones - diagnostic imaging; Metatarsal measurement; Metatarsalgia; Middle Aged; Orthopedics; Radiography; Reproducibility of Results; Metatarsal measurement; Metatarsalgia; Measurement techniques; Metatarsal bone; Measurement technique; Rheumatology
• ISSN: 1268-7731; 1460-9584
• DOI: 10.1016/j.fas.2010.02.006

Abstract Introduction Variations in the relative lengths of the metatarsal bones have been implicated as a cause of forefoot pain. Osteotomies to balance the metatarsal lengths have been described as therapy. Although measurement of metatarsal length is required for these osteotomies, there is no gold standard method to measure it radiologically. We compared the three main radiological methods to measure the second metatarsal length described in the literature. Materials and Methods Standing dorsoplantar radiographs of 81 feet were measured using the methods described by Coughlin, Maestro and Hardy and Clapham. Bland and Altman's method was used to compare the above techniques for reproducibility and agreement between each method. Results The three methods produced markedly different results. Coughlin's and Maestro's methods showed a relative protrusion of the second metatarsal—relatively longer than the first metatarsal by an average of 4 & 3 mm respectively. Hardy and Clapham's method, however, showed a relative retraction of second metatarsal by an average of 1 mm. Both intra-observer and inter-observer errors were smallest for the Coughlin method (the most reproducible) and largest for the Hardy/Clapham method. Significant lack of agreement was found when we compared the 3 techniques with bias for measuring the mean between methods ranging from 1 mm to 5.5 mm. Conclusions Metatarsal lengths as measured by these three methods can be very variable. Thus their role in planning metatarsal osteotomies and establishing relationship of metatarsal protrusion with metatarsophalangeal joint instability and other similar conditions is questionable and require further studies.