Daniel K Moon1, Christina A Gurnett1, Hyuliya Aferol1, Marilyn J Siegel1, Paul K Commean1, Matthew B Dobbs1. 1. Departments of Orthopaedic Surgery (D.K.M., C.A.G., H.A., and M.B.D.), Pediatrics (C.A.G.), Neurology (C.A.G.), and Radiology (M.J.S. and P.K.C.), Washington University School of Medicine, 1 Children's Place, Suite 4S-60, St. Louis, MO 62110. E-mail address for M.B. Dobbs: dobbsm@wudosis.wustl.edu.
Abstract
BACKGROUND: Clubfoot treatment commonly fails and often results in impaired quality of life. An understanding of the soft-tissue abnormalities associated with both treatment-responsive and treatment-resistant clubfoot is important to improving the diagnosis of clubfoot, the prognosis for patients, and treatment. METHODS: Twenty patients with clubfoot treated with the Ponseti method were recruited for magnetic resonance imaging (MRI) of their lower extremities. Among these were seven patients (six unilateral cases) with treatment-responsive clubfoot and thirteen patients (five unilateral cases) with treatment-resistant clubfoot. Demographic information and physical examination findings were recorded. A descriptive analysis of the soft-tissue abnormalities was performed for both patient cohorts. For the patients with unilateral clubfoot, we calculated the percentage difference in cross-sectional area between the affected limb and the unaffected limb in terms of muscle, subcutaneous fat, intracompartment fat, and total area. With use of the Wilcoxon signed-rank test, we compared inter-leg differences in cross-sectional areas and the intracompartment adiposity index (IAI) between treatment-responsive and treatment-resistant groups. The IAI characterizes the cross-sectional area of fat within a muscle compartment. RESULTS: Extensive soft-tissue abnormalities were more present in patients with treatment-resistant clubfoot than in patients with treatment-responsive clubfoot. Treatment-resistant clubfoot abnormalities included excess epimysial fat and intramuscular fat replacement as well as unique patterns of hypoplasia in specific muscle groups that were present within a subset of patients. Among the unilateral cases, treatment-resistant clubfoot was associated with a significantly greater difference in muscle area between the affected and unaffected limb (-47.8%) compared with treatment-responsive clubfoot (-26.6%) (p = 0.02), a significantly greater difference in intracompartment fat area between the affected and unaffected limb (402.6%) compared with treatment-responsive clubfoot (9%) (p = 0.01), and a corresponding higher inter-leg IAI ratio (8.7) compared with treatment-responsive clubfoot (1.5) (p = 0.01). CONCLUSIONS: MRI demonstrated a range of soft-tissue abnormalities in patients, including unique patterns of specific muscle-compartment aplasia/hypoplasia that were present in patients with treatment-resistant clubfoot and not present in patients with treatment-responsive clubfoot. Correlations between MRI, physical examination, and treatment responsiveness may aid in the development of a prognostic classification system for clubfoot. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
BACKGROUND: Clubfoot treatment commonly fails and often results in impaired quality of life. An understanding of the soft-tissue abnormalities associated with both treatment-responsive and treatment-resistant clubfoot is important to improving the diagnosis of clubfoot, the prognosis for patients, and treatment. METHODS: Twenty patients with clubfoot treated with the Ponseti method were recruited for magnetic resonance imaging (MRI) of their lower extremities. Among these were seven patients (six unilateral cases) with treatment-responsive clubfoot and thirteen patients (five unilateral cases) with treatment-resistant clubfoot. Demographic information and physical examination findings were recorded. A descriptive analysis of the soft-tissue abnormalities was performed for both patient cohorts. For the patients with unilateral clubfoot, we calculated the percentage difference in cross-sectional area between the affected limb and the unaffected limb in terms of muscle, subcutaneous fat, intracompartment fat, and total area. With use of the Wilcoxon signed-rank test, we compared inter-leg differences in cross-sectional areas and the intracompartment adiposity index (IAI) between treatment-responsive and treatment-resistant groups. The IAI characterizes the cross-sectional area of fat within a muscle compartment. RESULTS: Extensive soft-tissue abnormalities were more present in patients with treatment-resistant clubfoot than in patients with treatment-responsive clubfoot. Treatment-resistant clubfoot abnormalities included excess epimysial fat and intramuscular fat replacement as well as unique patterns of hypoplasia in specific muscle groups that were present within a subset of patients. Among the unilateral cases, treatment-resistant clubfoot was associated with a significantly greater difference in muscle area between the affected and unaffected limb (-47.8%) compared with treatment-responsive clubfoot (-26.6%) (p = 0.02), a significantly greater difference in intracompartment fat area between the affected and unaffected limb (402.6%) compared with treatment-responsive clubfoot (9%) (p = 0.01), and a corresponding higher inter-leg IAI ratio (8.7) compared with treatment-responsive clubfoot (1.5) (p = 0.01). CONCLUSIONS: MRI demonstrated a range of soft-tissue abnormalities in patients, including unique patterns of specific muscle-compartment aplasia/hypoplasia that were present in patients with treatment-resistant clubfoot and not present in patients with treatment-responsive clubfoot. Correlations between MRI, physical examination, and treatment responsiveness may aid in the development of a prognostic classification system for clubfoot. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Authors: David M Alvarado; Hyuliya Aferol; Kevin McCall; Jason B Huang; Matthew Techy; Jillian Buchan; Janet Cady; Patrick R Gonzales; Matthew B Dobbs; Christina A Gurnett Journal: Am J Hum Genet Date: 2010-07-09 Impact factor: 11.025
Authors: David J Gerlach; Christina A Gurnett; Noppachart Limpaphayom; Farhang Alaee; Zhongli Zhang; Kristina Porter; Melissa Kirchhofer; Matthew D Smyth; Matthew B Dobbs Journal: J Bone Joint Surg Am Date: 2009-06 Impact factor: 5.284
Authors: David M Alvarado; Kevin McCall; Jacqueline T Hecht; Matthew B Dobbs; Christina A Gurnett Journal: J Med Genet Date: 2016-01-04 Impact factor: 6.318
Authors: Brooke Sadler; Gabe Haller; Lilian Antunes; Momchil Nikolov; Ina Amarillo; Bradley Coe; Matthew B Dobbs; Christina A Gurnett Journal: J Med Genet Date: 2020-06-09 Impact factor: 6.318