Hip dysplasia is more severe in Charcot-Marie-Tooth disease than in developmental dysplasia of the hip.
BACKGROUND
Patients with Charcot-Marie-Tooth disease may develop hip dysplasia. Hip geometry in these patients has not been well described in the literature.


OBJECTIVE
We compared the hip morphometry in Charcot-Marie-Tooth hip dysplasia (CMTHD) and developmental dysplasia of the hip (DDH) in terms of extent of (1) acetabular dysplasia and subluxation, (2) acetabular anteversion and osseous support, (3) coxa valga and femoral version, and (4) osteoarthritis.


METHODS
Fourteen patients with CMTHD (19 hips; mean age, 23 years) presenting for periacetabular osteotomy were matched to 45 patients with DDH (45 hips; mean age, 21 years) based on age, sex, and BMI. We assessed acetabular dysplasia and subluxation using lateral center-edge angle (LCEA), anterior center-edge angle (ACEA), and acetabular roof angle of Tönnis (TA) on plain pelvic radiographs and acetabular volume, area of femoral head covered by acetabulum, and percentage of femoral head covered by acetabulum on three-dimensional CT reconstruction models. Acetabular version and bony support, femoral version, and neck-shaft angle were measured on two-dimensional axial CT scans. Hip osteoarthritis was graded radiographically according to Tönnis criteria.


RESULTS
Acetabular dysplasia was more severe in CMTHD, as measured by smaller LCEA (p < 0.001), ACEA (p < 0.001), and acetabular volume (p = 0.0178) and larger TA (p = 0.025). Hip subluxation was more pronounced in CMTHD, as demonstrated by lower area of femoral head covered by acetabulum (p = 0.034) and percentage of femoral head covered by acetabulum (p = 0.007). CMTHD was associated with higher acetabular anteversion (p < 0.001), lower anterior (p < 0.001) and posterior (p = 0.072) osseous support, and more severe coxa valga (p < 0.001). More (p = 0.006) arthritic hips were found in CMTHD.


CONCLUSIONS
The extent of acetabular dysplasia, hip subluxation, acetabular anteversion, coxa valga, and hip osteoarthritis was more severe in CMTHD. These findings are important in choosing the appropriate surgical strategy for patients affected by CMTHD.
Department of Orthopedic Surgery, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO, USA.
Eduardo N
EN
Novais
Sara D
SD
Bixby
John
J
Rennick
Patrick M
PM
Carry
Young-Jo
YJ
Kim
Michael B
MB
Millis
D000077:Acetabulum / Q000002:abnormalities / Q000000981:diagnostic imaging* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D002607:Charcot-Marie-Tooth Disease / Q000150:complications*; D016009:Chi-Square Distribution; D060906:Coxa Valga / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D005269:Femur / Q000002:abnormalities / Q000000981:diagnostic imaging* / Q000601:surgery; D020342:Finite Element Analysis; D006617:Hip Dislocation / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D006618:Hip Dislocation, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000209:etiology; D016014:Linear Models; D008297:Male; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000209:etiology; D010027:Osteotomy; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D055815:Young Adult