Rotational and angular deformities of the lower extremities are among the most common orthopedic complaints to primary care providers. Fortunately, most patients have nothing more than normal physiologic variance, and the majority may be treated with education and observation. However, there are a variety of uncommon, but significant, orthopedic and neuromuscular conditions that may present as rotational or angular deformity. Thus, an understanding of both anatomy and potential pathologies is important. Recognition of normal variations in normal growth and development can reduce the number of unnecessary referrals for specialist evaluation.
Although the vast majority of parental concerns regarding rotational difference will represent nothing more than developmental norms, it is paramount to remember that rotational differences may be the presenting complaint in patients with mild neuromuscular differences; thus, a careful history and physical exam focusing on neuromuscular development should be incorporated with every patient who presents for evaluation of in- or out-toeing.
In-toeing is perhaps the most common gait deviation that presents for medical assessment. Assessment should begin with observation of the gait to determine the foot progression angle, namely the angle described by the intersection of the axis of the foot with the axis of progression. Although the torsional alignment of the lower extremities changes during skeletal development, most parents are unaware of this fact and will consider any deviation from the normal adult value of 10 to 20 degrees external as pathologic (Fig. 209-1). If an internal foot progression angle is identified, careful examination of the lower extremities can identify the anatomic location responsible for the inward deviation. Fortunately, because of normal physiologic variance, usually a strong correlation exists between the age of the patient and the anatomic location producing the inward deviation.
The normal evolution of hip rotation, knee angle (ie, mechanical axis), tibial torsion, angle of gait (ie, foot progression angle), and arch development in children between 0 and 14 years of age. (Reproduced with permission from Engel, G.M. and L.T. Staheli, The natural history of torsion and other factors influencing gait in childhood. A study of the angle of gait, tibial torsion, knee angle, hip rotation, and development of the arch in normal children, Clin Orthop Relat Res 1974; Mar-Apr;(99):12-17.)
Metatarsus adductus is the most frequent reason for in-toeing in the first year of life and is the most common congenital foot deformity, affecting approximately 3% of all births. Metatarsus adductus occurs when there is inward torsion of the mid- or forefoot with the hindfoot in normal position or slight valgus. It is bilateral in 60% of children. It is important to distinguish metatarsus adductus from more significant foot pathology—namely, talipes equinovarus (clubfoot). This distinction may be accomplished by assessing the ...