Orthopedics - Oleksa A.P. 2006

Pathophysiology of Joints
Developmental Defects and Congenital Skeletal Anomalies
Larsen Syndrome

Larsen and co-authors (Larsen L.J., Schottstaedt E.R., Bost F.C., 1950) described 6 cases in children presenting with multiple congenital dislocations of various joints, typical craniofacial dysmorphism, a flat face, prominent forehead, depressed nasal bridge, and hypertelorism. Dislocations or subluxations of the elbow and knee joints may occur. FOOT deformities such as Clubfoot (equinovalgus or equinovarus) are characteristic of this syndrome. Abnormal spinal segmentation, cylindrical fingers, delayed appearance of ossification centers in the hand bones, and a high-arched palate are also observed in affected children (Larsen L.J. et al., 1950; Steel H.N., Kohl E.J., 1972). As noted by the same authors, the calcaneus may exhibit two ossification centers that eventually fuse as the child grows. Larsen syndrome is inherited in an autosomal dominant manner (Latta R.J., Graham C.V., Aase J. et al., 1971).

Treatment involves orthopedic reduction of joint dislocations or subluxations and foot deformities. First, the deformity of the knee joints is corrected, followed by the hip joints.

Subluxations and dislocations of the knees are managed through serial manipulations (repositioning) with gradual flexion, though surgical intervention is occasionally required. Fibrous bands within the vastus medialis and vastus lateralis Muscles, as well as the fascia lata, cause knee contracture and deformity. A hallmark feature is chronic knee instability.

Dislocation or subluxation of the Femur is likewise treated conservatively or, in some cases, surgically. Subluxation of the radial HEAD is difficult to resolve conservatively, making surgical resection (removal of the head) more common.

Foot deformities are managed conservatively via corrective manipulations followed by the application of plaster casts, though supplementary surgical correction is sometimes necessary. Most of these children subsequently require orthopedic footwear, and occasionally prosthetic support.