Management of Multiple Joint Dislocation in a Child with Larsen's Syndrome: A Case Study

Sandra Smith, MSPT; Dawnne Karsky, PA; Harry Kim, MD; Shriners Hospital, Tampa, FL


Children with Larsen's syndrome can exhibit multiple congenital skeletal abnormalities with both similarities and variations in presentation. Larsen's syndrome was initially described in 1950 by Larsen et al (1), who reported on six children with dwarfism, a similar facies with prominent forehead, wide spaced eyes, low or flattened nasal bridge, as well as shortened metacarpal and long cylindrical fingers. Other associated findings included cleft palate, hearing deficits, upper extremity dislocations primarily in the elbows, and abnormalities in the cervical and thoracic vertebrae. The most challenging deformities for the orthopedic team are the dislocations affecting the hips and knees. Equinovalgus deformities of the feet are also very common in these children. Knee dislocations can be the most striking deformity the severity of involvement can vary from laxity causing knee recurvatum (Grade I) to complete dislocation of the tibiae posteriorly (Grade III). Larsen initially believed that these cases were not inherited. However, later reports of Larsen's syndrome in a family of three generations indicated that the syndrome was probably autosomal dominant or recessive but could also be due to a parental germ-line mosaicism (2).

In 1994, Laville et al (3) described 38 cases of Larsen's syndrome in families living on a remote island off the eastern coast of Africa in the Indian Ocean. These patients were followed for an average of 13 years. Thirteen deaths in these children by age two was secondary to cervical spine dislocation, tracheomalacia, heart disease and severe respiratory infection. Long-term challenges for these children as they grow include progressive scoliosis, recurrent knee dislocations, and arthritis.

All articles reviewed on Larsen's syndrome (1-5) shows consensus for early orthopaedic treatment with a combination of conservative and operative procedures for the feet and knees. Unilateral hip dislocations should be treated by age 2 by open reductions while bilateral dislocation can be left alone and monitored as they are many times stable and asymptomatic.

This case study relates the treatment provided to a female child from Peru after admission to the Tampa Shriners Hospital for Children with a preliminary diagnosis of arthrogryposis. Lisa was 18 months old and was accompanied by her mother. She received evaluations by the orthopedic surgical staff, pediatrician and therapy disciplines. Through clinical, radiographic, and functional exams Lisa was correctly diagnosed with Larsen's syndrome. She had the typical facies and a dislocated radial head in the right upper extremity. Besides a cleft palate, she also had a right hip dislocation (Figure 1 ), and both knees had Grade III posterior dislocations (Figures 2,3 ). Her C-spine radiograph was negative but she also had severe equinovalgus deformity secondary to vertical tali.

Figure 1

Figure 2, 3

 

Functionally, she showed obvious gross motor delay secondary to her poor lower extremity alignment. Lisa's bilateral ankle deformities were fixed, while both hips were hyper mobile. Knee range of motion measured 25 degrees of hyperextension with 90 degrees of flexion on the right, and the left knee hyper extended to 45 degrees with 20 degrees of flexion. Although she could pull to stand, Lisa 's main method of self-mobility was scooting on her bottom or bear crawling.

The Speech pathologist suspected a hearing deficit, which was verified by audiol-ogy testing. In addition, she had a speech delay and cleft palate. During eating she had consistent nasal regurgitation and her mother reported a history of multiple ear infections and several episodes of upper respiratory illnesses. The Occupational therapy evaluation showed a mild right elbow contracture, which did not interfere with age appropriate fine motor skills or activities of daily living. The therapist did not recommend any upper extremity splinting.

Lisa's surgeries and rehabilitative care was performed over seven months during her hospital stay. The surgical plan began distally, with a staged vertical tali repair starting on the left and concomitant, serial long leg casting to non-operatively manage her knee dislocations. While Lisa's left knee responded to an aggressive casting regimen and the right knee continued to show hyperexten-sion that prompted a quadricepsplasty. At the same time, her right hip was examined under anesthesia and a closed reduction with an adductor tenotomy was performed. Hip spica immobilization also provided additional casting to her knees. Lisa's final surgery was an extension tibial osteotomy with petrie cast immobilization to gain the desired stability and range of motion in her right knee.

Meanwhile, her ENT evaluation showed a moderate reduction conductivity hearing loss bilaterally. Lisa's cleft palate was repaired and three months later she had myringotomies to decrease the risk of future ear infections. By the time she was discharged from the hospital, Lisa received hearing aids and showed significant improvement in age appropriate receptive and expressive language skills in both Spanish and English.

Once all her orthopedic surgeries were completed and casting discontinued, Lisa was ready to begin orthotic and physical therapy treatment. Initially, HKAFO's set in hip abduction with 25 degrees of knee flexion was necessary to control her hip and knee position and ensure that the correction obtained surgically was maintained (Figure 4 ). She had free hip flexion and the knee remained locked in standing. Secondary to a solid ankle AFO component, her shoes required wedging at the heels to maintain balance within her center of gravity. At night her hip position was at 90 degrees of hip abduction with an Ilfeld brace and she wore AFO's.

Figure 4

Lisa progressed rapidly from a standing program to meet her discharge goal of ambulating full time with a reverse four-wheeled walker and using a stroller for long distance community mobility. After discharge Lisa's mother relocated locally to allow follow up through frequent outpatient clinic visits. She was able to tolerate free knee motion with extension blocks on the left followed by the right and the pelvic band was removed. This allowed her to begin strengthening of her hip musculature while walking and exercising in her KAFO's.

Lisa, now three years old, ambulates independently without an assistive device in KAFO's and rides a tricycle. She continues to have a 5-degree right knee flexion contracture with mild valgus deformity in the full available extension range. As expected, Lisa requires frequent and close monitoring of her residual deformities as she grows including her right hip subluxation. However, due to early surgical management and consistent follow through with the team's recommendations for therapy and orthoses wear, Lisa's future looks hopeful for minimal orthopedic impairment and age appropriate function.

References:

 

    1. Larsen LJ, Schottstaedt ER, Bost FC. Multiple congenital dislocations associated with characteristic facial abnormalities. J Pediatr 1950;37:574-81.

 

    1. Petrella R, Rabinowitz JG, Steinmann B, Hirschhorn

 

    1. K. Long-term follow-up of two sibs with Larsen Syndrome possibly de to parental germ-line mosaicism. Am J Med Genet 1993;47:187-197.

 

    1. Laville JM, Lakermance P, Limouzy F. Larsen's syndrome: Review of the literature and analysis of thirty-eight cases. J Pediatr 1994;14:63-73.

 

    1. Samuel AW, Davies DRA. The Larsen syndrome with multiple congenital dislocations and a normal facies. Int Orthop 1981;5:229-232.

 

  1. Munk S. Early operation of the dislocated knee in Larsen's syndrome. Acta Orthop Scand 1988;59:582-584.