Freeman-Sheldon Syndrome with Stiff Knee Gait - A Case Report.

Introduction: Freeman-Sheldon syndrome (FSS), also known as the distal arthrogryposis (DA) type 2A, is a rare congenital anomaly. We report a unique case of the DA type 2A with mixed clinical features and the unusual presentation of bilateral congenital dislocation of the knee but had unassisted stiff knee gait.

Case Report: A 5-year-old female child presented to the clinic with the complaint of inability to bend both knees since birth. She had an unassisted bipedal gait, but could not squat, cross-leg sit, run, and climb stairs without assistance. Her youngest brother had a similar presentation but succumbed to death at the age of 5 months due to respiratory distress. Clinical features were in the favor of FSS. Her serum creatinine kinase level was normal and the electromyography of bilateral tibialis anterior and abductor pollicis brevis was not suggestive of the myotonia. Radiograph of the skull showed cooper beaten skull appearance whereas bilateral pelvis with the hip showed following changes in the right hip; decrease femoral epiphysis height, horizontal proximal femoral physis, and the coxa brevia. She was initially managed conservatively by weekly stretching, manipulation, and casting. As a result, she could flex her knee up to 20°. Although the quadricepsplasty might be helpful for the persistent extension deformity, there was marked quadriceps weakness which could make it harder for the child to stand and walk. In addition, the abnormal muscle physiology in FSS may result in unfavorable outcomes after the surgery. Moreover, a consideration of the surgical aspect is not free of risks which include difficult endotracheal intubation, vein access, and malignant hyperthermia.

Conclusion: FSS is a rare congenital anomaly that should be differentiated from another syndrome of the close resemblance, Sheldon Hall syndrome and Schwartz Jampel syndrome which are other rare autosomal recessive disorders characterized by myotonia and the chondrodysplasia. Conservative management has still a role in bilateral knee involvement especially if the patient is an independent walker.