Effects of Longidase® on skeletal muscles in children with cerebral palsy

Rehabilitation of children with spastic cerebral palsy (CP) is highly relevant considering the impaired movement, support and posture in these patients with spasticity of various muscles. Spasticity in CP patients may lead to severe secondary bone changes, such as hip dislocation, severe foot deformities (equinovarus or planovalgus), scoliosis, severe multiple contractures of the upper limb joints. Despite being a good agent to relieve spasticity, botulinum toxin is not able to completely address the problems associated with deformities and movement disorders due to muscle rigidity and changes in muscle structure.Reducing muscle rigidity using Longidase® (hyaluronidase azoximer) is an important stage of rehabilitation of CP children. Longidase® has a prolonged enzymatic activity and contributes to a pronounced antioxidant and anti-inflammatory effect. Longidase® also has antifibrotic properties since it mitigates inflammation and regulates the production of inflammatory mediators. Longidase® is capable of depolymerizing connective tissue matrix in fibrous granulomatous formations. Moreover, it suppresses the negative feedback reaction aimed at the production of connective tissue components, which is very important in case of muscle spasticity in both children and adult patients. Longidase® reduces tissue edema, thereby increasing the range of motion in joints, reducing contractures, and preventing their formation. The development of step-by-step rehabilitation, which includes botulinum toxin therapy at the first stage and Longidase® injections into spastic muscles at the second stage, will increase muscle elasticity and range of motion and facilitate orthosis in childhood, thus postponing surgery.We report a case of CP in a 7-year-old girl who was treated in Saint Petersburg State Pediatric Medical University. The patient had regular courses of botulinum toxin A therapy to reduce muscle spasticity and prevent persistent contractures. In addition to that, the patient received a course of ultrasound-guided Longidase® injections into spastic lower limb muscles a week following botulinum toxin therapy. Muscle echogenicity was assessed using ultrasound examination. Spasticity in the upper and lower extremities was detected in more than one joint. Patient’s score on the Modified Ashworth Scale was 3 for the lower limb. Longidase® injections significantly increased the range of motion in the ankle joint and ensured smooth sliding of muscle groups during physical exercises. Longidase® therapy was considered because of the need for surgery, while parents wanted to try alternative treatment strategies to postpone surgery.Thus, botulinum toxin therapy followed by intramuscular Longidase® injections reduced rigidity of spastic muscles and increased the amplitude of passive and active movements in the ankle joint, as demonstrated by goniometry and ultrasound, as well as changes in the perimysium and endomysium.