A Histological Study on the Effect of Dextrose Prolotherapy on Skeletal Muscle Injury in Adult Male Albino Rats

Abstract Background Skeletal muscle injuries are one of the most common injuries occurring in sport medicine varies from 10% to 55% of all injuries. Phases of muscle injuries includes a series of complex stages including inflammation, regeneration and remodeling. Treatment of the injuries is based on conservative measures as rest, elevation, physical therapy and non steroidal anti-inflammatory medications. Many injection protocols have been proposed for the treatment of muscle lesions as corticosteroid injection. Recently prolotherapy appears to have a safety profile comparable with other injection procedures. Aim of the work The aim of the present work is to determine the efficacy of dextrose prolotherapy in treatment of skeletal muscle injury in adult male albino rats. Material and methods Sixty six adult male albino rats were used in the study. They were divided into control (group I) and experimental groups. Control group: rats were left without any intervention. The experimental group was group II that was divided into sham operated group in which skin incision was done in the left hindlimb without injury to gastrocnemius (group II`) and muscle injury group in which transverse cut injury across the midbelly of the gastrocnemius muscle of right hindlimb was done (group II``) and group III that was divided into lidocaine injected group in which skin incision in lefthindlimb was done without injury to gastrocnemius followed by injection of 0.3 ml 1% lidocaine was injected across the muscle (group III`) and muscle injury treated with dextrose prolotherapy group in which a transverse cut injury across the midbelly of gastrocnemius of right hindlimb was done followed by injection of 0.1 ml of dextrose prolotherapy of mixture of 0.1ml of 12.5% dextrose and 0.3 ml of 1% lidocaine (group III``). The animals were received 6 injections of lidocaine and dextrose prolotherapy at 5 days interval (starting from day 0 to day 25). In group II and III, muscle specimens were taken at 5,12 and 28 days and processed for light microscope Results Examination of Group II``A (5 days untreated group) showed intense infiltration of mononucleated inflammatory cells intermingling with dispersed myoblasts and macrophages. Group II`` B (12 days untreated group) showed regenerating myotubes intermingling with mononuclear inflammatory infiltrate and macrophages. Group II``C (28 days untreated group) showed some muscle fibers with peripherally elongated nuclei while others showed centrally vesicular ones. Examination of group III``A (5 day treated group with prolotherapy) showed longitudinal regenerating myofibers with multiple rows of internal vesiculated nuclei. Group III``B (12 days treated group) showed newly formed myofibers with incomplete striations together with well developed newly formed striated longitudinal muscle bundles with peripheral flattened nuclei, group III``C (28 days treated group) showed cross striated muscle fibers with the appearance of elongated vesicular nuclei. Conclusions dextrose prolotherapy was effective in soft tissue healing as it accelerated myoblast proliferation and differentiation