When an injury necessitates the use of a cast for immobilization, one of the associated challenges is the potential for muscle atrophy due to lack of movement and reduced activity. Muscle atrophy, characterized by the wasting away of muscle tissue, can significantly impact the strength and function of the affected limb. There are a certain number of strategies that patients can adopt to reduce muscle atrophy while wearing a cast, promoting optimal recovery, and minimizing the impact on overall muscle health.
Electrical muscle stimulation involves the application of electrical impulses to stimulate muscle contractions. This technique can be used as an adjunct to conventional rehabilitation to prevent muscle atrophy. By inducing muscle contractions without joint movement, electrical muscle stimulation helps preserve muscle mass and strength during periods of immobilization 1. In particular, brief periods of low-voltage percutaneous electrical stimulation have been shown to reduce quadriceps atrophy secondary to knee immobilisation. This may help by preventing the decrease in muscle protein synthesis that usually occurs following limb immobilization 2.
Acupuncture is a common and frequently used therapy in complementary and alternative medicine which exerts its therapeutic effects through the insertion of a needle at a specific acupuncture point, altering the energy and blood circulation. Acupuncture has traditionally been used as a therapeutic intervention to control pain but has also been proven to reduce skeletal muscle atrophy induced by 14 days of cast-immobilization 1.
The electro-acupuncture intervention leverages the same needling strategy as an acupuncture treatment but delivers an electrical current as well. Data has demonstrated that an electro-acupuncture treatment performed three times per week during a 14-day immobilization period for a duration of 15 min can also significantly reduce skeletal muscle atrophy associated with cast-immobilization 1.
While traditional resistance exercises may not be feasible with a cast, isometric exercises can be performed to activate muscles without moving the joint. Isometric contractions involve tensing the muscles without changing the length of the muscle or the angle of the adjacent joint. These exercises help maintain muscle strength and prevent excessive muscle loss. According to new research published in 2021, training the opposite, non-immobilized limb while one recovers could help maintain muscle mass for both 3.
Maintaining proper hydration is crucial for overall health, including muscle health 4. Relatedly, proper nutrition plays a critical role in mitigating muscle atrophy while wearing a cast. Adequate protein intake is particularly essential, as proteins are the building blocks of muscle tissue. Supplementing with amino acids, the components of proteins, may support muscle preservation. Additionally, maintaining overall nutritional health, including sufficient calorie intake and vitamins, is vital 5.
Frequent monitoring of muscle condition and joint mobility is essential during cast immobilization. In addition to visual inspection, this can be informed by magnetic resonance imaging (MRI) scans over the course of rehabilitation to assess muscle strength among other factors 6,7. Any signs of muscle wasting or joint stiffness should be promptly addressed through adjustments in the rehabilitation plan. This may include modifying exercises, changing the cast for better access, or reassessing the overall rehabilitation strategy.
References
1. Brock Symons, T. et al. Attenuation of skeletal muscle atrophy via acupuncture, electro-acupuncture, and electrical stimulation. Integr. Med. Res. (2023). doi:10.1016/j.imr.2023.100949
2. Gibson, J. N. A., Smith, K. & Rennie, M. J. PREVENTION OF DISUSE MUSCLE ATROPHY BY MEANS OF ELECTRICAL STIMULATION: MAINTENANCE OF PROTEIN SYNTHESIS. Lancet (1988). doi:10.1016/S0140-6736(88)92417-8
3. Valdes, O. et al. Contralateral effects of eccentric resistance training on immobilized arm. Scand. J. Med. Sci. Sport. 31, 76–90 (2021). doi: 10.1111/sms.13821.
4. Lorenzo, I., Serra-Prat, M. & Carlos Yébenes, J. The role of water homeostasis in muscle function and frailty: A review. Nutrients (2019). doi:10.3390/nu11081857
5. Wang, Y. et al. Nutraceuticals in the prevention and treatment of the muscle atrophy. Nutrients (2021). doi:10.3390/nu13061914
6. Psatha, M. et al. A longitudinal study of muscle rehabilitation in the lower leg after cast removal using magnetic resonance imaging and strength assessment. Int. Biomech. (2015). doi:10.1080/23335432.2015.1070686
7. Yamauchi, K. et al. Muscle atrophy and recovery of individual thigh muscles as measured by magnetic resonance imaging scan during treatment with cast for ankle or foot fracture. J. Orthop. Surg. (2017). doi:10.1177/2309499017739765