Issue link: https://www.massageandbodyworkdigital.com/i/1501042
L i s te n to T h e A B M P Po d c a s t a t a b m p.co m /p o d c a s t s o r w h e reve r yo u a cce s s yo u r favo r i te p o d c a s t s 77 TAKEAWAY: Many references (including those online) are updating their facts to correctly identify retinacula as a thickening of the fascia of the leg. The group used dissection, histological and immunohistochemical analysis, and MRIs to examine seven healthy ankles and 17 with sprains in their history. Overall, the area known as the retinaculum was easily identifiable in all subjects due to the aforementioned thickening. The retinaculum has three layers of collagen fibers that alternate in orientation and are separated by a thin layer of loose connective tissue. This is in keeping with the overall histology of the entire crural fascia, but a crucial difference is that in the area of the retinaculum, the collagen is thicker and the loose connective tissue thinner. It's so thin it was concluded that any effect on tendon stability would be minimal at best, and too weak to function like a pulley. 1 From a topographical anatomy standpoint, it may be more useful to imagine retinacula as forming a series of porticos, or a corrugated roof, that houses the tendons, allowing them to slide underneath without bowing, slackening, or becoming entangled with their neighbors. Even more interesting is that retinacula were not truly separable from the entire crural fascia and the deep fascia of the foot and lower leg. With such profound connections to their associated epimysium of the muscles of the lower leg, including the deep posterior compartment, a reassessment was in order. Remember, the majority of free nerve endings that transmit proprioceptive information are found in both the superficial fascia and the muscle-wrapping layer of the epimysium. This suggests a strong theory that the primary function of retinacula is to transmit proprioceptive information from the ankle to the knee, the hip, and the rest of the body with every step you take. MOBILIZE Armed with this knowledge, let's go back to our elderly person with the walker and perform a pathological hot take. Trust me, it's a logical one. Combining our new understanding of the function of retinacula with our knowledge that the purpose of hyaluronan in the epimysial layers is to keep things sliding and the free nerve endings happy (see "Hyaluronan Makes the Body Glide," Massage & Bodywork May/June 2023, page 76), it is easy to hypothesize that any long- term use of a walker (3 months or more) is going to create densifications within the fascia ankle and other aspects of the foot and lower leg because the person using the walker is going to be shuff ling their feet. This decreases the stimulating shearing motions necessary for the fasciacytes to keep the hyaluronan smooth and slick. It also disrupts the feedback loop from the ankle to the rest of the body. Now, I'm not saying we should do away with walkers. Rehab devices have their purpose as long as we don't get too dependent on them. That obviously creates a feedback loop that only serves to further decrease proprioception and encourage further dependence. What is vital is to do manual interventions that increase ankle mobility in all ranges of motion. And be sure the person we're treating understands the importance of this for their recovery. I also encourage them to do regular, functional proprioceptive exercises daily. Simple things, like slowly pedaling the feet before getting out of bed or a chair, can reap excellent long-term benefits. As their confidence improves, I show them how to work with yoga straps to provide resistance as well as safe, self-assisted stretching for the whole leg to encourage improved proprioceptive relationships throughout the crural fascia. There is also taping, which in this instance is thought to promote proper collagen reformation. Of course, these strategies will work well with anyone recovering from an ankle injury. As always, work within individual limitations and resist the urge to do too much too fast. Daily mindful efforts can have them putting their best foot forward in no time. Note 1. Carla Stecco et al., "The Ankle Retinacula: Morphological Evidence of the Proprioceptive Role of the Fascial System," Cells Tissues Organs 192, no. 3 (2010): 200–210, https://karger.com/cto/ article-abstract/192/3/200/90946/The-Ankle- Retinacula-Morphological-Evidence-of-the. David Lesondak is an allied health member in the Department of Family and Community Medicine at the University of Pittsburgh Medical Center, and is board- certified in structural integration. He is the author of Fascia: What It Is and Why It Matters, editor of Fascia, Function, and Medical Applications, and host of the podcast BodyTalk. Learn more at davidlesondak.com.