Ankle Sprains: Lost In Translation

ankle-anatomy-jmmHe limped off the field, and tried to convince manager Rick Renteria to let him keep playing. Instead, Castro had an MRI and X-rays, which showed no fracture or ligament damage.

Something is getting lost in the translation from what the Cubs doctors told the baseball staff. Although I don’t have a direct quote from the Cubs medical staff, what gets lost in translation is simple to repair.
An ankle sprain is ligament damage. That’s what ankle sprains are. Starlin Castro has a grade 2 high ankle sprain. I’ll translate that in what follows.

Presenting the TCR, “ABC’s” to ankle sprains, after the jump…

Demonstrated below is an animation describing the ankle anatomy and terminology (about 6 minutes). It includes key terms such as the ankle mortise and the difference between ligaments and tendons and all the ankle ligament anatomy.

First, all ligament injuries (even outside the ankle) are graded 1-3. This is true for all joints including the shoulder (AC joint) and the knee (ACL, MCL, etc).

Type 1 is a sprain/ligament injury where the fibers of the ligament are injured but not stretched.  Type 2 sprains are when the collagen fibers of the ligament are injured and stretched but not completely torn apart. Regarding the ankle, these rarely need surgery and heal with conservative measures such as bracing and therapy but take a bit longer to resolve, usually 4-8 weeks. Finally, type 3 sprains represent a complete disruption or tear of the ligament. Jed Hoyer, when reporting to the media on Castro’s ankle injury said that there was “no torn ligaments” (implying it wasn’t a grade 3 injury). The media then reported no ligament injury. Voilà, Lost in Translation.

What Starlin Castro has, isn’t the most common or typical ankle sprain. Watching the video of his slide at home plate, his spike got caught under him and forced the ankle downward. Most common lateral ankle sprains roll the hindfoot under the ankle. A high ankle sprain involves ligaments that connect the fibula (lateral malleolus or outside ankle bone) to the tibia (larger ankle bone). The ligaments are significant and are both in front of (anterior tibiofibular ligament) and behind (posterior tibiofibular ligament) both bones. There is a membrane (interosseous membrane) that also connects the two bones and runs the entire length of the leg. High ankle sprains can take a bit longer to recover compared to lateral sprains, in the range of 6-12 weeks and that will depend on the grade of injury. Castro’s was described as grade 2. Grade 3 sprains are more significant as ligaments are completely disrupted and if the space between fibula and tibia is widened, could require surgery to tighten the ligaments as they heal.

Conventional, roll your ankle, lateral sprains involve the ligaments from the distal fibula on the outside of the ankle (again, lateral malleolus or lateral ankle bone and distal means lower on the fibula) to the hindfoot bones: the calcaneus/heel bone and the talus, which is the bone that makes up the bottom of the ankle joint.  The most commonly injured of these is the anterior talofibular ligament. The calcaneofibular and posterior talofibular ligaments are often injured in more severe lateral sprains. Most non-athletes get non-surgical treatment even in grade 3 sprains but there are situations where recurrent sprains occur because the ligaments healed with significant laxity. In this situation, there are many operative procedures designed to tighten up the ligament complex. The most popular of these procedures currently is named the Brostrom procedure. I’ll keep the videos schematic but there are live videos of the procedure available for those who are interested.

The medial (inside) ankle ligament is called the deltoid. It can also be sprained and similar options for treatment are available. This ligament is more oftened injured in conjunction with a fibular fracture. If it is a grade 3 ligament injury, the ankle joint (mortise, hinge) is widened and is treated by surgically fixing the fibular fracture. Sometimes, if the ligament gets trapped in the joint, it can block the ability to restore the joint space to normal. In this situation, opening and repairing that ligament will restore the ankle mortise.  Once the widening of the ankle joint alignment is restored, the deltoid ligament will heal at an appropriate length. The above described ankle ligaments are all extra-articular, meaning outside the joint. There is excellent blood supply to let these ankle ligaments heal in comparison to the knee’s anterior cruciate ligament (ACL) which runs inside the knee (intra-articular) and when torn (grade 3) will not heal with normal function because it crosses the joint through joint fluid where the blood supply to the ligament is limited.

Anatomy of the Ankle