Understanding Marcus Smart’s Tibiofibular Subluxation

• Post By: Jeff Stotts
• Date: November 23, 2015
• Category: NBA, Understanding...

NBA injury reports can be maddening. Some teams elect to carefully guard their injury information and provide the public with vague descriptions that often involve non-specific regions of the body. Others are more transparent and provide details that accurately and vividly describe an injury. Fortunately the Celtics were the latter regarding Marcus Smart’s leg injury, revealing the second year guard recently suffered a subluxation of the proximal tibiofibular (tib-fib) joint.

The description of the injury provides details regarding the extent of the damage and precisely where it occurred. The term subluxation means the involved joint temporarily shifted from its normal alignment. A subluxation is often described as a partial dislocation. The dislocation is considered incomplete, meaning the neighboring ligaments and musculature often force the joint back into alignment and medical assistant to re-align the area is not usually warranted. However the shift can result in damage to the involved soft tissue structures like muscles of ligaments. It appears any associated damage in Smart’s case is minimal, as surgery will not be needed.

The specific joint Smart injured is the tibiofibular joint, an articulation formed by the two lower leg bones, the tibia and fibula. The inclusion of the word proximal indicates the injury occurred at the area closest to the knee where a bony rim of the tibia touches the round head of the fibula. The area is fortified with multiple ligaments to insure stability.

Fortunately for Smart the proximal tib-fib joint is not a major weight-bearing joint. Instead its primary responsibilities include the dispersion of forces applied to the ankle, particularly with a pulling or tensile load. It also helps absorb forces applied to the outside portion of the leg, which could explain how the injury occurred following Smart’s collision with Brooklyn’s Thomas Robinson.

Moving forward Ed Lacerte and the Celtics medical staff will first focus on controlling the associated symptoms like pain and swelling. They will then shift their attention to insuring any sprained ligaments appropriately heal. Doing so will prevent any chronic instability from developing and help prevent a shift in Smart’s overall biomechanics. This is particularly important given his history of lower leg injuries. Fortunately the blood supply to the area is strong, and barring a complication with the nearby peroneal nerve, a complete recovery is very possible.

However the necessary time needed to rest and rehab remains in flux. The initial timeline provided by Boston suggests Smart will miss at least two weeks, though that would easily be a best-case scenario. Unfortunately the rarity of the injury makes it hard to find a comparison and a four-to-six week recovery is a safer estimate.

The Celtics currently sit a half game out of the Eastern Conference playoff picture and play six of their next eight away from TD Garden, including a five game road trip. Their return to Boston will be anything but easy with home games against the Bulls and Warriors scheduled. In the meantime, Avery Bradley and Isaiah Thomas will be leaned on heavily with Evan Turner expected to see an increase in responsibilities. Still Smart’s absence will be felt on the defensive end and determining how to minimize that impact could go a long way to shaping Boston’s long-term success.