Syndesmosis Injury from Diagnosis to Repair: Physical Examination, Diagnosis, and Arthroscopic-assisted Reduction

SLR - November 2020 - Scott J. Hudzinski

Reference: Wake, Jeffrey DO; Martin, Kevin D. DO, FAAOS Syndesmosis Injury from Diagnosis to Repair: Physical Examination, Diagnosis, and Arthroscopic-assisted Reduction, Journal of the American Academy of Orthopaedic Surgeons: July 1, 2020 - Volume 28 - Issue 13 - p 517-527 doi: 10.5435/JAAOS-D-19-00358

Scientific Literature Review

Reviewed By: Scott J. Hudzinski, DPM
Residency Program: Crozer Chester Medical Center – Upland, PA

Podiatric Relevance: The foot and ankle surgeon who has a primarily active and athletic population is going to see his/her fair share of acute and chronic lateral ankle pain secondary to syndesmotic instability. The condition is often overlooked during a problem focused examination However, the growing knowledge of syndesmosis injuries has come with an increase in incidence reported with ranges from 17 percent to 74 percent. Syndesmotic injuries are often highly debilitating injuries in which athletes have trouble performing sudden moves which can result in lingering chronic pain. This literature review is covering isolated syndesmotic injuries to help establish a diagnosis and treatment protocol.

Physical Exam: Physical exam findings are positive tenderness to palpation anterolaterally at the level of the ankle joint, pain on cross leg test, fibular translation test, and dorsiflexion external rotation stress test. A dynamic test is composed of having the patient walk 10 feet, then walk on heels then tiptoes, followed by standing-double and single leg heel raises and pivot test. Taping circumferentially above the ankle to stabilize the syndesmosis for repeat of dynamic test. No single test is sufficiently accurate for diagnosis.

Radiographic exam: Radiographic findings that have been identified as syndesmosis injury indicators are increased tibiofibular clear space, decreased tibiofibular overlap, and increased medial clear space. On MRI, Fluid making a T2 signal from the mortise up through the syndesmosis is termed the “Lambda sign”.

Exam under Anesthesia: EUA is done to include dorsiflexion, dorsiflexion external rotation stress, fibular translation test, medial/lateral talar tilt, and an anterior drawer. A complete diagnostic arthroscopic examination is done to include evaluating for distal tibiofibular stability, OCDs, and deep deltoid. Arthroscopic stability testing includes repeating all the previous listed maneuvers while directly visualizing anatomic structures. Cotton test with a 4.0 millimeter shaver can be used to evaluate as well.

Surgical Management: Isolated syndesmotic injury can be reduced using a two point bone clamp. Fixation can be trans-syndesmotic screws(3.5/4.0 millimeter), suture button, or suture button with AITFK augmentation. Suture button fixation are favorable, with multiple meta-analyses demonstrating higher AOFAS scores and lower rates of postoperative complications, even earlier time to full weight-bearing when compared with syndesmotic screws with no need for hardware removal or concerns for broken hardware. Using two suture buttons does not appear to contribute to further stability. A cadaveric study was done showing screw fixation to be too rigid, suture buttons unstable, but combination of suture buttons with AITFL augmentation with suture tape appears to be as dynamic as intact syndesmosis complexes. Post-op course is non weight-bearing splint for 10 to 14 days. Transition to CAM boot at two weeks with ROM exercises and physical therapy. Lace-up ankle brace at four weeks. Return to sport if they can do a single leg hop and heel raise at six weeks.