Introduction Also known as a "high ankle sprain" Epidemiology incidence 0.5% of all ankle sprains without fracture 13% of all ankle fractures Pathophysiology mechanism of injury most commonly associated with external rotation injuries pathoanatomy external rotation forces the talus to rotate laterally and push the fibula away from tibia may lead to increased compressive stresses seen by the tibia increased likelihood of lateral subluxation of the distal fibula incongruence of the ankle joint articulation Associated injuries osteochondral defects (15% to 25%) peroneal tendon injuries (up to 25%) fractures ankle Weber C Weber B other 5th metatarsal base anterior process of calcaneus lateral or posterior process of talus deltoid ligament injury loose bodies Prognosis missed injuries may result in end-stage ankle arthritis excellent functional outcomes if syndesmosis is anatomically reduced Anatomy See complete ligament of ankle Ligaments distal tibiofibular syndesmosis includes anterior-inferior tibiofibular ligaments (AITFL) originates from anterolateral tubercle of tibia (Chaput's) inserts on anterior tubercle of fibula (Wagstaffe's) posterior-inferior tibiofibular ligament (PITFL) originates from posterior tubercle of tibia (Volkmann's) inserts on posterior part of lateral malleolus strongest component of syndesmosis interosseous membrane interosseous ligament (IOL) distal continuation of the interosseous membrane main restraint to proximal migration of the talus inferior transverse ligament (ITL) Syndesmosis Biomechanics function maintains integrity between tibia and fibula resists axial, rotational, and translational forces normal gait syndesmosis widens 1mm during gait deltoid ligament indirectly stabilizes the medial ankle mortise Presentation Symptoms anterolateral ankle pain proximal to AITFL may have medial sided ankle tenderness/swelling difficulty bearing weight lateral ankle sprains are often able to bear weight Physical exam palpation syndesmosis tenderness single best predictor for return to play provocative tests squeeze test (Hopkin's) compression of tibia and fibula at midcalf level causes pain at syndesmosis external rotation stress test pain over syndesmosis is elicited with external rotation/dorsiflexion of the foot with knee and hip flexed to 90 degrees Cotton widening of the syndesmosis with lateral pull on the fibula fibular translation anterior and posterior drawer force to the fibula with the tibia stabilized causes increased translation of the fibula and pain Imaging Radiographs recommended views AP, lateral, mortise view of ankle AP, lateral of entire tibia may show fracture of proximal fibula optional views external rotation stress radiograph gravity stress view will help determine competence of deltoid ligament contralateral ankle radiographs may help clarify syndesmosis widening versus normal anatomic variant findings decreased tibiofibular overlap normal >6 mm on AP view normal >1 mm on mortise view increased medial clear space normal less than or equal to 4 mm increased tibiofibular clear space normal <6 mm on both AP and mortise views CT indications clinical suspicion of syndesmotic injury with normal radiographs useful post-operatively to assess reduction of syndesmosis after fixation sensitivity and specificity more sensitive than radiographs for detecting minor degrees of syndesmotic injury MRI indications clinical suspicion of syndesmotic injury with normal radiographs sensitivity and specificity lambda sign described as being highly sensitive and specific for detecting syndesmotic injury Treatment of High Ankle Sprains Nonoperative non-weight-bearing CAM boot or cast for 2 to 3 weeks indications syndesmotic sprain without diastasis or ankle instability technique delayed weight-bearing until pain free physical therapy program using a brace that limits external rotation outcomes typically display a notoriously prolonged and highly variable recovery period recovery may extend to twice that of standard ankle sprain Operative syndesmosis screw fixation indications syndesmotic sprain (without fracture) with instability on stress radiographs syndesmotic sprain refractory to conservative treatment syndesmotic injury with associated fracture that remains unstable after fixation of fracture outcomes excellent functional outcomes if syndesmosis is accurately reduced often requires removal syndesmosis fixation with suture button indications same as for screw fixation technique fiberwire suture with two buttons tensioned around the syndesmosis may be performed in addition to a screw outcomes early results promising with some showing earlier return to activity when compared to screw fixation does not require removal Surgical Techniques Syndesmotic screw fixation technique two 3.5 or 4.5 mm syndesmotic screws through 3 or 4 cortices placed 2-5 cm above the plafond screw material no difference between stainless-steel and titanium screws bioabsorbable screws with similar outcomes number of cortices no difference between 3 or 4 cortices number of screws fixation with two screws is preferable position of foot during fixation a recent study challenges the principle of holding the ankle in maximal dorsiflexion to avoid overtightening postoperative typically non-weight-bearing for 6-12 weeks may prolong if screw breakage is a concern Complications Posttraumatic tibiofibular synostosis incidence ~10% after Weber C ankle fractures treatment surgical excision reserved for persistent pain that fails to respond to nonsurgical management ossification must be "cold" on bone scintigraphy prior to removal
QUESTIONS 1 of 6 1 2 3 4 5 6 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (SBQ07SM.2) A football player develops a synostosis between the distal tibia and fibula 8 months following treatment for a high ankle sprain. What is the most appropriate indication and timing for surgical excision? Tested Concept QID: 1387 Type & Select Correct Answer 1 Chronic lateral ankle instability at any time 1% (47/3235) 2 Progressive loss of plantar-flexion at any time 2% (77/3235) 3 Progressive loss of plantar-flexion and increased uptake on bone scan 2% (65/3235) 4 Persistent pain despite non-operative treatment and no uptake on bone scan 87% (2812/3235) 5 Persistent pain despite non-operative treatment and "hot" on bone scan 7% (217/3235) L 1 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review tested concept (OBQ06.74) A 21-year-old male collegiate basketball player presents with 1 year of left lower leg pain. The pain is worse with activity and the leg is tender to palpation. He denies constitutional symptoms, and conservative treatment has failed to provide relief. He denies recent trauma, but did sustain a severe ankle sprain 7 years ago. Radiograph, bone scan, and CT scans are shown in Figures A-D. What is the next most appropriate step in management? Tested Concept QID: 185 FIGURES: A B C D Type & Select Correct Answer 1 External beam irradiation with 60Gray to lesion 5% (155/3258) 2 Neoadjuvant multiagent chemotherapy followed by surgical resection of lesion followed by adjuvant multiagent chemotherapy 3% (108/3258) 3 Observation and repeat bone scans to plan external beam irradiation of 700cGray to lesion 3% (85/3258) 4 Indomethacin 25 mg PO tid for 6 weeks 9% (279/3258) 5 Observation and repeat bone scan followed by surgical resection if no increased uptake 80% (2620/3258) L 2 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review tested concept (OBQ05.88) Which test for acute syndesmotic injury of the ankle has the fewest false-positive results and smallest inter-observer variance when used intraoperatively? Tested Concept QID: 974 Type & Select Correct Answer 1 Squeeze test 2% (70/2801) 2 Fibular translation 4% (115/2801) 3 Cotton test 33% (924/2801) 4 External rotation stress test 60% (1674/2801) 5 Anterior drawer 0% (8/2801) L 3 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review tested concept
All Videos (8) Podcasts (1) Login to View Community Videos Login to View Community Videos 2019 Orthopaedic Summit Evolving Techniques Evolving Technique Update: 21-Year-Old Snowboarder After Falling Off A Rail: How I Assess Her Syndesmotic Ligament: 5 Tips In 5 Minutes - Gregory C. Berlet, MD Gregory C. Berlet Foot & Ankle - High Ankle Sprain & Syndesmosis Injury 12/15/2020 132 views 5.0 (1) Login to View Community Videos Login to View Community Videos 2019 Orthopaedic Summit Evolving Techniques Old School Syndesmosis Rigid Fixation Works Great, I Am Not Changing - Mark Easley, MD Foot & Ankle - High Ankle Sprain & Syndesmosis Injury 12/15/2020 104 views 0.0 (0) Login to View Community Videos Login to View Community Videos 2019 Orthopaedic Summit Evolving Techniques Old Man, Suture Fixation Techniques For The Syndesmosis Is Much Better - Troy Watson, MD Troy Watson Foot & Ankle - High Ankle Sprain & Syndesmosis Injury 12/15/2020 83 views 0.0 (0) Foot & Ankle⎪High Ankle Sprain & Syndesmosis Injury Team Orthobullets 4 Foot & Ankle - High Ankle Sprain & Syndesmosis Injury Listen Now 13:52 min 10/15/2019 396 plays 4.8 (5) See More See Less