A cadaver study revisiting the original methodology of Lauge-Hansen and a commentary on modern usage.

BACKGROUND: The study by Lauge-Hansen published in the Archives of Surgery in 1950 still stands as the seminal work for our understanding of the pathomechanics of ankle fractures. The purpose of the present study was to recreate Lauge-Hansen's experiments for the supination-external rotation (SER) fracture mechanism and to determine whether the predicted sequence of osseous and soft-tissue injury is reproducible on the basis of his originally described methodology. METHODS: Ten fresh-frozen cadaver specimens amputated above the knee were utilized. The foot was axially loaded in a position of neutral dorsiflexion and supination. External rotation was applied manually in accordance with Lauge-Hansen's description until osseous and/or soft-tissue injury occurred. Fluoroscopic images were made and anatomic dissection was performed. RESULTS: Although several specimens exhibited findings consistent with certain stages of the SER injury pattern, no specimen demonstrated the complete sequence of predicted osseous and soft-tissue injury. CONCLUSIONS: Loading cadaver specimens with an SER mechanism utilizing a methodology similar to that in the original experiments by Lauge-Hansen does not reliably produce the sequence of osseous and soft-tissue injury predicted by Lauge-Hansen.

Evaluation of the integrity of the deltoid ligament in supination external rotation ankle fractures: a systematic review of the literature.

BACKGROUND AND PURPOSE: Review the literature concerning modalities to evaluate the integrity of the deltoid ligament in patients with supination external rotation ankle fractures. METHODS: The electronic databases Pubmed/Medline, CINAHL and Embase were searched from 1987 to November 2007 to identify all published original studies concerning diagnostic modalities to evaluate the integrity of the deltoid ligament in adult ankle fractures. RESULTS: This review included nine studies involving 423 ankle fractures. Three trails investigated medial tenderness; two studies, ecchymosis; two studies, swelling; one study, an injury radiograph; six studies, a type of radiographic stress view; one study, the Lauge-Hansen classification; one study, MRI; and one article studied arthroscopy in the evaluation of the deltoid ligament integrity. INTERPRETATION: Swelling, ecchymosis, medial tenderness, initial injury radiographs and the Lauge-Hansen classification are less adequate predictors of the integrity of the deltoid ligament. Manual or the less painful variant, the gravity external rotation stress radiographs are considered the gold standard. The amount of medial clear space widening indicative of a positive external rotation stress test has been somewhat variable in the literature but > or =5 mm is generally regarded as most reliable. Achieving adequate external rotation of the foot when obtaining stress radiographs is more important than positioning the ankle in the appropriate degree of ankle flexion. The amount of applied force necessary when performing an external rotation stress radiograph is not well defined and mainly determined by the patient's pain level. The indication for surgery should not be based on the absolute value of one parameter but on the combination of several parameters. If nonoperative treatment is chosen despite a positive stress radiograph, close follow-up is critical because subluxation of the ankle joint is still possible. MRI could be useful in individual cases.

[The role of the tibiofibular syndesmotic and the deltoid ligaments in stabilizing Weber B type ankle joint fractures--an experimental investigation]. / Beitrag der Syndesmosen und des Deltabandes zur Stabilität der Aussenknöchelfraktur Typ Weber B. Eine experimentelle Untersuchung.

The purpose of the present biomechanical investigation was to check the functional importance of the syndesmosis ligaments and of the deltoid ligament for ankle fracture type B according to the AO-Weber classification. We constructed a special fixation clamp, with 12 fresh and unembalmed lower legs being tested for lateral shift (mm) and ten for tibiotalar rotation. All specimens were exposed in the same neutral position. Transverse loads (F(y)) varied between 0 and 150 N, axial loads (F(z)) between 0, 300, 600 and 1,000 N and rotational loads (F(r)) between 2.4 and 4.9 Nm. All series were repeated according to supination-eversion (SE) injury patterns of the Lauge-Hansen classification. Syndesmotic ligaments and the fibula were incrementally sectioned from anterior to posterior. Type SE I consisted of an isolated incision of the anterior syndesmosis ligament. Type SE II had an additional oblique fracture of the fibula at the height of the tibiofibular syndesmosis. In type SE III injuries, in addition to the fibular fracture, a complete rupture of the syndesmosis ligaments was present, and for type SE IV lesions the deltoid ligaments were incised. The transverse load-displacement curve was s-shaped in all uninjured joints,with the highest gradient between 10 and 20 N with no axial compression. Without axial compression in cases of F(y)=25 N transverse loads, the mean talus translation was 0.51 mm. Following type II injuries, the average talus translation was 0.68 mm (not significant) and rose to an average of 0.95 mm ( P <0.01) in type III injuries. After additional incision of the deltoid ligaments, the ankle joint subluxed permanently when more than 5-10 N transverse loads were applied. Axial loads of 300 N or more resulted in a considerable reduction in talus translations, indicating increased stability and congruency within the joint complex. In this way, the vertical loading of the ankle joints always contributed to joint stability. The average internal tibiotalar rotation reached with a torque of 2.4 Nm was 3.52 degrees and with 4.9 Nm 5.15 degrees when no axial compression was applied. External rotation measured -6.36 degrees and -8.62 degrees, respectively. Following the experimental protocol, significant increases were noted for external rotation at SE II degrees injuries ( P =0.003) and for internal rotation at SE III degrees ( P =0.03) injuries. Our data support the proposition that the deltoid ligaments and the posterior syndesmosis play a key role in the stability of ankle fractures for supination-eversion injuries. If these structures remain intact, conservative and early functional treatment are recommended in patients with minimal (<2 mm) or no fracture displacement. This concept is confirmed by the literature dealing with clinical mid- and long-term follow-up studies.