SLR - April 2015 - Brandon Barrett
Reference: Kwon JY, Gitajn IL, Walton P, Miller T, Appleton P, Rodriguez EK. A Cadaver Study Revisiting the Original Methodology of Lauge-Hansen and a Commentary on Modern Usage. JBJS. 2015 Apr; 97(7): 604-9.Scientific Literature Review
Reviewed By: Brandon Barrett, DPM
Residency Program: Mount Auburn Medical Center
Podiatric Relevance: When it comes to ankle trauma the Lauge-Hansen (LH) classification is quickly referenced among orthopaedic and podiatric surgeons. It comes from a landmark study done in the1950s. The study used cadaveric limbs to demonstrate the characteristics and pathomechanics in ankle fractures, depending on the foot position and the vector of force. It claimed consistency and reproducibility of its results. This presented a classification for ankle fractures that has endured over the past 60 years even though several articles looking at the biomechanical, radiographic and video analyses have failed to validate its original findings. The purpose of this study was to recreate LH’s original work on cadaveric specimens, specifically looking at the SER mechanism of injury. It was hypothesized that the SER mechanism would not reliably and consistently produce the predicted sequence of osseous and soft tissue injury stated in the LH classification.
Methods: This is a cadaveric study of 10 fresh-frozen cadaveric specimens, amputated above the knee, with no history of ankle pathology. Mean age of donors was 65 years old. Bone density tests were performed on all specimens. Like in the LH study, the soft tissue was removed to the level of fascia on the dorsum of the foot, the ankle and the distal 10 cm of the leg. All feet were fixated to plywood with screws and the femur was fixed in a vise such that the knee was bent at a 45° angle. The foot was placed in maximum supination with the ankle in neutral position. A manual external force was then quickly applied until a crack or tear was felt or heard. Fluoroscopic imagine was then used to deem whether the ankle was grossly unstable.If it was not then the experiment continued until evidence of gross instability could be demonstrated.
Results: None of the limbs were osteoporotic. No specimens demonstrated an anterior fibular or tibia avulsion fracture, while only two demonstrated injury to the AITFL as described by LH stage I. Four specimens showed a short oblique fracture that is described in LH stage II with two of these being the two that fulfilled LH stage I. One specimen had disruption of the PITFL and none had a posterior malleolar fracture, therefore only one of the ten specimens following all three stages of the LH classification. Five of the ten specimens exhibited an injury characteristic of LH stage IV, but no specimen exhibited the complete pattern for a LH stage IV injury.
Conclusions: While LH helped create an understanding on how ankle fracture patterns are produced, his classification may oversimplify the actual pathomechanics that cause these injuries. As demonstrated in this study, a pure supination-eversion force applied to the foot does not result in an injury pattern described by LH that follows through all four stages. Other studies have shown that in vivo fracture patterns only follow LH’s staging system only half of the time. While the LH classification is a useful staging system to be familiar with in both academics settings and in practice, it has questionable validity and should not be used as an isolated predictor of ankle osseous and soft tissue injury.