Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Maisonneuve Fracture of the Fibula KEITH DOUGLAS MERRILL, M.D. Nine patients sustained a Maisonneuve fracture of the fibula (MFF), which is a proximal fibula fracture associated with an ankle fracture or deltoid ligament tear. Eight were treated with closed reduction and plaster casts. One was treated by open reduction and internal fixation. Reexamination was performed at an average of 25.7 months. This included subjective, objective, and functional evaluations, along with stress roentgenograms. Six patients had an excellent result, two a good result, and one a fair result. The MFF is often more stable than generally assumed. For injuries with only a partial syndesmotic disruption, nonoperative treatment is recommended. The Maisonneuve fracture of the fibula (MF'F) is often considered one of the most unstable ankle injuries. This is because of the presumed disruption of all the syndesmotic ligaments and the interosseous membrane from the ankle joint to the level of the fibula fracture.8,'0On those cases requiring surgery, exploration of the entire interosseous membrane is not feasible, and creating the injury in anatomic specimens is difficult. Therefore, little data exist concerning what structures are disrupted or how unstable the injury actually is. This study investigates the stability of Maisonneuve fractures and determines whether surgical intervention is routinely necessary. The syndesmotic ligaments (Fig. 1) con- From the University of Missouri Kansas City, Kansas City, Missouri. Reprint requests to Keith Douglas Memll, M.D., Department of Orthopaedic Surgery, Medical University of South Carolina, I7 1 Ashley Ave., Charleston, SC 29425. Received: March 5, 1991. Revised: August 2, 1991. Accepted: August 15, I99 1. necting the distal tibia to the distal fibula are three-dimensional and include the following, from anterior to posterior: the anterior tibiofibular ligament, the interosseous ligament, the posterior tibiofibular ligament, and the transverse tibiofibular ligament. The anterior tibiofibular ligament is the weakest of the complex. The interosseous ligament is triangular in shape, with its apex proximal and its base distal. It can be regarded as the fishtailed terminal portion of the interosseous membrane that extends from just below the fibular head to just above the ankle joint. The posterior tibiofibular ligament originates on the posterolateral aspect of the distal fibula and inserts into the posterolateral tubercle of the tibia. The transverse ligament originates from the digital fossa of the fibula and inserts across the entire posterior articular surface of the tibia. The majority of its insertion is medial to the posterolateral tubercle of the tibia. It is more elastic and stronger than the posterior tibiofibular ligament.4 On the medial side of the ankle, the deltoid ligament is divided into the superficial and deep portions. This superficial portion is fanshaped and can be divided into two parts: the tibionavicular and tibi~calcaneal.~ The deep deltoid is attached to the undersurface of the medial malleolus, is oriented horizontally, and attaches to the medial surface of the talus. With the above anatomic points in mind, one can imagine a plumb line dropped vertically through the center of rotation of the tibia and talus (Fig. I). The talus can externally rotate and the posterior ligamentous structures can maintain their integrity since they 218 Number 287 February, 1993 The Maisonneuve Fracture of the Fibula 219 I FIBULA CENTER OF ROTATION TIBIA , CENTER OF ROTATION HAL LEOLUS INTEROSSEOUS FIBULAR MALLEOLUS TERIOR TlBlOFlBULAR A i POSTERIOR TALOFIBULAR LIGAMENT LIGAMENT B TRANSVERSE TlBlOFlBULAR LIGAMENT FIGS. I A AND I B. The lateral (A) and end on views (B) ofthe ankle depicting the center of rotation ofthe talus. With external rotation of the talus the anterior ligaments will be disrupted, but the posterior ligaments can remain intact (Modified and printed with permission from Kelikian, A. S., and Kelikian, H.: Disorders of the Ankle. Philadelphia, W. B. Saunders, 1985, pp. 498 and 5 12). are not under tension with an external rotation force. This concept is extremely important in understanding the partial diastasis that often occurs with an external rotation injury. It also shows anatomically why the presence of tenderness anteromedially or anterolaterally cannot be interpreted as a complete ligamentous disruption, but examination for stability and possibly stress roentgenograms can be used to determine the degree of instability. In his discussion of ankle fractures, Wilson” states, “In general, the more proximal the fibula fracture, the greater the damage to the tibiofibular ligaments. The most extensive tearing is found with fractures of the proximal one-third of the fibula (Maisonneuve fracture) in which the interosseous membrane is usually torn as far proximally as the fibular fracture.” Pankovich* states, “This is a severe injury to the ankle, which includes complete diastasis of the distal tibiofibular syndesmosis and often rupture of the anteromedial joint capsule and deltoid ligament or fracture of the medial malleolus. Surgical treatment is necessary in later stages.” Bonnin,’ on the other hand, believes that in an MFF, the interosseous ligament, the interosseous membrane, and the posterior tibiofibular ligament are intact. He classifies it as a partial diastasis that is relatively stable, and believes that surgery is not necessary.’ MATERIALS AND METHODS From 1980 until 1986, 1 1 patients with MFF were treated at several Kansas City hospitals. Two of these fractures occurred within four months of the review and were excluded from the study group. Examination of nine patients ranged from eight months to 4.5 years (average, 25.7 months). In seven of the nine, clinical examination and external rotation stress roentgenograms were completed. A special jig was used to ensure standard roentgenograms as recommended by Bolin,’ and the mortise roentgenograms were made with the foot in 20” of internal rotation. In the other two, a review of the chart and roentgenograms and a telephone interview were conducted. Baseball, softball, and slipping on ice or water accounted for most of the injuries. In all nine cases, the fracture occurred in the proximal one third of the fibula, and the patients’ symptom was ankle pain. Four of the nine patients (44%) were able to bear weight on the injured extremity with an antalgic gait and came for evaluation between one day and three weeks after injury. One patient 220 Clinical Orthopaedics and Related Research Merrill had an associated medial malleolus fracture and eight (89%) had ligamentous injuries medially, based on tenderness and swelling found in the region of the anteromedial capsule. In four of nine (44%),the diagnosis was missed by the initial physicians because they focused their attention toward the sore ankle and did not examine or obtain roentgenograms of the proximal fibula. Four of the nine (44%)had nondisplaced or minimally displaced fractures of the posterolateral tubercle of the tibia, none greater than 10% of the articular surface. All four of these were treated nonoperatively. Eight of nine (89%) were treated by closed reduction and casting; six in short leg casts for four to eight weeks, and two in long leg casts for six to eight weeks. One was treated by joint exploration, deltoid ligament repair, and insertion of a syndesmotic screw. The treatment was determined by the treating physician’s preference. At the time of the most recent examination, eight of nine (89%) had resumed their preinjury activity level, including roller skating, basketball, softball, and construction work. The one patient who did not return to his previous occupation had a peroneal nerve palsy since the injury and could not return to house painting. The etiology of the palsy was not identified. In the seven patients reexamined, the range of motion (ROM) in the ankle and subtalar joints was equal to that of the contralateral side. On follow-up roentgenogram, eight of nine (89%) showed no increase in the medial clear space or in the syndesmosis. One had a I-mm increase in the medial clear space. One patient had mild subchondral sclerosis of the distal tibia and was the only patient with any roentgenographic arthrosis. The talocrural angle was used to evaluate fibular length. This angle is formed by the intersection of two lines, one drawn parallel to the tibial articular surface and the second drawn between the tips of the malleoli on the mortise roentgenogram.’ It was within 2” of the contralateral uninjured ankle in all cases. This is considered normal.’ Six patients (67%)were judged to have an excellent result (returned to preinjury activities with no more than mild occasional discomfort and no roentgenographic abnormalities). Two patients (22%) had a good result (mild roentgenographic abnormalities) and one ( 1 1%) had a fair result (peroneal nerve palsy). DISCUSSION Maisonneuve6 published the results of his experiments on the ankle in 1840. The illustration depicting the injury that bears his name shows the proximal fibula fracture and also shows the interosseous membrane intact (Fig. 2). In the same illustration, the analogy between the fracture and two volumes of a book with an external rotation force applied between them is shown. This demonstrates the posterior hinge around which one volume rotates. The posterior hinge in the fracture is the posterior tibiofibular ligament and the transverse ligament. Even with a fracture of the posterolateral tubercle of the tibia, which rarely involves more than one fourth of the tibial vault, the transverse ligament will maintain the integrity of the posterior syndesmosis because of its insertion across the entire posterior tibial surface. It will provide a posterior hinge for the syndesmosis.’ LaugeHansen5 describes a proximal fibula fracture HINGED - POSTERlOAL” FIG. 2 . Maisonneuve’s conception of the fracture that bears his name, and conceptualization of an external rotation force between two books, hinged posteriorly and opening anteriorly. Inset below also shows external rotation of the fibula and disruption of the anterior ligamentous structures (Modified and printed with permission from Kelikian, A. S., and Kelikian, H.: Disorders of the Ankle. Philadelphia, W. B. Saunders, 1985, p. 116). Number 287 February, 1993 caused by external rotation of the foot with the dorsal ligaments of the syndesmosis intact, which is a description of a partial diastasis. Pankovich' created the Maisonneuve fracture in anatomic specimens. He found the interosseous membrane intact in the cases he was able to create. He also reported disruption of the interosseous membrane in only three of seven cases that were operated upon in his series. Approximately one half of his patients were treated nonoperatively. Despite these findings, Pankovich' considered the Maisonneuve fracture a severe injury to the ankle with complete diastasis of the syndesmosis and recommended surgical treatment. It is easy to understand how the posterior ligamentous structures can remain intact with an external rotation injury resulting in a partial syndesmotic diastasis. It is slightly more difficult to understand how the interosseous membrane could remain intact with a fracture of the proximal fibula. The interosseous membrane is a fascia1 structure connecting the tibia and fibula in one plane, preventing lateral displacement of the fibula but doing little to prevent anterior and posterior displacement of the fibula.2 Also, because of its linear insertion, the interosseous membrane affords little rotational control to the fibula, and can remain intact while the fibula rotates. The proximal fibula fracture occurs when the rotation of the fibula is prevented by the capsuloligamentous structures of the proximal tibiofibular joint. In an anatomic specimen, the entire proximal and distal syndesmotic ligaments and joint capsules were cut, leaving only the interosseous membrane intact between the tibia and fibula. The fibula could be easily rotated externally approximately 150" without disruption of the interosseous membrane. The interosseous membrane was easily disrupted by applying an abduction force to the distal fibula. The clinical, roentgenographic, and surgical findings of a patient seen recently with a Maisonneuve fracture demonstrate the par- The Maisonneuve Fracture of the Fibula 221 tial diastasis that can occur with this injury. The patient sustained an external rotation injury to his ankle while moving furniture late at night. The next day he came to the hospital with pain, swelling, and tenderness in the anteromedial and anterolateral aspects of his ankle. Initial ankle roentgenograms showed slight widening of the medial clear space. Roentgenogram of the knee showed the FIG. 3 . Abduction stress roentgenograms of a patient with a Maisonneuve fracture, showing that the medial clear space is widened to approximately 5 mm. 222 Clinical Orthopaedics and Related Research Merrill proximal fibula fracture. Stress roentgenograms showed that the medial clear space opened to 5 mm with straight abduction (Fig. 3), and to 7 mm with external rotation of the foot (Fig. 4). T FIG. 5. Internal rotation, valgus stress roentgenograms of the same ankle demonstrating closing of the medial clear space. Anatomic reduction with the above force demonstrates the presence of an intact posterior hinge that with internal rotation of the foot closes the book and prevents lateral subluxation. FIG. 4.External rotation stress roentgenographs of same patient demonstrating increased widening of the medial clear space. A mortise-view roentgenogram with internal rotation of the foot on the tibia and application of a valgus force showed anatomic reduction of the talus. This finding demonstrated the presence of the posterior hinge between the tibia and fibula (under tension because of the internal rotation of the foot) and prevented lateral subluxation of the talus (Fig. 5). Because this patient’s transient lifestyle limited his availability for close follow-up care with the authors, ankle exploration and ligament repair were performed. The findings at operation included avulsion of the anterior capsule and the anterior one half of the super- Number 287 February. 1993 ficial deltoid ligament from the tibia, and disruption of the anterior one third of the deep deltoid ligament with the posterior two thirds intact. On the lateral side the anterior tibiofibular ligament was disrupted, and the interosseous ligament was disrupted. A nerve hook was used to probe the posterior syndesmotic ligaments, which were intact. The interosseous membrane was intact where it was probed, just proximal to the syndesmosis. The anterior capsule, the deltoid ligament, and the anterior tibiofibular ligament were repaired. An external-rotation stress roentgenogram showed anatomic reduction. Gentle lateral traction applied to a bone hook around the distal fibula caused no displacement of the fibula. Therefore, no syndesmotic screw was thought necessary based on the recommendation of De Souza et aL3 Muller et al.,’ and Pankovich.8 This series of patients with Maisonneuve fractures, the above-described roentgenographic and surgical findings, along with a review of the literature, show that the Maisonneuve fracture can, and often does occur with a partial syndesmotic diastasis. These injuries are relatively stable, and they can be The Maisonneuve Fracture of the Fibula 223 treated nonoperatively by internally rotating the foot and thus using the posterior hinge to “close the book”, yielding an anatomic reduction. REFERENCES I . Bolin, H.: The fibula and its relationship to the tibia and talus in injuries ofthe ankle due to forced external rotation. Acta Radiol. 56:439. I96 1. 2. Bonnin, J. G.: Injuries to the ankle. London, Heineman Medical Books, 1950, pp. 163-164. 3. De Souza, L. J., Gustilo, R. B.. and Meyer, T. J.: Results of operative treatment of displaced external rotation-abduction fractures of the ankle. J. Bone Joint Surg. 67A: 7, 1066, 1985. 4. Kelikian, A. S., and Kelikian, H.: Disorders of the Ankle.St. Louis, W.B. Saunders, 1985.pp.6. 15-18. 478, 499. 5. Lauge-Hansen, N.: Fractures of the ankle. Arch. Surg. 56:259, 1948. 6. Maisonneuve, M. J. G.: Recherches sur la fracture du perone. Arch. Gen. Med. 7:165,433. 1840. 7. Muller, M. E.. Allgower. M.. Schneider. R.. and Willenegger, H.: Manual of Internal Fixation, ed. 2. Berlin, Springer-Verlag, 1979. p. 296. 8. Pankovich, A. M.: Maisonneuve fractures of the fibula. J. Bone Joint Surg. 58:3. 337, 1976. 9. Sarkisian, J. S., and Cody, G. W.: Closed treatment of ankle fractures: A new criterion for evaluation: A review of 250 cases. J. Trauma 16:323. 1976. 10. Wilson, F. C.: Fractures and dislocations of the ankle. In Rockwood, C. A,, and Green, D. P. (eds.): Fractures in Adults. vol. 2, ed. 2. Philadelphia. J. B. Lippincott, 1984. p. 1674.