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Management of Posterior Malleolar Fractures: A Systematic Review
The Journal of Foot & Ankle Surgery 55 (2016) 140–145
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The Journal of Foot & Ankle Surgery journal homepage: www.jfas.org
Review
Management of Posterior Malleolar Fractures: A Systematic Review Saurabh Odak, MBBS, MRCS 1, Raju Ahluwalia, MB ChB, FRCS 2, Puthanveettil Unnikrishnan, MBBS, MRCS 1, Michael Hennessy, BSc, MB ChB, FRCS 3, Simon Platt, MB ChB, FRCS 3 1 2 3
Specialist Trainee, Trauma and Orthopaedics, Warrington Hospital, Cheshire, United Kingdom Consultant Orthopaedic Surgeon, Kings College London, London, United Kingdom Consultant Orthopaedic Surgeon, Arrowe Park Hospital, Wirral, United Kingdom
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 3
Posterior malleolar fractures are relatively common and usually result from rotational ankle injuries. Although treatment of associated lateral and medial structures is well established, several controversies exist in the management of posterior malleolus fractures. We performed a systematic review of the current published data with regard to the diagnosis, management, and prognosis of posterior malleolus fractures. A total of 33 studies (8 biomechanical and 25 clinical) with >950 patients were reviewed. The outcome of ankle fractures with posterior malleolar involvement was poor; however, the evidence was not enough to prove that the size of the posterior malleolus affects the outcome. Significant heterogeneity was noted in the cutoff size of the posterior malleolar fragment in determining management. The outcome was related to other factors, such as fracture displacement, congruency of the articular surface, and residual tibiotalar subluxation. Indirect evidence showed that large fracture fragments were associated with fracture dislocations and ankle instability and, thus, might require surgical fixation. We have concluded that the evidence to prove that the size of the posterior malleolar affects the outcome of ankle fractures is not enough, and the decision to treat these fractures should be determined by other factors, as stated previously. Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: ankle fractures outcome talus tibia trimalleolar fracture Volkmann’s fracture
Ankle fractures account for about 4% of all body fractures, with an annual incidence of 124 per 10,000 persons in the United Kingdom (1,2). More than one third of these fractures will involve the posterior malleolus with several variants described in published studies (1). The current published data suggest a poor outcome for ankle fractures involving the posterior malleolus (3–9). Although the management of associated medial and lateral structures is well established, the management of the posterior malleolus fractures remains controversial. Currently, no clear consensus has been reached regarding the indications of the operative and nonoperative management of these fractures with the decision often determined by the size of the fragment. We performed a systematic review of the English-language published data to assess the outcome of ankle fractures treated operatively and nonoperatively and involving the posterior malleolus. We
Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Saurabh Odak, MBBS, MRCS, Trauma and Orthopaedics, Warrington Hospital, 2 Ward Close, Great Sankey, Warrington, Cheshire WA5 8XY, UK. E-mail address: [email protected] (S. Odak).
also assessed the factors affecting the outcome, including the fragment size, which could guide the treating surgeon in the management of these injuries.
Materials and Methods The review incorporated an electronic search of the MedlineÒ database using PubMedÒ as the search engine (U.S. National Institutes of Health, National Library of Medicine) and EmbaseÒ (Elsevier BV, Amsterdam, The Netherlands), the Cochrane Library (John Wiley & Sons, West Sussex, UK), ProQuestÒ (ProQuest, Ann Arbor, MI). We included all the studies published from January 1966 to July 2014. We used the following search terms: posterior malleolar fractures, trimalleolar fractures, and Volkmann’s fractures. In addition, the appropriate MeSH terms of assessment, diagnosis, evaluation, prognosis, outcomes, management, and treatment were entered and Boolean operators used. We limited our search to studies published in the English language only. Three of us (S.O., R.A., P.U.) independently evaluated the abstracts for scientific content and quality. Our inclusion criteria were any clinical and/or biomechanical studies that included posterior malleolus fractures and the evaluation, diagnosis, management, and prognosis. Once the abstract was found suitable, the study was retrieved and thoroughly evaluated. The references in the retrieved studies were manually checked to find additional relevant publications. Finally, the published proceedings of recent scientific meetings and conferences were followed, along with a manual search of current orthopedic textbooks (10,11). We excluded studies in which posterior malleolus fractures were associated
1067-2516/$ - see front matter Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved. http://dx.doi.org/10.1053/j.jfas.2015.04.001
S. Odak et al. / The Journal of Foot & Ankle Surgery 55 (2016) 140–145
with tibial shaft fractures, distal tibial metaphyseal fractures (pilon fractures), stress fractures, open and pathologic fractures, and case reports, technical notes, and tips. Data Extraction The data extracted included the demographic details of the patients, diagnosis, and treatment, including nonoperative and operative treatment. When assessing these patients, we included all the methods of nonoperative and operative treatment, irrespective of the method of treatment and fixation and the approach used. We included all the outcome measures described in the present study, including ankle osteoarthritis and objective measures such as the visual analog scale for pain (12–14), the Olerud and Mollander scores (15), the American Orthopedic Foot and Ankle Society scores (16,17), and Cedell’s scores, when available (18). Finally, we addressed the prognostic implications of posterior malleolus size in the final outcome of these injuries. Data were collected on a Microsoft OfficeÒ Excel spreadsheet, edition 2013 (Microsoft, Redmond, WA).
Results The initial search identified a total of 158 relevant citations; however, further scrutiny led to the exclusion of 125 studies (79.1%). Thus, 33 studies met the inclusion criteria, of which 8 (25.2%) were biomechanical and 25 (75.7%) were clinical studies. All the studies assessed were case series, and no randomized trials were identified during the analysis.
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Fitzpatrick et al (28) noted that with posterior malleolus fractures involving 50% of the articular surface, the contact stress redistributed to a more anterior and medial portion of the ankle joint. The investigators concluded that the peak stress redistribution with large posterior malleolus fractures led to abnormal loading of the tibiotalar joint and thus could lead to the development of post-traumatic ankle arthrosis (28). However, no conclusion was derived to explain why the abnormal load redistribution ensued even after adequate fracture fixation. Summary of Biomechanical Studies The results of the biomechanical studies have confirmed that posterior ankle stability is predominantly provided by anterior inferior tibiofibular ligament, posterior inferior tibiofibular ligament, and medial and lateral structures with little contribution from posterior malleolus. Although in itself the posterior malleolus might not be involved in significant load bearing at the tibiotalar joint, with posterior malleolus fractures, the redistribution of the load is abnormal, which might predispose the patient to the development of posttraumatic arthritis. Clinical Studies
Biomechanical Studies A total of 8 studies (25.2%) were identified that assessed the role of the posterior malleolus in ankle stability and joint loading. A synopsis of these studies follows. Scheidt et al (19) showed that a posterior malleolus fracture measuring 25% of the distal tibial articular surface led to posterior translation of the talus with an axial loads of 15 kg (150 N), and fixation of these fractures reduced posterior instability, provided the posterior inferior tibiofibular ligament was intact. However, the findings of the present study were contradicted by Raasch et al (20), who demonstrated that osteotomizing 40% of the posterolateral tibial margin did not significantly increase the posterior translation of the talus by a posteriorly directed force of 200 N, as long as the anterior inferior tibiofibular ligament and lateral malleolus were intact (20). This was further confirmed by Harper (21), who did not find a significant posterior talar translation with a posterior malleolus fracture measuring 50% of the distal tibial articular surface. However, in the setting of a combined disruption of the lateral and medial ligamentous structures, significant posterior translation of the talus occurred (21–23). Papachristou et al (24), using photoelastic bone models, showed that during axial loading of the distal tibial articular surface, the load was concentrated only in the middle 50% and not in the posterior 25% of the articular surface. They thus concluded that the posterior malleolus might not be involved in load bearing. Macko et al (25) noted decreased joint contact area as the size of the posterior malleolus fracture increased to >33% of the distal tibial surface with the ankle in neutral or 10 of dorsiflexion. They concluded that this increase in focal load concentration at the tibiotalar joint might predispose to early post-traumatic degenerative changes. Hartford et al (26) agreed with these findings, reporting that an increasing posterior malleolus fracture size decreased the tibiotalar contact area, which was not affected by the integrity of the deltoid ligament. Both studies support the concept that an increasing posterior malleolus fracture size diminished the tibiotalar joint contact area (25,26). In contrast, Vrahas et al (27) noted that even after removing 40% of the posterior malleolus, the peak contact stress did not change. They thus hypothesized that even with a posterior malleolar malunion stress would not increase beyond the physiologic limits and might not contribute to the development of post-traumatic arthrosis (27).
A total of 960 patients from 25 studies with posterior malleolar fractures were included in the present review. Of the 960 patients, 288 were female and 219 were male patients from 16 studies; however, 9 studies with 453 patients did not report the gender distribution. The mean age was 45.48 (range 13 to 84) years. In most of the studies, the diagnosis and size of the posterior malleolus fracture was made from the lateral radiograph of the ankle. In 915 patients, the posterior malleolus was a part of combined injuries (i.e., anterior, medial, lateral, and/or syndesmotic structures), and in 45 patients, it was isolated (29–31). Diagnosis and Classification of Posterior Malleolus Fractures Standard anteroposterior and lateral ankle radiographs were used in the diagnosis of these injuries in most of the studies. However, the reliability of using lateral radiographs in accurately determining the size of the posterior malleolus fragment has been questioned (25,32). Haraguchi et al (33) classified posterior malleolus fractures using computed tomography into 3 types: 1. Posterolateral oblique type (67%) 2. Medial extension type (19%) 3. Small shell type (14%)
Variants of Posterior Malleolar Fracture Two studies (17 patients) described a separate variant of the posterior malleolus fracture that involved the posteromedial distal tibial articular surface (34,35), along with medial and/or lateral injuries. All these variant fractures underwent open reduction and internal fixation using either a posterolateral or a posteromedial approach, and the investigators reported satisfactory outcomes. A recent study by Switaj et al (32) reported a 20% incidence of posterior malleolus variant (termed the “posterior pilon variant”) in operatively treated ankle fractures. Isolated Posterior Malleolus Fractures Three separate studies involving 45 patients assessed isolated posterior malleolus fractures (29–31). All the fractures were managed conservatively, and all the studies had a relatively long follow-up period. The fragment size ranged from 3% to 47% of the distal tibial
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articular surface. Only 1 patient developed severe (grade 2) ankle arthrosis, and only 2 patients complained of severe ankle pain. One study reported excellent or good Olerud and Mollander scores, Cedell’s score, and ankle range of motion scores in most patients (18 of 23 patients, 78.2%). The investigators thus advocated conservative treatment of isolated posterior malleolar fractures (29–31). Combined Ankle Injuries That Included Posterior Malleolus Fractures We examined the results of both operative and nonoperative management strategies to determine their benefit in the treatment of posterior malleolus fracture. Nonoperative Treatment. In all, 419 patients (45.8%) from 13 studies (Table 1) had ankle fractures in which the posterior malleolus fracture was treated nonoperatively in conjunction with surgically treated medial or lateral fractures (2,4–8,23,36–42). In 2 studies, the number of patients treated nonoperatively was not specified (4,42). The size of the posterior malleolus fragment varied from 5% to 55% of the distal tibial articular surface in this group. Significant heterogeneity was noted regarding the cutoff size of the posterior malleolus fragment chosen for conservative management. In general, smaller posterior malleolus fractures were treated nonoperatively (2,4–8,23,36–38,43). Only a few studies reported the outcomes of nonoperative treatment of posterior malleolus fractures solely according to the size of the fragment. However, the size of the posterior malleolus fragment in these studies ranged from 4% to 39% (2,8,23). The overall prognosis for conservatively treated trimalleolar ankle fractures was poorer than that of conservatively treated bimalleolar fractures. The incidence of post-traumatic arthritis was reported to be 29.8% in the nonoperatively treated group (7,38). No association was found between the size of the posterior malleolus fragment and the incidence of post-traumatic arthritis. Operative Treatment. A total of 16 studies with 452 patients (Table 2) reported on operative treatment (2,4–8,23,33,36–44). In 2 studies, the number of patients treated surgically was not specified (4,42). In
the studies that included a nonoperative and operative arm, the large posterior malleolus fragments were surgically fixed. The cutoff size of the posterior malleolus fragment fixed surgically ranged from 10% to 25% of the distal articular surface. Several methods of fixation and surgical approaches were described; however, anteroposterior screw fixation was the most common method of fixation (2,4,35). Posteroanterior plate osteosynthesis with a posterolateral approach for larger or comminuted fragments was also described, with several investigators reporting good results (35,36,40). The incidence of post-traumatic arthritis was reported to be 40% in this group. Just as with the previous group of patients, we did not find any association between the size of the posterior malleolar fragment and the incidence of post-traumatic arthritis. However, the outcomes were associated with congruity of the joint surface and stability of the ankle joint after fixation (2,5,38). Incidence of Osteoarthritis The analysis confirmed a high overall rate of clinical and/or radiologic osteoarthritis after these injuries (33.5%). Although the incidence of post-traumatic arthritis was greater in the surgical group (Table 3), we believe that that was not a true representation. This was because of the small number of patients and multiple confounding factors such as the choice of intervention, inconclusive classification, nonstandardized outcome measures, and many studies only reporting short-term follow-up periods. The factors associated with a greater incidence of post-traumatic osteoarthritis were fracture dislocations on initial presentation, congruency of the distal tibial articular surface, and residual talar subluxation after the treatment. The size of the posterior malleolus fragment was not associated with the incidence of post-traumatic osteoarthritis in the 2 groups. Discussion Although numerous studies have confirmed a poor prognosis for ankle fractures involving the posterior malleolus, controversies still exist regarding the appropriate management and indications for
Table 1 Studies in which posterior malleolus fractures were treated nonoperatively (13 studies were identified, with a total of 419 ankle fractures) Investigator
Patients With PM Fractures Treated Nonoperatively
Average PM Fragment Size in Whole Group (%)
Average PM Fragment Size Treated Conservatively (%)
Conservative Treatment Used
Weightbearing Status
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
60 (58.8) 27 (60)
NR NR
12.5 4.9 NR
NR Cast immobilization (3 to 4 wk)
Jaskulka et al (7) (n ¼ 62) McDaniel and Wilson (5) (n ¼ 51)
48 (77.4) 44 (86.2)
NR NR
NR NR
de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper (21) (n ¼ 38) Bauer et al (43) (n ¼ 33)
34 43 23 10
19.4 (3 to 49) NR 30.34 (25 to 45) NR
NR NR 28.52 (25 to 39) NR
Broos and Bisschop (6) (n ¼ 178)
78 (43.8)
NR
de Souza et al (41) (n ¼ 46)
14 (30.4)
NR
NR; however, all fractures were 33 NR
Below-the-knee cast for mean of 10 wk Above-the-knee cast for mean of 8 wk; total of 11 wk in cast NR NR Cast or splint for mean of 8 wk Percutaneous hook test to assess stability under anesthesia; closed reduction and cast for 6 wk NR
NR Non-weightbearing for 8 (range 4 to 12) wk 3 wk NR
Tejwani et al (8) (n ¼ 54) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR)
34 (62.9) NR NR
NR NR NR
16.1 (4 to 28) NR NR
(75.5) (75.4) (60.5) (30.3)
Abbreviations: NR, not reported; PM, posterior malleolar. Data presented as n (%), % (range), or mean standard deviation, unless otherwise noted. Nonoperative treatment consisted of cast immobilization for 4 to 11 weeks.
Short cast for 8 wk
NR Below-the-knee cast for 6 wk Below-the-knee walking cast of Sarmiento type for 6 wk
NR NR NR 6 wk
NR Non-weightbearing 2 wk; partial weightbearing 2 wk; full weightbearing 4 wk 6 wk 6 wk Immediate post-ankle fixation
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Table 2 Results of 16 studies (n ¼ 452 patients) in which operative intervention was undertaken Investigator
Patients With PM Fractures Treated Operatively
Average PM Fragment Size Treated Operatively (%)
Fixation Type
Approach
Anteroposterior, 19; posteroanterior, 23 Cortical screws, 4; partially threaded cannulated screws, 11 Anteromedial screw fixation
NR Anteroposterior, 15; posterolateral, 3
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
42 (41.1) 18 (40)
28.5 9.2 NR
Jaskulka et al (7) (n ¼ 62)
14 (22.5)
NR
McDaniel and Wilson (5) (n ¼ 51) de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper et al (21) (n ¼ 38) Bauer et al (43) (n ¼ 33) Broos and Bisschop (6) (n ¼ 178) de Souza et al (41) (n ¼ 46) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR) Abdelgawad et al (44) (n ¼ 12)
7 11 14 15 23 100 14 NR NR 12
(13.7) (24.4) (24.5) (39.4) (69.6) (56.1) (30.4)
(100)
All 25 NR NR 31.33 NR NR NR NR NR All 30
Papachristou et al (24) (n ¼ 15) Haraguchi et al (33) (n ¼ 57)
15 (100) 57 (100)
Miller et al (40) (n ¼ 18) Tejwani et al (8) (n ¼ 54)
18 (100) 20 (37)
25 to 33 Posterolateral oblique type, 11.7; medial extension type, 29.7 NR 25.2 (16 to 38.1)
Heim (39) (n ¼ 60)
60 (100)
NR
Screw fixation NR NR Screw fixation, 14; Steinmann, 1 NR Screw fixation Screw fixation, 11; wiring of PM, 1 NR NR Primary open reduction internal fixation, 10; revision fixation, 2 Open reduction internal fixation Open reduction internal fixation
Open reduction internal fixation Indirect reduction, anteroposterior screw fixation (n ¼ 10); open reduction, direct internal fixation (n ¼ 10) NR
Anteromedial and extension of medial malleolar incision Anteroposterior NR NR NR NR NR Front to back NR NR Posterolateral Posterolateral; posteromedial NR
Posterolateral Posterolateral (n ¼ 10)
NR
Abbreviations: NR, not reported; PM, posterior malleolar. Data presented as n (%), % (range), or mean standard deviation, unless otherwise noted.
fixation in these fractures. Traditionally, the size of the posterior malleolus has been used as a guide for the management of these fractures. However, a recent study by Gardner et al (35) suggested that significant variations exist in the management of posterior malleolus fractures among clinicians, with various factors and size considered for surgical fixation. Our review has confirmed that posterior malleolus fractures
are a heterogeneous group of injuries in terms of their mechanism of injury, morphology, and association with injuries to the medial or lateral structures. We noted that no uniformity was present in the diagnosis or treatment of these injuries. The cutoff size used for determining the treatment varied and was not based on any of the evidence presented in the biomechanical studies. We noted that
Table 3 Studies identifying development of arthrosis Investigator
Patients Developing Ankle Arthritis
Grade/Patients (n)
Patients Treated Conservatively
Patients Treated Operatively
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
36 (35.2) 9 (20); (6 25% [13.3]; 3 25% [6.6]) >31 (>50) 32 (62.7)
0/0; 1/31; 2/5; 3/0 NR
Mean score 0* NR
Mean score 1* NR
NR Normal/19; minimal/20; moderate/7; marked/5
NR; incidence higher in this group 17, 16, 6, 5 (of these 44 patients, 28 with trimalleolar fractures were treated with closed method [i.e., no fixation of medial/lateral malleolus and 16 had fixation of medial/lateral malleolus but no fixation of posterior malleolus fracture]) Mean score 1.2* NR 17, 3, 3, 0 0, 6, 0, 4, 1
NR; incidence lower in this group 2, 4, 1, 0 (7 of a total of 51 patients underwent surgical fixation of posterior malleolus)
NR NR NR
NR NR NR
0
1
Jaskulka et al (7) (n ¼ 62) McDaniel and Wilson (5) (n ¼ 51)
de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper et al (21) (n ¼ 38) Bauer et al (43) (n ¼ 33) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR) Heim (39) (n ¼ 60)
Tejwani et al (8) (n ¼ 54)
Mean score, 1.2 NR 11 (28.9) 26 (78.6) (6 lost to follow-up) 41 (47.6) NR 28 (46.6)
1 Patient from surgically fixed group
0, 1, 2, 3/NA for all NR 0/27; 1/6; 2/4; 3/1 0/1; 1/12; 2/4; 3/7; 4/3 0/45; 1/36; 2/3; 3/2 NR Normal, 17; osteophytes, 19; benign arthrosis, 5; severe arthrosis, 4 NR
Abbreviations: NA, not available; NR, not reported. Data presented as n (%). The grade of osteoarthritis was included if recorded; however, significant heterogeneity was noted. * Statistically nonsignificant.
Mean score 1* NR 10, 3, 1, 1 1, 6, 4, 3, 2
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several outcome measures were used to determine the outcome and these were not uniformly reported; hence, a statistical analysis could not be performed. Also, the published data were neither uniform nor consistent in the quality and methodology of the studies (3,9). Does Size Matter? The evidence available regarding identifying the role of the posterior malleolus size as a prognostic indicator is weak, which was reflected by the poor stratification of these fractures. For isolated posterior malleolar fractures, 2 studies reported good outcomes for most of the patients when treated conservatively, irrespective of the size of the fragment (20–31). In combined injuries, we identified that conservative treatment was a default choice when the fragment size was small; however, this was not based on strong evidence. de Vries et al (37) observed that a fracture dislocation was associated with a larger posterior malleolus size and poorer outcome, which indirectly related the size to injury severity and poor outcome. Most of the studies reported no association between the posterior malleolus fragment size and the long-term outcome, with either conservative or surgical treatment. The study by Mingo-Robinet et al (36) is 1 exception; they found better outcomes if the fracture size was 25% of the distal articular surface and not affected by the quality of reduction. McDaniel and Wilson (5) reported an increased incidence of residual talar subluxation with more fair or poorer results when the fragment size was 25% if conservatively managed. They concluded that anatomic reduction of the posterior malleolus fragment is necessary for larger fractures (25%) and that failure to achieve a good reduction and correction of subluxation of the posterior malleolus fragment measuring 25% will not affect the overall outcome (5). The biomechanical studies and some clinical studies have established that isolated posterior malleolar fractures are inherently stable and become unstable with sequential injuries of the medial and lateral columns. Even when these columns are reconstructed, anatomic models have demonstrated increased point loading or stress on the anteromedial joint surface, which might induce arthritic changes. From our assessment of the clinical and biomechanical studies, we identified the following 3 factors that will prognosticate these injuries: 1. Presence of fracture dislocation at injury 2. Articular surface congruity 3. Residual talar subluxation The present review has confirmed that presence of a posterior malleolus fracture in the setting of fracture dislocation indicates significant energy was imparted at the injury, with a relatively large posterior malleolar fragment, and was associated with increased comminution (43). Thus, indirect evidence has shown that large fragments should be surgically fixed; however, the cutoff for the fragment size has been variably reported in published studies. Similarly, intraoperatively, once the medial and lateral structures have been anatomically fixed, the posterior malleolus fragment should be reduced using ligamentotaxis, provided the posterior inferior tibiofibular ligament is intact. In the presence of articular incongruity, several investigators have recommended fixation of the posterior malleolus fractures with a size of 10% of the distal tibial articular surface (4,7,38). In terms of the fixation methods, direct reduction and internal fixation using a posterolateral approach with screw or plate osteosynthesis seems to provide better outcomes (35,44). Overall, it is difficult to reach a consensus, because the published data are fragmented in terms of the method and reporting of results,
with no standardized outcomes measures used. The short-term period of some studies meant that primary outcomes such as osteoarthritis could not be fully assessed. The lack of a strict definition and grading of ankle arthritis also made it difficult to assess the numbers requiring future joint salvage surgery. We would advocate a longitudinal study or registry with accurate computed tomography analysis of the fracture site, size, and shape to assess the full implications of these fractures and to record the prognostic markers of reduction such as articular surface congruity, residual talar subluxation, and the presence of fracture dislocation at the injury (9). In conclusion, the present review has highlighted the finding that posterior malleolus fractures involving the combined medial and lateral column have a poor prognosis compared with bimalleolar injuries. The diagnostic test should be a computed tomography scan to allow for accurate planning of the fixation. Uncertainty still exists regarding the true prognostic value of the fracture size, reflecting the lack of standardized studies with long-term follow-up data to exclude primary endpoints such as osteoarthritis. When a posterior malleolus fracture is associated with fracture dislocation of the ankle, the surgeon should have a low threshold for surgical fixation. This should be confirmed intraoperatively after assessing residual talar subluxation and joint congruity. References 1. Court-Brown M, McBirnie J, Wilson G. Adult ankle fracturesdan increasing problem? Acta Ortho Scand 69:43–47, 1998. 2. Xu HL, Li X, Zhang DY, Fu ZG, Wang TB, Zhang PX, Jiang BG, Shen HL, Wang G, Wang GL, Wu XB. A retrospective study of the posterior malleolar fractures. Int Orthop 36:1929–1936, 2012. 3. Van den Bekerom MPJ, Haverkamp D, Kloen P. Biomechanical and clinical evaluation of posterior malleolar fractures: a systematic review of the literature. J Trauma 66:279–284, 2009. 4. Lindsjo U. Operative treatment of ankle fracture dislocations: a follow-up study of 306/321 consecutive cases. Clin Orthop Relat Res 199:28–38, 1985. 5. McDaniel WJ, Wilson FC. Trimalleolar fractures of the ankle: an end result study. Clin Orthop Relat Res 122:37–45, 1977. 6. Broos PL, Bisschop AP. Operative treatment of ankle fractures in adults: correlation between types of fractures and final results. Injury 22:403–406, 1991. 7. Jaskulka RA, Ittner G, Schedl R. Fractures of the posterior tibial margin: their role in the prognosis of malleolar fractures. J Trauma 29:1565–1570, 1989. 8. Tejwani NC, Pahk B, Egol KA. Effect of posterior malleolar fracture on outcome after unstable ankle fracture. J Trauma 69:666–669, 2010. 9. Irwin TA, Lien J, Kadakia AR. Posterior malleolus fractures. J Am Acad Orthop Surg 21:32–40, 2013. 10. Rudolff MI. Fractures of the lower extremity. In: Campbell’s Operative Orthopaedics, pp. 2628–2629, edited by ST Canale, JH Beaty, Elsevier, New York, 2013. 11. Davidovitch RI, Egol KA. Ankle fractures. In: Rockwood and Green’s Fractures in Adults, pp. 1975–2012, edited by RW Bucholz, CM Court-Brown, JD Heckman, PTornetta III, Wolters Kluwer/Lippincott Williams & Wilkins, New York, 2010. 12. Wessel J. The reliability and validity of pain threshold measurements in osteoarthritis of the knee. Scand J Rheumatol 24:238–242, 1995. n A, Kowalski J, 13. Lundeberg T, Lund I, Dahlin L, Borg E, Gustafsson C, Sandin L, Rose Eriksson SV. Reliability and responsiveness of three different pain assessments. J Rehabil Med 33:279–283, 2001. 14. Bijur PE, Silver W, Gallagher EJ. Reliability of the visual analog scale for measurement of acute pain. Acad Emerg Med 8:1153–1157, 2001. 15. Olerud C, Molander H. A scoring scale for symptom evaluation after ankle fracture. Arch Orthop Trauma Surg 103:190–194, 1984. 16. Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 15:349–353, 1994. 17. Ibrahim T, Beiri A, Azzabi M, Best AJ, Taylor GJ, Menon DK. Reliability and validity of the subjective component of the American Orthopaedic Foot and Ankle Society clinical rating scales. J Foot Ankle Surg 46:65–74, 2007. 18. Cedell CA. Supination-outward rotation injuries of the ankle: a clinical and roentgenological study with special reference to the operative treatment. Acta Orthop Scand Suppl 110:3, 1967. 19. Scheidt KB, Stiehl JB, Skrade DA, Barnhardt T. Posterior malleolar ankle fractures: an in vitro biomechanical analysis of stability in the loaded and unloaded states. J Ortho Trauma 6:96–101, 1992. 20. Raasch WG, Larkin J, Draganich LF. Assessment of the posterior malleolus as a restraint to posterior subluxation of the ankle. J Bone Joint Surg Am 74:1201–1206, 1992.
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21. Harper MC. Talar shift: the stabilizing role of the medial, lateral and posterior ankle structures. Clin Orthop Relat Res 257:177–183, 1990. 22. Harper MC. Posterior instability of the talus: an anatomic evaluation. Foot Ankle 10:36–39, 1989. 23. Harper MC, Hardin G. Posterior malleolar fractures of the ankle associated with external rotation abduction injuries: results with and without internal fixation. J Bone Joint Surg Am 70:1348–1356, 1988. 24. Papachristou G, Efstathopoulos N, Levidiotis C, Chronopoulos E. Early weight bearing after posterior malleolar fractures: an experimental and prospective clinical study. J Foot Ankle Surg 42:99–104, 2003. 25. Macko VW, Matthews LS, Zwirkoski P, Goldstein SA. The joint-contact area of the ankle: the contribution of the posterior malleolus. J Bone Joint Surg Am 73:347–351, 1991. 26. Hartford JM, Gorczyca JT, McNamara JL, Mayor MB. Tibiotalar contact area contribution of posterior malleolus and deltoid ligament. Clin Orthop Relat Res 320:182–187, 1995. 27. Vrahas M, Fu F, Veenis B. Intraarticular contact stresses with simulated ankle malunions. J Orthop Trauma 8:159–166, 1994. 28. Fitzpatrick DC, Otto JK, McKinley TO, Marsh JL, Brown TD. Kinematic and contact stress analysis of posterior malleolus fractures of the ankle. J Orthop Trauma 18:271–278, 2004. 29. Donken CCMA, Goorden AJF, Verhofstad MHJ, Edwards MJ, van Laarhoven CJHM. The outcome at 20 years of conservatively treated “isolated” posterior malleolar fractures of the ankle. J Bone Joint Surg Br 93-B:1621–1625, 2011. 30. Neumaier Probst E, Maas R, Meenen NM. Isolated fracture of the posterolateral tibial lip (Volkmann’s triangle). Acta Radiol 38:359–362, 1997. 31. Nugent JF, Gale BD. Isolated posterior malleolar ankle fractures. J Foot Surg 29:80– 83, 1990. 32. Switaj PJ, Weatherford B, Fuchs D, Rosenthal B, Pang E, Kadakia AR. Evaluation of posterior malleolar fractures and the posterior pilon variant in operatively treated ankle fractures. Foot Ankle Int 35:886–895, 2014.
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33. Haraguchi N, Haruyama H, Toga H, Kato M. Pathoanatomy of the posterior malleolar fracture of the ankle. J Bone Joint Surg Am 88-A:1085–1092, 2006. 34. Weber M. Trimalleolar fractures with impaction of the posteromedial tibial plafond: implications for talar stability. Foot Ankle Int 25:716–727, 2004. 35. Gardner MJ, Streubel PN, McCormick JJ, Klien SE, Johnson JE, Ricci WM. Surgeon practices regarding operative treatment of posterior malleolus fractures. Foot Ankle Int 32:385–393, 2011. 36. Mingo-Robinet J, Lopez-Duran L, Galeote JE, Martinez-Cervell C. Ankle fractures with posterior malleolar fragment: management and results. J Foot Ankle Surg 50:141–145, 2011. 37. de Vries JS, Wijgman AJ, Sierevelt IN, Schaap GR. Long-term results of ankle fractures with a posterior malleolar fragment. J Foot Ankle Surg 44:211–217, 2005. 38. Langenhuijsen JF, Heetveld MJ, Ultee JM, Steller EP, Butzelaar RMJM. Results of ankle fractures with involvement of the posterior tibial margin. J Trauma 53:55–60, 2002. 39. Heim UF. Trimalleolar fractures: late results after fixation of the posterior fragment. Orthopedics 12:1053–1059, 1989. 40. Miller AN, Carroll EA, Parker RJ, Helfet DL, Lorich DG. Posterior malleolar stabilization of syndesmotic injuries is equivalent to screw fixation. Clin Orthop Relat Res 468:1129–1135, 2010. 41. De Souza LJ, Gustilo RB, Meyer T. Results of operative treatment of displaced external rotation-abduction fractures of the ankle. J Bone Joint Surg Am 67-A: 1066–1074, 1985. 42. Olerud C, Molander H. Bi and trimalleolar ankle fractures operated with nonrigid internal fixation. Clin Orthop Relat Res 206:253–260, 1986. 43. Bauer M, Bergstrom B, Hemborg A, Sandegard J. Malleolar fractures: non-operative versus operative treatment: a controlled study. Clin Orthop Relat Res 199:17–27, 1985. 44. Abdelgawad AA, Kadous A, Kanlic E. Posterolateral approach for treatment of posterior malleolus fracture of the ankle. J Foot Ankle Surg 50:607–611, 2011.
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Review
Management of Posterior Malleolar Fractures: A Systematic Review Saurabh Odak, MBBS, MRCS 1, Raju Ahluwalia, MB ChB, FRCS 2, Puthanveettil Unnikrishnan, MBBS, MRCS 1, Michael Hennessy, BSc, MB ChB, FRCS 3, Simon Platt, MB ChB, FRCS 3 1 2 3
Specialist Trainee, Trauma and Orthopaedics, Warrington Hospital, Cheshire, United Kingdom Consultant Orthopaedic Surgeon, Kings College London, London, United Kingdom Consultant Orthopaedic Surgeon, Arrowe Park Hospital, Wirral, United Kingdom
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 3
Posterior malleolar fractures are relatively common and usually result from rotational ankle injuries. Although treatment of associated lateral and medial structures is well established, several controversies exist in the management of posterior malleolus fractures. We performed a systematic review of the current published data with regard to the diagnosis, management, and prognosis of posterior malleolus fractures. A total of 33 studies (8 biomechanical and 25 clinical) with >950 patients were reviewed. The outcome of ankle fractures with posterior malleolar involvement was poor; however, the evidence was not enough to prove that the size of the posterior malleolus affects the outcome. Significant heterogeneity was noted in the cutoff size of the posterior malleolar fragment in determining management. The outcome was related to other factors, such as fracture displacement, congruency of the articular surface, and residual tibiotalar subluxation. Indirect evidence showed that large fracture fragments were associated with fracture dislocations and ankle instability and, thus, might require surgical fixation. We have concluded that the evidence to prove that the size of the posterior malleolar affects the outcome of ankle fractures is not enough, and the decision to treat these fractures should be determined by other factors, as stated previously. Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: ankle fractures outcome talus tibia trimalleolar fracture Volkmann’s fracture
Ankle fractures account for about 4% of all body fractures, with an annual incidence of 124 per 10,000 persons in the United Kingdom (1,2). More than one third of these fractures will involve the posterior malleolus with several variants described in published studies (1). The current published data suggest a poor outcome for ankle fractures involving the posterior malleolus (3–9). Although the management of associated medial and lateral structures is well established, the management of the posterior malleolus fractures remains controversial. Currently, no clear consensus has been reached regarding the indications of the operative and nonoperative management of these fractures with the decision often determined by the size of the fragment. We performed a systematic review of the English-language published data to assess the outcome of ankle fractures treated operatively and nonoperatively and involving the posterior malleolus. We
Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Saurabh Odak, MBBS, MRCS, Trauma and Orthopaedics, Warrington Hospital, 2 Ward Close, Great Sankey, Warrington, Cheshire WA5 8XY, UK. E-mail address: [email protected] (S. Odak).
also assessed the factors affecting the outcome, including the fragment size, which could guide the treating surgeon in the management of these injuries.
Materials and Methods The review incorporated an electronic search of the MedlineÒ database using PubMedÒ as the search engine (U.S. National Institutes of Health, National Library of Medicine) and EmbaseÒ (Elsevier BV, Amsterdam, The Netherlands), the Cochrane Library (John Wiley & Sons, West Sussex, UK), ProQuestÒ (ProQuest, Ann Arbor, MI). We included all the studies published from January 1966 to July 2014. We used the following search terms: posterior malleolar fractures, trimalleolar fractures, and Volkmann’s fractures. In addition, the appropriate MeSH terms of assessment, diagnosis, evaluation, prognosis, outcomes, management, and treatment were entered and Boolean operators used. We limited our search to studies published in the English language only. Three of us (S.O., R.A., P.U.) independently evaluated the abstracts for scientific content and quality. Our inclusion criteria were any clinical and/or biomechanical studies that included posterior malleolus fractures and the evaluation, diagnosis, management, and prognosis. Once the abstract was found suitable, the study was retrieved and thoroughly evaluated. The references in the retrieved studies were manually checked to find additional relevant publications. Finally, the published proceedings of recent scientific meetings and conferences were followed, along with a manual search of current orthopedic textbooks (10,11). We excluded studies in which posterior malleolus fractures were associated
1067-2516/$ - see front matter Ó 2016 by the American College of Foot and Ankle Surgeons. All rights reserved. http://dx.doi.org/10.1053/j.jfas.2015.04.001
S. Odak et al. / The Journal of Foot & Ankle Surgery 55 (2016) 140–145
with tibial shaft fractures, distal tibial metaphyseal fractures (pilon fractures), stress fractures, open and pathologic fractures, and case reports, technical notes, and tips. Data Extraction The data extracted included the demographic details of the patients, diagnosis, and treatment, including nonoperative and operative treatment. When assessing these patients, we included all the methods of nonoperative and operative treatment, irrespective of the method of treatment and fixation and the approach used. We included all the outcome measures described in the present study, including ankle osteoarthritis and objective measures such as the visual analog scale for pain (12–14), the Olerud and Mollander scores (15), the American Orthopedic Foot and Ankle Society scores (16,17), and Cedell’s scores, when available (18). Finally, we addressed the prognostic implications of posterior malleolus size in the final outcome of these injuries. Data were collected on a Microsoft OfficeÒ Excel spreadsheet, edition 2013 (Microsoft, Redmond, WA).
Results The initial search identified a total of 158 relevant citations; however, further scrutiny led to the exclusion of 125 studies (79.1%). Thus, 33 studies met the inclusion criteria, of which 8 (25.2%) were biomechanical and 25 (75.7%) were clinical studies. All the studies assessed were case series, and no randomized trials were identified during the analysis.
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Fitzpatrick et al (28) noted that with posterior malleolus fractures involving 50% of the articular surface, the contact stress redistributed to a more anterior and medial portion of the ankle joint. The investigators concluded that the peak stress redistribution with large posterior malleolus fractures led to abnormal loading of the tibiotalar joint and thus could lead to the development of post-traumatic ankle arthrosis (28). However, no conclusion was derived to explain why the abnormal load redistribution ensued even after adequate fracture fixation. Summary of Biomechanical Studies The results of the biomechanical studies have confirmed that posterior ankle stability is predominantly provided by anterior inferior tibiofibular ligament, posterior inferior tibiofibular ligament, and medial and lateral structures with little contribution from posterior malleolus. Although in itself the posterior malleolus might not be involved in significant load bearing at the tibiotalar joint, with posterior malleolus fractures, the redistribution of the load is abnormal, which might predispose the patient to the development of posttraumatic arthritis. Clinical Studies
Biomechanical Studies A total of 8 studies (25.2%) were identified that assessed the role of the posterior malleolus in ankle stability and joint loading. A synopsis of these studies follows. Scheidt et al (19) showed that a posterior malleolus fracture measuring 25% of the distal tibial articular surface led to posterior translation of the talus with an axial loads of 15 kg (150 N), and fixation of these fractures reduced posterior instability, provided the posterior inferior tibiofibular ligament was intact. However, the findings of the present study were contradicted by Raasch et al (20), who demonstrated that osteotomizing 40% of the posterolateral tibial margin did not significantly increase the posterior translation of the talus by a posteriorly directed force of 200 N, as long as the anterior inferior tibiofibular ligament and lateral malleolus were intact (20). This was further confirmed by Harper (21), who did not find a significant posterior talar translation with a posterior malleolus fracture measuring 50% of the distal tibial articular surface. However, in the setting of a combined disruption of the lateral and medial ligamentous structures, significant posterior translation of the talus occurred (21–23). Papachristou et al (24), using photoelastic bone models, showed that during axial loading of the distal tibial articular surface, the load was concentrated only in the middle 50% and not in the posterior 25% of the articular surface. They thus concluded that the posterior malleolus might not be involved in load bearing. Macko et al (25) noted decreased joint contact area as the size of the posterior malleolus fracture increased to >33% of the distal tibial surface with the ankle in neutral or 10 of dorsiflexion. They concluded that this increase in focal load concentration at the tibiotalar joint might predispose to early post-traumatic degenerative changes. Hartford et al (26) agreed with these findings, reporting that an increasing posterior malleolus fracture size decreased the tibiotalar contact area, which was not affected by the integrity of the deltoid ligament. Both studies support the concept that an increasing posterior malleolus fracture size diminished the tibiotalar joint contact area (25,26). In contrast, Vrahas et al (27) noted that even after removing 40% of the posterior malleolus, the peak contact stress did not change. They thus hypothesized that even with a posterior malleolar malunion stress would not increase beyond the physiologic limits and might not contribute to the development of post-traumatic arthrosis (27).
A total of 960 patients from 25 studies with posterior malleolar fractures were included in the present review. Of the 960 patients, 288 were female and 219 were male patients from 16 studies; however, 9 studies with 453 patients did not report the gender distribution. The mean age was 45.48 (range 13 to 84) years. In most of the studies, the diagnosis and size of the posterior malleolus fracture was made from the lateral radiograph of the ankle. In 915 patients, the posterior malleolus was a part of combined injuries (i.e., anterior, medial, lateral, and/or syndesmotic structures), and in 45 patients, it was isolated (29–31). Diagnosis and Classification of Posterior Malleolus Fractures Standard anteroposterior and lateral ankle radiographs were used in the diagnosis of these injuries in most of the studies. However, the reliability of using lateral radiographs in accurately determining the size of the posterior malleolus fragment has been questioned (25,32). Haraguchi et al (33) classified posterior malleolus fractures using computed tomography into 3 types: 1. Posterolateral oblique type (67%) 2. Medial extension type (19%) 3. Small shell type (14%)
Variants of Posterior Malleolar Fracture Two studies (17 patients) described a separate variant of the posterior malleolus fracture that involved the posteromedial distal tibial articular surface (34,35), along with medial and/or lateral injuries. All these variant fractures underwent open reduction and internal fixation using either a posterolateral or a posteromedial approach, and the investigators reported satisfactory outcomes. A recent study by Switaj et al (32) reported a 20% incidence of posterior malleolus variant (termed the “posterior pilon variant”) in operatively treated ankle fractures. Isolated Posterior Malleolus Fractures Three separate studies involving 45 patients assessed isolated posterior malleolus fractures (29–31). All the fractures were managed conservatively, and all the studies had a relatively long follow-up period. The fragment size ranged from 3% to 47% of the distal tibial
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articular surface. Only 1 patient developed severe (grade 2) ankle arthrosis, and only 2 patients complained of severe ankle pain. One study reported excellent or good Olerud and Mollander scores, Cedell’s score, and ankle range of motion scores in most patients (18 of 23 patients, 78.2%). The investigators thus advocated conservative treatment of isolated posterior malleolar fractures (29–31). Combined Ankle Injuries That Included Posterior Malleolus Fractures We examined the results of both operative and nonoperative management strategies to determine their benefit in the treatment of posterior malleolus fracture. Nonoperative Treatment. In all, 419 patients (45.8%) from 13 studies (Table 1) had ankle fractures in which the posterior malleolus fracture was treated nonoperatively in conjunction with surgically treated medial or lateral fractures (2,4–8,23,36–42). In 2 studies, the number of patients treated nonoperatively was not specified (4,42). The size of the posterior malleolus fragment varied from 5% to 55% of the distal tibial articular surface in this group. Significant heterogeneity was noted regarding the cutoff size of the posterior malleolus fragment chosen for conservative management. In general, smaller posterior malleolus fractures were treated nonoperatively (2,4–8,23,36–38,43). Only a few studies reported the outcomes of nonoperative treatment of posterior malleolus fractures solely according to the size of the fragment. However, the size of the posterior malleolus fragment in these studies ranged from 4% to 39% (2,8,23). The overall prognosis for conservatively treated trimalleolar ankle fractures was poorer than that of conservatively treated bimalleolar fractures. The incidence of post-traumatic arthritis was reported to be 29.8% in the nonoperatively treated group (7,38). No association was found between the size of the posterior malleolus fragment and the incidence of post-traumatic arthritis. Operative Treatment. A total of 16 studies with 452 patients (Table 2) reported on operative treatment (2,4–8,23,33,36–44). In 2 studies, the number of patients treated surgically was not specified (4,42). In
the studies that included a nonoperative and operative arm, the large posterior malleolus fragments were surgically fixed. The cutoff size of the posterior malleolus fragment fixed surgically ranged from 10% to 25% of the distal articular surface. Several methods of fixation and surgical approaches were described; however, anteroposterior screw fixation was the most common method of fixation (2,4,35). Posteroanterior plate osteosynthesis with a posterolateral approach for larger or comminuted fragments was also described, with several investigators reporting good results (35,36,40). The incidence of post-traumatic arthritis was reported to be 40% in this group. Just as with the previous group of patients, we did not find any association between the size of the posterior malleolar fragment and the incidence of post-traumatic arthritis. However, the outcomes were associated with congruity of the joint surface and stability of the ankle joint after fixation (2,5,38). Incidence of Osteoarthritis The analysis confirmed a high overall rate of clinical and/or radiologic osteoarthritis after these injuries (33.5%). Although the incidence of post-traumatic arthritis was greater in the surgical group (Table 3), we believe that that was not a true representation. This was because of the small number of patients and multiple confounding factors such as the choice of intervention, inconclusive classification, nonstandardized outcome measures, and many studies only reporting short-term follow-up periods. The factors associated with a greater incidence of post-traumatic osteoarthritis were fracture dislocations on initial presentation, congruency of the distal tibial articular surface, and residual talar subluxation after the treatment. The size of the posterior malleolus fragment was not associated with the incidence of post-traumatic osteoarthritis in the 2 groups. Discussion Although numerous studies have confirmed a poor prognosis for ankle fractures involving the posterior malleolus, controversies still exist regarding the appropriate management and indications for
Table 1 Studies in which posterior malleolus fractures were treated nonoperatively (13 studies were identified, with a total of 419 ankle fractures) Investigator
Patients With PM Fractures Treated Nonoperatively
Average PM Fragment Size in Whole Group (%)
Average PM Fragment Size Treated Conservatively (%)
Conservative Treatment Used
Weightbearing Status
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
60 (58.8) 27 (60)
NR NR
12.5 4.9 NR
NR Cast immobilization (3 to 4 wk)
Jaskulka et al (7) (n ¼ 62) McDaniel and Wilson (5) (n ¼ 51)
48 (77.4) 44 (86.2)
NR NR
NR NR
de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper (21) (n ¼ 38) Bauer et al (43) (n ¼ 33)
34 43 23 10
19.4 (3 to 49) NR 30.34 (25 to 45) NR
NR NR 28.52 (25 to 39) NR
Broos and Bisschop (6) (n ¼ 178)
78 (43.8)
NR
de Souza et al (41) (n ¼ 46)
14 (30.4)
NR
NR; however, all fractures were 33 NR
Below-the-knee cast for mean of 10 wk Above-the-knee cast for mean of 8 wk; total of 11 wk in cast NR NR Cast or splint for mean of 8 wk Percutaneous hook test to assess stability under anesthesia; closed reduction and cast for 6 wk NR
NR Non-weightbearing for 8 (range 4 to 12) wk 3 wk NR
Tejwani et al (8) (n ¼ 54) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR)
34 (62.9) NR NR
NR NR NR
16.1 (4 to 28) NR NR
(75.5) (75.4) (60.5) (30.3)
Abbreviations: NR, not reported; PM, posterior malleolar. Data presented as n (%), % (range), or mean standard deviation, unless otherwise noted. Nonoperative treatment consisted of cast immobilization for 4 to 11 weeks.
Short cast for 8 wk
NR Below-the-knee cast for 6 wk Below-the-knee walking cast of Sarmiento type for 6 wk
NR NR NR 6 wk
NR Non-weightbearing 2 wk; partial weightbearing 2 wk; full weightbearing 4 wk 6 wk 6 wk Immediate post-ankle fixation
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Table 2 Results of 16 studies (n ¼ 452 patients) in which operative intervention was undertaken Investigator
Patients With PM Fractures Treated Operatively
Average PM Fragment Size Treated Operatively (%)
Fixation Type
Approach
Anteroposterior, 19; posteroanterior, 23 Cortical screws, 4; partially threaded cannulated screws, 11 Anteromedial screw fixation
NR Anteroposterior, 15; posterolateral, 3
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
42 (41.1) 18 (40)
28.5 9.2 NR
Jaskulka et al (7) (n ¼ 62)
14 (22.5)
NR
McDaniel and Wilson (5) (n ¼ 51) de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper et al (21) (n ¼ 38) Bauer et al (43) (n ¼ 33) Broos and Bisschop (6) (n ¼ 178) de Souza et al (41) (n ¼ 46) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR) Abdelgawad et al (44) (n ¼ 12)
7 11 14 15 23 100 14 NR NR 12
(13.7) (24.4) (24.5) (39.4) (69.6) (56.1) (30.4)
(100)
All 25 NR NR 31.33 NR NR NR NR NR All 30
Papachristou et al (24) (n ¼ 15) Haraguchi et al (33) (n ¼ 57)
15 (100) 57 (100)
Miller et al (40) (n ¼ 18) Tejwani et al (8) (n ¼ 54)
18 (100) 20 (37)
25 to 33 Posterolateral oblique type, 11.7; medial extension type, 29.7 NR 25.2 (16 to 38.1)
Heim (39) (n ¼ 60)
60 (100)
NR
Screw fixation NR NR Screw fixation, 14; Steinmann, 1 NR Screw fixation Screw fixation, 11; wiring of PM, 1 NR NR Primary open reduction internal fixation, 10; revision fixation, 2 Open reduction internal fixation Open reduction internal fixation
Open reduction internal fixation Indirect reduction, anteroposterior screw fixation (n ¼ 10); open reduction, direct internal fixation (n ¼ 10) NR
Anteromedial and extension of medial malleolar incision Anteroposterior NR NR NR NR NR Front to back NR NR Posterolateral Posterolateral; posteromedial NR
Posterolateral Posterolateral (n ¼ 10)
NR
Abbreviations: NR, not reported; PM, posterior malleolar. Data presented as n (%), % (range), or mean standard deviation, unless otherwise noted.
fixation in these fractures. Traditionally, the size of the posterior malleolus has been used as a guide for the management of these fractures. However, a recent study by Gardner et al (35) suggested that significant variations exist in the management of posterior malleolus fractures among clinicians, with various factors and size considered for surgical fixation. Our review has confirmed that posterior malleolus fractures
are a heterogeneous group of injuries in terms of their mechanism of injury, morphology, and association with injuries to the medial or lateral structures. We noted that no uniformity was present in the diagnosis or treatment of these injuries. The cutoff size used for determining the treatment varied and was not based on any of the evidence presented in the biomechanical studies. We noted that
Table 3 Studies identifying development of arthrosis Investigator
Patients Developing Ankle Arthritis
Grade/Patients (n)
Patients Treated Conservatively
Patients Treated Operatively
Xu et al (2) (n ¼ 102) Mingo-Robinet et al (36) (n ¼ 45)
36 (35.2) 9 (20); (6 25% [13.3]; 3 25% [6.6]) >31 (>50) 32 (62.7)
0/0; 1/31; 2/5; 3/0 NR
Mean score 0* NR
Mean score 1* NR
NR Normal/19; minimal/20; moderate/7; marked/5
NR; incidence higher in this group 17, 16, 6, 5 (of these 44 patients, 28 with trimalleolar fractures were treated with closed method [i.e., no fixation of medial/lateral malleolus and 16 had fixation of medial/lateral malleolus but no fixation of posterior malleolus fracture]) Mean score 1.2* NR 17, 3, 3, 0 0, 6, 0, 4, 1
NR; incidence lower in this group 2, 4, 1, 0 (7 of a total of 51 patients underwent surgical fixation of posterior malleolus)
NR NR NR
NR NR NR
0
1
Jaskulka et al (7) (n ¼ 62) McDaniel and Wilson (5) (n ¼ 51)
de Vries et al (37) (n ¼ 45) Langenhuijsen et al (38) (n ¼ 57) Harper et al (21) (n ¼ 38) Bauer et al (43) (n ¼ 33) Olerud and Molander (42) (n ¼ 86) Lindsjo (4) (NR) Heim (39) (n ¼ 60)
Tejwani et al (8) (n ¼ 54)
Mean score, 1.2 NR 11 (28.9) 26 (78.6) (6 lost to follow-up) 41 (47.6) NR 28 (46.6)
1 Patient from surgically fixed group
0, 1, 2, 3/NA for all NR 0/27; 1/6; 2/4; 3/1 0/1; 1/12; 2/4; 3/7; 4/3 0/45; 1/36; 2/3; 3/2 NR Normal, 17; osteophytes, 19; benign arthrosis, 5; severe arthrosis, 4 NR
Abbreviations: NA, not available; NR, not reported. Data presented as n (%). The grade of osteoarthritis was included if recorded; however, significant heterogeneity was noted. * Statistically nonsignificant.
Mean score 1* NR 10, 3, 1, 1 1, 6, 4, 3, 2
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several outcome measures were used to determine the outcome and these were not uniformly reported; hence, a statistical analysis could not be performed. Also, the published data were neither uniform nor consistent in the quality and methodology of the studies (3,9). Does Size Matter? The evidence available regarding identifying the role of the posterior malleolus size as a prognostic indicator is weak, which was reflected by the poor stratification of these fractures. For isolated posterior malleolar fractures, 2 studies reported good outcomes for most of the patients when treated conservatively, irrespective of the size of the fragment (20–31). In combined injuries, we identified that conservative treatment was a default choice when the fragment size was small; however, this was not based on strong evidence. de Vries et al (37) observed that a fracture dislocation was associated with a larger posterior malleolus size and poorer outcome, which indirectly related the size to injury severity and poor outcome. Most of the studies reported no association between the posterior malleolus fragment size and the long-term outcome, with either conservative or surgical treatment. The study by Mingo-Robinet et al (36) is 1 exception; they found better outcomes if the fracture size was 25% of the distal articular surface and not affected by the quality of reduction. McDaniel and Wilson (5) reported an increased incidence of residual talar subluxation with more fair or poorer results when the fragment size was 25% if conservatively managed. They concluded that anatomic reduction of the posterior malleolus fragment is necessary for larger fractures (25%) and that failure to achieve a good reduction and correction of subluxation of the posterior malleolus fragment measuring 25% will not affect the overall outcome (5). The biomechanical studies and some clinical studies have established that isolated posterior malleolar fractures are inherently stable and become unstable with sequential injuries of the medial and lateral columns. Even when these columns are reconstructed, anatomic models have demonstrated increased point loading or stress on the anteromedial joint surface, which might induce arthritic changes. From our assessment of the clinical and biomechanical studies, we identified the following 3 factors that will prognosticate these injuries: 1. Presence of fracture dislocation at injury 2. Articular surface congruity 3. Residual talar subluxation The present review has confirmed that presence of a posterior malleolus fracture in the setting of fracture dislocation indicates significant energy was imparted at the injury, with a relatively large posterior malleolar fragment, and was associated with increased comminution (43). Thus, indirect evidence has shown that large fragments should be surgically fixed; however, the cutoff for the fragment size has been variably reported in published studies. Similarly, intraoperatively, once the medial and lateral structures have been anatomically fixed, the posterior malleolus fragment should be reduced using ligamentotaxis, provided the posterior inferior tibiofibular ligament is intact. In the presence of articular incongruity, several investigators have recommended fixation of the posterior malleolus fractures with a size of 10% of the distal tibial articular surface (4,7,38). In terms of the fixation methods, direct reduction and internal fixation using a posterolateral approach with screw or plate osteosynthesis seems to provide better outcomes (35,44). Overall, it is difficult to reach a consensus, because the published data are fragmented in terms of the method and reporting of results,
with no standardized outcomes measures used. The short-term period of some studies meant that primary outcomes such as osteoarthritis could not be fully assessed. The lack of a strict definition and grading of ankle arthritis also made it difficult to assess the numbers requiring future joint salvage surgery. We would advocate a longitudinal study or registry with accurate computed tomography analysis of the fracture site, size, and shape to assess the full implications of these fractures and to record the prognostic markers of reduction such as articular surface congruity, residual talar subluxation, and the presence of fracture dislocation at the injury (9). In conclusion, the present review has highlighted the finding that posterior malleolus fractures involving the combined medial and lateral column have a poor prognosis compared with bimalleolar injuries. The diagnostic test should be a computed tomography scan to allow for accurate planning of the fixation. Uncertainty still exists regarding the true prognostic value of the fracture size, reflecting the lack of standardized studies with long-term follow-up data to exclude primary endpoints such as osteoarthritis. When a posterior malleolus fracture is associated with fracture dislocation of the ankle, the surgeon should have a low threshold for surgical fixation. This should be confirmed intraoperatively after assessing residual talar subluxation and joint congruity. References 1. Court-Brown M, McBirnie J, Wilson G. Adult ankle fracturesdan increasing problem? Acta Ortho Scand 69:43–47, 1998. 2. Xu HL, Li X, Zhang DY, Fu ZG, Wang TB, Zhang PX, Jiang BG, Shen HL, Wang G, Wang GL, Wu XB. A retrospective study of the posterior malleolar fractures. Int Orthop 36:1929–1936, 2012. 3. Van den Bekerom MPJ, Haverkamp D, Kloen P. Biomechanical and clinical evaluation of posterior malleolar fractures: a systematic review of the literature. J Trauma 66:279–284, 2009. 4. Lindsjo U. Operative treatment of ankle fracture dislocations: a follow-up study of 306/321 consecutive cases. Clin Orthop Relat Res 199:28–38, 1985. 5. McDaniel WJ, Wilson FC. Trimalleolar fractures of the ankle: an end result study. Clin Orthop Relat Res 122:37–45, 1977. 6. Broos PL, Bisschop AP. Operative treatment of ankle fractures in adults: correlation between types of fractures and final results. Injury 22:403–406, 1991. 7. Jaskulka RA, Ittner G, Schedl R. Fractures of the posterior tibial margin: their role in the prognosis of malleolar fractures. J Trauma 29:1565–1570, 1989. 8. Tejwani NC, Pahk B, Egol KA. Effect of posterior malleolar fracture on outcome after unstable ankle fracture. J Trauma 69:666–669, 2010. 9. Irwin TA, Lien J, Kadakia AR. Posterior malleolus fractures. J Am Acad Orthop Surg 21:32–40, 2013. 10. Rudolff MI. Fractures of the lower extremity. In: Campbell’s Operative Orthopaedics, pp. 2628–2629, edited by ST Canale, JH Beaty, Elsevier, New York, 2013. 11. Davidovitch RI, Egol KA. Ankle fractures. In: Rockwood and Green’s Fractures in Adults, pp. 1975–2012, edited by RW Bucholz, CM Court-Brown, JD Heckman, PTornetta III, Wolters Kluwer/Lippincott Williams & Wilkins, New York, 2010. 12. Wessel J. The reliability and validity of pain threshold measurements in osteoarthritis of the knee. Scand J Rheumatol 24:238–242, 1995. n A, Kowalski J, 13. Lundeberg T, Lund I, Dahlin L, Borg E, Gustafsson C, Sandin L, Rose Eriksson SV. Reliability and responsiveness of three different pain assessments. J Rehabil Med 33:279–283, 2001. 14. Bijur PE, Silver W, Gallagher EJ. Reliability of the visual analog scale for measurement of acute pain. Acad Emerg Med 8:1153–1157, 2001. 15. Olerud C, Molander H. A scoring scale for symptom evaluation after ankle fracture. Arch Orthop Trauma Surg 103:190–194, 1984. 16. Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 15:349–353, 1994. 17. Ibrahim T, Beiri A, Azzabi M, Best AJ, Taylor GJ, Menon DK. Reliability and validity of the subjective component of the American Orthopaedic Foot and Ankle Society clinical rating scales. J Foot Ankle Surg 46:65–74, 2007. 18. Cedell CA. Supination-outward rotation injuries of the ankle: a clinical and roentgenological study with special reference to the operative treatment. Acta Orthop Scand Suppl 110:3, 1967. 19. Scheidt KB, Stiehl JB, Skrade DA, Barnhardt T. Posterior malleolar ankle fractures: an in vitro biomechanical analysis of stability in the loaded and unloaded states. J Ortho Trauma 6:96–101, 1992. 20. Raasch WG, Larkin J, Draganich LF. Assessment of the posterior malleolus as a restraint to posterior subluxation of the ankle. J Bone Joint Surg Am 74:1201–1206, 1992.
S. Odak et al. / The Journal of Foot & Ankle Surgery 55 (2016) 140–145
21. Harper MC. Talar shift: the stabilizing role of the medial, lateral and posterior ankle structures. Clin Orthop Relat Res 257:177–183, 1990. 22. Harper MC. Posterior instability of the talus: an anatomic evaluation. Foot Ankle 10:36–39, 1989. 23. Harper MC, Hardin G. Posterior malleolar fractures of the ankle associated with external rotation abduction injuries: results with and without internal fixation. J Bone Joint Surg Am 70:1348–1356, 1988. 24. Papachristou G, Efstathopoulos N, Levidiotis C, Chronopoulos E. Early weight bearing after posterior malleolar fractures: an experimental and prospective clinical study. J Foot Ankle Surg 42:99–104, 2003. 25. Macko VW, Matthews LS, Zwirkoski P, Goldstein SA. The joint-contact area of the ankle: the contribution of the posterior malleolus. J Bone Joint Surg Am 73:347–351, 1991. 26. Hartford JM, Gorczyca JT, McNamara JL, Mayor MB. Tibiotalar contact area contribution of posterior malleolus and deltoid ligament. Clin Orthop Relat Res 320:182–187, 1995. 27. Vrahas M, Fu F, Veenis B. Intraarticular contact stresses with simulated ankle malunions. J Orthop Trauma 8:159–166, 1994. 28. Fitzpatrick DC, Otto JK, McKinley TO, Marsh JL, Brown TD. Kinematic and contact stress analysis of posterior malleolus fractures of the ankle. J Orthop Trauma 18:271–278, 2004. 29. Donken CCMA, Goorden AJF, Verhofstad MHJ, Edwards MJ, van Laarhoven CJHM. The outcome at 20 years of conservatively treated “isolated” posterior malleolar fractures of the ankle. J Bone Joint Surg Br 93-B:1621–1625, 2011. 30. Neumaier Probst E, Maas R, Meenen NM. Isolated fracture of the posterolateral tibial lip (Volkmann’s triangle). Acta Radiol 38:359–362, 1997. 31. Nugent JF, Gale BD. Isolated posterior malleolar ankle fractures. J Foot Surg 29:80– 83, 1990. 32. Switaj PJ, Weatherford B, Fuchs D, Rosenthal B, Pang E, Kadakia AR. Evaluation of posterior malleolar fractures and the posterior pilon variant in operatively treated ankle fractures. Foot Ankle Int 35:886–895, 2014.
145
33. Haraguchi N, Haruyama H, Toga H, Kato M. Pathoanatomy of the posterior malleolar fracture of the ankle. J Bone Joint Surg Am 88-A:1085–1092, 2006. 34. Weber M. Trimalleolar fractures with impaction of the posteromedial tibial plafond: implications for talar stability. Foot Ankle Int 25:716–727, 2004. 35. Gardner MJ, Streubel PN, McCormick JJ, Klien SE, Johnson JE, Ricci WM. Surgeon practices regarding operative treatment of posterior malleolus fractures. Foot Ankle Int 32:385–393, 2011. 36. Mingo-Robinet J, Lopez-Duran L, Galeote JE, Martinez-Cervell C. Ankle fractures with posterior malleolar fragment: management and results. J Foot Ankle Surg 50:141–145, 2011. 37. de Vries JS, Wijgman AJ, Sierevelt IN, Schaap GR. Long-term results of ankle fractures with a posterior malleolar fragment. J Foot Ankle Surg 44:211–217, 2005. 38. Langenhuijsen JF, Heetveld MJ, Ultee JM, Steller EP, Butzelaar RMJM. Results of ankle fractures with involvement of the posterior tibial margin. J Trauma 53:55–60, 2002. 39. Heim UF. Trimalleolar fractures: late results after fixation of the posterior fragment. Orthopedics 12:1053–1059, 1989. 40. Miller AN, Carroll EA, Parker RJ, Helfet DL, Lorich DG. Posterior malleolar stabilization of syndesmotic injuries is equivalent to screw fixation. Clin Orthop Relat Res 468:1129–1135, 2010. 41. De Souza LJ, Gustilo RB, Meyer T. Results of operative treatment of displaced external rotation-abduction fractures of the ankle. J Bone Joint Surg Am 67-A: 1066–1074, 1985. 42. Olerud C, Molander H. Bi and trimalleolar ankle fractures operated with nonrigid internal fixation. Clin Orthop Relat Res 206:253–260, 1986. 43. Bauer M, Bergstrom B, Hemborg A, Sandegard J. Malleolar fractures: non-operative versus operative treatment: a controlled study. Clin Orthop Relat Res 199:17–27, 1985. 44. Abdelgawad AA, Kadous A, Kanlic E. Posterolateral approach for treatment of posterior malleolus fracture of the ankle. J Foot Ankle Surg 50:607–611, 2011.