Patients may present after an open reduction internal fixation (ORIF) with ongoing ankle pain. Cartilage defects are the most common cause in our practice. However, osteotomies, debridement, and fusions may benefit select patients.
Less favourable outcomes in patients over age of 65 years have been reported.1,2 Most of the complications are related to the quality of bone and wound healing. Depending on the health of the patient, these complications may require symptomatic treatment or dressings only, as further surgery is often inadvisable in older patients.
Patient Factors to Be Optimized in Treating Poor Outcomes
Poor control of diabetes 3 leads to poor outcomes. Prior to revision, infection as the cause needs to be ruled out and diabetic control should be optimized if further wound or bone healing issues are to be avoided.
Smokers have adverse outcomes associated with bone and wound healing complications. Cessation of smoking is desirable before embarking on revision surgery.
In open fractures, the infection rate following ORIF has been reported to be up to 40%.4 If infection is suspected clinically, then investigation by ESR, CRP, and joint aspiration is indicated. Complete debridement is required. In some cases, this may result in the need for fusion instead of reconstruction.
Some wound complications may require plastic surgical intervention with local or free flaps. The majority can be treated by dressings such as Iodosorb™ or acticoat™. Vacuum dressings may also be required. Higher AO fracture patterns were found to have greater rates of perioperative complications,5 including wound margin necrosis and prolonged hospital stay.
Patients with ongoing ankle pain not clearly localized to internal fixation, and in whom normal bony anatomy has been restored, will often have chondral injuries or impingement.6 CT scans can be used to assess fracture reduction, impingement, and osteochondral defects. MRI is often suboptimal with internal fixation in place. At the time of internal fixation removal, ankle arthroscopy can be used to diagnose any associated injury and treat intra-articular pathology. Documentation of the degree of cartilage injury is also useful in advising the patient and planning further intervention if symptoms persist.
Malreduction of the fibula with shortening of the lateral malleolus
Distal fibular displacement with associated tibiotalar subluxation leads to significantly increased tibiotalar contact pressures and subsequent short- and long-term complications.7 Fibular length can be assessed using the bimalleolar angle 8 and the talocrural angle. Other radiographic features of a normal distal fibular length include an intact Shenton’s line, equal joint space, and an intact curve between the lateral talus and the peroneal groove of the fibula.9 (Figure 1)
Figure 1. Radiographic features of shortened fibula
Several methods for fibular lengthening have been described, including transverse osteotomy at the level of the fracture site with autologous tibial graft with or without syndesmotic reduction and fixation.9,10 (Figure 2) Chao et al more recently described a fibular lengthening through a sagittal oblique osteotomy at the previous fracture level without the need for structural bone graft.11 In many of these patients, the fibula has a rotational and angular component in the malreduction that should be addressed at the time of the osteotomy. As a result, fibular osteotomy can be a challenging procedure.
Figure 2. Postoperative radiograph following fibular lengthening with syndesmotic fixation
Inadequate reduction of the syndesmosis
Reduction of the tibiofibular syndesmosis is a significant predictor of functional outcome in ankle injuries.12 However, standard radiographs do not reliably demonstrate the syndesmosis; CT scan is much more accurate.13 In surgery, direct visualization is preferable over intra-operative radiographic views and percutaneous reduction.14
In subacute disruptions, the normal anatomy is restored by repair of the ruptured ligament with placement of a syndesmotic screw. If adequate remnants of the AITFL are present, an anatomical surgical reconstruction of the anterior syndesmosis is possible.15 Chronic injuries can be treated by fusion of the distal tibiofibular syndesmosis or reconstruction.
All procedures should incorporate open debridement of the syndesmosis and, possibly, the medial clear space of the ankle. Fibular malunions should be addressed at the same time as a short or rotated fibula will not correctly reduce into the syndesmosis.
Inadequate reduction of the posterior malleolar segment
Symptomatic posterior malleolar fractures are generally larger than 25% of the joint surface.16 Posterolateral approach for fixation of the posterior malleolar segment gives good exposure; fixation with a buttress plate is stable and results in few local complications.17 Posterior malleolar malunion is often associated with lateral malleolus malunion and shortening. Therefore, correction of a malunion with a biplanar posterolateral subluxation of the talus cannot be obtained by osteotomy of the lateral malleolus alone.
Weber et al reported satisfactory outcome of corrective osteotomy of the posterior malleolus in four patients.18 All patients experienced improvement in pain. Mild to moderate residual symptoms were frequent and were attributed to the soft tissue and cartilage damage from the initial injury or weight-bearing on an incongruent joint.
Unrecognized fracture extension into the tibial plafond with ineffective fixation
Complex ankle fractures can have extensive bony involvement that can be missed on plain radiographs. Büchler et al recommended detailed assessment of all such injuries with computed tomography in order to better define the fracture pattern, as surgically relevant information is often missed.19
Medial malleolar fractures with vertical extension and some lateral malleolar fractures are associated with tibial impaction injuries. These may require osteotomy and bone grafting. However, there is a risk of avascular necrosis of the osteotomized fragment.
Despite careful technique and attention to detail, surgeons will inevitably encounter these complications. Ankle arthroscopy is invaluable in estimating the extent and degree of cartilage damage in borderline cases. In some cases, the ankle cannot be salvaged and ankle fusion may allow the fastest rehabilitation with the most reliable outcome.
- Srinivasan, C.M. and C.G. Moran, Internal fixation of ankle fractures in the very elderly. Injury, 2001. 32(7): p. 559-63.
- Salai, M., et al., The epidemic of ankle fractures in the elderly--is surgical treatment warranted? Arch Orthop Trauma Surg, 2000. 120(9): p. 511-3.
- Flynn, J.M., F. Rodriguez-del Rio, and P.A. Piza, Closed ankle fractures in the diabetic patient. Foot Ankle Int, 2000. 21(4): p. 311-9.
- Tho, K.S., P.L. Chiu, and S. Krishnamoorthy, Grade III open ankle fractures--a review of the outcome of treatment. Singapore Med J, 1994. 35(1): p. 57-8.
- Hoiness, P. and K. Stromsoe, Early complications of surgically managed ankle fractures related to the AO classification.A review of 118 ankle fractures treated with open reduction and internal fixation. Arch Orthop Trauma Surg, 1999. 119(5-6): p. 276-9.
- Boraiah, S., et al., Osteochondral lesions of talus associated with ankle fractures. Foot Ankle Int, 2009. 30(6): p. 481-5.
- Thordarson, D.B., et al., The effect of fibular malreduction on contact pressures in an ankle fracture malunion model. J Bone Joint Surg Am, 1997. 79(12): p. 1809-15.
- Rolfe, B., et al., Assessing fibular length using bimalleolar angular measurements. Foot Ankle, 1989. 10(2): p. 104-9.
- Weber, B.G. and L.A. Simpson, Corrective lengthening osteotomy of the fibula. Clin Orthop Relat Res, 1985(199): p. 61-7.
- Yablon, I.G. and R.E. Leach, Reconstruction of malunited fractures of the lateral malleolus. J Bone Joint Surg Am, 1989. 71(4): p. 521-7.
- Chao, K.H., et al., Corrective-elongation osteotomy without bone graft for old ankle fracture with residual diastasis. Foot Ankle Int, 2004. 25(3): p. 123-7.
- Weening, B. and M. Bhandari, Predictors of functional outcome following transsyndesmotic screw fixation of ankle fractures. J Orthop Trauma, 2005. 19(2): p. 102-8.
- Gardner, M.J., et al., Malreduction of the tibiofibular syndesmosis in ankle fractures. Foot Ankle Int, 2006. 27(10): p. 788-92.
- Miller, A.N., et al., Direct visualization for syndesmotic stabilization of ankle fractures. Foot Ankle Int, 2009. 30(5): p. 419-26.
- Beals, T.C. and A. Manoli, 2nd, Late syndesmosis reconstruction: a case report. Foot Ankle Int, 1998. 19(7): p. 485-8.
- De Vries, J.S., et al., Long-term results of ankle fractures with a posterior malleolar fragment. J Foot Ankle Surg, 2005. 44(3): p. 211-7.
- Forberger, J., et al., Posterolateral approach to the displaced posterior malleolus: functional outcome and local morbidity. Foot Ankle Int, 2009. 30(4): p. 309-14.
- Weber, M. and R. Ganz, Malunion following trimalleolar fracture with posterolateral subluxation of the talus--reconstruction including the posterior malleolus. Foot Ankle Int, 2003. 24(4): p. 338-44.
- Buchler, L., et al., Reliability of radiologic assessment of the fracture anatomy at the posterior tibial plafond in malleolar fractures. J Orthop Trauma, 2009. 23(3): p. 208-12.
Reprinted with permission from the Spring 2010 issue of COA Bulletin