SLR - December 2011 - Steve Czymbor
Reference: Hinterman, B., Barg, A, &. Knupp, M. (2011). Corrective supramalleolar osteotomy for malunited pronation-external rotation fractures of the ankle. The Journal of Bone and Joint Surgery, 93(B), 1367-1372.
Scientific Literature Review
Reviewed by: Steve Czymbor, DPM
Residency Program: Columbia St Mary’s Hospital, Milwaukee, WI
Podiatric Relevance:
Malunion or improper anatomical reduction of ankle fractures has previously been demonstrated to correlate with poor outcomes and increased incidence of osteoarthritis, particularly in pronation-external rotation type ankle fractures. Previous studies have focused on fibular osteotomies for correction of any shortening or malalignment. This study is relevant in also assessing tibiotalar and rearfoot valgus malalignment in pronation-external rotation type ankle fractures with correction including fibular, tibial, and calcaneal osteotomies.
Methods:
Over a 13 year period, 48 consecutive patients with mean age of 45 years were treated for malunion after a pronation external rotation ankle fracture with a tibial and fibular osteotomy. Forty-three patients had Weber type C fractures and 5 with Weber type B. The mean interval between injury and reconstruction was 20.2 months. A combination of tibial opening or closing wedge osteotomies, fibular, and calcaneal osteotomies were performed to bring the rearfoot and leg into proper anatomical alignment. Clinical and radiographic analysis was performed, with radiographs addressing arthritic changes according to Takakura osteoarthritic grading system.
Results:
The mean follow-up time was 7.1 years with all limbs maintaining a stable, well-aligned ankle. Mean tibiotalar angle was 92.8 degrees with a mean correction of 5.2 degrees; intraobserver reliability showing radiographic agreement of 0.944, 0.924, and 0.848. All but two tibial osteotomies united after a mean of 2.6 months, with the remaining 2 uniting at 6 and 7 months. Undercorrection was noted in two patients and one patient underwent total ankle replacement secondary to osteoarthritis. Subjectively, 89.4% had good or excellent results, while objectively mean AOFAS scores improved from 48 to 86. 63.8% of patients had anatomical restoration of the ankle with 10 ankles deteriorating by one stage and 11 improving by one stage according to Takakura et al osteoarthritic grading system.
Conclusions:
Reconstructive osteotomies of the tibia, fibula, and calcaneus should be considered in malaligned ankle fractures to decrease overall risk for ankle osteoarthritis. In this series, objective good to excellent clinical measurements were achieved in 93.6% of patients. An additional osteotomy below the ankle was required in 39.6% for anatomical realignment.