SLR - February 2018 - Keval G Parikh
Reference: R. Chatellard, J Berhouet, J Brillhault. Efficiency of Locking-Plate Fixation in Isolated Talonavicular. Journal of Orthopaedics and Traumatology: Surgery & Research 102S (June 2016) S235-S239.Scientific Literature Review
Reviewed By: Keval G. Parikh, DPM
Residency Program: UF Health Jacksonville, Jacksonville, FL
Podiatric Relevance: Talonavicular (TN) joint fusion is an effective means of treating rearfoot deformity. Due to the increased motion in the talonavicular joint, the rates of nonunion are relatively high. The study assessed the radiological and clinical results in isolated TN joint fusions by using two retrograde compression screws and a dorsal locking plate.
Methods: This is a level IV retrospective single-surgeon study. It included 26 TN fusions performed within 25 patients. Mean follow-up was 14.9 +/- 8.7 months. Bone fusion and anatomic results were assessed on DP, lateral and Meary weightbearing radiographs. Surgical technique included an Achilles lengthening with a triple hemisection to increase ROM in the sagittal plane. After the joint was properly prepped, final fixation was done with two 3.5 mm retrograde compression screws. The first was from the navicular tuberosity to the talar neck. The second screw was positioned laterally. Stress was neutralized with a dorsal plate with uniaxial locking screws.
Results: The series included 26 cases, of 25 patients. Radiological fusion was achieved in all cases at a mean of 2.7 +/- 0.7 months. The AOFAS scores increased from 37.2 preoperatively to 79.4. Mean VAS diminished significantly from 7.1+/- 0.9 to 2.4+/-2.2.
Conclusions: TN joint fusions by a conventional fixation by K-wires, staples or screws show a relatively high rate of nonunion at approximately 35 percent. This particular study had multiple limitations, including the small sample size, heterogeneous pathologies and lack of assessment of the reproducibility of the radiographic analysis protocol. The radiological consolidation seen in this case study shows that the construct of two retrograde compression screws in conjunction with a dorsal locking plate can provide increased stability and better rates of fusion. Although the fixation may seem cumbersome and costly, it provides optimization for consolidation.