Patient-Reported and Radiographic Outcomes in Primary and Revision Stage II, III, and IV Adult- Acquired Flatfoot Deformity Surgery

CATEGORY: Hindfoot; Midfoot/Forefoot INTRODUCTION/PURPOSE: Adult-Acquired Flatfoot Deformity (AAFD) is a progressive hindfoot and midfoot deformity that causes pain and disability. It presents as a plano-valgus deformity from the failure of static and dynamic medial osteoligamentous stabilizers. Stage II presents as a passively correctable, flexible deformity of the foot; stage III presents as a fixed or arthritic deformity of the foot; and stage IV presents with marked deformity of the foot caused by failure of the deltoid ligament and subsequent peritalar instability. Although operative treatment of AAFD is dependent on the stage, there is little data on patient- reported and radiographic outcomes stratified by primary versus revision stage II, III, and IV reconstruction surgery. METHODS: Patient Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) scores were prospectively obtained on 46 consecutive patients who underwent AAFD reconstruction between November 2013 and January 2019 with minimum 12-month follow-up (average 23 months). Twenty patients underwent stage II reconstruction, 5 of which were revision surgeries; 19 patients underwent stage III reconstruction, 8 of which were revision surgeries; and 7 patients underwent stage IV reconstruction, all of which were primary surgeries. Radiographic correction was measured pre- and post-operatively and correlated with PROMIS scores. Measurements included the talonavicular uncoverage angle, talonavicular uncoverage percent, AP talo-first metatarsal angle, Meary’s angle, medial cuneiform height, and medial cuneiform-fifth metatarsal height. RESULTS: For the overall cohort, PROMIS PF increased significantly from 37.6+-5.7 to 42.4+-6.8 (p=0.0014). PROMIS PI improved significantly from 64.7+-6.3 to 54.6+-9.5 (p<0.0001). PROMIS scores were not statistically different between AAFD stages. Change in PROMIS PI was significantly greater in primary (-12.3) versus revision (-3.7) surgery (p=0.0157). Change in PROMIS PF was non- significantly greater in primary (+4.0) versus revision surgery (+2.3). All radiographic measurements improved significantly (p<0.05). In primary stage II AAFD, pre-operative PROMIS PI scores correlated with pre-operative medial cuneiform-fifth metatarsal height (r = -0.606, p = 0.0479). In addition, in primary stage II AAFD, post-operative PROMIS scores correlated with post-operative medial cuneiform height (PROMIS PF: r=0.7725, p=0.0020; PROMIS PI: r=-0.5692, p=0.0446). CONCLUSION: Patient-reported and radiographic outcomes improve significantly after AAFD reconstruction. There was no significant difference in PROMIS scores between AAFD stages. However, stage III patients had non-significantly lower improvements in PROMIS PF, likely due to loss of function after arthrodesis. Primary operations had better patient-reported outcomes compared to revision operations. In primary stage II AAFD, reconstructing the medial arch correlates significantly with improvement in pain and functionality. This survey of outcomes after primary and revision stage II, III, and IV reconstruction should help clinical decision making by providing data on expected surgical improvement.