Müller-Weiss Disease: Midfoot Arthrodesis in Reduction vs Malreduction

Background: Midfoot arthrodesis is regarded as the main surgical approach for treating Müller-Weiss disease (MWD). This study aimed to investigate the incidence of postoperative pain during MWD treatment through midfoot reduction or malreduction during arthrodesis and to explore the factors influencing postoperative pain in patients with MWD. Methods: A total of 67 patients with MWD were recruited and divided into two groups according to whether midfoot alignment was reduced: reduction group ( n = 38) and malreduction group ( n = 29). Demographic characteristics before the operation and at the last follow-up, as well as clinical and radiographic parameters, were compared between the two groups. Clinical parameters included the American Orthopaedic Foot & Ankle Society score and visual analog scale score, whereas radiographic parameters included the calcaneal pitch angle, lateral Meary’s angle, talometatarsal-1 angle dorsoplantar (TMT1dp), talocalcaneal angle dorsoplantar (Kite angle), talonavicular coverage angle, and medial navicular pole extrusion. Postoperative complications and incidence of midfoot pain were evaluated at the last follow-up visit. Results: The reduction group exhibited better clinical and radiological parameters, including the TMT1dp and medial navicular pole extrusion, than the malreduction group at the last follow-up (all P < .05). However, the calcaneal pitch angle, lateral Meary’s angle, Kite angle, and talonavicular coverage angle did not significantly differ between the two groups (all P > .05). The overall incidence of midfoot pain was 26.4%. The reduction group showed a lower incidence of medial pain than the malreduction group (15.7% vs. 40.0%, P < .05). Regression analysis revealed that midfoot abduction, represented by the TMT1dp, was a critical factor for midfoot arthrodesis failure and that medial navicular pole extrusion was not correlated with postoperative midfoot pain. Conclusion: Midfoot reduction arthrodesis yields better clinical outcomes than malreduction arthrodesis. The TMT1dp, representing midfoot abduction, is a key factor for midfoot arthrodesis failure. The extruded medial navicular bone may not affect postoperative medial midfoot pain. Level of Evidence: Level III, retrospective comparative study.