From the Research
The long-term prognosis for midfoot stability after a nonunion following Lapidus surgery is generally guarded to poor without intervention, but revision surgery with debridement, bone grafting, and rigid fixation can achieve a high union rate, as seen in a study with a 97.3% union rate 1. Nonunion of the first tarsometatarsal joint fusion (Lapidus procedure) typically leads to persistent pain, progressive deformity, and functional limitations over time. Revision surgery is usually recommended and represents the most effective treatment option. The revision procedure typically involves debridement of the nonunion site, bone grafting (often using autograft from the calcaneus or iliac crest), and more rigid fixation with plates and screws. Some key factors to consider in the management of nonunion include infection, impaired biology, and metabolic disorders, as well as the use of bone grafting, cell-based therapies, and biological adjuvants 2. Postoperative management includes 6-8 weeks of non-weight bearing followed by 4-6 weeks in a walking boot with gradual return to activities. Without surgical intervention, patients can expect continued pain, potential for worsening of hallux valgus deformity, midfoot instability, and development of secondary arthritis in adjacent joints due to altered biomechanics. Conservative measures like custom orthotics, stiff-soled shoes, and activity modification may provide symptomatic relief but will not address the underlying structural instability. The nonunion occurs because the first tarsometatarsal joint is critical for midfoot stability and proper force transmission during gait, and when fusion fails, the normal biomechanical function remains disrupted. It is also worth noting that smoking is a predictor of nonunion, and therefore, patients should be counseled to quit smoking before undergoing revision surgery 3. In terms of the specifics of the revision procedure, a study found that the use of a locking plate with callus resection and strut/cancellous bone graft provided satisfactory results in the treatment of nonunion 4. However, the most relevant and recent study on this topic found that a modified Lapidus procedure with joint compression, meticulous surface preparation, and shear-strain-relieved bone graft yields a low nonunion rate of 2.7% 1. Overall, the key to achieving a good outcome in the treatment of nonunion after Lapidus surgery is to address the underlying causes of the nonunion, use a rigorous and evidence-based approach to the revision procedure, and provide careful postoperative management. Some of the key principles of nonunion management include assessing and treating the underlying causes of the nonunion, using bone grafting and other biological adjuvants to promote healing, and providing stable fixation to allow for proper healing 2. By following these principles and using a evidence-based approach, it is possible to achieve a high union rate and improve the long-term prognosis for midfoot stability after a nonunion following Lapidus surgery.