Adult acquired flatfoot

and tibialis posterior tendonopathy

Lateral column lengthening

Because of dissatisfaction with the ability of the medial displacement calcaneal osteotomy to restore arch anatomy, a number of authors have studied the effects of lengthening the relatively short lateral column of a planovalgus foot with forefoot abduction. This concept was originally popularised by Evans for treating over-corrected clubfeet and most of the older papers describe the treatment of paediatric flatfoot deformities.

Two techniques have been described:

• A transverse osteotomy of the calcaneum 10mm proximal to the calcaneocuboid joint is distracted to correct forefoot abduction and a tricortical iliac crest bone graft inserted. Various fixation techniques have been used. This preserves calcaneocuboid movement but one study found a marked increase in the pressures in the calcaneocuboid joint, raising concern that patients might eventually need calcaneocuboid fusion for OA. A subsequent study using a better flatfoot model suggested that calcaneocuboid pressure is increased in the flatfoot anyway and that calcaneal osteotomy does not chage this. The reported rate of calcaneocuboid fusion for OA after osteotomy is probably about 5%, although not all papers report this clearly. Pressures in the subtalar joint may also be increased.
• Distraction fusion of the calcaneocuboid joint also lengthens the lateral column and avoids a second procedure for OA. However, the non-union rate is about 15%.

There has been only one (retrospective) comparative series between osteotomy and fusion. All patients also had FDL transfer to the navicular. Mean AOFAS scores were 81 for fusion and 88 for osteotomy. Overall the results of the fusions were no better than the osteotomies, they took longer to recover and had more complications. However, the numbers were small and more osteotomies than fusions were lost to follow-up. The authors appear to adopted the fusion procedure later than the osteotomy, though without abandoning the osteotomy. Frustratingly, they do not comment on this change in practice, whether the treatment groups were comparable or whether there were particular indications for the fusions in later patients, or implications for the results.

Simialr results have been reported from single-procedure studies (Hintermann 1999, Moisier-LaClair 2001). Moisier-LaClair’s series had anterior and posterior (as described in the previous section) osteotomies, intending to share the displacements between the two osteotomies and reduce skin tension; wound problems may have been less frequent but 14% failed because of persistent pain.

Theoretically, lateral column lengthening should give superior correction to tendon transfer plus posterior calcaneal osteotomy alone. Series of lateral column lengthening report improvement in the arch more consistently, but the clinical scores appear similar and all studies report a lot of wound problems and lateral column pain, which may offset the possibility of improved correction. There have been no published series comparing the calcaneal osteotomy plus tendon transfer to lateral column lengthening. It may be that the lateral procedure is more effective in patients with more severe deformities (Truro stage 3), but so far there is no evidence on which to judge this hypothesis.