Calcaneo-Cuboid-Cuneiform Osteotomy for the Treatment of Planovalgus Feet in Patients with Spastic Cerebral Palsy

The calcaneo-cuboid-cuneiform (triple-C) osteotomy is indicated for the correction of symptomatic flexible planovalgus foot deformity. This procedure allows correction of all of the varied components of the planovalgus foot deformity in a single operation^1,2.

The patient is positioned in a floppy lateral position². The calcaneus is exposed via an oblique lateral incision along the peroneal tendons. The osteotomy is performed in an extra-articular fashion beginning posterior to the posterior articular facet and extending distally and anteriorly to the inferior surface of the calcaneus. The posterior calcaneal fragment is displaced medially to allow correction of heel valgus. A separate lateral incision is made over the cuboid in order to expose it. An osteotomy is performed in the middle third of the cuboid without violating the adjacent joints and opened with a lamina spreader to allow correction of the forefoot abduction. The medial cuneiform is exposed via a medial incision. A medial and plantar-based wedge of bone is removed in toto from the middle third of the cuneiform. Closing this wedge corrects forefoot supination and recreates the medial longitudinal arch. The wedge of bone harvested from the cuneiform is inserted into the cuboid and all of the osteotomies are fixed with Kirschner wires of sizes between 1.8 and 2.5 mm or cannulated cancellous screws.

If the feet are supple enough to allow passive correction, an in-socket ankle-foot orthosis with a medial arch support can be utilized to maintain the shape of the foot and to delay deterioration and the need for surgery³. Various other surgical treatment methods are described in the literature and can be categorized as joint-sparing procedures, arthroereises, and arthrodeses. Joint-preserving procedures include the popular calcaneal-lengthening osteotomy (CLO)⁴ and the double calcaneal osteotomy⁵. Arthroereisis, a non-fusion motion-limiting technique, is minimally invasive and recently gaining popularity³. The literature has described promising results with use of this procedure⁶. Extra-articular and intra-articular arthrodesis typically have been employed for the treatment of severe and rigid planovalgus feet and in children who have limited ambulatory potential. On the basis of the currently available literature, no procedure can be labeled superior to another³.

The triple-C osteotomy is straightforward and has a short learning curve. There is no need for bone-graft harvesting and the associated morbidity thereof. Studies have shown minimal complications and low long-term recurrence with use of the triple-C osteotomy in patients with spastic cerebral palsy³.

We have reported on the short-term outcomes of this procedure². The patient would be informed regarding the ability of the surgery to correct even severe deformities⁷. The procedure is not associated with notable complications, and the primarily reported complications are related to wound healing^2,8. Although delayed healing of an osteotomy has been described by the originators of this technique¹, we have not encountered this complication. We reported good clinical and radiographic outcomes in our series of 12 feet². Moraleda et al.⁸ compared the outcomes of the triple-C osteotomy and CLO and reported similar outcomes in terms of clinical and radiographic correction, but with more frequent and more severe complications following CLO.

Protect the sural nerve during calcaneal exposure.Osteotomize the medial cortex of the calcaneus with use of an osteotome in order to avoid injuring the medial neurovascular structures.Avoid violating the adjacent joints when performing the cuboid and cuneiform osteotomies.The wedge of bone harvested from the medial cuneiform should be excised in toto to effectively lengthen the cuboid.If utilized, cannulated cancellous screws should be countersunk in the posterior cortex of the calcaneus to prevent irritation.

AFO = ankle-foot orthosisUCBL = University of California Biomechanics LaboratoryCP = cerebral palsyAP = anteroposteriorVAS = visual analog scoreCC screws = cannulated cancellous screws.