SLR - May 2014 - Danielle DiStefano
Biomechanical Assessment of Flexible Flatfoot Correction: Comparison of Techniques in a Cadaver Model
Reference: Zanolli D, Glisson R, Nunley J, Easley M. Biomechanical Assessment of Flexible Flatfoot Correction: Comparison of Techniques in a Cadaver Model. The Journal of Bone and Joint Surgery, American. 96 (2014): e45(1-8).
Scientific Literature Review
Reviewed By: Danielle DiStefano, DPM
Residency Program: University Hospital – Newark New Jersey
Podiatric Relevance: Adult acquired flatfoot is commonly caused by the tibialis posterior tendon dysfunction with worsening deformity justifying surgical intervention. Surgical correction of stage II flatfoot commonly requires addressing both osseous and soft tissue components in the operating room. This study attempted to evaluate which surgical procedure was most effective for correcting flatfoot.
Methods: Stage-IIB (flexible) flatfoot deformity were created in 10 cadaver feet through transection of various ligaments. Subsequently, the cadavers were mechanically loaded. Six surgical procedures were then performed and evaluated: (1) lateral column lengthening via calcaneal osteotomy, (2) medial displacement calcaneal osteotomy with FDL transfer, (3) treatment one and two, (4) treatment three plus “pants over vest” spring ligament repair, (5) treatment three with spring ligament repair with use of the distal posterior tibialis tendon stump, (6) treatment three with spring ligament repair with suture anchor. Clinometers were inserted into the talus and first metatarsal to measure metatarsal declination. This represented sagittal plane alignment. A clinometer was also placed in the talus and navicular to assess coronal plane correction. Metatarsal dorsiflexion and navicular eversion were assessed pre-procedure and periodically throughout loading after the procedures were performed.
Results: “Arch flattening” improved by approximately 5 degrees depending upon the procedure. Furthermore, talar-navicular correction improved by 2 degrees, based on procedure choice. Treatment two had the least significant effects both initially and during post-procedure loading compared to the remaining treatments. Spring ligament repair appeared to have no significance as well.
Conclusion: This paper suggests that spring ligament repair has little bearing on improving a flat foot deformity. Additionally, lateral column lengthening procedures seemed to have the most dramatic effect on correcting flatfoot deformity in the sagittal and coronal midfoot. Furthermore, medial calcaneal slide with FDL transfer had the least effect on flatfoot correction.