SLR - December 2014 - Lonny Nodelman
Reference: Wu DY, Lam KF. Osteodesis for Hallux Valgus Correction: Is It Effective?. Clin Orthop Relat Res.2014 Oct 28.Scientific Literature Review
Reviewed By: Lonny Nodelman, DPM
Residency Program: Cambridge Health Alliance
Podiatric Relevance: This article presents the author’s experience performing a minimally invasive soft tissue hallux valgus correction known as “osteodesis”. Although this is not a novel technique and was originally described in 1961, foot and ankle surgeons do not commonly perform it. The purpose of this study was to determine whether osteodesis can adequately correct hallux valgus deformity, improve patient outcomes and whether any complications are inherent to such a procedure.
Methods: This was a retrospective review of subjects who underwent osteodesis by a single surgeon. Subjects were offered this procedure if the hallux abduction angle was greater than 20-degrees or a intermetatarsal angle greater than 9-degrees in patients who were symptomatic without response to conservative care. Patient were not included if they had rheumatoid arthritis, hallux rigidus or previous foot surgery. The surgical procedure involves a single incision placed in the 1st interspace. A soft tissue release is performed by transecting the lateral collateral and fibular suspensory ligament. The distal third of the 1st and 2nd metatarsal is exposed subperiosteally. Three 2-mm drill holes are placed in the 1st metatarsal in the dorsal-to-plantar direction after which a double-stranded #1 PDS is passed and then thrown around the neck of the 2nd metatarsal. The exposed bone of the 1st and 2nd metatarsal is fish-scaled. With the forefoot squeezed the suture is tied. A medial incision is placed to remove bursae and the dorsomedial eminence of the 1st metatarsal, however, a formal osteotomy is not performed. Post-operatively, subjects were permitted to fully bear weight on the operative extremity in a custom foot brace. Subjects resumed full unprotected walking activity at 4 months post-op and full activity at 6 months. Outcome measures included the 100-point AOFAS hallux score, and radiographic assessment of the tibial sesamoid position, hallux valgus angle and intermetatarsal angle.
Results: The author performed this procedure exclusively in 70 consecutive subjects (126 feet) and 87 percent were available for 12-month follow up. All radiographic measurements improved to statistical significance (p < 0.001). The IM angle improved from 14-degrees to 7-degrees, hallux valgus angle from 31-degrees to 18-degrees and tibial sesamoid position from 6 to 3. The AOFAS score improved from 68 points pre-operatively to 96 points post-operatively. The authors stratified the data according to patient age and severity of deformity and discovered that this did not influence the measured outcomes. Correction was found to be maintained at one year after surgery. There were seven tress fractures reported in the second metatarsal (11 percent of all procedures performed). Most fractures occurred at the fourth post-operative month when patients were permitted to commence unprotected ambulation. Five patients had medial subluxation of the 1st metatarsophalangeal joint but this resolved with tapping.
Conclusions: The authors concluded that osteodesis may be an acceptable alternative to hallux valgus correction whereby a formal osteotomy is not required. Outcome measures were maintained at least one year from surgery. As addressed by the authors, there was no formal control group for comparison. As such, conclusions cannot be drawn regarding the outcomes of this particular procedure in comparison to other procedures that address hallux valgus by means of osteotomy or arthrodesis. This minimally invasive procedure required that the patient abstain from full activity for half a year and at four months post-op 11 percent of all procedures performed resulted in a stress fracture. It is proposed that future study examine the effect of a less debilitating rehabilitation protocol. Although the procedure itself may be considered minimally invasive, the post-operative rehabilitation protocol impacts the patient for a prolonged period of time, which may be avoided with procedures that involve an osteotomy or fusion with stable fixation.