Review of radiographic measurements following Austin bunionectomy

Scarf versus chevron osteotomy for the correction of 1-2 intermetatarsal angle in hallux valgus: a systematic review and meta-analysis

The chevron and scarf osteotomies are commonly used for the surgical management of hallux valgus (HV). However, there is debate as to whether one osteotomy provides more 1-2 intermetatarsal (1-2 IMA) correction than the other. The objective of this systematic review and meta-analysis was to compare the effectiveness of 3 types of first metatarsal osteotomy for reducing the 1-2 IMA in HV correction: the chevron osteotomy, the long plantar arm (modified) chevron osteotomy, and the scarf osteotomy. A systematic search for eligible studies was performed of the following databases: Medline, Embase (Ovid), CINAHL (EBSCO Host), and The Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Clinical Trials. Only English-language studies previous to May 2010 were included in the review. Additional hand and electronic content searches of relevant foot and orthopaedic journals were performed. Criteria for inclusion in this analysis included systematic reviews of randomized controlled trials, prospective and retrospective cohort studies, and case-control studies, as well as case-series studies involving the chevron, scarf, or long plantar arm chevron osteotomy of >20 participants with a minimum of 80% follow-up. Quality of evidence of the included studies was assessed with the Grading of Recommendations Assessment, Development and Evaluation system. All pooled analyses were based on a fixed effects model. There was a total of 1351 participants who underwent either a chevron (n = 1028), scarf (n = 300), or long plantar arm chevron osteotomy (n = 23). Only one study for the long plantar arm chevron group fitted the eligibility criteria for this review; however, it was not amenable to meta-analysis. The chevron osteotomy was associated with a mean reduction of 1-2 IMA from preoperative to postoperative of 5.33° (95% confidence interval, 5.12 to 5.54, p < .001), and the scarf osteotomy was associated with a mean reduction of 6.21° (95% confidence interval, 5.70 to 6.72, p < .001). There was a statistically significant 0.88° increase in the correction of the 1-2 IMA in favor of the scarf osteotomy compared with the chevron osteotomy. The studies included in this review were of very low- to low-quality evidence. Our findings indicate that the scarf osteotomy provides greater correction of the 1-2 IMA when used for HV correction. However, only a weak recommendation in favor of the scarf osteotomy can be made based on the low quality of evidence of the studies included in this analysis.

The multiplanar effect of first metatarsal osteotomy on sesamoid position

The standard classification system used to measure the sesamoids in the evaluation of hallux abductovalgus is a uniplanar description of a multiplanar deformity. Additionally, it cannot accurately describe a true measure of sesamoid positional change in the perioperative period because the first metatarsal is laterally transposed during corrective surgery. The intended emphasis of this investigation is to evaluate the sesamoid position in multiple planes relative to a stationary anatomical landmark following first metatarsal osteotomy for the surgical correction of hallux abductovalgus deformity. A retrospective radiographic review of 46 feet in 38 patients demonstrated statistically significant (P < .001) differences between preoperative and postoperative values for the first intermetatarsal angle, hallux abductus angle, sesamoid rotation angle, tibial sesamoid position, and tibial sesamoid grade. However, there was no significant difference in the sesamoid position in both the transverse (P = .07) and frontal (P = .29) planes when measured relative to the stationary second metatarsal. Based on the preceding results, the appropriate expected surgical outcome of hallux abductovalgus correction may be to relocate the first metatarsal on top of the relatively immobile sesamoids.

Fixation of the chevron osteotomy with an absorbable copolymer pin for treatment of hallux valgus deformity

This study investigated the use of a bioabsorbable pin made of an oriented poly-L-lactic acid/polyglycolic acid (82:18 ratio) copolymer to fix distal chevron osteotomies in 15 patients (18 feet), with an average follow-up of 18 months. This material absorbs faster than poly-L-lactic acid and slower than poly-p-dioxanone, 2 bioabsorbable polymers that have a clinical history in fixation of distal chevron osteotomies. The average intermetatarsal angle significantly decreased from 11.9+/-1.7 degrees to 0.9+/-3.8 degrees (P < .001) while the average hallux valgus angle significantly decreased from 19.4+/-4.7 degrees to 6.2+/-6.4 degrees (P < .001). The preoperative American Orthopaedic Foot and Ankle Society's hallux-metatarsophalangeal-interphalangeal score averaged 44.6+/-15.1, which increased significantly to 87.4+/-14.9 (P < .001) postoperatively. In 1 procedure, a giant cell granuloma developed that was treated with debridement. Overall, these results were comparable to those derived from the use of other methods of fixation used for bunionectomies.

Radiographic investigation of angular and linear measurements including first metatarsophalangeal joint dorsiflexion and rearfoot to forefoot axis angle

This study investigated intra- and inter-rater reliability of several radiographic angular and linear parameters using 6 subjects. Using standard weight-bearing radiographs, the following measurements were performed: first metatarsal protrusion distance, hallux abductus, first intermetatarsal, calcaneal inclination and lateral intermetatarsal angles. Measurement of lateral stressed dorsiflexion of the first metatarsophalangeal joint and the rearfoot-to-forefoot-axis angle taken using a composite view were also obtained. All parameters were measured independently by 2 raters, and measurements were repeated on 3 separate occasions at weekly intervals. Intrarater reliability of radiographic measurements ranged between R = 0.65-1.00 for lateral stressed dorsiflexion, and between R = 0.91 and 0.99 for the rearfoot to forefoot axis angle. Inter-rater reliability of radiographic measurements ranged from R = 0.82-0.99. Specifically, lateral stressed dorsiflexion showed R = 0.87 with a mean difference of -1.47 (confidence interval [CI]: -3.42, 0.47), indicating no significant difference ( t = 1.54, P = 0.13). The rearfoot-to-forefoot-axis angle showed R = 0.92 with a mean difference of -0.15 (CI: -1.05, 0.74), indicating no significant difference ( t = 0.35, P = 0.73). The 7 angular and linear measurements chosen demonstrated high inter- and intrarater reliability. These results indicate that weight-bearing radiographic first metatarsophalangeal joint dorsiflexion using the lateral stressed dorsiflexion view, and measurement of the rearfoot-to-forefoot-axis angle using a composite view could be measured reliably within and between raters.