Radiographic Evaluation of First Tarsometatarsal Joint Arthrodesis for Hallux Valgus Deformity: Does the Fusion of the First to the Second Metatarsal Base Reduce the Radiological Recurrence Rate?

BACKGROUND: Modified Lapidus arthrodesis (MLA) is a well-established treatment option for symptomatic hallux valgus deformity (HVD). However, recurrence of the deformity remains a concern. The goal of this study was to evaluate the effect of an additional intermetatarsal fusion on the radiographic recurrence rate after first tarsometatarsal (TMT-I) arthrodesis. METHODS: This is a retrospective evaluation of 56 feet that underwent TMT-I arthrodesis for moderate to severe HVD. Twenty-three feet received an isolated arthrodesis of the TMT-I joint (TMT-I), whereas 33 feet received an additional fusion between the base of the first and the second metatarsal bone (TMT-I/II). Various radiological parameters were determined preoperatively, 6 weeks and at a mean of 2 years postoperatively. RESULTS: The intermetatarsal angle (IMA) and the hallux valgus angle (HVA) were significantly lowered at both follow-up evaluations in both groups. In the TMT-I/II group, the initial reduction of HVA was significantly higher (29.3° vs 21.1°). This difference disappeared by the second follow-up, leaving no significant differences between both techniques at final follow-up. Radiological recurrence rates of HVD were comparable in both groups. CONCLUSIONS: Isolated TMT-I arthrodesis provides reliable radiological results in the correction of HVD. Whether additional fusion of the first and second metatarsal base should be routinely performed remains unclear. LEVELS OF EVIDENCE: Level 3.

A cone beam CT based 3D-assessment of bony forefoot geometry after modified Lapidus arthrodesis.

BACKGROUND: Modified Lapidus arthrodesis (MLA) is a well-established treatment modality for hallux valgus deformities (HVD) associated with instability of the first ray. Although the three-dimensional (3D) nature of HVD has long been recognized, diagnostics still focus on plain radiographs. The objective of this study was to validate 3D Cone Beam CT (CBCT) in the perioperative assessment of HVD with focus on the alignment of the forefoot. METHODS: In a prospective clinical study, MLA was performed on 30 patients (25 females, 5 males; mean age: 63.2 years). Pre- and postoperatively standard radiographs and CBCT with full weight-bearing were acquired. For the CBCT based assessment, reproducible criteria have been defined, measured, and correlated with established radiological indicators. RESULTS: Evaluation of standard radiographic parameters (hallux-valgus angle [HVA], intermetatarsal angle 1-2 [IMA 1-2], distal metatarsal articular angle [DMAA], tibial sesamoid position [TSP]) showed significant improvement postoperatively. Comparison of measurements obtained from plain radiographs and CBCT were significantly correlated between both measuring techniques, indicating high reliability. Pronation of the first metatarsal and the sesamoids were significantly reduced by the procedure. Due to this repositioning effect, the second metatarsal head was elevated by 3.1mm, and the lateral sesamoid was lowered by 3.8mm. However, there was no correlation between the amount of pronation and conventional radiographic measures. CONCLUSIONS: Compared to plain radiographs, CBCT allows a more detailed view of the forefoot alignment in the coronal plain after MLA. MLA was able to recenter the sesamoids under der first metatarsal head and conversely led to elevation of the second metatarsal head.

Pedographic, clinical, and functional outcome after scarf osteotomy.

The aim of this study was to investigate whether a Scarf osteotomy for hallux valgus correction achieves a good functional restoration with pain reduction, improved mobility, and hallux loading. Therefore, we prospectively studied 32 patients who had a Scarf osteotomy for unilateral hallux valgus. We performed clinical, radiographic, and pedographic evaluations after a mean followup of 33 months to assess clinical and functional outcomes. The mean postoperative American Orthopaedic Foot and Ankle Society score was 89 points. The hallux valgus angle improved from 32.5 degrees to 6.2 degrees , and the intermetatarsal angle improved from 15.5 degrees to 6.6 degrees . The postoperative pedographic patterns showed that the maximum force and impulse decreased under the lateral forefoot and increased under the medial forefoot and hallux. The first ray became more important in the roll-over process. There was a moderate relationship between satisfaction and postoperative hallux valgus angle. The Scarf osteotomy improved the pain situation, the walking capacity, and led to an improved contribution of the hallux in the roll-over process. Therefore, this surgical procedure restores forefoot function and normalizes plantar pressure patterns.