# A Systematic Review of Osteotomies to Correct Hallux Valgus in the First Metastasis
## 3 Results
### Distal Chevron Metastasis Osteotomy
#### 3.2.2 Follow-up and Biomechanical Analysis  
A multicenter retrospective study involving four hospitals was carried out by [PERSON] et al. [13]. The authors analyzed 45 feet from 38 patients who received DCMO for HVA with metatarsus adductus (MA) and had at least one year of post-operative follow-up. The HVA and the IMa were measured, which improved by 24.5\({}^{\circ}\) and 7.3\({}^{\circ}\), respectively. The MA angle (MA\(\bar{\text{a}}\)) and the degree of the lateral sesamoid were maintained, with no differences in the pre-and post-operative periods between the two groups created with mild MA (18\({}^{\circ}\)\(\leq\) MA\(\bar{\text{a}}\) \(<\) 20\({}^{\circ}\)) and moderate (20\({}^{\circ}\)\(\leq\) MA\(\bar{\text{a}}\)). Only the mean post-operative IMa showed a difference between the two groups. Foot function index (FFI) and visual analogue scale (VAS) were recorded, and both improved significantly. When the extent of improvement was compared between the two groups, no significant differences existed in any category. The total recurrence rate (HV\(\bar{\text{a}}\)\(\geq\) 20\({}^{\circ}\)) was 11.1% (5/45), and although the moderate group (4/29, 13.8%) had a higher proportion than the mild group (1/16,  
Figure 6: Distal Chevron metatatarsal osteotomy. Representation of the lateral translation after angular sawing. 6.3%), this was not statistically significant. In conclusion, DCMO for HV patients with MA had satisfactory radiographic and clinical results with minimal recurrence; [PERSON] et al. [14] reinforce this conclusion, stating that it is a less invasive procedure with good clinical prospects and positive results. Except in cases of severe combined deformity, they were recommending isolated DCMO without any procedure or manipulation of the other metataralsals as a viable treatment option. Presently, plantar pressure distribution measurement has revealed itself as essential for detecting and diagnosing specific pathologies and plantar deformities. This methodology can help to study the structures and pathologies of the foot, aiding in diagnosis, but can also help in choosing treatment, prevention, and rehabilitation. By studying plantar pressure distribution, it is possible to develop solutions to improve the distribution of these pressures in the patient's daily life. Peak pressure (PP) is the most commonly used plantar pressure variable to express foot loading. This value represents the maximum load in an area under the foot during one step [27; 28; 29]. However, several other variables can be obtained from this type of equipment. The market currently offers various equipment that allows the analysis of plantar pressure distribution. There are two main types of methodology for evaluation of plantar pressure distribution: (a) plantar pressure distribution under the foot, obtained with an instrumented fixed platform; (b) plantar pressure distribution inside footwear, obtained with instrumented insoles. Figure 7 shows an example of left and right foot plantar pressure distribution with seven anatomical masks to allow separate observation of different foot regions. [PERSON] et a. [15] used EMED-SF Pedography Analyzer,(tm) (Novel GMBH, Munich, Germany). The pressure platform comprised a 32 \(\times\) 62 sensor matrix with two sensors per cm\({}^{2}\) resolution. The sampling frequency was fixed at 70 Hz and auto-triggered to enable first contact with the platform to commence collection. The threshold for collection was 10 Kpa. The data were then stored. [PERSON] et al. [16] used Pedar system insoles (Novel GmbH, Munich, Germany). These are 2.5 mm thick and contain 99 capacitive pressure sensors distributed across the insole. The insoles were regularly calibrated throughout the study period according to the manufacturer's guidelines. According to the authors, PP for the central forefoot (CFF) increased post-surgically. However, pressure time integral, force time integral, and contact time were unchanged in the CFF region.