Estudio clínico de la polidactilia preaxial factores pronóstico del resultado quirúrgico

1. Preaxial polydactyly, also known as radial polydactyly or thumb duplication, is the most frequently observed congenital hand malformation. Thus, there is a need for investigation into the etiology and therapeutic measures. Surgeons must maintain a critical understanding of surgical procedures, deepen the understanding of the evolution of the condition, and analyze the treatment outcomes. ‘When a surgeon makes research, he/she is a better surgeon’. 2. Genetically, preaxial polydactyly can occur sporadically, but it is more commonly observed as an autosomal dominant trait. Various studies suggest that a gene localized to chromosome 7q36 is responsible for preaxial polydactyly types II and III. 3. The Wassel classification is the universal classification for preaxial polydactyly. It was described by Wassel in 1969, and is based on skeletal anomalies. Radiological findings are used to classify cases of preaxial polydactyly into seven groups. The most frequent preaxial polydactyly types are II and IV. However, since the Wassel classification was first described, triphalangism has been progressively considered as a different condition to preaxial polydactyly, as it requires a different treatment approach. One of the limitations of the Wassel classification is that misclassification of the immature epiphysis can occur when it is incorrectly considered as a bifurcated distal epiphysis rather than a shared one in the process of development; however, this distinction is based primarily on consensus, as there is a lack of relevant clinical studies. 4. Various surgical techniques have been used to treat preaxial polydactyly. The Wassel classification not only refers to the pathoanatomy of the polydactyly, but also guides the selection of various surgical techniques. Three well-defined surgical objectives should be ensured: thumb alignment and stability, which enable optimal functionality, and an acceptable final esthetic appearance, which is very important considering the social importance of the hand. These surgical treatment aims are primarily based on relevant clinical studies. 5. Functional results in preaxial polydactyly have traditionally been evaluated using the Tada score, which is a validated functional scale that takes into account the most common and limiting complications (clinodactyly and instability), and also evaluates the range of motion of the affected joints. Recently, Dijkman showed that the JSSH assessment system provided the most reliable scoring system for preaxial polydactyly regarding the final outcomes and a comparison of results among the pediatric surgery community. However, the Dijkman scale has not yet been used in the literature. As the Tada score is still the most widely used functional scale in studies of preaxial polydactyly, we used the Tada score so that our results could be compared with previously published studies. 6. Descriptive analysis. Retrospective Cohort Study. Most of the evaluated patients had satisfactory final functional results as assessed via the Tada scale. Good functional results were achieved in 91% of patients (71% of patients had a Tada score of 5, while 20% had a Tada score of 4). Complications (clinodactyly and/or instability) were present in 27.3% of patients, which was lower than or similar to the incidence of complications reported in other series. These findings show that our surgical approach achieved successful results, and that other conditions that may have affected the functional outcome were also favorable. Prospective Cohort Study. This part of the project achieved very similar results to the retrospective analysis. Good results were achieved in 86.7% of patients (46.4% of patients had a Tada score of 5, while 40.7% had a Tada score of 4). However, this group of patients had a greater incidence of complications (51.8%) than those in the retrospective analysis group. 7. Statistical analysis. Retrospective Cohort Study. 7.1. The Wassel classification types were distributed homogeneously among all cohorts based on the age at the time of surgery. 7.2. The incidence of complications was significantly lower in the cohort aged 0 to 9 months at the time of surgery (13.9%) than in the other age cohorts (p=0.0477, chi-squared test). 7.3. Clinodactyly was significantly less prevalent in the cohort aged 0 to 9 months at the time of surgery (5.6%) than in the other age cohorts (p=0.004, gamma test for ordinal data). 7.4. There were significantly greater incidences of complications in patients with Wassel types III (55.6%) and IV (34.5%) compared with those with Wassel type I or Wassel type II (p=0.005, chi-squared test). When evaluated together, patients with Wassel types III and IV (37.5%) had a significantly greater incidence of complications than those with all other Wassel types (8.6%; p=0.002, chi-squared test). Prospective Cohort Study. 7.5. Wassel type IV polydactyly was present in 62.9% of patients, while 29.6% had Wassel type II. 7.6. Patients who underwent surgery before 14 months of age had a significantly lower incidence of complications than those who were 14 months or older (30.8% versus 71.4%; p=0.035, chi-squared test). 7.7. The proportion of patients with a Tada score of 5 was significantly greater in those who underwent surgery before 14 months of age (69.2%) than in those who underwent surgery at 14 months or older (28.6%; p=0.035, chi-squared test 7.8. There was a strong association between a lack of complications and a Tada score of 5 (p=0.000, chi-squared test). 8. Our results indicate that patients with preaxial polydactyly should be operated on at an early age, ideally before 14 months. The retrospective analysis showed that patients who were 0 to 9 months old at the time of surgery had a lower risk of complications, while this risk increased progressively with age. As surgery at early ages carries the risk of physeal lesions and is more technically challenging, we consider it reasonable to recommend surgery at around 12 months of age, and ideally before 14 months of age (based on our prospective analysis results). In addition, patients with Wassel types III and IV may have a greater risk of complications. In such cases, this increased risk should be explained to the parents, and a more specific surgical approach should be selected. This study provides clinical recommendations with a Level of Evidence of II. This is the first analysis of the association between the age at the time of surgery and final complications, and the first analysis of the statistical association between Wassel type and functional results; we will continue developing prospective studies, ideally multicentric, to confirm these findings and evaluate the mechanism. 9. According to our preliminary results, and following the aim and methodology of our project, future rigorous prospective multicentric analysis may provide more definitive evidence-based results. This may help to identify the optimal surgical method for preaxial polydactyly that obtains the best possible results with minimal morbidity, while also reducing costs. 10. More evidence-based recommendations might also be implemented in other types of congenital hand pathology surgery.