Risk factors for postoperative palatal fistula following repair of cleft palates, with or without associated cleft lip, in Lubumbashi, Democratic Republic of Congo

¹Department of Surgery, Faculty of Medicine, University Clinic of Lubumbashi, University of Lubumbashi, Haut-Katanga Province, City of Lubumbashi, Democratic Republic of Congo, ²Department of Surgery, Faculty of Medicine, University Clinic of Bukavu, Official University of Bukavu, South Kivu Province, City of Bukavu, Democratic Republic of Congo, ³Department of Anesthesia and Intensive Care, Faculty of Medicine, University Clinic of Lubumbashi, University of Lubumbashi, Haut-Katanga Province, City of Lubumbashi, Democratic Republic of Congo

^&Corresponding author
Dimitri Kanyanda Nafatalewa, Department of Surgery, Faculty of Medicine, University Clinic of Lubumbashi, University of Lubumbashi, Haut-Katanga Province, City of Lubumbashi, Democratic Republic of Congo

Introduction    

Cleft palates, whether isolated or associated with cleft lip, represent one of the most common congenital craniofacial malformations. The primary objective of palatoplasty is to achieve complete closure of the palate, restore velopharyngeal sphincter function for normal phonation, and minimize the impact on maxillofacial growth [1-3]. However, postoperative palatal fistula remains a feared complication, the incidence of which varies considerably in the literature, ranging from 4.9% to over 35% depending on the series and techniques used [4,5]. This complication leads to major functional consequences, including hypernasality, nasal regurgitation of liquids, and articulation difficulties, often requiring complex secondary surgical interventions. In sub-Saharan Africa, and particularly in Lubumbashi, Democratic Republic of Congo, specific data on the clinical course and predictive factors of this complication are virtually nonexistent. The constraints related to mass surgical campaigns, late patient presentation, and the significant width of the clefts at the time of consultation could influence this risk. This study aims to fill this gap by describing the incidence of postoperative palatal fistula and identifying associated risk factors (defect diameter, laterality, sex, surgical technique) in our clinical setting.

Methods     

Study setting and type: this was a longitudinal, descriptive, multicenter observational study conducted in three healthcare facilities in Lubumbashi: the Lubumbashi University Clinics, the Rwashi Military Hospital, and the Afia/Don Bosco Polyclinic. These sites were chosen because they offer free surgical campaigns and appropriate technical facilities.

Population and sampling: the study included an exhaustive sample of 63 patients with cleft palates (isolated or syndromic, with or without a cleft lip) who underwent surgery over a 14-month period. Inclusion criteria were: any patient aged at least 6 months (for a cleft velar) or 9 months (for a cleft palate) who had undergone repair surgery in one of the aforementioned facilities. Patients not meeting these criteria or whose records were incomplete were excluded.

Data collection: data were collected prospectively using a pre-established questionnaire. The variables studied included sociodemographic characteristics (age, sex), anatomical and clinical characteristics (cleft type according to the Veau classification, laterality, defect diameter measured in cm), the surgical technique used (Wardill, Von Langenbeck, Furlow, etc.), and the occurrence of postoperative complications, including fistula.

Statistical analysis: data entry and analysis were performed using Epi Info version 7.4.1 and SPSS 13.0 software. Qualitative variables were compared using the chi-square test (corrected by Yates) or Fisher's exact test. Risk was estimated by calculating odds ratios (OR) with a 95% confidence interval (CI). The threshold for statistical significance was set at p <0.05.

Ethical considerations: written or verbal Informed consent was obtained from the parents or legal guardians of minor patients, and from adult patients themselves, in accordance with prevailing ethical standards. Collected data contained no personal identifiers and were treated with strict confidentiality. The authors declare no conflict of interest.

Results     

Population characteristics: the study included 63 patients. The sex ratio was 1.1 in favor of females (52% female). The median age at surgery was 10 months (range: 7 months to 40 years), with 44.4% of patients operated on during early childhood (<1 year). According to the Veau classification, type III (complete unilateral cleft) was the most common (42.28%). The majority of clefts were unilateral (87.30%), with a predominance on the left side (66.66%). The mean diameter of the defect was 1.5 cm.

Incidence and location of fistulas: in the entire cohort, 22 patients developed a postoperative fistula (Figure 1), representing an overall incidence of 34.92% (Table 1). Regarding location, almost all fistulas (90.9%, n=20) were junctional (Figure 2), while 9.1% (n=2) were located in the soft palate. No pre-alveolar or alveolar fistulas were observed.

Risk factors associated with fistula: the Bivariate analysis (Table 2) revealed the following associations: defect diameter: a cleft diameter greater than 2 cm was significantly associated with an increased risk of fistula (OR=3.67; 95% CI: 1.00-13.34; p=0.027); laterality: bilateral clefts showed a trend toward a higher risk of fistula compared to unilateral clefts (OR=3.72; 95% CI: 0.79-17.40); although this difference did not reach statistical significance (p=0.079); sex: female sex was associated with a 2.2-fold increased risk of developing a fistula (95% CI: 0.77-6.798), but this association was not statistically significant (p=0.071); surgical technique: the Wardill technique was the most used (73.01). Although it showed a tendency towards a higher fistula rate (OR=1.5), the difference was not statistically significant (p=0.454) compared to the other techniques in this series.

Discussion     

This study reports a postoperative palatal fistula rate of 34.92% in Lubumbashi. This rate falls within the upper range of data reported in the international literature, which generally ranges from 5% to 35%, but it is higher than the averages of large series from high-income countries (often around 5% to 10%) [5,6]. This disparity may be explained by the late presentation of patients, the initial width of the clefts, and the technical constraints related to the context. The major finding of our study is the statistically significant correlation between defect width (>2 cm) and the occurrence of a fistula (p=0.027). This observation is universally recognized: a wide cleft requires more extensive dissection and generates increased tension on the suture lines, compromising the vascularization of the mucoperiosteal flaps and favoring necrosis or dehiscence [7-9].

We also noted a trend (not statistically significant, probably due to sample size) toward an increased risk of fistula in cases of bilateral clefts (OR=3.72) and in female patients. The anatomical complexity of bilateral clefts, often wider and with a free vomer, makes closure of the nasal layer particularly difficult, which corroborates the observations of other authors [10].

Regarding surgical techniques, the Wardill palatoplasty (push-back) was the most frequently performed in our series. Although this technique allows lengthening of the soft palate, it leaves areas of exposed bone laterally, which could theoretically increase the risk of fistula compared to tension-free closure techniques such as Furlow's double opposing Z-plasty or Bardach's two-flap palatoplasty [9,11]. However, our study did not show a statistically significant difference, which underlines that the surgeon's technical mastery and tension management are often more decisive than the technique itself.

Study limitations: the relatively small sample size (n=63) limits the statistical power to detect weak associations (such as the impact of sex or surgical technique) and precludes multivariate analysis. Additionally, the duration of postoperative follow-up was not uniformly extended, which could lead to an underestimation of late-presenting fistulas.

Perspectives: would the implementation, if possible, of pre-surgical orthopedic techniques (nasoalveolar molding) reduce the risk of fistula?

Conclusion     

Postoperative palatal fistula is a frequent complication after cleft palate repair in our setting, occurring predominantly at the junction of the hard and soft palates. The initial cleft width (>2 cm) represents a statistically significant risk factor for fistula development in our series.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

All the authors read and approved the final version of this manuscript.

Tables and figures     

Table 1: incidence and anatomical location of postoperative palatal fistulas following cleft palate repair in 63 patients treated across three healthcare facilities in Lubumbashi (University Clinics, Rwashi Military Hospital, and Afia/Don Bosco Polyclinic) over a 14-month period

Table 2: bivariate analysis of demographic, clinical, and surgical risk factors associated with postoperative palatal fistula after cleft palate repair in Lubumbashi, Democratic Republic of Congo (N=63, 14-month study period)

Figure 1: palatal fistula 1 month after palatoplasty according to Wardill

Figure 2: Pittsburgh classification of palatal fistulas

References