Surgical management and postoperative evaluation based on morphological classification in central polydactyly of the foot

Central polydactyly of the foot: An experience of a treatment of 22 patients

BACKGROUND

The central polydactyly of the foot is a rare congenital disorder, and its characteristics are not well known. This study aims to investigate its disease concept.

METHODS

We obtained the medical records of patients who were treated surgically for central polydactyly of the foot at our hospital during a 32-year period from 1990 to 2021 retrospectively. We compared our clinical data with other case series reports to investigate the characteristics of this disorder further.

RESULTS

There were 22 patients (13 males and 9 females) included in our case series. Unilateral and bilateral involvements were observed in 19 (right side: 6 patients; left side: 13 patients) and 3 patients, respectively. The second toe is the commonest duplicated toe (observed in 19 toes). 19 patients had distally duplicated toes (with normal metatarsal bone). Proximally duplicated toes were observed in only two patients.

CONCLUSIONS

The incidence of central polydactyly of the foot is almost equal among male and female, and bilateral involvements are few. As this abnormality is rarely reported, further investigations are needed to clarify the clinical presentation of central polydactyly of the foot.

Update of surgical treatment of polydactyly

PURPOSE OF REVIEW

Polydactyly presents with variable extent of duplication and may involve preaxial/radial (hand)/medial (foot), postaxial/ulnar (hand)/lateral (foot) or central duplication. This review will summarize recent advancements in the surgical management of this common entity.

RECENT FINDINGS

Modifications to classification systems aim to help guide surgical management of polydactyly. Attempts have been made at quantifying preoperative angulation of the duplicated digits to minimize the chance of residual or recurrent deformity after surgical reconstruction. As a result, consideration should be given to the need for soft tissue correction vs. osteotomy to optimize the clinical outcome. On-top plasty is an option that may be beneficial in 'unequal' preaxial polydactyly, where neither duplicate is preferred on its own.

SUMMARY

Polydactyly is one of the most common congenital anomalies in the hands and feet. Determination of surgical intervention often begins with classification systems that exist, which primarily separate these into preaxial, postaxial, and central. Referral for surgical consideration is indicated, given the management is often surgical.

Rotational osteo-onychocutaneous flap for central polydactyly of the foot: A novel technique for correction of the deformity

Eccentric location of two nails like eyes of a bird are frequently observed in central polydactyly of the foot. A novel technique of rotational osteo-onychocutaneous (OOC) flap procedure is introduced to correct this deformity. Six children with central polydactyly of the foot who showed eccentric locations of nails were operated by this technique. Four patients were distal phalangeal type, and two middle phalangeal type. Preoperatively the angulation deformity of distal phalangeal type was average 16.8 (range, 2.3-48.0) degrees, and middle phalangeal type 10.3 (range, 2.9-17.7) degrees. The rotational OOC flap procedure was performed at average 24 (range, 12-51) months of age. Cosmetic and radiographic assessments were done after an average of 42 (range, 6-79) months of follow-up. All patients and their parents were satisfied with the cosmetic results. The angulation deformity was improved to average 4.2 (range, 0.5-11.2) degrees in distal phalangeal type, and 5.9 (range, 2.0-9.8) degrees in middle phalangeal type, respectively. Postoperative residual angulation deformity measured by simple radiographs were less than 5° in all patients. Complications such as partial necrosis of the flap were not found. In conclusion, our novel technique of rotational OOC flap procedure resulted in satisfactory outcome for patients with 'eyes of a bird' type toe nail deformity of central polydactyly of the foot. It corrected the angulation and rotational deformity of the toe nail of the main digit without causing any complications.

Operative Technique and Management of Central Foot Polydactyly

Polydactyly is characterized by the manifestation of supernumerary digits in the hands and feet. It can be isolated or associated with a genetic syndrome. Based on the location of duplication, it is categorized as preaxial, postaxial, or central. The latter is a rare abnormality, comprising approximately 6% of cases. There is a paucity in the literature regarding this congenital anomaly and its overall management. Nonoperative treatment is generally unsuccessful in managing symptoms such as excessive width, abnormal digit alignment, and growth. Though surgical management addresses the individual patient's needs, general goals include preservation of digits with the greatest axial alignment, resection of symptomatic digits, alignment correction of the remaining great toe, stabilization of the soft tissues, and adequate soft tissue coverage. This study aims to delineate effective operative techniques for central foot polydactyly. Two patient cases are discussed, providing a framework for pre and postoperative care, complications, and outcomes. The techniques detailed offer a straightforward, efficacious, and safe method to reconstruct central foot polydactyly, returning form and function to the patient.