Anatomical and clinical significance of the Cyrano long-nosed patella in combination with patellofemoral instability: a case report and review of literature

TL;DR

A rare case of patellar instability combined with a Cyrano long-nosed patella was successfully treated with a combined surgical approach, resolving pain and instability.

Contribution

This case report presents a novel surgical approach for treating patellar instability combined with a Cyrano patella.

Findings

A single-stage surgical procedure resolved symptoms of pain and instability in a patient with a Cyrano patella and patellar instability.

The Insall–Salvati index may be inaccurate for measuring patella height in cases with sagittal plane deformities.

The 2-year follow-up showed no recurrence and significant improvement in knee function scores.

Abstract

The combination of a long-nosed patella and patella alta can lead to symptoms such as anterior knee pain and patellofemoral instability.

Our objective was to address this uncommon, multifactorial cause of patellar pain and instability by a single-stage combined surgical approach.

A 14-year-old German female presented to our hospital for recurrent patellar dislocations and exacerbated infrapatellar pain during kneeling. Following physical examination and imaging, the patient was diagnosed with patellar instability combined with the rare “Cyrano”-type patella. The patient underwent a single-stage procedure that included knee arthroscopic exploration, inferior pole osteotomy of the patella, tibial tuberosity osteotomy, and dynamic medial patellofemoral ligament reconstruction. Following the surgical procedure, the symptoms of knee pain and instability were entirely alleviated, accompanied by notable enhancements in the Knee Injury and Osteoarthritis Outcome Score , Kujala Score, and Lysholm Score. Notably, no recurrence was observed throughout the 2-year follow-up period.

The entity of a symptomatic Cyrano patella may be combined with patellofemoral instability. Osteotomy and surgical excision of the long-nosed aspect of the inferior pole, coupled with the realignment of the patellofemoral joint in both coronal and sagittal planes, alleviated pain and enhanced knee joint stability, ultimately contributing to the resolution of this uncommon condition. A sagittal plane deformity of the patellar shape may significantly affect the measurement of the patella height, as the Insall–Salvati index may not correctly determine the height of a patella owing to the elongated nose.

Level of evidence IV.

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