Adult congenital permanent bilateral dislocation of the patella with full knee function: case report and literature review

Fixed (Congenital) Patellar Dislocation

Congenital dislocation of the patella is a rare condition characterized by lateral dislocation of the patella that is irreducible without surgical correction. Although there is no clear inheritance pattern, it is associated with several congenital syndromes. Patients often demonstrate flexion contracture, loss of active knee extension, increased tibial external rotation, and absent patella in the trochlea. Treatment requires surgical management and is comprised of lateral release, medial stabilization, quadriceps lengthening, and distal realignment. Results are generally favorable after treatment; persistent flexion contracture and redislocation are the most common complications. Further study is needed to define the optimal timing and treatment strategy for this uncommon condition.

Congenital Dislocation of the Patella - Surgical Treatment Rationale and Literature Review

INTRODUCTION

Congenital dislocation of the patella (CDP) is a rare condition and its treatment is not well defined. In CDP, patella is dislocated on the lateral aspect of the distal femur, laterally from the trochlear groove, it cannot be reduced manually and it is almost always associated with genu valgum, lateral torsion of the proximal tibia, and flexion contracture of the knee. This condition is present at birth, but the clinical findings can be subtle at birth due to the size and character of the structures being examined; early diagnosis is essential, but it may be delayed to late childhood or adulthood. If CDP is not promptly treated, the disability increases during growth, so surgical correction should be planned as soon as the diagnosis is confirmed.

CASE REPORT

We report a case of bilateral CDP associated with bilateral proximal radioulnar joint stiffness; the patient at the age of diagnosis was 11 years old and underwent a bilateral delayed surgical procedure; the 4-year follow-up results are satisfactory. Surgical treatment rationale and literature are reviewed.

CONCLUSION

Surgical correction for CDP is generally recommended, but there is no agreement in literature on the ideal treatment and in some cases, with mild impairment of the knee function, observation alone has been suggested. The decision about a surgical treatment can be difficult and depends on the degree of disability of the patient.

Extensive Lateral Release and Medial Patellofemoral Ligament Reconstruction in 25 Years of Chronic Fixed Lateral Patellar Dislocation: A 5-Year Follow-Up Case Report

Lateral dislocation of the patella is not uncommon and may impede daily activities as this causes compressive dysfunction and instabilities. Most cases of patellar lateral dislocation are due to damage to the medial patellofemoral ligament (MPFL), either rupture of detachment of the patella or femoral attachment. MPFL reconstruction alone was considered adequate for the treatment of this condition. We present a case of a 49-year-old male with chronic posttraumatic lateral patellar dislocation of the right knee of 25 years, which we treated with extensive lateral release and right medial patellofemoral ligament reconstruction with 5-year follow-up data.

Osteoarthritis with permanent dislocation of the patella treated by total knee arthroplasty through a lateral approach: A report of two cases

•

Permanent dislocation of the patella (PDP) is a rare condition. In cases of PDP with tibiofemoral arthritis, total knee arthroplasty may be performed through a medial parapatellar approach with patellar realignment in general.

•

We performed two total knee arthroplasties for PDP with lateral tibiofemoral arthritis through a lateral approach without any realignment procedure.

•

We only have 2 cases, but we suggest that TKA through a lateral approach have potential to be a new treatment option to achieve both a good outcome and repositioning of the patella.

Introduction

Permanent dislocation of the patella (PDP) is a rare condition. In cases of PDP with tibiofemoral arthritis, total knee arthroplasty may be performed through a medial parapatellar approach with patellar realignment. In this article we present two cases of PDP with tibiofemoral osteoarthritis successfully treated via lateral approach TKA without any additional realignment procedure. We performed two total knee arthroplasties for PDP with lateral tibiofemoral arthritis through a lateral approach without any realignment procedure. Mobile bearing inserts were used to adjust rotational alignment. The patients showed improved functional outcomes (Japanese Orthopaedic Association Knee score and Oxford Knee Score), and improved range of motion. Three years postoperatively, the patellae remain stable without dislocation nor maltracking, maintaining a high functional score.

Conclusion

To treat permanent dislocation of the patella with lateral knee osteoarthritis, TKA through a lateral approach have potential to be a new treatment option to achieve both a good outcome and repositioning of the patella.