Recurrent Patellofemoral Instability in the Pediatric Patient: Management and Pitfalls

Abstract

Purpose of Review The purpose of the review is to discuss the relevant pathoanatomy, management, complications, and technical considerations for recurrent patellofemoral instability (PFI) in the pediatric population. Special consideration is given to recent literature and management of the patient with repeat instability following surgery. Recent Findings Patellar stabilization surgery is in principle dependent upon restoration of normal patellofemoral anatomy and dynamic alignment. Historically, treatment options have been numerous and include extensor mechanism realignment, trochleoplasty, and more recently repair and/or reconstruction of the medial patellofemoral ligament (MPFL) as a dynamic check rein during initial knee flexion. In skeletally immature patients, preference is given to physeal-sparing soft tissue procedures. While medial patellofemoral ligament reconstruction has become a popular option, postoperative failure is a persistent issue with rates ranging from 5 to 30% for PFI surgery in general without any single procedure (e.g., distal realignment, MPFL reconstruction) demonstrating clear superiority. Failure of surgical patellar stabilization is broadly believed to occur for three main reasons: (1) technical failure of the primary stabilization method, (2) unaddressed static and dynamic pathoanatomy during the primary stabilization, and (3) intrinsic risk factors (e.g., collagen disorders, ligamentous laxity). Summary PFI is a common orthopedic condition affecting the pediatric and adolescent population. Treatment of repeat instability following surgery in the PFI patient requires understanding and addressing underlying pathoanatomic risk factors as well as risks and reasons for failure.

Assessing the Quality of Life Among Pediatric Population After Surgery for Recurrent Patellar Dislocation: a Prospective Cohort Study

“…One factor that is particularly important in this patient group is the status of the tibial and femoral physes [11]. While the surgical technique used for MPFL-R in this study does not usually affect the growth plate, there is still a slight risk.…”

“…Physiotherapy also has an important role comprising quadriceps programs that focus on medial to lateral balance improvement as well as walking pattern re-education and jumping techniques [9,10]. If conservative management fails to improve the patients' symptoms signi cantly, surgical treatment is the next recommended step [11].…”

Patellar mobility and lower limb kinematics during functional activities in individuals with and without patellar tendinopathy

“…Assessing for increased patellar mobility is also helpful for clinical evaluation of patellar instability which causes other symptomatic issues outside of PT, such as patellofemoral pain and patellar subluxation/dislocation. These are common in pediatric patients who are often more flexible [30].…”

The Results of Recurrent Patellar Dislocation Treatment With MPFL Reconstruction in Adolescents With a Minimum Three-year Follow-up: A Prospective Study

“…Medial patellofemoral ligament (MPFL) reconstruction has grown in popularity to become the method of choice in treating recurrent patellar dislocation (RPD). However, this growth has been accompanied by an increase in the number of novel operating techniques focussing on more targeted techniques that respond to anatomical abnormalities [1][2][3][4][5][6][7][8][9][10][11]. However, it is also important that isolated MPFL can be performed successfully regardless of the anatomical condition [12][13][14].…”

“…The analysis of the treatment should include homogenous groups of patients with regard to their age and sexual maturity. It has been demonstrated that children prior to maturation are more exposed to the risk of redislocation and need to be treated with physeal-sparing methods [9,20].…”