Surgical Treatment of Solitary Periarticular Osteochondromas About the Knee in Pediatric and Adolescent Patients
Authors: Wu Mark , Zheng Evan T. , Anderson Megan E. , Miller Patricia E. , Spencer Samantha A. , Heyworth Benton E. 
Published: May 2021

Background:
Solitary osteochondromas, or osteocartilaginous exostoses (OCEs), represent the most common benign bone tumor. Despite frequently causing symptoms about the knee in younger populations, there is minimal previous literature investigating surgical treatment.

Methods:
We retrospectively reviewed the records of patients <20 years old who had undergone surgical treatment of symptomatic, pathologically confirmed, solitary periarticular knee OCE at a single pediatric center between 2003 and 2016. The clinical course, radiographic and pathological features, and complications were assessed. Prospective outreach was performed to investigate patient-reported functional outcomes.

Results:
Two hundred and sixty-four patients (58% male, 81% athletes) underwent excision of a solitary OCE about the knee at a mean age (and standard deviation) of 14.3 ± 2.24 years. Fifty-five percent of the procedures were performed by orthopaedic oncologists, 25% were performed by pediatric orthopaedic surgeons, and 20% were performed by pediatric orthopaedic sports medicine surgeons, with no difference in outcomes or complications based on training. Of the 264 lesions, 171 (65%) were pedunculated (versus sessile), 157 (59%) were in the distal part of the femur (versus the proximal part of the tibia or proximal part of the fibula), and 182 (69%) were medial (versus lateral). Postoperatively, 96% of the patients returned to sports at a median of 2.5 months (interquartile range, 1.9 to 4.0 months). Forty-two patients (16%) experienced minor complications not requiring operative intervention. Six patients (2%) experienced major complications (symptoms or disability at >6 months or requiring reoperation), which were more common in patients with sessile osteochondromas (p = 0.01), younger age (p = 0.01), and distal femoral lesions as compared with proximal tibial lesions (p = 0.003). Lesion recurrence was identified in 3 patients (1.1%). Overall, the median Pediatric International Knee Documentation Committee (Pedi-IKDC) and mean Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) scores were 97 (interquartile range, 93 to 99) and 16.7 ± 8.15, respectively, at a median duration of follow-up of 5.8 years.

Conclusions:
In our large cohort of pediatric patients who underwent excision of solitary knee osteochondromas, most patients were male adolescent athletes. Most commonly, the lesions were pedunculated, were located in the distal part of the femur, and arose from the medial aspect of the knee. Regardless of surgeon training or lesion location, patients demonstrated excellent functional outcomes, with minimal clinically important postoperative complications and recurrences, although patients with sessile lesions and younger age may be at higher risk for complications.

Level of Evidence:
Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.