Mid-term results of giant cell tumours with pathologic fractures around the knee: a multicentre retrospective study

The aims of this work are to present a classification of "complex fracture" and "simple fracture", to compare their features, treatments and prognosis in patients with giant cell tumour with pathologic fractures around the knee, and to determine the best surgical method for patients who have giant cell tumour around the knee with different degrees of fracture.

Data from 130 patients with pathologic fractures from giant cell tumour around the knee who underwent surgical treatment from March 2000 to November 2015 at 6 institutes around China were collected and analysed. A multicentric study design was used to explore the epidemiological features and to compare differences in the surgical procedures and prognosis of the two fracture groups. The mean age at diagnosis was 37.1 years old (range, 13-77 years). The median follow-up was 126.5 months, ranging from 68 to 370 months.

The general clinical and imaging features of the groups of patients with simple and complex fractures, namely, sex, age, the lesion site, living or working environment, eccentric growth patterns, Campanacci grading system, and duration of symptoms before treatment, showed varying degrees of differences, but with no statistical significance (p > 0.05). The incidence rate of surrounding soft tissue mass was 35.2% (32/91) in the group with simple fractures, whereas it was 87.2% (34/39) in the group with complex fractures, which showed a significant difference (p < 0.05). Wide resection and reconstruction with joint replacement were performed more often in patients with complex fractures (61.5%, 24/39). Intralesional procedures were performed more often in patients with simple fractures (56.0%, 51/91). The difference showed significant differences (p < 0.05). The local recurrence rate was 17.6% (16/91) in the group with simple fractures, whereas it was 10.3% (4/39) in the complex fracture group, showing a significant difference (p < 0.05). A total of 2.3% of patients (n = 3,3/130) developed a skip lesion. The complication rates were 4.6% (4/87) and 14.7% (5/34), respectively, in the two groups with simple or complex fractures, showing a significant difference (p < 0.05). The mean MSTS and TESS scores with simple fractures were 26.6 (range, 13-30) and 84.1 (range, 29-100), respectively, whereas the mean scores in the group with complex fractures were 25.5 (range, 18-30) and 78.3 (range, 30-100), respectively, also showing a significant difference (p < 0.05).

Our classification of "simple fracture" and "complex fracture" could guide decisions regarding the best surgical method for lesions in patients who have giant cell tumour around the knee with different degrees of fracture.