Jordy van Sambeeck

A detaching, V-shaped tibial tubercle osteotomy is a safe procedure with a low complication-rate 4 61 Aftercare Post-operative care consisted of a removable long leg plaster cast with the knee in full extension for six weeks in the period until 2014. From 2014 to the present no cast is used. Only partial weight bearing was allowed in this period, and a maximal flexion of 70 degrees. If there were no complications after six weeks, full weight bearing and full range of motion was allowed. Data analysis Complications related to the surgical procedure were classified as minor or major, according to the criteria used in Payne’s review article. [9] Major complications were defined as tibial fractures, non-union, neurovascular complications, infection and wound complications that required surgical intervention. Minor complications include events that are unlikely to have influenced the functional outcome or caused no permanent harm to the patient. Statistical analysis Descriptive statistics were used to analyse the frequency of complications as a percentage of total. A Chi –square test was performed to look at differences in male to female ratio, and an unpaired T-test to look at differences in age between the group with and the group without complications Theory/calculation This retrospective study quantifies the risk of procedure specific postoperative complications in a large group of patients related to a tibial tubercle transfer using a V-shaped osteotomy performed in a single institution. Results Two hundred and sixty-three (263) knees in two hundred and three (203) patients were included. Descriptive statistics are displayed in table 1. The median age at operation was 19 years (range 12 - 49 years). Most patients were female (73.8%). Median follow-up was 4 months (range 3 - 120 months) because standard follow- up was only up to 4 months if uncomplicated. Most frequent reasons for longer follow-up were: recurrent dislocations, postoperative complications, consultation for contralateral knee issues and request for TTO hardware removal. An overview of which specific additional procedures performed can be found in table 1. Out of the 263 knees, 144 (54.8%) had at least one additional procedure to the TTO. There was no significant difference in age between patients with and without complications (p= 0.80), but the amount of women in the group with complications was higher compared to the group without complications. (Chi- square 4.5765, p = 0.03).