CAsting and REhabilitation for osteochondral lesions of the talus in the skeletally immature: a prospective comparative observational study

An osteochondral lesion (OCL) is a lesion of the articular cartilage and
underlying subchondral bone. There is a hypothesis that OCLs in the pediatric
population are congenital and may be diagnosed by accident after trauma.
Additionally, OCLs can occur after trauma or in patients with juvenile
idiopathic arthritis (JIA). Patients experience pain during weightbearing which
can cause a significant impact on the health status of patients.
Conservative management is frequently focused on supervised neglect till
skeletally maturity has been reached. This means that patients are advised to
alter their physical activities during their growing period. Previous research
on OCLs in the knee of skeletally immature patients has shown improved
radiological and clinical outcomes after a supervised immobilization- and
rehabilitation protocol. However, as of yet, no studies describe the role of a
standardized immobilization and supervised rehabilitation protocol in the
conservative management of OCLs of the ankle in the skeletally immature
population. For that reason, a comparative study is needed in order to
investigate if immobilisation and supervised rehabilitation is superior to the
current conservative strategy.

The aim of this study is to improve the conservative management of OCLs of the
talus in the skeletally immature due to the comparison of two different
conservative strategies. An optimal conservative treatment can result in a
better quality of life and help to avoid surgical management when patients are
skeletally mature.

Potential candidate and their parents/caretakers will be provided with
information about the study. If patients confirmed their participation, they
will be assigned to the intervention or control group based on personal
preference. Patients in both groups will be followed up with questionnaires
concerning ankle function, ankle pain and returning to sport. Questionnaires
will be taken at the following moments: baseline, 16 weeks, 26 weeks, 52 weeks,
104 weeks. X-rays, CT-scans and MRI's will be conducted at baseline.
Subsequently, MRI's and X-rays will be conducted at 52 weeks and 104 weeks.

Patients in the intervention group will undergo non-weightbearing
immobilization with a cast for 8 weeks in phase one. 4 in a circular cast with
non-weightbearing followed by 4 weeks toe-tip weightbearing (10-20% of body
weight) in a walking boot during daytime and a removable cast at night. In
phase 2, a supervised rehabilitation will be performed till week 16 after which
phase 3 will start at week 16-18 In phase 3, patients will resume running,
jumping and acyclic sporting activities under supervision of a physical
therapist.

The extra burden that participants of this study will have is completing the
questionnaires at the above mentioned moments. The completion of all
questionnaires at each follow-up moment will take approximately 30 minutes.
Subsequently, patients will have radiologic follow-up at baseline, 16 weeks, 1
year, 2 years, 5 years and 10 years. Only the radiologic follow-up at 16 weeks,
5 years and 10 years is an extra burden in context of this study.
Participation in this study does not involve any risks.