SLR - September 2023 - Smith
Title: Surgical treatment of ankle instability in children with os subfibulareReference: Zgoda, M., Arnold, M.C.A. Surgical treatment of ankle instability in children with os subfibulare. Arch Orthop Trauma Surg (2023). https://doi.org/10.1007/s00402-023-04905-y
Level of Evidence: II
Scientific Literature Review
Reviewed By: Nicole Marie Smith, DPM
Residency Program: SSM Health DePaul Hospital – Bridgeton, MO
Podiatric Relevance: Ankle sprains in children and adolescents are a common injury often treated non-surgically. However, in rarer cases due to presence of an os subfibulare accessory bone, operative treatment is required to medically manage these patients. The authors of this study aimed to assess the results of operative management in children with chronic ankle instability secondary to os subfibulare following failure of conservative management.
Methods: This level II prospective cohort study evaluated 26 children with ankle instability in pain secondary to presence of os subfibulare from January 2012 to December 2018. Nine children in the group had failed conservative physiotherapy prior to orthopedic referral. 17 children had undergone no rehabilitation and were referred for focused physiotherapy. For eight children, the guided physiotherapy was successful, and no surgery was pursued. Two children did not attend physiotherapy or follow-up. The remaining seven children and nine who had initially failed conservative treatment qualified for surgical orthopedic treatment. Inclusion criteria for the study required patients to be aged under 18, pain and symptoms of functional instability, unsuccessful physiotherapy treatment, presence of os subfibulare on ankle radiographs; willingness to participate in a study and informed consent given by the child and their parents. Exclusion criteria included patients who had previous bony injury, chronic conditions of the limb which may affect functional status of the ankle, connective tissue disease with joint hypermobility or previous surgeries to the foot or ankle. In total, 16 children were prospectively enrolled in the study group, however one patient was lost to follow-up. Surgery performed on all 15 children involved removal of identified os subfibulare as well as modified Broström-Gould lateral complex reconstruction with anchors. It is of importance to note, anterior talo-fibular ligament-- and if required calcaneo-navicular ligament—were reattached to the tip of the lateral malleolus at an area 1 to 1.5cm distal from the fibular growth plate. Children were followed up at 6 weeks, 12 weeks, 6 months and on a yearly basis thereafter. All enrolled patients’ symptoms and function of the ankle were assessed using the 100 mm Visual Analogue Scale (VAS) and Foot and Ankle Outcome Score questionnaire (FAOS) was also completed before and after surgery.
Results: 15 children (six boy and nine girls) with a mean age of 14 years and 2 months completed at least 24 months of post-operative follow-up with a mean follow-up time of 43.2 months. All children showed improvement in ankle stability. Lateral ligament reconstruction was carried out in all patients from the study with satisfactory results and no reported complications with the anchors. Care was taken during repair to avoid the physis, and there was no incidence of growth plate injury or growth arrest during follow-up visits. The mean FAOS improved from 66.8 pre-operatively to 92.3 at the latest follow-up visit. The mean VAS pain level before surgery and at the latest follow-up visit improved from 67.1 pre-operatively to 12.7. Return to sport and physical activity at school was 12.5 weeks with six children returning at a competitive level to their sport.
Conclusions: This study reports that following failure of conservative treatments, surgical excision of accessory bone with modified Broström-Gould techniques appear to be a safe and reliable method on adolescents with ankle instability and pain. Albeit a small cohort size, with lack of a control group for comparison, this study provides valuable insight regarding clinical work-up, surgical approach and post-operative management for clinicians that are presented with an adolescent patient suffering from ankle instability.