Epidemiology of Lateral Ankle Ligament Injury: Trends in Clinical Management and Likelihood of Progression to Surgical Intervention

Abstract

Category: Ankle Introduction/Purpose: Lateral ankle ligament sprains occur frequently in both general and athletic populations. Most patients recover from their injury without complication, however, some experience persistent pain and instability following lateral ankle injury, which requires treatment with surgical stabilization. The purpose of this study is to determine the utilization and associated costs of non-operative treatment modalities, such as physical therapy (PT), non-steroidal anti-inflammatory medication, and ankle bracing, as well the incidence of lateral ankle sprains that receive surgical treatment and the costs incurred by surgical treatment of chronic lateral ankle instability. Methods: Data was collected using the Pearl Diver Humana dataset using ICD-9, ICD-10, and CPT codes pertaining to ankle sprain, ankle ligament repair or reconstruction, physical therapy, ankle brace ordering, and non-steroidal anti-inflammatory medication (NSAID) ordering. Patients diagnosed with an ankle sprain were sub-divided into three categories: non-operative treatment, surgical ligament repair, and surgical ligament reconstruction. Incidence, cost, and PT usage was compared between patient groups. Cost analysis was performed per group using associated ICD/CPT cost and physical therapy cost. NSAID use and ankle bracing use was also examined. Results: Of patients who sustained lateral ankle injury, 64% were female and 36% were male. 306,180 (98.8%) patients successfully completed non-operative management. 2,774 (1.2%) patients underwent surgical intervention. 63,276 (20.7%) non- operative patients received physical therapy, whereas 1,536 (55.4%) surgically treated patients received PT after surgery. Only 725 (26.1%) surgical patients received pre-operative PT. Median time for total PT treatment of surgical patients was 21.8 weeks, while non-operative patients received treatment for a median time of 58.7 weeks. On average non-operative patients generated 11 billed days in PT while surgical patients received 8 days of PT before surgery and 11 days in PT after surgery. Average total cost per patient was $923.32 for non-operative patients, $3,384.63 for surgical ligament repair, and $3,659.98 for surgical ligament reconstruction. Conclusion: The vast majority of patients with lateral ankle ligament sprains do not progress to surgical treatment. Patients treated non-operatively used fewer physical therapy visits per patient and generated less cost compared to surgically treated patients. Only 20% of non-operative patients received physical therapy. Additionally, a higher proportion of surgically treated patients participated in PT compared to patients treated non-operatively.