Investigators designed this randomized controlled trial to compare the clinical outcomes of open and arthroscopic modified Broström operation for the treatment of CLAI and GJL.

The open modified Broström operation is the first line to treat chronic lateral ligament instability (CLAI). Arthroscopic techniques gain popularity for less invasivity, quick recovery to normal and sports activities, and the possibility to treat other intraarticular disorders. Studies have shown significantly poor clinical and radiological outcomes and a higher rate of failure in patients with generalized joint laxity (GJL) than patients without after open modified Broström operation. However, there is no study to compare the open and arthroscopic modified Brostrom operation for patients with GJL and CLAI. So, investigators designed this randomized controlled trial. The primary outcomes are Karlsson, American Orthopaedic Foot & Ankle Society, and visual analogue scales. The secondary outcomes are anterior displacement and talar tilt angle in stress radiography, the rate of re-injury.

Inclusion Criteria:

- Clinical diagnosis of lateral ankle pain and instability Beighton score ≥4 Age with 18 to 60 years

Exclusion Criteria:

- Patients with an acute or subacute ankle injury (within 3 months) Injury of the deltoid ligament Alignment of lower extremity greater than 5 degrees Fractures of the lower extremity Stage III or IV osteoarthritis Patients who refused to participate in the study

The demographics data, Beighton score, primary and secondary outcomes would be available to other researchers

Randomization was achieved using the opaque sealed envelopes, and each eligible patient was allocated to open or arthroscopic MBP in a 1:1 ratio with a random block assignment of 4 or 6. The envelopes were thoroughly shuffled and sequentially numbered and then opened before surgery. Patients were allowed to withdraw from this experiment.