Femoroacetabular impingement syndrome (FAIS) is a condition caused by an abnormal bone structure that causes the bones on either side of the hip joint to impinge on each other during certain movements, thus causing pain. This condition can be surgically treated with hip arthroscopy. For patients undergoing hip arthroscopy, there are currently two protocols related to how they may bear their weight after surgery: 1) Delayed Weightbearing: Patients use crutches and put very little weight on the surgical side. After 6 weeks, they are able to bear weight, 2) Immediate Weightbearing: Patients bear weight on the affected side, as tolerated, immediately after surgery with crutches for additional support. They are then permitted to stop using the crutches in the weeks after surgery as they feel comfortable and are stable on the operative leg.

The purpose of this study is to determine whether immediate or delayed weightbearing protocols following hip arthroscopy impact patient outcomes and complication rates. Participants will be randomly allocated into one of the two aforementioned groups, and followed up for 2 years to assess function and patient-reported outcomes.

Hip arthroscopy is used in the surgical treatment of femoroacetabular impingement syndrome (FAIS). There remains debate as to whether patients should be restricted to touch weightbearing post-operatively to prevent complications and improve clinical outcomes. This study aims to assess whether early weightbearing will produce non-inferior patient reported outcomes compared to protected touch weightbearing at 1 year post-operatively. We hypothesize that patients who are allowed to bear weight immediately after surgery will have non-inferior outcomes in comparison to those allowed to bear weight at 6 weeks post-operatively.

The FASTHIP trial is a multi-center, non-inferiority randomized controlled trial, looking at patients who are 16-50 years old, undergoing hip arthroscopy and osteochondroplasty for femoroacetabular impingement syndrome. All patients will be under general anesthesia, supine on a traction table. They will then undergo hip arthroscopy and associated procedures according to their respective surgeon's typical practice. This will result in different surgical techniques being represented in this study, with variances in portal placement, bone resection strategy, labral repair strategy and capsular closure technique. This is meant to reflect the true practice variances among hip arthroscopists and is inherent in the pragmatic nature of the trial. Participants will be randomized into one of two groups (immediate weightbearing as tolerated vs. touch weightbearing for 6 weeks following hip arthroscopy) in a 1:1 fashion using a computer-generated randomization schedule. Following surgery, all participants will receive a post-operative prescription of acetaminophen for three days, followed by Celebrex daily, and a conservative number of opioids for pain control. All participants will also receive standardized physiotherapy instructions outlining a phased approach from early joint protection and range of motion, to strengthening and sport specific goals in subsequent months. Initially, patients will be restricted to: hip extension 0, flexion 90, abduction 0, adduction 30 and limited external, internal rotation. At 6 weeks patients progress to full ROM and strengthening exercises. Return to sport targets instructions will be patient and sport specific, but generally recommended at 6 months.

Following screening, consent, collection of baseline data, and surgery, patients will be seen post-operatively at 2-weeks, 6-weeks, 3-months, 6-months, 1-year, and 2-years. Patient reported outcomes will be collected at 6 weeks, 3 months, 6-months, 1-year and 2-year appointments.

Inclusion Criteria:

• Diagnosis of femoroacetabular impingement syndrome (FAIS)
• Booked for hip arthroscopy surgery and osteochondroplasty for FAIS at a participating site
• English literate

Exclusion Criteria:

• Prior hip surgery, arthroscopic or otherwise
• Workplace Safety and Insurance Board/medicolegal claim, complex regional pain syndrome, fibromyalgia, pain syndrome diagnoses, regular opioid use beyond 50mg morphine equivalents per day
• Hip dysplasia, Legg-Calve-Perthes disease or slipped capital femoral epiphysis, Arthritis > Tonnis 1
• Chondral matrix repair, microfracture/osteoarticular transfer system (OATS)

Neither the patient nor their surgeon will be blinded. However, outcome assessors will be blinded throughout the duration of the study. Assessors will screen for complications at follow-up visits.