Platelets are small cells found in the blood that help form clots and stop bleeding. Platelet-rich plasma is blood that contains more platelets than normal and can be given to help people with pain. Tears of the Labrum to the hip (the cartilage "suction cup" that holds the ball to the socket of the hip) cause hip pain. The study wants to see if a portion of the patient's blood, the platelets, will help relieve hip pain and function.

Participation requires completing surveys by email, text message, in person, and/or by telephone. Medical tests will also be done to track the health of participants.

Acetabular labral tears (ALT) have been reported to have a prevalence of 22-55% in patients presenting with hip or groin pain. Etiologies of ALT include femoral acetabular impingement (FAI) as the most common followed by trauma, degeneration, dysplasia, hypermobility, etc. The fibrocartilaginous acetabular labrum is an important structure in the maintenance of hip perseveration and biomechanics. Several functions include decreasing stress on articular surfaces by increasing surface contact area, maintaining a pressurized layer of intra-articular fluid to distribute mechanical forces, and assisting in joint stability. The consequences of labral pathology are not fully understood, however, prior studies have indicated that there is a correlation between acetabular labral lesions and chondral injury contributing to the development of early degenerative hip disease.

Based on current evidence, it is suggested that the highest degree of clinical accuracy in the diagnosis of a symptomatic acetabular labral tear is with a combination of clinical history, physical examination, advanced imaging such as magnetic resonance imaging (MRI) or magnetic resonance angiography (MRA), and diagnostic injection. Conservative management trials are often considered for initial treatment and include relative rest, activity modification, anti-inflammatory medication, and physical therapy with the potential for intra-articular injections including corticosteroids. If conservative management is unsuccessful, arthroscopic intervention with resection, refixation, or reconstruction is often considered. If conservative management is unsuccessful, arthroscopic intervention with resection, refixation, or reconstruction is often considered.

According to a recent systematic review and meta-analysis, there is promising evidence that platelet rich plasma (PRP) is an effective treatment for hip osteoarthritis. However, there is limited evidence regarding PRP treatment for ALT. To date, there is only one pilot study published evaluating 8 patients diagnosed with ALT who underwent ultrasound guided intra-articular hip injection with PRP. Optimistically, this study did reveal significant differences from baseline in function and pain scores at short term follow-up. However, the study lacked many important details including information about the injectate (the composition of the blood and PRP) which is vital to include in studies of these types. Therefore, the purpose of this study is to fully evaluate the effects of PRP treatment on the clinical outcomes of ALT prospectively in a larger cohort of patients.

Inclusion Criteria:

• Age ≤49 years old (i.e., 18 - 49 years old)
• Hip or groin pain with at least 1 positive provocative labral hip maneuver (i.e., Flexion, Adduction, Internal Rotation (FADIR) test, subspine impingement test, scour)
• Radiographs with Tonnis grade < 2 (i.e., 0 or 1)
• MRI or MRA hip with evidence of acetabular labral tear
• Failure of at least 6 weeks of conservative management [i.e., activity modification, non-steroidal anti-inflammatory drugs (NSAIDs), and/or physical therapy (PT), other intra-articular injection etc.]
• Prior diagnostic ultrasound guided hip injection with anesthetic-only providing ≥50% pain relief

Exclusion Criteria:

• Any prior surgery to the affected hip
• Imaging with evidence of avascular necrosis of the affected hip
• Imaging with evidence of hip dysplasia (i.e. lateral center edge angle of ≤20 degrees)
• Alpha angle of ≥55 degrees of the affected hip
• Intra-articular hip injection within the last 6 months to the affected hip of any injectate with the exception of anesthetic
• Active systemic infection requiring antibiotics or local infection at the site of the injection
• Any prior intra-articular infection of the affected hip
• Any prior fracture of the affected femur or pelvis
• Blood dyscrasia or malignancy
• Non-ambulatory patients
• Patient seeking care with active litigation pending
• Body mass index (BMI) ≥ 35 kg/m2
• Systemic inflammatory arthropathy
• Oral steroids consumed within the last three months

Some participants had two different hips enrolled in the study, which explains the difference between the number of participants and the number of hips (units) analyzed.

From enrollment until the end of follow-up, up to one month

Twenty-eight participants were at risk of an adverse event. However since some participants (n=2) had both hips enrolled in the study, there is a difference between the number of participants (n=28) and the number of hips (n=30) analyzed.

This study is limited by small sample size, convenience sampling, lack of control group, and lack of blinding. Outcomes were patient-reported without physical examination, which may have provided additional information on hip pain and function after PRP. There was wide age variability (18-49 years). Although Tonnis grade ≥2 was excluded, distinguishing traumatic labral tears from degenerative changes is difficult. Some patients required additional injections or surgery.