Orthopedic complications can be injuries or diseases that affect the bones, muscles, and joints. Hemarthropathy is due to bleeding disorders, most commonly hemophilia, and can result in severe issues related to chronic amounts of blood in the body's joints. This causes swelling, pain, and loss of joint function. A serious barrier to treating many patients with bleeding disorders creates higher health risks and costs. Platelet-rich plasma (PRP) injection is a method that can reduce the cost of care while still offering a similar standard of care for patients.

This study intends to show that low-cost PRP can be done safely in patients with bleeding disorders, without the need for expensive equipment, while monitoring patient treatment results. Study participants will receive injections for joint conditions. Being in the study requires attending 1 to 2 in-person visits at the study clinic. Participants will also complete surveys using email, text messages, in person, and/or on the phone. Participation lasts about 6 months.

This study will be performed as a prospective, single arm study. Consecutive patients eligible for a standard-of-care injection will be enrolled from the Utah Center for Bleeding and Clotting Disorders. The University of Utah non-operative sports medicine team currently performs hundreds of injections monthly, and the PI works closely with the orthopedic complaints of patients with bleeding disorders. From a research standpoint, the investigators have successfully performed numerous randomized controlled prospective trials on a variety of musculoskeletal conditions in the past and have already validated this method on a large cohort of patients with knee osteoarthritis (OA).

Potential subjects will then be approached by a member of the research team to discuss the consideration of taking part in the study if they meet the inclusion criteria of this study project. Using all forms of good clinical practice, a member of the study team will review with the participant the Informed Consent Form, allow participant to read the informed consent (ICF) and ask questions prior to signing the ICF. Potential subjects may also be asked by other physicians or staff members familiar with the study.

Low Cost-Platelet Rich Plasma (LC-PRP) preparation method: See Documents for full details. This method follows the same procedures as the standard-of-care, FDA-cleared method used by numerous commercial machines; thus it does not require additional FDA clearance or approval. To summarize the full method in the appendix, 45mL of blood is drawn from the subject in a standard-of-care manner into 3 x 20mL syringes, each containing 2mL of sodium citrate (anticoagulant). Each syringe is prepared and capped, then placed into a centrifuge. The resulting separated blood is then drawn off into a single new sterile syringe, which can be used for the injection. Blood and PRP analysis: The investigators will perform a full analysis (a complete blood count (CBC) with differential) on subjects' whole blood and their prepared LC-PRP. Importantly, the investigators will include all data required in the PRP minimum reporting standards, including "platelet, differential leukocyte, and red cell analysis of all samples." Also note that although the investigators are collecting these values for the purposes of the study, CBC values are not needed in the community.

Injections: A total of 20 joints (estimated 10-15 patients) will receive injections, performed at day 0 and 3 weeks, for a total of two injections - two injections have demonstrated superior outcomes to one, and will increase our number of injections to improve the proof of feasibility. All subjects will receive ultrasound-guided intra-articular joint injections by an experienced sports medicine provider after local anesthesia with 1% lidocaine to the extra-articular structures, namely the skin and joint capsule, to increase comfort. Note: though the investigators are using ultrasound guidance to ensure that they are guaranteeing accurate injectate placement for this study, this is not necessarily required in the community setting. These will be performed after the patient's typical factor infusions, if applicable.

Questionnaire: The investigators will collect demographic information along with baseline and subsequent functional patient reported outcomes, namely the WOMAC (knee), FAOS (ankle), and the QuickDASH (elbow). REDCap will be used to administer surveys and store data. The investigators will additionally ask about adverse events, pain, global satisfaction, global injection satisfaction, and medications.

Data collection time points and follow-up: Follow-up data (see timeline below) will be administered electronically. Subjects will be queried by email, text message, in person, and/or by telephone regarding treatment outcomes at 0, 1, 3, and 6 months after the second injection. Three months will be the primary endpoint, and six months will be an exploratory, unfunded endpoint.

• LC-PRP Outcomes: As this is a feasibility study, it is likely that this study will be underpowered for clinical outcomes. However, the investigators will still monitor pain and the above outcome measures and identify potential time-related improvements.
• Economic Evaluation: The investigators will track staff-, time-, equipment-, and supply-related costs to accurately identify costs associated with each injection. This will ensure that costs are accurately recorded.

Inclusion Criteria:

• Patients of any adult age with symptomatic hemarthropathy of the ankle, knee, or elbow, based on radiographs within the last 24 months.
• Patients must have failed at least six weeks of conventional conservative treatments (such as medication or physical therapy).

Exclusion Criteria:

• Exclusion criteria will include recent (last two years) surgery to the affected joint, prior joint replacement.
• Prior orthobiologic injection into the affected joint.
• Thrombocytopenia
• Inability to receive factor prior to PRP injection.
• Active systemic or local infection at the site of injection,
• Non-ambulatory patients
• Body mass index (BMI) over 50
• Recent (six month) or current corticosteroid injection/intake.

Patients with hemarthropathy in multiple joints will be eligible for up to 2 joints if multiple fit the criteria.

Some participants had two different joints enrolled in the study, which explains the difference between the number of participants and the number of joints analyzed.

From enrollment, to 6 months

This study was a single-arm pilot with a small sample size and no control group, limiting the ability to draw causal conclusions or evaluate statistical significance. The study population was drawn from a single center, potentially limiting generalizability. Larger, multi-site randomized trials are needed to confirm reproducibility, efficacy, and define optimal dosing strategies.