Ultrasound-guided PRP injection for the treatment of hip osteoarthritis

Hip osteoarthritis, or coxarthrosis, usually begins gradually. Pain when walking, stiffness after periods of rest, or difficulty carrying out everyday activities are some of the most common symptoms in the early stages of the condition.

As cartilage wear progresses, many people begin to limit their movement and physical activity almost unconsciously. Walking certain distances, climbing stairs or even putting on shoes can start to become increasingly difficult.

In selected patients, particularly in the early or moderate stages of the condition, there are conservative alternatives aimed at symptom management and functional improvement before considering surgical treatment.

Among these, ultrasound-guided platelet-rich plasma (PRP) injection is one of the therapeutic options currently used in certain patients with hip osteoarthritis.

Dr Félix López, a specialist in orthopaedics, explains that “precision is particularly important in a deep joint such as the hip, because the aim is not simply to inject, but to do so precisely within the joint space and under the best possible conditions for the patient”. 

The hip and the progressive wear and tear of cartilage

The hip joint bears a large part of the body’s weight and is involved in virtually all everyday movements. Walking, climbing stairs, turning round or standing upright all depend on a joint designed to withstand load and movement for decades.

To ensure this movement is smooth, the joint surfaces are covered by cartilage, a tissue that acts as a natural shock absorber and reduces friction between the bones.

In osteoarthritis, this cartilage begins to deteriorate progressively. As the wear and tear progresses, the joint loses its range of motion and inflammation, stiffness and pain may develop.

Although each patient’s condition progresses differently, the most common symptoms include pain in the groin or on the side of the hip, difficulty walking normally, stiffness after periods of rest, or a progressive loss of mobility.

There is not always a direct correlation between the degree of wear and tear visible on imaging tests and the severity of symptoms. This is precisely why an individualised clinical assessment is essential.

 Dr Félix López during an ultrasound-guided hip injection procedure

Preserving the joint before considering a prosthesis

For years, many patients were given a relatively simple message: to live with the pain until the wear and tear made a hip replacement necessary.

However, the current approach is increasingly comprehensive and personalised. In selected patients, particularly in the early or moderate stages, there are conservative treatments aimed at relieving symptoms, improving joint function and attempting to preserve the joint for as long as possible before considering surgery.

It is within this context that ultrasound-guided intra-articular injections are used, as part of individualised joint-preservation strategies.

As Dr Félix López explains, “the aim of the treatment is not to create a new hip or to completely reverse joint wear and tear. What we are seeking is to help manage symptoms and maintain the best possible joint function in suitably selected patients”. 

The importance of ultrasound-guided injections

The hip is a deep joint surrounded by important anatomical structures. For this reason, precision is particularly important during any intra-articular procedure.

Ultrasound allows the joint to be visualised in real time whilst the needle is guided to the exact point where the treatment is to be administered. This makes it possible to confirm the correct intra-articular location during the procedure and to adapt the technique to each patient’s anatomical characteristics.

As Dr Félix López points out, “ultrasound allows us to visualise in real time where the needle is at any given moment and to confirm that the treatment is actually being administered within the joint”.

The use of ultrasound guidance has gradually been incorporated into numerous intra-articular procedures due to the ability to provide dynamic and precise monitoring during the injection.

What is platelet-rich plasma and how is it obtained?

Platelet-rich plasma, or PRP, is an autologous biological treatment obtained from the patient’s own blood through a centrifugation process carried out under controlled conditions.

The aim is to isolate and concentrate platelets, which are blood cells involved in biological mechanisms of tissue response.

Platelets contain growth factors and bioactive proteins involved in cellular signalling mechanisms. The current interest in PRP for hip osteoarthritis centres on its potential role in processes related to inflammation and the biological response within the joint in certain patients.

Once the concentrate has been obtained, the preparation is activated in accordance with specific protocols prior to intra-articular injection.

The entire procedure is carried out in a controlled clinical setting and under strict aseptic conditions.

The available scientific evidence on this type of treatment continues to evolve and may vary depending on the clinical indication, the severity of osteoarthritis and the characteristics of each patient.

Scientific interest in intra-articular biological treatments has also led to the development of international consensus guidelines aimed at improving the criteria for indication, preparation and clinical use of these therapies. The European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA), through the ORBIT (Orthobiologic Initiative) initiative, recently published a European consensus on the use of blood-derived products such as platelet-rich plasma (PRP) in osteoarthritis.

Among its conclusions, the expert group highlighted the existence of sufficient clinical and preclinical evidence to support the use of PRP in certain patients with osteoarthritis, particularly in mild and moderate stages, whilst also emphasising the importance of appropriate protocols, rigorous patient selection and the ongoing development of high-quality scientific evidence. A meta-analysis published in the *International Journal of Surgery*, which compared PRP and hyaluronic acid injections in patients with hip osteoarthritis, observed clinical and functional improvement in certain patients treated with PRP, although the authors stress the need for further studies and medium- to long-term clinical follow-up.

As the specialist explains, “PRP should not be seen as a one-size-fits-all solution for all patients with hip osteoarthritis. The key lies in selecting cases appropriately, assessing the degree of joint wear and tear, and setting realistic treatment expectations”.

In some patients, the use of hyaluronic acid may also be considered, with its suitability depending on the type of osteoarthritis, the symptoms and the functional status in each individual case.

The choice of treatment is never standardised. Every joint, every degree of wear and tear, and every patient has different needs.

Step-by-step video of the procedure

The entire procedure, from the preparation of platelet-rich plasma to the intra-articular injection in our day hospital, can be viewed in this video.

The video shows the ultrasound localisation of the joint, the preparation of the platelet-rich plasma and the injection carried out under sterile conditions and under specialist supervision.

An outpatient procedure as part of an individualised approach

Intra-articular injection is usually carried out on an outpatient basis, within a hospital setting equipped for this type of procedure.

After the patient has been prepared and the procedure carried out under sterile conditions, the patient remains under clinical supervision for a few minutes before returning home the same day.

It does not usually require hospital admission, and recovery typically allows for a gradual return to normal activities within the following 48 hours, in accordance with individualised medical recommendations.

What clinical results are currently being observed

In hip osteoarthritis, pain rarely occurs in isolation. It is frequently accompanied by loss of mobility, functional limitation and difficulties in maintaining one’s usual level of activity.

Various international studies and reviews have observed clinical improvement and pain reduction in a significant proportion of patients treated with platelet-rich plasma, particularly in the early or moderate stages of the disease.

The response, however, is not the same in all cases. Factors such as the degree of joint wear, functional status and clinical progression directly influence the results and the indication for the procedure.

In general, this type of conservative therapy tends to offer better results in selected patients and in the early or moderate stages of hip osteoarthritis, when there is still some functional margin for joint preservation.

For this reason, seeking early consultation in the event of persistent symptoms of pain or limited mobility can be particularly important. An early diagnosis allows the various available treatment options to be assessed sooner and treatment to be tailored to each patient’s individual characteristics.

In this regard, Dr Félix López emphasises that “many patients seek advice on alternatives before considering a hip replacement, and this is precisely where an individualised assessment becomes all the more important, because not all cases of osteoarthritis behave in the same way, nor do all patients require the same therapeutic approach”.

This content is for information and educational purposes only and is not a substitute for an individual medical assessment.

The information in this article is provided for general awareness and does not replace an individualised medical assessment.