Acetabular labrum: Definition and lesions (What to do?)

iliac crest pain

Article reviewed and approved by Dr. Ibtissama Boukas, physician specializing in family medicine

The word labrum is a Latin word meaning "lip" or "lip". It is a fibrous cartilage that has the shape of a ring. In humans, this cartilage surrounds the humeroscapular joint and the coxofemoral joint. We speak respectively of the glenoid labrum of the scapula and of the acetabular labrum. In this article, we will focus on the acetabular labrum: definition, different types of lesion, symptoms, diagnosis and treatment of lesions.

Definition and anatomy of the acetabular labrum

On one side, the labrum is a fibrous cartilage into which thehip joint. In other words, it ensures the insertion of the head of the femur (spherical appearance) into the acetabulum (hollow shape). To allow this insertion, there is a joint capsule that attaches to the edge of the bead. This is the labrum which seals these two structures.

On the other hand, the term “acetabulum” corresponds to the joint cavity of the hip (C-shaped) in which the head of the femur is located. This bony cavity as well as the femoral head are covered with cartilage.

The labrum therefore surrounds the acetabulum with fibrocartilage. It is for this reason that we speak of the acetabular labrum to designate this fibrocartilaginous structure. You can also say " acetabular pad " or " acetabular pad because the acetabulum is nothing but the acetabulum.

Roles of the acetabular labrum

The acetabular labrum plays a few important roles.

  • It participates in increasing the depth of the bone cavity of the hip. This is why the mobility of the thigh can be accentuated in the realization of certain movements.
  • It allows to absorb the shocks due to the extreme movements of the hip by taking care of the maintenance of joint fluid in the joint. In other words, it facilitates the movement of the femoral head in the hip. It thus contributes to the protection of the cartilage layer around the femoral head and the acetabulum.
  • It plays a fundamental role in stabilizing the hip when walking. The labrum exerts and maintains a negative pressure between the head of the femur and the acetabulum. This is why the hip does not lose its grip when it oscillates during walking.
  • It is responsible for the distribution of pressure on the cartilages.

Lesions of the acetabular labrum

From one person to another, the size and shape of the acetabular pad may vary slightly. This fibrocartilaginous structure is particularly fragile. It can be affected in the event of trauma to the hip, whether it is:

  • dislocation ;
  • malformative pathology such as hip dysplasia (abnormal morphology of the femoral head or acetabulum);
  • degenerative pathology like hip osteoarthritis (hip osteoarthritis);
  • fall ;
  • repetitive strain injuries which are very common in football;
  • excessive strain on the hip;
  • femoro-acetabular conflicts: they damage the labrum by exerting strong pressure on it.

These are all possible causes that can lead to lesions of the acetabular labrum. These lesions may also be referred to as “acetabular rim syndrome”.

So, it is very common to encounter this type of lesion in athletes, dancers, gymnasts or in people whose work puts a lot of strain on the hip.

Nevertheless, it happens, in rare cases, that the origin of the lesions is not identified. They can also affect people who do not play sports.

According to specialists, the acetabular pad can suffer three types of lesions.

1. Fissure of the acetabular labrum

At the level of the acetabular labrum, a fissure may appear.

2. Disinsertion of the acetabular labrum

Part of the acetabular rim structure may disintegrate or rupture due to the formation of a “bucket handle”. This is a particular traumatic tear. It occurs at the level of the meniscus which is a fibrocartilage located between the femur and the tibia.

3. Cysts of the acetabular labrum

When the acetabulum cracks, it can leave sequelae. This fissure can in particular favor the occurrence of a mucoid cyst of the labrum.

What are the symptoms of lesions of the acetabular labrum?

In some patients, the lesions of the acetabular labrum remain silent and do not require any specific treatment. Otherwise, the lesions usually manifest as pain:

  • located at the level of hip or oldest boy ;
  • live;
  • spreading to outer thigh;
  • which can be brutal until it interferes with any movement (walking or sitting).

Besides pain, it is possible to find other symptoms such as:

  • a feeling of locking and cracking of the joint;
  • disturbance of movement even at rest;
  • a robbery;
  • painful clashes;
  • stiffness when walking;
  • a lameness...

How to make the diagnosis of lesions of the acetabular labrum?

 

To Diagnose lesions of the acetabular pad, the practitioner first performs a clinical examination. During this examination of the hip, he can observe:

  • sharp pain when performing certain movements such as hip flexion;
  • fragility in performing internal rotation movements of the thigh;
  • the limitation of articular amplitudes.

If the clinical examination suspects bulge syndrome, other imaging tests can confirm the diagnosis and identify the origin of the lesions.

  • A arthrography : it can show a failure at the level of the articular capsule responsible for the protection of the femoral head, and this, through the leakage of the contrast product. Likewise, it offers better visibility of the interior of the fissured labrum as well as of the lesion.
  • A arthroscopy : it is usually the reference examination. It consists of inserting motorized or mechanical instruments into the joint. It allows direct vision of the lesion as well as palpation of the labrum. This helps to better assess its mobility.
  • Un CT arthrography: associated with arthro-MRI (Magnetic Resonance Imaging), it can highlight the lesion of the labrum and measure its severity.
  • A hip x-ray: it identifies the cause of the lesion. It allows in particular to highlight coxarthrosis or dysplasia.

How to treat lesions of the acetabular labrum?

Who to contact in case of lesions of the acetabular labrum?

If you notice any symptoms of acetabular fold syndrome, consult one of these health professionals:

  • a general practitioner
  • a sports doctor;
  • a rheumatologist;
  • an orthopedic surgeon.

They can make the diagnosis and prescribe treatment.

What treatments are prescribed for lesions of the acetabular labrum?

There are different treatments within the framework of the treatment of lesions of the acetabular labrum.

In first intention, the doctor prescribes the hip rest during two months. Rest can be combined with treatment based on analgesics and anti-inflammatories.

When this first treatment proves to be insufficient, the doctor orders corticosteroid injections and rehabilitation. During this treatment, all sporting and professional activities that put stress on the hip joint must stop.

If the effects of the infiltrations still prove unsatisfactory, a hip arthroscopy is considered. It is a surgical intervention which consists in correcting the malformation or the deformation of the labrum. It is also necessary to remove the cyst or the loop of water. It is performed under camera, under general anesthesia and during a short hospital stay.

To learn all about hip arthroscopy (including risks and recovery), see the following article.

Sources

https://www.institut-kinesitherapie.paris/les-traitements/reeducation/labrum/

https://www.chirurgie-orthopedique-paris.com/pathologies/lesion-du-bourrelet-cotyloidien/

Back to top