The labrum is a rim of fibrocartilaginous tissue around the glenoid fossa that enlarges the socket cavity and provides stability to the head of the humerus. The labrum also connects the capsular-ligamentous structures of the shoulder joint. Labral tears can occur due to repetitive motion of the shoulder or acute trauma. In athletes with repeated anterior subluxations of the shoulder, tears of the anterosuperior labrum may occur, leading to progressive instability.
Causes
Injuries to the tissues of the rim (labrum) surrounding the shoulder rosette can occur either as a result of acute trauma or as a consequence of repetitive movements of the shoulder. For example, damage to the labrum can occur in the following cases:
- Falling on an outstretched arm
- Direct hit to the shoulder
- A sudden pull with the hand, for example, when trying to lift a heavy object
- Excessive overhead movement of the arm
Labral tears can also occur in throwers or weightlifters and result from excessive repetitive stress on the shoulder. In weightlifters, labral tears can also occur as a result of overuse during exercises such as barbell, bench, or standing presses. Posterior rotator cuff weakness can contribute to labral tears. Labral tears can occur as a result of acute injuries such as a fall on an outstretched arm, but also occur in athletes where there is intense shoulder movement (eg, golfers).
Symptoms
Symptoms of a labral tear resemble those of other shoulder injuries. Symptoms include:
- Shoulder pain is usually associated with raising the arm
- Clicking, crunching, or shoulder locking
- Sometimes pain at night or pain when doing daily activities
- Feeling of instability in the shoulder
- Decreased range of motion in the shoulder
- Decreased muscle strength
Patients with a labrum injury may describe their pain as intermittently interfering with normal shoulder function during certain activities. On examination, they may have discomfort with forced external rotation of 90 degrees, and the pain does not increase with further abduction. Often, a labral tear is manifested by a crunching or clicking sound during forced external rotation. The patient may also experience discomfort with forced horizontal shoulder adduction.
The main signs of tears of the acetabular labrum[edit | edit code]
- Acetabular labral tears are similar to meniscus tears in the knee.
- Pain in the groin or buttock, or pain that arcs around the outside of the hip joint.
- The pain is often accompanied by clicking or a feeling of obstruction in the joint.
- Ruptures can be traumatic or dystrophic.
- Dystrophic tears are common in ballet, as well as in sports that require strong hip flexion (football, mountaineering) or frequent hip rotation (golf, figure skating, martial arts).
- The abnormal structure of the hip joint (dysplasia, femoroacetabular impingement syndrome) predisposes to dystrophic ruptures.
- With hip dysplasia, the acetabular labrum is hypertrophied and prone to rupture.
- Femoroacetabular impingement syndrome involves flattening of the superior aspect of the femoral neck, which increases friction of the acetabular labrum and predisposes to labral tears and osteoarthritis of the hip joint.
- Surgical treatment of acetabular labral tears produces less predictable results than treatment of knee meniscal tears.
- The prognosis depends on the location and severity of the rupture, its nature (traumatic or dystrophic), the presence of bone abnormalities and the severity of chondromalacia.
Diagnostics
If you have shoulder pain, your doctor will first take a medical history. Often the patient remembers a specific traumatic episode followed by the onset of symptoms. The doctor will perform functional tests to determine range of motion, shoulder stability, and pain symptoms. If there is suspicion of damage to bone tissue, radiography may be prescribed. Due to the fact that radiography does not visualize the soft tissue of the articular cavity, MRI or CT is prescribed to diagnose its rupture. Both methods of examination use contrast, which makes it possible to diagnose even minor damage to the integrity of the articular labrum. In some cases, diagnostic arthroscopy is required. The tears may be located above or below the center of the glenoid cavity.
SLAP injury (tear of the labrum, front to back, with damage to the biceps tendon).
A tear below the middle of the glenoid cavity, with simultaneous damage to the inferior ligament of the shoulder, is called a Bankart injury.
Labral tears are often accompanied by other shoulder injuries such as shoulder dislocation (subluxation or dislocation).
Treatment[edit | edit code]
Conservative treatment[edit | edit code]
A labral tear usually cannot be treated conservatively. Exercise therapy can relieve muscle spasms and correct gait, and non-steroidal anti-inflammatory drugs reduce inflammation and alleviate symptoms to a certain extent, however, neither exercise therapy nor non-steroidal anti-inflammatory drugs can eliminate the source of inflammation and completely relieve the patient of symptoms. Only arthroscopy can achieve complete cure.
Surgical treatment[edit | edit code]
Hip arthroscopy allows the doctor to see the labral tear and thereby confirm the diagnosis. The goal of the operation is to remove the torn part of the lip that is hanging loose in the joint cavity and causing symptoms, while preserving the remaining intact part of the lip as best as possible. During arthroscopy, you can also examine other structures that may be causing the patient's symptoms: the articular cartilage of the acetabulum and femoral head, the ligament of the femoral head, and the joint capsule.
Special methods[edit | edit code]
Sometimes athletes with persistent severe pain in the hip joint, indicating inflammation, are injected into the joint, but this usually provides only temporary results.
Treatment
Conservative treatment for labral tears includes physical therapy, exercise therapy, anti-inflammatory treatment, and steroid injections into the shoulder. Labral tears are often accompanied by rotator cuff tendinitis. Anti-inflammatory therapy helps reduce swelling and inflammation associated with tendinitis, which helps reduce pain. As a rule, drug treatment consists of the use of NSAIDs (Voltaren, Novalis, ibuprofen, etc.). In addition, injections of steroids combined with local anesthetics into the injured shoulder at the top of the rotator cuff are possible. If necessary, the injection can be repeated. There is no point in carrying out multiple injections, since they can only mask a problem that requires more specific treatment.
Exercise therapy for labral tears begins with emphasis on the muscles of the shoulder blade and torso, abdominal muscles and lower back, and then exercises are performed to strengthen the muscles of the rotator cuff. After selecting exercises with a physical therapy doctor, you can perform the exercises yourself.
Surgery
If there is no effect from conservative treatment and symptoms persist (pain, weakness), arthroscopic restoration of the integrity of the articular labrum is recommended. During the operation, the torn cartilage is sutured and fixed using special anchors of the cartilage to the bony part of the glenoid cavity. The advantage of arthroscopic surgery is its low invasiveness and the possibility of a short stay in a surgical hospital. In addition, arthroscopic operations have a minimal rate of complications. After the operation, the arm is fixed with a splint or orthosis. Sutures are usually removed one week after surgery. Immediately after the operation, passive movements are performed and therapeutic exercises begin 2-3 weeks after the operation. Full restoration of the function of the shoulder joint usually takes 3-4 months.
Clinical picture[edit | edit code]
History and complaints[edit | edit code]
Pain from a labral tear is usually felt in the groin or upper thigh. Often, athletes, showing a sore spot, clasp the thigh with their thumb and forefinger in front and outside the hip joint so that these two fingers form the contours of the letter C. Pain can also be felt behind the hip joint, in the gluteal region. It is possible that anterior tears tend to present with pain in front of the joint (in the groin), and posterior tears tend to present with pain behind the joint (in the gluteal region).
Pain from a labral tear is often accompanied by mechanical symptoms: clicking or a sensation of obstruction in the joint. As with other diseases of the hip joint, pain can radiate down the leg, usually along the front leg, less often along the inner surface of the thigh into the knee.
The pain can be of different nature and range from mild, dull, provoked by physical activity and persisting during rest, to severe and constant, seriously limiting daily activities. Few patients have a significant limp or require crutches, but they try to avoid certain positions and movements (mainly hip flexion, abduction, and rotation) that cause pain. This usually affects their athletic performance.
Traumatic labrum rupture is primarily caused by an external force applied to a fully extended and externally rotated hip. Often an athlete can point to a specific injury, such as a fall or twisted ankle, that preceded the onset of pain.
Less commonly, the disease develops gradually, and the patient cannot definitely indicate the time of its onset. Sometimes groin pain remains after a “groin sprain,” which actually turns out to be a torn labrum.
Physical examination[edit | edit code]
Examination can usually distinguish a labral tear from the internal type of snapping hip syndrome. The patient is placed on his back and his sore leg is bent, bringing the thigh into a position of flexion, adduction and internal rotation; the pain of this movement indicates a tear of the acetabular labrum.
Combining the principles underlying the Thomas test (for hip flexion contracture) and McMurry test (for knee meniscus tear), Joseph McCarthy proposed his own test to assess the condition of the hip joint. The athlete is placed on his back with his legs bent to fix the pelvis, after which the affected leg is extended, rotating the thigh outward, and then the same movement is repeated, rotating the thigh inward. When a painful click appears, the test is considered positive and indicates a tear of the acetabular labrum. A tear in the acetabular labrum may also be indicated by pain in the groin when lifting a straight leg against the doctor’s resistance, but this is too nonspecific a sign that can also appear with other diseases of the hip joint.
Radiation diagnostics[edit | edit code]
Confirming an acetabular labral tear using existing radiological diagnostic methods is quite difficult. A plain radiograph of the pelvis in the direct posterior projection is studied (to compare the hip joint of the diseased and healthy leg) and a radiograph of the affected hip joint in the position of flexion and abduction of the hip (in the so-called frog position), but if the athlete does not have hip dysplasia, these radiographs are more likely In all, they will be normal. Subchondral cysts that arise against the background of an old rupture of the acetabular labrum indicate chondromalacia or detachment of the acetabular labrum from the articular cartilage. These cysts are most often located in the superolateral part of the acetabulum.
Femoroacetabular impingement syndrome
- one of the congenital anomalies of the hip joint, accompanied by dystrophy and tears of the acetabular lip. Its most characteristic radiological sign is the so-called pistol grip sign, that is, flattening of the anterosuperior part of the femoral neck, which is why it appears abnormally convex and, together with the femoral head, resembles a pistol grip. Bone cysts may be visible in this convex part of the neck. A study from the Mayo Clinic found that 87% of patients with acetabular labral tears had at least one abnormality on radiographs. This study included all patients with acetabular labral tears seen in the clinic over a 6-year period and was not limited to sports-related injuries.
CT and bone scintigraphy are usually uninformative. Conventional MRI cannot reliably confirm or refute a rupture of the acetabular labrum (although the detection of cysts adjacent to the labrum can be considered a fairly convincing indirect sign of its rupture). Magnetic resonance arthrography is much more informative, and since its results depend on the technique used, it must be carried out in accordance with a specific protocol. Magnetic resonance arthrography is performed in two stages: the first stage is hip arthrography with gadolinium, and the second stage is MRI of the hip using surface coils and a powerful tomograph that produces high-resolution images. It is also useful to use specially developed and computer-based protocols for scanning the acetabular labrum: they allow you to obtain a series of images in an oblique sagittal projection, in which the neck of the femur lies.
The high rate of false-negative results when using radiological diagnostic methods, including magnetic resonance arthrography, gives reason to recommend arthroscopy of the hip joint if the clinical picture is consistent with a tear of the acetabular labrum, even if no pathological changes were detected during magnetic resonance arthrography or if it was not performed .
Special methods[edit | edit code]
For differential diagnosis of pain in the hip joint, a local anesthetic can be injected into the joint under fluoroscopic control: temporary pain relief after this procedure indicates intra-articular pathology.
Comparison of diagnostic methods[edit | edit code]
The main methods for diagnosing intra-articular pathology remain questioning and physical examination - in comparison with arthroscopy (as a diagnostic standard), they allow a correct diagnosis to be made in 98% of cases. In comparison, MRI produces false-negative results in 42% of cases and false-positive results in 10% of cases, and magnetic resonance arthrography produces false-positive results in 8% and 20% of cases, respectively. Pain relief in response to local anesthetic injection into the hip joint indicates intra-articular pathology with 90% confidence, but this test is not specific for acetabular labral tears, but covers all diseases of the hip joint.