Labral Tear

Definition/Description

An acetabular labral tear can cause pain if the labrum is torn or damaged. Labral tears cause pelvic pain or pain in the front of the pelvis and rarely cause pelvic pain.[1] This mechanical pathology is thought to be caused by excessive forces on the hip joint. For example, a tears can reduce the acetabular contact area and increase stress leading to cartilage damage and hip joint deformity.[2]

Labral tears can be further classified as:

• Anterior labrum tear – Pain is usually more consistent and located in the anterior hip (anterior upper quadrant) or groin. [3][4][5][6][7][8] They frequently occur in individuals in European countries and the United States.
• Posterior lip tear – located in the lateral area or deep in the back of the buttock. They occur less frequently in individuals in European countries and in the United States, but are more common in individuals in Japan. [3][5][7]

Clinically Relevant Anatomy

The acetabular labrum is the fibrocartilaginous rim that surrounds the acetabulum. It helps hold the femoral head in the acetabulum and can vary widely in shape and thickness.

The labrum has three surfaces:1

1. Inner surface of the joint – adjacent to the joint (without blood vessels)
2. Outer joint surface – contacts joint capsule (vascular)
3. Basal Surface – Attaches to the acetabular bone and ligaments.

The transverse ligament surrounds the hip and helps hold it in place as it moves.

In the anterior aspect the labrum is triangular in radial aspect. On the dorsal side the labrum is triangular but distally rounded.[9][10]

The functions of the acetabular labrum are:

• Joint stability
• Sensitive shock absorber
• Joint lubricator
• Pressure distributor
• Reduced stress related to the interaction between the acetabular and femoral cartilage[5][11][1]

Epidemiology/Etiology

In studies of patients with labral tears, researchers have attributed the injury to a variety of factors:

• Direct trauma – e.g. car accident crash with or without a collapsed hip fracture
• Sports applications requiring frequent field turns or excessive extension – e.g. ballet football and hockey track and field
• Specific features include torsional or twisting movements hyper abduction hyper extension and hyper extension with external rotation

The condition is age-related. The reported age of people with hip pain and hip dislocation ranged from 8 to 75 years.

Systemic risk factors for the condition include:

• Acetabular dysplasia
• Degeneration
• Capsular laxity and hip hypermobility
• Femeroacetabular impingement (FAI) (Byrd and Jones 2003 Wenger et al 2004)[2]

Characteristics/Clinical Presentation

• Gender – Occurs in both sexes at equal frequency[12][8][13][14].
• Symptoms – Persistent dull ache accompanied by severe pain that worsens with activity. Walking, spinning, prolonged sitting, and impactful activities can aggravate symptoms. Some patients describe nocturnal pain [1]. Symptoms can last for a long time, averaging more than two years. [15] Injuries usually result from stress on the hip joint as it rotates. Pain is mainly in the groin, but may also be in the trochanteric and hip areas.
• Mechanical Symptoms – Various mechanical symptoms have been reported, including clicking (most frequently) locking or getting stuck or giving up. The significance of these signs is questionable. [16]
• Range of motion: It is usually not restricted, but can cause pain in extreme cases.
  • These specific actions may cause groin pain:[9]
    • Hip flexion, adduction and internal rotation (FADDIR TEST) associated with anterosuperior tears
    • Passive hyperextension abduction and external rotation are associated with posterior tears

Differential Diagnosis

The differential diagnosis of a labral tear may include the following diagnoses:

• Athletic pubalgia
• Snapping_Hip
• Septic (Infectious) Arthritis
• Piriformis syndrome
• Contusion
• Strain
• Osteitis pubis
• Trochanteric Bursitis
• Avascular necrosis of the femoral head
• Fracture
• Dislocation
• Inguinal or femoral hernia
• Legg-Calve Perthes disease
• Slipped Capital Femoral Epiphysis
• Referral pain from the lumbosacral and sacroiliac regions
• Tumor[17]

Investigations

Plain radiographs and computed tomography may reveal dysplastic arthritis of the hip and acetabular cysts in patients with acetabular lip tears, and they help rule out other types of hip pathology. MRI is helpful in diagnosing an acetabular labral tear.

• MRA (Magnetic Resonance Arthrography) – yields the best results as gadolinium infusion is required intra-articularly or systemically to obtain the detail needed to study the labrum. The principle of the procedure relies on balloon dilation. Contour the labia with contrast and fill Any tears that may exist. MRA has limitations in its sensitivity for diagnosing abnormalities of the acetabular labrum and articular cartilage, and it has also been shown that MRA may be less effective in identifying posterior and lateral tears. [3]
• Diagnostic image-guided intra-articular hip injections – also helpful in diagnosing labral tears.
• Hip arthroscopy – used as the gold standard for diagnosis of ALT and as a therapeutic medium.

Conservative Management

Include relative resting anti-inflammatory and pain medication if necessary. Combined with a 10-12 week intensive physiotherapy program. The patient’s pain may decrease during this time, but the pain may return once the patient resumes normal activities. Surgical intervention may be considered when conservative treatment fails to control the patient’s symptoms. [18]

Outcome Measures

• Lower Extremity Functional Scale (LEFS)
• International Hip Outcome Tool (iHOT)

For more information, see Outcome Measures Database

Examination

Physical Examination

The test is considered positive if one or more of the following symptoms occur during the test: clicking or pain in the groin area. [18] [19]

• Impact Test – Passive hip flexion to 90° internal rotation and adduction (see video below).
• FABER Test – Passively place the lower body in a figure four position with light pressure on the inside of the knee. (7 of 18 tested positive)
• Resistance Straight Leg Raise Test – Patient’s hips flexed 30°, knees extended and downward pressure applied. (1 of 18 tested positive)
• McCarthy sign/Thomas test (hip flexion to extension movement) – The subject fully flexes both hips while the patient is in the supine position. The examiner slowly/passively extends the subject’s lower extremity and moves the hip into external rotation. Repeat the test, but with the hip in Pronation.
• Internal Rotation Load/Grind Test – With the patient in the supine position, the examiner passively flexes the patient’s hip to 100° and then rotates the subject’s hip from internal to external rotation while passing the knee along the femoral axis push to elicit “Grinding” (see video below).
• Fitzgerald Test – Used to assess the anterior labrum. The patient’s hip flexes sharply, then simultaneously extends with internal rotation and full abduction.
• Patrick’s Test – used to assess the posterior labrum. The patient’s hip flexes and then extends during abduction and external rotation.

[20]

Medical Management

Arthroscopy

The acetabular labral lesion can be repaired first in the supine or lateral position. In the supine position a stand fracture table with an oversized perinal post is used to apply traction. The affected hip is placed in slight extension/adduction to bring the joint closer together. In traction it is important to keep pressure low in the perineal area to avoid neurological complications. The procedure is under fluoroscopy guidance. Once the distraction is achieved a 14 or 16 gauge spinal needle is inserted into the joint to break the vacuum seal and allow further movement distractions. Three gates are used (anterolateral anterior and distal lateral accessory).For repair of a torn labrum, the margins of the tear are outlined and suture anchors are placed above the acetabular rim at the point of tear. If the tear in the labrum has a hard back rim and still attached to the acetabulum can be secured by a suture in the central element of the tear.[21]

Physical Therapy Management [21]

Movements that cause local stress should be avoided. The rehabilitation protocol following acetabular labral debridement or repair is divided into four phases.

Phase 1 – Initial Exercise (Week 1-4)

The primary goals after acetabularlabral debridement or repair are to reduce the pain and inflammation and to initiate movement exercises early. The beginning of this phase is an isometric contraction exercise for the hip adductors abductors transverse abdomen and extensor muscles. Labral debridement followed by closed chain activities such as the leg press or low shuttle may begin with minimal resistance. An assistive device for those with severe weight bearing pain. Strong movements within painful limits. Transversus abdominis and multifidus isolated contraction and light associated exercises such as bridge and kneeling close to the ground on hands and knees[22]

Weight bearing protocol after debridement is 50% for 7 to 10 days and non-weight bearing or toe-touch weight bearing for 3 to 6 weeks in case of labral repair. Unnecessary hypomobility will limit future progress so it is important to ensure that the patient remains normal transport and destination in this phase.

Treatment modalities:

• Aquatic therapy is an appropriate form of treatment – continuous aquatic activity allows for improved mobility by placing appropriate loads on the joints without placing unnecessary stress on the healing tissue. For example the patient can use flotation to do a light run in the water device. It is important to be aware of the patient’s mobilization precautions as these may vary during debridement or repair.
• Manual therapy to reduce pain and improve joint mobility and proprioception. Considerations include gentle hip joint mobilizations contract-relax stretching for internal and external rotation long axis distraction and assessment of lumbo-sacral mobility.
• Cryotherapy
• Appropriate pain management with medication.
• Gentle passive stretching of hip muscle groups including psoas quadriceps hamstring muscles.
• A stationary bike without resistance with seat height limited to less than 90° of hip
• Exercises like: Aqua Walking Piriformis Stretch Ankle Pump.

To enter Phase 2, ROM must be greater than or equal to 75%.

Phase 2 – Intermediate Practice (Weeks 5-7)

The goal of this phase is to continue to improve ROM and soft tissue flexibility. Manual therapy should continue to mobilize, i.e. more active passive ROM exercises should become more active as needed for external and internal rotation. Stop using assistive devices.

• Flexibility exercises involving the piriformis adductor group psoas/rectus femoris should continue
• Stationary bike with resistance
• Maitland Manual Mobilization (Levels 3 and 4) and Combinations
• Pelvic rotation maneuver
• Sacroiliac distraction
• Sidestepping with abductor band for resistance
• Core strength (lumbopelvic stabilization exercises combined with moderate exercises like lateral bridge and mini squat and light sensory muscle training);
• Non-competitive swimming
• Exercises, such as sitting against a wall, with abductor bands bridging the legs
• Standing hip flexion and extension (progressive load) 3 x 10 reps Standing hip abduction and adduction with elastic resistance near a support bar (progressive load) 3 x 10 reps Lunge (progressive load) 3 × 10 reps • Shuttle (progressive load) 3 × 10 70% MR repetitions • Knee extension on chair (progressive load) 3 × 10 repetitions 70% MR • Side step gait, elastic band on midfoot 3 × 1 min • Dynamic valgus control, single-limb squat 3 × 1 minute[22]
• Improving Balance • Balance • Balance Board • DynaDisc • Springboard [22]

To progress to stage 3, it is important that the patient has a normal gait pattern and no Trendelenburg signs. Patients should have symmetrical and passive ROM measurements with minimal complaints of pain.

Phase 3 – Advanced Exercise (Week 8-12)

• Manual therapy should be performed as needed
• If limitations persist, flexibility and passive ROM interventions should become more aggressive (if the patient has reached his full ROM or flexibility terminal stretches should begin)
• Strengthening exercises: Walking lunges, torso rotations, walking forward/backwards in water with resistance exercise cables, enhanced bounces. Maintain muscle strength (progressive loading) and address any persistent muscle imbalances.
• Core (lumbopelvic stabilization exercises) combined with Swiss ball exercises and advanced sensorimotor training
• Exercises such as core ball stability golf progression lunges

To move into stage 4, it is important to have symmetrical ROM and flexibility of the psoas and piriformis.

Phase 4 – Sport Specific Training (Week 12 -*)

During this phase, it is important to safely and efficiently return to play or previous activity levels. Manual therapy dexterity and ROM exercises may continue as appropriate.

It is important that the patient has good muscular endurance, good eccentric muscle control and the ability to generate force.

Patients can be exercised for specific movements and must be able to demonstrate good neuromuscular control of the lower extremities during activities.

Exercises such as: Sports-specific training functional testing

Key Research

• Greaves LL et al. Effect of acetabular lip tear repair and resection on hip cartilage strain: a 7T MR study. J Biomechanics. 2010 Mar 22;43(5):858-63. doi: 10.1016/j.jbiomech.2009.11.016. http://www.jbiomech.com/article/S0021-9290(09)00652-6/abstract (accessed January 27, 2014)
• Springer BA et al. Acetabular labral tears: diagnostic accuracy of clinical examination by physiotherapists, orthopedic surgeons, and orthopedic residents. N Am J Sports Phys Ther. 2009 Feb;4(1):38-45. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953315/pdf/najspt-04-038.pdf (accessed Jan. 27 2014）。
• Nishii T et al. Acetabular labral tear: contrast-enhanced MR imaging under continuous leg distraction. Skeletal Radiology. 1996 May;25(4):349-56.