HIP ARTHROSCOPY

Written by Michael W. Tanner, M.D.
November 2007

ANATOMY OF THE HIP JOINT

The hip joint is a constrained ball and socket joint. The ball is termed the femoral head, and the socket is called the acetabulum. The edge of the acetabulum has a thick cartilage called the acetabular labrum. Technically, this is termed a triangular fibrocartilage that enhances the joint stability. The white coating on the femoral head and acetabulum surface is called articular cartilage. The joint is incased and stabilized by a thick capsule of ligaments. The interior of the hip capsule has a coating called synovium that makes the joint fluid. There are 27 muscles that cross the hip joint that control the movement and propel our bodies.

Figure 1	Figure 2	Figure 3

SYMPTOMS ASSOCIATED WITH HIP JOINT PROBLEMS

• Groin and lateral pain.
• Catching sensation.
• Loss of movement of the hip.
• Pain with rising from a seated position.
• Pain when getting in and out of a car.
• Pinching sensation with prolonged sitting.
• Pain and catching with twisting movements.
• Limping.

CONSERVATIVE TREATMENT MODALITIES FOR HIP CONDITIONS

As with many medical problems, nonsurgical treatment should be instituted and considered as the first line of treatment. Common treatment modalities for hip conditions are rest, ice, nonsteroidal anti-inflammatory medication, and physical therapy.

HIP PROBLEMS THAT CAN BE TREATED WITH ARTHROSCOPY

1. Acetabular labrum tears.
2. Loose bodies.
3. Articular cartilage defects.
4. Ligamentum teres tears.
5. Bone growths causing impingement.
6. Snapping tendons.
7. Bursitis.
8. Gluteus medius tears.
9. Synovial disease and growths.
10. Early degenerative arthritis with mechanical symptoms.

DETAILS

1. Acetabular labrum tears: Acetabular labrum tears involve the rubber cartilage at the edge of the socket. Labrum tears are a result of twisting and falling injuries.

   Figure 4		Simple Anterior Labrum Tear

   Long-standing tears can be the result of impingement (see femeroacetabular impingement below). Long standing untreated tears can progress and result in articular cartilage damage at the margin adjacent to the labrum cartilage. This is referred to as the “watershed lesion.” Arthroscopic surgery can be performed to trim the torn portion of the labrum. In selected circumstances, we perform a suturing repair of the detached portion of the labrum.

   Before Repair	After Repair

2. Loose bodies: Loose fragments of articular cartilage can cause pain and a catching sensation. They can become trapped or float free. These types of conditions can result from a fall onto the hip.

   Loose Fragment After Hip Dislocation

3. Articular cartilage defects: The articular cartilage of the femoral head or acetabulum can split, bubble, or peel. Trimming of the loose fragments is called chondroplasty.

4. Ligamentum teres tears: Dislocation for the hip can cause a tear of the deep ligament that secures the femoral head. The stump of the torn ligament can cause irritation of the joint.

   Ligamentum teres tears, Before Repair	After Repair

5. Bone growths causing impingement: Excess bone growth can occur as an extra lip on the socket. This bone growth pinches against the femoral head and labrum. An extra bump on the femoral head causes a deviation from the normal sphericity of the femoral head. This leads to increased friction and damage of the acetabular rim cartilage. The condition that results has been termed femoroacetabular impingement (FAI).

6. Snapping tendons: Tendons can become sticky and irritated when they rub over a prominent bone surface. At the hip, the iliopsoas (hip flexor) and tensor fascia (abduction) tendons can be felt as a snapping and painful condition. Arthroscopic surgery for these conditions consists of release of the tight sticky tendon and resection of the extra lip or spur of bone.

7. Bursitis: A lubricating pocket around a bone surface and tendon is called a bursa. Bursitis is the result of inflammation and irritation of these structures. Arthroscopic resection can relieve cases of recalcitrant chronic bursitis that is not relieved with conservative measures.

8. Gluteus medius tears. The gluteus medius attaches to the greater trochanter. This tendon can be likened to the rotator cuff tendon of the shoulder. The gluteus medius tendon can tear and cause pain at the lateral hip as well as weakness and limping. Arthroscopic repair and suturing of this tendon shows great promise for relief of symptoms.

9. Synovial disease and growths: The synovium of the hip join is the lining tissue that produces joint lubricating fluid. Disease of this tissue can produce growths that are painful, limit motion, and cause limping. Arthroscopic biopsy and resection of the synovial disease can produce good relief of these symptoms.

10. Degenerative arthritis. Arthroscopic surgery is performed for mild to moderate osteoarthritis. The procedure can relieve mechanical symptoms consisting of catching and locking, loose fragments, and synovitis can act as mechanical irritants of the joint.

DIAGNOSIS OF HIP PROBLEMS

Hip pain can be a diagnostic challenge. Simply stated, many problems of the hip can be difficult to evaluate and treat. Additional problems that can cause hip pain are bursitis, tendonitis, and lumbar disk problems that cause nerve pain (sciatica).

DIAGNOSTIC STUDIES

1. X-ray.

   • X-rays are standard radiographs that can demonstrate bone irregularity, arthritic changes, and can demonstrate narrowing of the cartilage space of the hip joint.

2. CT scan.

   • A CT scan can give detail on bone growths and calcified loose bodies of the hip joint.

3. MRI.

   • This study is best for soft tissue growths or damage. For example, tendon and labrum tears can be viewed on an MRI scan. One condition of the hip that can be diagnosed with MRI scan is osteonecrosis. Another term for this is avascular necrosis of the femoral head. The MRI has limitations in the diagnosis of articular cartilage problems.

4. MR arthrogram.

   • This is an injection test in which special dye acts as a silhouette. This type of testing can help diagnose labrum tears.

5. Diagnostic injections.

   • Injections of local anesthetic and steroid can be preformed under fluoroscopic control in which there may be a need to clarify the exact sources of pin in a hip condition.

DETAILS OF ARTHROSCOPIC SURGERY OF THE HIP

This procedure is performed under general anesthesia. Traction is used to distract the hip cartilage surfaces. This is performed under fluoroscopic (portable x-ray) control. The surgery is performed through a system of sleeves with the use of the two to four one centimeter incisions.

AFTER CARE

A patient will need to be at bedrest for three to five days. Crutches are used for approximately seven to ten days in uncomplicated cases. In patient’s requiring repairs or who have extensive problems, crutches may be necessary for four to six weeks. Ice is important for the first week after surgery. Ice machines or cryotherapy are popular methods of applying cold to the hip joint. A patient may use the bathroom immediately after surgery. Dressings are used for two days, and then Band-Aids are used at the small incision sites. A patient may shower the following day, and the product Press’n Seal can be helpful to keep p the dressings dry. Analgesic pain medication will be necessary for the first few days.

Physical Therapy: Simple home exercises are performed for the first two weeks consisting of passive movement and isometrics. Physical therapy at an outpatient center starts at approximately two weeks after surgery and may continue for four to eight weeks.

Recovery parameters for typical, uncomplicated conditions:

• Driving with the right leg involved can resume at ten to 14 days postoperatively.
• Walking one block or more may begin at two to three weeks after surgery.
• Shopping can begin at two to three weeks postoperatively.
• Bicycling at two to three weeks postoperatively.
• Walking for exercise at four weeks after surgery.
• Pool exercise can begin ten days after surgery.
• Twisting, golf, and lifting can resume at two months postoperatively.
• Running may begin at three months after surgery.

COMPLICATIONS OF HIP ARTHROSCOPY

• Nerve irritation is a distant possibility.
• Deep vein thrombosis or blood clots have been reported and are an unusual complication.
• Chondral scuffing.
• Chronic pain and progression of arthritis change.

COMMENTS ON REHABILITATION AND AFTER CARE

Anti-inflammatory medication may be used to prevent deep vein thrombosis and to decrease a calcification reaction at the join. These medications can be used to help decrease pain.

Notes on early rehabilitation measures:

1. Early phase (zero to two weeks): Pendulum type exercise. Passive motion consists of flexion, abduction, external rotation in flexion, and internal rotation in extension. Isometrics are encouraged, except for hip flexion.
   • Avoid:
   • Hip flexor activation in the first two weeks.
   • Lying prone (face down).
   • Full weight on leg. Use crutches with toe touch (15-30 pounds pressure) as directed by the physician.
2. Midphase (two to four weeks): May start active hip flexion. We encourage low or no resistance exercise bicycle (avoids the use of cleats or toe straps). A brace may be used in the early and midphases to control hip motion. A continuous passive motion (CPM) machine may be used in the early and midphases, especially if there has been microfracture chondroplasty of an articular surface. Crutches will be discontinued at the late phase if there has been a labral repair or microfracture chondroplasty.
3. Late Phase recovery (after four weeks): Progressive motion and strengthening, often under the direction of a physical therapist.