Principles of Hip Arthroscopy

 

 

Preoperative Preparation

 

Thromboembolic deterrent (TED) stockings are placed on both lower extremities 2 in below the level of the fibular head to avoid compression of the peroneal nerve. Hair on the operative extremity is trimmed medially to 1 in medial to the anterior superior iliac spine (ASIS), posterolaterally to the midbuttock, proximally to 2 i proximal to the inguinal crease and distally to 6-8 in distal to the inguinal crease.

All preoperative imaging studies (XR, CT, and/or MRI) should be available fo viewing in the OR.

 

Anesthesia

Before surgery, the anesthesia plan is discussed with the appropriate anesthesia provider.

 

Endotracheal intubation rather than a laryngeal mask airway is recommended. Muscular paralysis is induced.

The goal is systolic blood pressure of ~100 mm Hg.

 

Patient Positioning, Fluoroscopy, Traction, and Draping

Hip arthroscopy can be done with the patient in a supine or lateral position. We prefer supine positioning using a commercially available fracture table or table extension to provide traction.

On the contralateral (non-operative) extremity, large pads are placed on the heel

and dorsal and plantar aspects of the foot. On the operative extremity, a single pad is placed on the dorsal foot, and the foot and ankle are wrapped with self-adherent (Coban, 3M, St. Paul, MN) wrap to prevent slippage in the boot.

Both feet are placed in the traction boots so that the heels are all the way down in the boot. The boot is closed as tightly as possible and secured with cloth tape.

The patient is positioned so the operative extremity is against a well padded perineal post and then distally, so that the perineum abuts the post as well.

The nonoperative extremity is abducted to 45 to 60 degrees and the operative extremity to 10 degrees. Both extremities should be placed in neutral rotation (patella facing ceiling) and alignment in the sagittal plane (no flexion or extension). Some surgeons prefer 15-20 degrees of internal rotation to place the femoral neck parallel to the ground and 10-20 degrees of hip flexion (Fig. 30-1).

 

Figure 30-1 Patient positioned supine for right hip arthroscopy. Note the perineal post is lateralized toward the operative hip. The operative hip is positioned in 10 degrees of abduction, as well as neutral rotation and neutral flexion/extension. The nonoperative hip is abducted 45-60 degrees to allow the fluoroscopic monitor to be positioned to assist with the surgery.

 

A clear nonsterile U-drape is placed from inferior to superior, on the far side of

the umbilicus, medial to the ASIS, and as far posteriorly along the buttock as possible, and a clear nonsterile sheet is placed transversely at the level of the umbilicus.

The fluoroscopy machine should come between the patient)s legs.

Traction with just body weight is placed on the nonoperative extremity to help lateralize the operative extremity. Gross traction is placed on the operative extremity, followed by fine traction to subluxate the hip (usually10 to 50 lb of traction for 8-10 mm of hip joint distraction).

 

Approach and Arthroscopic Portals

The anatomic structures are not outlined and no arthroscopic portals are made until traction is applied (Fig. 30-2).

 

Figure 30-2 Right hip with surgical marker outlining the greater trochanter, ASIS, and #1 intersection of line going distal from ASIS and line going transverse at the tip of the greater trochanter, #2 anterior portal, #3 anterolateral portal, #4 posterolateral portal, #5 modified anterior or mid-anterior portal, #6 distal anterolateral portal, and #7 distal portal for endoscopic iliopsoas lengthening at the lesser

trochanter.

 

With standard sterile technique, an 18-gauge spinal needle is inserted at the site of the anterolateral portal (see below). The spinal needle should enter the hip joint between the femoral head and labrum (with the bevel facing away from the femoral head and the shaft adjacent to the femoral head) with a trajectory slightly convergent with the femoral neck and aiming toward the superior cotyloid fossa and medial sourcil (Fig. 30-3A).

 

 

Figure 30-3 A. Fluoroscopic image of 18-gauge spinal needle entering at the site of the anterolateral portal with a trajectory slightly convergent with the femoral neck and aiming toward the superior cotyloid fossa and medial sourcil. B. Fluoroscopic image following spinal needle stylet removal showing air arthrogram that confirms intra-articular access has been achieved with the spinal needle.

 

Once the spinal needle tip is intra-articular, the stylet is removed to eliminate the negative intra-articular pressure. Upon removal of the stylet, the quadriceps muscle will relax, indicating capsular and proprioceptive mechanoreceptor relaxation. Fluoroscopy should confirm intra-articular access with an air arthrogram (Fig. 30-3B).

The amount of traction necessary is recorded, and then, traction is released for

preparation and draping to reduce unnecessary traction time. After traction is released, an additional fluoroscopic image is taken to confirm that the hip is fully reduced or if there is residual subluxation.

The operative field is prepared and draped according to the surgeon)s preference, taking care to ensure that a wide surgical field is maintained from medial to the ASIS to the midbuttock laterally and from just distal to the umbilicus to the dista thigh (Fig. 30-4).

 

Figure 30-4 Sterile draping of operative field for right hip arthroscopy.

 

Anterolateral Portal

Location: 1-2 cm proximal and anterior to the tip of the greater trochanter. Trajectory for spinal needle localization is ~15 degrees cephalad and 20-30 degrees posteriorly.

Uses: central compartment viewing (particularly anteriorly and superiorly) and working (eg, debridement, anchor placement), peripheral compartment viewing and working (Fig. 30-5)

Figure 30-5 Arthroscopic image with a 70-degree arthroscope through the anterolateral portal showing the anterosuperior labrum on the left, the femoral head on the right, and capsule straight up, between the femoral head and labrum (V shaped).

 

Risks: iatrogenic chondral and/or labral injury, superior gluteal nerve injury

 

Anterior Portal

Location: 1-2 cm lateral to intersection of line going distal from ASIS and line going transverse at the tip of the greater trochanter. Trajectory for spinal needle localization is ~40-45 degrees cephalad and 25-30 toward the midline.

Uses: central compartment viewing and working (labral takedown, retraction, and debridement) (Fig. 30-6)

Figure 30-6 Arthroscopic image with a 70-degree arthroscope through the anterior portal looking posteriorly showing the acetabular cartilage and labrum on the left, the femoral head on the right, and the anterolateral and posterolateral cannulas.

 

Risks: lateral femoral cutaneous nerve injury (a knife is used to cut skin only and not deeper)

 

Modified/Mid-Anterior Portal

Location: 4-6 cm anterior and distal to anterolateral portal. Trajectory for spinal needle localization is ~30 degrees posterior and 30 degrees superior.

Uses: central compartment viewing and working (labral takedown and debridement), anchor placement (especially anterior and anterolateral acetabulum)

 

Distal Anterolateral Portal

Location: 3-5 cm distal to anterolateral portal

Uses: anchor placement (especially lateral and posterolateral acetabulum), peripheral compartment work

 

Proximal Anterolateral Portal

 

Location: 3-4 cm proximal and slightly posterior to anterolateral portal Uses: peripheral compartment work

 

Posterolateral Portal

 

Location: 1 cm posterior to the superior-posterior tip of the greater trochanter Uses: central compartment viewing, posterior labral repair (Fig. 30-7)

 

 

Figure 30-7 A. Arthroscopic image with a 70-degree arthroscope through the posterolateral portal showing the cotyloid fossa on the left and the femoral head with chondral flap on the right. B. Arthroscopic image with a 70-degree arthroscope through the posterolateral portal showing the arthroscopic probe entering the mid-anterior portal, an acetabular articular cartilage defect on the left with the intact labrum above it, and the femoral head on the right.

 

Risks: sciatic nerve injury (portal is placed with hip in neutral rotation), deep branch of medial femoral circumflex artery injury

 

Indications for Hip Arthroscopy

·Femoroacetabular impingement (pincer, cam, subspine, ischiofemoral, combined

·type)

·Labral pathology Chondral pathology Ligamentum teres injuries Iliopsoas pathology

·Hip instability or capsular laxity or insufficiency Snapping hip (internal or external)

·Loose bodies or heterotopic ossification Synovial disorders

·Septic arthritis

·Gluteus medius and/or minimus repair Peritrochanteric conditions

·Proximal hamstring repair Expanding indications

·Acetabular rim fractures Femoral head fractures

·In conjunction with treatment of osteonecrosis Sciatic nerve endoscopy/deep gluteal space

Diagnostic Arthroscopy

 

Femoral head and acetabular articular cartilage Labrum

 

Ligamentum teres/cotyloid fossa Capsule

 

Postoperative Protocols

20 lb foot flat weight bearing with crutches is allowed for 2 weeks after chielectomy/femoral head osteoplasty. An additional week is used per decade for women over 39 years of age, and men over 49 years of age. An abduction brace is used if there is a concomitant labral repair and/or capsular plication. Crutches are used for 6 weeks if microfracture was done.

Naproxen 500 mg PO bid is given for 4 weeks for heterotopic ossification prophylaxis (as well as for pain control and to reduce the risk of deep venous thrombosis).