T-Capsulotomy
Pericapsular fatty tissue is débrided with an arthroscopic shaver to visualize the interval between the iliocapsularis and gluteus minimus muscles. An arthroscopic scalpel is used, through a 5.0-mm cannula in the DALA portal, to extend the capsulotomy longitudinally and perpendicular to the interportal capsulotomy (Figure 1C). The T-capsulotomy is performed along the length of the femoral neck distally to the capsular reflection at the intertrochanteric line. The arthroscopic burr is used to perform a femoral osteochondroplasty between the lateral synovial folds (12 o’clock) and the medial synovial folds (6 o’clock). Dynamic examination and fluoroscopic imaging confirm that the entire cam deformity has been excised and that there is no evidence of impingement.
Although various suture-shuttling or tissue-penetrating/retrieving devices may be used, we recommend whichever device is appropriate for closing the capsule in its entirety. With the arthroscope in the modified anterior portal, an 8.25-mm × 90-mm cannula is placed in the AL portal, and an 8.25-mm × 110-mm cannula in the DALA portal. These portals will facilitate suture passage.
The vertical limb of the T-capsulotomy is closed with 2 to 4 side-to-side sutures, and the interportal capsulotomy limb with 2 or 3 sutures. Capsular closure begins with the distal portion of the longitudinal limb at the base of the iliofemoral ligament (IFL). A crescent tissue penetrating device (Slingshot; Stryker Sports Medicine) is loaded with high-strength No. 2 suture (Zipline; Stryker Sports Medicine) and placed through the AL portal to sharply pierce the lateral leaflet of the IFL (Figure 1D). The No. 2 suture is shuttled into the intra-articular side of the capsule (Figure 1E). Through the DALA portal, the penetrating device is used to pierce the medial leaflet to retrieve the free suture (Figure 1F). Next, the looped suture retriever is used to pull the suture from the AL portal to the DALA portal so the suture can be tied. We prefer to tie each suture individually after it is passed, but all of the sutures can be passed first, and then tied. As successive suture placement and knot tying inherently tighten the capsule, successive visualization requires more precision. Each subsequent suture is similarly passed, about 1 cm proximal to the previous stitch.
After closure of the vertical limb of the T-capsulotomy, we prefer to close the interportal capsulotomy with the InJector II Capsule Restoration System (Stryker Sports Medicine), a device that allows for closure through a single cannula lateral to medial. This device is passed through the AL cannula in order to bring the suture end through the proximal IFL attached to the acetabulum (Figure 1G). The device is removed from the cannula, and the other suture end is placed in the device and passed through the distal IFL (Figure 1H). The stitch is then tensioned and tied. Likewise, closure of the medial IFL involves passing the InJector through the DALA cannula and bringing the first suture end through the proximal IFL attached to the acetabulum. The Injector is removed from the cannula, and the other suture end is placed in the device and passed through the distal IFL. The stitch is then tensioned and tied with the hip in neutral extension. Generally, 2 or 3 stitches are used to close the interportal capsulotomy. Complete capsular closure is confirmed by the inability to visualize the underlying femoral head/neck and by probing the anterior capsule to ensure proper tension (Figure 1I).
Extensile Interportal Capsulotomy
An alternative to T-capsulotomy is interportal capsulotomy. Just as with T-capsulotomy closure, multiple different suture passing devices can be used. Good visualization for accessing the peripheral compartment generally is achieved by making the interportal capsulotomy 4 cm to 6 cm longer than the horizontal limb of the T-capsulotomy (Figures 2A, 2B). Capsular closure usually begins with the medial portion of the interportal capsulotomy. With the arthroscope in the AL portal, the 8.25-mm × 90-mm cannula is placed in the midanterior portal (MAP), and an 8.25-mm × 110-mm cannula is placed in the DALA portal.
Through the MAP, the crescent tissue penetrating device (Slingshot) is used to sharply pierce the proximal leaflet, and high-strength No. 2 suture is passed into the intra-articular side of the capsule (Figure 2C). The penetrating device is then used to pierce the distal leaflet to retrieve the free suture (Figure 2D), and the suture ends are clamped with a hemostat outside the hip for closure at the end of the case (Figure 2E). The steps are repeated until the capsulotomy is entirely closed; 3 to 5 sutures may be involved. For interportal capsulotomy closure, we prefer to pass all sutures before tying in order to facilitate visualization as each successive suture is passed. The lateral-most set of sutures can be retrieved with a looped suture retriever through the DALA portal (Figure 2F) and can be tensioned and tied using arthroscopic techniques (Figure 2G).