Current Concepts With Video Illustrations Capsular Management During Hip Arthroscopy: From Femoroacetabular Impingement to Instability Asheesh Bedi, M.D., Gregory Galano, M.D., Christopher Walsh, M.D., and Bryan T. Kelly, M.D. Abstract: Advances in the ability to treat various soft-tissue and osseous pathologic conditions of the hip arthroscopically have been predicated on an improved exposure of the pathology of the central, peripheral, and peritrochanteric compartments. The management of the capsule is critical and must allow for an improved exposure without compromising stability and kinematics of the hip. Described approaches have included capsulectomy, limited capsulotomy, extensile capsulotomy, capsular plication, and capsular shift. The selected approach must consider various factors, including symp- tomatic complaints, underlying hyperlaxity, specific mechanical pathology, and surgical expertise. Universally using a single technique without consideration of the complex mechanical and anatomic factors unique to each patient may result in incomplete treatment of the pathoanatomy or iatrogenic instability. This article reviews the anatomy of the hip capsule and provide a diagnosis-based consideration of capsular management during hip arthroscopy. The senior author’s preferred tech- niques are also presented. ip arthroscopy has gained considerable popu- ity to treat various soft-tissue and osseous pathologic Hlarity in recent years as a minimally invasive conditions of the hip arthroscopically have been pred- surgical approach to address various symptomatic icated on an improved exposure of the pathology of disorders of the hip, including femoroacetabular the central, peripheral, and peritrochanteric compart- impingement (FAI), labral tears, snapping hip syn- ments. In this regard, surgical management of the dromes, and instability. As such, there has been a capsule is critical and must allow an improved expo- rapid evolution of both instrumentation and tech- sure without compromised stability of the hip (Table niques used in hip arthroscopy. Advances in the abil- 1). Described approaches have included capsulec- tomy, limited capsulotomy, extensile capsulotomy, capsular plication, and capsular shift. The selected approach must consider various factors, including From MedSport, Division of Sports Medicine and Shoulder Surgery, University of Michigan (A.B., C.W.), Ann Arbor, Michi- symptomatic complaints, baseline hyperlaxity, spe- gan; and the Center for Hip Pain and Preservation, Hospital for cific mechanical pathology, and surgical expertise. Special Surgery (G.G., B.T.K.), New York, New York, U.S.A. Universally using a single technique without con- The authors report no conflict of interest. Received July 18, 2011; accepted August 9, 2011. sideration of the complex mechanical and anatomic Address correspondence to Asheesh Bedi, M.D., MedSport, Uni- factors unique to each patient may result in incom- versity of Michigan, 24 Frank Lloyd Wright Dr, Lobby A, Ann plete treatment of the pathoanatomy or iatrogenic Arbor, MI 48106, U.S.A. E-mail: [email protected] © 2011 by the Arthroscopy Association of North America instability. This article will review the anatomy of 0749-8063/11459/$36.00 the hip capsule and provide a diagnosis-based con- doi:10.1016/j.arthro.2011.08.288 sideration of capsular management during hip ar- Note: To access the videos accompanying this report, visit the throscopy. The senior author’s preferred techniques December issue of Arthroscopy at www.arthroscopyjournal.org. are also presented. 1720 Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 27, No 12 (December), 2011: pp 1720-1731 CAPSULAR MANAGEMENT DURING HIP ARTHROSCOPY 1721 TABLE 1. Key Points The management of the capsule is critical and must allow for an improved exposure without compromising stability and kinematics of the hip. Universally using a single technique may result in incomplete treatment of FAI or iatrogenic instability. Preservation or repair of the iliofemoral ligament is critical during hip arthroscopy, particularly for patients with hyperlaxity, anterior instability, and/or dysplasia. The zona orbicularis provides hip stability against distraction forces, acting like a locking ring around the neck of the femur. The medial femoral circumflex artery is the main vascular supply of the femoral head. The blood supply of the femoral head therefore arises near the femoral attachment of the capsule and can sustain damage in overzealous, distal transverse capsulotomies. The indirect head of the rectus tendon can be visualized through an interportal capsulotomy and is a very important arthroscopic landmark to guide rim resection, anchor placement, and labral repair. Arthroscopic visualization in the peripheral compartment is critical to guide placement of an ideal T-capsular incision in the intermuscular plane between the inserting fibers of the gluteus minimus and iliocapsularis. If the plane for T-capsulotomy is accurately identified, the medial capsule translates medially from the pull of the iliocapsularis, and the lateral capsule translates laterally from the gluteus minimus to facilitate separation of the 2 limbs of the iliofemoral ligament. The T-capsulotomy should stop proximal to the zona orbicularis to avoid injury to the terminal branch of the lateral femoral circumflex artery. The T-capsulotomy provides an excellent view of the head-neck junction as distal as the intertrochanteric line and allows for circumferential restoration of femoral offset. It is reparable with side-to-side stitches to restore joint anatomy and stability. Overzealous capsulotomy without repair or capsulectomy can result in iatrogenic hip instability after arthroscopy. CAPSULAR ANATOMY LIGAMENTS The hip capsule is a fibrous lining that provides Iliofemoral Ligament stability, protection, and the blood supply for the hip The iliofemoral ligament (Y ligament of Bigelow) joint. From its acetabular attachment, it extends later- makes up the anterior part of the capsule and is shaped ally to surround the femoral head and neck and is like an inverted “Y.” It originates in the area between attached anteriorly to the intertrochanteric line, supe- the anteroinferior iliac spine (AIIS) and acetabular rim riorly to the base of the femoral neck, posteriorly and divides into superior and inferior branches as it superomedial to the intertrochanteric crest, and in- crosses the joint.2,5 The superior-lateral branch has a feriorly to the femoral neck near the lesser trochan- horizontal course and inserts proximally along the 1 ter. The anterosuperior portion of the capsule is intertrochanteric line anterior to the hip joint, whereas thickest, because this is where maximal stress oc- the inferior-medial branch has a more vertical course curs while one is standing, whereas the posteroin- and inserts distally along the intertrochanteric line ferior capsule is thinner and more loosely attached. (Fig 1).4 The action of the iliofemoral ligament restricts The thick anterosuperior capsule often needs to be extension of the hip, providing a static restraint with full addressed with arthroscopy for FAI, because this is hip extension, and allows upright posture to be main- a typical location for focal rim impingement and tained without constant muscular action.2,6 Hewitt et loss of femoral offset. al.5,6 showed that the iliofemoral ligament is stiffer and The capsule is composed of internal and external withstands greater force than either the ischiofemoral fibers. The internal fibers comprise the circular zona ligament or the pubofemoral ligament, suggesting that its orbicularis, which forms a collar around the femoral insufficiency is associated with anterior hip instability neck.2,3 The fibers of the zona orbicularis are partially and dislocations. In this regard, preservation or repair of blended with fibers from the ischiofemoral ligament.4 the iliofemoral ligament may be of critical importance The internal fibers of the capsule are lined with syno- during hip arthroscopy, particularly for patients with vium and contact the femoral head. The external fibers hyperlaxity, anterior instability, and/or anterior acetabu- run longitudinally and are made up of the iliofemoral, lar undercoverage (dysplasia). ischiofemoral, and pubofemoral ligaments.1,4 Each of Martin et al.4 recently studied the anatomy and these ligaments has distinct functions that are impor- quantitative contributions of the hip capsular liga- tant to the capsule (Fig 1). ments. The medial arm of the iliofemoral ligament was 1722 A. BEDI ET AL. FIGURE 1. (A) Anteroposterior view of hip showing ilio- femoral and pubofemoral ligament. The capsular insertion distally to the intertrochanteric line should be noted. (B) Posterior view of hip showing ischiofemoral ligament and relation to obturator externus tendon. (Reprinted with per- mission from Wesley Norman, Ph.D.) observed to originate between the AIIS and the iliac along the intertrochanteric crest (Fig 2).4 The main portion of the acetabular rim. Its insertion was consis- action of the ischiofemoral ligament is to resist inter- tently noted to be on a bump located on the distal nal rotation as well as adduction.2,4,6 The ischiofem- intertrochanteric line (Fig 2). The lateral arm originates oral ligament is significantly weaker than the iliofem- superior to the medial arm, closer to the AIIS, and oral ligament, with either the superior or inferior half traverses more horizontally along the neck of the femur, of the iliofemoral ligament being stronger than the