4 Varus Thrust and Osteotomies to Treat Posterolateral Knee Injuries Markus Arnold MD, PhD

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1 Agenda for ISAKOS 2011 Posterolateral Knee Symposium May 19, 2011 (one hour) The posterolateral knee symposium agenda will cover current topics related to global diagnosis and recognition and cutting edge treatment of this difficult pathology. Each faculty will be allotted seven (7) minutes to cover their topic. Please be respectful of other faculty and adhere to this time frame because we cannot exceed this time frame for our symposium. Symposium Goals: It is anticipated that participants will have an improved ability to understand the complex anatomy, clinically relevant biomechanics, diagnostic techniques, and operative treatment of both acute and chronic posterolateral knee injuries from attending this course. Chair: Robert F. LaPrade MD, PhD Agenda: 1 Clinically Relevant Anatomy and Diagnostic Techniques Rob LaPrade MD, PhD 2 Clinically Relevant Biomechanics Coen Wijdicks, PhD 3 Treatment of Acute Posterolateral Knee Injuries Andrew Geeslin, MD 4 Varus Thrust and Osteotomies to Treat Posterolateral Knee Injuries Markus Arnold MD, PhD 5 Indications for Surgery and Presence/Treatment of Concurrent Injuries Roland Becker MD, PhD 6 Techniques for Treatment of Chronic Posterolateral Knee Injuries Anatomic Allograft Steinar Johansen, MD 7 Techniques for Treatment of Chronic Posterolateral Knee Injuries Anatomic Autograft Rene Abdalla MD, PhD 8 Questions from Audience All Panelists E mail: drlaprade@sprivail.org

2 2/22/2011 Clinically Relevant Anatomy and Diagnostic Techniques for Posterolateral Knee Injuries ISAKOS Symposium Rio de Janeiro, Brazil May 19, 2011 Robert F. LaPrade, M.D., Ph.D. Director, Biomechanics Research Department, Steadman Philippon Research Institute; The Steadman Clinic - Vail, Colorado, USA Applied Anatomy of the Posterolateral Knee * 28 different individual components Fibular Collateral Ligament (LaPrade, AJSM, 2003) 1 varus stabilizer Attachment sites: Proximal / posterior to lateral epicondyle Midway along fibular head 1

3 2/22/2011 Popliteus Tendon Important stabilizer to posterolateral rotation Popliteus attachment on femur 18.5 mm from FCL attachment on femur attaches to anterior fifth of popliteal sulcus Popliteofibular Ligament Originates at musculotendinous junction Anterior / Posterior divisions Static stabilizer of ER Arcuate ( Arched ) Ligament Does not exist Misnamed in literature PFL vs. fibular structures 2

4 2/22/2011 History Usually due to varus or hyperextension twisting injuries Majority (72%) are combined ligamentous injuries (LaPrade, AJSM, 1997; Geeslin, AJSM, 2011) Diagnosis of Posterolateral Knee Injuries Acute vs chronic; isolated vs combined injuries Multiple tests needed to assess PLC injury Remember to test for peroneal nerve function Injured in 15% of posterolateral knee injuries (LaPrade,1997) External Rotation Recurvatum Test (Hughston, 1980) Lift big toe Assess recurvatum I di ti f bi d lig t i j Indicative of combined ligament injury (usually ACL tear) LaPrade, AJSM

5 2/22/2011 Varus stress test at 30 (Hughston, 1966) Put fingers over joint line Apply stress through foot/ankle, not the leg Check contralateral knee Posterolateral Drawer Test (Hughston, 1980) Knee flexed to 90 Foot 15 ER (sit on foot) Assess posterolateral rotation Check contralateral normal knee Dial Test at 30 and 90 External rotation of tibial tubercle increase at 30 (Grood, 1988; Fanelli,1998) If increases at 90, PCL (Grood, 1988) and/or ACL (Wroble, 1993) also injured * beware of disguised medial knee injuries 4

6 2/22/2011 Reverse Pivot Shift Test (Jakob, 1981) Opposite of pivot shift Knee flexed, foot ER Extend knee to reduce subluxed tibia * Dynamic Posterolateral Drawer Test Popliteus tendon main stabilizer Large variability 35% in normal knees (Cooper, 1991) Anterior Translation at 30 Sectioning PLC - no increase in primary anterior translation In ACLD knees, absent PLC results in increased translation 0-30 (grade 3+) (Nielsen 1986; Wroble 1993) * think combined PLC for 3+ Lachman Posterior Translation at 90 PCL - main restraint: 8 mm PT (grade 2) Combined PCL/PLT: >12 mm PT (grade 3) * think combined PLC for 3+ posterior drawer 5

7 2/22/2011 Varus Thrust Gait Usually underlying varus alignment May adapt with flexed knee gait Avulsion Fractures Arcuate avulsion Segond avulsion * MRI defines attached structures better than Xrays Varus Stress Xrays (LaPrade, JBJS, 2008) Side to side difference >2.7 mm complete FCL tear >4 mm complete PLC tear 6

8 2/22/2011 Kneeling PCL Stress Xrays (LaPrade, AJSM, 2008) 0 7 mm partial PCL 8-11 mm isolated PCL 12 mm combined PCL injury *Pearl: posterior drawer test may underestimate PT Use of MRI to Diagnose PLC Injuries (LaPrade, 2000) Thin slice (2 mm) Entire fibular head / styloid Coronal obliques 1.5 or 3 tesla magnet Summary Understand complex anatomy Utilize clinical examination varus / PCL stress radiographs MRI to arrive at DX 7

9 2/22/2011 Steadman Philippon Research Institute Biomechanics Research Department THANK YOU 8

10 CURRENT CONCEPTS IN POSTEROLATERAL KNEE INJURY Rene J Abdalla, MD PhD Federal University of São Paulo, Brazil The postero-lateral compartment (PLC) structures are: lateral collateral ligament (LCL), popliteous muscle-tendon (PMT), the popliteofibular ligament (PFL) and the posterolateral capsule (PLC). The PLC restricts posterior tibial dislocation, provides the primary restrain to external tibial rotation at low knee flexion angles and also is the primary restrain to a knee varus movement, specially the LCL. Injury to the PLC can cause an important functional incapacity due to a knee varus instability associated to posterior and lateral knee rotation. PLC injuries can be classified according to their etiology: - Type 1: traumatic. The main mechanisms of injury are a direct blow to the antero-medial region of the tibia with the knee in near extension and the knee is forced into a hyperextension, external rotation and varus position. This injury can or cannot be associated to a cruciate ligament injury. A PLC isolated injury only occurs in 1.6% of the times. - Type 2: physiological instability. This can happen in people that have an excessive knee external rotation and have repetitive small traumas to the joint. In this case, a postero-lateral instability, without LCL or cruciate ligament injury, will occur. - Type 3: this is a combination of types 1 and 2. In this case, there is an isolated injury to the ACL or PCL in a patient with a prior excessive knee external rotation. The isolated cruciate ligament reconstruction will not correct the rotational instability. Diagnosis Injury to the PLC is often missed and under-diagnosed. Clinical diagnosis is given by the presence of a positive varus stress test, postero-lateral draw, positive dial test and the presence of the reverse pivot shift. Treatment Our group follows the subsequent guidelines of treatment: - All injuries associated to ACL or PCL injury should be treated surgically

11 - Isolated grades 1 or 2 PLC injuries: will depend on patient s symptoms - Isolated grade 3 PLC injuries: surgical treatment (described bellow). - Surgical technique Our group has established a new surgical technique for the PLC repair and is as follows: Autologous grafts are used for all reconstructions. The semi-tendinosus, the gracilis and the hemi-tendon of the biceps are used to replace the LCL, the popliteus tendon and the PFL. For the replacement of the popliteus tendon, a doubled semitendinous graft is used from anterior to posterior at the Gerdy tubercle towards a more proximal and lateral region of the tibial metaphysis. For this to be carried out correctly we use a PCL tibial guide that was devised by our group (Figure 1). Figure 1 PCL Tibial Guide The lateral collateral ligament is reproduced by a biceps hemi-tendon that is dissected from its insertion at the fibular head together with a section of the gracilis tendon. A tunnel is drilled in the head of the fibula at the LCL insertion site point and taking care to avoid the fibular nerve. The gracilis tendon is passed through this tunnel and one portion is joined to the biceps hemi-tendon to form the new LCL while the other portion is joined to the semi-tendinosous tendon to reproduce the popliteofibular ligament. Both groups are inserted at the lateral epicondyle at the anatomical position of the insertion site of the popliteous tendon and LCL (Figure 2).

12 Figure 2 Graft landmarks We have used this surgical technique since 1999 and, at the moment, have 18 patients with a 45-month follow-up. Of these, 10 also had an ACL injury and 8 had a PCL injury. At 3 years, the IKDC results showed that 13 subjects had a near-normal IKDC whereas 5 had abnormal results. Conclusion Although PLC injuries are becoming more frequent, diagnosis is still difficult and many times it is under-diagnosed. There are few high quality papers in the literature that can aid us in deciding the best treatment for our patients; in addition to this, many times our results are hard to evaluate because of the ACL and/or PCL simultaneous injury. There are many surgical techniques described but we still do not have the answer as to which is the best one. We believe that reconstruction should be anatomical, that patients should be followed so we can learn from our results and that more prospective studies should be performed.

13 REFERENCES 1. Abdalla RJ, Pacagnan AV, Loyola HA, Cohen M, Camanho GL, Forgas A. A proposal for a new tibial guide system for posterior cruciate ligament reconstruction. Arthroscopy Jul;23(7):793 e Baker CL Jr, Norwood LA, Hughston JC. Acute posterolateral rotatory instability of the knee. J Bone Joint Surg Am. 1983; 65: Clifford GR, Robin RL, Mark PC, Clifford Y, and Robert AA, Posterolateral Corner Reconstruction of the Knee, Evaluation of a Technique With Clinical Outcomes and Stress Radiography, AJSM PreView, published on May 5, 2010 as doi: / Cooper DE, Warren RF, Warner JP. The posterior cruciate ligament and posterolateral structures of the knee: anatomy, function, and patterns of injury. Instr Course Lect. 1991; 40: Covey D. Injuries to the posterolateral corner of the knee. J Bone Joint Surg Am. 2001; 83: DeLee JC, Riley MB, Rockwood CA Jr. Acute posterolateral rotator instability of the knee. Am J Sports Med. 1983; 11: Gollehon DL, Torzilli P, Warren RF. Th e role of the posterolateral and cruciate ligaments in the stability of the human knee: a biomechanical study. J Bone Joint Surg Am. 1987; 69: Hughston JC, Andrews JR, Cross MJ, Moschi A. Classification of knee ligament injuries: part II, the lateral compartment. J Bone Joint Surg Am. 1976; 58: LaPrade RF, Muench C, Wentorf F, Lewis JL. The effect of injury to the posterolateral structures of the knee on force in a posterior cruciate ligament graft: a biomechanical study. Am J Sports Med. 2002; 30: Latimer HA, Tibone JE, ElAttrache NS, McMahon PJ. Reconstruction of the lateral collateral ligament of the knee with patellar tendon allograft: report of a new technique in combined ligament injuries. Am J Sports Med. 1998; 26: Nielsen S, Helmig P. Posterior instability of the knee joint. Arch Orthop Trauma Surg. 1986; 105: Nielsen S, Helmig P. The static stabilizing function of the popliteal tendon in the knee: an experimental study. Arch Orthop TraumaSurg. 1986; 104: Nielsen S, Ovesen J, Rasmussen O. The posterior cruciate ligamentand rotatory knee instability: an experimental study. Arch Orthop Trauma Surg. 1985; 104: Noyes FR, Barber-Westin SD. Posterior cruciate ligament revision reconstruction: I, causes of surgical failure in 52 consecutive operations. Am J Sports Med. 2005;33: Veltri DM, Deng XH, Torzilli PA, Maynard MJ, Warren RF. The role of the popliteofibular ligament in stability of the human knee: a biomechanical study. Am J Sports Med. 1996; 24:19-27.

14 Varus Thrust and High Tibial Osteotomies to Treat Posterolateral Knee Injuries Markus P. ARNOLD, MD, PhD Senior Consultant, Knee Surgery Orthobiology & Cartilage Repair Dept. of Orthopaedic Surgery and Traumatology Kantonsspital Bruderholz CH-4101 Bruderholz, Switzerland Varus leg alignment itself is a normal variant of human anatomy regularly seen in active sportsmen. The biologic balance or joint homoeostasis may be guaranteed for decades, until one of the structures fails. In the varus aligned leg the forces are not ideally balanced: there is more tension stress and strain on the active and passive stabilizers on the lateral side than the structures are meant to sustain, and there is more axial pressure in the medial knee compartment. Clinical experience shows that a varus alignment itself may be no problem, but varus thrust may be the beginning of the end [3]. What is varus thrust? Varus thrust of the knee is a clinical observation of an abrupt, excessive varus moment of the knee, or in other words: a dynamic increase of a preexisting varus angle (Fig. 1). A thrust occurs due to the opening of the lateral tibio-femoral compartment upon initiation of load-bearing during normal gait [1]. Several anatomical structures stabilize the knee actively and passively against the varus thrust motion: the popliteal muscle-tendon, posterior joint capsule, iliotibial band and lateral collateral ligament (LCL). It has been suggested that these posterolateral structures of the knee act as a unit to balance a varus moment [2; 4]. The LCL is the most important passive stabilizer against a straight lateral thrust force. Insufficiency of this ligament will cause increased lateral compartment opening when external varus forces are applied.

15 It has been shown, that that even an intact lateral collateral ligament cannot prevent the development of a varus thrust [5] (Fig. 2). Changing the weight bearing line from 0% to 50% and from 50% to 100% varus increased the lateral joint opening significantly (Fig. 3). An isolated lateral or posterolateral ligamentous reconstruction would therefore have a hard time to survive the forces it had to face in the situation where a varus alignment has led to a varus thrust. A well-balanced valgus osteotomy with the goal to eliminate the dynamic phenomenon called varus thrust, mostly in order to reduce the tensile forces on the posterolateral active and passive stabilizers. Whether this mechanical leg correction should be performed before an eventual ligamentous reconstruction or as a combined procedure remains a topic for debate. [5] References: 1 Chang A, Hayes K, Dunlop D, et al. (2004) Thrust during ambulation and the progression of knee osteoarthritis. Arthritis Rheum, 50(12): Grood ES, Stowers SF, Noyes FR (1988) Limits of movement in the human knee. Effect of sectioning the posterior cruciate ligament and posterolateral structures. J Bone Joint Surg Am, 70(1): Noyes FR, Barber-Westin SD, Hewett TE (2000) High tibial osteotomy and ligament reconstruction for varus angulated anterior cruciate ligament-deficient knees. Am J Sports Med, 28(3): Noyes FR, Stowers SF, Grood ES, Cummings J, VanGinkel LA (1993) Posterior subluxations of the medial and lateral tibiofemoral compartments. An in vitro ligament sectioning study in cadaveric knees. Am J Sports Med, 21(3): van de Pol GJ, Arnold MP, Verdonschot N, van Kampen A (2009) Varus alignment leads to increased forces in the anterior cruciate ligament. Am J Sports Med, 37(3):

16 Figures: Fig. 1: a) b) Varus thrust explained: a discrete varus alignment a) is dynamically increased at the moment of varus thrust b). There is a lateral joint opening, the weight bearing line shifts to the medial side, the tension forces on the lateral active and passive stabilizers increases.

17 Fig. 2 Photograph of a leg in the compression machine. The ACL tensiometer and lateral extensiometer are mounted. The 100% varus weightbearing line (white line) passes through the medial edge of the tibial plateau. Fig 3: An example of a few loading cycles of an extended leg with the weightbearing line at the medial edge of the tibial plateau (100% varus), resulting in a visual thrusting pattern. The lateral joint opening curve is shown. The lateral joint opening occurred by axially loading an ACL intact knee, the test was started with a 25N preload and increased to 100N, 200N and 300N before returning to 25N

18 3/9/2011 Current Concepts of Posterolateral Knee Injury; Clinically Relevant Biomechanics Coen A. Wijdicks, Ph.D. Deputy Director Senior Staff Scientist Steadman Philippon Research Institute Biomechanics Research Department Purpose To measure the force in intact FCL, PLT, and PFL during in vitro loading. o Identify clinical relevance of these structures o Identify structures for anatomical surgical reconstruction in grade III posterolateral injuries LaPrade RF et al. AJSM 32, 2004 Purpose To measure lateral compartment opening secondary to applied varus stresses following posterolateral corner structure sectioning Ligamentous Structural Properties Measured the strength of the lateral collateral and popliteofibular ligaments To develop radiographic guidelines to quantify the amount of lateral compartment gapping seen with these injuries. LaPrade RF et al. JBJS 90, 2008 Sugita T and Amis AA. AJSM 29,

19 3/9/2011 Purpose To assist with the selection of reconstruction graft choices for anatomical posterolateral knee reconstruction techniques Rabbit Anatomy (JOR, 2003) Purpose Perform a detailed analysis of the anatomy of the posterolateral aspect of the rabbit knee, similar to previous studies of the human knee LaPrade RF et al. AJSM 33, 2005 Crum et al. JOR 21, 2003 RabbitSurgical Instability (JOR, 2004) Purpose Purpose was to develop an in vivo model for knee instability following a posterolateral corner injury. o Does the PLC heal? Rabbit Surgical Instability (AJSM, 2006) Purpose Determine the natural history of untreated posterolateral knee injuries at 6 months postoperatively o Long term outcome LaPrade et al. JOR 22, 2004 LaPrade et al. AJSM 34,

20 3/9/2011 Canine Anatomy and Biomechanics (JOR, 2007) Purpose To describe the anatomy and characterize the biomechanics of the posterolateral aspect of the canine knee. Canine Surgical Instability (AJSM, 2010) Purpose Evaluate articular cartilage cross sectional area and maximum thickness using 7.0 T magnetic resonance images. Compare to corresponding histologic sections. Griffith et al. J Orthop Res 25, 2007 Pepin et al. Am J Sports Med 37, 2010 Reconstruction Techniques Findings show that the popliteus muscletendonligament complex, fibular collateral ligament, and posterolateral capsular structures function as a unit. Operative reconstruction should address all of the posterolateral structures, since restoration of only a portion may result in residual instability. Purpose Restore varus and external rotary static stability to grade III PLC injured knees. Biomechanical testing o Intact (native) o Sectioned (injured) o reconstructed Pasque et al. J Bone Joint Surg Br 85, 2003 LaPrade et al. Am J Sports Med 32,

21 3/9/2011 Purpose Determine potential motion differences between anatomic knee reconstruction both with and without a PFL graft placed through a tibial tunnel. Biomechanical testing o Intact (native) o Sectioned (injured) o reconstructed Anatomic Reconstruction Technique 64 patients, 4.3 year follow up The posterolateral knee reconstruction technique significantly improved objective stability in patients. McCarthy et al. Am J Sports Med 33, 2010 LaPrade et al. J Bone Joint Surg Am 92, 2010 Summary Purpose To determine if untreated posterolateral knee injuries would result in measureable evidence of early onset arthritis on ultra high field MRI. FCL is primary restraint to varus. FCL and popliteus complex have complimentary or synergistic roles as stabilizers. Varus stress radiographs provide reliable measurements between clinicians. The posterolateral corner in the rabbit knee does not heal when injured. Even at 6 months. 7.0T MRI provides an alternative method to histology to evaluate early osteoarthritic changes. Operative reconstruction should address all of the posterolateral structures. Inclusion of the PFL through a tibial tunnel does not overconstrain the knee, and restored normal internal rotation. Griffith et al. ORS,

22 3/17/2011 Treatment of Acute Grade III Posterolateral Corner Injuries Posterolateral Knee Symposium ISAKOS 2011, Rio de Janeiro, Brazil Disclosures No potential conflicts of interest with the topic of this presentation. Andrew G. Geeslin, MD Indications Combined varus and posterolateral rotatory instability and/or a varus thrust gait Patient reported functional instability or pain Note: PE may be limited by pain in acute injuries Evaluation - Examination PE should include: Gait (if symptoms permit) Varus opening at 20 Posterolateral drawer Dial at 30 & 90 Reverse pivot shift Evaluation: Imaging Clinically Relevant Anatomy FCL Popliteus tendon PFL Lateral Capsule Biceps Femoris Iliotibial Band LaPrade et al., AJSM

23 3/17/2011 PLC Injury Assessment Stepwise search for injuries to structures with attachments to: 1. Fibula 2. Femur 3. Tibia 4. Lateral Meniscus PLC Injury: Approach & Neurolysis Geeslin and LaPrade., TKS 2011 LaPrade et al., AJSM 2003 PLC Assessment: Fibular Head PLC Assessment: Lateral Femur Structures attached to fibular head: Biceps femoris tendon FCL PFL Perform ITB splitting incision to visualize: FCL PLT PLC Assessment: Tibia, Lateral Meniscus Mid-Third Lateral Capsular Ligament Meniscotibial Meniscofemoral Arthroscopic Assessment Performed after open PLC dissection Reconstruct ACL and PCL as indicated Only secure femoral grafts at this time Treat meniscus, debride cartilage as indicated 2

24 3/17/2011 Technique: Repair vs. Reconstruction Technique: Popliteus Recess Procedure Repairable: Avulsion off bone Non-repairable: Midsubstance tear, stretch injury Order of treatment: 1. Femur 2. Lateral Meniscus 3. Tibia 4. Fibular head/styloid Performed when popliteus tendon is avulsed from its femoral attachment without intrasubstance stretch, musculotendinous avulsion Technique: Popliteus Recess Procedure Vertical incision through capsular ligament to identify the PLT anatomic attachment Dissect under VMO; use aiming guide, eyelet pin Ream 5 mm tunnel, 1 cm deep Advance tendon, tie sutures over medial button Technique: FCL Reconstruction Performed when PLT does not require reconstruction and PFL is intact Semitendinosus autograft Biomechanically Validated (Coobs et al., AJSM 2007) Clinically Validated (LaPrade et al. AJSM 2010) Coobs et al., AJSM 2007 Technique: PLC Reconstruction Technique: Repairs Anatomic PLCR performed when FCL and PLT are torn and non-repairable Biomechanically validated (LaPrade et al., AJSM 2004) Clinically validated (LaPrade et al., JBJS 2010) Lateral capsule suture anchors Popliteomeniscal fascicles mattress sutures Coronary ligament mattress sutures LaPrade et al., AJSM

25 3/17/2011 Technique: Biceps Femoris Tendon Avulsion May require proximal release due to retraction Repaired with suture anchors with the knee in full extension Technique: PFL Repair or Reconstruction PFL suture anchor repair if FCL or PLT intact FCL/PFL Reconstruction when PFL non-repairable and FCL tear Outcomes: Acute Grade III PLC Injury Outcomes: Subjective Demographics 29 Patients, 30 Knees Average age 27 (16-63) Mechanism of Injury 7 high, 23 low velocity 19 due to sporting activities Associated Injuries 8 isolated, 10 w/acl, 4 w/pcl, 8 w/acl + PCL Final study group 25 pts (26 knees) with 2 yrs (avg 2.4) follow-up Subjective Eval Cincinnati Symptoms, Fn IKDC Subjective Objective Eval IKDC Varus Stress Comparison of average subscores at final follow-up Outcomes: IKDC Objective Stability Conclusions FCL, popliteus tendon, PFL Anatomic repair of avulsions, reconstruction of midsubstance tears and intra-substance stretch injuries Anatomic repair of other posterolateral structures with knee in full extension Posterolateral stability and single-leg-hop scores (A=normal, B=nearly normal, C=abnormal, D=severely abnormal) Single stage cruciate ligament reconstruction recommended 4