Technical Note
Medial Patellofemoral Ligament Reconstruction: A New Technique for Graft Fixation at the Patella Without Implants Sven Shafizadeh, M.D., and Maurice Balke, M.D.
Abstract: Patellofemoral instability is a complex disorder that is often accompanied by insufficiency or tearing of the medial patellofemoral ligament. Over the past few years, several techniques using free tendon grafts for medial patellofemoral ligament reconstruction have become popular because of their reproducible effect and good outcome. Whereas most surgeons prefer femoral fixation of the graft using an interference screw, the possibilities of patellar fixation are numerous. All of the different techniques have their own advantages and pitfalls. We describe a technique in which we drill 2 blind-ending tunnels (1 cm) at the medial aspect of the patella, where the doubled graft (not the free ends) is pulled in and fixed. By using a special technique for shuttling the sutures, there is no need for an additional skin incision and no need for implants, allowing very secure graft fixation without a relevant risk of fracture.
P
atellofemoral instability is a complex disorder. Among various predispositions such as genu valgum, dysplasia of the femoral trochlea, patella alta, coxa antetorta, and increased distance of the tibial tuberosityetrochlear groove, patellofemoral instability is often accompanied by insufficiency or tearing of the medial patellofemoral ligament (MPFL). The MPFL has been described as the most important passive stabilizer on the medial aspect of the patella, especially from 0 to 45 of knee flexion.1-4 In most cases the first dislocation of the patella causes an elongation or traumatic tearing of the MPFL, leading to patella maltracking and insufficiency of the medial stabilizers of the patellofemoral joint. This can cause chronic symptomatic instability of the patella. Over the past few years, several techniques to reconstruct the medial stabilizers of the patella have been described. In particular, surgical techniques using free tendon grafts for MPFL reconstruction have become
From the Department of Trauma, Orthopaedic Surgery, and Athletic Injuries, Cologne Merheim Medical Center, University of Witten/Herdecke, Cologne, Germany. The authors report that they have no conflicts of interest in the authorship and publication of this article. Received June 7, 2013; accepted September 6, 2013. Address correspondence to Sven Shafizadeh, M.D., Department of Trauma, Orthopaedic Surgery, and Athletic Injuries, Cologne Merheim Medical Center, University of Witten/Herdecke, Ostmerheimer Strasse 200, 51109 Cologne, Germany. E-mail: Shafi[email protected] Ó 2014 by the Arthroscopy Association of North America 2212-6287/13379/$36.00 http://dx.doi.org/10.1016/j.eats.2013.09.005
Arthroscopy Techniques, Vol
-,
popular because of their reproducible effect and good outcome.5-8 Therefore different grafts, as well as a plethora of techniques for fixation of the graft on the medial aspect of the patella, are available.9-15 Commonly used are the tendons of the gracilis or semitendinosus muscle. Whereas most surgeons prefer femoral fixation of the graft using an interference screw, the possibilities of patellar fixation are numerous. All of the different techniques have their own advantages and pitfalls.8,16 The use of interference screws with a smaller diameter also for patellar graft fixation enables one to securely attach the graft to the patella.12 Because 2 screws are necessary, costs are relatively high. This also accounts for the use of 2 suture anchors.13 Drilling through the patella, pulling through of the graft, and fixing it by tying the attached sutures at the lateral aspect of the patella would be more cost-effective but is also accompanied by an increased risk of patellar fracture.1,2 Petersen and Zantop17 have published a technique in which they only drilled 2 holes at the medial aspect of the patella in the size of the graft. Then, only a wire is used to drill through the rest of the patella and the lateral cortex. Both free ends of the graft, armed with sutures, are pulled into the tunnels, and the sutures are pulled through the bone and tied over the lateral patella after establishment of an additional skin incision. This technique is also cost-effective with only a very low risk of fracture of the patella. The drawback is the necessity for an additional skin incision on the lateral side. Similarly, we drill 2 blind-ending tunnels (1 cm) at the medial aspect of the patella, where the doubled graft (not the free ends) is pulled in and fixed. By
No
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(Month), 2014: pp e1-e3
e1
e2
S. SHAFIZADEH AND M. BALKE Fig 1. Drawing of implant-free graft fixation using special shuttling technique. Two 4.5-mm holes with a depth of 1 cm are drilled at the lateral aspect of the patella. A 2.4-mm wire with a small eyelet at the end is drilled through the lateral cortex (A), and 1 suture per hole is shuttled through the patella and retrieved through the anterolateral arthroscopy portal on the lateral side (B). By use of our shuttling technique, 2 sutures are passed through the patella and around the lateral cortex (B-D). The middle part of the graft is inserted into the loops (E) and pulled press-fit into the bone tunnels (F). Tying the knots allows very secure graft fixation.
using a special technique for shuttling the sutures, there is no need for an additional skin incision, allowing very secure graft fixation without a relevant risk of fracture.
Surgical Technique We routinely use the ipsilateral gracilis tendon as a free tendon graft. Graft harvesting is performed as described for anterior cruciate ligament reconstruction. Both free ends of the tendon are armed by use of a web-stitch technique using No. 2 Vicryl sutures (Ethicon, Somerville, NJ). For exposure of the medial aspect of the patella, we prefer a 2-cm transversal incision along the proximal third of the patella. All soft tissue is carefully removed from the bone, and a small groove is prepared at the medial patella, similar to that used for suture anchor fixation. Approximately 5 mm distal to the attachment of the medial vastus muscle, a 2.4-mm wire with a small eyelet at the end is drilled through the patella from medial to lateral. By use of a cannulated 4.5-mm drill, a tunnel with a depth of 1 cm is drilled over the wire (Fig 1A). A No. 2 Ethibond suture (Ethicon) is inserted through the eyelet of the wire in a loop configuration. By moving the mobile skin at the lateral side, the wire is then passed through the skin incision of the previously used anterolateral arthroscopy portal or simply pierced through the skin. By pulling the wire through the patella, the loop is passed from medial to lateral. A second similar drill hole is made more distally, and a second Ethibond suture is passed through it using the same technique (Fig 1B). The length of the bone bridge between both 2.4-mm drill holes on the lateral aspect of the patella should be around 15 mm. Next, 1 suture is passed through the loop of the other suture, which is then pulled medially. One U-shaped suture should then run through both drill holes over the bone bridge at the lateral aspect of the patella (Fig 1C). Two opposed doubled FiberWire
sutures (Arthrex, Naples, FL) (the loop of 1 suture and both free ends of the other suture) are passed through the loop of the U-shaped Ethibond suture, which is pulled around the lateral bone bridge medially through the drill holes (Fig 1D). The 2 free ends of 1 FiberWire suture and the loop of the other suture should be at the proximal and medial drill holes. The graft is passed through both loops; the middle part of the graft should be centrally arranged (Fig 1E). By pulling on the free ends of both sutures (proximal and distal), the graft is pulled press-fit into the 1-cm bone tunnels (Fig 1F). Fixation of the graft is achieved by tying the free ends over the graft at the proximal and distal bone tunnels. Video 1 presents an overview of the entire procedure. Important pearls are summarized in Table 1. The femoral bone tunnel is then established under radiographic control with a C-arm. A 2-cm skin incision is made over the tubercle, and a 2.4-mm wire is drilled under radiographic control, slightly ascending through the lateral cortex of the femur. By use of a 6-mm cannulated drill, a bone tunnel is made at the medial tubercle. Another suture is passed through the eyelet at the end of the wire and pulled through the bone. Both free ends of the graft, already armed with sutures, are passed between the second and third capsular layer and through the femoral shuttling suture. Both ends of the graft are pulled into the bone and fixed with a 6-mm interference screw at 15 of knee flexion. Attention is paid not to over-tighten the graft. Table 1. Important Pearls for Implant-Free MPFL Graft Fixation at Patella The subcutaneous tissue should be mobilized over the anterolateral arthroscopy portal to avoid soft-tissue entrapment. With the use of an acromionizer, a small groove at the medial aspect of the patella is easily prepared. A “plop” will be felt when the graft is pulled press-fit into the bone. The surgeon should ensure that the graft is centrally arranged within the loops.
MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION
After surgery, we recommend partial weight bearing with 20 kg and non-restricted mobilization of the knee joint. A special orthosis is not necessary.
8.
Discussion Since 2011, 48 patients (34 female and 14 male patients) with patellofemoral instability have been treated at our institution using the described technique. We have not observed any complications thus far. In 1 case this technique was used as a salvage procedure after failed fixation with interference screws. After a minimum follow-up period of 6 months, all patients had free range of motion, no pain, and no recurrent instability. The possible risks of our procedure are fracture of the patella, entrapment of subcutaneous tissue at the lateral aspect of the patella, and loosening of the sutures.
References 1. Amis AA. Current concepts on anatomy and biomechanics of patellar stability. Sports Med Arthrosc 2007;15:48-56. 2. Bicos J, Fulkerson JP, Amis A. Current concepts review: The medial patellofemoral ligament. Am J Sports Med 2007;35:484-492. 3. Feller JA, Amis AA, Andrish JT, Arendt EA, Erasmus PJ, Powers CM. Surgical biomechanics of the patellofemoral joint. Arthroscopy 2007;23:542-553. 4. Mountney J, Senavongse W, Amis AA, Thomas NP. Tensile strength of the medial patellofemoral ligament before and after repair or reconstruction. J Bone Joint Surg Br 2005;87:36-40. 5. Schepsis AA, Rogers AJ. Medial patellofemoral ligament reconstruction: Indications and technique. Sports Med Arthrosc 2012;20:162-170. 6. Buckens CF, Saris DB. Reconstruction of the medial patellofemoral ligament for treatment of patellofemoral instability: A systematic review. Am J Sports Med 2010;38: 181-188. 7. Fisher B, Nyland J, Brand E, Curtin B. Medial patellofemoral ligament reconstruction for recurrent patellar dislocation: A systematic review including rehabilitation
9.
10.
11.
12.
13.
14.
15.
16.
17.
e3
and return-to-sports efficacy. Arthroscopy 2010;26: 1384-1394. Shah JN, Howard JS, Flanigan DC, Brophy RH, Carey JL, Lattermann C. A systematic review of complications and failures associated with medial patellofemoral ligament reconstruction for recurrent patellar dislocation. Am J Sports Med 2012;40:1916-1923. Carmont MR, Carey-Smith R, Saithna A, Dhillon M, Thompson P, Spalding T. Delayed incorporation of a TruFit plug: Perseverance is recommended. Arthroscopy 2009;25:810-814. Christiansen SE, Jacobsen BW, Lund B, Lind M. Reconstruction of the medial patellofemoral ligament with gracilis tendon autograft in transverse patellar drill holes. Arthroscopy 2008;24:82-87. Mikashima Y, Kimura M, Kobayashi Y, Miyawaki M, Tomatsu T. Clinical results of isolated reconstruction of the medial patellofemoral ligament for recurrent dislocation and subluxation of the patella. Acta Orthop Belg 2006;72:65-71. Schöttle P, Beitzel K, Imhoff A. The child’s patellar dislocation. Anatomy, pathological anatomy and treatment strategies. Arthroskopie 2009;22:51-59 [in German]. Schottle P, Schmeling A, Romero J, Weiler A. Anatomical reconstruction of the medial patellofemoral ligament using a free gracilis autograft. Arch Orthop Trauma Surg 2009;129:305-309. Schottle PB, Fucentese SF, Romero J. Clinical and radiological outcome of medial patellofemoral ligament reconstruction with a semitendinosus autograft for patella instability. Knee Surg Sports Traumatol Arthrosc 2005;13: 516-521. Steensen RN, Dopirak RM, Maurus PB. A simple technique for reconstruction of the medial patellofemoral ligament using a quadriceps tendon graft. Arthroscopy 2005;21:365-370. Tanaka MJ, Bollier MJ, Andrish JT, Fulkerson JP, Cosgarea AJ. Complications of medial patellofemoral ligament reconstruction: Common technical errors and factors for success: AAOS exhibit selection. J Bone Joint Surg Am 2012;94:e871-e878. Petersen W, Zantop T. A new method for fixation of patellar MPFL - transplants. Arthroskopie 2009;22:237-240 [in German].
Medial Patellofemoral Ligament Reconstruction: A New Technique for Graft Fixation at the Patella Without Implants Sven Shafizadeh, M.D., and Maurice Balke, M.D.
Abstract: Patellofemoral instability is a complex disorder that is often accompanied by insufficiency or tearing of the medial patellofemoral ligament. Over the past few years, several techniques using free tendon grafts for medial patellofemoral ligament reconstruction have become popular because of their reproducible effect and good outcome. Whereas most surgeons prefer femoral fixation of the graft using an interference screw, the possibilities of patellar fixation are numerous. All of the different techniques have their own advantages and pitfalls. We describe a technique in which we drill 2 blind-ending tunnels (1 cm) at the medial aspect of the patella, where the doubled graft (not the free ends) is pulled in and fixed. By using a special technique for shuttling the sutures, there is no need for an additional skin incision and no need for implants, allowing very secure graft fixation without a relevant risk of fracture.
P
atellofemoral instability is a complex disorder. Among various predispositions such as genu valgum, dysplasia of the femoral trochlea, patella alta, coxa antetorta, and increased distance of the tibial tuberosityetrochlear groove, patellofemoral instability is often accompanied by insufficiency or tearing of the medial patellofemoral ligament (MPFL). The MPFL has been described as the most important passive stabilizer on the medial aspect of the patella, especially from 0 to 45 of knee flexion.1-4 In most cases the first dislocation of the patella causes an elongation or traumatic tearing of the MPFL, leading to patella maltracking and insufficiency of the medial stabilizers of the patellofemoral joint. This can cause chronic symptomatic instability of the patella. Over the past few years, several techniques to reconstruct the medial stabilizers of the patella have been described. In particular, surgical techniques using free tendon grafts for MPFL reconstruction have become
From the Department of Trauma, Orthopaedic Surgery, and Athletic Injuries, Cologne Merheim Medical Center, University of Witten/Herdecke, Cologne, Germany. The authors report that they have no conflicts of interest in the authorship and publication of this article. Received June 7, 2013; accepted September 6, 2013. Address correspondence to Sven Shafizadeh, M.D., Department of Trauma, Orthopaedic Surgery, and Athletic Injuries, Cologne Merheim Medical Center, University of Witten/Herdecke, Ostmerheimer Strasse 200, 51109 Cologne, Germany. E-mail: Shafi[email protected] Ó 2014 by the Arthroscopy Association of North America 2212-6287/13379/$36.00 http://dx.doi.org/10.1016/j.eats.2013.09.005
Arthroscopy Techniques, Vol
-,
popular because of their reproducible effect and good outcome.5-8 Therefore different grafts, as well as a plethora of techniques for fixation of the graft on the medial aspect of the patella, are available.9-15 Commonly used are the tendons of the gracilis or semitendinosus muscle. Whereas most surgeons prefer femoral fixation of the graft using an interference screw, the possibilities of patellar fixation are numerous. All of the different techniques have their own advantages and pitfalls.8,16 The use of interference screws with a smaller diameter also for patellar graft fixation enables one to securely attach the graft to the patella.12 Because 2 screws are necessary, costs are relatively high. This also accounts for the use of 2 suture anchors.13 Drilling through the patella, pulling through of the graft, and fixing it by tying the attached sutures at the lateral aspect of the patella would be more cost-effective but is also accompanied by an increased risk of patellar fracture.1,2 Petersen and Zantop17 have published a technique in which they only drilled 2 holes at the medial aspect of the patella in the size of the graft. Then, only a wire is used to drill through the rest of the patella and the lateral cortex. Both free ends of the graft, armed with sutures, are pulled into the tunnels, and the sutures are pulled through the bone and tied over the lateral patella after establishment of an additional skin incision. This technique is also cost-effective with only a very low risk of fracture of the patella. The drawback is the necessity for an additional skin incision on the lateral side. Similarly, we drill 2 blind-ending tunnels (1 cm) at the medial aspect of the patella, where the doubled graft (not the free ends) is pulled in and fixed. By
No
-
(Month), 2014: pp e1-e3
e1
e2
S. SHAFIZADEH AND M. BALKE Fig 1. Drawing of implant-free graft fixation using special shuttling technique. Two 4.5-mm holes with a depth of 1 cm are drilled at the lateral aspect of the patella. A 2.4-mm wire with a small eyelet at the end is drilled through the lateral cortex (A), and 1 suture per hole is shuttled through the patella and retrieved through the anterolateral arthroscopy portal on the lateral side (B). By use of our shuttling technique, 2 sutures are passed through the patella and around the lateral cortex (B-D). The middle part of the graft is inserted into the loops (E) and pulled press-fit into the bone tunnels (F). Tying the knots allows very secure graft fixation.
using a special technique for shuttling the sutures, there is no need for an additional skin incision, allowing very secure graft fixation without a relevant risk of fracture.
Surgical Technique We routinely use the ipsilateral gracilis tendon as a free tendon graft. Graft harvesting is performed as described for anterior cruciate ligament reconstruction. Both free ends of the tendon are armed by use of a web-stitch technique using No. 2 Vicryl sutures (Ethicon, Somerville, NJ). For exposure of the medial aspect of the patella, we prefer a 2-cm transversal incision along the proximal third of the patella. All soft tissue is carefully removed from the bone, and a small groove is prepared at the medial patella, similar to that used for suture anchor fixation. Approximately 5 mm distal to the attachment of the medial vastus muscle, a 2.4-mm wire with a small eyelet at the end is drilled through the patella from medial to lateral. By use of a cannulated 4.5-mm drill, a tunnel with a depth of 1 cm is drilled over the wire (Fig 1A). A No. 2 Ethibond suture (Ethicon) is inserted through the eyelet of the wire in a loop configuration. By moving the mobile skin at the lateral side, the wire is then passed through the skin incision of the previously used anterolateral arthroscopy portal or simply pierced through the skin. By pulling the wire through the patella, the loop is passed from medial to lateral. A second similar drill hole is made more distally, and a second Ethibond suture is passed through it using the same technique (Fig 1B). The length of the bone bridge between both 2.4-mm drill holes on the lateral aspect of the patella should be around 15 mm. Next, 1 suture is passed through the loop of the other suture, which is then pulled medially. One U-shaped suture should then run through both drill holes over the bone bridge at the lateral aspect of the patella (Fig 1C). Two opposed doubled FiberWire
sutures (Arthrex, Naples, FL) (the loop of 1 suture and both free ends of the other suture) are passed through the loop of the U-shaped Ethibond suture, which is pulled around the lateral bone bridge medially through the drill holes (Fig 1D). The 2 free ends of 1 FiberWire suture and the loop of the other suture should be at the proximal and medial drill holes. The graft is passed through both loops; the middle part of the graft should be centrally arranged (Fig 1E). By pulling on the free ends of both sutures (proximal and distal), the graft is pulled press-fit into the 1-cm bone tunnels (Fig 1F). Fixation of the graft is achieved by tying the free ends over the graft at the proximal and distal bone tunnels. Video 1 presents an overview of the entire procedure. Important pearls are summarized in Table 1. The femoral bone tunnel is then established under radiographic control with a C-arm. A 2-cm skin incision is made over the tubercle, and a 2.4-mm wire is drilled under radiographic control, slightly ascending through the lateral cortex of the femur. By use of a 6-mm cannulated drill, a bone tunnel is made at the medial tubercle. Another suture is passed through the eyelet at the end of the wire and pulled through the bone. Both free ends of the graft, already armed with sutures, are passed between the second and third capsular layer and through the femoral shuttling suture. Both ends of the graft are pulled into the bone and fixed with a 6-mm interference screw at 15 of knee flexion. Attention is paid not to over-tighten the graft. Table 1. Important Pearls for Implant-Free MPFL Graft Fixation at Patella The subcutaneous tissue should be mobilized over the anterolateral arthroscopy portal to avoid soft-tissue entrapment. With the use of an acromionizer, a small groove at the medial aspect of the patella is easily prepared. A “plop” will be felt when the graft is pulled press-fit into the bone. The surgeon should ensure that the graft is centrally arranged within the loops.
MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION
After surgery, we recommend partial weight bearing with 20 kg and non-restricted mobilization of the knee joint. A special orthosis is not necessary.
8.
Discussion Since 2011, 48 patients (34 female and 14 male patients) with patellofemoral instability have been treated at our institution using the described technique. We have not observed any complications thus far. In 1 case this technique was used as a salvage procedure after failed fixation with interference screws. After a minimum follow-up period of 6 months, all patients had free range of motion, no pain, and no recurrent instability. The possible risks of our procedure are fracture of the patella, entrapment of subcutaneous tissue at the lateral aspect of the patella, and loosening of the sutures.
References 1. Amis AA. Current concepts on anatomy and biomechanics of patellar stability. Sports Med Arthrosc 2007;15:48-56. 2. Bicos J, Fulkerson JP, Amis A. Current concepts review: The medial patellofemoral ligament. Am J Sports Med 2007;35:484-492. 3. Feller JA, Amis AA, Andrish JT, Arendt EA, Erasmus PJ, Powers CM. Surgical biomechanics of the patellofemoral joint. Arthroscopy 2007;23:542-553. 4. Mountney J, Senavongse W, Amis AA, Thomas NP. Tensile strength of the medial patellofemoral ligament before and after repair or reconstruction. J Bone Joint Surg Br 2005;87:36-40. 5. Schepsis AA, Rogers AJ. Medial patellofemoral ligament reconstruction: Indications and technique. Sports Med Arthrosc 2012;20:162-170. 6. Buckens CF, Saris DB. Reconstruction of the medial patellofemoral ligament for treatment of patellofemoral instability: A systematic review. Am J Sports Med 2010;38: 181-188. 7. Fisher B, Nyland J, Brand E, Curtin B. Medial patellofemoral ligament reconstruction for recurrent patellar dislocation: A systematic review including rehabilitation
9.
10.
11.
12.
13.
14.
15.
16.
17.
e3
and return-to-sports efficacy. Arthroscopy 2010;26: 1384-1394. Shah JN, Howard JS, Flanigan DC, Brophy RH, Carey JL, Lattermann C. A systematic review of complications and failures associated with medial patellofemoral ligament reconstruction for recurrent patellar dislocation. Am J Sports Med 2012;40:1916-1923. Carmont MR, Carey-Smith R, Saithna A, Dhillon M, Thompson P, Spalding T. Delayed incorporation of a TruFit plug: Perseverance is recommended. Arthroscopy 2009;25:810-814. Christiansen SE, Jacobsen BW, Lund B, Lind M. Reconstruction of the medial patellofemoral ligament with gracilis tendon autograft in transverse patellar drill holes. Arthroscopy 2008;24:82-87. Mikashima Y, Kimura M, Kobayashi Y, Miyawaki M, Tomatsu T. Clinical results of isolated reconstruction of the medial patellofemoral ligament for recurrent dislocation and subluxation of the patella. Acta Orthop Belg 2006;72:65-71. Schöttle P, Beitzel K, Imhoff A. The child’s patellar dislocation. Anatomy, pathological anatomy and treatment strategies. Arthroskopie 2009;22:51-59 [in German]. Schottle P, Schmeling A, Romero J, Weiler A. Anatomical reconstruction of the medial patellofemoral ligament using a free gracilis autograft. Arch Orthop Trauma Surg 2009;129:305-309. Schottle PB, Fucentese SF, Romero J. Clinical and radiological outcome of medial patellofemoral ligament reconstruction with a semitendinosus autograft for patella instability. Knee Surg Sports Traumatol Arthrosc 2005;13: 516-521. Steensen RN, Dopirak RM, Maurus PB. A simple technique for reconstruction of the medial patellofemoral ligament using a quadriceps tendon graft. Arthroscopy 2005;21:365-370. Tanaka MJ, Bollier MJ, Andrish JT, Fulkerson JP, Cosgarea AJ. Complications of medial patellofemoral ligament reconstruction: Common technical errors and factors for success: AAOS exhibit selection. J Bone Joint Surg Am 2012;94:e871-e878. Petersen W, Zantop T. A new method for fixation of patellar MPFL - transplants. Arthroskopie 2009;22:237-240 [in German].
