Orthopedics

Case Reports 

Transverse Femoral Implant Prominence: Four Cases Demonstrating a Preventable Complication for ACL Reconstruction

Evan Argintar, MD; Benjamin Scherer, BS; Tom Jordan, MD; John Klimkiewicz, MD

  • Orthopedics. 2010;33(12)
  • Posted December 1, 2010

Abstract

Anterior cruciate ligament (ACL) tear is a commonly occurring injury that often demands surgical reconstruction. Although the utility of this operation is widely accepted, many specific components, including graft fixation technique, remain controversial. Many clinicians favor transverse femoral implant fixation for soft tissue ACL grafts. This technique can be accomplished successfully; however, in a minority of the cases, the femoral implant can be excessively prominent, leading to iatrogenic postoperative iliotibial band syndrome.

This article presents 4 patients that developed postoperative iliotibial band syndrome resulting from transverse femoral implant prominence. Despite achievement of knee ligamentous stability, implant prominence compromised final clinical results following ACL reconstruction. Through change in Lysholm value, we reviewed the clinical outcomes of these patients following femoral implant hardware removal for treatment of iliotibial band syndrome. On hardware removal, all patients demonstrated complete symptomatic improvement, mirroring an average Lysholm value increase of 38. We believe transverse femoral implant prominence is avoidable, and subsequent iliotibial band syndrome is a preventable postoperative complication.

Anterior cruciate ligament (ACL) tear is a commonly occurring injury that often demands surgical reconstruction. Although the utility of this operation is widely accepted, many specific components of ACL reconstruction remain controversial. Graft fixation method is one such example, with options including interference screws, staples, EndoButtons (Smith & Nephew Endoscopy, Andover, Massachusetts), and transverse femoral implant fixation. Each of these options carries device-specific complications that must be avoided to obtain satisfactory results following ACL reconstruction.

Many clinicians favor transverse femoral implant fixation for soft tissue ACL grafts. This technique can be accomplished successfully; however, in a minority of cases, the femoral implant can be left or become excessively prominent. The iatrogenic postoperative iliotibial band syndrome may develop, leading to activity-restricting pain (Figure). Despite the achievement of knee ligamentous stability, the subsequent iliotibial band irritation can compromise final clinical outcomes.

This article presents 4 athletic patients between the ages of 28 and 44 years who presented with debilitating iatrogenic iliotibial band syndrome as a result of prominent lateral femoral fixation following ACL reconstruction that had complete symptomatic resolution following hardware removal.

Patient 1

A 29-year-old woman sustained an ACL tear while playing flag football and underwent ACL reconstruction with a soft tissue allograft. At 2 years postoperatively, the patient reported no knee instability; however, she also reported continued lateral knee pain that developed with activities. She was unable to participate in organized group athletics. This limitation was progressive in nature, beginning several months after the patient returned to unrestricted athletic involvement. The pain was described as severe and without radiation.

On physical examination, the knee was well aligned, and pain was exacerbated with direct palpation to the distal lateral femur. This focal tenderness was maximal at the lateral implant prominence, which tented the lateral knee skin with knee flexion. Otherwise, the knee was found to be stable, with negative Lachman and pivot-shift maneuvers. Femoral pin removal was completed with complete resolution of symptoms.

Patient 2

A 33-year-old woman sustained an ACL tear after a fall while at work as a secretary and underwent ACL reconstruction. At 2 years postoperatively, the patient reported a stable knee that had a sharp lateral pain associated with climbing stairs and squatting positions. The patient was unable to play recreational sports. This pain was progressive in nature, increasing in magnitude as the patient began resuming athletic involvement.

Physical examination demonstrated a normally aligned knee with lateral tenderness along the distal femur. Motion was nearly symmetric to the contralateral side, and Lachman and pivot-shift maneuvers were negative. Femoral pin removal was completed, with complete resolution of symptoms.

Patient 3

A 44-year-old woman sustained an…

Abstract

Anterior cruciate ligament (ACL) tear is a commonly occurring injury that often demands surgical reconstruction. Although the utility of this operation is widely accepted, many specific components, including graft fixation technique, remain controversial. Many clinicians favor transverse femoral implant fixation for soft tissue ACL grafts. This technique can be accomplished successfully; however, in a minority of the cases, the femoral implant can be excessively prominent, leading to iatrogenic postoperative iliotibial band syndrome.

This article presents 4 patients that developed postoperative iliotibial band syndrome resulting from transverse femoral implant prominence. Despite achievement of knee ligamentous stability, implant prominence compromised final clinical results following ACL reconstruction. Through change in Lysholm value, we reviewed the clinical outcomes of these patients following femoral implant hardware removal for treatment of iliotibial band syndrome. On hardware removal, all patients demonstrated complete symptomatic improvement, mirroring an average Lysholm value increase of 38. We believe transverse femoral implant prominence is avoidable, and subsequent iliotibial band syndrome is a preventable postoperative complication.

Anterior cruciate ligament (ACL) tear is a commonly occurring injury that often demands surgical reconstruction. Although the utility of this operation is widely accepted, many specific components of ACL reconstruction remain controversial. Graft fixation method is one such example, with options including interference screws, staples, EndoButtons (Smith & Nephew Endoscopy, Andover, Massachusetts), and transverse femoral implant fixation. Each of these options carries device-specific complications that must be avoided to obtain satisfactory results following ACL reconstruction.

Many clinicians favor transverse femoral implant fixation for soft tissue ACL grafts. This technique can be accomplished successfully; however, in a minority of cases, the femoral implant can be left or become excessively prominent. The iatrogenic postoperative iliotibial band syndrome may develop, leading to activity-restricting pain (Figure). Despite the achievement of knee ligamentous stability, the subsequent iliotibial band irritation can compromise final clinical outcomes.

Figure: lateral femoral implant prominence
Figure: T2-weighted coronal MRI demonstrating lateral femoral implant prominence with surrounding soft tissue edema.

This article presents 4 athletic patients between the ages of 28 and 44 years who presented with debilitating iatrogenic iliotibial band syndrome as a result of prominent lateral femoral fixation following ACL reconstruction that had complete symptomatic resolution following hardware removal.

Case Reports

Patient 1

A 29-year-old woman sustained an ACL tear while playing flag football and underwent ACL reconstruction with a soft tissue allograft. At 2 years postoperatively, the patient reported no knee instability; however, she also reported continued lateral knee pain that developed with activities. She was unable to participate in organized group athletics. This limitation was progressive in nature, beginning several months after the patient returned to unrestricted athletic involvement. The pain was described as severe and without radiation.

On physical examination, the knee was well aligned, and pain was exacerbated with direct palpation to the distal lateral femur. This focal tenderness was maximal at the lateral implant prominence, which tented the lateral knee skin with knee flexion. Otherwise, the knee was found to be stable, with negative Lachman and pivot-shift maneuvers. Femoral pin removal was completed with complete resolution of symptoms.

Patient 2

A 33-year-old woman sustained an ACL tear after a fall while at work as a secretary and underwent ACL reconstruction. At 2 years postoperatively, the patient reported a stable knee that had a sharp lateral pain associated with climbing stairs and squatting positions. The patient was unable to play recreational sports. This pain was progressive in nature, increasing in magnitude as the patient began resuming athletic involvement.

Physical examination demonstrated a normally aligned knee with lateral tenderness along the distal femur. Motion was nearly symmetric to the contralateral side, and Lachman and pivot-shift maneuvers were negative. Femoral pin removal was completed, with complete resolution of symptoms.

Patient 3

A 44-year-old woman sustained an ACL injury after a fall and underwent ACL reconstruction. At 1.5 years postoperatively, the patient reported continued sharp lateral knee pain without radiation that was worse with applied pressure. Pain was exacerbated with hiking and walking long distances. The pain was worse with extension, and the patient was unable to play tennis or other competitive team sports.

On physical examination, the knee was well aligned, with focal tenderness over the laterally prominent implant on the distal femur. Motion was limited at extremes, with a flexion contracture of 10° and flexion to 90°. The knee was stable, with negative Lachman and pivot-shift maneuvers. At 1.5 years after index ACL reconstruction, the femoral implant was surgically removed, with complete resolution of symptoms.

Patient 4

A 28-year-old man sustained an ACL injury during a skiing accident and underwent ACL reconstruction. At 2 years postoperatively, the patient reported a stable knee with persistent progressively increasing lateral knee pain. The patient reported implant prominence that became progressively sensitive with hard touch. Running, kneeling, yoga, and touching the implant were painful, and the patient was unable to participate in these activities.

On physical examination, the knee was well aligned, with focal tenderness laterally along the distal femur centered on the prominent femoral implant. Motion was symmetric, and the knee was stable, with negative Lachman and pivot-shift maneuvers. Hardware removal occurred 2 years following index ACL reconstruction, with the patient demonstrating complete resolution of symptoms.

Discussion

As evidenced by the 4 cases presented, iatrogenic iliotibial band syndrome may develop following stable soft tissue allograft ACL reconstruction. All 4 patients had complete symptomatic relief with implant removal. Although rare, this potential complication is likely underreported. Transverse femoral implant prominence may account for idiopathic postoperative knee pain in the stable ACL-reconstructed knee. Progressively increasing pain may be a consequence of implants backing out, while persistent constant pain may result from implants left prominent. Regardless, we believe lateral implant prominence is a preventable complication that is rooted in poor surgical technique.

Femoral fixation with absorbable transverse implant transfixation is one of several available techniques that provides adequate graft fixation for ACL reconstruction.1-7 With this technique, 3- or 5-mm implants measuring 40 or 50 mm can be used to obtain rigid femoral fixation. These implants have been shown to have strength characteristics compatible to withstand normal early rehabilitative exercise regimens.8

Despite this, several device-specific complications with femoral graft fixation have been identified. Intraoperative wire looping can result in fixation failure, wire breakage, or graft laceration.9,10 Postoperative screw fracture can result from bone resorption or pin biodegradation.8,11 Inadvertent intra-articular interference screw placement can lead to postoperative stiffness.12 Screws may back out13 or break,14 causing lateral soft tissue irritation. Specifically, the lateral distal femoral implant can cause iliotibial band syndrome,13,14 which, despite knee stability, can lead to poor clinical outcomes.

The 4 described cases of symptomatic iliotibial band syndrome generated from lateral distal femoral screw prominence developed postoperatively after screw back-out or breakage that occurred months into the normal rehabilitative process.13,14 These cases represent failure likely due to chronic pin and/or bone deformation developed as a result of pin biodegradation and/or local bony resorption. Unlike prior examples demonstrating biologic etiology of iliotibial band syndrome, our 4 cases represent the first described case series identifying screw prominence attributed exclusively to surgical technical error.

In our cases, all patients had progressively increasing activity-related lateral knee pain attributed to lateral screw prominence. Many elements of this iliotibial band syndrome were shared on preoperative physical examination, and improvement was reflected with postoperative complete improvement in all 4 patients. Early clinical identification of iliotibial band syndrome may have been masked by normal postoperative pain, and the progressive nature of the knee pain likely reflected the patients’ reintroduction into normal physical activities during rehabilitation. We believe this confirms the avoidable nature of this potential complication.

As with many complications, avoidance of prominent femoral implant placement is rooted in awareness. We believe efforts to minimize incision length can easily compromise surgical visualization. We encourage clinicians to make incisions large enough to sufficiently allow for digital inspection of the lateral implant in an effort to ensure the lateral edge of the implant is flush with the lateral cortex of the distal femur. Unfortunately, intraoperative fluoroscopy and postoperative radiography can’t confirm implant location, as the radiolucent femoral pin renders these images useless for determination of appropriate hardware placement. Aside from improved visualization, we believe device modification may also help to avoid lateral screw prominence. The inclusion of a radio-opaque market on the lateral tip of the radiolucent femoral implant could additionally assist clinicians with intra- and postoperative radiographic assessment of lateral impingement.

As demonstrated with our 4 patients, treatment with symptomatic hardware removal was curative in all cases. This clinical change was further reflected with an average improvement in postoperative Lysholm value of 38.25±13.5 (Table). We believe hardware removal should only be considered after appropriate normal postoperative ACL reconstructive rehabilitation, with documented clinical ligamentous stability (typically 4-6 months). Premature removal could compromise knee stability prior to normal graft incorporation.

Table 1: Lysholm Scores

Conclusion

With the multitude of technical options available with ACL reconstruction, potential device-specific pitfalls are now being identified in an effort to help clinicians avoid complications. Soft tissue allograft ACL reconstruction is not without exception; lateral femoral implant prominence may lead to iliotibial band syndrome. We believe we have identified a likely underreported and avoidable phenomenon, and we aim to bring greater awareness of this preventable complication to practicing clinicians.

References

  1. Monaco E, Labianca L, Speranza A, et al. Biomechanical evaluation of different anterior cruciate ligament fixation techniques for hamstring graft [published online ahead of print February 12, 2010]. J Orthop Sci. 2010; 15(1):125-131.
  2. Wu JL, Yeh TT, Shen HC, Cheng CK, Lee CH. Mechanical comparison of biodegradable femoral fixation devices for hamstring tendon graft—a biomechanical study in a porcine model [published online ahead of print March 19, 2009]. Clin Biomech (Bristol, Avon). 2009; 24(5):435-440.
  3. Kleweno CP, Jacir AM, Gardner TR, Ahmad CS, Levine WN. Biomechanical evaluation of anterior cruciate ligament femoral fixation techniques [published online ahead of print December 17, 2008]. Am J Sports Med. 2009; 37(2):339-345.
  4. Asik M, Sen C, Tuncay I, Erdil M, Avci C, Taser OF. The mid- to long-term results of the anterior cruciate ligament reconstruction with hamstring tendons using Transfix technique [published online ahead of print May 15, 2007]. Knee Surg Sports Traumatol Arthrosc. 2007; 15(8):965-972.
  5. Milano G, Mulas PD, Ziranu F, Piras S, Manunta A, Fabbriciani C. Comparison between different femoral fixation devices for ACL reconstruction with doubled hamstring tendon graft: a biomechanical analysis. Arthroscopy. 2006; 22(6):660-668.
  6. Rose T, Hepp P, Venus J, Stockmar C, Josten C, Lill H. Prospective randomized clinical comparison of femoral transfixation versus bioscrew fixation in hamstring tendon ACL reconstruction—a preliminary report [published online ahead of print February 8, 2006]. Knee Surg Sports Traumatol Arthrosc. 2006; 14(8):730-738.
  7. Capuano L, Hardy P, Longo UG, Denaro V, Maffulli N. No difference in clinical results between femoral transfixation and bio-interference screw fixation in hamstring tendon ACL reconstruction. A preliminary study [published online ahead of print March 25, 2008]. Knee. 2008; 15(3):174-179.
  8. Golant A, Strauss EJ, Khajavi K, Sherman OH, Rosen JE. Can the Bio-Transfx pin fail during initial ACL graft insertion? Bull NYU Hosp Jt Dis. 2009; 67(4):334-336.
  9. Jaberi FM, Haghighat A, Babanezhad Z, Jaberi MM. Arthroscopic anterior cruciate ligament reconstruction with modified “wireless” cross-screw transfix femoral fixation [published online ahead of print February 12, 2010]. Knee Surg Sports Traumatol Arthrosc. 2010; 18(11):1508-1510.
  10. Choi NH, Son KM, Victoroff BN. A pitfall of transfix fixation during anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2008; 16(5):479-481.
  11. Cossey AJ, Kalairajah Y, Morcom R, Spriggins AJ. Magnetic resonance imaging evaluation of biodegradable transfemoral fixation used in anterior cruciate ligament reconstruction. Arthroscopy. 2006; 22(2):199-204.
  12. Misra R, Strover A, El-Shazly M. Intra-articular protrusion of malpositioned Transfix implant following anterior cruciate ligament reconstruction. Arthroscopy. 2006; 22(2):226.e1-226.e4.
  13. Kokkinakis M, Ashmore A, El-Guindi M. Intraoperative complications using the Bio-Transfix femoral fixation implant in anterior cruciate ligament reconstruction [published online ahead of print September 29, 2009]. Arch Orthop Trauma Surg. 2010; 130(3):375-379.
  14. Pelfort X, Monllau JC, Puig L, Cáceres E. Iliotibial band friction syndrome after anterior cruciate ligament reconstruction using the transfix device: report of two cases and review of the literature [published online ahead of print December 21, 2005]. Knee Surg Sports Traumatol Arthrosc. 2006; 14(6):586-589.

Authors

Drs Argintar, Jordan, and Klimkiewicz and Mr Scherer are from Georgetown University Hospital, Washington, District of Columbia.

Drs Argintar, Jordan, and Klimkiewicz and Mr Scherer have no relevant financial relationships to disclose.

Correspondence should be addressed to: Evan Argintar, MD, Georgetown University Hospital, 3629 38th St NW #304, Washington, DC 20016 (evanargintar@hotmail.com).

doi: 10.3928/01477447-20101021-29

Sign up to receive

Journal E-contents