Knee Surg Sports Traumatol Arthrosc DOI 10.1007/s00167-014-3277-x
KNEE
Meniscal integrity predicts laxity of anterior cruciate ligament reconstruction Curtis Robb · Peter Kempshall · Alan Getgood · Hayley Standell · Andrew Sprowson · Peter Thompson · Tim Spalding
Received: 17 March 2014 / Accepted: 26 August 2014 © European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2014
Abstract Purpose The aim of this study was to evaluate the incidence of failure of anterior cruciate ligament (ACL) reconstruction and to assess the prognostic factors for such an outcome. Methods A prospective inception cohort of patients undergoing ACL reconstruction was analysed for failure (patient reported symptoms of rotational instability, a clinically positive pivot shift, MRI or arthroscopy showing ACL graft rupture). Risk factors evaluated included medial and lateral meniscal deficiency, medial and lateral meniscal repair, age, gender, BMI, graft size and time to surgery. Survival analysis was performed using the Kaplan–Meier method. Prognostic factors were assessed using the Cox proportional hazard model to investigate whether covariate risk factors influenced graft survival. Results One hundred and twenty-three patients were available for final analysis at a follow-up of 2 years. Eighteen patients satisfied the criteria of failure (15.4 %). Risk factors for failure were medial meniscal deficiency (hazard ratio 4.5; 95 % CI 1.8–11.5; p = 0.002), or lateral meniscal deficiency (hazard ratio 3.5; 95 % CI 1.3–9.3; p = 0.01). At 2-year follow-up, ACL survival was 94.5 % (95 % CI 89–100) for patients with intact menisci and 69 % (95 % CI 56–86) for those with deficiency of the medial or lateral meniscus (log-rank test p = 0.017). Patients were 4.9 times C. Robb (*) · P. Kempshall · H. Standell · A. Sprowson · P. Thompson · T. Spalding University Hospital Coventry and Warwickshire NHS Trust, Clifford Bridge Road, Coventry, West Midlands CV2 2DX, UK e-mail: [email protected] A. Getgood Fowler Kennedy Sport Medicine Clinic, 3M Centre, University of Western Ontario, London, Ontario, Canada
more likely to fail if they had a deficient medial or lateral meniscus. Those patients who underwent meniscal repair did not demonstrate any increased risk of failure. Conclusion Medial and lateral meniscal tears are important prognostic factors that influence the survival of ACL reconstruction. Surgeons should endeavour to repair all meniscal tears associated with ACL reconstruction. Level of evidence II. Keywords Anterior cruciate ligament · Meniscus · Risk factors
Introduction Studies on anterior cruciate ligament (ACL) reconstruction, using differing criteria, report failure to be between 3 and 6 % [22, 24, 26, 31]. However, poor results of ACL reconstruction have been difficult to quantify in the literature perhaps because there is no strict definition of failure [13]. Revision ACL reconstruction might be deemed failure, but not all patients with an insufficient ACL reconstruction go on to have further surgery. A much higher percentage of inferior results are seen after ACL surgery if those patients still with a positive pivot shift are included as a poor or failed result. For instance, the Danish Ligament Registry and an ACL meta-analysis report a residual positive pivot shift of 19–24 % [5, 24]. One reason suggested for residual pivot shift after ACL reconstruction has been reported to be surgical technique [10]. The trans-tibial technique based on the concept of graft isometry throughout flexion [6] places the graft anterior to the native ACL attachment site, high in the notch towards the antero-medial bundle position or out of the native femoral ACL attachment site, unless compromise is
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made to the tibial tunnel placement [1]. This creates a graft with postero-lateral to antero-medial bundle mismatch, which can vertically orientate the ACL reconstruction [1, 4, 9, 10], and consequently, the combined rotation and translation movement of the pivot shift phenomenon may not be controlled adequately [10]. Biomechanically, knee kinematics and rotational stability have been more reliably restored with location of the femoral tunnel in the mid-bundle location rather than the trans-tibial technique [4]. Femoral tunnel drilling by the antero-medial portal aims to provide the ability to independently position the ACL graft on the lateral femoral condyle in a place where the surgeon deems it to be the most appropriate position. Nevertheless, the antero-medial portal technique as compared to the trans-tibial technique has also been reported to have a higher failure rate after ACL reconstruction [24]. Although whether this finding could be due to an initial learning curve or represent improved outcome for the transtibial technique is open to debate. More recent comparison of the antero-medial portal and trans-tibial technique in the Danish Ligament Registry failed to show any significant difference in failure (Lind, personal communication). Since 2009, to avoid residual pivot shift, surgeons from this institution have aimed to place the femoral tunnel in the mid-bundle location [6]. Other than changes to surgical techniques, there are other reasons ACL surgery may fail, and these have been related to many different risk factors. Those intrinsic to the patient are younger age, female gender, higher body weight and meniscal injury, others can be influenced by surgery such as time to surgery, femoral and tibial tunnel mal-position, roof impingement, inadequate graft fixation, medial or lateral meniscal repair or graft diameter
KNEE
Meniscal integrity predicts laxity of anterior cruciate ligament reconstruction Curtis Robb · Peter Kempshall · Alan Getgood · Hayley Standell · Andrew Sprowson · Peter Thompson · Tim Spalding
Received: 17 March 2014 / Accepted: 26 August 2014 © European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2014
Abstract Purpose The aim of this study was to evaluate the incidence of failure of anterior cruciate ligament (ACL) reconstruction and to assess the prognostic factors for such an outcome. Methods A prospective inception cohort of patients undergoing ACL reconstruction was analysed for failure (patient reported symptoms of rotational instability, a clinically positive pivot shift, MRI or arthroscopy showing ACL graft rupture). Risk factors evaluated included medial and lateral meniscal deficiency, medial and lateral meniscal repair, age, gender, BMI, graft size and time to surgery. Survival analysis was performed using the Kaplan–Meier method. Prognostic factors were assessed using the Cox proportional hazard model to investigate whether covariate risk factors influenced graft survival. Results One hundred and twenty-three patients were available for final analysis at a follow-up of 2 years. Eighteen patients satisfied the criteria of failure (15.4 %). Risk factors for failure were medial meniscal deficiency (hazard ratio 4.5; 95 % CI 1.8–11.5; p = 0.002), or lateral meniscal deficiency (hazard ratio 3.5; 95 % CI 1.3–9.3; p = 0.01). At 2-year follow-up, ACL survival was 94.5 % (95 % CI 89–100) for patients with intact menisci and 69 % (95 % CI 56–86) for those with deficiency of the medial or lateral meniscus (log-rank test p = 0.017). Patients were 4.9 times C. Robb (*) · P. Kempshall · H. Standell · A. Sprowson · P. Thompson · T. Spalding University Hospital Coventry and Warwickshire NHS Trust, Clifford Bridge Road, Coventry, West Midlands CV2 2DX, UK e-mail: [email protected] A. Getgood Fowler Kennedy Sport Medicine Clinic, 3M Centre, University of Western Ontario, London, Ontario, Canada
more likely to fail if they had a deficient medial or lateral meniscus. Those patients who underwent meniscal repair did not demonstrate any increased risk of failure. Conclusion Medial and lateral meniscal tears are important prognostic factors that influence the survival of ACL reconstruction. Surgeons should endeavour to repair all meniscal tears associated with ACL reconstruction. Level of evidence II. Keywords Anterior cruciate ligament · Meniscus · Risk factors
Introduction Studies on anterior cruciate ligament (ACL) reconstruction, using differing criteria, report failure to be between 3 and 6 % [22, 24, 26, 31]. However, poor results of ACL reconstruction have been difficult to quantify in the literature perhaps because there is no strict definition of failure [13]. Revision ACL reconstruction might be deemed failure, but not all patients with an insufficient ACL reconstruction go on to have further surgery. A much higher percentage of inferior results are seen after ACL surgery if those patients still with a positive pivot shift are included as a poor or failed result. For instance, the Danish Ligament Registry and an ACL meta-analysis report a residual positive pivot shift of 19–24 % [5, 24]. One reason suggested for residual pivot shift after ACL reconstruction has been reported to be surgical technique [10]. The trans-tibial technique based on the concept of graft isometry throughout flexion [6] places the graft anterior to the native ACL attachment site, high in the notch towards the antero-medial bundle position or out of the native femoral ACL attachment site, unless compromise is
13
made to the tibial tunnel placement [1]. This creates a graft with postero-lateral to antero-medial bundle mismatch, which can vertically orientate the ACL reconstruction [1, 4, 9, 10], and consequently, the combined rotation and translation movement of the pivot shift phenomenon may not be controlled adequately [10]. Biomechanically, knee kinematics and rotational stability have been more reliably restored with location of the femoral tunnel in the mid-bundle location rather than the trans-tibial technique [4]. Femoral tunnel drilling by the antero-medial portal aims to provide the ability to independently position the ACL graft on the lateral femoral condyle in a place where the surgeon deems it to be the most appropriate position. Nevertheless, the antero-medial portal technique as compared to the trans-tibial technique has also been reported to have a higher failure rate after ACL reconstruction [24]. Although whether this finding could be due to an initial learning curve or represent improved outcome for the transtibial technique is open to debate. More recent comparison of the antero-medial portal and trans-tibial technique in the Danish Ligament Registry failed to show any significant difference in failure (Lind, personal communication). Since 2009, to avoid residual pivot shift, surgeons from this institution have aimed to place the femoral tunnel in the mid-bundle location [6]. Other than changes to surgical techniques, there are other reasons ACL surgery may fail, and these have been related to many different risk factors. Those intrinsic to the patient are younger age, female gender, higher body weight and meniscal injury, others can be influenced by surgery such as time to surgery, femoral and tibial tunnel mal-position, roof impingement, inadequate graft fixation, medial or lateral meniscal repair or graft diameter
