Matt Daggett

The Involvement of the Anterolateral Ligament in Rotational Control of the Knee

Background: Rotational control of the knee is crucial for knee stability. The anterolateral ligament (ALL) has been identified as a potentially important structure involved in rotational control of the knee. Purpose/Hypothesis: The purpose of this study was to determine, utilizing a navigation system, the involvement of the anterior cruciate ligament (ACL), the iliotibial band (ITB), and the ALL in tibial internal rotational control of the knee. The hypothesis was that the ALL would be involved in rotational control of the knee at varying degrees of knee flexion. Study Design: Controlled laboratory study. Methods: Twelve fresh-frozen cadaveric knees were tested in internal rotation at 20° and 90° of flexion and then subsequently tested using a simulated pivot-shift test consisting of coupled axial rotation at 30° of flexion. Serial sectioning of the ACL, ALL, and ITB was performed. On the contralateral knee, sectioning was performed in the reverse order. Measurements were collected using a surgical navigation system before and after each sectioning. Results: After ACL sectioning, an incision of the ALL induced a significant increase in internal rotation (+19.2% [P = .0002] at 20°; +21.8% [P = .0029] at 90°) and in coupled axial rotation (+43.0%; P = .0035) compared with the intact knee as well as a significant increase in internal rotation at 90° (+13.4%; P = .009) and in coupled axial rotation (+30.8%; P = .0124) compared with the ACL-deficient knee. After ITB sectioning, an additional ALL section caused a significant increase in internal rotation (+39.0% [P = .002] at 20°; +63.0% [P = .0147] at 90°) and in coupled axial rotation (+59.7%; P = .0003) compared with the intact knee as well as a significant increase in internal rotation at 90° (+14.8%; P = .0067) in comparison to the ITB-deficient knee. Conclusion: The ALL is involved in rotational control of the knee at varying degrees of knee flexion and during a simulated pivot shift. Concomitant to an ACL or ITB transection, sectioning the ALL further increased rotational laxity. Clinical Relevance: This laboratory study demonstrated that the ALL provides rotational control of the knee in combination with the ACL and/or ITB.

Anterolateral Ligament Reconstruction Is Associated With Significantly Reduced ACL Graft Rupture Rates at a Minimum Follow-up of 2 Years: A Prospective Comparative Study of 502 Patients From the SANTI Study Group:

Background: Graft failure and low rates of return to sport are major concerns after anterior cruciate ligament (ACL) reconstruction, particularly in a population at risk. Purpose: To evaluate the association between reconstruction techniques and subsequent graft rupture and return-to-sport rates in patients aged 16 to 30 years participating in pivoting sports. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective study of patients undergoing primary ACL reconstruction with a bone–patellar tendon–bone (B-PT-B) graft, quadrupled hamstring tendon (4HT) graft, or hamstring tendon graft combined with anterolateral ligament reconstruction (HT+ALL) was conducted by the Scientific ACL NeTwork International (SANTI) Study Group. Survivorship data from Kaplan-Meier analysis were analyzed in multivariate Cox regression models to identify the prognosticators of graft ruptures and return to sport. Results: Five hundred two patients (mean age, 22.4 ± 4.0 years) with a mean follow-up of 38.4 ± 8.5 months (range, 24-54 months) were included. There were 105 B-PT-B, 176 4HT, and 221 HT+ALL grafts. The mean postoperative scores at latest follow-up were the following: Lysholm: 92.4 ± 8.6, Tegner: 7.4 ± 2.1, and subjective International Knee Documentation Committee (IKDC): 86.8 ± 10.5 for B-PT-B grafts; Lysholm: 91.3 ± 9.9, Tegner: 6.6 ± 1.8, and subjective IKDC: 85.4 ± 10.4 for 4HT grafts; and Lysholm: 91.9 ± 10.2, Tegner: 7.0 ± 2.0, and subjective IKDC: 81.8 ± 13.1 for HT+ALL grafts. The mean side-to-side laxity was 0.6 ± 0.9 mm for B-PT-B grafts, 0.6 ± 1.0 mm for 4HT grafts, and 0.5 ± 0.8 mm for HT+ALL grafts. At a mean follow-up of 38.4 months, the graft rupture rates were 10.77% (range, 6.60%-17.32%) for 4HT grafts, 16.77% (range, 9.99%-27.40%) for B-PT-B grafts, and 4.13% (range, 2.17%-7.80%) for HT+ALL grafts. The rate of graft failure with HT+ALL grafts was 2.5 times less than with B-PT-B grafts (hazard ratio [HR], 0.393; 95% CI, 0.153-0.953) and 3.1 times less than with 4HT grafts (HR, 0.327; 95% CI, 0.130-0.758). There was no significant difference in the graft failure rate between 4HT and B-PT-B grafts (HR, 1.204; 95% CI, 0.555-2.663). Other prognosticators of graft failure included age ≤25 years (P = .012) and a preoperative side-to-side laxity >7 mm (P = .018). The HT+ALL graft was associated with higher odds of returning to preinjury levels of sport than the 4HT graft (odds ratio [OR], 1.938; 95% CI, 1.174-3.224) but not compared with the B-PT-B graft (OR, 1.460; 95% CI, 0.813-2.613). Conclusion: In a high-risk population of young patients participating in pivoting sports, the rate of graft failure with HT+ALL grafts was 2.5 times less than with B-PT-B grafts and 3.1 times less than with 4HT grafts. The HT+ALL graft is also associated with greater odds of returning to preinjury levels of sport when compared with the 4HT graft.

Minimally Invasive Anterolateral Ligament Reconstruction in the Setting of Anterior Cruciate Ligament Injury

Recent evidence on the anatomy, function, and biomechanical properties of the anterolateral ligament has led to the recognition of the importance of this structure in the rotational control of the knee. This article describes a technique that allows for minimally invasive anterolateral ligament reconstruction as a complement to most techniques of anterior cruciate ligament reconstruction. A gracilis tendon autograft is harvested and prepared in a double-strand, inverted V-shaped graft. The graft is percutaneously placed through a femoral stab incision, and each strand is then passed deep to the iliotibial band, emerging through each tibial stab incision. After the femoral-end loop graft is fixed, the tibial fixation of each strand is performed in full extension for optimal isometry.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction

Despite technologic advances in the surgical technique for anterior cruciate ligament (ACL) reconstruction, some patients continue to have rotational instability postoperatively. Recently, authors have reported the anatomic and functional characteristics of the anterolateral ligament (ALL), a structure that originates near the lateral epicondyle on the femur and inserts on the tibia between the Gerdy tubercle and the fibular head. Recent biomechanical studies have shown the ALL is an important stabilizer against anterolateral tibial rotation, and its reconstruction has shown excellent initial clinical results. Several techniques have been developed to try to anatomically address this structure in the setting of an ACL reconstruction. This article details a simple anatomic technique to reconstruct the ACL and the ALL of the knee using hamstring tendon autograft and maintaining the semitendinosus insertion.

The Role of the Anterolateral Structures and the ACL in Controlling Laxity of the Intact and ACL-Deficient Knee: Letter to the Editor

Dear Editor: We read with significant interest the article by Kittl et al on the role of the anterolateral structures in controlling laxity of the intact and anterior cruciate ligament (ACL)–deficient knee. We congratulate the authors on this interesting study, which contributes further to our understanding of the role of these anatomic structures. However, we would like to bring up some important questions and remarks related to this paper. First, has the dissection technique utilized in this study been previously validated? How did the authors confirm that they were isolating the deep iliotibial band (ITB) from the superficial ITB? Similarly, the isolation of the anterolateral ligament (ALL) performed in this study has never, to our knowledge, been performed in this way. How did the authors ensure that the deep capsule-osseous layer and the ALL were completely separated in their entirety? Was histologic analysis subsequently performed to ensure that each structure tested was as described? The ALL described in the article and illustrated in Figure 3 is visually quite different from the structure described in previous publications. The ALL depicted in Figure 3 of this article appears significantly smaller, with an attachment that appears to be adjacent to the joint line of the tibia, above the tibial landmarks previously described. Furthermore, the anatomic depiction lacks the fanlike insertion on the tibia that has been widely published. In addition, Figure 2B of the Kittl et al article demonstrates the knee after resection of the capsule-osseous layer of the ITB, prior to isolation of the ALL, yet there does not appear to be any distinguishable structure remaining, certainly not the presence of a robust ALL. We know that the dissection technique utilized contributes significantly to the interpretation of the characteristics of these anterolateral structures, specifically the ALL, and that this interpretation also alters the biomechanical characteristics of these structures. A review of articles by Kaplan and Terry et al reveals the historical challenge in defining these structures. It is interesting, however, that Terry et al describe the capsule-osseous layer of the deep ITB as a structure ‘‘whose proximal origin is continuous with fascia covering the plantaris and lateral gastrocnemius and whose tibial insertion is just posterior to the Gerdy tubercle.’’ Furthermore, Terry et al describe this structure as acting as if it is ‘‘an anterolateral ligament of the knee’’ (Figure 1). We postulate that perhaps the ‘‘deep capsulo-osseous layer of the ITB’’ referenced by Terry et al and the ALL of the knee are generally the same structure, just dissected with different techniques. Current literature clearly demonstrates that directly underneath the ‘‘superficial’’ ITB lies the ALL, as demonstrated not only by the dissection technique from Daggett et al but also by magnetic resonance imaging studies showing that the ALL runs inferior to the ITB with no other distinguishable structure between them. Additionally, we know that this structure is histologically an extracapsular ligament and is involved in rotational control of the knee. The correlation between the ALL and the ‘‘capsulo-osseous layer of the ITB’’ as described by Terry et al is further supported by biomechanical findings. When the findings of this study by Kittl et al are compared with those of other studies examining the role of the ALL in internal rotation control of the tibia, the results are quite similar if one considers the structures to be the same. Regardless of name, we are now all in agreement that an anatomic structure, deep to the superficial ITB that inserts posterior to the Gerdy tubercle, plays a significant role in controlling internal rotation of the knee. Furthermore, while the authors found a significant contribution of the ‘‘superficial’’ ITB to stability of the knee, we believe that these laboratory findings do not translate clinically. In the setting of acute ACL tear, one rarely encounters an injury to the ITB. Additionally, although the authors found the different structures contributing to rotation at varying degrees of flexion, physiologic motion of the knee in its entirety is what is important, and this motion is limited internal rotation toward knee extension (ie, 15 ) with significantly more physiologic rotation in deeper degrees of knee flexion (ie, 90 ). Figure 1. The capsulo-osseous layer of the iliotibial band as described by Terry et al demonstrates significant similarity to the anterolateral ligament as described by Claes et al. (Reprinted with permission from Terry et al. 1986, American Orthopaedic Society for Sports Medicine.)

Surgical Management of Recurrent Musculotendinous Hamstring Injury in Professional Athletes.

Background: Hamstring injury is the most common muscular lesion in athletes. The conservative treatment is well described, and surgical management is often indicated for proximal tendinous avulsions. To our knowledge, no surgical treatment has been proposed for failure of conservative treatment in musculotendinous hamstring lesions. Purpose: To describe the surgical management of proximal and distal hamstring musculotendinous junction lesions in professional athletes after failure of conservative treatment. Study Design: Case series; Level of evidence, 4. Methods: A consecutive series of 10 professional athletes, including 4 soccer players, 4 rugby players, and 2 handball players, underwent surgical intervention between October 2010 and June 2014 for the treatment of recurrent musculotendinous hamstring injuries. All athletes had failed at least 3 months of conservative treatment for a recurrent musculotendinous hamstring injury. Surgical resection of the musculotendinous scar tissue was performed using a longitudinal muscular suture. Lower Extremity Functional Scale (LEFS) and Marx scores were obtained at the 3-month follow-up, and a final phone interview was completed to determine recurrence of hamstring injury and return to previous level of play. Results: The mean age at surgery was 25.2 years (range, 19-35 years). The musculotendinous hamstring lesions involved 8 semitendinosus and 2 biceps femoris, with 6 injuries located proximally and 4 distally. Conservative treatment lasted a mean 5.1 months (range, 3-9 months) after last recurrence, and the patients had an average of 2.7 (range, 2-5) separate incidents of injury recurrence before surgical intervention was decided upon. At the 3-month follow-up, all patients had Marx activity scores of 16 and LEFS scores of 80. All 10 patients returned to the same level of play at a mean 3.4 months (range, 2-5 months). At a mean follow-up of 28.7 months, none of the athletes had suffered a recurrence. No surgical complication was encountered. Conclusion: In cases of failed conservative treatment of musculotendinous hamstring lesions, surgical intervention may be a viable treatment option in professional athletes and allows the patient to return to the same level of play.

Anatomic Anterolateral Ligament Reconstruction Leads to Overconstraint at Any Fixation Angle: Letter to the Editor

Dear Editor: We read with significant interest the article by Schon et al on the effect of the anterolateral ligament (ALL) reconstruction graft fixation angle on knee joint kinematics in the presence of a concomitant anterior cruciate ligament (ACL) reconstruction. In their navigated cadaveric study, the authors tested an anatomic ALL reconstruction using graft fixation angles of 0 , 15 , 30 , 45 , 60 , 75 , and 90 concomitant with an ACL reconstruction. Internal rotation, anterior translation, axial plane translation, and internal rotation during a simulated pivot-shift test were recorded. Kinematic changes were measured and compared with the intact state for all reconstructed and sectioned states with a 6 degrees of freedom robotic system. The authors found that ‘‘anatomic ALLR at all graft fixation angles significantly overconstrained internal rotation of the knee joint beyond 30 of flexion and at 45 and 60 during the pivot-shift test.’’ The authors concluded that ‘‘ALLR at any fixation angle overconstrained native joint kinematics and should be performed with careful consideration.’’ In their protocol, the authors anatomically reconstructed the ALL and arbitrarily applied an 88-N traction force for its fixation. The details of their results indicate that for an ALL graft fixed in full extension compared with an intact knee, the mean maximum overconstraint was 2.8 at 120 of flexion after an internal rotation torque, 2.2 at 60 of flexion in an internal rotation, and 1.2 at 45 of flexion in an axial translation during a simulated pivot shift. We must ask two questions: Would the authors have obtained the same results with less tension on the ALL graft? Eighty-eight newtons of force is a significant force that likely does not mimic physiologic knee motion. Additionally, even at this high, extraphysiologic force, what are the clinical ramifications of 1 to 2 of overconstraint? Moreover, their study fails to reproduce the real clinical and biomechanical consequence of an ACL rupture. In their review of literature, Noyes and Barber-Westin reported that 60% of meniscal lesions were concomitant with ACL tears in 19,531 patients. Study also suggests that meniscocapsular lesions will allow abnormal tibiofemoral laxity. Furthermore, an isolated ACL tear was reported to be a rare phenomenon and was noted in only 12% of the cases in an MRI study of 1145 cases; ACL tear occurred in combination with other ligament injuries, meniscal tears, cortical depression fractures, or osteochondral fractures in 88% of cases. Would the Schon et al have obtained the same results with such concomitant injuries? In their discussion, Schon et al reported high failure rates, long-term chronic pain and/or swelling, lower subjective and objective results, and poor long-term functional results after lateral extra-articular (LET) procedures. They also reported that adding LET to an intra-articular ACL reconstruction provided no significant benefits and that LET demonstrated internal tibial rotation overconstraint. All of the clinical studies cited were published more than 10 years ago and were based on nonanatomic LET procedures using mostly an iliotibial band strand under the lateral collateral ligament, fixed in flexion and often with the tibia in external rotation. Moreover, the postoperative rehabilitation protocol was completely different in these early studies. The best answer to this ongoing biomechanical controversy is found in our clinical results. Based on our clinical experience with several hundred combined ACL and ALL reconstructions, we do not believe that the concerns raised about overconstraint of the knee are valid with anatomic ALL reconstruction performed with the graft fixed in full extension and in neutral rotation. With a 5-year followup, we have found no clinical evidence of overconstraint or stiffness and we have not performed one reoperation to cut a tight ALL. Given our results of combined ACL and ALL reconstruction compared with traditional ACL reconstruction with regard to rerupture rate, return to play, and rotational stability, we extended massively our combined ALL indications in nearly 70% of our patients. Initially, our indications included the presence of a pivot shift on examination, a Segond fracture identified on preoperative radiography, and revision ACL cases. Because of our early success, we have now expanded our indications to include participation in pivoting athletics, female patients, hyperlaxity, and patients younger than 25 years. Our clinical results, which are very promising in retrospective study, should be confirmed in a prospective randomized study. In conclusion, we value the biomechanical findings of the article by Schon et al but disagree with the conclusions and extrapolations in regard to clinical reconstruction of the ALL. Biomechanical studies provide new insights and are important for sports medicine and orthopaedic surgeons. However, these cadaveric studies in isolation should be very cautiously interpreted and cannot be used to either verify or discount a surgical procedure.

The Anterolateral Ligament: An Anatomic Study on Sex-Based Differences

Background: The anterolateral ligament (ALL) has been shown to have an important role in rotatory stability of the knee. While there is abundant research on sex-based differences related to anterior cruciate ligament (ACL) rupture, there is a paucity of literature related to such differences in the ALL. Purpose: To define any sex-based differences in the ALL with regard to length, width, and thickness. Study Design: Descriptive laboratory study. Methods: The ALL was initially evaluated in 165 unpaired knees (92 males and 65 females after exclusion criteria applied). The length, width, and thickness of the ALL were measured using a digital caliper. Width and thickness were measured at the joint line just superior to the lateral meniscus. The Mann-Whitney test and Student t tests were used to compare measurements between males and females. The Pearson product-moment correlation was subsequently used to determine the correlation between height and weight and the statistically different morphometric variables. Results: The mean (±SD) thickness of the ALL in males was 2.09 ± 0.56 mm, almost twice as thick as females (1.05 ± 0.49 mm; P = 8.8 × 10−20). There was also a statistically significant difference in ALL length (P = 3.8 × 10−7), but no significant difference was found for width. A moderate association was found between donor height and ALL thickness and length. Conclusion: The anatomic measurements of the ALL demonstrate a difference between sexes, and the ALL is significantly thicker in males than females. Clinical Relevance: As the role of the ALL in rotatory stability of the knee becomes better understood, the difference in the thickness of the ALL we have found between the sexes may be another factor why female athletes have an increased incidence of ACL rupture compared with males. This may also help explain why females have issues with knee laxity and rotatory instability.

Hamstring Contracture After ACL Reconstruction Is Associated With an Increased Risk of Cyclops Syndrome

Background: Cyclops syndrome is characterized by loss of terminal knee extension due to proliferative fibrous nodule formation in the intercondylar notch. This complication occurs in the early postoperative period after anterior cruciate ligament reconstruction (ACLR). The pathogenesis of Cyclops syndrome is not well understood. Hypothesis: Persistent hamstring contracture after ACLR is associated with an increased risk of subsequent Cyclops syndrome. Study Design: Case-control study; Level of evidence, 3. Methods: The files of 45 patients who underwent arthroscopic debridement of a Cyclops lesion after ACLR were analyzed. Recorded data included demographic information and technical details of surgery. Preoperative magnetic resonance images were also analyzed, and patients with femoral bone bruising were identified. Passive and active range of motion were recorded in all patients preoperatively and at 3 and 6 weeks after surgery to address the Cyclops lesion. Passive extension deficit was evaluated in comparison with the contralateral limb and classified as secondary to hamstring contracture when contracture was observed and palpated in the prone position and when the extension deficit was reversed after exercises performed to fatigue the hamstrings. A control group was selected using a random numbers table among our entire ACLR cohort. Statistical analysis was performed to analyze differences between the 2 groups. Results: There was no significant difference between the groups with regard to age at ACLR, sex distribution, time from injury to surgery (P > .05), proportion of professional athletes, presence of femoral bone bruise, or technical aspects of surgery. The overall extension deficit incidence was significantly higher in the Cyclops group at 3 weeks (Cyclops, 71%; control, 22%) (P < .001) and at 6 weeks (Cyclops, 60%; control, 7%) (P < .001). The extension deficit related to hamstring contracture was significantly higher in the Cyclops group at 3 weeks (Cyclops, 58%; control, 22%) (P < .001) and at 6 weeks (Cyclops, 29%; control, 2%) (P < .001). Conclusion: The Cyclops lesion is associated with a persistent hamstring contracture at 3 and 6 weeks after ACLR.

Anterolateral Ligament Reconstruction Protects the Repaired Medial Meniscus: A Comparative Study of 383 Anterior Cruciate Ligament Reconstructions From the SANTI Study Group With a Minimum Follow-up of 2 Years:

Background: The prevalence of osteoarthritis after successful meniscal repair is significantly less than that after failed meniscal repair. Purpose: To determine whether the addition of anterolateral ligament reconstruction (ALLR) confers a protective effect on medial meniscal repair performed at the time of anterior cruciate ligament reconstruction (ACLR). Study Design: Cohort study; Level of evidence, 3. Methods: Retrospective analysis of prospectively collected data was performed to include all patients who had undergone primary ACLR with concomitant posterior horn medial meniscal repair through a posteromedial portal between January 2013 and August 2015. ACLR autograft choice was bone–patellar tendon–bone, hamstring tendons (or quadrupled hamstring tendons), or quadrupled semitendinosus tendon graft with or without ALLR. At the end of the study period, all patients were contacted to determine if they had undergone reoperation. A Kaplan-Meier survival curve was plotted, and a Cox proportional hazards regression model was used to perform multivariate analysis. Results: A total of 383 patients (mean ± SD age, 27.4 ± 9.2 years) were included with a mean follow-up of 37.4 months (range, 24-54.9 months): 194 patients underwent an isolated ACLR, and 189 underwent a combined ACLR + ALLR. At final follow-up, there was no significant difference between groups in postoperative side-to-side laxity (isolated ACLR group, 0.9 ± 0.9 mm [min to max, –1 to 3]; ACLR + ALLR group, 0.8 ± 1.0 mm [min to max, –2 to 3]; P = .2120) or Lysholm score (isolated ACLR group, 93.0 [95% CI, 91.3-94.7]; ACLR + ALLR group, 93.7 [95% CI, 92.3-95.1]; P = .556). Forty-three patients (11.2%) underwent reoperation for failure of the medial meniscal repair or a new tear. The survival rates of meniscal repair at 36 months were 91.2% (95% CI, 85.4%-94.8) in the ACLR + ALLR group and 83.8% (95% CI, 77.1%-88.7%; P = .033) in the ACLR group. The probability of failure of medial meniscal repair was >2 times lower in patients with ACLR + ALLR as compared with patients with isolated ACLR (hazard ratio, 0.443; 95% CI, 0.218-0.866). No other prognosticators of meniscal repair failure were identified. Conclusion: Combined ACLR and ALLR is associated with a significantly lower rate of failure of medial meniscal repairs when compared with those performed at the time of isolated ACLR.