Popliteofibular Ligament Reconstruction Research Articles

Posterior Cruciate Ligament and Posterolateral Corner Reconstruction: Clinical Outcomes Following Popliteal Tendon Tenodesis and Popliteal Tendon Reconstruction.

Injuries to the posterolateral compartment (PLC) of the knee require special attention, as incorrect diagnosis and treatment may lead to considerable morbidity. However, no gold standard treatment has been established for PLC injuries. 38 patients with concomitant (posterior cruciate ligament (PCL) and PLC injuries were divided into two groups according to surgical treatment of the proximal popliteal tendon injury. They were treated with anatomic popliteal tendon, lateral collateral ligament (LCL), and popliteofibular ligament (PFL) reconstruction (group 1; n = 19) and were treated with popliteal tendon tenodesis, LCL, and PFL reconstruction (group 2; n = 19). The Lysholm score, dial test, and lateral compartment opening on varus stress X-ray were used as outcome measurements evaluated before surgery and at 6, 12, and 24months of follow-up. Overall, there was a progressive improvement in the Lysholm score and the lateral opening on varus stress radiography during the evaluated periods for both groups (p < 0.001). Patients from group 2 recorded better Lysholm scores than those from group 1 at 12- and 24-month follow-up (p = 0.02). Dial test was negative in all patients after 6, 12, and 24months. Patients with popliteal tendon tenodesis were found to have better Lysholm scores than patients with reconstruction after 12 and 24months of follow-up. There was no difference in the lateral joint opening evaluated by stress radiography between groups. These results show that tenodesis could be a viable treatment option for lateral femoral condyle popliteal disruptions in the context of PLC and PCL combined injuries, and should be considered in the surgical planning process.

Posterolateral Corner Reconstruction of the Knee Using Gracilis Autograft and Biceps Femoris

We introduce our technique for posterolateral corner reconstruction, which is based on the principle described in Arciero’s technique for anatomic reconstruction of lateral collateral ligament (LCL) and popliteofibular ligament (PFL) to gain static stability in varus strain and external rotation. This technique uses a doubled gracilis autograft to reconstruct the PFL and a split biceps tendon transfer to reconstruct the LCL. Using this technique an anatomical LCL and PFL reconstruction can be performed in combination with anterior cruciate ligament or posterior cruciate ligament reconstruction without contralateral graft harvest or allograft. The technique also enables an isolated reconstruction of LCL or PFL when required and can be performed to augment an acute repair.

Comparison of Anatomic Posterolateral Knee Reconstruction Using 2 Different Popliteofibular Ligament Techniques

Background: Anatomic posterolateral knee reconstruction is a surgical procedure that reconstructs the lateral collateral ligament (LCL), the popliteus tendon, and the popliteofibular ligament (PFL). Until recently, diverse techniques have been reported for this reconstruction; however, the gold standard is still a matter of debate. Hypothesis: Clinical outcomes and stability with tibiofibular-based PFL reconstruction would be better than those with femorofibular-based PFL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: The records of 10 patients who underwent anatomic posterolateral knee reconstruction between January 2011 and December 2012 (LCL, popliteus tendon, tibiofibular-based PFL reconstruction [group A]) with a minimum follow-up of 24 months were retrospectively reviewed. Ten patients who underwent anatomic posterolateral knee reconstruction (LCL, popliteus tendon, femorofibular-based PFL reconstruction [group B]) using a split Achilles tendon allograft were recruited into a matched control group. All patients in both groups had an associate posterior cruciate ligament (PCL) injury, and 8 in each group underwent concomitant PCL reconstruction. Clinical outcomes were evaluated with International Knee Documentation Committee (IKDC) subjective, Lysholm, and Tegner activity scale scores. Knee stability was assessed with the dial test for the evaluation of external rotation as well as varus and posterior instability by stress radiography. Results: The mean (±SD) follow-up period was 29.5 ± 3.8 months in group A and 60.4 ± 33.8 months in group B. There were no clinically significant between-group differences in IKDC subjective scores (group A: 83.8 ± 5.4, group B: 82.7 ± 6.5; P = .853), Lysholm scores (group A: 83.4 ± 5.1, group B: 84.1 ± 7.3; P = .853), or Tegner activity scale scores (group A: 4.8 ± 1.4, group B: 4.2 ± 0.9; P = .436) at the final follow-up. In addition, there was no difference in side-to-side measurements on varus stress radiography (group A: 0.9 ± 0.7 mm, group B: 1.3 ± 1.2 mm; P = .481) or posterior stress radiography (group A: 5.3 ± 1.9 mm, group B: 5.4 ± 2.2 mm; P = .971) at the final follow-up. Although the external rotation grade of the tibia was not significantly different between groups preoperatively (P = .709), it was smaller in group A at the final follow-up (P = .044). Conclusion: There were no significant differences in clinical outcomes or varus stability between the 2 techniques of PFL reconstruction in patients with posterolateral corner injuries who underwent anatomic posterolateral knee reconstruction. However, the external rotation grade of the tibia was smaller in the group that underwent tibiofibular-based PFL reconstruction.

Biomechanical comparison of two surgical techniques for press-fit reconstruction of the posterolateral complex of the knee.

To date, various surgical techniques to treat posterolateral knee instability have been described. Recent studies recommended an anatomical and isometric reconstruction of the posterolateral corner addressing the key structures, such as lateral collateral ligament (LCL), popliteus tendon (POP) and popliteofibular ligament (PFL). Two clinical established autologous respective local reconstruction methods of the posterolateral complex were tested for knot-bone cylinder press-fit fixation to assess efficacy of each reconstruction technique in comparison to the intact knee. The knot-bone cylinder press-fit fixation for both anatomic and isometric reconstruction techniques of the posterolateral complex shows equal biomechanical stability as the intact posterolateral knee structures. This was a controlled laboratory study. Two surgical techniques (Larson: fibula-based semitendinosus autograft for LCL and PFL reconstruction/Kawano: biceps femoris and iliotibial tract autograft for LCL, PFL and POP reconstruction) with press-fit fixation were used for restoration of posterolateral knee stability. Seven cadaveric knees (66 ± 3.4 years) were tested under three conditions: intact knee, sectioned state and reconstructed knee for each surgical technique. Biomechanical stress tests were performed for every state at 30° and 90° knee flexion for anterior-posterior translation (60 N), internal-external and varus-valgus rotation (5 Nm) at 0°, 30° and 90° using a kinemator (Kuka robot). At 30° and 90° knee flexion, no significant differences between the four knee states were registered for anterior-posterior translation loading. Internal-external and varus-valgus rotational loading showed significantly higher instability for the sectioned state than for the intact or reconstructed posterolateral structures (p < 0.05). There were no significant differences between the intact and reconstructed knee states for internal-external rotation, varus-valgus rotation and anterior-posterior translation at any flexion angles (p > 0.05). Comparing both reconstruction techniques, significant higher varus-/valgus stability was registered for the fibula-based Larson technique at 90° knee flexion (p < 0.05). Both PLC reconstructions showed equal biomechanical stability as the intact posterolateral knee structures when using knot-bone cylinder press-fit fixation. We registered restoration of the rotational and varus-valgus stability with both surgical techniques. The anterior-posterior translational stability was not influenced significantly. The Larson technique showed significant higher varus/valgus stability in 90° flexion. The latter is easier to perform and takes half the preparation time, but needs grafting of the semitendinosus tendon. The Kawano reconstruction technique is an interesting alternative in cases of missing autografts.

In Vitro Comparison of Popliteus Tendon and Popliteofibular Ligament Reconstruction in an External Rotation Injury Model of the Knee

Background: In posterolateral corner (PLC) injuries in which the lateral collateral ligament (LCL) is intact, there is controversy about whether reconstructing the popliteus tendon (POP), the popliteofibular ligament (PFL), or both structures (POP + PFL) is required to restore normal external tibial rotation. Hypothesis: Three reconstruction techniques, POP, PFL, and POP + PFL, are able to restore external tibial rotation to normal. Study Design: Controlled laboratory study. Methods: Six nonpaired human knees were tested under the following states: POP and PFL intact and sectioned. The 3 different surgical techniques were used to reconstruct the sectioned structures, and the knees were retested. Each knee was subjected to a 5-N·m external rotation torque and tested at 0°, 30°, 45°, 60°, 90°, and 120° of flexion. A navigation system was used to measure motion changes of the tibia with respect to the femur. Results: There were small but significant increases in external rotation after sectioning both the POP and PFL. Sectioning of either one of these structures alone produced smaller increases that were not significant. After comparing all of the tested reconstructed states to the intact state, there were significant differences at knee flexion angles from 30° to 90°. The PFL procedure restored external tibial rotation without significant differences compared with the intact knee at 30° to 90° of flexion. The POP and POP + PFL techniques significantly overconstrained external tibial rotation at all tested angles. Conclusion: In an LCL-intact PLC injury model, the POP and PFL function as a unit in resisting external rotation. All surgical procedures described and tested were able to reduce the increased external rotational laxity found in the sectioned state. The PFL reconstruction technique was able to restore external rotation to near normal. However, the techniques involving POP reconstruction overconstrained external rotation during laxity testing.

The effects of popliteus tendon and popliteofibular ligament reconstruction in an external rotation injury model of the knee

Objective To investigate the effects of the popliteofibular ligament (PFL) and/or the popliteus tendon (POP) reconstruction in an external rotation injury model of the knee.Methods Six nonpaired cadaveric knees were tested under the following POP and PFL states:intact,sectioned,and reconstructed using 3 different techniques.Each knee was subjected to 5 N·m external rotation torque at flexion angles of 0°,30°,45°,60°,90°,and 120°.A navigation system was used to measure the motion changes of the tibia with respect to the femur.Results The external rotation increased 2.1°±0.7° (2.0°-2.3°) after sectioning only PFL while flexing the knee from 30° to 120°,and increased 1.3°±1.2° (0.5°-2.0°) after sectioning only POP while flexing the knee from 30° to 120°.There was no significant difference between two groups.There was significant increase in external rotation as 4.1°±1.6° (2.8°-5.0°) after sectioning both POP and PFL.Comparing the POP and POP+PFL reconstruction techniques to the intact state,there were significant differences.The external tibial rotation in POP or POP+PFL reconstruction group was significant different from that in intact or PFL reconstruction group while flexing the knee from 30° to 90°.Conclusion In a LCL-intact PLC injury model,the POP and PFL function as a unit in resisting external rotation.All surgical procedures we described and tested are able to reduce the increased external rotational laxity found in the sectioned state.The PFL reconstruction is able to restore external rotation to near normal.However the techniques involving POP reconstruction over constrained external rotation during laxity testing. Key words: Knee joint; Joint instability; Biomechanics; Reconstructive surgical procedures

Anatomic Posterolateral Knee Reconstructions Require a Popliteofibular Ligament Reconstruction Through a Tibial Tunnel

Background: No biomechanical study has been performed analyzing the merits of reconstructing the popliteofibular ligament (PFL) through a tibial tunnel with an anatomic reconstruction of the posterolateral knee. Hypothesis: There is no difference in an anatomic posterolateral knee reconstruction with or without a PFL reconstruction placed through a tibial tunnel in restoring knee motion to the intact, uninjured state, and the knee is not overconstrained with this reconstruction. Study Design: Controlled laboratory study. Methods: Eight paired knees were tested in the intact state and then sectioned to simulate a grade III posterolateral knee injury. The reconstruction for the first paired knee reconstructed the PFL (through a tibial tunnel), popliteus tendon, and fibular collateral ligament (group 1); the matched knee reconstruction involved only the popliteus tendon and fibular collateral ligament (group 2). Results: Reconstructions for group 1 knees restored knee motion to the intact state for all tested conditions at all knee flexion angles with no overconstraint of the knee. Without reconstructing the PFL (group 2), small but significant increases in motion were found for varus translation at 0° (3.0°), 20° (3.1°), and 60° (3.8°) of knee flexion compared with the intact state. At 60° and 90° of flexion, the reconstruction for group 2 had small but significant increases in internal rotation compared with the intact state (1.3° and 1.8°, respectively). Conclusion: Inclusion of the PFL through a tibial tunnel as part of an anatomic posterolateral knee reconstruction restores knee stability back to the intact state and does not overconstrain the knee. Furthermore, inclusion of the PFL through a tibial tunnel restored normal internal rotation. Clinical Relevance: The PFL should be included in anatomic reconstructions of grade III posterolateral knee injuries with placement through a tibial tunnel to best restore the intact, preinjury knee motion state and, most notably, normal internal rotation without evidence of overconstraint of the knee.

Single-Bundle Posterior Cruciate Ligament Reconstruction and Mini-Open Popliteofibular Ligament Reconstruction in Knees With Severe Posterior and Posterolateral Rotation Instability: Clinical Results of Minimum 2-Year Follow-up

The aim of this study was to assess the clinical outcome of arthroscopy-assisted posterior cruciate ligament (PCL) reconstruction and mini-open popliteofibular ligament (PFL) reconstruction for severe posterior and posterolateral rotation instability of the knee with lateral collateral ligament intact. Arthroscopic PCL reconstruction and mini-open PFL reconstruction were performed consecutively in 24 patients with chronic posterior and posterolateral rotation instability of the knee. The inclusion criteria for surgery were a side-to-side difference in posterior translation of more than 12 mm measured with stress radiography and tibial external rotation of 10 degrees more than that of the contralateral uninjured knee without varus laxity. The exclusion criterion was combined anterior cruciate ligament injury. The patients underwent single-bundle PCL reconstruction with Achilles tendon allograft. A mini-open PFL reconstruction was performed with anterior tibialis allograft. A 2-cm incision was made on the lateral epicondyle to build the femoral tunnel, and a 3-cm incision was made near the fibular head for the fibular tunnel. The minimum follow up was 2 years. At final follow up, 18 patients (75% [18 of 24]) were enrolled in the study group and 6 patients were lost. Postoperatively, mean posterior tibial translation (side-to-side difference) in our patients was reduced from 17.3 +/- 4.1 mm to 4.6 +/- 3.2 mm. Tibial external rotation was decreased from a mean of 14.7 degrees +/- 4.6 degrees to -2.8 degrees +/- 3.8 degrees, as compared with the contralateral uninjured knee. These differences were statistically significant. The International Knee Documentation Committee grade preoperatively was grade D in all 18 patients, whereas postoperatively, 5 were classified as grade A, 8 as grade B, and 5 as grade C. In this small clinical series, single-bundle PCL reconstruction combined with mini-open PFL reconstruction was proven to correct pathologic excessive posterior and posterolateral rotation instability. Level IV, therapeutic case series (no control or historical group).

Popliteofibular ligament reconstruction for posterolateral external rotation instability of the knee

The aim of this study was to assess the clinical outcome of popliteofibular ligament (PFL) reconstruction for posterolateral external rotation instability of the knee. PFL reconstruction was performed consecutively in 22 patients with chronic external rotation instability of the knee. The inclusion criterion for surgery was tibial external rotation of 10 degrees more than the contralateral uninjured knee without varus laxity. A double bone tunnel was created at the PFL insertion of the fibular head through the lateral incision of the knee joint and a single bone tunnel at the popliteus tendon insertion on the femoral side. A semitendinosus autograft tendon or tibialis anterior allograft tendon was introduced through the fibular tunnel as a loop, then both free ends of the graft were introduced through the femoral tunnel and a bioabsorbable interference screw was used to fix the graft. The minimum follow-up was 2 years. Clinical review included the International Knee Documentation Committee (IKDC) scale and tibial external rotation assessment. All patients' preoperational tibial external rotation averaged 15 degrees more than the contralateral uninjured knee. operatively the tibial external rotation was decreased, average -3 degrees compared with the contralateral side. This difference was statistically significant. The final IKDC grades were: 22 cases with grade D preoperatively, and 6 were grade A, 8 were grade B, 7 were grade C and 1 was grade D postoperatively. In this small clinical series, PFL reconstruction technique was shown to correct pathological excessive tibial external rotation.

Femoral Fixation Sites for Optimum Isometry of Posterolateral Reconstruction*

Graft reconstructions of the lateral collateral ligament, popliteus tendon, and popliteofibular ligament are frequently performed in conjunction with a reconstruction of the posterior cruciate ligament to restore knee stability. The purpose of this study was to determine the femoral fixation sites resulting in the optimum isometry of popliteus tendon, popliteofibular ligament, and lateral collateral ligament grafts in a knee with a reconstruction of the posterior cruciate ligament. Relative length changes (isometry measurements) were recorded between sutures fixed at femoral grid points and appropriate fibular or tibial graft tunnel sites; sites resulting in the least change in suture length as the knee was moved from 0 degrees to 90 degrees of flexion were identified as optimum isometric points. Bone blocks of Achilles tendon grafts were fixed with the midpoint of the tissue's leading edge adjacent to the optimum isometric point (optimum placement). Isometry measurements were repeated with a lateral collateral ligament graft placed in a fibular tunnel and with popliteus tendon and popliteofibular ligament grafts alternately placed in appropriate tibial and fibular tunnels. The graft isometry measurements were then repeated with the bone block centered over the femoral footprint of the lateral collateral ligament or popliteus tendon. For all reconstructions, there was no difference between the relative length changes of the suture placed at the optimum isometric point and the relative length changes of the graft with an optimally placed bone block. The mean location of the optimally placed bone-block center of the lateral collateral ligament graft was within 1.85 mm of the mean center of the footprint of the lateral collateral ligament; the mean graft isometry measurements with the optimally placed bone block were not significantly different from those with the bone block centered over the lateral collateral ligament footprint. The mean optimally placed bone-block center of the popliteus tendon and popliteofibular ligament reconstructions was 11 mm anterior and 2.7 mm proximal to the center of the popliteus tendon footprint. The mean relative length changes of the popliteus tendon and popliteofibular ligament grafts with the bone block optimally placed were <0.9 mm and <1.2 mm, respectively; the means with the popliteus tendon and popliteofibular ligament bone blocks centered over the popliteus tendon footprint were 3.7 mm and 5.0 mm, respectively. A popliteus tendon or popliteofibular ligament reconstruction with the bone block centered over the femoral footprint of the popliteus tendon was highly non-isometric. If the graft were fixed at 30 degrees of flexion, it would elongate approximately 4 mm when the knee was extended to 0 degrees and possibly stretch out.

How Well Do Anatomical Reconstructions of the Posterolateral Corner Restore Varus Stability to the Posterior Cruciate Ligament—Reconstructed Knee?

Background With grade 3 posterolateral injuries of the knee, reconstructions of the lateral collateral ligament, popliteus tendon, and popliteofibular ligament are commonly performed in conjunction with a posterior cruciate ligament reconstruction to restore knee stability. Hypothesis A lateral collateral ligament reconstruction, alone or with a popliteus tendon or popliteofibular ligament reconstruction, will produce normal varus rotation patterns and restore posterior cruciate ligament graft forces to normal levels in response to an applied varus moment. Study Design Controlled laboratory study. Methods Forces in the native posterior cruciate ligament were recorded for 15 intact knees during passive extension from 120° to 0° with an applied 5 N·m varus moment. The posterior cruciate ligament was removed and reconstructed with a single bundle inlay graft tensioned to restore intact knee laxity at 90°. Posterior cruciate ligament graft force, varus rotation, and tibial rotation were recorded before and after a grade 3 posterolateral corner injury. Testing was repeated with lateral collateral ligament, lateral collateral ligament plus popliteus tendon, and lateral collateral ligament plus popliteofibular ligament graft reconstructions; all grafts were tensioned to 30 N at 30° with the tibia locked in neutral rotation. Results All 3 posterolateral graft combinations rotated the tibia into slight valgus as the knee was taken through a passive range of motion. During the varus test, popliteus tendon and popliteofibular ligament reconstructions internally rotated the tibia from 1.5° (0° flexion) to approximately 12° (45° flexion). With an applied varus moment, mean varus rotations with a lateral collateral ligament graft were significantly less than those with the intact lateral collateral ligament beyond 0° flexion; mean decreases ranged from 0.8° (at 5° flexion) to 5.6° (at 120° flexion). Addition of a popliteus tendon or popliteofibular ligament graft further reduced varus rotation (compared with a lateral collateral ligament graft) beyond 25° of flexion; both grafts had equal effects. A lateral collateral ligament reconstruction alone restored posterior cruciate ligament graft forces to normal levels between 0° and 100° of flexion; lateral collateral ligament plus popliteus tendon and lateral collateral ligament plus popliteofibular ligament reconstructions reduced posterior cruciate ligament graft forces to below-normal levels—beyond 95° and 85° of flexion, respectively. Conclusions With a grade 3 posterolateral corner injury, popliteus tendon or popliteofibular ligament reconstructions are commonly performed to limit external tibial rotation; we found that they also limited varus rotation. With the graft tensioning protocols used in this study, all posterolateral graft combinations tested overconstrained varus rotation. Further studies with posterolateral reconstructions are required to better restore normal kinematics and provide more optimum load sharing between the PCL graft and posterolateral grafts. Clinical Relevance A lower level of posterolateral graft tension, perhaps applied at a different flexion angle, may be indicated to better restore normal varus stability. The clinical implications of overconstraining varus rotation are unknown.

A biomechanical analysis of two reconstructive approaches to the posterolateral corner of the knee

The objective of this study was to evaluate the effects of the biceps femoris tenodesis and popliteofibular ligament reconstruction on knee biomechanics. Ten human cadaveric knees were tested in the intact, posterolateral corner (PLC)-deficient, and PLC-reconstructed conditions using a robotic/universal force moment sensor testing system. The knees were subjected to: (1) a 134 N posterior tibial load, and (2) a 10 Nm external tibial torque applied to the tibia at full extension, 30 degrees and 90 degrees of flexion. External tibial rotation of the intact knee ranged from 18.3+/-4.6 degrees at full extension to 27.9+/-4.6 degrees at 30 degrees under the 10 Nm external tibial torque. These values increased after sectioning the PLC by 2.8 degrees -7.5 degrees at 30 degrees and 90 degrees respectively. After the popliteofibular ligament reconstruction, external tibial rotation values were not significantly different from those for the intact knee at any angle tested, while values following the biceps tenodesis were as much as 5.7 degrees greater than the intact knee. Under the 134 N posterior tibial load, there were minimal decreases in posterior tibial translation of up to 0.9 mm with the biceps tenodesis and up to 1.6 mm with the popliteofibular ligament reconstruction compared to the intact knee. The in situ forces in the biceps tenodesis were not significantly different than the intact PLC at full extension or 30 degrees, while the in situ forces in the popliteofibular graft were not significantly different at any flexion angle. Our data suggests that by restoring external tibial rotation the popliteofibular ligament reconstruction more closely reproduces the primary function of the PLC as compared to the biceps tenodesis.