Multiple Ligament Reconstructions of the Knee and Posterolateral Corner

Autologous Single Semitendinosus Anatomical Posterolateral Corner Reconstruction With Adjustable-Loop Cortical Suspension Devices

We present our surgical technique for the reconstruction of the posterolateral corner of the knee. It is a tibia- and fibular-based reconstruction technique. Most of these procedures require the use of 2 tendons (autograft or allograft). In our technique, a single semitendinosus tendon is required, making the procedure more suitable if the surgeon prefers the use of autograft or when there is no access to a tissue bank. This is even more important in the setting of multiligament knee injuries. The most defining feature of this modification is the possibility of achieving the desired graft tension in a progressive and independent way, due to the use of 3 adjustable-loop cortical suspension devices.

The diagnostic accuracy of MRI for evaluating the posterolateral corner in acute knee dislocation

OBJECTIVE

To investigate the diagnostic performance of preoperative MRI in evaluating posterolateral corner (PLC) structures after acute knee dislocation (KD) and determine the correlation of MRI with operative findings for grading structure integrity.

METHODS

Acute knee (femorotibial) dislocations between 2005 and 2020 with preoperative MRI and surgical posterolateral corner repair were identified from a single academic institution. From MRI, integrity was evaluated for PLC structures: lateral collateral ligament (LCL), popliteus tendon (PT), biceps femoris tendon (BFT), and ligamento-capsular complex (LCC). Frequency of injury to each structure and number of PLC structures torn in each case were tabulated. Diagnostic performance of MRI was determined using surgery as the reference standard. Correlation between MRI and surgery for each PLC structure was determined using kappa.

RESULTS

Thirty-nine KD cases (19 right) in 39 patients (28 male) were included, with mean age of 33 years. Mechanism of injury was as follows: high energy 52%, low energy 38%, ultra-low energy 10%. LCL was most frequently torn, in 95% (37/39) of cases. Most commonly, three of four PLC structures were torn in 54% (21/39) of cases. Diagnostic accuracy of MRI was high for LCL 95%, BFT 87%, PT 82%, and LCC 92%. Correlation between MRI and surgical findings was variable: substantial for BFT, moderate for LCL and PT, and fair for LCC.

CONCLUSION

MRI has high accuracy for detecting tears of posterolateral corner stabilizers in the setting of acute KD. However, for grading structure integrity, the correlation of MRI with surgical findings is variable, ranging from fair to substantial.

KEY POINTS

• In acute knee dislocation, MRI has high diagnostic accuracy for detecting tears of posterolateral corner (PLC) structures. • Preoperative MRI should be considered by orthopedic surgeons when there is clinical concern for posterolateral corner instability following acute knee dislocation. • Although MRI is valuable in the preoperative investigation of knee dislocation, clinical assessment and intraoperative exploration may still be required for definitive diagnosis.

[Short-term effectiveness of one-stage anterior and posterior cruciate ligaments and posterolateral complex reconstruction combined with medial collateral ligament repair for KD- knee dislocation]

OBJECTIVE

To investigate the short-term effectiveness of one-stage anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and posterolateral complex (PLC) reconstruction combined with medial collateral ligament repair for KD-Ⅳ knee dislocation.

METHODS

Between January 2018 and June 2020, 9 patients with KD-Ⅳ knee dislocation were treated. Of 9 cases, 7 were male and 2 were female with an average age of 32.3 years (range, 23-43 years). The knee dislocation was caused by falling from height in 6 cases and traffic accident in 3 cases. The injury located at left knee in 2 cases and right knee in 7 cases. The time from injury to operation was 14-24 days, with an average of 19 days. The preoperative International Knee Joint Documentation Committee (IKDC) score was 45.6±4.2, Lysholm score was 42.4±7.0, and the knee joint active flexion range of motion was (75.2±12.3)°. The posterior drawer test, pivot-shift test, Dial test, and 0° valgus stress test were all positive. Under arthroscopy, PCL was reconstructed with the autologous tendons, ACL with allogeneic Achilles tendon, PLC with the allogeneic anterior tibial tendon by Larson enhanced reconstruction method, and MCL was repaired with anchor or simple suture.

RESULTS

The operation time was 2-3 hours (mean, 2.5 hours). All incisions healed by first intention after operation. All patients were followed up12-25 months (mean, 16.1 months). After operation, 2 cases developed knee flexion disorder and pain, and 1 case had knee joint stiffness. At last follow-up, the IKDC score was 76.9±7.4, the Lysholm score was 81.6±6.4, and the knee active flexion range of motion was (122.9±7.2)°, all of which significantly improved when compared with preoperative ones ( P<0.05). During follow-up, there was no failure of the grafts. At last follow-up, there were significant differences in the posterior drawer test, pivot-shift test, Dial test, and 0° valgus stress test between pre- and post-operation ( P<0.05). The imaging review showed that the positions of the bone tunnels were satisfactory, the reconstructed ACL, PCL, and PLC structures were continuous, and MCL insertions were restored.

CONCLUSION

One-stage ACL, PCL, and PLC reconstruction combined with MCL repair to treat KD-Ⅳ knee dislocation can effectively restore knee joint stability, improve joint laxity, and improve joint movement.