Computer-assisted surgery for knee ligament reconstruction.

Background:Reports on outcome after posterior cruciate ligament (PCL) reconstruction often contain both isolated PCL and combined knee ligament injuries. This makes it difficult to conclude on the outcome after reconstruction of isolated PCL injuries.Purpose:To investigate the outcome after PCL reconstruction in patients with an isolated PCL injury and to compare this with the outcome of patients treated with reconstruction after isolated anterior cruciate ligament (ACL) injuries.Study Design:Cohort study; Level of evidence, 3.Methods:Seventy-one patients with an isolated PCL injury that was reconstructed surgically and who had registered in the Norwegian Knee Ligament Registry between 2004 and 2010 were included in this study. Patients with isolated ACL reconstructions (n = 9661) who had registered in the same period were included for comparison. Knee Injury and Osteoarthritis Outcome Score (KOOS) was used as the patient-reported outcome measure. Preoperative and 2-year postoperative KOOS scores were compared. Changes in KOOS score reported by the PCL patients were compared with changes reported by the ACL patients.Results:At the 2-year postoperative follow-up of the PCL-reconstructed patients, the patient-reported outcome was improved, measured by KOOS as follows: pain, 15.1 (95% CI, 8.5-21.8; P < .001); symptoms, 0.9 (95% CI, –6.6 to 8.3; P = .82); activities of daily living, 13.2 (95% CI, 6.6-13.9; P < .001); sports, 20.7 (95% CI, 11.8-29.4; P < .001); and quality of life, 26.6 (95% CI, 18.9-34.2; P < .001). According to the KOOS, the incremental improvements were similar for PCL and ACL patients. Time from injury to surgery was longer for the PCL patients compared with ACL patients (median, 21.5 vs 8.0 months; P < .001).Conclusion:Patients undergoing PCL reconstruction can expect the same improvements in KOOS score as patients undergoing ACL reconstruction. However, PCL patients start out with an inferior score on average and consequently end up at a lower score compared with ACL patients for all KOOS subscales.

Background: Several new procedures for medial collateral ligament (MCL) reconstruction using a hamstring tendon graft have been reported in the 2000s. However, the midterm and long-term clinical outcomes of these procedures have not been reported. Hypothesis: Postoperative medial stability of the knee that underwent our MCL reconstruction may not be significantly different from that of the noninjured knee. Study Design: Case series; Level of evidence, 4. Methods: A total of 37 patients who sustained multiligamentous knee injuries underwent combined MCL and cruciate ligament reconstruction at our institution between 1994 and 2007. Thirty of the 37 patients were clinically evaluated at least 2 years after surgery. Sixteen had combined MCL and anterior cruciate ligament (ACL) reconstruction, 5 had combined MCL and posterior cruciate ligament (PCL) reconstruction, and 9 had combined MCL, ACL, and PCL reconstruction. The International Knee Documentation Committee (IKDC) evaluation form and Lysholm score were used to evaluate postoperative knee function. Anteroposterior knee laxity was examined with a KT-2000 arthrometer. To assess objective medial instability, we performed a stress radiograph examination under valgus stress with the knee at 20° of flexion. Results: At the final follow-up, 1 patient showed a loss of knee extension of more than 3°. Five patients revealed a loss of knee flexion of 6° to 15° and 2 patients of 16° to 25°. Lysholm scores averaged 94.8 points. In the IKDC evaluation, 9 patients were graded as A, 17 were graded as B, 3 were graded as C, and 1 was graded as D. In the stress radiograph examination, the mean medial joint opening was 8.5 ± 1.6 mm in the reconstructed knee and 8.0 ± 1.2 mm in the healthy opposite knee. There was no significant difference in the medial joint opening between reconstructed and intact knees. Conclusion: Medial collateral ligament reconstruction for chronic combined knee instabilities can be safely performed using hamstring tendon autografts, and the clinical outcome with a minimum 2-year follow-up was favorable with satisfactory stability.

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Background: Outcomes after posterior cruciate ligament (PCL) reconstruction (PCLR) have been reported to be inferior to those of anterior cruciate ligament reconstruction. Furthermore, combined ligament injuries have been reported to have inferior outcomes compared with isolated PCLR. Purpose/Hypothesis: The purpose of this study was to report on PCLR outcomes and failure rates and compare these outcomes between isolated PCLR and multiligament knee surgery involving the PCL. The hypothesis was that combined PCL injury reconstruction would have higher rates of subjective failure and revision relative to isolated PCLR. Study Design: Cohort study; Level of evidence, 3. Methods: Patients with primary PCLR with or without concomitant ligament injuries registered in the Norwegian Knee Ligament Registry between 2004 and 2021 were included. Knee injury and Osteoarthritis Outcome Score (KOOS) totals were collected preoperatively and at 2 years and 5 years postoperatively. The primary outcome measure was failure, defined as either a revision surgery or a KOOS Quality of Life (QoL) subscale score <44. Results: The sample included 631 primary PCLR procedures, with 185 (29%) isolated PCLR procedures and 446 (71%) combined reconstructions, with a median follow-up time of 7.3 and 7.9 years, respectively. The majority of patients had poor preoperative knee function as defined by a KOOS QoL score <44 (90.1% isolated PCLR, 85.7% combined PCL injuries; P = .24). Subjective outcomes improved significantly at 2- and 5-year follow-up compared with preoperative assessments in both groups (P < .001); however, at 2 years, 49.5% and 46.5% had subjective failure (KOOS QoL <44) for isolated PCLR and combined PCLR, respectively (P = .61). At 5 years, the subjective failure rates of isolated and combined PCLR were 46.7% and 34.2%, respectively (P = .04). No significant difference was found in revision rates between the groups at 5 years (1.9% and 4.6%, respectively; P = .07). Conclusion: Patients who underwent PCLR had improved KOOS QoL scores relative to their preoperative state. However, the subjective failure rate was high for both isolated and multiligament PCLR. Within the first 2 years after surgery, patients who undergo isolated PCLR can be expected to have similar failure rates to patients who undergo combined ligament reconstructions.

Combined Lateral Extra-Articular Tenodesis or Combined Anterolateral Ligament Reconstruction and Anterior Cruciate Ligament Reconstruction Improves Outcomes Compared to Isolated Reconstruction for Anterior Cruciate Ligament Tear: A Network Meta-analysis of Randomized Controlled Trials

Arthroscopic All-Inside Posterior Cruciate Ligament Reconstruction: Overcoming the “Killer Turn”

Objective: To investigate the effect of soft-tissue referenced tibial tunnel positioning based on the distal fold of the posterior capsule and the posterior compartment on the"killer turn"effect in posterior cruciate ligament (PCL) reconstruction. Methods: A retrospective analysis was conducted on the clinical data of 40 patients with PCL injury who underwent reconstruction surgery in the Department of Joint Surgery, the Third Hospital of Hebei Medical University, from July 2023 to October 2024. All patients underwent PCL reconstruction by the same surgical team. The distal fold of the posterior capsule and the posterior septum were set as reference landmarks at the tibial side. MRI was used to measure the soft-tissue and bony"killer turn"angles of 20 patients immediately postoperatively and at 6 months after the surgery, to assess the impact of soft-tissue referenced positioning and remnant-preserving PCL reconstruction on the"killer turn"effect and its dynamic changes. Graft diameters of these 20 patients were measured on MRI immediately postoperatively and at 6 months and were compared. The graft and remnant morphology and the status of the posterior capsule were evaluated too. The knee stability and functional scores [Lysholm score, Tegner activity score, International Knee Documentation Committee (IKDC) score] were assessed in the other 20 patients with 1 year of follow-up. A 30-year-old male volunteer underwent CT scanning and reconstruction to create a three-dimensional finite element model of the knee joint. Two models were established based on whether the PCL remnant was preserved or not: a soft-tissue referenced non-remnant-preserving PCL reconstruction model and a remnant-preserving PCL reconstruction model. A posterior drawer test was simulated to compare the stress conditions of the grafts in the two models. Results: A total of 40 eligible patients [including 27 males and 13 females, aged (37.2±14.9) years] were included in this study. The imaging data of these patients were included. Immediately postoperatively, the soft-tissue"killer turn"angle was 104.70°±7.95°, and the bony"killer turn"angle was 91.39°±10.21° (P<0.001). At 6 months postoperatively, the soft-tissue"killer turn"angle was 108.13°±12.01°, was comparable with the immediate postoperative value (P=0.107); and the graft diameter did not change significantly at 6 months postoperatively when compared with the immediate postoperative period [[(7.58±0.57) mm] vs (7.65±0.56) mm, P=0.167]. Ultrasound at 6 months postoperatively showed intact graft morphology and the distal fold structure of the posterior capsule. At 1 year postoperatively, the Lysholm score, Tegner activity score and IKDC score all improved significantly when compared to the preoperative values (all P<0.05). In the finite element analysis, the remnant-preserving model exhibited lower graft tension, interaction force with the tibial plateau, and frictional force compared to the non-remnant-preserving model. Conclusion: The soft-tissue referenced tibial tunnel positioning based on the distal fold of the posterior capsule and the posterior compartment for remnant-preserving PCL reconstruction can effectively reduce the"killer turn"effect, minimize graft-bone friction, and prevent graft wear and thinning.

Double-bundle posterior cruciate ligament reconstruction: No differences between two types of autografts in isolated or combined lesions

Background: There has been no previous study regarding graft selection in anterior cruciate ligament (ACL) reconstruction for smoking patients. Purpose: To compare the clinical outcomes of ACL reconstruction between smokers and nonsmokers and to find an optimal graft in ACL reconstruction with regard to clinical outcomes for smoking patients. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 487 patients who underwent unilateral ACL reconstruction were retrospectively reviewed. Included patients were divided into 2 groups according to their history of smoking. Group 1 was composed of patients who had never smoked (n = 322), and group 2 consisted of patients who had reported smoking before ACL reconstruction and during rehabilitation (n = 165). Additionally, each group was divided into 4 subgroups according to the selected graft type (bone–patellar tendon–bone autograft, hamstring [semitendinosus-gracilis] tendon autograft, quadriceps tendon–bone autograft, or Achilles tendon–bone allograft). Patients were assessed for knee instability with the Lachman and pivot-shift tests as well as anterior translation measured by the KT-2000 arthrometer. Functional outcomes were evaluated with the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective score, and IKDC objective grade. Results: The minimum follow-up period was 24 months. At the final follow-up evaluation, there were significant mean between-group differences regarding the side-to-side difference in anterior translation (group 1, 2.15 ± 1.11 mm; group 2, 2.88 ± 1.38 mm; P < .001), Lysholm knee score (group 1, 90.25 ± 6.18; group 2, 84.79 ± 6.67; P < .001), IKDC subjective score (group 1, 89.16 ± 5.01; group 2, 83.60 ± 7.48; P < .001), and IKDC objective grade (group 1, grade A = 151, B = 130, C = 36, D = 5 patients; group 2, grade A = 48, B = 71, C = 37, D = 9 patients; P < .001). With regard to differences in outcomes between the selected grafts within each group, the Achilles tendon–bone allograft showed the worst outcomes, with statistically significant mean differences for smoking patients in the side-to-side difference in anterior translation (3.59 ± 1.26 mm), Lysholm knee score (81.05 ± 2.82), and IKDC subjective score (79.73 ± 4.29). Conclusion: Unsatisfactory outcomes with regard to stability and functional scores were shown in the smoking group compared with the nonsmoking group. In smokers, the patients receiving an Achilles tendon–bone allograft had poorer outcomes than those with autografts. The bone–patellar tendon–bone autograft is recommendable for ACL reconstruction in a smoking patient.

The purpose of this paper is to review the literature about the contribution of navigation in anterior cruciate ligament (ACL) reconstruction. The evolution of computer-assisted surgery (CAS) for ACL reconstruction has undergone several steps. These steps were divided into 4 subsequent developments: (1) positioning of ACL graft placement; (2) laxity measurement of ACL reconstruction (quality control); (3) kinematic evaluation during ACL reconstruction (navigated pivot shift); (4) case-specific individual ACL reconstruction with adjustments and additional reconstruction options. CAS has shown to improve femoral tunnel positioning, even if clinical outcomes do not improve results of manual techniques. CAS technology has helped researchers better understand the effects of different ACL reconstruction techniques and bundles replacements on joint laxity and to describe tunnel positioning in relation to native ACL insertion. CAS in ACL surgery can improve results at time zero and can improve knowledge in this field.

Objective To introduce a new posterior-anterior approach used to establish tibial tunnel for all-inside posterior cruciate ligament (PCL) reconstruction and evaluate its short-term therapeutic effects. Methods We retrospectively analysed the 15 patients (15 knees) with PCL injury who had been treated at Department of Orthopaedics, Zhejiang Provincial People's Hospital from January 2017 to January 2018. They were 9 men and 6 women, with a mean age of 46.3 years (from 23 to 60 years). Of them, 8 left and 7 right sides were injured. The intervals from injury to surgery averaged 33.6 days (from 4 to 120 days). Their injury was complicated with medial meniscus tear in 3 cases, lateral meniscus tear in one case, lesion of medial col-lateral ligament in 2 cases and lesion of lateral medial collateral ligament in one case. After preoperative physical examination and MRI confirmed complete PLC tear in all of them, they were treated by arthroscopic all-inside PCL reconstruction in which a new posterior-anterior approach was used to establish the tibial tunnel. Lysholm scoring and International Knee Documentation Committee (IKDC) scoring were used preoperatively and postop-eratively to evaluate the knee functions. Results Their follow-ups averaged 8.3 months (from 6 to 12 months). Operation time averaged 55 minutes (from 45 to 70 minutes). All the patients got rid of the knee instability after surgery. All their posterior drawer tests and sag signs turned to be negative. At the final fol-low-up, their range of motion of the knee ranged from 110° to 130° (average, 118°); their average IKDC score was 88.1±3.3 (from 82 to 93), significantly higher than the preoperative value (52.3±2.1) (P<0.05); their average Lysholm score was 90.6±3.1 (from 84 to 96), significantly higher than the preoperative value (43.1±2.3) (P<0.05). Conclusions This new method can avoid neurovascular damage and overcome the killer turn because it provides adequate exposure of the tibial PCL footprint and accurate placement of the tibial tunnel. It is also very convenient because the new posterior-anterior approach can be used to establish the tibial tunnel in all-inside PCL reconstruction without special tools like tibial PCL guide and retrograde drill. Its short-term clinical results have proved to be satisfactory. Key words: Posterior cruciate ligament; Arthroscopy; Wounds and injuries; Tibial tunnel

To explore the effectiveness of one-stage posterior medial corner (PMC) repair or reconstruction combined with anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstruction in treating KD-ⅢM dislocation. The clinical data of 15 patients with knee KD-ⅢM dislocation who met the selection criteria between January 2016 and July 2019 were retrospectively analyzed. There were 9 males and 6 females, aged 22-61 years (mean, 40.3 years). Injuries were caused by violence of flexion, valgus, and external rotation, including 10 cases of traffic accident injuries, 3 cases of crush injuries, 1 case of winch injury, and 1 case of explosion injury. The time from injury to operation ranged from 3 days to 6 months, with an average of 18.5 days. PMC repair combined with PCL+ACL reconstruction was performed in 10 cases in acute stage (within 3 weeks after injury), including 3 cases of irreducible dislocation. PMC+PCL+ACL reconstruction was performed in 5 cases with chronic dislocation. Before operation and at last follow-up, the knee joint function was evaluated by Lysholm score and International Knee Documentation Committee (IKDC) 2000 score. KT-3000 was used to evaluate the forward stability of the knee (calculated the difference of tibial anterior displacement of both knees), the X-ray films of the stress position of the knee joint was used to evaluate the valgus of the knee (calculated the difference of medial joint space width of both knees) and the backward stability (calculated the difference of tibial posterior displacement of both knees), and the internal and external rotation stability was evaluated by knee flexion 30° tibial external rotation and knee flexion 90° tibial internal rotation tests (calculated the difference of tibial internal rotation and the difference of tibial external rotation of both knees). The operation time was 120-240 minutes, with an average of 186.5 minutes. Patients were followed up 24-48 months, with an average of 27.4 months. There was no complication such as infection, deep vein thrombosis, vascular injury, or heterotopic ossification. At last follow-up, the Lysholm score, IKDC2000 score, the difference of tibial anterior displacement of both knees, the difference of medial joint space width of both knees, the difference of tibial posterior displacement of both knees, the difference of tibial internal rotation and the difference of tibial external rotation of both knees significantly improved when compared with preoperative ones ( P<0.05). According to the IKDC2000 valgus stability grading standard, there were 3 cases of grade C and 12 cases of grade D before operation, and 10 cases of grade A and 5 cases of grade B at last follow-up, which was significantly improved when compared with that before operation ( Z=-4.930, P=0.000). At last follow-up, the pivot shift tests of 15 patients were negative. The anterior and posterior drawer tests of 10 patients were negative, 5 patients had mild instability, both the anterior and posterior drawer tests were positive. KD-ⅢM dislocation of the knee joint can lead to the posterior medial and anterior instability. Acute dislocation combined with "dimple sign" requires surgical reduction as soon as possible to repair PMC and reconstruct PCL and ACL. In chronic patients, PMC is difficult to repair, it is recommended to reconstruct PMC, PCL, and ACL at one stage to improve knee joint stability. The early and middle effectiveness are satisfactory.

Arthroscopic Reconstruction of the Posterior Cruciate Ligament With Use of a Quadruple Hamstring Tendon Graft With 3- to 5-Year Follow-up

To compare the long term outcomes of transtibial nonanatomic single-bundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. Between January 2008 and September 2010, we retrospectively evaluated 377 patients who underwent primary ACL reconstruction and who were available at 8 years of follow-up. Patients who received transtibial nonanatomic SB ACL reconstruction ( n = 263) were assigned to group SB and DB ACL reconstruction ( n = 114) to group DB. The patients were assessed with the International Knee Documentation Committee (IKDC), the Lysholm scores, Tegner activity score, knee joint stability tests, and patellofemoral osteoarthritis (OA) findings using the Kellgren-Lawrence (K-L) classification. Contralateral ACL (CACL) injury was also evaluated. Thirteen patients underwent revision ACL surgery during the follow-up. Ultimately, 256 patients in group SB and 108 patients in group DB were available at the 8-year follow-up. At final follow-up, the IKDC subjective score ( p = 0.04) and Lysholm score ( p = 0.02) showed significantly superior results in group DB compared to group SB. However, there was no significant difference of Tegner activity score ( p = 0.30), range of motion ( p = 0.81), and knee joint stability tests. There was significant progression of patellofemoral OA between preoperative and final follow-up in ipsilateral knee of both groups but not significant progression in contralateral knee. However, there was no significant difference between the two groups at the follow-up. There were 2.7% ipsilateral ACL graft failure in group SB, compared with 5.2% in group DB ( p = 0.12) and 6.4% CACL tear in group SB, compared with 5.2% in group DB ( p = 0.65). The mean survivorship of ACL graft was 9.47 ± 0.05 years (95% confidence interval (CI), 9.36-9.58) in group SB and 9.87 ± 0.16 years (95% CI, 9.54-10.20) in group DB, and there was no significant difference ( p = 0.25). DB ACL reconstruction resulted in significantly better clinical IKDC subjective scores and Lysholm scores. However, most of the differences in clinical scores were small, and the clinical relevance of this difference is unknown. In addition, there was no significant difference in Tegner activity score, knee joint stability tests, patellofemoral OA, and survivor rate of the ACL graft and CACL after reconstruction after a minimum of 8-year follow-up. Level of Evidence: Cohort study; level of evidence, 3.

Background Failure to address both components of a combined posterior cruciate ligament and posterolateral corner injury has been implicated as a reason for abnormal biomechanics and inferior clinical results. Hypothesis Combined double-bundle posterior cruciate ligament and posterolateral corner reconstruction restores the kinematics and in situ forces of the intact knee ligaments. Study Design Controlled laboratory study Methods Ten fresh-frozen human cadaveric knees were tested using a robotic testing system through sequential cutting and reconstructing of the posterior cruciate ligament and posterolateral corner. The knees were subjected to a 134-N posterior tibial load and a 5-N.m external tibial torque at multiple flexion angles. The double-bundle posterior cruciate ligament reconstruction was performed using Achilles and semitendinosus tendons. The posterolateral corner reconstruction consisted of reattaching the popliteus tendon to its femoral origin and reconstructing the popliteofibular ligament with a gracilis tendon. Results Under the posterior load, the combined reconstruction reduced posterior translation to within 1.2 - 1.5 mm of the intact knee. The in situ forces in the posterior cruciate ligament grafts were significantly less than those in the native posterior cruciate ligament at all angles except full extension. Conversely, the forces in the posterolateral corner grafts were significantly higher than those in the native structures at all angles. Under the external torque with the combined reconstruction, external rotation as well as in situ forces in the posterior cruciate ligament and posterolateral corner grafts were not different from the intact knee. Conclusions A combined posterior cruciate ligament and posterolateral corner reconstruction can restore intact knee kinematics at time zero. In situ forces in the intact posterior cruciate ligament and posterolateral corner were not reproduced by the reconstruction; however, the posterolateral corner reconstruction reduced the loads experienced by the posterior cruciate ligament grafts. Clinical Relevance By addressing both structures of this combined injury, this technique restores native kinematics under the applied loads at fixed flexion angles and demonstrates load sharing among the grafts creating a potentially protective effect against early failure of the posterior cruciate ligament grafts but with increased force in the posterolateral corner construct.