Anterior Cruciate Ligament Repair Leads to Improved Patient-Reported Outcomes Compared to Anterior Cruciate Ligament Reconstruction.

Introduction Anterior cruciate ligament (ACL) tears occur frequently in young athletes, and ligament repair and reconstruction are surgical treatments. Although there are suggested benefits for both approaches, there is a lack of direct comparisons between ACL repair and reconstruction.This study aims to compare the mid-term functional outcomes and quality of life measures between patients that have undergone ACL repair versus reconstruction. Methods A retrospective review was conducted for demographic and operative report data of patients who underwent an ACL repair or reconstruction between 2012 and 2018. Patients were contacted over the phone and underwent a Patient-Reported Outcomes Measurement Information System (PROMIS) survey evaluating pain interference, mobility, and function. Patients were excluded from the study if there was an incomplete operative note, missing contact information, or failure to answer phone calls. Results A total of 74 eligible patients were included, with n = 54 in the ACL reconstruction group (73.0%) and n = 20 in the ACL repair group (27.0%). Reconstruction patients had a PROMIS (median (IQR)) physical function score of 22.50 (16.00-59.00), as compared to repair patients' physical function score of 60.00 (21.50-60.00). There was a significant difference favoring repair (p = 0.040). In addition, ACL reconstruction patients had a significantly higher rate of additional procedures, with 63.0% of reconstruction patients receiving an additional operation as compared to 30.0% of repair patients (p = 0.017). The surgery type did not show a significant effect on physical function scores, while additional procedures remained significant in the linear regression analysis. Conclusion Although ACL repair is associated with improved physical function scores as compared to reconstruction in the univariate analysis, surgery type did not show significance when controlling for other variables. Further studies are necessary to compare patients with similar injuries to account for differences in additional procedures, but the results remain promising in assisting with patient-driven treatment decisions.

Rehabilitation Following ACL Repair with Internal Brace Ligament Augmentation in Female Gymnast: A Resident's Case Report.

Introduction: Anterior Cruciate Ligament (ACL) injuries continue to be a major source of morbidity in gymnastics. The gold standard is to perform an ACL Reconstruction (ACLR). However, injuries to the proximal femoral attachment of the ACL have demonstrated an ability to regenerate. An alternative surgical intervention to the ACLR in this ACL tear subgroup is an ACL repair. The purpose of this case report is to provide a rehabilitation progression for a female gymnast after an ACL repair with Internal Brace Ligament Augmentation (IBLA). Case Description: The subject was a 16-year-old female who presented with a Sherman Type 1 proximal avulsion of her ACL. She underwent an ACL repair with IBLA. Physical therapy interventions followed a sequential and multi-phased approach based on time for tissue physiologic healing and individual progression. Patient reported outcomes including the International Knee Documentation Committee (IKDC), the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) and the Optimal Screening for Prediction of Referral and Outcome Yellow Flag (OSPRO-YF) were assessed in conjunction with isokinetic strength and hop performance testing to determine return to sport readiness. Outcomes: The subject completed 42 sessions over the course of 26 weeks in addition to a home exercise program. At return to sport, clinically meaningful improvement was observed in patient reported outcomes including the IKDC, ACL-RSI, and OSPRO-YF. Additionally, strength and hop performance surpassed established thresholds of clinical significance. The subject returned to sport at six months post-operatively. Conclusion: The subject in this case report returned to full participation in gymnastics six months after an ACL repair with internal bracing following a sequential and multi-phased rehabilitation. The primary ACL repair with IBLA appeared beneficial to this patient and could benefit from additional study in other athletes and athletic populations. Level of Evidence: Level 5.

Anterior Cruciate Ligament Repair-Here to Stay or History Repeating Itself?

Anterior cruciate ligament (ACL) injuries continue to be a prevalent concern among athletes and individuals with an active lifestyle. Traditionally, the standard of care for ACL tears has involved surgical reconstruction using autograft or allograft. This article aims to provide an overview of the evolving landscape of primary ACL repair, examining the current evidence, surgical techniques, patient selection criteria, outcomes, and potential future directions in this field.

Conservative vs Surgical Treatment of Anterior Cruciate Ligament Rupture: A Systematic Review.

Anterior cruciate ligament (ACL) injury is very common, especially in young athletic individuals who injure themselves during sports involving pivoting actions. Management options include conservative management, which involves progressive physical therapy, educating the patient on how to prevent instability, and the use of a hinged knee brace. Surgical management involves reconstruction of the torn ligament using an autograft or an allograft and ACL repair where the torn ligament is affixed back to the tibia or femur. The choice of management depends on the severity of the injury, other injuries in associated structures, the level of fitness, and the athletic goals of the patient. Many studies exist on the management choice of ACL injury, but no clear consensus prevails. This study will examine the effectiveness of conservative versus surgical management. A literature review will be performed to identify appropriate papers which compare and evaluate the two approaches. A literature search for randomized controlled trials (RCTs) and cohort studies comparing the conservative to surgical management of ACL injury was conducted on PubMed, Scopus, and Web of Science. Patient eligibility criteria included individuals older than 15 with an isolated, recent ACL injury diagnosis via an appropriate clinical test, MRI, or arthroscopy. Studies were eligible if they were using appropriate surgical or conservative methods, as mentioned previously, and measuring results via appropriate scores, tools, and methods that will be presented below. The follow-up timeline would be from presentation time until at least two years. Five papers were found to be eligible. Overall, these papers included 462 patients. Two studies measuring overall knee symptoms, function, and sports activities using the International Knee Documentation Committee Subjective Knee Form (IKDC) score found that the operated group had a significantly higher score. The other two studies measured overall knee function and health using the Tegner & Lysholm and Knee Injury and Osteoarthritis Outcome Score (KOOS) scores. In both papers, no significant difference was found between the two groups. Regarding Tegner's activity score, only one paper had significant findings. A significantly longer period to return to sports activities was observed in the operative group. Stability was significantly higher in all papers in the operated group. Osteoarthritis was measured using different tools in each paper. Only one paper found a significantly higher risk in the operated group. Only one paper indicated significantly more complications in the operated group regarding side effects. Overall, very few differences were observed between the two treatment groups. The most significant differences observed were the higher stability and the longer recovery period in patients undergoing surgery. Large RCTs following patients for enough time are needed to prove if surgical treatment offers significant benefits over conservative treatment.

Influence of a Concomitant Medial Meniscus Injury on Knee Joint Function and Osteoarthritis Presence after Anterior Cruciate Ligament Reconstruction.

(1) Background: The aim of this study was to investigate how a medial meniscus injury accompanying an anterior cruciate ligament rupture affects the clinical outcome 10 years after ACL reconstruction. (2) Methods: A total of 37 patients who received anterior cruciate ligament reconstruction (ACLR) were included in this retrospective study. Two groups were analyzed at a single follow-up of 10 years: (i) "isolated (ACLR)" (n = 20) and (ii) "ACLR with medial meniscal injury" (n = 17). The following clinical scores were recorded: International Knee Documentation Committee (IKDC), the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm Score and Tegner Activity Score. To determine the degree of osteoarthritis the Kellgren-Lawrence score was used. (3) Results: The "isolated ACLR" study group scored significantly higher (p < 0.05) on the IKDC subjective questionnaire (mean: 88.4) than the "ACLR with medial meniscus injury" group (mean: 81). The KOOS category "activities of daily living" showed significantly better results in the isolated ACLR group (p < 0.05). The "ACLR with medial meniscus injury" group had significantly higher degree of osteoarthritis (p < 0.05). No significant differences were found in all the other clinical scores. (4) Conclusions: The results of this study further indicate that patients with a concomitant medial meniscus injury have slightly more discomfort in everyday life and increased risk of developing osteoarthritis 10 years after surgery.

Stabilization and Gap Formation of Adjustable Versus Fixed Primary ACL Repair With Internal Brace: An in Vitro Full-Construct Biomechanical Cadaveric Study.

Background: A knotless, tensionable primary anterior cruciate ligament (ACL) repair system preloaded with an internal brace has been released. Currently, there is no biomechanical data on the stabilization and gap formation behavior of the adjustable system when compared with fixed repairs in human ACL tissue. Hypothesis: That knotless adjustable suture repair with an internal brace would provide overall higher construct stability and greater load share on the ACL with less gap formation compared with fixed repair. Study Design: Controlled laboratory study. Methods: Human cadaveric knees were utilized for internal braced ACL repair constructs (each group n = 16). Two fixed groups consisting of a single-cinch loop (SCL), cortical button (SCL group), and knotless suture-anchor (anchor group) were compared with an SCL-adjustable loop device (SCL-ALD) group. Testing was performed at 4 different peak loads (50, 150, 250, 350 N) over 4000 cycles at 0.75 Hz including suture repair preconditioning (10 cycles at 0.5 Hz) for SCL-ALD. Specimens were ultimately pulled to failure with a cut internal brace. The final loading situation of the construct and ACL repair with gap formation and ultimate strength were evaluated. Results: Peak elongation at various peak loads showed a significantly higher (P < .001) stabilization of SCL-ALD when compared with both fixed groups. There was a significantly higher (P < .001) load share of SCL-ALD, especially at lower loads (48% of 50 N), and the gap formation remained restricted up to 250 N. With only a little load share on the fixed constructs (<6%) at lower loads (50, 150 N), gap formation in these groups started at a load of 150 N, leading to significantly higher gaps (P < .001). The ultimate failure load for SCL-ALD and anchor groups was significantly increased (P < .001) as compared with SCL. The stiffness of SCL-ALD (62.9 ± 10.6 N/mm) was significantly increased (P < .001). Conclusion: Internal braced knotless adjustable fixation for ACL repair with preconditioning of the suture repaired ligament increased the overall stabilization with higher load share on the ACL and restricted gap formation (<0.5 mm up to 350 N) compared with fixed suture repair. All internal braced repairs restored stability according to native ACL function. Clinical Relevance: Adjustable ACL repair improved the mechanical characteristics and reduced gap formation, but the overall clinical significance on healing remains unclear.

Favorable Patient-Reported, Clinical, and Functional Outcomes 2 Years After ACL Repair and InternalBrace Augmentation Compared With ACL Reconstruction and Healthy Controls.

BACKGROUND: Recently, interest in anterior cruciate ligament (ACL) preservation and repair after proximal ACL tears has been resurrected. Although good clinical outcomes have been reported in the literature with adequate patient selection, to date detailed scientific evidence for the functional benefit of primary ACL repair with ligament augmentation is scarce. PURPOSE: To compare patient-reported, clinical, and functional outcomes in patients 2 years after ACL repair and InternalBrace augmentation (ACL-IB) with age- and sex-matched patients 2 years after ACL reconstruction (ACL-R) and with matched healthy controls. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: In total, 29 patients 2 years after ACL-IB, 27 sex- and age- matched patients 2 years after ACL-R (hamstring autografts), and 29 matched healthy controls were included. Patient-reported outcomes were assessed using the International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, EQ-5D-5L, Tegner Activity Scale, and Anterior Cruciate Ligament Return to Sports after Injury scale. Surgery time was recorded. For clinical outcomes, range of motion and thigh and shank circumference were measured, and passive anterior translation was determined using the Rolimeter. Isokinetic muscle strength was measured using a Biodex dynamometer. The limb symmetry index (operated/contralateral or nondominant/dominant × 100), side-to-side differences (operated - contralateral, nondominant - dominant), and hamstring-quadriceps ratios were calculated for functional parameters. Failure and reoperation rates were not compared. RESULTS: Two years after surgery, patients treated with ACL-IB showed good to excellent patient-reported outcomes comparable with those of patients after ACL-R. Surgery time, including concomitant surgeries, was significantly shorter in the ACL-IB group (mean, 81 minutes) compared with the ACL-R group (mean, 97 minutes) (P = .024). Isokinetic muscle strength was comparable between patient groups without significant differences in extensor and flexor strength or in hamstring-quadriceps ratios. CONCLUSION: These results suggest that ACL-IB achieves comparable patient-reported, clinical, and functional outcomes with ACL-R at 2 years postoperatively and, after careful patient selection, should be considered as a valuable early treatment alternative for proximal ACL tears. REGISTRATION: NCT04429165 (ClinicalTrials.gov identifier).

Functional leg performance 2 years after ACL surgery: a comparison between InternalBrace™-augmented repair versus reconstruction versus healthy controls.

BACKGROUND: While clinical and patient-reported outcomes have been investigated in patients after InternalBrace™-augmented anterior cruciate ligament repair (ACL-IB), less is known regarding restoration of functional performance. We aimed to determine differences in functional performance within and between patients 2 years after ACL-IB, patients 2 years after ACL reconstruction (ACL-R), and healthy controls. MATERIALS AND METHODS: A total of 29 ACL-IB, 27 ACL-R (hamstring autograft), and 29 controls performed single-leg hop (maximum forward distance hop, SLH; side hop > 40 cm in 30 s, SH), proprioception (knee joint position sense at 30° and 60° flexion), and dynamic postural balance (Y Balance) tests. Differences were calculated within groups (side-to-side difference) and between the involved leg of patients and the non-dominant leg of controls, and were evaluated to predefined statistical (P < 0.05), clinically relevant, and methodological (smallest detectable change) thresholds. The number of exceeded thresholds represented no (0), small (1), moderate (2), or strong (3) differences. In addition, the relative number of participants achieving leg symmetry (≥ 90%) and normal performance (≥ 90% of the average performance of the non-dominant leg of controls) were compared between groups (chi-squared tests, P < 0.05). RESULTS: We observed no-to-moderate leg differences within ACL-IB (moderate difference in hops) and within ACL-R (moderate difference in knee proprioception), no leg differences between patient groups, no-to-small leg differences between ACL-IB and controls, and no leg differences between ACL-R and controls in functional performance. However, two patients in ACL-IB and ACL-R, respectively, passed the hop pretest only with their uninvolved leg, and fewer patients after ACL-IB and ACL-R than controls reached a leg symmetry and normal leg performance of controls in SLH (P < 0.001). CONCLUSIONS: Functional performance seems to be comparable 2 years postoperatively between ACL-IB and ACL-R for a specific subgroup of patients (i.e., proximal ACL tears, moderate activity level). However, the presumed advantage of comparable functional outcome with preserved knee structures after augmented ACL repair compared with ACL-R, and the tendency of both patient groups toward leg asymmetry and compromised single-leg hop performance in the involved legs, warrants further investigation. Level of Evidence Level III, case-control study. Trial registration clinicaltrials.gov, NCT04429165 (12/09/2020). Prospectively registered, https://clinicaltrials.gov/ct2/show/NCT04429165 .

The First Case of Bridge-Enhanced Anterior Cruciate Ligament (ACL) Repair (BEAR) Procedure in Mississippi.

In the past, surgical treatment of anterior cruciate ligament (ACL) tears has mainly involved reconstruction using allografts and autografts. The relatively new FDA-approved bridge-enhanced ACL repair (BEAR) procedure allows the body to use its innate healing properties to help repair the ACL using an absorbable protein-based implant. The procedure is currently being offered by surgeons in 44 states. This case describes the first BEAR procedure performed in the state of Mississippi. A 47-year-old female of normal BMI presented to the orthopedic clinic with a chief complaint of right knee pain. The patient stated that she felt unstable on the injured knee, and the patient had positive anterior drawer and Lachman's tests on physical examination. MRI of the knee one month after injury revealed full-thickness ACL rupture. The patient underwent arthroscopic bridge-enhanced ACL repair in the right knee 43 days after the initial injury. The patient reported positive progress in her healing process at her three-month follow-up, and MRI at the three-month follow-up showed successful repair of the patient's ACL. At six months post-operatively, the patient reported that she is still doing well, and she feels that the stability of her right knee has improved. This case highlights an early trend towards repairs instead of reconstructions in ACL injuries for candidates that meet the following requirements: within 50 days of injury and have an intact tibial stump as recommended by the implant manufacturers.

Primary anterior cruciate ligament repair: Current concepts.

The renewed interest in ACL repair over the last two decades stems from advances in modern arthroscopic techniques and clinical studies that have provided evidence that the ACL can reliably heal, and patients can return to sport at a comparable rate to ACL reconstruction patients. The ability to maintain and utilize native ACL tissue, with proprioceptive capabilities, and the smaller drill tunnels needed to repair an ACL leads to an overall less invasive procedure and improved early rehabilitation. Additionally, repair avoids a variety of comorbidities associated with autograft harvest. This current concept review details modern techniques of ACL repair and their current studies, a review on the use of biologic enhancement in ACL repair, and other considerations to appropriately integrate ACL repair into the sports medicine orthopaedic surgeon's practice.

Return to Sports After ACL Augmentation With Anterolateral Reconstruction (ALR) Harvesting Gracilis Only Compared With ACL Reconstruction With ALR Harvesting Both Hamstring Tendons.

BACKGROUND: Anterior cruciate ligament (ACL) repair (ACL-Rp) is known to be a valuable alternative to ACL reconstruction (ACL-Rc) in selected indications. The majority of the ACL-Rp techniques recommend the use of a synthetic brace. The use of the gracilis allows both a biological internal brace and anterolateral ligament reconstruction (ALR). PURPOSE: The primary objective was to compare the early ability to return to sports between patients who underwent ACL-Rp using a gracilis autograft as an internal brace augmentation with ALR and patients who underwent the conventional ACL-Rc with ALR technique sacrificing both the gracilis and the semitendinosus. The secondary objective was to compare the failure rate, clinical scores, and return to sports at a minimum follow-up of 2 years. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective analysis was undertaken. A total of 49 patients who underwent ACL-Rp with ALR between December 2018 and May 2019 were propensity matched at a 1:1 ratio to those who underwent ACL-Rc with ALR during the same period. The decision to perform ACL-Rp with ALR was based on preoperative selection and intraoperative arthroscopic findings: proximal avulsion tear, partial ACL tear, low- to midlevel sports participation, and good tissue quality. The ability to return to sports was assessed using isokinetic tests and the Knee Santy Athletic Return to Sport test functional test at 6 months postoperatively. At the final follow-up, knee laxity parameters, return to sports, and clinical outcome (Lysholm score, Tegner Activity Scale score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Anterior Cruciate Ligament-Return to Sport after Injury score) were recorded. RESULTS: The ACL-Rp group had significantly less hamstring strength deficit when compared with their counterparts who underwent ACL-Rc (0.2% vs 10.2% in concentric, P < .001; 2.5% vs 14% in eccentric, P < .001). The mean Knee Santy Athletic Return to Sport test score was significantly higher in the ACL-Rc group (69.7% ± 16.6% [range, 19%-100%] vs 61% ± 16.8% [range, 19%-100%]; P = .001). In the ACL-Rp group, 61% (30/49) of the patients were authorized to return to pivot sports versus 41% (20/49) in the ACL-Rc group (P = .04). At a mean final follow-up of 31.4 ± 3.5 months, no significant differences were demonstrated between groups with respect to clinical scores and knee laxity parameters. There was a trend for a higher failure rate in the ACL-Rp group without any significance (ACL-Rp: 6.1% [3/49] vs ACL-Rc: 0%; P = .08). CONCLUSION: At 6 months after operation, harvesting only the gracilis with this ACL-Rp and augmentation with ALR technique was linked to a better early ability to return to sports compared with the ACL-Rc with ALR technique harvesting both the gracilis and semitendinosus. This technique had a limited effect on early flexion strength and provided a satisfactory rerupture rate.

The Anterior Cruciate Ligament: Principles of Treatment.

The anterior cruciate ligament (ACL) is a crucial connective tissue in the knee joint (tibiofemoral joint). Although the surgical anatomy of this ligament has been studied and interpreted for decades, it remains a topic of discussion among surgeons. The ACL has two bundles, the anteromedial (AM) and the posterolateral (PL) bundle. ACL tears are among the most frequently sustained injuries to the tibiofemoral joint. The ACL is an important rotational stabilizer of the knee joint. The human knee joint can be classified as a complex structure, as it has many ligaments supporting its stability and ensuring required joint mobility. Previously, the outcomes of primary ACL surgery were poor; however, with time, the modalities have improved substantially. There are two methods of performing the reconstruction procedure, the single-bundle method, in which only the AM bundle is reconstructed, and the double-bundle method, in which both the AM and PL bundles of the ACL are reconstructed. Double bundle arthroscopic ACL reconstruction has been recognized as the gold standard procedure. The grafts used for the reconstruction procedure are the tendon of the patella graft and the grafts of the hamstrings. However, one of the drawbacks of performing this surgery is the development of complications, like osteoarthritis. This complication is observed majorly in sports professionals. This article aims to sum up the anatomy of the ACL, its regular tears, the various surgical aspects of managing it, and the advancement of treatment options in the past centuries. Although much has been achieved, detailed scientific studies should be carried out to improve the prognosis and decrease the risk of development of complications.

Machine learning can accurately predict risk factors for all-cause reoperation after ACLR: creating a clinical tool to improve patient counseling and outcomes.

PURPOSE: Identifying predictive factors for all-cause reoperation after anterior cruciate ligament reconstruction could inform clinical decision making and improve risk mitigation. The primary purposes of this study are to (1) determine the incidence of all-cause reoperation after anterior cruciate ligament reconstruction, (2) identify predictors of reoperation after anterior cruciate ligament reconstruction using machine learning methodology, and (3) compare the predictive capacity of the machine learning methods to that of traditional logistic regression. METHODS: A longitudinal geographical database was utilized to identify patients with a diagnosis of new anterior cruciate ligament injury. Eight machine learning models were appraised on their ability to predict all-cause reoperation after anterior cruciate ligament reconstruction. Model performance was evaluated via area under the receiver operating characteristics curve. To explore modeling interpretability and radiomic feature influence on the predictions, we utilized a game-theory-based method through SHapley Additive exPlanations. RESULTS: A total of 1400 patients underwent anterior cruciate ligament reconstruction with a mean postoperative follow-up of 9 years. Two-hundred and eighteen (16%) patients experienced a reoperation after anterior cruciate ligament reconstruction, of which 6% of these were revision ACL reconstruction. SHapley Additive exPlanations plots identified the following risk factors as predictive for all-cause reoperation: diagnosis of systemic inflammatory disease, distal tear location, concomitant medial collateral ligament repair, higher visual analog scale pain score prior to surgery, hamstring autograft, tibial fixation via radial expansion device, younger age at initial injury, and concomitant meniscal repair. Pertinent negatives, when compared to previous studies, included sex and timing of surgery. XGBoost was the best-performing model (area under the receiver operating characteristics curve of 0.77) and outperformed logistic regression in this regard. CONCLUSIONS: All-cause reoperation after anterior cruciate ligament reconstruction occurred at a rate of 16%. Machine learning models outperformed traditional statistics and identified diagnosis of systemic inflammatory disease, distal tear location, concomitant medial collateral ligament repair, higher visual analog scale pain score prior to surgery, hamstring autograft, tibial fixation via radial expansion device, younger age at initial injury, and concomitant meniscal repair as predictive risk factors for reoperation. Pertinent negatives, when compared to previous studies, included sex and timing of surgery. These models will allow surgeons to tabulate individualized risk for future reoperation for patients undergoing anterior cruciate ligament reconstruction. LEVEL OF EVIDENCE: III.

Altered Knee Loading Following Primary ACL Repair versus ACL Reconstruction.

Background: ACL repair (ACL-r) has recently gained renewed clinical interest for treatment of ACL tears. ACL-r has several potential benefits over ACL reconstruction (ACL-R) including maintaining the native ACL innervation and blood supply, no graft site morbidity, and possible improved knee biomechanics and decrease in osteoarthritis. The purpose of this study was to assess for differences in metrics of knee joint loading during a single limb squat task between individuals following a primary ACL-r versus those who underwent a standard ACL-R with a patella bone-tendon-bone autograft. Study type: Case Control Study. Methods: The ACL-r group [n: 15, age(yrs): 38.8±13.9] sustained a proximal ACL disruption that was amenable to repair, while the ACL-R group [n: 15, age(yrs): 25.60±1.7] underwent primary reconstruction with patella bone-tendon-bone autograft. At 12-weeks post-operation, both groups completed the IKDC questionnaire and biomechanical testing during performance of the single limb squat. Bilateral peak knee extension moment and total knee joint power as a measure of eccentric loading (contraction) during the descent phase of the squat were calculated on the surgical and non-surgical limb and averaged across the middle three of five trials. Participants also completed quadriceps strength testing on both limbs three months after surgery on an isokinetic dynamometer at 60°/sec. LSI (Limb Strength Index) was calculated for all variables. Separate ANCOVAs were performed on each biomechanical variable to examine differences between groups. Results: The ACL-r had a significantly greater peak knee extension moment LSI (ACL-r: 78.46±5.79%; ACL-R: 56.86±5.79%; p=0.019, ηp2=.186) and total knee joint power LSI (ACL-r: 72.47±7.39%; ACL-R: 39.70±7.39%, p=0.006, ηp2=.245) than the ACL-R group. The ACL-r also had a significantly greater quadriceps LSI than the ACL-R group (ACL-r: 66.318±4.61%, ACL-R: 48.03±4.61%, p=0.013, ηp2=.206). Conclusions: Individuals following ACL-r demonstrate increased knee joint loading symmetry during a single leg squat task and greater quadriceps strength symmetry at 12 weeks post-surgery compared to those who underwent ACL-R. Level of Evidence: 3.

Augmenting ACL Repair With Suture Tape Improves Knee Laxity: A Biomechanical Study.

Background: Anterior cruciate ligament (ACL) repair is an alternative to reconstruction; however, suture tape support may be necessary to achieve adequate outcomes. Purposes: To investigate the influence of suture tape augmentation (STA) of proximal ACL repair on knee kinematics and to evaluate the effect of the 2 flexion angles of suture tape fixation. Study Design: Controlled laboratory study. Methods: Fourteen cadaveric knees were tested using a 6 degrees of freedom robotic testing system under anterior tibial (AT) load, simulated pivot-shift (PS) load, and internal rotation (IR) and external rotation loads. Kinematics and in situ tissue forces were evaluated. Knee states tested were (1) ACL intact, (2) ACL cut, (3) ACL repair with suture only, (4) ACL repair with STA fixed at 0° of knee flexion, and (5) ACL repair with STA fixed at 20° of knee flexion. Results: ACL repair alone did not restore the intact ACL AT translation at 0°, 15°, 30°, or 60° of flexion. Adding suture tape to the repair significantly decreased AT translation at 0°, 15°, and 30° of knee flexion but not to the level of the intact ACL. With PS and IR loadings, only ACL repair with STA fixed at 20° of flexion was not significantly different from the intact state at all knee flexion angles. ACL suture repair had significantly lower in situ forces than the intact ACL with AT, PS, and IR loadings. With AT, PS, and IR loadings, adding suture tape significantly increased the in situ force in the repaired ACL at all knee flexion angles to become closer to that of the intact ACL state. Conclusion: For complete proximal ACL tears, suture repair alone did not restore normal knee laxity or normal ACL in situ force. However, adding suture tape to augment the repair resulted in knee laxity closer to that of the intact ACL. STA with fixation at 20° of knee flexion was superior to fixation with the knee in full extension. Clinical Relevance: The study findings suggest that ACL repair with STA fixed at 20° could be considered in the treatment of femoral sided ACL tears in the appropriate patient population.

Graft failure and revision rate after ACL repair with dynamic intraligamentary stabilization. One-year results of a prospective case series of 155 patients.

PURPOSE: The aim of this study was to assess graft failure, revision rate, and functional outcomes after treatment of acute ACL rupture with dynamic intraligamentary stabilization (DIS) Ligamys device one year post surgery. Additionally, differences in functional outcome between patients with and without anteroposterior laxity were assessed. It was hypothesized that the failure rate of DIS was non-inferior to that of previously reported ACL reconstruction (10%). METHODS: In this prospectively designed multicenter study, including patients with an acute ACL rupture, DIS was performed within 21 days after rupture. Primary outcome was failure of the graft at 1 year post surgery, defined as 1) re-rupture of the graft, 2) revision of DIS, or 3) a > 3 mm side-to-side difference in anterior tibial translation compared to the non-operated knee (∆ATT), measured by the KT1000 device. Additional analysis was performed using a 5 mm threshold. The subjective International Knee Documentation Committee Score (IKDC) and Numerical Rating Scales (NRS) for pain and confidence were used to evaluate functional outcome. RESULTS: A total of 155 patients were included with a mean age at surgery of 27.8 years (SD 9.4). The mean interval from rupture to DIS was 16.4 days (SD 5.2). At a median follow-up of 13 months (IQR 12-18) the failure rate of the graft was 30.2% (95%CI:22.0-39.4); 11 patients (7%) required secondary reconstructive surgery and of the 105 patients who attended ATT measurement, 24 patients (23%) had an ∆ATT > 3 mm. Secondary analysis, based on a 5 mm threshold, revealed a failure rate of 22.4% (95%CI: 15.2; 31.1). A total of 39 patients (25%) reported at least one complication, comprising mainly arthrofibrosis, traumatic re-rupture and pain. In these patients, removal of the monoblock was performed in 21 cases (13.5%). At follow-up no significant differences in functional outcomes between patients with ∆ATT > 3 mm and stable ATT were observed. CONCLUSION: This prospective multicenter study found a high failure rate at one year follow-up of 30% (7% revision surgery and 23% > 3 mm side-to-side difference in anterior tibial translation) in patients treated by primary repair of the ACL with DIS, and did therefore not demonstrate non-inferiority to ACL reconstruction. For patients who did not require secondary reconstructive surgery, this study found good functional outcomes, also in case of persistent anteroposterior knee laxity (∆ATT > 3 mm). LEVEL OF EVIDENCE: Level IV.

Bridge enhanced ACL repair vs. ACL reconstruction for ACL tears: A systematic review and meta-analysis of comparative studies.

INTRODUCTION: Anterior cruciate ligament (ACL) tear is one of the most frequent ligamentous injuries. The gold standard for ACL tears is autograft reconstruction. However, ACL repair has regained enthusiasm with more recent results showing comparable outcomes to its reconstructive counterpart. METHODS: PubMed, Cochrane, and Google Scholar (pp. 1-20) were searched until November 2022. The clinical outcomes consisted of the International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), the side-to-side difference in Anteroposterior (AP) knee laxity, the forces of the hamstring, quadriceps, and hip abduction as well as hopping tests. RESULTS: Only two studies were included in this meta-analysis. ACL repair was shown to have better Hamstrings strength. The rest of the analyzed outcomes were comparable. DISCUSSION: This is the first meta-analysis comparing these two treatments. The ACL repair showed no differences in muscle strength (quadriceps and hip abductors), postoperative knee scores, and knee joint laxity when compared to ACL reconstruction. However, it showed better hamstring strength. Further randomized clinical studies will be needed to compare both of these techniques.

Primary Proximal ACL Repair: A Biomechanical Evaluation of Different Arthroscopic Suture Configurations.

Purpose: Several suture techniques have been described in the past for direct ACL repair with poor healing capacity and a high re-rupture rate. Therefore, we investigated a refixation technique for acute primary proximal ACL repair. The purpose of this study is to compare the biomechanical properties of different suture configurations using a knotless anchor. Methods: In this study, 35 fresh-frozen porcine knees underwent proximal ACL refixation. First, in 10 porcine femora, the biomechanical properties of the knotless anchor, without the ligament attached, were tested. Then, three different suture configurations were evaluated to reattach the remaining ACL. Using a material testing machine, the structural properties were evaluated for cyclic loading followed by loading to failure. Results: The ultimate failure load of the knotless anchor was 198, 76 N ± 23, 4 N significantly higher than all of the tested ACL suture configurations. Comparing the different configurations, the modified Kessler-Bunnell suture showed significant superior ultimate failure load, with 81, 2 N ± 15, 6 N compared to the twofold and single sutures (50, 5 N ± 14 N and 37, 5 ± 3, 8 N). In cyclic loading, there was no significant difference noted for the different configurations in terms of stiffness and elongation. Conclusions: The results of this in vitro study show that when performing ACL suture using a knotless anchor, a modified Kessler-Bunnell suture provides superior biomechanical properties than a single and a twofold suture. Within this construct, no failure at the bone-anchor interface was seen. Clinical relevance: Since primary suture repair techniques of ACL tears have been abandoned because of inconsistent results, ACL reconstruction remains the gold standard of treating ACL tears. However, with the latest improvements in surgical techniques, instrumentation, hardware and imaging, primary ACL suture repair might be a treatment option for a select group of patients. By establishing an arthroscopic technique in which proximal ACL avulsion can be reattached, the original ACL can be preserved by using a knotless anchor and a threefold suture configuration. Nevertheless, this technique provides an inferior ultimate failure load compared to graft techniques, so a careful rehabilitation program must be followed if using this technique in vivo.