Patellar versus hamstring tendons in anterior cruciate ligament reconstruction: A meta-analysis

Superior Biological Healing of Hamstring Autografts Compared with Tibialis Allografts after Anterior Cruciate Ligament Reconstruction: A Propensity Score Matching Analysis Based on Second-Look Arthroscopy

Background and Objectives: Remodeling and healing of the graft are crucial processes for long-term graft survival after anterior cruciate ligament reconstruction (ACLR). However, few studies have objectively evaluated the differences in graft healing between autografts and allografts. This study aimed to compare the status of the anterior cruciate ligament (ACL) grafts between hamstring tendon (HT) autografts and tibialis anterior tendon (TAT) allografts using second-look arthroscopy. Materials and Methods: The outcomes of 193 consecutive patients (153 males and 40 females, with an average age of 30.38 and BMI of 25.43 kg/m2) who underwent second-look arthroscopy following primary ACLR were retrospectively reviewed. Prior to participating in this study, all patients provided written informed consent. The patients were divided into two groups: those with HT autografts and those with TAT allografts. Confounding factors were matched between the two groups using propensity score matching (PSM). ACL graft status was assessed during second-look arthroscopy using a numeric scale system based on the degree of four parameters: graft tension, continuity, synovium coverage, and vascular marking. Clinical outcomes were assessed using the Lysholm and International Knee Documentation Committee (IKDC) scores. Graft status and clinical outcomes were compared between the two groups. Additionally, a subgroup analysis based on the timing of the second-look arthroscopy (12-24 months vs. >24 months after the initial ACLR) was conducted. Results: After PSM, 62 patients were included in each group. The second-look arthroscopy was conducted at 23.6 ± 6.6 months for the HT group and at 24.0 ± 7.9 months for the TAT group (p = 0.749). The continuity and tension of the ACL graft were not significantly different between the two groups (p = 0.146 and 0.075, respectively). However, the TAT group exhibited significantly inferior synovial coverage and vascular marking of the ACL graft compared with the HT group (p = 0.021 and 0.007, respectively). These findings were consistent regardless of the timing of the second-look arthroscopy. Clinical outcomes, according to the Lysholm and IKDC scores, significantly improved in both groups with no significant differences (p = 0.386 and 0.733, respectively). Conclusions: Although there were no differences in graft tension and continuity between HT autografts and TAT allografts, the biological healing of ACL grafts, in terms of synovialization and vascularization, was superior in HT autografts compared to TAT allografts.

Anterior Cruciate Ligament Reconstruction in French Army: Return to Prior Level of Running on Selected Military Tests

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is frequently encountered in athletes as well as in military personnel. In civilian population, many studies have looked at the return to sport, but return to duty in Army is a topic that requires further research.The purpose of this study was to determine through annual military fitness tests in real conditions, the return to sport in soldiers after ACL reconstruction and factors influencing failure.

MATERIALS AND METHODS

This was a retrospective comparative study. Patients were all soldiers and had followed up in a Military Hospital. The SUCCESS group was military personnel who obtained a result of the specific aptitude test greater than or equal to this same test carried out before reconstruction of the ACL, the FAILURE group comprised the others. Results of the annual specific aerobic fitness tests were collected before and after ACL reconstruction. Preoperative epidemiological data, intraoperative information, and isokinetic test results were collected.

RESULTS

One hundred forty four soldiers were included between January 2011 and December 2017 (94.9% of men with a median age of 27.6 years); 40.3% obtained a result greater than or equal to the preoperative fitness test after ACL reconstruction. Among the soldiers who did not regain their performance, 24.3% were declared unfit or discharged. In the FAILURE group, we found patients with a higher body mass index (25.5 vs. 24.4; P = .04), less patients with isokinetic deficit < 30% on the knee flexors and extensors (26.6% vs. 62.9%; P < .01), more long sick leave (39.5% vs. 13.7%; P < .01), and late resumption of military activities (10.5 vs. 8.9 months; P < .01).

CONCLUSION

Rupture of ACL has a significant impact on the operational capacity of the French army. The proportion of return to the same level in annual specific fitness tests after ACL reconstruction is 40% among soldiers. Several variables are important to consider in the follow-up of these patients to optimize their recovery of sports performance and therefore their operational capacity.

Combined anterior cruciate ligament revision with reconstruction of the antero-lateral ligament does not improve outcome at 2-year follow-up compared to isolated acl revision; a randomized controlled trial

PURPOSE

It is essential to obtain rotational stability of the knee after anterior cruciate ligament reconstruction (ACL-R) and it is suggested that a supplementary reconstruction of the antero-lateral ligament (ALL-R) may supports this. Theoretically, ALL-R may be particularly advantageous to support revision of failed ACL-Rs. It was hypothesized that ACL revision combined with ALL-R will result in superior outcome compared to isolated ACL revision.

METHODS

The study was designed as a randomized controlled trial. Patients eligible for first time ACL revision were randomized to either isolated ACL revision (- ALL group) or ACL revision combined with a single-stranded allograft ALL-reconstruction (+ ALL group). Patient reported outcomes and function were evaluated at two-year follow-up by KNEES-ACL, KOOS, and Tegner activity scale. Objective knee laxity was evaluated at one-year follow-up using an instrumented Rolimeter test, the pivot shift test, and a manual Lachman test.

RESULTS

A total of 103 patients were enrolled with 49 patients randomized to the + ALL group and 54 patients in the - ALL group. There were no differences at baseline between groups regarding age, gender, body mass index, preoperative patient reported outcome scores and concomitant meniscus or cartilage injury. The ACL revision was performed with an allograft in 10 patients (20%) in the + ALL group and 8 patients (15%) in the -ALL group. At follow-up there was no significant difference between the groups in patient reported outcome scores and clinical knee laxity.

CONCLUSION

Supplementary ALL-R does not improve subjective outcome of first time ACL revision at two-years and clinical knee stability at one-year follow-up compared to isolated ACL revision.

LEVEL OF EVIDENCE

Level I.

Risk Factors for Revision or Rerupture After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

The rerupture or need for revision after anterior cruciate ligament reconstruction (ACLR) is a serious complication. Preventive strategies that target the early identification of risk factors are important to reduce the incidence of additional surgery.

PURPOSE

To perform a systematic review and meta-analysis to investigate risk factors for revision or rerupture after ACLR.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

Literature searches were performed in PubMed, Embase, and Web of Science from database inception to November 2021 and updated in January 2022. Quantitative, original studies reporting potential adjusted risk factors were included. Odds ratios (ORs) were calculated for potential risk factors.

RESULTS

A total of 71 studies across 13 countries with a total sample size of 629,120 met the inclusion criteria. Fifteen factors were associated with an increase in the risk of revision or rerupture after ACLR: male sex (OR, 1.27; 95% CI, 1.14-1.41), younger age (OR, 1.07; 95% CI, 1.05-1.08), lower body mass index (BMI) (OR, 1.03; 95% CI, 1.00-1.06), family history (OR, 2.47; 95% CI, 1.50-4.08), White race (OR, 1.32; 95% CI, 1.08-1.60), higher posterolateral tibial slope (OR, 1.15; 95% CI, 1.05-1.26), preoperative high-grade anterior knee laxity (OR, 2.30; 95% CI, 1.46-3.64), higher baseline Marx activity level (OR, 1.07; 95% CI, 1.02-1.13), return to a high activity level/sport (OR, 2.03; 95% CI, 1.15-3.57), an ACLR within less than a year after injury (OR, 2.05; 95% CI, 1.81-2.32), a concomitant medial collateral ligament (MCL) injury (OR, 1.62; 95% CI, 1.31-2.00), an anteromedial portal or transportal technique (OR, 1.36; 95% CI, 1.22-1.51), hamstring tendon (HT) autografts (vs bone-patellar tendon-bone [BPTB] autografts) (OR, 1.60; 95% CI, 1.40-1.82), allografts (OR, 2.63; 95% CI, 1.65-4.19), and smaller graft diameter (OR, 1.21; 95% CI, 1.05-1.38). The other factors failed to show an association with an increased risk of revision or rerupture after ACLR.

CONCLUSION

Male sex, younger age, lower BMI, family history, White race, higher posterolateral tibial slope, preoperative high-grade anterior knee laxity, higher baseline Marx activity level, return to a high activity level/sport, an ACLR within less than a year from injury, a concomitant MCL injury, an anteromedial portal or transportal technique, HT autografts (vs BPTB autografts), allografts, and smaller graft diameter may increase the risk of revision or rerupture after ACLR. Raising awareness and implementing effective preventions/interventions for risk factors are priorities for clinical practitioners to reduce the incidence of revision or rerupture after ACLR.

Cyclops lesions associated with both bundles and selective bundle repair of the anterior cruciate ligament

BACKGROUND

The remnant of a ruptured anterior cruciate ligament (ACL) can increase the risk of impingement or a cyclops lesion, which can increase challenges to proper tunnel placement.

PURPOSE

To evaluate the prevalence of cyclops lesions after ACL reconstruction and to assess the difference in the incidence of cyclops lesions between single-bundle repair and selective bundle repair of the ACL.

MATERIAL AND METHODS

This retrospective study included 151 patients who were diagnosed with an ACL tear after knee joint magnetic resonance imaging (MRI) who underwent ACL reconstruction surgery. MRI diagnosis of cyclops lesion formation was made if a soft-tissue mass was seen anteriorly in the intercondylar notch near the tibial insertion of the reconstructed ACL, based on sagittal T2-weighted (T2W) imaging. The size of the cyclops lesions was recorded as the largest diameter on the sagittal T2W imaging.

RESULTS

A cyclops lesion was detected in 74 (38.5%) cases. Cyclops lesions were detected more frequently in cases with single-bundle repair of the ACL, but the results were not statistically significant (P = 0.609). Compared with selective bundle repair, cyclops lesions had a significantly higher prevalence in the posterolateral (PL) bundle repair than in the anteromedial (AM) bundle repair (P = 0.027) based on MR images at 6-12 months after surgery.

CONCLUSION

The incidence of cyclops lesions did not differ significantly in single-bundle repair and selective bundle repair of ACL. However, selective PL bundle repair of the ACL showed a significantly increased incidence of cyclops lesions compared with selective AM bundle repair.

Tackling the Challenges of Graft Healing After Anterior Cruciate Ligament Reconstruction-Thinking From the Endpoint

Anterior cruciate ligament (ACL) tear is common in sports and accidents, and accounts for over 50% of all knee injuries. ACL reconstruction (ACLR) is commonly indicated to restore the knee stability, prevent anterior–posterior translation, and reduce the risk of developing post-traumatic osteoarthritis. However, the outcome of biological graft healing is not satisfactory with graft failure after ACLR. Tendon graft-to-bone tunnel healing and graft mid-substance remodeling are two key challenges of biological graft healing after ACLR. Mounting evidence supports excessive inflammation due to ACL injury and ACLR, and tendon graft-to-bone tunnel motion negatively influences these two key processes. To tackle the problem of biological graft healing, we believe that an inductive approach should be adopted, starting from the endpoint that we expected after ACLR, even though the results may not be achievable at present, followed by developing clinically practical strategies to achieve this ultimate goal. We believe that mineralization of tunnel graft and ligamentization of graft mid-substance to restore the ultrastructure and anatomy of the original ACL are the ultimate targets of ACLR. Hence, strategies that are osteoinductive, angiogenic, or anti-inflammatory should drive graft healing toward the targets. This paper reviews pre-clinical and clinical literature supporting this claim and the role of inflammation in negatively influencing graft healing. The practical considerations when developing a biological therapy to promote ACLR for future clinical translation are also discussed.

The effect of lateral extra-articular tenodesis on in vivo cartilage contact in combined anterior cruciate ligament reconstruction

PURPOSE

Lateral extra-articular tenodesis (LET) may confer improved rotational stability after anterior cruciate ligament reconstruction (ACLR). Little is known about how LET affects in vivo cartilage contact after ACLR. The aim of this study was to investigate the effect of LET in combination with ACLR (ACLR + LET) on in vivo cartilage contact kinematics compared to isolated ACLR (ACLR) during downhill running. It was hypothesised that cartilage contact area in the lateral compartment would be larger in ACLR + LET compared with ACLR, and that the anterior-posterior (A-P) position of the contact center on the lateral tibia would be more anterior after ACLR + LET than after ACLR.

METHODS

Twenty patients were randomly assigned into ACLR + LET or ACLR during surgery (ClinicalTrials.gov:NCT02913404). At 6 months and 12 months after surgery, participants were imaged during downhill running using biplane radiography. Tibiofemoral motion was tracked using a validated registration process. Patient-specific cartilage models, obtained from 3 T MRI, were registered to track bone models and used to calculate the dynamic cartilage contact area and center of cartilage contact in both the medial and lateral tibiofemoral compartments, respectively. The side-to-side differences (SSD) were compared between groups using a Mann-Whitney U test.

RESULTS

At 6 months after surgery, the SSD in A-P cartilage contact center in ACLR + LET (3.9 ± 2.6 mm, 4.4 ± 3.1 mm) was larger than in ACLR (1.2 ± 1.6 mm, 1.5 ± 2.0 mm) at 10% and 20% of the gait cycle, respectively (p < 0.01, p < 0.05). There was no difference in the SSD in cartilage contact center at 12 months after surgery. There was no difference in SSD of cartilage contact area in the medial and lateral compartments at both 6 and 12 months after surgery. There were no adverse events during the trial.

CONCLUSION

LET in combination with ACLR may affect the cartilage contact center during downhill running in the early post-operation phase, but this effect is lost in the longer term. This suggests that healing and neuromuscular adaptation occur over time and may also indicate a dampening of the effect of LET over time. (337 /350 words) LEVEL OF EVIDENCE: Level II.

Quadriceps and hamstring tendon autografts in ACL reconstruction yield comparably good results in a prospective, randomized controlled trial

INTRODUCTION

Comparable data of functional outcomes of anterior cruciate ligament reconstruction using either hamstring- or quadriceps tendon grafts is controversial. This prospective, randomized controlled trial aims to provide data comparing both grafts regarding the functional outcome.

MATERIALS AND METHODS

A two centre trial involving symptomatic patients 18 years of age or older with an anterior cruciate ligament tear was conducted. We randomly assigned 27 patients to quadruple hamstring tendon reconstruction and 24 to quadriceps tendon reconstruction. The patients were evaluated preoperatively, at 3, 6, 12 and 24 months post-surgery. The primary outcome parameter was the side-to-side knee laxity measured with an arthrometer. Secondary outcomes included results in the International Knee Documentation Committee (IKDC) and Lysholm Scores and isokinetic testing of strength in knee extension and flexion.

RESULTS

Forty-four patients (86%) completed the 2-year follow-up. There was significantly improved knee stability at all time intervals with no difference between the two study groups. The manual side-to-side displacement improved by 4.7 ± 3.0 mm in patients with hamstring tendon reconstruction and 5.5 ± 2.9 mm in patients with quadriceps tendon reconstruction. In addition, muscle strength and outcome scores (IKDC and Lysholm Score) did not show any differences between the hamstring tendon group and the quadriceps tendon group. Patients in the hamstring tendon group returned to their pre-injury activity level after 95.2 ± 45.5 days while patients in the quadriceps tendon group needed 82.1 ± 45.6 days.

CONCLUSION

Quadriceps and hamstring tendon autografts yield comparably good results in primary anterior cruciate ligament reconstruction.

A Systematic Approach for Stronger Documentation of Anterior Cruciate Ligament Graft Choice

Numerous studies have focused on determining the optimal choice between the two most used anterior cruciate ligament (ACL) reconstruction autografts. In order to address this matter, we performed a systematic review of every meta-analysis published on the PubMed platform between 2001 and 2020, comparing the functional outcomes, the static stability parameters, as well as the postoperative and long-term complications of the patellar tendon (BPTB) autograft and hamstrings (HT). We retrieved a total of 26 meta-analyses that met our criteria, and the characteristics and outcomes of every meta-analysis, as well as subgroup analysis regarding the type of the study design, number of strands of HT autograft, and fixation method, were extensively recorded. The majority of the meta-analyses showed that there were no significant differences between BPTB and HT in terms of functional outcomes and static stability parameters while HT autografts seem to be superior to BPTB regarding kneeling pain and anterior knee pain. Other outcomes seem to be affected by the number of strands of the HT autograft, the fixation technique, and the type of study design, indicating superiority of the four-strand HT autograft with the use of an extra-cortical button fixation. Overall, there is no clear superiority of BPTB over HT autografts for ACL reconstruction, as both types present similar outcomes in the majority of postoperative parameters. Autograft selection should be individualized according to each patient's needs and more RCTs are warranted in order to reach safer results on the appropriate autograft type.

No Difference in Functional Outcomes When Lateral Extra-Articular Tenodesis Is Added to Anterior Cruciate Ligament Reconstruction in Young Active Patients: The Stability Study

PURPOSE

To assess the functional outcomes of patients included in the Stability Study randomized controlled trial comparing anterior cruciate ligament reconstruction (ACLR) alone with ACLR with lateral extra-articular tenodesis (LET) at 6, 12, and 24 months postoperatively.

METHODS

Six hundred eighteen patients undergoing ACLR, all under the age of 25 years either returning to contact pivoting sport or displaying signs of high-grade rotatory laxity or generalized ligamentous laxity, were randomly assigned to receive ACLR alone or ACLR plus LET. A total of 356 of these patients were randomized at centers participating in the functional assessments. Our primary outcome was Limb Symmetry Index, calculated using a series of 4-hop tests at 6, 12, and 24 months postoperatively. Secondary outcome measures included pain, patient-reported function, and isokinetic strength testing.

RESULTS

We found no statistically significant difference in the proportion of patients either unwilling or unfit to complete the hop testing in the ACLR alone or ACLR with LET group at 6 months (40 vs 40 respectively; P = 1.00), 12 months (25 vs 27; P = .76), and 24 months (21 vs 23; P = .87). Of those who completed hop testing, there were no statistically significant differences between groups in Limb Symmetry Index at 6, 12, or 24 months. Self-reported function (Lower Extremity Functional Score) significantly favored the ACLR alone group at 3 (P = .01) and 6 months (P = .02) postoperative but was similar by 12 months postoperative. Pain scores (P4) also showed a statistically significant difference in favor of the ACL alone group, but this also resolved by 6 months. Quadriceps peak torque (P = .03) and average power (P = .01) were also significantly different in favor of the ACLR alone group at 6 months postoperative; however, these were similar between groups by 12 months postoperative (P = .11 and P = .32, respectively).

CONCLUSIONS

The addition of a LET to ACLR results in slightly increased pain, a mild reduction in quadriceps strength, and reduced subjective functional recovery up to 6 months postoperatively. However, these differences do not have any impact on objective function as measured by hop test limb symmetry index.

LEVEL OF EVIDENCE

I, Randomized Controlled Trial.

Is anterior cruciate ligament graft rupture (after successful anterior cruciate ligament reconstruction and return to sports) actually a graft failure or a re-injury?

PURPOSE

The objective of this study is to discuss the fact that whether graft rupture after successful anterior cruciate ligament (ACL) reconstruction surgery is due to graft failure or re-injury to the reconstructed ACL.

METHODS

In total, 340 sportspersons, meeting our inclusion criteria, were assessed for rupture of ipsilateral ACL graft and ACL injury of the contralateral knee. Patients with ipsilateral ACL graft rupture were labelled as group 1, while those with contralateral ACL injury were labelled as group 2. Both groups were compared for potential risk factors for ACL injury, and statistical analysis was performed to study whether the graft acted as an additional risk factor.

RESULTS

Of the 340 sportspersons, 25 patients suffered a total of 26 injuries. Ipsilateral graft rupture rate was 2.4% (8 of 340) at a mean follow-up of 25.5 ± 40.57 months, and the contralateral ACL injury rate was 5.3% (18 of 340) at a mean follow-up of 18.11 ± 19.97 months, with an overall re-injury rate of 7.6%. Both groups were comparable for risk factors for ACL injury: age ( p = 0.255), gender ( p = 0.534), mode of re-injury ( p = 0.523), level of sports activity, type of graft used ( p = 0. 918), graft diameter ( p = 0.607), duration from injury to index surgery ( p = 0.492), duration from index surgery to re-injury ( p = 0.638), timing of return to sports after index surgery ( p = 0.303), duration of sporting activity before second injury ( p = 0.657), and Tegner's level of sports activity ( p = 0.486).

CONCLUSION

Because the rate of contralateral ACL injury is higher than the ipsilateral graft rupture and the risk factors for ACL injury are comparable in both groups at a follow-up period, which is suggestive of ligamentization of the graft, we suggest that it might be an ACL re-injury rather than graft failure. Level of Evidence: Level III (Retrospective cohort study).

Effect of Graft Choice on Revision and Contralateral Anterior Cruciate Ligament Reconstruction: Results From the New Zealand ACL Registry

BACKGROUND

The patellar tendon is often considered the "gold standard" graft for reducing the risk of graft rupture after anterior cruciate ligament (ACL) reconstruction. However, its use may also be associated with an increased risk of injury to the contralateral ACL.

PURPOSE

To clarify the association between graft choice and the risk of revision and contralateral ACL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Prospective data captured by the New Zealand ACL Registry between April 2014 and December 2018 were reviewed. All primary ACL reconstructions performed using either a hamstring tendon or patellar tendon autograft were included. Cox regression survival analysis adjusting for patient factors was performed to compare the risk of revision and contralateral ACL reconstruction between the hamstring tendon graft and the patellar tendon graft.

RESULTS

A total of 7155 primary ACL reconstructions were reviewed, of which 5563 (77.7%) were performed using a hamstring tendon graft and 1592 (22.3%) were performed using a patellar tendon graft. Patients with a hamstring tendon graft had a revision rate of 2.7% compared with 1.3% in patients with a patellar tendon graft (adjusted hazard ratio [HR], 2.51; 95% CI, 1.55-4.06; P < .001). The patellar tendon graft was associated with an increased risk of contralateral ACL reconstruction compared with the hamstring tendon graft (adjusted HR, 1.91; 95% CI, 1.15-3.16; P = .012). The number needed to treat (NNT) with a patellar tendon graft to prevent 1 revision was 73.6. However, the NNT with a hamstring tendon graft to prevent 1 contralateral reconstruction was 116.3.

CONCLUSION

Use of a patellar tendon graft reduced the risk of graft rupture but was associated with an increased risk of injury to the contralateral ACL. Adequate rehabilitation and informed decision making on return to activity and injury prevention measures may be important in preventing subsequent injury to the healthy knee.

Reliability and methodology of quantitative assessment of harvested and unharvested patellar tendons of ACL injured athletes using ultrasound tissue characterization

Background

Ultrasound tissue characterization (UTC) imaging has been previously used to describe the characteristics of patellar and Achilles tendons. UTC imaging compares and correlates successive ultrasonographic transverse tendon images to calculate the distribution of four color-coded echo-types that represent different tendon tissue types. However, UTC has not been used to describe the characteristics of patellar tendons after anterior cruciate ligament reconstruction (ACLR). The aim of this cross-sectional study was to assess the intra and inter-rater reliability of the UTC in unharvested and harvested patellar tendons of patients undergoing ACLR.

Methods

Intra and inter-rater reliability of both UTC data collection and analysis were assessed. Ten harvested and twenty unharvested patellar tendons from eighteen participants were scanned twice by the same examiner. Eleven harvested and ten unharvested patellar tendons from sixteen participants were scanned and analyzed twice by two different examiners. Twenty harvested and nineteen unharvested patellar tendons from twenty-three participants were analyzed twice by two examiners.

Results

Quantification of the proportion of echo-types I, II, III and IV in the areas of interest: (1) patella apex, (2) proximal tendon, (3) mid tendon, (4) distal tendon, and overall tendon of harvested and unharvested patellar tendons all displayed excellent intra-rater reliability (ICC_2,1: 0.94 to 0.99), excellent inter-rater reliability for harvested and unharvested patellar tendon scanning and analysis (ICC_2,1: 0.89 to 0.98), and excellent inter-rater reliability for analysis (ICC_2,1: 0.95 to 0.99). Intra-rater reliability for the measure of volume was good (ICC_2,1: 0.69 harvested, 0.67 unharvested), whilst mixed results were observed for the measure of mid tendon thickness (ICC_2,1: 0.88 harvested, 0.57 unharvested). Inter-rater reliability for scanning and analysis was good for volume (ICC_2,1: 0.67) and excellent for thickness (ICC_2,1: 0.97), while the inter-rater reliability for analysis was fair to poor for volume (ICC_2,1: 0.59 harvested, 0.30 unharvested), and excellent to poor for mid tendon thickness (ICC_2,1: 0.85 harvested, 0.24 unharvested).

Conclusion

UTC imaging is a reliable tool to characterize the quality of most aspects of unharvested and harvested patellar tendons in subjects undergoing ACLR.

Identifying candidates for arthroscopic primary repair of the anterior cruciate ligament: A case-control study

INTRODUCTION

There has been a recent resurgence of interest in arthroscopic primary repair of proximal anterior cruciate ligament (ACL) tears. Patient selection is critical but not much is currently known on what predicts the possibility of repair. Goal of this study was therefore to assess predictive factors for the possibility of arthroscopic primary ACL repair.

METHODS

In this retrospective case-control study, all patients undergoing ACL surgery in a ten-year interval were included. Patients were treated with primary repair if there was a proximal tear and good tissue quality, or otherwise underwent ACL reconstruction. Collected data were age, gender, BMI, injury-to-surgery delay, injury mechanism and concomitant injuries. Receiver operating characteristic curves were used to find cutoff values, and all significant dependent variables were used in multivariate logistic analysis to assess independent predictors for the possibility of primary repair.

RESULTS

Three hundred sixty-one patients were included, of which in 158 patients (44%) primary repair was possible. Multivariate analysis (R² = 0.340, p < 0.001) showed that age > 35 years (Odds ratio [OR] 4.2, 95% CI 2.4-7.5,p < 0.001), surgery within 28 days (OR 3.3, 95% CI 1.9-5.7, p < 0.001), and BMI <26 (OR 1.9, 95% CI 1.1-3.3,p = 0.029) were predictive for the possibility of primary repair, and lateral meniscus injury presence decreased the likelihood of repair (OR 0.5, 95% CI 0.3-0.8, p = 0.008).

CONCLUSION

In this large cohort study, it was noted that 44% of patients had repairable ACL tears. Primary repair was more likely to be possible in older patients, patients with lower BMI and when surgery was performed within four weeks of injury.

The Stability study: a protocol for a multicenter randomized clinical trial comparing anterior cruciate ligament reconstruction with and without Lateral Extra-articular Tenodesis in individuals who are at high risk of graft failure

Background

The purpose of anterior cruciate ligament reconstruction (ACLR) is to restore stability to the knee. Persistent rotational laxity following ACLR has been correlated with poor outcome and graft failure. We hypothesize that anterolateral complex reconstruction by way of a Modified Lemaire Lateral Extra-articular Tenodesis (LET) in combination with single bundle ACLR would reduce the risk of persistent rotatory laxity in young individuals who are deemed as being at high risk of failure. We will conduct a pragmatic, multicenter, randomized clinical trial comparing standard single bundle hamstring ACLR with combined ACLR and LET.

Methods

Six-hundred patients (300 per group) aged 25 years or less with an ACL deficient knee that meet two of the following three criteria will be included: 1) Grade 2 pivot shift or greater; 2) Returning to high risk cutting or pivoting sports; 3) Generalized ligamentous laxity. Participants will be seen at 3-months, 6-months, 12-months and 24-months post-operatively. The primary outcome measure is graft failure requiring revision ACLR or symptomatic instability associated with a positive asymmetric pivot shift indicating persistent rotational laxity. Patients will complete secondary outcome measures at each follow-up visit including patient-reported outcome measures, functional and biomechanical testing, and magnetic resonance imaging.

Discussion

This protocol is the first adequately powered randomized clinical trial investigating the effects of augmenting ACLR with an LET in patients at high-risk of graft failure. The successful completion of this trial has the potential to change surgical practice and provide evidence for the role of the LET in ACLR.

Trial registration

The trial is registered at ClinicalTrials.gov: NCT02018354, 23-12-2013.

Effectiveness of Reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts

Background

The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and the quadrupled hamstrings tendon.

Hypothesis

Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament.

Study Design

Case control study; Level of evidence, 3.

Methods

Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 controls were assessed. Kinematic data were collected (50 Hz) with a 6-camera optoelectronic system while the subjects descended stairs and, immediately after, pivoted on their landing leg. The dependent variable examined was the tibial internal-external rotation during pivoting. All patients in both groups were also assessed clinically and with the use of a KT-1000 arthrometer to evaluate anterior tibial translation.

Results

The results demonstrated that reconstructions with either graft successfully restored anterior tibial translation. However, both anterior cruciate ligament reconstruction groups had significantly increased tibial rotation when compared with the controls, whereas no differences were found between the 2 reconstructed groups.

Conclusion

The 2 most frequently used autografts for anterior cruciate ligament reconstruction cannot restore tibial rotation to normal levels.

Clinical Relevance

New surgical techniques are needed that can better approximate the actual anatomy and function of the anterior cruciate ligament.

Single-tunnel anatomic double-bundle anterior cruciate ligament reconstruction has the same effectiveness as double femoral, double tibial tunnel: A prospective randomized study

PURPOSE

To investigate whether single femoral, single tibial tunnel anatomic double-bundle anterior cruciate ligament (ACL) reconstruction is equal to or superior to double femoral, double tibial tunnel ACL double-bundle anatomic reconstruction in terms of restoring the stability and functions of the knee joint.

METHODS

A prospective clinical study was performed to compare 30 cases of single-tunnel ACL double-bundle anatomic reconstruction to 28 cases of double-tunnel ACL double-bundle anatomic reconstruction, with average follow-up of 36 months. All graft tendons were hamstring tendon autografts. Tunnel placements in all the cases were made anatomically. Clinical results were collected after reconstruction. Graft appearance, meniscus status and cartilage state under arthroscopy were compared and analyzed.

RESULTS

Tunnel placements were in the anatomic positions in both groups. On the lateral pivot-shift test performed at 36 months postoperatively, there was no significant difference between groups. Clinical results such as International Knee Documentation Committee score, Tegner activity scale, and range of motion showed no significant differences between the groups. The mean thickness of anteromedial graft was reduced by 10.3% and that of the posterolateral graft was reduced by 11.1% from the original graft thickness evaluated by magnetic resonance imaging. No new meniscal tears were found either group; however, cartilage damage occurred in the double-tunnel group at 39.3%, and this rate was significantly higher than that in the single-tunnel group (10.0%).

CONCLUSION

Single femoral, single tibial tunnel anatomic double-bundle ACL reconstruction has the same effectiveness as the double femoral, double tibial tunnel in restoring the knee's stability and functions.

Graft failure is more frequent after hamstring than patellar tendon autograft

PURPOSE

The risk of graft failure after anterior cruciate ligament (ACL) reconstructions with hamstring or patellar tendon was evaluated in a French population of athletes.

METHODS

Athletes who had undergone ACL autograft reconstruction and who received rehabilitation care at the European Center for Sports Rehabilitation (CERS; Capbreton, France) were screened for this prospective cohort study. Eligibility criteria included a simple hamstring autograft or patellar tendon autograft surgical technique. Patients were contacted by phone to participate in follow-up during the second year after surgery. The primary endpoint was the graft failure frequency, evaluated with a multivariate logistic model with adjustment for baseline patient characteristics. The secondary endpoint was time to graft failure, analyzed by an adjusted Cox model.

RESULTS

A total of 2424 athletes were included after having a hamstring autograft (semitendinosus and gracilis) or a patellar tendon autograft between 2011 and 2014. Of the 988 athletes who responded to a follow-up phone call (40.7% response rate), 33 were excluded for new contralateral ACL rupture (3.3%), with 955 included for analysis (713 hamstring autografts; 242 patellar-tendon autografts). There were no significant differences between the baseline characteristics of the patients analyzed and the population which did not respond to the questionnaire. A significant difference in the frequency of graft failure was seen, 6.5% for hamstring autografts vs 2.1% for patellar-tendon autografts [adjusted odds ratio (OR) = 3.64, 95% CI (1.55; 10.67); p = 0.007]. Mean time to graft failure was 10.7 vs 17.4 months for hamstring and patellar-tendon autografts respectively [adjusted hazard ratio (HR) = 3.50, 95% CI (1.53; 10.11); p = 0.008]. Age less than 25 years significantly increased the frequency of graft failure [adjusted OR = 3.85 (1.89; 8.72); p < 0.001]. The rate of patients returning to competitive sport after the first graft was not significantly different for the two techniques: 70.8% for hamstring and 77.8% for patellar tendon [adjusted OR = 0.718; 95% CI (0.50; 1.02)].

CONCLUSIONS

Graft failure is significantly more frequent after hamstring than patellar tendon autografts in a French population, despite similar rates of return to competition. Athletes aged less than 25 years have a higher risk of failure than those aged ≥ 25 years. Our results are in accordance with recent Scandinavian studies.

LEVEL OF EVIDENCE

II.

Individualized Anterior Cruciate Ligament Graft Matching: In Vivo Comparison of Cross-sectional Areas of Hamstring, Patellar, and Quadriceps Tendon Grafts and ACL Insertion Area

BACKGROUND

Recent literature correlated anterior cruciate ligament (ACL) reconstruction failure to smaller diameter of the harvested hamstring (HS) autograft. However, this approach may be a simplification, as relation of graft size to native ACL size is not typically assessed and oversized grafts may impart their own complications.

PURPOSE

To evaluate in vivo data to determine if the commonly used autografts reliably restore native ACL size.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Intraoperative data of the tibial insertion area and HS graft diameter were collected and retrospectively evaluated for 46 patients who underwent ACL reconstruction with HS autografts. Magnetic resonance imaging measurements of the cross-sectional area (CSA) of the possible patellar tendon (PT) and quadriceps tendon (QT) autografts were also done for each patient. The percentages of tibial insertion site area restored by the 3 possible grafts were then calculated and compared for each individual.

RESULTS

The mean ACL tibial insertion area was 107.2 mm² (60.5-155.5 mm²). The mean CSAs of PT, HS, and QT were 33.2, 55.3, and 71.4 mm², respectively. When all grafts were evaluated, the percentage reconstruction of the insertion area varied from 16.2% to 123.1% on the tibial site and from 25.5% to 176.7% on the femoral site, differing significantly for each graft type ( P < .05). On average, 32.8% of the tibial insertion area would have been filled with PT, 53.6% by HS, and 69.5% by QT. Based on previous cadaveric studies indicating that graft size goal should be 50.2% ± 15% of the tibial insertion area, 82.7% of patients in the HS group were within this range (36.9%, QT; 30.5%, PT), while 65.2% in the PT group were below it and 60.9% in the QT group were above it.

CONCLUSION

ACL insertion size and the CSAs of 3 commonly used grafts vary greatly for each patient and are not correlated with one another. Thus, if the reconstructed ACL size is determined by the harvested autograft size alone, native ACL size may not be adequately restored. PT grafts tended to undersize the native ACL, while QT might oversize it.

CLINICAL RELEVANCE

These results may help surgeons in preoperative planning, as magnetic resonance imaging measurements can be helpful in determining individualized graft choice to adequately restore the native ACL.

Biomechanical assessment of an alternative method of staple fixation for anchoring the Bone Patellar Tendon Bone graft to the tibia

INTRODUCTION

The Anterior cruciate ligament (ACL) is the most commonly injured ligament around the knee and is best reconstructed with a biological graft. For ideal graft fixation, there should be sufficient initial strength to avoid failure of fixation and sufficient stiffness to restore the stability of the knee and to avoid gradual loosening in the post-operative period.When considering fixation of Bone Patellar Tendon Bone (BPTB) grafts to the tibia, the interference screw is considered to be the gold standard. As an alternative, we have used of staples and stainless steel (SS) wire to anchor the BPTB graft to the tibia and femur. The aim of this study was to assess the biomechanical efficacy of this fixation technique for anchoring the BPTB graft to the proximal tibia. We used a bovine model to compare three fixation techniques -interference screw, braided polyester sutures tied to a screw post and SS wire tied to a staple.

MATERIALS AND METHODS

Fifteen fresh bovine knees specimens were used for the study. The patella was fixed to a load cell and the construct was pre-tensioned to 40N to allow for creep of the tendon. The BPTB graft was fixed to the tibia using the three fixation techniques - the interference screw, polyester suture tied to a post, and SS wire anchored to a staple. After fixation, the graft was subjected to a single load to failure test, and the forces generated were recorded. The ultimate failure load (the pullout strength), stiffness, and mode of failure were noted.

RESULTS

In the single load-to-failure biomechanical testing, the ultimate failure load and stiffness for Staple with SS wire were 726.40N and 61.9N/mm respectively. For the screw post and polyester suture, it was 733.20N and 53.22N/mm, and for Interference screw - 594.00N and 79.50 N/mm respectively. There was no statistically significant difference in the stiffness or ultimate failure load between the three fixation techniques. The graft fixation using interference screws failed at the bone- tunnel interface by slippage of the bone block from the tunnel in all 5 specimens. In all 5 of the specimens fixed with polyester suture and the screw post, the fixation failed when the polyester suture snapped. When the SS wire and staple construct was stressed, the graft failed as the SS wire cut through the graft in 4 specimens, and in the fifth construct, the knot over the staple unraveled as the load was applied.

CONCLUSION

The biomechanical properties of BPTB graft fixation with SS wire tied to a staple is similar to that of other fixation devices like the interference screw and suture post. This technique provides a simple, yet effective fixation for the graft - but needs further clinical assessment.

Increased bone tracer uptake in symptomatic patients with ACL graft insufficiency: a correlation of MRI and SPECT/CT findings

PURPOSE

Magnetic resonance imaging (MRI) and single-photon emission computerised tomography/computerised tomography (SPECT/CT) are used as diagnostic tools in symptomatic patients after reconstruction of the anterior cruciate ligament (ACL). The benefit of SPECT/CT in comparison with MRI is under debate. The purpose of this study was to investigate whether and how bone tracer uptake (BTU) intensity and distribution in SPECT/CT correlate with MRI findings in symptomatic patients after ACL reconstruction.

METHODS

Twenty-nine patients (male:female = 22:7, mean age ± SD 26 ± 10 years) with symptoms of pain and instability after ACL reconstruction were retrospectively investigated using prospectively acquired SPECT/CT and MRI. On MRI graft tear, graft signal intensity, bone marrow oedema, tunnel cyst formation, roof impingement, roof osteophytes, local arthrofibrosis, joint effusion and synovial thickness were analysed by two readers blinded to the BTU results. BTU was anatomically localised and volumetrically quantified. Spearman's rho test was used for correlation of BTU in SPECT/CT and MRI findings (p < 0.05).

RESULTS

SPECT/CT showed increased femoral and tibial BTU in patients with MRI-confirmed graft tear, signal hyperintensity of the intraarticular graft section, joint effusion, synovial thickening, roof osteophytes and bone marrow oedema. Cyst formation in the femoral tunnel results in significantly reduced BTU in femur and tibia. No correlation of increased BTU was found for graft impingement and graft arthrofibrosis.

CONCLUSIONS

Bone tracer uptake in SPECT/CT and defined MRI findings in symptomatic patients after ACL reconstruction were correlated. Both imaging modalities have a definite role in post-operative diagnostic and have established their value in those patients. This study provides a better understanding of the clinical value of SPECT/CT versus MRI in the clinical decision-making process. SPECT/CT provides a window into the in vivo loading of the joint as well as bone remodelling and graft incorporation process. In addition, ACL graft insufficiency can be detected by increased BTU.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

ACL Graft and Contralateral ACL Tear Risk within Ten Years Following Reconstruction: A Systematic Review

BACKGROUND

Anterior cruciate ligament (ACL) graft tear and contralateral ACL injury have devastating effects on patient outcomes following ACL reconstruction. Long-term results after ACL reconstruction are being reported with greater frequency, allowing a detailed analysis of the long-term risk of failure.

METHODS

A systematic review of prospective studies that recorded the risk of ACL graft rupture and contralateral ACL injury following primary ACL reconstruction was performed. All studies included intra-articular ACL reconstruction with modern techniques and patellar tendon or hamstring autograft with a minimum follow-up of ten years.

RESULTS

Nine studies met the inclusion and exclusion criteria. The overall ACL graft rupture risk was 7.9% (211 ruptures in 2682 reconstructions) and ranged from 3.2% to 11.1% in the individual studies. The overall risk of ACL injury in the contralateral limb was 12.5% (335 injuries in 2682 reconstructions) and ranged from 0.6% to 22.7% in the individual studies. Among the seven homogeneous studies that were pooled, the overall risk of a contralateral ACL tear was 1.63 (95% confidence interval [CI]: 1.30 to 2.04) times that of a graft tear during the follow-up period.

CONCLUSIONS

At a minimum follow-up time of ten years, the risk of contralateral ACL tear significantly exceeds the risk of ACL graft rupture. Further work is necessary to understand and potentially reduce this risk of graft and contralateral ACL tears.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Short-term complications in intra- and extra-articular anterior cruciate ligament reconstruction. Comparison with the literature on isolated intra-articular reconstruction. A multicenter study by the French Arthroscopy Society

INTRODUCTION

Lateral tenodesis (LT) is performed to limit the risk of iterative tear following anterior cruciate ligament (ACL) reconstruction in at-risk patients. By adding an extra procedure to isolated ACL graft, LT reconstruction increases operating time and may complicate postoperative course. The objective of the present study was to evaluate the rate of early complications. The study hypothesis was that associating ALL reconstruction to ACL reconstruction does not increase the complications rate found with isolated ACL reconstruction.

MATERIAL AND METHODS

A prospective multicenter study included 392 patients: 70% male; mean age, 29.9 years; treated by associated ACL and LT reconstruction. All adverse events were inventoried.

RESULTS

Mean hospital stay was 2 days, with 46% day-surgery. Walking was resumed at a mean 27 days, with an advantage for patients treated by the hamstring technique. The early postoperative complications rate was 12%, with 1.7% specifically implicating LT reconstruction: pain, hematoma, stiffness in flexion and extension, and infection. There was a 5% rate of surgical revision during the first year, predominantly comprising arthrolysis for extension deficit. The 1-year recurrence rate was 2.8%.

DISCUSSION

The complications rate for combined intra- and extra-articular reconstruction was no higher than for isolated intra-articular ACL reconstruction, with no increase in infection or stiffness rates. The rate of complications specific to ALL reconstruction was low, at 1.7%, and mainly involved fixation error causing lateral soft-tissue impingement.

LEVEL OF EVIDENCE

IV, prospective multicenter study.

Bone-Patellar Tendon-Bone Versus Hamstring Tendon Autografts for Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review of Overlapping Meta-analyses

BACKGROUND

Previous meta-analyses have compared bone-patellar tendon-bone (BPTB) with hamstring tendon (HT) autografts for primary anterior cruciate ligament reconstruction (ACLR).

PURPOSE

To conduct a systematic review of overlapping meta-analyses comparing BPTB with HT autografts for ACLR to determine which meta-analyses provide the best available evidence.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review was performed by searching the PubMed and Cochrane Library databases. Search words included "anterior cruciate ligament" AND "patellar tendon" AND "hamstring tendon" AND "meta-analysis." Results were reviewed to determine study eligibility. Patient outcomes and postoperative complications were extracted from the included meta-analyses. Meta-analysis quality was assessed using the Oxman-Guyatt and Quality of Reporting of Meta-analyses (QUOROM) scores. The Jadad decision algorithm was then utilized to determine which meta-analyses provided the best level of evidence.

RESULTS

Sixteen meta-analyses containing an average of 1396 patients met the eligibility criteria. Most studies found BPTB autografts to provide superior stability but more postoperative complications, such as anterior knee pain and kneeling pain. Studies by Gabler et al (2016), Mohtadi et al (2011), and Xie et al (2015) received the highest Oxman-Guyatt and QUOROM scores, and therefore, these meta-analyses proved to provide the highest level of evidence. Additionally, Xie et al was selected as the highest-quality study in this systematic review based on the Jadad decision algorithm.

CONCLUSION

The current best evidence suggests that ACLR with BPTB autografts provides superior static knee stability and that there are fewer postoperative complications in ACLR with HT autografts.

Comparison of patellar versus hamstring tendon autografts in arthroscopic anterior cruciate ligament reconstruction: A 6-month follow-up of a randomized clinical trial

Background:

The purpose of this study was to compare the outcomes of anterior cruciate ligament (ACL) reconstruction using the patellar versus hamstring tendon (HT) autograft.

Materials and Methods:

In this randomized clinical trial, fifty patients undergoing arthroscopic ACL reconstruction were randomized into two equal groups: Those treated with either autogenous patellar tendon grafts (PT group) or HT group grafts. All patients were reviewed immediately after surgery, at 6 and 12 weeks after surgery, and then at 6 months using the International Knee Documentation Committee evaluation form. Infection, severity of pain (visual analog scale), duration of rehabilitation, and clinical and magnetic resonance imaging (MRI) findings were assessed at the 6-month follow-up. Positive pivot shift and Lachman test were considered clinical signs and symptoms of treatment failure. In addition, the absence of the ACL or transverse ACL rather than the posterior oblique ligament is an MRI finding that indicates treatment failure.

Results:

Comparing changes in pain and range of motion (ROM) in patients first and 6 months after therapy show that pain had been relief significantly (P < 0.001) and ROM dramatically changes (P < 0.001). The average rehabilitation period in the PT group was 13.2 ± 2.08 weeks whereas in the HT group, it was 9.28 ± 2.26 weeks. A significant difference was seen between the two groups in terms of the rehabilitation period (P < 0.001). No significant difference was found in the normal ROM between the groups (P = 0.32). When the pain severity was considered, a significant difference was found between the PT group and the HT group (P < 0.001). The HT group patients had less knee pain than did the PT group patients. No significant difference in infection rates was seen between two groups (P = 0.66).

Conclusion:

Considering the better outcomes of HT reconstructions for the two parameters of pain severity and rehabilitation period, we consider HTs to be the ideal graft choice for ACL reconstructions.

Editorial Commentary: Size Does Matter-Anterior Cruciate Ligament Graft Diameter Affects Biomechanical and Clinical Outcomes

Anterior cruciate ligament (ACL) graft strength is related to graft diameter and how ACL grafts heal. All grafts appear to lose strength during healing. Clinical studies have documented that hamstring grafts less than 8 mm wide are more vulnerable to failure. Tripling the semitendinosus allows to increase the graft diameter and strength. A recent study documents a semitendinosus tripling technique with excellent clinical results.

Primary anterior cruciate ligament reconstruction: perioperative considerations and complications

Anterior cruciate ligament (ACL) injuries are among the most commonly studied orthopaedic injuries. Despite having an excellent prognosis, complications do occur. The timely recognition and management of complications is imperative to ensure the success of reconstruction. Avoiding such complications requires thorough preoperative planning, proficient technical skills to properly manage intraoperative complications, and an extensive knowledge of possible postoperative complications.

Anatomic Anterior Cruciate Ligament Reconstruction via Independent Tunnel Drilling: A Systematic Review of Randomized Controlled Trials Comparing Patellar Tendon and Hamstring Autografts

PURPOSE

To collect the highest level of evidence comparing anatomic anterior cruciate ligament (ACL) reconstruction via independent tunnel drilling using bone-patellar tendon-bone (BTB) and hamstring tendon (HT) autografts in terms of clinical outcome and failure rate.

METHODS

We performed a systematic review of clinical trials that randomized patients to ACL reconstruction with either BTB or HT autografts with a minimum 2-year follow-up. Only trials using independent tunnel drilling, including outside-in and anteromedial portal techniques, for both autografts were eligible for inclusion, whereas all transtibial studies were excluded. Study design, demographics, surgical technique, rehabilitation protocol, and clinical outcomes were compiled. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Quality assessment was performed using the Coleman Methodological Scale (CMS).

RESULTS

Six published studies reporting on 5 randomized controlled trials (RCTs) met the inclusion criteria. No study reported a difference in rerupture rate between BTB and HT. BTB-reconstructed knees experienced a greater incidence of anterior knee pain or crepitus in 2/7 trials and radiographic evidence of degenerative change in 3/7 trials. HT-reconstructed knees had increased instrumented laxity in 2/7 trials and less knee flexion strength postoperatively.

CONCLUSIONS

This study collects all available Level I and II evidence for anatomic ACL reconstruction using BTB and HT grafts. According to the data presented in these studies, clinical outcome scores and failure rates showed no differences for anatomic reconstruction using either autograft. However, in some studies, BTB-reconstructed knees experienced a greater incidence of anterior knee pain and radiographic evidence of degenerative change, and in others, HT-reconstructed knees had increased laxity and less knee flexion strength. In our opinion, both BTB and HT autografts remain valid options for ACL reconstruction when using anatomic drilling techniques, providing a stable knee with reliable return to activity.

LEVEL OF EVIDENCE

Level II, systematic review of Level I and II studies.

Credibility and quality of meta-analyses addressing graft choice in anterior cruciate ligament reconstruction: a systematic review

PURPOSE

This systematic review examined the methodological credibility and quality of reporting of all meta-analyses which have compared bone-patellar tendon-bone (BPTB) versus hamstring tendon (HT) for anterior cruciate ligament (ACL) reconstruction (ACLR).

METHODS

EMBASE, MEDLINE, and The Cochrane Library were systematically searched, and two reviewers independently assessed eligibility, credibility according to the Users' Guide to medical literature, and completeness of reporting according to the preferred reporting items for systematic review and meta-analyses (PRISMA) checklist. Inter-rater agreement was quantified using Kappa, and we used Pearson's correlation coefficient to evaluate potential associations.

RESULTS

Seventeen meta-analyses were identified comparing BPTB versus HT for ACLR. The majority of meta-analyses were published in 2011 (5; 29 %), and North America was the most common continent of publication (6; 35 %). The three most commonly reported outcomes were stability (82 %), complications (76 %), and function (return to sport, IKDC score) (71 %). The median number of satisfactorily reported items in the Users' Guide was three out of seven (IQR 2-4). The median number of satisfactorily reported items in PRISMA for the meta-analyses was 20 out of 27 (IQR 19-22).

CONCLUSION

The credibility of the meta-analyses comparing BPTB versus HT autograft for ACLR although limited is improving with time. Earlier studies had limited methodological rigour; however, the more recent studies have shown promise in improved methodology. The study findings suggest that decisions should be made on a case-to-case basis with coordination of patient factors and preferences as well as surgeon experience on the background of the best available evidence.

LEVEL OF EVIDENCE

IV.

Quantitative assessment of patellar vascularity following bone-patellar tendon-bone autograft harvest for ACL reconstruction

PURPOSE

Recent anatomic studies have suggested that the dominant arterial supply of the patella enters through the inferior pole. Based upon these findings, we hypothesized that bone-patellar tendon-bone graft harvest can significantly diminish patellar vascularity.

METHODS

Nine matched pair cadaveric knee specimens (mean age 47.4 years) were dissected and cannulated. A single knee was selected to undergo routine graft harvest, and the contralateral knee was left intact to serve as a control. Gadolinium was injected, and magnetic resonance imaging (MRI) signal enhancement was quantified to determine differences in uptake. Each matched pair was subsequently injected with a urethane polymer compound and dissected to correlate vessel disruption with MRI findings.

RESULTS

We identified two predominating patterns of vessel entry. In one pattern, the vessel entered the inferomedial aspect (five o'clock/right, seven o'clock/left) of the patella and was disrupted by graft harvest in 2/9 (22.2 %) pairs. In the second pattern, the vessel entered further medial (four o'clock/right, eight o'clock/left) and was not disrupted (7/9, 78.8 %). The mean decrease in gadolinium uptake following disruption of the predominant vessel measured 56.2 % (range 42.6-69.5 %) compared to an average decrease of 18.3 % (range 7.1-29.1 %) when the dominant arterial supply to the inferior pole remained intact (p < 0.04).

CONCLUSION

Medial entry of the predominant vessel precluded vessel disruption. Disruption of the dominant arterial supply can result in a significant decrease in patellar vascularity. Modification of graft harvest techniques and areas of surgical dissection should be explored to minimize vascular insult. Further correlation with clinical studies/outcomes is necessary to determine a potential association between vascular insult and anterior knee pain.

Does Anteromedial Portal Drilling Improve Footprint Placement in Anterior Cruciate Ligament Reconstruction?

BACKGROUND

Considerable debate remains over which anterior cruciate ligament (ACL) reconstruction technique can best restore knee stability. Traditionally, femoral tunnel drilling has been done through a previously drilled tibial tunnel; however, potential nonanatomic tunnel placement can produce a vertical graft, which although it would restore sagittal stability, it would not control rotational stability. To address this, some suggest that the femoral tunnel be created independently of the tibial tunnel through the use of an anteromedial (AM) portal, but whether this results in a more anatomic footprint or in stability comparable to that of the intact contralateral knee still remains controversial.

QUESTIONS/PURPOSES

(1) Does the AM technique achieve footprints closer to anatomic than the transtibial (TT) technique? (2) Does the AM technique result in stability equivalent to that of the intact contralateral knee? (3) Are there differences in patient-reported outcomes between the two techniques?

METHODS

Twenty male patients who underwent a bone-patellar tendon-bone autograft were recruited for this study, 10 in the TT group and 10 in the AM group. Patients in each group were randomly selected from four surgeons at our institution with both groups demonstrating similar demographics. The type of procedure chosen for each patient was based on the preferred technique of the surgeon. Some surgeons exclusively used the TT technique, whereas other surgeons specifically used the AM technique. Surgeons had no input on which patients were chosen to participate in this study. Mean postoperative time was 13 ± 2.8 and 15 ± 3.2 months for the TT and AM groups, respectively. Patients were identified retrospectively as having either the TT or AM Technique from our institutional database. At followup, clinical outcome scores were gathered as well as the footprint placement and knee stability assessed. To assess the footprint placement and knee stability, three-dimensional surface models of the femur, tibia, and ACL were created from MRI scans. The femoral and tibial footprints of the ACL reconstruction as compared with the intact contralateral ACL were determined. In addition, the AP displacement and rotational displacement of the femur were determined. Lastly, as a secondary measurement of stability, KT-1000 measurements were obtained at the followup visit. An a priori sample size calculation indicated that with 2n = 20 patients, we could detect a difference of 1 mm with 80% power at p < 0.05. A Welch two-sample t-test (p < 0.05) was performed to determine differences in the footprint measurements, AP displacement, rotational displacement, and KT-1000 measurements between the TT and AM groups. We further used the confidence interval approach with 90% confidence intervals on the pairwise mean group differences using a Games-Howell post hoc test to assess equivalence between the TT and AM groups for the previously mentioned measures.

RESULTS

The AM and TT techniques were the same in terms of footprint except in the distal-proximal location of the femur. The TT for the femoral footprint (DP%D) was 9% ± 6%, whereas the AM was -1% ± 13% (p = 0.04). The TT technique resulted in a more proximal footprint and therefore a more vertical graft compared with intact ACL. The AP displacement and rotation between groups were the same and clinical outcomes did not demonstrate a difference.

CONCLUSIONS

Although the AM portal drilling may place the femoral footprint in a more anatomic position, clinical stability and outcomes may be similar as long as attempts are made at creating an anatomic position of the graft.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Magnesium inference screw supports early graft incorporation with inhibition of graft degradation in anterior cruciate ligament reconstruction

Patients after anterior cruciate ligament (ACL) reconstruction surgery commonly encounters graft failure in the initial phase of rehabilitation. The inhibition of graft degradation is crucial for the successful reconstruction of the ACL. Here, we used biodegradable high-purity magnesium (HP Mg) screws in the rabbit model of ACL reconstruction with titanium (Ti) screws as a control and analyzed the graft degradation and screw corrosion using direct pull-out tests, microCT scanning, and histological and immunohistochemical staining. The most noteworthy finding was that tendon graft fixed by HP Mg screws exhibited biomechanical properties substantially superior to that by Ti screws and the relative area of collagen fiber at the tendon-bone interface was much larger in the Mg group, when severe graft degradation was identified in the histological analysis at 3 weeks. Semi-quantitative immunohistochemical results further elucidated that the MMP-13 expression significantly decreased surrounding HP Mg screws with relatively higher Collagen II expression. And HP Mg screws exhibited uniform corrosion behavior without displacement or loosening in the femoral tunnel. Therefore, our results demonstrated that Mg screw inhibited graft degradation and improved biomechanical properties of tendon graft during the early phase of graft healing and highlighted its potential in ACL reconstruction.

Comparison of Patellar Tendon and Hamstring Tendon Anterior Cruciate Ligament Reconstruction: A 15-Year Follow-up of a Randomized Controlled Trial

BACKGROUND

Numerous studies have compared patellar tendon (PT) and hamstring tendon (HS) anterior cruciate ligament (ACL) reconstructions in the short to midterm, but fewer long-term results have been published.

HYPOTHESIS

There will be no difference in functional outcome between ACL reconstruction performed with PT and HS grafts, but PT grafts will have more donor site morbidity.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Sixty-five patients undergoing ACL reconstruction were randomized to receive either a PT graft or a 4-strand HS graft. Early results were reported at 4, 8, 12, 24, and 36 months. Forty-seven patients (22 of 31 PT and 25 of 34 HS) were reviewed at a mean of 15.3 years.

RESULTS

Four graft ruptures (1 PT, 3 HS) and 6 contralateral ACL injuries (4 PT, 2 HS) occurred in the group that was reviewed. There was no statistically significant difference between the groups for any of the variables measured. There was a similar incidence of anterior knee pain and kneeling pain in both groups. The previously observed increased extension deficit in the PT group at 3 years was not present at 15 years, and there was no significant between-group difference in knee laxity. A higher proportion of patients in the PT group were participating in sport on a weekly basis (73% PT, 48% HS; P = .05). There was no difference in the degree of osteoarthritis between the groups.

CONCLUSION

This randomized controlled trial showed that HS and PT ACL reconstructions have comparable results at an average 15-year follow-up. Contrary to the study hypothesis, some of the graft differences seen at earlier review were not present at 15 years, and patients with PT grafts were more active in sport participation. Overall, both graft types provided good long-term subjective and objective outcomes.

Radiographic landmarks for surgical reconstruction of the anterolateral ligament of the knee

PURPOSE

To determine the radiographic landmarks of the anterolateral ligament (ALL) on the femur and tibia to assist in intraoperative graft placement during ALL reconstruction.

METHODS

The footprints of the ALL, fibular collateral ligament (FCL), popliteus insertion, lateral gastrocnemius insertion, and Gerdy's tubercle were isolated and centrally marked with tantalum beads in thirteen fresh-frozen cadaveric knees. Measurements were taken from the true lateral fluoroscopic images. On the femur, the mean distances from the ALL origin to the FCL origin and from the ALL origin to the popliteus insertion were measured. On the tibia, the mean distances from the ALL insertion to Gerdy's tubercle and from the ALL insertion to the lateral tibial plateau were measured. Furthermore, radiographic descriptions of the ALL origin and insertion were developed.

RESULTS

The ALL origin on the femur averaged 3.3 ± 1.5 mm anterior-distal to the FCL origin in one anatomical variant and 5.4 ± 1.4 mm posterior-proximal to the FCL origin in a second variant. The ALL origin was 9.9 ± 2.7 mm from the popliteus insertion. The ALL origin is described as overlying the posterior femoral cortical line, between Blumensaat's line and a line from the posterior condylar articular edge parallel to Blumensaat's line. The ALL insertion on the tibia averaged 24.7 ± 4.5 mm posterior to Gerdy's tubercle and 11.5 ± 2.9 mm distal to the lateral tibial plateau. The tibial ALL insertion is described between the posterior tibial cortical line and a parallel line drawn down from the apex of the tibial spine, and overlying a line drawn perpendicular to the posterior tibial cortical line starting from the apex of the posterior tibial condyles.

CONCLUSIONS

Using direct lateral fluoroscopy, radiographic landmarks of the ALL origin and insertion have been described.

Arthroscopic anatomical double bundle anterior cruciate ligament reconstruction: A prospective longitudinal study

BACKGROUND

Single bundle anterior cruciate ligament (ACL) reconstruction has been the current standard of treatment for ACL deficiency. However, a significant subset of patients continue to report residual symptoms of instability with a poor pivot control. Cadaveric biomechanical studies have shown double bundle (DB) ACL reconstructions to restore the knee kinematics better. This study evaluates the outcome of DB ACL reconstruction.

MATERIALS AND METHODS

30 consecutive patients who underwent anatomic DB ACL reconstruction were included in this prospective longitudinal study. There were all males with a mean age of 25 ± 7.45 years. All patients were prospectively evaluated using GeNouRoB (GNRB) arthrometer, functional knee scores (International Knee Documentation Committee [IKDC] and Lysholm) and postoperative magnetic resonance imaging (MRI) for comparing the graft orientation and footprint of the reconstructed ACL with that of the normal knee.

RESULTS

The average followup was 36.2 months. At the time of final followup the mean Lysholm score was 93.13 ± 3.31. As per the objective IKDC score, 26 patients (86.6%) were in Group A while 4 patients (13.3%) were in Group B. The mean differential anterior tibial translation by GNRB, arthrometer was 1.07 ± 0.8 mm (range 0.1-2.3 mm). All cases had a negative pivot shift test. MRI scans of operated and the contralateral normal knee showed the mean sagittal ACL tibial angle coronal ACL tibial angle and tibial ACL footprint to be in accordance with the values of the contralateral, normal knee.

CONCLUSION

The study demonstrates that DB ACL reconstruction restores the ACL anatomically in terms of size and angle of orientation. However, long term studies are needed to further substantiate its role in decreasing the incidence of early osteoarthritic changes compared to the conventional single bundle reconstructions.

Arthroscopic BPTB graft reconstruction in ACL ruptures: 15-year results and survival

PURPOSE

The aim of this study is to investigate the 15-year results and survival of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft.

METHODS

ACL BPTB reconstruction was performed in 250 consecutive patients. Of these patients, 88% returned for a follow-up examination at 15 years after reconstruction. Therefore, 220 patients were studied. Mean time from injury to intervention was 3.4months (range 2 to 16). The parameters for assessment of results were subjective satisfaction, clinical examination (pivot-shift test, Lachman test with KT-1000), recovery of pre-injury activity level, and long-leg standing radiographs. We also evaluated the presence of meniscal and/or chondral injuries during the procedure. Failure rates were also evaluated. We defined a failure as severe instability not compatible with the activities of daily living (ADL) due to graft rupture.

RESULTS

8.2% of patients required a revision procedure because of graft rupture. In subjective terms, 98.1% of patients said that they were satisfied with the surgical outcomes after 15 years. Pivot shift test was normal in 93.5% at 15 years. Lachman test (KT-1000) was normal in 95.4% at 15 years. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15 years.

CONCLUSIONS

The survival prevalence of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft at 15 years was 94.8%. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15 years.

LEVEL OF EVIDENCE

Level IV.

High satisfaction yet decreased activity 4 years after transphyseal ACL reconstruction

BACKGROUND

ACL injuries in preteens and teens are common occurrences. Reconstruction is believed to be optimum treatment for those wishing to return to running, cutting, and jumping sports. Rates of reoperation, satisfaction, and long-term return to and maintenance of preinjury activity after ACL reconstruction in young athletes are important information for physicians, patients, and parents.

QUESTIONS/PURPOSES

The purposes of this study were to address the following questions in this skeletally immature patient population undergoing ACL reconstruction: (1) What is the reinjury rate and the need for subsequent surgeries? (2) How do patient satisfaction and function as assessed by patient and physician correlate with return to sport? (3) What factors contribute to failure to return to preinjury activity levels?

METHODS

This is a retrospective review of 29 patients who underwent transphyseal ACL reconstruction using soft tissue grafts passed through open physes and followed to skeletal maturity, and at least 2 years from their index surgery, who were invited and returned for a study interview and examination. Pre- and postinjury activity levels were assessed via the Tegner activity score, satisfaction was determined using a 10-point Likert scale, function was assessed via the Lysholm score and IKDC grade, and an open-ended questionnaire was used for explanations of changes in activity levels. Reoperations were classified as major or minor, determined from a review of the medical records conducted after interview and examination.

RESULTS

At a minimum followup of 2 years (mean, 4 years; range, 2-8 years), four revision reconstructions and seven minor operations were performed for a reoperation rate of 11 of 29 (38%). Eight of 29 patients (28%) sustained contralateral ACL ruptures. The mean satisfaction score was 9 (range, 4-10) and mean Lysholm score was 91 (range, 61-100). Only 12 of 29 (41%) patients returned to and maintained their preinjury level of sport. High satisfaction correlated with return to prior level of sports, although there was no relationship between function and activity level. Reoperation on the index knee or contralateral ACL tear did not correlate with a change in activity level; rather, most patients who were less active indicated a change in interest with advancing age.

CONCLUSIONS

Despite high satisfaction and function, less than 50% of patients maintained their preinjury level of play 4 years after ACL reconstruction. Satisfaction correlated significantly with knee function; highly satisfied patients were more likely to return to and maintain their prior level of participation in sports. Contributing factors to decreased activity include changes in lifestyle with increasing age. Reoperation did not correlate with lower activity scores or failure to return to sports.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

ACL reconstruction with physiological graft tension by intraoperative adjustment of the anteroposterior translation to the uninjured contralateral knee

PURPOSE

Fixation of anterior cruciate ligament (ACL) substitutes with non-physiological anteroposterior translation (APT) worsens outcome. The aim was to present a technique for physiological APT adjustment of the transplant in ACL reconstruction and its outcome at midterm.

METHODS

In a consecutive series of 28 patients (age 32 ± 11 years, 24 male), chronic ACL deficiency was treated by bone-patella-tendon-bone reconstruction. Transplant APT was adjusted to that of the contralateral uninjured ACL, measured 3, 6, and 12 months postoperatively using the Rolimeter. At a median follow-up of 5.3 years (3-8 years), 82% of the patients were re-evaluated with APT measurement and using IKDC-, Tegner-, Lysholm-Scores, conventional radiographs and MRI.

RESULTS

No differences in APT (mean ± SD) between uninjured and reconstructed knees were observed after adjustment (6 ± 1 versus 6 ± 1 mm, n.s.). Three months postoperatively, a statistically significant increase in APT (7 ± 1 mm) and a further increase at midterm (9 ± 2 mm) were observed. Patients scored "normal" or "nearly normal", respectively, in 79% (IKDC) and 4 (3-9) points (Tegner; median, range) or 89 ± 9 points (Lysholm; mean ± SD). Radiological evaluation showed no, minimal or moderate joint degeneration in 5, 20 and 75% of patients, respectively. MRI confirmed intact ACL transplants in all patients.

CONCLUSION

ACL reconstruction using the presented technique was considered successful, as patients did not suffer from subjective instability, radiographic analysis did not provide evidence for graft rupture at midterm. However, APT increase and occurrence of degenerative changes in reconstructed knees at the midterm might not be prevented even by restoration of a physiological APT in ACL reconstruction. The Rolimeter can be used for quick and easy intraoperative indirect control of the applied tension to the ACL transplant by measuring the APT to obtain physiological tensioning resulting in a satisfying outcome at midterm.

LEVEL OF EVIDENCE

IV.

Anterior cruciate ligament reconstruction combined with valgus high tibial osteotomy allows return to sports

INTRODUCTION

This study reports a series of patients operated on by anterior cruciate ligament (ACL) reconstruction combined with valgus high tibial osteotomy (HTO) for chronic anterior knee instability associated with medial tibiofemoral osteoarthritis. It was hypothesized that the combined surgery would enable return to sport, stabilize the knee and relieve medial pain.

PATIENTS AND METHODS

A retrospective study enrolled a continuous series of 29 patients (20 males, nine females; mean age, 43 years (range, 25-56 yrs), at a mean 14 years (range, 2-29 yrs) after the initial injury. ACL autograft used a bone-patellar tendon-bone transplant in 12 patients and hamstring tendon transplant in 17. Medial opening wedge HTO used an asymmetric wedge plate. Results were assessed on subjective and objective IKDC scores, monopodal weight-bearing and full-leg radiographs, telemetry and Merchant view at a mean 6 years follow-up (range, 25 months to 12 years).

RESULTS

At follow-up, 23 patients had resumed sports activities, with 45% in competitive sports; 28 were free of instability and 21 free of pain. Mean subjective IKDC score was 77 (34-97) and 70% had A or B global objective IKDC scores. The knee axis was in 2.5° valgus.

DISCUSSION

Combined ACL graft and valgus HTO relieved pain in 70% of cases, and restored knee stability enabling return to sport in 80%.

LEVEL OF EVIDENCE

Level IV. Retrospective therapeutic study.

Biomechanical evaluation of the quadriceps tendon autograft for anterior cruciate ligament reconstruction: a cadaveric study

BACKGROUND

Recently, many surgeons have chosen the quadriceps tendon (QT) as an autograft for anterior cruciate ligament (ACL) reconstruction. However, there have not been biomechanical studies that quantitatively evaluated knee function after reconstruction using a QT autograft.

PURPOSE

To measure the 6 degrees of freedom knee kinematics and in situ graft forces after reconstruction with a QT autograft compared with a quadrupled semitendinosus and gracilis (QSTG) tendon autograft.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten human cadaveric knees (age, 54-64 years) were tested in 3 conditions: (1) intact, (2) ACL deficient, and (3) after ACL reconstruction using a QT or QSTG autograft. With use of a robotic/universal force-moment sensor testing system, knee kinematics and in situ forces in the ACL and autografts were obtained at 5 knee flexion angles under externally applied loads: (1) 134-N anterior tibial load, (2) 134-N anterior tibial load with 200-N axial compression, and (3) 10-N·m valgus and 5-N·m internal tibial torque.

RESULTS

Under the anterior tibial load, both autografts restored anterior tibial translation to within 2.5 mm of the intact knee and in situ forces to within 20 N of the intact ACL at 15°, 30°, and 60°. Adding compression did not change these findings. With the combined rotatory load, the anterior tibial translation and graft in situ forces were again not significantly different from the intact ACL. There were no significant differences between the grafts under any experimental condition.

CONCLUSION

Reconstruction of the ACL with a QT autograft restored knee function to similar levels as that reconstructed with a QSTG autograft under loads simulating clinical examinations.

CLINICAL RELEVANCE

The positive biomechanical results of this cadaveric study lend support to the use of a QT autograft for ACL reconstruction, as it could restore knee function immediately after surgery under applied loads that mimic clinical examinations.

Anatomic double-bundle anterior cruciate ligament reconstruction using in situ hamstring graft with 4 tunnels

A careful review of the literature suggests that a significant number of patients undergoing anterior cruciate ligament (ACL) reconstruction have less-than-optimal results. Although overall outcomes of ACL reconstruction are favorable, there remains considerable room for improvement. Anatomically, the ACL consists of 2 major functional bundles, the anteromedial bundle and the posterolateral bundle. Biomechanically, both bundles contribute significantly to the anterior and rotational stability of the knee. Therefore anatomic double-bundle ACL reconstruction techniques may further improve the outcomes in ACL surgery. This article presents a technique for arthroscopic double-bundle ACL reconstruction that includes the use of 2 femoral and 2 tibial tunnels to restore both the anteromedial and posterolateral bundles of the ACL with minimal hardware for fixation.

Gait analysis of anterior cruciate ligament reconstructed subjects with a combined tendon obtained from hamstring and peroneus longus

BACKGROUND

Stability of the knee joint is achieved by a complex process in which the anterior cruciate ligament (ACL) plays an important role. The rupture of this ligament is quite frequent especially in athletic young subjects. Various methods have been used to reconstruct the ACL. One of the new methods is to use a graft combined from peroneus longus and hamstring. As there is no evidence regarding this method, it was aimed to evaluate the efficiency of this method.

METHOD

Two groups of normal and those with ACL injury, in whom their ACLs were reconstructed with the new method, participated in this study. The kinematic and kinetic parameters during walking on level surface were evaluated by a motion analysis system (Qualysis) and a Kistler force plate. The difference between the parameters of operated and non-operated sides and also between patients and normal subjects was evaluated by use of a two sample t test (p-value was 0.05).

RESULTS

The results of this study showed that the pattern and magnitude of the loads transmitted by lower extrimity joints differed between normal and ACL reconstructed subjects. The sound side pattern and magnitude of motion were also influenced by ACL insufficiency.

CONCLUSIONS

The results of the current study showed that the reconstructed ACL by use of this method did not have enough performance to restore the function of the leg. As the knee joint is unstable following the use of this method, it is recommended to find a new method of ACL reconstruction to improve the function of this ligament after reconstruction.

Anterior cruciate ligament femoral socket drilling with a retrograde reamer: lessons from the learning curve

Whereas "anatomic" anterior cruciate ligament reconstruction may improve clinical results, the technique has introduced new technical challenges. The purpose of this technical note and video is to explore tips and tricks that improve femoral socket drilling with a retrograde reamer, bone-patellar tendon-bone graft passage, and interference screw fixation. The techniques for retrograde femoral socket drilling in an inside-out direction, bone-patellar tendon-bone graft passage, and interference screw fixation are described and demonstrated. Pitfalls, troubleshooting tips, and possible solutions are discussed. With the retrograde reamer, the femoral socket can be placed in the footprint of the anterior cruciate ligament with a longer and more vertical tunnel. By modifying the size of the patellar bone plug, graft passage is improved. With care and technique, interference screw fixation in the femoral socket over a guidewire is possible.

Anatomic double-bundle ACL reconstruction restricts knee extension in knees with hyperextension

PURPOSE

Double-bundle ACL reconstruction has been demonstrated to be at least as effective as single-bundle reconstruction in terms of restoring knee rotational and translational stability. Until now, the influence on knees with hyperextension has not been evaluated. It was the purpose of this study to evaluate whether double-bundle ACL reconstruction restricts extension in hyperextendable knees.

METHODS

Hamstring tendon reconstructions of 10 human cadaveric knees with the ability of hyperextension (age: 48 ± 14 years) were performed as single bundle (SB) on one side and double bundle (DB) on the other side. A surgical navigation system (BrainLab, Germany) was used to assess the kinematics of each knee at the intact and reconstructed state. A difference with regard to the anterior-to-posterior translation (AP) and rotational stability at 30° of knee flexion, 90° of flexion and the hyperextension capability of each specimen was analysed.

RESULTS

The difference in AP translation before and after the reconstruction was not significantly different in 30° and 90° of flexion (n.s). Both single- and double-bundle reconstructions restored the preoperative kinematics at 30° and 90° of knee flexion (n.s). The knee extension was 4° ± 1.8° with the intact ACL and 4° ± 1.7° after reconstruction in the SB group (n.s). The knee extension was 5° of hyperextension ± 1.1° with the intact ACL and 0° ± 0.4° after reconstruction in the DB group; the limitation of the extension was significantly larger in this group (p = 0.013).

CONCLUSION

Both single- and double-bundle ACL reconstruction techniques are capable of restoring knee anteroposterior and rotational stability. Double-bundle reconstructions significantly reduce knee extension in knees with hyperextension capability. Care must be taken when using double-bundle techniques in patients with knee hyperextension as this procedure may limit the knee extension after double-bundle ACL reconstruction.

Anterior-Posterior Instability of the Knee Following ACL Reconstruction with Bone-Patellar Tendon-Bone Ligament in Comparison with Four-Strand Hamstrings Autograft

Purpose. To evaluate anterior-posterior knee laxity using two different autografts. Material-Methods. 40 patients, (34 males and 6 women), 17-54 years old (mean: 31), were included in the present study. Group A (4SHS = 20) underwent reconstruction using four-strand hamstrings, and group B (BPBT = 20) underwent reconstruction using bone-patellar tendon-bone autograft. Using the KT-1000 arthrometer, knee instability was calculated in both knees of all patients preoperatively and 3, 6, and 12 months after surgery at the ACL-operated knee. The contralateral healthy knee was used as an internal control group. Results. Anterior-posterior instability using the KT1000 Arthrometer was found to be increased after ACL insufficiency. The recorded laxity improved after arthroscopic ACL reconstruction in both groups. However, statistically significant greater values were detected in the bone-patellar tendon-bone group, which revealed reduction of anteroposterior stability values to an extent, where no statistical significance with the normal values even after 3 months after surgery was observed. Conclusions. Anterior-Posterior instability of the knee improved significantly after arthroscopic ACL reconstruction. The bone-patellar tendon-bone graft provided an obvious greater stability.

Surgical and Biomechanical Perspectives on Osteoarthritis and the ACL Deficient Knee: A Critical Review of the Literature

This review was undertaken to better understand the debate regarding the issue of osteoarthritis associated with anterior cruciate ligament (ACL) injuries, from a surgical and biomechanical standpoint. Much of the current debate focuses on contributory surgical factors and their relative roles in increasing or decreasing the risk of future osteoarthritis development, primarily highlighting the controversy over whether reconstructive surgery itself is necessarily protective. This review addresses the evolution of ACL reconstruction techniques over time, and with a view to thoroughly examine the role of surgery, outcome differences in procedural technique are reviewed, with a focus on open versus arthroscopic methods, graft choice and the use of a double versus single bundle reconstruction technique. Moreover, other potentially important contributory factors are identified and discussed, such as intrinsic biomechanical alterations sustained at the time of initial injury, and how these may have a more significant role with regard to future osteoarthritic changes in the knee than previously attributed.