Clinical evaluation of arthroscopically assisted anterior cruciate ligament reconstruction: patellar tendon versus gracilis and semitendinosus autograft

Association of Anterior Knee Pain With Extension Deficit After Anterior Cruciate Ligament Reconstruction: A Systematic Review

Background

Previous systematic reviews have reported the incidence of anterior knee pain (AKP) and extension deficit (ED) after anterior cruciate ligament reconstruction (ACLR); however, both outcomes are estimated separately and thus are assumed to be uncorrelated.

Purpose

To estimate whether there is a clinically relevant association between the population effects of ED and AKP after ACLR.

Study Design

Systematic review; Level of evidence, 2.

Methods

Under PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was conducted by searching PubMed, EMBASE, and the Cochrane Library electronic databases for published articles reporting incidence of both AKP and ED after ACLR with either bone-patellar tendon-bone (BPTB) or hamstring (HS) graft that returned 298 studies after the initial search. A Bayesian hierarchical measurement error model estimated the population effect of ED and AKP.

Results

Twelve publications involving 976 patients (mean follow-up, 77.9 months; range, 24-180 months) were included in the systematic review. There was a clear, moderate correlation between population ED and population AKP for the BPTB (r = 0.40; 95% CI, 0.39-0.42) and the HS grafts (r = 0.35; 95% CI, 0.33-0.36). Model expected estimates for the population effects of AKP and ED were 24.1% (95% CI, 17.4%-31.9%) and 17.5% (95% CI, 10.6%-25.0%), respectively, for the BPTB graft and 16.1% (95% CI, 9.2%-23.9%) and 13.1% ED (95% CI, 6.0%-20.8%) for the HS graft, respectively. The posterior mean difference in AKP between BPTB and HS grafts was clear and substantial (8.3% [95% CI, 0.3% to 16.1%]); there was no substantial difference in the posterior mean difference of ED between BPTB and HS grafts (4.3% [95% CI, -3.8% to 13.0%).

Conclusion

Our systematic review demonstrated a moderate but clear correlation between ED and AKP irrespective of graft type. From a clinical perspective, this association emphasizes the need for intraoperative achievement of full extension and avoidance of situations that may cause ED. The higher incidence of AKP in patients with BPTB graft may also be attributed to factors related to the graft harvest site. Future metaregression analyses could investigate whether additional factors such as follow-up duration or rehabilitation protocols can moderate the association between AKP and ED after ACLR with either BPTB or HS graft.

Following Anterior Cruciate Ligament Reconstruction With Bone-Patellar Tendon-Bone Autograft, the Incidence of Anterior Knee Pain Ranges From 5.4% to 48.4% and the Incidence of Kneeling Pain Ranges From 4.0% to 75.6%: A Systematic Review of Level I Studies

Purpose

To (1) perform a systematic review of level I randomized controlled trials (RCTs) detailing the incidence of anterior knee pain and kneeling pain following anterior cruciate ligament reconstruction (ACLR) with bone-patellar tendon-bone (BPTB) autograft and (2) investigate the effect of bone grafting the patellar harvest site on anterior knee and kneeling pain.

Methods

A systematic review of level I studies from 1980 to 2023 was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome evaluated was the presence of donor site morbidity in the form of anterior knee pain or kneeling pain. A secondary subanalysis was performed to assess for differences in the incidence of postoperative pain between patient groups undergoing ACLR with BPTB receiving harvest site bone grafting and those in whom the defect was left untreated.

Results

Following full-text review, 15 studies reporting on a total of 696 patients met final inclusion criteria. Patients were followed for an average of 4.78 years (range, 2.0-15.3), and the mean age ranged from 21.7 to 38 years old. The incidence of anterior knee pain, calculated from 354 patients across 10 studies, ranged from 5.4% to 48.4%. The incidence of postoperative pain with kneeling was determined to range from 4.0% to 75.6% in 490 patients from 9 studies. Patients treated with bone grafting of the BPTB harvest site had no significant difference in incidence of any knee pain compared with those who were not grafted, with incidences of 43.3% and 40.2%, respectively.

Conclusions

Based on the current level I RCT data, the incidences of anterior knee pain and kneeling pain following ACLR with BPTB autograft range from 5.4% to 48.4% and 4.0% to 75.6%, respectively.

Level of Evidence

Level I, systematic review of RCTs.

Stand-Alone Tibial Interference Screw Fixation and Tibial Interference Screw Plus Tibial Staple Fixation Produce Comparable Outcomes After Primary Anterior Cruciate Ligament Reconstruction Using Hamstring Autografts

Purpose

To investigate the impact of adding a metal staple alongside the interference screw in tibial side graft fixation during anterior cruciate ligament reconstruction (ACLR).

Methods

All patients treated with autograft hamstring ACLR at our institution between January 2017 and December 2021 with a minimum 1-year follow-up were reviewed retrospectively. Patients treated with a stand-alone interference screw for tibial side fixation were compared with those treated with a combination of interference screw and staple. The primary outcome was failure of the reconstructed graft. Secondary outcomes were operative time, complication rate, and reoperation rate.

Results

A total of 497 patients met the study's inclusion and exclusion criteria. A combination of staple and interference screw was used in 167 patients (33.6%), whereas a standalone interference screw was used in 330 patients. There was no significant difference between the 2 groups in terms of operative time, complication rate, or failure rate. The mean follow-up was 23.25 (±13.29) months.

Conclusions

Our results demonstrate that augmenting the interference screw with a staple for tibial-side fixation in ACLR does not have a significant impact on operative time, reoperation rate, complications, or failure rates.

Level of Evidence

Level III, retrospective cohort study.

Persistent knee extension deficits are common after anterior cruciate ligament reconstruction: a systematic review and meta-analysis of randomised controlled trials

PURPOSE

Knee extension deficits complicate recovery from ACL injury and reconstruction; however, the incidence of knee extension loss is not well defined. The aim of this review was to identify the incidence of loss of extension (LOE) following ACL rupture and reconstruction, explore the definitions of knee extension deficits reported and identify prognostic factors affecting LOE incidence.

METHODS

A systematic search was conducted in Medline, Cochrane Library and PEDro for studies in publication up to November 2021, with no restrictions on publication year. References were screened and assessed for inclusion using predetermined eligibility criteria. Randomised controlled trials (RCTs) that quantified knee angle, loss of extension or incidence of extension deficit were included for quality assessment and data extraction. Statistical summaries were generated and meta-analyses performed in two parts to examine: (i) the probability of a datapoint being zero incidence compared to a nonzero incidence and (ii) the relationship between the predictors and nonzero LOE incidence.

RESULTS

A sample of 15,494 studies were retrieved using the search criteria, with 53 studies meeting eligibility criteria. The pooled results from 4991 participants were included for analysis, with 4891 participants who had undergone ACLR. The proportion of included studies judged at an overall low risk of bias was small (7.8%). The observed group and study were the most important predictors for whether a datapoint reported an incidence of extension deficit. Time to follow-up (P < 0.001) and graft type (P = 0.02) were found to have a significant influence on nonzero LOE incidence (%). Covariate adjusted estimates of average LOE indicated 1 in 3 patients presenting with LOE at 12 month follow-up, reducing to 1 in 4 at 2 years.

CONCLUSIONS

This review examined the definitions for the measurement and interpretation of postoperative knee extension and established the trajectory of knee extension deficit after ACL injury and reconstruction. While factors associated with loss of extension were identified, the exact trajectory of knee extension deficits was difficult to infer due to discrepancies in measurement techniques and patient variation. On average, 1 in 3 patients may present with loss of extension of at least 3 degrees at 12-month follow-up, decreasing to 1 in 4 at 2 years. These results may be used by clinicians as an upper threshold for acceptable complication rates following ACLR. Future work should focus on LOE as a clinically relevant complication of ACL injury and treatment with appropriate attention to standardisation of definitions, measurements and better understanding of natural history.

PROSPERO REGISTRATION NUMBER

CRD42018092295.

LEVEL OF EVIDENCE

Level I.

Bone-patellar tendon-bone versus two- and four-strand hamstring tendon autografts for ACL reconstruction in young adults: a Bayesian network meta-analysis

Bone-patellar tendon-bone (BPTB), two- and four-strand hamstring tendon (4SHT and 2SHT, respectively) are the most common autografts used for anterior cruciate ligament (ACL) reconstruction. The present study compared BPTB, 2SHT, and 4SHT for ACL reconstruction in terms of joint laxity, patient reported outcome measures (PROMs), rate of failure and anterior knee pain (AKP). The time to return to sport and the peak torque between the autografts were also compared. Finally, prognostic factors leading to worse outcomes were also investigated. It was hypothesized that all grafts yield similar proprieties in terms of joint laxity, patient reported outcome measures (PROMs) and rate of failure, but that the BPTB autograft causes a greater rate of anterior knee pain (AKP). The literature search was conducted. All clinical trials comparing BTPB and/or 2SHT, and/or 4SHT were accessed. Grafts other than BTPB and/or 4SHT and/or 2SHT were not considered. Articles reporting outcomes of allografts or synthetic grafts were not eligible, nor were those concerning revision settings. Articles reporting ACL reconstruction in patients with multi-ligament damage were also not eligible. Data from 95,575 procedures were retrieved. The median length of follow-up was 36 months. The median age of the patients was 27.5 years. With regard to joint laxity, similarity was found in terms of Lachman and Pivot shift tests between all three autografts. The BPTB demonstrated the greatest stability in terms of instrumental laxity. BPTB demonstrated the greatest PROMs. BPTB demonstrated the greatest rate of AKP, while AKP in 2SHT and 4SHT was similar. Concerning failure, statistically significant inconsistency was found (P = 0.008). The 4SHT demonstrated the quickest return to sport, followed by BPTB, and 2SHT. There was evidence of a negative association between the time span between injury to surgery, Lysholm score (P = 0.04), and Tegner scale (P = 0.04). Furthermore, there was evidence of a weak positive association between the time span between injury to surgery and return to sport (P = 0.01). BPTB may result in lower joint laxity, greater PROMs, and greater peak flexion torque compared to 2SHT and 4SHT autografts. On the other hand, BPTB reported the lowest peak extension torque and the greatest rate of AKP. Finally, a longer time span between injury and surgery negatively influences outcome.

Does an Adjustable-Loop Device Loosen following ACL Reconstruction with a Hamstring Graft? A Retrospective Study with a Follow-Up of Two Years

Arthroscopic anatomic anterior cruciate ligament reconstruction (ACLR) is the gold standard treatment for an ACL tear and requires the use of fixed or adjustable-loop devices to fix a femoral-side graft. Although the adjustable mechanism is designed to provide one-way tensioning, there is a concern that the adjustable loop will loosen and lengthen during cyclic loads, creating graft laxity. The present paper is a retrospective study of patients who underwent ACLR with the fixation of a hamstring graft with an adjustable loop on the femoral side from November 2016 to October 2018. The knee’s functional outcome was evaluated using an International Knee Documentation Committee (IKDC) score, Lysholm score, Lachman test, and pivot shift test. The patients were assessed preoperatively and finally postoperatively after two years of surgery. Thirty-two patients were analyzed. Significant improvement was obtained in the final clinical outcome of the patients. Twenty-seven patients (84.4%) were Lachman negative, and twenty-eight patients (87.5%) were pivot shift test negative, the mean Lysholm score was 96.91, and the IKDC score was 91.47 (p < 0.001). There was no infection, graft failure, or flexion restriction. Arthroscopic ACLR with an adjustable-loop suspensory device is a successful fixation method for femoral-side graft fixation and offers a similar functional outcome as with fixed-loop devices.

Clinical and radiological comparison of bioactive glass and poly-L-lactic acid/hydroxyapatite bioabsorbable interference screws for tibial graft fixation in anterior cruciate ligament reconstruction

BACKGROUND

Ligament reconstruction is still the main treatment modality for patients with a complete ligament rupture. The semitendinosus tendon, alone quadrupled or double folded and combined with the gracilis tendon, is still the most frequently used autologous graft for a reconstructive procedure. Absorbable interference screw usage has gained popularity in the past decade because they create less artifacts during MR imaging and tend to osteointegrate over the years, arguably leading to a more anatomic fixation. The purpose of this study was to compare the 5-year radiological and clinical results of two different tibial graft fixation screws.

HYPOTHESIS

We hypothesized that bioabsorbable interference screws made of bioactive glass would lead to higher rates of osteointegration, better overall clinical results, less foreign body reaction rates and less tibial tunnel widening when compared to the poly-L-lactic acid/hydroxyapatite (PLLA-HA) screws.

PATIENTS AND METHODS

Fifty-one patients treated with an anatomic single bundle ACL reconstruction between June 2015 and July 2016 at our institution were included in the study. The tibial graft was fixed with a bioactive glass screw in 24, and with a PLLA-HA in 27 patients. Tibial tunnel widening, foreign body reaction, osteointegration and resorption rates were evaluated and compared on a magnetic resonance scan at a minimum of 5 year postoperatively. Overall clinical results and side-to-side difference on KT-1000 were also analyzed in-between groups.

RESULTS

Tibial tunnel widening was similar for both groups. Foreign body reaction, while not statistically significant, was less aggressive when bioactive glass screws were used. Osteointegration and resorption rates of the bioactive glass screws were significantly higher than the PLLA-HA group (p=0.000). While all patients showed an overall improvement on postoperative scores (p=0.000), patients with a bioactive glass interference screw had statistically higher translational stability with KT-1000, compared to the poly-L-lactic acid/hydroxyapatite group (p=0.001).

DISCUSSION

At a minimum of 5 years, compared to conventional PLLA-HA interference screws, 45S5 bioactive glass screw provide higher resorption rates, are more highly biodegradable and provide overall good clinical results.

LEVEL OF EVIDENCE

III.

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.

Higher Rate of Patellofemoral Problems After Anterior Cruciate Ligament Reconstruction using Hamstring Autograft

Background: Patellofemoral problems are not uncommon among post-anterior cruciate ligament (ACL) reconstruction patients. Hamstring autograft harvesting-related factor is one of the suspected causes. A lack of tibiofemoral internal rotation force due to strength deficit causes the patella tends to shift laterally. Purposes: Peroneus longus tendon has been proposed as an alternative graft source due to its adequate tensile strength and minimal donor site morbidity to the knee biomechanics, including the patellofemoral joint. This tendon does not cross the knee joint and thus does not affect patellofemoral alignment and biomechanics. This study aims to compare patellofemoral problems between hamstring and peroneus longus autograft harvested-patients following ACL reconstruction. Material and methods: Thirty-one subjects who underwent primary single-bundle ACL reconstruction between September 2018 and September 2019 and met the inclusion criteria were grouped into the hamstring group (n=16) and peroneus longus group (n=15). Both groups were evaluated retrospectively. The follow-up assessment was conducted on the phase II rehabilitation program. The assessed variables were pain, crepitus, and the Indonesian-validated Kujala score. Results: No significant differences in pain and crepitus were found between both groups. There were significant differences in the Kujala score between both groups (P < .001). The peroneus longus group reported an averagely higher score than the hamstring group. Conclusion: Single bundle ACL reconstruction using peroneus longus tendon autograft produces less patellofemoral symptoms and functional limitation than using hamstring tendon autograft.

A Comparison of Quadriceps Tendon Autograft With Bone-Patellar Tendon-Bone Autograft and Hamstring Tendon Autograft for Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review and Quantitative Synthesis

OBJECTIVE

There is growing enthusiasm for the increased use of quadriceps tendon (QT) autograft for primary anterior cruciate ligament reconstruction (ACLR). The purpose of this analysis was to synthesize and quantitatively assess the available evidence comparing QT autograft with hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) autografts, regarding functional outcomes, knee stability, anterior knee pain, and revision rates.

DATA SOURCES

A search in MEDLINE, EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials for eligible studies up to May 2018 was conducted. Two reviewers selected studies based on inclusion criteria and assessed methodological quality. Outcomes analyzed were anterior knee pain, graft failure rates, knee stability, functional outcomes, and adverse events. Pooled analyses were performed for continuous and dichotomous variables where appropriate.

MAIN RESULTS

Ten studies (1 randomized trial and 9 nonrandomized cohorts) met our inclusion criteria, which included 1398 patients. The analysis showed no statistical difference in anterior knee pain when comparing QT and HT autografts, but a significant difference between QT and BPTB autografts [odds ratio, 0.15 (95% confidence interval, 0.08-0.27); P < 0.001]. There were no differences between all 3 autografts in revision rates, knee stability, and patient-reported functional outcomes.

CONCLUSIONS

Quadriceps tendon autograft is a suitable graft alternative for primary ACLR, as it achieves good clinical outcomes with a low incidence of anterior knee pain. Given the limited quality of the included studies, there is a need for a well-designed multicenter randomized control trial comparing QT autograft with other primary ACL autografts to confirm our findings.

LEVEL OF EVIDENCE

Level IV systematic review.

Long-Term Results of ACL Reconstruction Using a Nonanatomic Double-Bundle Technique with Extra-Articular Reinforcement

Extra-articular procedures for the improvement in rotational stability after anterior cruciate ligament (ACL) reconstruction have gained popularity in the last decade. This surgical gesture hoped to improve resistance to the high tensional forces affecting the ACL graft during cutting and pivoting movements of the lower extremity and eventually prevent ACL reconstruction failure. We performed this study to analyze the long-term results of patients undergoing ACL reconstruction using a nonanatomic double-bundle technique with an additional extra-articular augmentation. All the cases that underwent an ACL reconstruction using a nonanatomic double-bundle technique with an extra-articular reinforcement during the period between 1992 and 1997 were reviewed. The inclusion criteria for this study included a minimum follow-up of 10 years and age between 14 and 45 years at the time of the surgery. Forty patients were included in this series (34 males and 6 females). The mean Lysholm score after a minimum follow-up period of 10 years was 92.3 (standard deviation [SD], 9.4). The average preoperative Tegner score of the participants was 7.0 (SD, 1.1). This score decreased to 5.7 (SD, 1.2) at the end of follow-up. Follow-up X-rays were reviewed to assess the degenerative changes in the three knee compartments. Degenerative changes ≥ Kellgren-Lawrence grade 2 were observed in our six (15%) patients, all of them in the medial knee compartment. With these results, we conclude that double-bundle nonanatomic ACL reconstruction combined with an extra-articular reinforcement resembling the anterolateral ligament offers good overall long-term results, with relatively low rates of osteoarthritis.

Risk Factors Related to the Presence of Meniscal Injury and Irreparable Meniscal Tear at Primary Anterior Cruciate Ligament Reconstruction

Background:

Few studies have attempted to identify risk factors associated with irreparable meniscal tears at anterior cruciate ligament reconstruction (ACLR) and to describe follow-up data, such as the failure rate, after meniscal repair.

Purpose:

To investigate the associations of age, sex, body mass index (BMI), time to surgery (TTS), and preinjury Tegner score with the presence of meniscal injuries and irreparable meniscal tears at primary ACLR.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A retrospective review was performed on 784 patients who underwent primary ACLR by a single surgeon between 2005 and 2017 (406 men and 378 women; mean age, 25.8 years; mean BMI, 23.1; median TTS, 3 months; median preinjury Tegner score, 7). All patients had a minimum follow-up of 12 months (mean postoperative follow-up, 33.0 months). Multivariate logistic regression analysis was conducted to determine the association of patient variables with the presence of meniscal injuries and irreparable meniscal tears during primary ACLR.

Results:

The risk factor for medial meniscal injuries was TTS ≥3 months (odds ratio [OR], 4.213; 95% CI, 3.104-5.719; P < .001). The presence of irreparable medial meniscal tears increased with older age (OR, 1.053; 95% CI, 1.024-1.084; P < .001), higher BMI (OR, 1.077; 95% CI, 1.003-1.156; P = .042), and TTS ≥3 months (OR, 1.794; 95% CI, 1.046-3.078; P = .034). On multivariate analysis, none of the variables were significantly associated with lateral meniscal injuries and irreparable meniscal tears. The failure rate, defined as patients who needed additional medial meniscal surgery after medial meniscal repair, was 4.6%.

Conclusion:

Time from ACL injury to reconstruction of ≥3 months was strongly associated with medial meniscal injuries and irreparable medial meniscal tears at primary ACLR. Older age and increased BMI were also risk factors for the presence of irreparable medial meniscal tears at ACLR.

The long-term outcomes of different grafts in anterior cruciate ligament reconstruction: a network meta-analysis

OBJECTIVES

To compare the long-term prognosis of patients with different types of grafts used in anterior cruciate ligament reconstruction (ACLR).

METHODS

PubMed, Ovid (MEDLINE and Embase) and the Cochrane library were searched up to Feb 2020. Eligible studies about different grafts in ACLR were searched for identifying the evidence comparing the long-term (mean or median follow-up time or the general description of the follow-up time≥2 years) knee outcomes of different grafts for ACLR. The final included articles and evaluation criteria were confirmed by the authors and senior clinicians to ensure the validity of the included articles. Lysholm score, the results of pivot shift test, Lachman test and International Knee Documentation Committee (IKDC) evaluation were selected as prognostic indicators. A Bayesian network meta-analysis was conducted.

RESULTS

A total of 30 articles were included in our network meta-analysis. Finally, we found that artificial graft or augmentation can provide the not bad Lysholm score but the worse result of IKDC evaluation for patients with ACLR compared with other types of grafts. Double-bundle hamstring autograft can provide a good Lysholm score as well as lower positive rate of pivot shift test and Lachman test. Patellar tendon autograft can provide the better result of IKDC evaluation. The patients with allogeneic tendon graft may get the higher positive rate of pivot shift test and Lachman test. Patients with single-bundle hamstring autograft may get the ordinary result of IKDC evaluation and Lysholm score.

CONCLUSIONS

Double-bundle hamstring autograft may be a better choice because of more items of good prognosis for the patients with ACLR. Patellar tendon autograft is a right choice which only shows the disadvantage on the Lysholm score. The prognosis of patients with single-bundle hamstring autograft is ordinary. The effect of artificial graft or augmentation needs more evidence to prove. Allogeneic tendon graft is not a better choice when compared with other grafts referred in our network meta-analysis.

TRANSLATIONAL POTENTIAL STATEMENT

In this study, we made a comprehensive comparison of the grafts commonly used in anterior cruciate ligament reconstruction. The evidence presented in this study provides a reference for clinicians to select a suitable anterior cruciate ligament graft.

Outcome of bone-patellar tendon-bone vs hamstring tendon autograft for anterior cruciate ligament reconstruction: A meta-analysis of randomized controlled trials with a 5-year minimum follow-up

BACKGROUND

Many systematic reviews have compared the short-term outcomes of anterior cruciate ligment (ACL)reconstruction with hamstring and patellar tendon autograft,but few differences have been observed. The purpose of this meta-analysis was to compare the medium-term outcome of bone-patellar tendon-bone and hamstring tendon autograft for anterior cruciate ligament reconstruction in terms of clinical function, knee stability, postoperativecomplications, and osteoarthritis changes.

METHODS

This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, and the Cochrane Library databases were searched from inception to November 2, 2019. This meta-analysis included only randomized controlled trials that compared BPTB and HT autografts for ACL reconstruction with a 5-year minimum follow-up. The Cochrane Collaboration's risk-of-bias tool was used to estimate the risk-of-bias for all included studies. RevMan 5.3 software was used to performed statistical analysis of the outcomes.

RESULTS

Fifteen RCTs, involving 1298 patients (610 patients in the BPTB group and 688 patients in the HT group) were included. In terms of clinical function, no significant difference was found in the objective International Knee Documentation Committee score (OR = 0.94, 95%CI: 0.64-1.37, P = .75), Lysholm knee score (MD = -2.26, 95%CI: -4.56 to 0.05, P = .06), return to preinjury activity level (OR = 1.01, 95%CI: 0.67-1.52, P = .96), and Tegner activity level (OR = 0.03, 95%CI: -0.36 to 0.41, P = .89). There was no statistically significant difference in the Lachman test (OR = 0.86, 95%CI: 0.5-1.32, P = .50), pivot-shift test (OR = 0.68, 95%CI: 0.44-1.06, P = .09), and side-to-side difference (MD = -0.32, 95%CI: -0.81 to 0.16, P = .19). As for postoperative complications and OA changes, there were no statistically significant difference in flexion loss (OR = 1.09, 95%CI: 0.47-2.54, P = .85) and OA changes (OR = 0.76, 95%CI: 0.52-1.10, P = .15), but we found significant differences in favor of the HT group in the domains of kneeling pain (OR = 1.67, 95%CI: 1.04-2.69, P = .03), anterior knee pain (OR = 2.90, 95%CI: 1.46-5.77, P = .002), and extension loss (OR = 1.75, 95%CI: 1.12-2.75, P = .01). There was a significant difference in favor of the BPTB group in the domain of graft failure (OR = 0.59, 95%CI: 0.38-0.91, P = .02).

CONCLUSIONS

Based on the results above, HT autograft is comparable with the BPTB autograft in terms of clinical function, postoperative knee stability, and OA changes, with a medium-term follow-up. The HT autograft for ACL reconstruction carries a lower risk of complications, such as anterior knee pain, kneeling pain, and extension loss, but an increased incidence of graft failure. Patients should be informed of the differences when deciding on graft choice with their physician.

Investigation of Hamstring Tendon Graft Fixation for the Reconstruction of Anterior Cruciate Ligament using Interference Screw Merely or in Combination with Supplementary Staple: A Clinical Trial

BACKGROUND

Hamstring graft tendon for anterior cruciate ligament (ACL) reconstruction is a common approach worldwide. Tibial side graft fixation to achieve appropriate stability is a serious concern, worldwide. The current study aims to compare the outcomes of mere use of interference screw for fixation of hamstring tendon graft versus the use of interference screw plus supplementary staple.

MATERIALS AND METHODS

This is a randomized clinical trial conducted on 53 patients who underwent ACL reconstruction from 2016 to 2018. The study population was randomly divided into two groups: graft fixation with interference screw only and interference screw plus supplementary staple. Postoperative recovery time, postoperative clinical examinations, and the scale of the International Knee Documentation Committee were assessed for participants and compared between two groups.

RESULTS

Comparison of two groups regarding demographic information, including age, gender distribution, postoperative recovery time, and body mass index, showed no statistical difference (P > 0.05). Postoperative Pivot test was insignificantly positive in 4 (16.7%) cases of screw interference with supplementary staple while it was positive in 3 (10.7%) cases with screw interference only approach (P = 0.98). IKCD index was not statistically different between two groups postoperatively (P = 0.72), while IKCD scores changed significantly following the surgical procedure, regardless of the type of the surgical procedure (P < 0.001).

CONCLUSION

Use of supplementary staple beside interference screw was as successful as mere use of interference screw for fixation of hamstring tendon autologous graft of the ACL reconstruction, regarding force withstanding. The comparison of the two approaches revealed no remarkable difference.

Patellar Tendon Versus 4-Strand Semitendinosus and Gracilis Autografts for Anterior Cruciate Ligament Reconstruction: A Meta-analysis of Randomized Controlled Trials With Mid- to Long-Term Follow-Up

PURPOSE

To compare patellar tendon (PT) autografts with 4-strand semitendinosus and gracilis (STG) autografts concerning knee stability, functional outcomes, as well as complications after anterior cruciate ligament (ACL) reconstruction at minimal follow-up of 5 years.

METHODS

A systematic search of the literature was performed in PubMed, Embase, and the Cochrane Library to identify published prospective randomized controlled trials on clinical studies comparing PT autograft and 4-strand STG autografts for ACL reconstruction. The results of the eligible studies were analyzed in terms of knee stability (laxity measurements, Lachman test, and pivot-shift test), functional outcomes (Lysholm score, International Knee Documentation Committee score, Cincinnati score, Tegner score, single-legged hop test, and return to preinjury activity level), and complications (loss of range of motion [ROM], pain, graft re-rupture, revision, and osteoarthritis [OA]).

RESULTS

Nine clinical studies with 630 patients (313 PT and 317 STG autografts) met the inclusion criteria. No statistically significant differences were found between the PT and STG group in Lachman test, pivot-shift test, International Knee Documentation Committee score, Cincinnati score, loss of ROM, kneeling pain, graft re-rupture rate, revision rate, and OA rate. The STG group was found with less anterior knee pain (P = .003). There were no clinically significant differences for the outcomes of SSD, Lysholm score, and Tegner score.

CONCLUSIONS

Except for significantly greater risk of anterior knee pain, PT autograft had comparable results with 4-strand STG autograft in terms of knee stability and functional outcomes after ACL reconstruction with mid- to long-term follow-up. Besides, we found no statistically significant difference in loss of ROM, kneeling pain, graft re-rupture rate, revision rate, and OA change, but these results were underpowered.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

Clinical Outcomes of the Central Third Patellar Tendon Versus Four-strand Hamstring Tendon Autograft Used for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Subgroup Meta-analysis of Randomized Controlled Trials

BACKGROUND

The most frequently used auto-grafts for ACL reconstruction (ACLR) are bone-patellar tendon-bone (BPTB) and four-strand hamstring tendon (4S-HT), but significant controversy exists about which graft is better. This study aimed to compare the knee outcomes following ACLR with BPTB and 4S-HT autografts.

METHODS

Subgroup meta-analyses were performed basing on available randomised controlled trials (RCTs) according to different follow-up intervals. 23 RCTs were eligible for inclusion, involving 933 participants in each treatment group.

RESULTS

Only short-term (≤2 years) knee anteroposterior and rotational stability were significantly poorer with 4S-HT when compared to BPTB autograft, as judged by side-to-side difference on knee laxity (WMD=-0.50, 95%CI -0.81~-0.18, p=0.002) and pivot-shift test (OR=0.58, 95%CI 0.39~0.88, p=0.010), respectively. The IKDC objective grade was evident to be in favour of 4S-HT group in mid-term (3-5 years) follow-up (OR=0.63, 95%CI 0.43~0.92, p=0.017). Several donor-site related complications, including anterior knee pain, pain with kneeling and extension deficit, were more frequent in BPTB autograft group, while lower short-term iskinetic peak flexion torques both at 60°/S (WMD=8.93, 95%CI 7.88~9.99, p<0.001) and 240°/S (WMD=11.63, 95%CI 9.92~13.34, p<0.001) were caused by HT harvesting.

CONCLUSION

BPTB was associated with inferior mid- to long-term (>5 years) knee functional outcomes, and increased frequency of donor-site complications. In contrast, only short-term knee laxity was increased for 4S-HT autograft, which is expected to be improved by providing more conservative rehabilitation protocol and aperture fixation methods.

Biomechanical Properties of Small-Size Hamstring Autografts

Purpose

To evaluate small-size hamstring (HS) autografts for biomechanical properties and determine a threshold diameter necessary for appropriate reconstruction.

Methods

In a controlled laboratory setting, biomechanical testing was performed upon 15 hamstring autografts. The grafts were divided into three groups by diameter, with five grafts each at diameter sizes of 6, 7, and 8 mm. Testing of the specimens was performed using an MTS 858 (Materials Testing System, Eden Prairie, MN). We determined load to failure by looking at the maximum load as well as the stiffness of the graft. Statistical analysis was performed via analysis of variance (ANOVA) testing with Tukey's post-hoc test and P-values set at 0.05.

Results

There was a significant difference in ultimate tensile strength for the different size grafts: 1990 +/- 302.42 N for 6 mm grafts (n=5), 2179 +/- 685.36 N for the 7 mm grafts (n=5), and 3074 +/- 781 N for 8 mm grafts (n=5). This was statistically significant for the group overall (p=0.039), as well as between the 6 mm and 8 mm grafts (p=0.044). Graft stiffness for the 6 mm grafts was 317 +/- 85 N (n=5), 288.6 +/- 66 for 7 mm grafts (n=5), and 428.053 +/- 83 for 8 mm grafts (n=5). This achieved statistical significance for the group overall (p =0.037) as well as between the 8 mm and 7 mm grafts.

Conclusions

The biomechanical data presented here demonstrate that graft diameter is highly correlated with ultimate tensile strength and stiffness.

Clinical relevance

When viewing this biomechanical data in conjunction with prior clinical data, consideration should be given for the supplementation of an HS autograft as the size decreases below 8 mm.

All-Inside Quadrupled Semitendinosus Autograft Shows Stability Equivalent to Patellar Tendon Autograft Anterior Cruciate Ligament Reconstruction: Randomized Controlled Trial in Athletes 24 Years or Younger

PURPOSE

To compare clinical outcomes of knee anterior cruciate ligament (ACL) autograft reconstruction using all-inside quadrupled semitendinosus (AIST) versus bone-patellar tendon-bone (BPTB) in a high-risk athletic population 24 years or younger.

METHODS

Skeletally mature candidates younger than 24 years old with an ACL tear were randomized into either the AIST (n = 32) or BPTB (n = 32) group and were followed for 2 years. Magnetic resonance imaging scans were obtained at 1-year follow-up, and radiographs were obtained at 2-year follow-up. All surgeries were performed by a single surgeon using an anteromedial portal to establish the femoral tunnel. The primary outcome measure was KT-1000 stability testing. Secondary outcome measures included International Knee Documentation Committee (IKDC) Knee Evaluation Form, IKDC Subjective Form, Knee Injury and Osteoarthritis Outcome Score, Marx Activity Scale, visual analog pain scale, and SF-12 (Mental and Physical).

RESULTS

At 2-year follow-up, no statistical difference existed with KT-1000-measured side-to-side laxity between AIST (0.3 ± 0.7 mm, 95% confidence interval 0.0-1.0 mm) and BPTB (0.0 ± 0.8 mm, confidence interval CI -0.3 to 1.1 mm) (P = .197). In addition, no statistical differences between the groups were found for IKDC Subjective Form, Knee Injury and Osteoarthritis Outcome Score, Marx, SF-12 Mental, SF-12 Physical, or with regards to imaging findings. Patients with BPTB reported significantly greater postoperative pain scores at days 2 (P = .049), 3 (P = .004), and 7 (P = .015) and had significantly greater kneeling pain at 2 years (P < .019). A return to sport questionnaire at 2 years revealed no significant difference between the groups for returning to preoperative level of sport activity (83% AIST, 74% BPTB; P = .415). Two graft retears (7%; P = .222) occurred in the AIST group. Three patients in the BPTB group experienced ACL tears in the contralateral knee (9%; P = .239).

CONCLUSIONS

ACL reconstruction with an all-inside quadrupled semitendinosus autograft construct is equivalent to patellar BPTB autograft based on KT-1000 stability testing in athletes 24 years or younger.

LEVEL OF EVIDENCE

randomized controlled trial with 92% 2-year follow-up, Level I.

Bone-Patellar Tendon-Bone Autografts Versus Hamstring Autografts Using the Same Suspensory Fixations in ACL Reconstruction: A Systematic Review and Meta-analysis

Background:

Bone–patellar tendon–bone (BPB) autografts and hamstring tendon (HT) autografts are 2 popular choices for anterior cruciate ligament reconstruction (ACLR). Although existing meta-analyses have explored the clinical outcomes between BPB and HT autografts, none have based their analysis on studies with just femoral suspensory fixation methods.

Purpose:

To evaluate and compare clinical outcomes, particularly graft failure and knee stability, of ACLR with BPB or HT autografts with suspensory femoral fixation.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A literature search was conducted of studies reporting single-bundle ACLR with BPB autografts and HT autografts with suspensory fixation with a minimum 24-month follow-up. Graft failure rate, knee stability, and clinical outcomes were compared for BPB versus HT autografts. Knee stability was measured with the Lachman test, pivot-shift test, and KT-1000/2000 arthrometer side-to-side difference (SSD). Clinical outcomes were measured with Lysholm scores and the Tegner activity scale, as well as rate of return to preinjury sports. Donor site morbidity among included studies was reviewed. A random-effects model was used for calculations of summary estimates. Subgroup, sensitivity, and trial sequential analyses were conducted.

Results:

Five studies were included. Graft failure was seen more often in the HT group than the BPB group, and this was statistically significant (P = .03). However, the trial sequential analysis outcome indicated that the included sample size was not large enough to support a solid positive finding. The analysis showed no significant difference in SSD, Lachman test, pivot-shift test, rate of return to sports, Lysholm score, or Tegner score between groups. Subgroup analyses found no significant difference between groups.

Conclusion:

This meta-analysis demonstrated no significant differences in knee stability and knee functional outcomes between BPB and HT autografts with suspensory fixation. More evidence is needed to prove the lower risk of failure with use of BTB autograft with suspensory fixation.

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.

Comparison of patellar tendon versus hamstrings autografts for anterior cruciate ligament reconstruction in Indian population: A randomised control trial study

Disruption of anterior cruciate ligament (ACL) is a common ligamentous injury of the knee. The best choice of graft for reconstruction remains undecided. This prospective, randomized clinical trial aimed to compare clinical results of bone-patellar tendon-bone (BPTB) grafts and four-strand semitendinosus-gracilis (QHT) grafts for ACL reconstruction over a 1-year follow-up interval in Indian population.

METHODS

42 consecutive patients with ACL injury were recruited, by pick and draw method and allotted into two groups with 21 patients in each group. Group A patients underwent arthroscopic ACL reconstruction using BPTB graft while QHT autograft was used for patients in Group B. All the patients underwent standard ipsilateral arthroscopic ACL reconstruction procedure using a single incision, antero-medial (AM) portal technique for BPTB or the QHT autograft by a same surgeon. Patients were followed up regularly for a minimum period of 1 year.

RESULTS

After one year, the Cincinnati score was 91 ± 4.117 in BPTB group and 89.29 ± 5.371 in QHT group (P = 0.282). There was no significant difference between the two groups in the mean scores with respect to pain, overall activity level and running in the Cincinnati score. None of the patients complained of the knee giving way. Similarly, at 1 year, the Lysholm score was 92.84 ± 2.630 and 90.55 ± 2.395 in the two groups respectively (P = 0.842). There were no episodes of locking or instability and there was no significant difference in the mean Lysholm scores regarding pain and squatting.

CONCLUSION

There was no significant functional difference between the two grafts in terms of Lysholm and the Cincinnati score, anterior knee laxity and altered sensation over proximal leg. The patients with QHT groups performed better than BPTB functionally at 6 month so early return to sport is possible even with QHT autograft.

Prior Anterior Cruciate Ligament Reconstruction Effects on Future Total Knee Arthroplasty

BACKGROUND

The impact of prior anterior cruciate ligament (ACL) reconstruction on total knee arthroplasty (TKA) has rarely been studied. The objective of this study was to compare intraoperative characteristics in patients who underwent TKA with pre-existing hardware from prior ACL reconstruction with a matched cohort control group.

METHODS

A retrospective study of patients who had undergone primary TKA with pre-existing hardware from prior ACL reconstruction was performed from June 2012 through June 2017. These patients were 2-to-1 matched to the ACL group based on similar patient demographic and provider variables. Outcomes investigated included operative time, estimated blood loss (EBL), and postoperative complications.

RESULTS

One hundred one patients met the inclusion/exclusion criteria. The mean age was 54 ± 9 years, and the mean body mass index was 32.6 ± 6.5 kg/m². The ACL group was divided into 4 subgroups: group 1, no pre-existing hardware removed (22 TKAs); group 2, pre-existing hardware removed from the femur only (8 TKAs); group 3, pre-existing hardware removed from the tibia only (45 TKAs); and group 4, pre-existing hardware removed from both the femur and tibia (26 TKAs). There was no statistical difference in EBL and postoperative complication between the ACL group and controls. Statistical differences were detected between 2 subgroups regarding mean operative time variables: ACL group 3 (74 ± 23 minutes; control: 64 ± 21 minutes, P = .020) and group 4 (79 ± 24 minutes; control: 65 ± 19 minutes, P = .010).

CONCLUSION

Hardware retained, especially on the tibia, from prior ACL reconstruction has a major impact on TKA surgical procedure operative time but not on EBL and/or complications.

Double-Bundle Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Hybrid Grafts in Patients Over 40 Years of Age: Comparisons Between Different Age Groups

Background:

Several recent studies have reported that favorable clinical results and a high level of patient satisfaction can generally be obtained with no increased risk of complications after single-bundle anterior cruciate ligament (ACL) reconstruction performed in patients >40 years of age. However, no studies have yet clarified the age-based differences in clinical outcomes after double-bundle reconstruction.

Purpose:

To compare clinical outcomes after double-bundle ACL reconstruction using hamstring tendon hybrid grafts between patients in 2 different age groups: ≥40 years and <40 years.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective study was conducted using 96 patients (48 men, 48 women ; mean age, 37 years) who underwent unilateral ACL reconstruction between 2008 and 2011. These patients were divided into 2 groups: group M included patients ≥40 years of age (n = 40 patients), and group Y included patients <40 years of age (n = 56 patients). All patients underwent the same anatomic double-bundle ACL reconstruction procedure. Clinical outcomes were evaluated at 2 years after surgery. Tunnel enlargement was also evaluated by computed digital radiography at 1 week and 2 years after surgery.

Results:

Mean postoperative side-to-side differences in anterior laxity were 0.5 ± 1.9 mm and 1.2 ± 1.5 mm in groups M and Y, respectively; there was a significant difference between the 2 groups (P = .039). There were no significant differences between the groups in Lysholm knee scores, International Knee Documentation Committee (IKDC) scores, or peak muscle torque of the hamstring. On the other hand, peak muscle torque of the quadriceps was significantly lower in group M (81%) than in group Y (89%) (P = .025). With respect to femoral tunnel enlargement, the posterolateral tunnel in group M was significantly larger than that in group Y on anteroposterior and lateral radiographs (P = .015 and P = .002, respectively).

Conclusion:

Equivalent clinical outcomes were seen between the 2 age groups after double-bundle ACL reconstruction. Postoperative anterior laxity was significantly less in older patients than in younger patients, however, older patients had significantly less quadriceps muscle strength than younger patients. Surgeons should be aware of residual muscle weakness and tunnel enlargement when performing double-bundle ACL reconstruction in older patients.

Quadriceps Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the current evidence to ascertain whether quadriceps tendon autograft (QT) is a viable option in anterior cruciate ligament reconstruction.

METHODS

A literature review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Cohort studies comparing QT with bone-patellar tendon-bone autograft (BPTB) or hamstring tendon autograft (HT) were included. Clinical outcomes were compared, with all statistical analyses performed using IBM SPSS Statistics for Windows, version 22.0, with P < .05 being considered statistically significant.

RESULTS

We identified 15 clinical trials with 1,910 patients. In all included studies, QT resulted in lower rates of anterior knee pain than BPTB. There was no difference in the rate of graft rupture between QT and BPTB or HT in any of the studies reporting this. One study found that QT resulted in greater knee stability than BPTB, and another study found increased stability compared with HT. One study found that QT resulted in improved functional outcomes compared with BPTB, and another found improved outcomes compared with HT, but one study found worse outcomes compared with BPTB.

CONCLUSIONS

Current literature suggests QT is a viable option in anterior cruciate ligament reconstruction, with published literature showing comparable knee stability, functional outcomes, donor-site morbidity, and rerupture rates compared with BPTB and HT.

LEVEL OF EVIDENCE

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

There is no difference between quadriceps- and hamstring tendon autografts in primary anterior cruciate ligament reconstruction: a 2-year patient-reported outcome study

PURPOSE

Graft choice for anterior cruciate ligament (ACL) reconstruction is crucial, however the optimal graft source remains a topic of controversy. The purpose of this study is to compare subjective and functional patient-reported outcomes (PRO) after single-bundle ACL reconstruction using quadriceps tendon (QT) or hamstring tendon (HT) autografts for single-bundle ACL reconstruction. We hypothesize that there is no difference in patient-reported functional outcomes after ACL reconstruction using either HT- or QT autograft.

METHODS

All data were extracted from a prospectively collected ACL registry. A total of 80 patients with at least 2-year follow-up were included in this study. A total of 40 patients with primary ACL reconstruction using a QT autograft harvested via a minimally invasive technique were matched by sex, age and pre-injury Tegner and Lysholm score to 40 patients who received HT autografts. Subjective and functional PRO scores including Lysholm score, Tegner activity level and visual analogue scale for pain were obtained at 6, 12 and 24 months after index surgery.

RESULTS

No significant difference between the QT and the HT group was seen at any follow-up in regard to any of the PRO scores for function or pain. 24 months post-surgery the mean Tegner activity score of the HT group was significantly (p = 0.04) lower compared to the pre-injury status. At final follow-up, 27 patients (67.5%) in the QT group and 32 patients (80.0%) in the HT returned to their pre-injury activity level (n.s.). A total of 37 patients (92.5%) of the QT cohort and 35 patients (87.5%) of the HT cohort reported "good" or "excellent" results according to the Lysholm score (n.s.). "No pain" or "slight pain" during severe exertion was reported by 33 patients (82.5%) with QT autograft and 28 patients (82.4%) with HT autograft (n.s.).

CONCLUSION

There is no significant difference between PRO 2 years post-operative using either QT or HT autografts. Both QT and HT grafts show acceptable and comparable PRO scores making the QT a reliable graft alternative to HT for primary ACL reconstruction.

LEVEL OF EVIDENCE

III.

Over-the-top ACL Reconstruction Plus Extra-articular Lateral Tenodesis With Hamstring Tendon Grafts: Prospective Evaluation With 20-Year Minimum Follow-up

BACKGROUND

There are few published studies with very long-term follow-up of combined intra- and extra-articular anterior cruciate ligament (ACL) reconstruction.

PURPOSE

To analyze clinical and radiographic outcomes of over-the-top ACL reconstruction plus extra-articular lateral tenodesis with autologous hamstrings at minimum 20-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Of 60 originally eligible patients who underwent over-the-top ACL reconstruction with double-stranded hamstring tendon (leaving intact graft tibial insertions) and extra-articular lateral plasty (performed with the remnant part of tendons), 52 were prospectively evaluated at a minimum 20-year follow-up (mean follow-up, 24 years; 41 men, 11 women; mean age at time of surgery, 25.5 ± 7.6 years). Twenty-nine patients were available for prospective evaluations: clinical (Lysholm, Tegner, and objective International Knee Documentation Committee [IKDC]), instrumented (KT-2000), and radiographic (standard, long-standing, and Merchant views). Subjective KOOS (Knee injury and Osteoarthritis Outcome Score) and objective inertial sensor pivot-shift analysis (KiRA) were carried out at final follow-up. Twenty-three patients were investigated by phone interview for subjective Tegner score and documented complications, rerupture, or revision surgery.

RESULTS

At final follow-up, mean Lysholm score was 85.7 ± 14.6; median Tegner score, 4 (range, 3-5); sport activity resumption, 86.2%; and objective IKDC score, good or excellent in 86% of patients (31%, A; 55%, B). Only 3 of 26 patients (12%) had >5-mm manual maximum KT-2000 side-to-side difference. KiRA system documented positive pivot-shift (>0.9-m/s² tibial acceleration side-to-side difference) in these 3 of 26 patients (12%). Statistically significant changes were as follows: decrease in Tegner score from 7 (range, 6-8) at 5-year follow-up to 4 (range, 3-5) at 10 years ( P < .0001) and decrease in Lysholm score from 96.1 ± 7.3 at 10-year follow-up to 85.7 ± 14.6 at 20 years ( P = .0003). Radiographic evaluation demonstrated significant difference of medial joint space between injured and healthy knees in patients with concomitant medial meniscectomy (n = 8, 3.2 ± 0.6 vs 5.0 ± 1.8 mm, P = .0114). No significant differences were reported regarding lateral or patellofemoral joint space. One patient (2%) experienced rerupture, with 3 of 52 (5.8%) having a contralateral ACL injury (excluded from KT-2000 and radiographic evaluations). Overall, 4 of 29 clinical failures (objective IKDC, KT-2000) and 1 rerupture among 52 patients were registered at final follow-up.

CONCLUSION

Studied surgical technique demonstrated good results in laxity control at 20-year minimum follow-up. The lateral extra-articular plasty associated with ACL reconstruction did not generate lateral knee or patellofemoral osteoarthritis. The factor increasing osteoarthritis was meniscectomy.

Hamstring Autograft versus Patellar Tendon Autograft for ACL Reconstruction: Is There a Difference in Graft Failure Rate? A Meta-analysis of 47,613 Patients

BACKGROUND

Bone-patellar tendon-bone (bone-tendon-bone) and four-strand hamstring tendon grafts (hamstring) are the most commonly utilized autografts for primary anterior cruciate ligament (ACL) reconstruction. Existing clinical trials, registry studies, and meta-analyses offer conflicting opinions regarding the most favorable graft choice.

QUESTIONS/PURPOSES

Which graft type for ACL reconstruction (bone-tendon-bone or hamstring) has a higher risk of (1) graft rupture and/or (2) graft laxity?

METHODS

We performed a meta-analysis of randomized controlled trials (RCTs), prospective cohort studies, and high-quality national registry studies to compare the outcomes of primary ACL reconstruction with bone-tendon-bone autograft or hamstring autograft. Studies that compared these graft types were identified through a comprehensive search of electronic databases (PubMed, MEDLINE, EMBASE, and the Cochrane Library). Two independent reviewers utilized the Jadad scale for RCT study quality and the Modified Coleman Methodology Score for prospective comparative and registry study quality. The included studies were analyzed for the primary outcome measure of graft rupture with or without revision ACL surgery. In surviving grafts, secondary outcomes of graft laxity were quantified by KT1000/2000™ testing, a positive pivot shift test, and a positive Lachman test. Meta-analysis was performed with Review Manager. A total of 47,613 ACL reconstructions (39,768 bone-tendon-bone and 7845 hamstring) from 14 RCTs, 10 prospective comparative studies, and one high-quality national registry study were included in this meta-analysis. Mean age was 28 years in both groups. Sixty-three percent of patients in the bone-tendon-bone cohort were men versus 57% of patients in the hamstring cohort. Mean followup was 68 ± 55 months.

RESULTS

Two hundred twelve of 7560 (2.80%) bone-tendon-bone grafts ruptured compared with 1123 of 39,510 (2.84%) in the hamstring group (odds ratio = 0.83, 95% confidence interval, 0.72-0.96; p = 0.01). The number needed to treat analysis found that 235 patients would need to be treated with a bone-tendon-bone graft over a hamstring tendon graft to prevent one graft rupture. Instrumented laxity analysis showed that 22% (318 of 1433) of patients in the bone-tendon-bone group had laxity compared with 18% (869 of 4783) in the hamstring tendon group (odds ratio = 0.86; p = 0.16). Pivot shift analysis showed a positive pivot shift in 19% (291 of 1508) of the bone-tendon-bone group compared with 17% (844 of 5062) in the hamstring group (odds ratio = 0.89; p = 0.51). Lachman testing showed a positive Lachman in 25% (71 of 280) of patients receiving bone-tendon-bone grafts compared with 25% (73 of 288) in the hamstring group (odds ratio = 0.96; p = 0.84).

CONCLUSIONS

In this meta-analysis of short- to mid-term followup after primary ACL reconstruction, hamstring autografts failed at a higher rate than bone-tendon-bone autografts. However, failure rates were low in each group, the difference observed was small, and we observed few differences between graft types in terms of laxity. Both graft types remain viable options for primary ACL reconstruction, and the difference in failure rate should be one part of a larger conversation with each individual patient about graft selection that should also include potential differences in donor site morbidity, complication rates, and patient-reported outcome measures. Continued prospective collection of patient data will be important going forward as we attempt to further characterize the potential differences in outcomes attributable to graft selection.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Suspensory Versus Aperture Fixation of a Quadrupled Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Meta-analysis

BACKGROUND

Hamstring grafts have become a popular choice for anterior cruciate ligament (ACL) reconstruction; however, the most effective means of fixation of these soft tissue grafts is unknown.

PURPOSE

To determine whether suspensory or aperture fixation of hamstring tendon autografts provides better stability and clinical outcomes in ACL reconstruction.

STUDY DESIGN

Meta-analysis.

METHODS

A literature search of studies reporting single-bundle ACL reconstructions using 4-stranded hamstring tendon autografts with aperture or suspensory fixation with a minimum 24-month follow-up was conducted. Stability and clinical outcomes were compared for aperture versus suspensory fixation. Knee stability was measured with the Lachman or pivot-shift test or KT-1000 arthrometer side-to-side difference (SSD), and outcomes were determined with the International Knee Documentation Committee (IKDC), Tegner, and Lysholm scores as well as graft failures. A random-effects model with a pooled estimate for the between-study variance was used to estimate proportions or means for each outcome and its corresponding 95% CI.

RESULTS

Forty-one studies were included, of which 20 utilized suspensory fixation techniques and 21 utilized aperture fixation techniques. A >3-mm SSD was seen more often in the aperture group than the suspensory group, which was statistically significant ( P < .0001), but there was no significant difference between groups for a >5-mm SSD ( P = .53). The aperture group demonstrated significantly more graft ruptures than did the suspensory group ( P = .03). There were no statistically significant differences in Lachman grade 0 ( P = .76), grade 1 ( P = .89), and grade 2 ( P = .55) or pivot-shift grade 0 ( P = .72), grade 1 ( P = .97), and grade 2 ( P = .28). There was no statistically significant difference in mean continuous IKDC ( P = .80), Tegner ( P = .34), or Lysholm ( P = .84) scores.

CONCLUSION

This meta-analysis demonstrated improved overall arthrometric stability and fewer graft ruptures using suspensory fixation compared with aperture fixation of a quadrupled hamstring tendon autograft in ACL reconstruction. There were no differences in IKDC, Lysholm, Lachman, and pivot-shift outcomes between suspensory and aperture fixation.

Long-Term Outcomes in Anterior Cruciate Ligament Reconstruction: A Systematic Review of Patellar Tendon Versus Hamstring Autografts

Background:

Much controversy still exists surrounding graft choice in anterior cruciate ligament (ACL) reconstruction. Over the past decade, an increase in comparative studies with longer follow-up has enhanced our understanding of current graft options and outcomes.

Purpose:

To describe the long-term comparative outcomes of ACL reconstruction with autograft bone–patellar tendon–bone (BPTB) versus autograft hamstring (HS) ACL reconstruction with regard to clinical and radiographic outcomes.

Study Design:

Systematic review; Level of evidence, 2.

Methods:

A search of the PubMed, MEDLINE, Cochrane, and Scopus databases was performed to identify studies in the English language with outcome data comparing ACL reconstruction utilizing autograft BPTB and autograft HS; only studies with a minimum 5-year follow-up were included. Outcome data included failure and complications, manual and instrumented laxity, patient-reported outcomes, and radiographic risk of osteoarthritis.

Results:

Twelve studies with a total of 953 patients met the inclusion criteria. Of these studies, 8 were level 1 evidence and 2 were level 2. Mean follow-up was 8.96 years (range, 5-15.3 years). No differences in graft failure or manual or instrumented laxity were seen in any studies. Lower clinical outcomes scores and greater motion loss were seen in BPTB patients in 1 and 2 studies, respectively. Two of 4 studies reporting on anterior knee pain, and 3 of 7 that recorded kneeling pain found it more frequently among BPTB patients. One study found significantly increased reoperation rates in HS patients, while another found a similar result in BPTB, and 1 study reported a significant increase in contralateral ACL tears in BPTB patients. Three of 5 studies reporting on radiographic evidence of osteoarthritis noted significantly increased rates in BPTB patients.

Conclusion:

This systematic review comparing long-term outcomes after ACL reconstruction with either autograft BPTB or autograft HS suggests no significant differences in manual/instrumented laxity and graft failures between graft types. An increase in long-term anterior knee pain, kneeling pain, and higher rates of osteoarthritis were noted with BPTB graft use.

Effects of polyvinylpyrrolidone-iodine on tendon-bone healing in a rabbit extra-articular model

Polyvinylpyrrolidone-iodine (PVP-I) is a broad-spectrum antimicrobial agent, but its effects on tendon-bone healing are unclear. The purpose of this study was to investigate the effects of PVP-I on bone marrow mesenchymal stem cells (BMSCs) in vitro and on tendon-bone healing in vivo. In this study, following investigation of the concentration-dependent effects of PVP-I on the viability and osteogenic differentiation of BMSCs, the appropriate concentration of PVP-I was selected for animal experiments. New Zealand white rabbits received autologous tendon transplantation with and without PVP-I treatment of the graft tendon. Subsequently, histological examination, biomechanical testing and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses were conducted. At 6 weeks post-surgery, connective tissue and osteogenesis was observed at the tendon-bone interface in the PVP-I group. At 12 weeks post-surgery, the interface width in the PVP-I group was much narrower compared with that of the control group. Furthermore, the biomechanical properties of the PVP-I group were significantly stronger than those in the control group (P<0.05). RT-qPCR examination revealed that the mRNA levels of bone morphogenetic protein-2 and osteopontin in the PVP-I group were higher than those in the control group at 6 weeks (P<0.05). In conclusion, these results indicated that PVP-I promoted tendon-bone healing via osteogenesis.

Factors Associated With Improved Function and Maintenance of Sports Activities at 5 to 10 Years After Autologous Hamstring ACL Reconstruction in Young Men

Background:

There are limited data regarding associated factors of return to sports activities at more than 5 years after anterior cruciate ligament (ACL) reconstruction.

Purpose:

To test interrelationships between patient characteristics, concomitant articular lesions, graft laxity, and maintenance of sports activities at 5 to 10 years after ACL reconstruction. It was hypothesized that at 5 to 10 years after the operation in young adult men, maintenance of greater activity level and better knee function would be associated with greater preinjury activity level, younger age at reconstruction, absence of concomitant articular lesions, and minimal graft laxity at follow-up.

Study Design:

Case series; Level of evidence, 4.

Methods:

One hundred six men with autologous hamstring ACL reconstruction between the ages of 18 and 35 years were reviewed at 5 to 10 years after surgery. Excluded patients had contralateral ACL tear, revision reconstruction, or another injury impairing function. Fifty-five patients were eligible and available for follow-up. Independent variables included preinjury Tegner score, time interval from injury to surgery, smoking status, age, articular lesions, KT side-to-side difference, and pivot-shift grade. Main outcome measures were Tegner activity level, International Knee Documentation Committee (IKDC) subjective score, and Knee injury and Osteoarthritis Outcome Scale (KOOS) score at 5 to 10 years after surgery.

Results:

Greater Tegner activity level at follow-up was associated in a regression model with greater preinjury Tegner activity level (correlation coefficient, 0.423; P = .01), lower KT difference (correlation coefficient, –0.278; P = .04), and negative pivot shift (correlation coefficient, –0.277; P = .05). Younger age at operation predicted return to greater Tegner activity level in a univariate analysis (correlation coefficient, –0.266; P = .05) but not in a regression model (not significant). Chondral lesions at surgery predicted lower IKDC subjective scores (71.4 ± 14.3 vs 84.1 ± 11.5; P < .01) and KOOS scores but did not affect maintenance of sports activities.

Conclusion:

At 5 to 10 years after autologous hamstring ACL reconstruction in young men, predictors of greater sports activity level are primarily high preinjury activity level and reestablishment of knee laxity. Younger age at operation and moderate chondral lesions have lower impact in this respect.

Outcome of Patellar Tendon Versus 4-Strand Hamstring Tendon Autografts for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis of Prospective Randomized Trials

PURPOSE

To compare clinical outcomes of anterior cruciate ligament (ACL) reconstruction and investigate whether the clinical results of 4-strand hamstring tendon (HT) reconstruction are still inferior to that of the patellar tendon (PT).

METHODS

We performed a comprehensive systematic review and meta-analysis of the English literature on PubMed, Scopus, Web of Science, and the Cochrane register for papers that compared clinical outcomes of PT versus HT for ACL reconstruction. Outcome measures analyzed included rate of rerupture, KT-1000, International Knee Documentation Committee grade, Lachman, pivot shift, Lysholm score, Tegner Activity Scale, anterior knee pain, and discomfort on kneeling.

RESULTS

We included 19 studies from an initial 1,168 abstracts for the systematic review, and, eventually, 19 studies were included in the meta-analysis. The study population consisted of a total of 1784 patients. The average follow-up duration was 58.8 months. We found significant differences in favor of the HT technique in the domains of anterior knee pain, kneeling pain, and restriction in the range of active extension ("extension deficit"). We found no differences between the PT and HT technique in terms of rerupture rate. There were no clinically significant differences for the outcomes of Lysholm score and Tegner Activity Scale as well as the KT-1000 side-to-side at maximum manual force.

CONCLUSIONS

Contemporary 4-strand HT ACL reconstruction is comparable with the PT technique in terms of clinical stability and postoperative functional status across most parameters studied. The HT technique carries lower risk of postoperative complications such as anterior knee pain, kneeling discomfort, and extension deficit. Primary ACL reconstruction using the 4-strand HT technique achieves clinical results that are comparable with the PT technique with significantly less postoperative complications.

LEVEL OF EVIDENCE

Level I, systemic review and meta-analysis of Level I 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.

Tibial fixation in anterior cruciate ligament reconstruction

OBJECTIVE

To determine whether supplementary tibial graft fixation with a staple is routinely necessary for anterior cruciate ligament (ACL) reconstructions.

METHODS

We retrospectively reviewed a series of consecutive patients who underwent ACL reconstruction at our institution from April 2012 to July 2013. Patients who fulfilled the inclusion and exclusion criteria were divided into two groups, of which one with tibial fixation of the graft with a biointerference screw alone (biointerference screw group) and the other with tibial fixation of the graft with a biointerference screw and supplementary extra tunnel staple fixation (biointerference screw and staple group). All the surgeries were performed by a single fellowship-trained sports surgeon, using a standardized transportal technique and rehabilitation protocol. Both well-matched groups were evaluated at 1-year follow-up objectively for ligament laxity using instrumented testing with KT-2000 arthrometer and clinical tests as well as subjectively with the validated International Knee Documentation Committee 2000 (IKDC) and Lysholm knee score. All complications were reported.

RESULTS

A total of 64 patients (31 in the only biointerference screw group and 33 in the biointerference screw and staple group) were included in the study. At 1 year, there was no significant difference in the objective and subjective outcome assessments between the two groups. However, four patients from the group with supplementary staple experienced symptomatic hardware on kneeling of which two necessitated removal of hardware.

CONCLUSION

Our study showed that supplementary tibial graft fixation with a staple is not routinely necessary for ACL reconstructions. It confers no additional benefits when compared with the use of biointerference screw alone for tibial graft fixation but may increase the risks of symptomatic hardware.

The Cost-Effectiveness of Anterior Cruciate Ligament Reconstruction in Competitive Athletes

BACKGROUND

Competitive athletes value the ability to return to competitive play after the treatment of anterior cruciate ligament (ACL) injuries. ACL reconstruction has high success rates for return to play, but some studies indicate that patients may do well with nonoperative physical therapy treatment.

PURPOSE

To evaluate the cost-effectiveness of the treatment of acute ACL tears with either initial surgical reconstruction or physical therapy in competitive athletes.

STUDY DESIGN

Economic and decision analysis; Level of evidence, 2.

METHODS

The incremental cost, incremental effectiveness, and incremental cost-effectiveness ratio (ICER) of ACL reconstruction compared with physical therapy were calculated from a cost-effectiveness analysis of ACL reconstruction compared with physical therapy for the initial management of acute ACL injuries in competitive athletes. The ACL reconstruction strategy and the physical therapy strategy were represented as Markov models. Costs and quality-adjusted life-years (QALYs) were evaluated over a 6-year time horizon and were analyzed from a societal perspective. Quality of life and probabilities of clinical outcomes were obtained from the peer-reviewed literature, and costs were compiled from a large academic hospital in the United States. One-way, 2-way, and probabilistic sensitivity analyses were used to assess the effect of uncertainty in variables on the ICER of ACL reconstruction.

RESULTS

The ICER of ACL reconstruction compared with physical therapy was $22,702 per QALY gained. The ICER was most sensitive to the quality of life of returning to play or not returning to play, costs, and duration of follow-up but relatively insensitive to the rates and costs of complications, probabilities of return to play for both operative and nonoperative treatments, and discount rate.

CONCLUSION

ACL reconstruction is a cost-effective strategy for competitive athletes with an ACL injury.

Results After Anterior Cruciate Ligament Reconstruction in Patients Older Than 40 Years: How Do They Compare With Younger Patients? A Systematic Review and Comparison With Younger Populations

Context:

Anterior cruciate ligament (ACL) reconstruction in older patients is a controversial topic among orthopaedic surgeons.

Objective:

To determine the outcomes, failure, and morbidity associated with ACL reconstruction in patients older than 40 years and to compare it with nonoperative treatment as well as results of ACL reconstruction in a younger patient population.

Data Sources:

A systematic review of the literature from 1970 to 2015 was conducted utilizing MEDLINE, CINAHL, and the Cochrane Central Register databases using PRISMA guidelines.

Study Selection:

Inclusion criteria were studies with longer than 2-year follow-up of primary ACL reconstruction and minimum age of patients older than 40 years, inclusive of any graft type or source and of any concomitant meniscal pathology.

Study Design:

Systematic review.

Level of Evidence:

Level 4.

Data Extraction:

Two independent reviewers collected demographic, preoperative, intraoperative, and postoperative data.

Results:

Twelve studies with a total of 452 patients were included. The mean patient age was 47.8 years (range, 40-66 years) with a mean follow-up of 53.3 months (minimum, 24 months). Lysholm scores improved from 53.9 to 90.5 in the 11 operative studies. The only nonoperative study reported a mean Lysholm score of 82 after rehabilitation. International Knee Documentation Committee (IKDC) scores of A or B were found in 81%. Tegner activity scores averaged 4.7 preinjury, fell to 2.9 preoperatively, and returned to 4.7 postoperatively. The reported failure rate was 2.3%. There were few complications, and failure rate was similar in younger patients.

Conclusion:

The data confirm that ACL reconstruction can be recommended to patients older than 40 years who wish to maintain an active lifestyle or have symptomatic instability with daily activities. Patient-based outcomes scores were better in the operative studies compared with the single nonoperative study in this patient population.

Do graft diameter or patient age influence the results of ACL reconstruction?

PURPOSE

Hamstring tendons are commonly used as a graft source for ACL reconstruction. This study seeks to determine whether either the diameter of the tendon graft or the age of the patient influences the outcome of the ACL reconstruction when measured using a standard, previously validated laxity measurement device.

METHODS

This is a retrospective study of 88 patients who underwent ACL reconstruction with a short, quadrupled tendon technique, using the semitendinosus ± gracilis tendons. Patients included in this study were sequential, unilateral, complete ACL ruptures. The patients were followed for a minimum of 1 year postoperatively, with a mean follow-up of 26 months. Patients were divided into three groups according to the diameter (Ø) of the graft: group 1 (32 patients): 8 mm ≤ Ø ≤ 9 mm; group 2 (28 patients): 9 mm < Ø ≤ 10 mm; and group 3 (28 patients): Ø > 10 mm. Three groups with differential laxity at 134 N (Δ134 = healthy side vs. operated side) measured with the laximeter GNRB(®) were compared. The risk of residual laxity (OR) between the three groups taking age, gender, BMI and meniscus status into account was calculated. A side-to-side laxity >3 mm was considered as a residual laxity.

RESULTS

The mean patient age at the time of reconstruction was 29.4 years. The three groups were comparable. Postoperative Δ134 was 1.50 ± 1.3, 1.59 ± 1.5 and 2 ± 1.7 mm for groups 1 through 3, respectively. Δ134 > 3 mm was observed in three patients in group 1, four patients in group 2 and nine patients in group 3. As compared to group 1, OR was 1.46 (95 % CI 0.35-6.05) and 3.31 (95 % CI 0.89-12.34) in groups 2 and 3, respectively. Adjustment for age, gender, BMI and meniscus did not change the estimates [OR 1.44 (95 % CI 0.34-6.16) and 3.92 (95 % CI 1-15.37)] in groups 2 and 3, respectively. Patients younger than 20 had a significantly higher average postoperative laximetry (2.4 ± 1.5 mm) compared to those aged 20 years and over (1.5 ± 1.5 mm) (p = 0.03), regardless of the diameter of the graft.

CONCLUSION

The diameter of the graft between 8 and 10 mm does not affect the laximetric results of an ACL reconstruction. Therefore, there does not appear to be a benefit to harvesting and adding further tissue to increase the diameter of the graft above 10 mm. Patients younger than 20 represent a population at risk of graft elongation. In these patients at risk, postoperative management needs to be modified (delayed weight bearing, articulated splinting, slower rehabilitation) in the first months.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.

The Effect of Autologous Hamstring Graft Diameter on the Likelihood for Revision of Anterior Cruciate Ligament Reconstruction

BACKGROUND

Hamstring autografts for anterior cruciate ligament (ACL) reconstruction (ACLR) have become popular in the past 2 decades; however, it is difficult to predict the diameter of the harvested tendons before surgery. Previous biomechanical studies have suggested that a smaller graft diameter leads to a lower load to failure, but clinical studies looking at various predictors for failure, including graft size, have been inconclusive.

PURPOSE

To evaluate the relationship of hamstring graft diameter to ACL revision within a large cohort of patients, while controlling for sex, age, body mass index (BMI), and femoral and tibial fixation type.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A case-control study using patients registered in an ACLR registry was conducted. Revision was used as a marker for graft failure. A case was defined as a patient who underwent primary ACLR with a hamstring autograft that was revised during the study period (April 2006 to September 2012). Three controls, defined as patients who underwent primary ACLR with a hamstring autograft that was not revised, were matched to each of the cases according to age, sex, BMI, and femoral and tibial fixation type. Descriptive characteristics were employed, and conditional logistic regression was conducted to produce estimates of odds ratios and 95% CIs.

RESULTS

A total of 124 cases and 367 controls were identified. There were no significant differences between cases and controls in the distribution of sex (52.4% male vs 52.9% male, respectively; P = .932), median age (17.6 years [interquartile range (IQR), 15.9-20.4] vs 17.6 years [IQR, 15.9-20.4], respectively; P = .999), median BMI (23.4 kg/m(2) [IQR, 21.5-26.4] vs 23.4 kg/m(2) [IQR, 21.6-25.8], respectively; P = .954), femoral fixation (P = .459), and tibial fixation (P = .766). The mean (±SD) graft diameter was 7.9 ± 0.75 mm in the cases and 8.1 ± 0.73 mm in the controls. The likelihood of a patient needing revision ACLR in the study cohort was 0.82 times lower (95% CI, 0.68-0.98) for every 0.5-mm increase in the graft diameter from 7.0 to 9.0 mm.

CONCLUSION

In this study, within the range of 7.0 to 9.0 mm, there was a 0.82 times lower likelihood of being a revision case with every 0.5-mm incremental increase in graft diameter.

Comparison of Graft Failure Rate Between Autografts Placed via an Anatomic Anterior Cruciate Ligament Reconstruction Technique: A Systematic Review, Meta-analysis, and Meta-regression

BACKGROUND

Recent data from the Danish anterior cruciate ligament (ACL) registry demonstrated increased reoperation rates for hamstring tendon autografts when an anatomic ACL reconstruction is performed. This is consistent with reports of greater time needed for hamstring tendon autografts to mature compared with other autografts.

PURPOSE

To review the literature comparing graft failure rate between patellar and hamstring tendon autografts placed anatomically and to determine if there are differences in return to preinjury activity levels between autografts.

STUDY DESIGN

Systematic review with meta-analysis and meta-regression.

METHODS

The PubMed, MEDLINE, SPORTDiscus, and CINAHL databases were used to identify studies published from January 1, 2000, through March 7, 2014. To compare postoperative outcomes between patellar tendon and hamstring tendon autografts, summary event rates for graft failure and return to preinjury activity level were calculated. A meta-analysis was performed to calculate a summary odds ratio (OR) for graft failure between autografts using the studies that directly compared the 2 autografts. Meta-regression analyses were performed to assess the influence of postoperative follow-up time on graft failure rate.

RESULTS

A total of 28 studies reported graft failures for patellar tendon (6 studies) and hamstring tendon (26 studies) autografts used with anatomic ACL reconstruction; 4 of the 28 were comparison studies. Graft failure rate was not significantly different between patellar tendon (7.0% [95% CI, 4.6%-10.5%]) and hamstring tendon autografts (3.9% [95% CI, 2.7%-5.6%]). The odds of graft failure were slightly higher for hamstring tendon autografts (OR, 1.21 [95% CI, 0.63-2.33]), but this difference was not significant (P = .57). The rate of patients returning to preinjury activity levels was not significantly different between patellar (n = 1 study; 58.1% [95% CI, 40.4%-73.9%]) and hamstring tendon autografts (n = 5 studies; 75.6% [95% CI, 43.7%-92.5%]). Overall graft failure rate was positively associated with postoperative follow-up time, but this effect was only significant with hamstring tendon autografts (P < .05).

CONCLUSION

Differences in graft failure rate between patellar tendon and hamstring tendon autografts were not significant. Although follow-up time was only found to have a significant influence on hamstring tendon graft failure rates, this was likely due to the smaller sample of studies assessing patellar tendon graft failures. Differences in return to preinjury activity levels could not be determined due to the lack of studies assessing that outcome. Both patellar and hamstring tendon autografts demonstrate a low risk of failure and moderately high return to activity level after anatomic ACL reconstruction.

Prediction of semitendinosus-gracilis graft diameter in children and adolescents using anthropometric measures

PURPOSE

The aim of this study was to evaluate whether the anthropometric and demographic measures of patients under 18 years can be used to predict the diameter of STG autograft in ACL reconstruction surgery.

METHODS

Retrospective series of 169 patients under 18 years (112 men, 57 women, average age 15.8 years) underwent ACL reconstruction surgery with STG autograft. We recorded anthropometric measures (weight, height and BMI), demographics (age and gender) and autograft diameter used. Correlation coefficients, linear regression and unpaired t test were used to determine the relationship between anthropometric/demographic variables and the diameter of the graft. p values <0.05 were considered statistically significant.

RESULTS

Correlation analysis showed a significant positive relation between height and graft diameter (r = 0.483, p < 0.0001) as well as between weight and graft diameter (r = 0.248, p = 0.001). However, age and BMI did not correlate with graft thickness (r = 0.098 and p = 0.203, r = 0.009 and p = 0.905, respectively). The mean graft diameter in men was 8.2 (range 6-10) and 7.5 in women (range 6-9), a difference that was statistically significant (p < 0.001).

CONCLUSIONS

Prediction of the STG graft diameter according to the height of the patient is an easy and reliable method in children and adolescents. These data may provide relevant preoperative information about the need of an alternative graft source and can be useful when counselling patients.

LEVEL OF EVIDENCE

IV.

Hydroxyapatite-doped polycaprolactone nanofiber membrane improves tendon-bone interface healing for anterior cruciate ligament reconstruction

Hamstring tendon autograft is a routine graft for anterior cruciate ligament (ACL) reconstruction. However, ways of improving the healing between the tendon and bone is often overlooked in clinical practice. This issue can be addressed by using a biomimetic scaffold. Herein, a biomimetic nanofiber membrane of polycaprolactone/nanohydroxyapatite/collagen (PCL/nHAp/Col) is fabricated that mimics the composition of native bone tissue for promoting tendon–bone healing. This membrane has good cytocompatibility, allowing for osteoblast cell adhesion and growth and bone formation. As a result, MC3T3 cells reveal a higher mineralization level in PCL/nHAp/Col membrane compared with PCL membrane alone. Further in vivo studies in ACL reconstruction in a rabbit model shows that PCL/nHAp/Col-wrapped tendon may afford superior tissue integration to nonwrapped tendon in the interface between the tendon and host bone as well as improved mechanical strength. This study shows that PCL/nHAp/Col nanofiber membrane wrapping of autologous tendon is effective for improving tendon healing with host bone in ACL reconstruction.

Anterior knee symptoms after double-bundle ACL reconstruction with hamstring tendon autografts: an ultrasonographic and power Doppler investigation

PURPOSE

Anterior knee pain related to the donor site is a frequent complication of anterior cruciate ligament reconstruction (ACLR) with bone-patellar tendon-bone autograft tissue. Even when hamstring tendon (HT) grafts are used instead, symptoms such as mild pain and discomfort can still occur. The purpose of this study was to elucidate the pathophysiology of anterior knee symptoms after ACLR with HT autografts.

METHODS

Fifty-seven patients (22 men and 35 women; mean age, 24.7 years) who underwent anatomic double-bundle ACLR with HT autografts were examined 6 months post-operatively. The presence of anterior knee symptoms, anterior knee laxity, range of motion, and muscle strength were assessed. Changes in patellar tendon and infrapatellar fat pad (IFP) morphology and blood flow were also evaluated using ultrasound. Potential variables affecting the presence of anterior knee symptoms were subjected to univariate analysis and multivariate logistic regression analysis to identify independent risk factors.

RESULTS

Six months post-operatively, the total incidence of anterior knee symptoms was 56.1 % (32/57). According to univariate analysis, age, quadriceps strength, and increased blood flow in the IFP were significantly associated with the presence of anterior knee symptoms. Multivariate logistic regression analysis revealed that increased blood flow in the IFP was an independent factor for the presence of anterior knee symptoms (odds ratio 5.0; 95 % confidence interval 1.3-19.9). There were no significant findings inside the patellar tendon.

CONCLUSIONS

Increased blood flow in the IFP was identified as an independent factor for the presence of anterior knee symptoms 6 months after ACLR with HT autografts. The ultrasound evaluation can help to define precisely the origin of anterior knee symptoms after ACLR with HT autografts.

LEVEL OF EVIDENCE

Case series with no comparison groups, Level IV.

Ligamentization of Autogenous Hamstring Grafts After Anterior Cruciate Ligament Reconstruction: Midterm Versus Long-term Results

BACKGROUND

In previous studies, unimodal, small-diameter collagen fibrils have been commonly observed as the final collagen ultrastructure of the implanted grafts used in anterior cruciate ligament (ACL) reconstruction. However, the native ACL and hamstring tendon show bimodal collagen fibril distribution, consisting of both large- and small-diameter collagen fibrils.

HYPOTHESIS

Bimodal collagen fibril distribution of the graft is a common phenomenon after ACL reconstruction with hamstring tendon grafts and is time dependent.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 52 patients who underwent double-bundle ACL reconstruction using autogenous hamstring tendons and who also underwent second-look arthroscopic surgery were enrolled. The patients were divided into 2 groups according to the time interval between the 2 operations: the midterm group (27 patients), with a 13- to 30-month time interval between operations, and the long-term group (25 patients) with a 31- to 62-month interval. During the second-look arthroscopic procedures, ACL graft biopsies were performed. Normal ACL tissues were harvested from 9 patients who underwent total knee replacement, and biopsy specimens of the to-be-grafted semitendinosus tendon tissues were also harvested from another 9 patients who underwent ACL reconstruction with hamstring tendons, which were designated as normal controls. Graft vascularity, cellularity, metaplasia, cellular metabolism, and collagen fibril distribution were analyzed.

RESULTS

Large-diameter (>100 nm) collagen fibrils were detected in 81.5% of the specimens in the midterm group and in 68.0% of the specimens in the long-term group. A typical bimodal distribution mode was observed in 62.6% of the specimens in the midterm group and in 52.0% of the specimens in the long-term group. There was no significant difference between groups with respect to the presence of large-diameter collagen fibrils, bimodal distribution, graft vascularity, cellularity, metaplasia, or cellular metabolic status.

CONCLUSION

Graft ultrastructural maturation, characterized by large-diameter collagen fibrils and a bimodal collagen fibril distribution, is a common phenomenon and is not time dependent in the midterm to long term.

CLINICAL RELEVANCE

After hamstring tendon ACL reconstruction, the implanted grafts can transform into ACL-like tissue with a similar ultrastructure and metabolism, implying their usefulness as grafts.

Anterior Cruciate Ligament Reconstruction Using a Bone-Patellar Tendon-Bone Autograft to Avoid Harvest-Site Morbidity in Knee Arthroscopy

Although anterior cruciate ligament reconstruction using a bone-patellar tendon-bone (BPTB) autograft has many advantages (e.g., high strength and solid fixation), there are also several complications (e.g., anterior knee pain or kneeling pain) due to harvest-site morbidity associated with the use of this graft type compared with the use of hamstring tendon. Therefore the ultimate goal of anterior cruciate ligament reconstruction using a BPTB graft is to minimize harvest-site morbidity. We have used a technique for harvesting central-third BPTB grafts that involves only a 3-cm-long, longitudinal, curved incision in the medial tibial tuberosity for both graft harvesting and fixation. The purpose of this report is to describe the technique, which can avoid the harvest-site morbidities associated with BPTB autografts during knee arthroscopy. We believe that this less invasive reconstruction may reduce the harvest-site morbidities associated with BPTB grafts because it allows for BPTB graft harvesting without incising the synovial bursa or paratenon and mitigates scarring and adhesion formation.

Dynamic intraligamentary stabilization and primary repair: a new concept for the treatment of knee dislocation

BACKGROUND

Traumatic knee dislocation represents a rare but devastating injury. Several controversies persist regarding type of treatment, surgical timing, graft selection, repair versus reconstruction of the medial and lateral structures, surgical techniques and postoperative rehabilitation. A new technique for primary ACL stabilization, dynamic intaligamentary stabilization (DIS) was developed at the authors' institution. The purpose of this study was to analyze the clinical and radiological outcomes of surgically treated traumatic knee dislocations by means of the DIS technique for the ACL, primary suturing for PCL, MCL and LCL.

METHODS

Between 2009 and 2012, 35 patients treated surgically for traumatic knee dislocation with primary anterior cruciate ligament (ACL) reconstruction with DIS, suturing of the posterior cruciate ligament (PCL) and primary complete repair of collaterals, were evaluated clinically (IKDC score, SF12 health survey, Lysholm score, Tegner score) and radiologically with a mean follow up of 2.2 years (range 1.00-3.50 years) years. Instrumented anterior-posterior translation was measured (KT-2000).

RESULTS

Anterior/posterior translation (KT-2000) for the healthy and injured limb was 4.8mm (range 3-8mm) and 7.3mm (range 5-10) (89N) respectively. Valgus and varus stress testing in 30° flexion was normal in 26 (75%) and 29 (83%) patients, respectively. The IKDC score was B in 29 (83%) and C in 6 (17%) patients, while the mean Tegner score was 6 (range 4-8). The mean Lysholm score was 90.83 (range 81-95) and mean SF-12 physical and mental scores were 54.1 (range 45-60) and 51.0 (range 39-62) respectively. In 2 patients, a secondary operation was performed.

CONCLUSIONS

Early, one stage reconstruction with DIS can achieve good functional results and patient satisfaction with overall restoration of sports and working capacity without graft requirements.

A meta-analysis of bone-patellar tendon-bone autograft versus four-strand hamstring tendon autograft for anterior cruciate ligament reconstruction

BACKGROUND

There is a lack of comprehensive studies comparing the clinical outcome of anterior cruciate ligament (ACL) reconstruction with either a bone-patellar tendon-bone (BPTB) or four-strand hamstring tendon (4SHT) autografts. The optimal choice of graft for anterior cruciate ligament reconstruction remains controversial.

PURPOSE

The objective of this study was to evaluate the effectiveness of BPTB autografts versus 4SHT autografts for the reconstruction of ACL.

METHODS

A systematical search of literature was performed in Pubmed, Embase, and the Cochrane library to identify published clinical prospective studies relevant to ACL reconstruction comparing BPTB and 4SHT autografts. The results of the eligible studies were analysed in terms of instrumented laxity measurements, Lachman test, pivot shift test, objective International Knee Documentation Committee (IKDC) scores, return to preinjury activity level, and morbidity of graft failure, anterior knee pain, kneeling pain, extension deficit, and flexion deficit. Study quality was assessed by using the Jadad scale for randomized clinical trial (RCT) and the Newcastle-Ottawa Scale (NOS) for prospective cohort study (PCS). Two reviewers independently assessed each study for quality and extracted data. Subgroup analysis of the primary outcomes was conducted according to the type of study design (RCT or PCS).

RESULTS

Twenty-two studies, with 931 patients in the BPTB group and 999 patients in the 4SHT group, met the inclusion criteria. Fourteen studies were randomized controlled trials, and eight were prospective cohort studies. The results of the meta-analysis showed that there were no significant differences between BPTB and 4SHT in terms of instrumented laxity measurements (P=0.06), Lachman test (P=0.58), objective IKDC scores (P=0.31), graft failure (P=0.45), extension deficit (P=0.06) and flexion deficit (P=0.63). However, outcomes in favour of BPTB were found in terms of pivot shift test (P=0.01) and return to preinjury activity level (P=0.03); outcome measures that favours 4SHT included anterior knee pain (P<0.01) and kneeling pain (P<0.01). These findings were still robust during the sensitivity analysis. Results from subgroup analysis of the primary outcomes were consistent with the overall analysis.

CONCLUSION

Based on the results above, ACL reconstruction with BPTB autografts might be superior in resuming rotation stability of the knee joint and allow patients to return to higher levels of activity in comparison with 4SHT autografts. Whereas, postoperative complications of the knee joint were lower for 4SHT autografts than for BPTB autografts. There was insufficient evidence to identify which of the two types of grafts was significantly better for ACL reconstruction considering the limitations of this study. More high-quality randomized controlled trials with strictly specified inclusion criteria are highly required before drawing a reliable conclusion.

Myth busters: an AOA symposium: AOA critical issues

One of the goals of the annual American Orthopaedic Association (AOA) meeting is to address controversy, both in leadership and clinical practice. A panel of experts in their respective fields presented the background and literature behind three "myths" in orthopaedic management and made conclusions as to their validity. First, Dr. Kocher took on the myth of prophylactic pinning on the contralateral "normal" side for a patient with a slipped capital femoral epiphysis. Second, Dr. Probe evaluated the myth that all intertrochanteric fractures are best treated with intramedullary devices. Last, Dr. Foster and Dr. Silvestri tackled the myth that autograft is always the best choice for anterior cruciate ligament (ACL) reconstruction. All three of these topics are subjects of current debate. The panel's careful examination of the available data along with their expertise in the management of these problems is presented in this thought-provoking JBJS Critical Issues article.