Preserved insertions of the semitendinosus and gracilis tendons (STG) in ACL reconstruction: a new surgical technique with preliminary results

Quantitative MRI Biomarkers to Predict Risk of Reinjury Within 2 Years After Bridge-Enhanced ACL Restoration

BACKGROUND

Quantitative magnetic resonance imaging (qMRI) methods were developed to establish the integrity of healing anterior cruciate ligaments (ACLs) and grafts. Whether qMRI variables predict risk of reinjury is unknown.

PURPOSE

To determine if qMRI measures at 6 to 9 months after bridge-enhanced ACL restoration (BEAR) can predict the risk of revision surgery within 2 years of the index procedure.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Originally, 124 patients underwent ACL restoration as part of the BEAR I, BEAR II, and BEAR III prospective trials and had consented to undergo an MRI of the surgical knee 6 to 9 months after surgery. Only 1 participant was lost to follow-up, and 4 did not undergo MRI, leaving a total of 119 patients for this study. qMRI techniques were used to determine the mean cross-sectional area; normalized signal intensity; and a qMRI-based predicted failure load, which was calculated using a prespecified equation based on cross-sectional area and normalized signal intensity. Patient-reported outcomes (International Knee Documentation Committee subjective score), clinical measures (hamstring strength, quadriceps strength, and side-to-side knee laxity), and functional outcomes (single-leg hop) were also measured at 6 to 9 months after surgery. Univariate and multivariable analyses were performed to determine the odds ratios (ORs) for revision surgery based on the qMRI and non-imaging variables. Patient age and medial posterior tibial slope values were included as covariates.

RESULTS

In total, 119 patients (97%), with a median age of 17.6 years, underwent MRI between 6 and 9 months postoperatively. Sixteen of 119 patients (13%) required revision ACL surgery. In univariate analyses, higher International Knee Documentation Committee subjective score at 6 to 9 months postoperatively (OR = 1.66 per 10-point increase; P = .035) and lower qMRI-based predicted failure load (OR = 0.66 per 100-N increase; P = .014) were associated with increased risk of revision surgery. In the multivariable model, when adjusted for age and posterior tibial slope, the qMRI-based predicted failure load was the only significant predictor of revision surgery (OR = 0.71 per 100 N; P = .044).

CONCLUSION

Quantitative MRI-based predicted failure load of the healing ACL was a significant predictor of the risk of revision within 2 years after BEAR surgery. The current findings highlight the potential utility of early qMRI in the postoperative management of patients undergoing the BEAR procedure.

Properties of tests for knee joint threshold to detect passive motion following anterior cruciate ligament injury: a systematic review and meta-analysis

BACKGROUND

Threshold to detect passive motion (TTDPM) tests of the knee joint are commonly implemented among individuals with anterior cruciate ligament (ACL) injury to assess proprioceptive acuity. Their psychometric properties (PMPs), i.e. reliability, validity and responsiveness, are however unclear. This systematic review aimed to establish the PMPs of existing knee joint TTDPM tests among individuals with ACL injury.

METHODS

The databases PubMed, AMED, CINAHL, SPORTDiscus, Web of Science, Scopus, CENTRAL and ProQuest were searched to identify studies that assessed the properties of knee joint TTDPM tests in individuals with ACL injury. The risk of bias for each included study was assessed at the outcome level for each test. Overall quality and levels of evidence for each property were rated according to established criteria. Meta-analyses with mean differences were conducted using random-effects models when adequate data were available.

RESULTS

Fifty-one studies covering 108 TTDPM tests and 1632 individuals with unilateral ACL injury were included. A moderate-to-strong level of evidence indicated insufficient quality for all of the following: convergent validity, known-groups validity, discriminative validity, responsiveness between subgroups, and responsiveness to intervention. Subgroup meta-analyses for known-groups validity did however find that a starting angle of 15° resulted in significantly worse TTDPM for knees with ACL injury compared to those of asymptomatic persons (mean difference 0.28°; 95% CI 0.03 to 0.53; P = 0.03), albeit based on only three studies. Due to the lack of evidence, it was not possible to estimate the quality of reliability, measurement error, and criterion validity, nor responsiveness from a criterion and construct approach.

CONCLUSIONS

Among persons with ACL injury, existing tests of knee joint TTDPM lack either sufficient quality or evidence for their reliability, validity and responsiveness. Significantly worse thresholds for ACL-injured knees compared to those of asymptomatic controls from a 15° starting angle and trends towards significance for some validity measures nevertheless encourage the development of standardised tests. Further research investigating the influence of modifiable test components (e.g. starting angle and motion direction) on the PMPs of knee joint TTDPM tests following ACL injury is warranted.

Graft tunnel integration occurs early in the tibial tunnel compared with the femoral tunnel after anterior cruciate ligament reconstruction with preserved insertion hamstring tendon graft

BACKGROUND

Preservation of hamstring tendon insertion at the time of anterior cruciate ligament (ACL) reconstruction is a well-known technique; however, its effect on graft integration is not well studied. The present study was conducted to study the graft integration inside the tibial and femoral tunnels, respectively, after ACL reconstruction using hamstring tendon graft with preserved insertion.

METHODS

Twenty-five professional athletes who underwent ACL reconstruction using hamstring tendon graft with preserved tibia insertion were enrolled in the study. Functional outcomes were checked at final follow-up using Lysholm score and Tegner activity scale. Magnetic resonance imaging (MRI) was done at 8 months and 14 months follow-up to study the graft tunnel integration of the ACL graft at both tibial and femoral tunnels.

RESULTS

The mean Fibrous interzone (FI) score (tibial tunnel) decreased from 2.61 (1-5) at 8 months to 2.04 (1-4) at 14 months follow-up (p = 0.02). The mean FI score (femoral side) decreased from 3.04 (2-5) at 8 months to 2.57 (2-4) at 14 months (p = 0.02).

CONCLUSIONS

Graft integration occurs early in the tibial tunnel as compared with the femur tunnel with preserved insertion hamstring tendon autograft. Trial registration CTRI/2019/07/020320 [registered on 22/07/2019]; http://www.ctri.nic.in/Clinicaltrials/pdf_generate.php?trialid=33884&EncHid=&modid=&compid=%27,%2733884det%27.

Properties of Knee Joint Position Sense Tests for Anterior Cruciate Ligament Injury: A Systematic Review and Meta-analysis

Background:

Knee proprioception is believed to be deficient after anterior cruciate ligament (ACL) injury. Tests of joint position sense (JPS) are commonly used to assess knee proprioception, but their psychometric properties (PMPs) are largely unknown.

Purpose:

To evaluate the PMPs (reliability, validity, and responsiveness) of existing knee JPS tests targeting individuals with ACL injury.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

PubMed, Allied and Complementary Medicine, CINAHL, SPORTDiscus, Web of Science, Scopus, CENTRAL, and ProQuest databases were searched to identify studies that assessed PMPs of knee JPS tests in individuals with ACL injury. The risk of bias for each included study was assessed and rated at the outcome level for each knee JPS test. Overall quality and levels of evidence for each PMP were rated according to established criteria. Meta-analyses with mean differences were conducted using random effects models when adequate data were available.

Results:

Included were 80 studies covering 119 versions of knee JPS tests. Meta-analyses indicated sufficient quality for known-groups and discriminative validity (ACL-injured knees vs knees of asymptomatic controls and contralateral noninjured knees, respectively), owing to significantly greater absolute errors for ACL-injured knees based on a strong level of evidence. A meta-analysis showed insufficient quality for responsiveness, which was attributed to a lack of significant change over time after diverse interventions with a moderate level of evidence. Statistical heterogeneity (I² > 40%) was evident in the majority of meta-analyses. All remaining PMPs (reliability, measurement error, criterion validity, convergent validity, and other PMPs related to responsiveness) were assessed qualitatively, and they failed to achieve a sufficient quality rating. This was a result of either the study outcomes not agreeing with the statistical cutoff values/hypotheses or the level of evidence being rated as conflicting/unknown or based on only a single study.

Conclusion:

Knee JPS tests appear to have sufficient validity in differentiating ACL-injured knees from asymptomatic knees. Further evidence of high methodologic quality is required to ascertain the reliability, responsiveness, and other types of validity assessed here. We recommend investigations that compare the modifiable methodologic components of knee JPS tests on their PMPs to develop standardized evidence-based tests.

Low re-rupture rate with BPTB autograft and semitendinosus gracilis autograft with preserved insertions in ACL reconstruction surgery in sports persons

PURPOSE

To compare the results of bone-patellar tendon-bone graft (BPTB), semitendinosus-gracilis graft with preserved insertions (STGPI) and semitendinosus-gracilis-free graft (STGF) in terms of graft failure, objective mechanical stability, functional outcome, and return to sports in elite and recreational sports persons. It was hypothesized that the STGPI graft provided superior outcome as compared to the other two grafts.

METHODS

Two hundred and forty-nine elite and recreational players who underwent ACL reconstruction surgery, with BPTB graft (N = 80), STGPI graft (N = 85), and STGF graft (N = 84) with a minimum follow-up of 2 years, were assessed using clinical tests, knee arthrometer (KT 1000™), single-leg hop test, Lysholm knee score, Tegner's activity scale, and return to sports. Groups were matched in terms of age, gender, mode of injury, side involved, the level of sports, associated injuries, and mean follow-up.

RESULTS

The median age of the patients was 24 years (range 16-46 years), with 227 males and 22 females, with a mean follow-up of 61.8 ± 25.9 months. At the final follow-up, the mean side-to-side difference by KT 1000™ was significantly superior in BPTB group (1.4 ± 2.1 mm) as compared to STGPI (1.9 ± 2.0 mm) and STGF group (2.5 ± 2.0 mm) (p = 0.002). The mean Lysholm knee score, Limb symmetry index (LSI) using single-leg hop test and the mean difference in pre-injury and post-surgery level of Tegner's activity scale were not significantly different. The rate of graft failure was significantly higher in STGF group (7.1%) as compared to BPTB (1.2%) and STGPI (1.2%) groups (p = 0.043).

CONCLUSION

BPTB graft is a better graft in terms of mechanical stability than STGPI and STGF grafts. STGPI graft and BPTB graft are superior to STGF graft in terms of graft failure rate. However, there is no statistically significant difference amongst the three grafts in terms of return to sports and clinical tests of instability. STGPI graft is another option in the clinical setting with low graft failure rate like that of BPTB graft and with the added advantage of not having significant donor site morbidity.

LEVEL OF EVIDENCE

III.

Outcome of Hamstring Autograft With Preserved Insertions Compared With Free Hamstring Autograft in Anterior Cruciate Ligament Surgery at 2-Year Follow-up

PURPOSE

To compare mechanical stability, functional outcome, and level of return to sports activity in patients undergoing anterior cruciate ligament (ACL) reconstruction with a free hamstring graft versus a graft with preserved insertions at 2-year follow-up.

METHODS

This study was a prospective, single-blind (the evaluator was blinded), randomized trial of 110 adult professional athletes who were randomly allocated into 2 groups. Group 1 consisted of 55 patients who underwent ACL reconstruction with hamstring tendon autograft with preserved insertions (technique 1), and group 2 consisted of 55 patients who underwent ACL reconstruction with free hamstring tendon autograft (technique 2). An anteromedial portal was used for drilling of the femoral tunnel in all cases. Patients were assessed for a minimum follow-up of 2 years with clinical tests, the Activities of Daily Living Function Scale and Sports Function Scale (Cincinnati knee score), knee arthrometer (KT-1000) testing, and the Tegner activity scale.

RESULTS

The average age of the patients was 27.0 ± 7.5 years in group 1 and 27.2 ± 5.7 years in group 2. At 24 months, the mean side-to-side difference by KT-1000 testing was 1.4 in group 1 and 2.2 in group 2 (P < .0001); the mean Cincinnati knee score (Activities of Daily Living Function Scale and Sports Function Scale) was 418.5 (median, 420; range, 400-420) and 406.8 (median, 420; range, 350-420), respectively (P < .0001); and the mean difference between the preinjury and postsurgery Tegner level of sports activity was 0.3 and 1.08, respectively (P = .027).

CONCLUSIONS

Although ACL reconstruction using hamstring autograft with preserved insertions resulted in statistically superior anterior stability, a better functional outcome, and a closer return to the preinjury level of sports activity as compared with free autograft, no clinically significant difference was proved.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Delay in surgery predisposes to meniscal and chondral injuries in anterior cruciate ligament deficient knees

BACKGROUND

Despite improvements in instability after anterior cruciate ligament (ACL) reconstruction, associated intraarticular injuries remain a major cause of concern and important prognostic factor for long term results as it may lead to osteoarthritis. Delay in ACL reconstruction has been in variably linked to increase in these injuries but there is lack of consensus regarding optimal timing of reconstruction. The goal of this study was to investigate delay in surgery and other factors, associated with intraarticular injuries in ACL deficient knees.

MATERIALS AND METHODS

A total of 438 patients (42 females; 396 males) enrolled for this prospective observational study. The average age of patients was 26.43 (range 17-51 years) years with a mean surgical delay of 78.91 (range 1 week - 18 years) weeks after injury. We analyzed the factors of age, sex, surgical delay, instability, and level of activity for possible association with intraarticular injuries.

RESULTS

Medial meniscus injuries had a significant association with surgical delay (P = 0.000) after a delay of 6 months. Lateral meniscus injuries had a significant association with degree of instability (P = 0.001). Medial-sided articular injuries were significantly affected by age (0.005) with an odds ratio (OR) of 1.048 (95% confidence interval [CI] of 1.014-1.082) reflecting 4.8% rise in incidence with each year. Lateral-sided injuries were associated with female sex (P = 0.018) with OR of 2.846 (95% CI of 1.200-6.752). The level of activity failed to reveal any significant associations.

CONCLUSION

Surgical delay predicts an increase in medial meniscal and lateral articular injuries justifying early rather than delayed reconstruction in ACL deficient knees. Increasing age is positively related to intraarticular injuries while females are more susceptible to lateral articular injuries.

Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Autograft With Preserved Insertions

We present a technique for anterior cruciate ligament (ACL) reconstruction using hamstring tendon autograft with preserved tibial insertions. The tendons, harvested with an open-ended tendon stripper while their tibial insertions are preserved, are looped around to prepare a quadrupled graft. The femoral tunnel is drilled independently through a transportal technique, whereas the tibial tunnel is drilled in a standard manner. The length of the quadrupled graft and loop of the RetroButton is adjusted so that it matches the calculated length of both tunnels and the intra-articular part of the proposed ACL graft. After the RetroButton is flipped, the graft is manually tensioned with maximal stretch on the free end, which is then sutured to the other end with preserved insertions. We propose that preserving the insertions is more biological and may provide better proprioception. The technique eliminates the need for a tibial-side fixation device, thus reducing the cost of surgery. Furthermore, tibial-side fixation of the free graft is the weakest link in the overall stiffness of the reconstructed ACL, and this technique circumvents this problem. Postoperative mechanical stability and functional outcome with this technique need to be explored and compared with those of ACL reconstruction using free hamstring autograft.