Treatment of anterior cruciate ligament injuries with special reference to surgical technique and rehabilitation: an assessment of randomized controlled trials

LARS Artificial Ligament Versus ABC Purely Polyester Ligament for Anterior Cruciate Ligament Reconstruction

Background:

Graft choice for anterior cruciate ligament (ACL) reconstruction is of critical importance. Various grafts have been used so far, with autografts long considered the optimal solution for the treatment of ACL-deficient knees. Limited data are available on the long-term survivorship of synthetic grafts.

Purpose:

To compare the functional outcome and survivorship of ACL reconstructions performed using the LARS (ligament augmentation and reconstruction system) ligament and the ABC (active biosynthetic composite) purely polyester ligament.

Study Design:

Case series; Level of evidence, 4.

Methods:

The results of 72 patients who underwent primary arthroscopic ACL reconstruction with the LARS ligament and 31 cases with an ABC purely polyester ligament were reviewed. The mean follow-up periods for the LARS and ABC groups were 9.5 and 5.1 years, respectively. A survivorship analysis of the 2 synthetic grafts was performed using the Kaplan-Meier method with a log-rank test (Mantel-Cox, 95% CI). Lysholm, Tegner activity, Knee injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) scores as well as laxity measurements obtained using a KT-1000 arthrometer were recorded for all intact grafts, and a Mann-Whitney U test was used for comparison reasons.

Results:

The rupture rates for LARS and ABC grafts were 31% (95% CI, 20%-42%) and 42% (95% CI, 25%-59%), respectively. For intact grafts, the mean Lysholm score was good for both groups (90 for the LARS group and 89 for the ABC group), with the majority of patients returning to their preinjury level of activities, and the mean IKDC score was 90 for the LARS group and 86 for the ABC group.

Conclusion:

The rupture rates of both LARS and ABC grafts were both high. However, the LARS ligament provided significantly better survivorship compared with the ABC ligament at short- to midterm follow-up (95% CI).

Management of anterior cruciate ligament injury: pathophysiology and treatment

Anterior cruciate ligament injury, a common soft tissue injury of the knee joint, is increasing in incidence particularly in young active people. It causes instability of the knee that leads to meniscal tears, cartilage defects and early osteoarthritis. This review summarizes aspects of anterior cruciate ligament injury management.

A Systematic Summary of Systematic Reviews on the Topic of the Anterior Cruciate Ligament

BACKGROUND

There has been a substantial increase in the amount of systematic reviews and meta-analyses published on the anterior cruciate ligament (ACL).

PURPOSE

To quantify the number of systematic reviews and meta-analyses published on the ACL in the past decade and to provide an overall summary of this literature.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of all ACL-related systematic reviews and meta-analyses published between January 2004 and September 2014 was performed using PubMed, MEDLINE, and the Cochrane Database. Narrative reviews and non-English articles were excluded.

RESULTS

A total of 1031 articles were found, of which 240 met the inclusion criteria. Included articles were summarized and divided into 17 topics: anatomy, epidemiology, prevention, associated injuries, diagnosis, operative versus nonoperative management, graft choice, surgical technique, fixation methods, computer-assisted surgery, platelet-rich plasma, rehabilitation, return to play, outcomes assessment, arthritis, complications, and miscellaneous.

CONCLUSION

A summary of systematic reviews on the ACL can supply the surgeon with a single source for the most up-to-date synthesis of the literature.

Graft tensioning practices in anterior cruciate ligament reconstruction amongst orthopaedic surgeons in Australia: a national survey

PURPOSE

The application of graft tension during anterior cruciate ligament reconstruction is considered an important feature of ACLR. However, wide variation exists in relation to graft tensioning practice limiting the ability to determine the best approach. Thus, the primary aim of this study was to describe current clinical practice amongst Australian orthopaedic surgeons with respect to graft tensioning and explore influencing factors.

MATERIALS AND METHODS

A survey was developed to address the aims of the study and pilot testing was completed to confirm validity and reliability. The survey population was defined as Australian orthopaedic surgeons, associated with the Australian Orthopaedic Association sub-specialty of knee to target surgeons likely to perform ACLR. The final sampling frame consisted of 192 surgeons.

RESULTS

Manual tensioning was the most common method (80.5 %), with a maximum one-handed pull the most frequent description and estimated tension ranged between 41 and 60 N with the knee positioned near full extension. Surgeons using a tensioning device tended to use a higher tension (mean 81.85 N), with the knee positioned at 30° flexion (40 %). Sixteen percent reported individualising tension on viscoelasticity of the graft, graft diameter, patient anthropometry and age. Patient outcomes and available evidence were the primary factors influencing tensioning protocol.

CONCLUSION

Tensioning practices appear to consist of three main approaches, (1) manual tension using a sustained maximum one-handed pull, with tension estimated as 41-60 N, applied near full extension, (2) tensioning device, mean tension of 81.85 N, at 30° knee flexion, (3) individual approach based on size and viscoelastic properties of the graft, patient anthropometry, contralateral comparison to the other knee and age of the patient.

A Three-Dimensional Evaluation of EndoButton Displacement Direction After Anterior Cruciate Ligament Reconstruction in CT Image Using Tunnel Axis

The goal of this study was to propose a threedimensional evaluation of the EndoButton displacement direction after anterior cruciate ligament reconstruction in the multidetector-row computed tomography (MDCT) image by using the tunnel axis. The proposed method was applied experimentally to six subjects. The result of the simulated experiment revealed that the proposed method could analyze EndoButton displacement direction satisfactorily because the error was less than that of the MDCT image resolution. The clinical experiment results revealed displacement relative to the tunnel between time-zero and the followup point. We conclude that the proposed method can quantitatively evaluate the EndoButton displacement direction from the raw MDCT image after anterior cruciate ligament reconstruction; further, our findings suggest that the EndoButton was displaced relative to the tunnel between time-zero and the follow-up point.

Principles of postoperative anterior cruciate ligament rehabilitation

It is known that anterior cruciate ligament (ACL) reconstruction needs to be combined with detailed postoperative rehabilitation in order for patients to return to their pre-injury activity levels, and that the rehabilitation process is as important as the reconstruction surgery. Literature studies focus on how early in the postoperative ACL rehabilitation period rehabilitation modalities can be initiated. Despite the sheer number of studies on this topic, postoperative ACL rehabilitation protocols have not been standardized yet. Could common, “ossified” knowledge or modalities really prove themselves in the literature? Could questions such as “is postoperative brace use really necessary?”, “what are the benefits of early restoration of the range of motion (ROM)?”, “to what extent is neuromuscular electrical stimulation (NMES) effective in the protection from muscular atrophy?”, “how early can proprioception training and open chain exercises begin?”, “should strengthening training start in the immediate postoperative period?” be answered for sure? My aim is to review postoperative brace use, early ROM restoration, NMES, proprioception, open/closed chain exercises and early strengthening, which are common modalities in the very comprehensive theme of postoperative ACL rehabilitation, on the basis of several studies (Level of Evidence 1 and 2) and to present the commonly accepted ways they are presently used. Moreover, I have presented the objectives of postoperative ACL rehabilitation in tables and recent miscellaneous studies in the last chapter of the paper.

Surgical Predictors of Early Revision Surgery After Anterior Cruciate Ligament Reconstruction: Results From the Swedish National Knee Ligament Register on 13,102 Patients

BACKGROUND

An important objective of anterior cruciate ligament (ACL) registries is to detect and report early graft failure and revision surgery after ACL reconstruction.

PURPOSE

To investigate surgical variables and identify predictors of revision surgery after ACL reconstruction.

STUDY DESIGN

Prospective cohort study; Level of evidence, 2.

METHODS

This prospective cohort study was based on data from the Swedish National Knee Ligament Register during the years 2005 through 2011. Eight surgical variables were investigated: graft selection, graft width, single-bundle or double-bundle techniques, femoral graft fixation, tibial graft fixation, injury-to-surgery interval, injuries to menisci, and injuries to cartilage. The primary endpoint was the 2-year incidence of revision surgery. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated and adjusted for confounders by use of multivariate statistics.

RESULTS

A total of 13,102 patients were included (5541 women [42%] and 7561 men [58%]; P < .001). Hamstring tendon autografts accounted for 90% (11,764 patients) of all reconstructions, of which 96% were performed with a single-bundle technique (11,339 patients). Patellar tendon autografts accounted for the remaining 10% (1338 patients). At index reconstruction, observed injuries to menisci and cartilage were common (40% and 28%, respectively). The overall 2-year incidence of revision surgery was 1.60% (women, 1.57%; men, 1.63%; P = .854). Patients with metal interference screw fixation of a semitendinosus tendon autograft on the tibia had a significantly reduced risk of early revision surgery (RR = 0.32; 95% CI, 0.12-0.90; P = .031).

CONCLUSION

Metal interference screw fixation of a semitendinosus tendon autograft on the tibia was an independent predictor of significantly lower 2-year incidence of revision surgery. Graft selection, graft width, a single-bundle or a double-bundle technique, femoral graft fixation, the injury-to-surgery interval, and meniscus injury were not predictors of early revision surgery.

Functional bracing of ACL injuries: current state and future directions

PURPOSE

Functional braces are commonly prescribed to treat anterior cruciate ligament (ACL) injury. The results of the existing literature on functional brace use are mixed. The purpose of this study was to evaluate the history and current state of functional ACL bracing and to identify design criteria that could improve upon current bracing technologies.

METHODS

A literature search was performed through the PubMed MEDLINE database in April 2013 for the keywords "anterior cruciate ligament" and "brace". Articles published between January 1, 1980, and April 4, 2013, were retrieved and reviewed. Current functional braces used to treat ACL injury were identified. The function of the native ACL was carefully studied to identify design requirements that could improve upon current bracing technologies.

RESULTS

Biomechanical evaluations of functional brace effects at time zero have been mixed. Functional brace use reportedly does not improve long-term patient outcomes following ACL reconstruction, but has been shown to reduce subsequent injury rates while skiing in both ACL-deficient and reconstructed skiers. In situ force in the ACL varies with flexion angle and activity. Currently, no brace has been designed and validated to replicate the force-flexion behavior of the native ACL.

CONCLUSIONS

Biomechanical and clinical evidence suggests current functional bracing technologies do not sufficiently restore normal biomechanics to the ACL-deficient knee, protect the reconstructed ACL, and improve long-term patient outcomes. Further research into a functional brace designed to apply forces to the knee joint similar in magnitude to the native ACL should be pursued.

LEVEL OF EVIDENCE

III.

Evidence-based approach of treatment options for postoperative knee pain

Optimal pain management is critical after knee surgery to avoid adverse events and to improve surgical outcomes. Pain may affect surgical outcomes by contributing to limitations in range of motion, strength, and functional recovery. The causes of postoperative pain are multifactorial; therefore, an appropriate pain management strategy must take into account preoperative, intraoperative, and postoperative factors to create a comprehensive and individualized plan for the patient. Preoperative assessment includes management of patient expectations, recognition of conditions and early counseling for high-risk patients (ie, opioid dependence, psychiatric comorbidities), and use of preemptive analgesia techniques (ie, preoperative IV medications, peripheral nerve blocks, incisional field blocks). Intraoperative strategies include meticulous surgical technique, limiting the use of tourniquets (ie, duration and pressure), and using preventive analgesia methods (ie, postoperative field block, continuous nerve catheters, intra-articular injection). Postoperative analgesia may be facilitated by cryotherapy, early mobilization, bracing, and rehabilitation. Certain modalities (ie, continuous passive motion devices, transcutaneous electrical nerve stimulation units, iontophoresis) may be important adjuncts in the perioperative period as well. There may be an evolving role for alternative medicine strategies. Early recognition and treatment of exaggerated postoperative pain responses may mitigate the effects of complex regional pain syndrome or the development of chronic pain.

Brace or no-brace after ACL graft? Four-year results of a prospective clinical trial

PURPOSE

A controversial discussion is held on using stabilizing knee braces after anterior cruciate ligament (ACL) surgery. The current study investigated the influence of a stabilizing knee brace on results after ACL reconstruction using patellar tendon autografts.

METHODS

A prospective randomized study was started including 64 patients divided into two equal groups and treated with or without a stabilizing knee brace for 6 weeks post-operatively. A follow-up examination 4 years after operation comprised IKDC 2000, KT1000 measurement, a visual analogue pain scale (VAS; scores 0-10) and radiographic evaluation. The t test for independent and paired samples and the Pearson's Chi-square test were used for statistical analysis (p < 0.05). The primary endpoint was the difference in IKDC classification.

RESULTS

Eighty-one per cent of the patients were examined 4 years post-operatively. IKDC 2000 subjective (brace group 90.5 ± 8.9, braceless group 93.2 ± 6.1) and objective results (brace A 30%, B 56%, C 16%; braceless A 32%, B 48%, C 20%) and instrumental measurement of anteroposterior laxity with KT1000 (brace 0.6 ± 2.4 mm, braceless 1.8 ± 3.4 mm) showed no significant differences. VAS pain results were significantly better in the braceless group at 1.0 ± 1.2 versus 1.9 ± 1.4 under sports activity or heavy physical work (p = 0.015). There were no radiographic differences concerning osteoarthritic findings and tunnel widening between the groups.

CONCLUSION

Post-operative treatment with a stabilizing knee brace after ACL replacement showed no advantage over treatment without a brace at 4-year follow-up. The use of a knee-stabilizing brace after isolated ACL reconstruction with autologous patellar tendon graft is not recommended.

LEVEL OF EVIDENCE

II.

Metallic or bioabsorbable interference screw for graft fixation in anterior cruciate ligament (ACL) reconstruction?

BACKGROUND

Approximately 100,000 anterior cruciate ligament (ACL) reconstructions are performed in the USA each year. Interference screw fixation is considered the standard for rigid fixation of the graft and provides higher fixation strength compared with other devices such as staples or buttons. The present study summarizes the latest evidence comparing the effectiveness of the available classes of interference screws for fixation of ACL grafts.

SOURCES

A comprehensive search of the CINAHL, PubMed, Google Scholar, Embase Biomedical databases and the Cochrane Central Registry of Controlled Trials was performed in March 2013. Twelve studies met our inclusion criteria.

AREAS OF AGREEMENT

Most studies showed no intergroup difference in terms of outcomes measured with validated clinical scores such as IKDC (International Knee Documentation Committee), Lysholm score and Tegner activity level. There was no significant difference regarding range of motion. Knee stability as evaluated with pivot shift and KT arthrometer showed a significant difference only in one study, favouring metallic interference screws. Tunnel widening is much more evident and marked patients who underwent ACL reconstruction with bioabsorbable screws, with no influence on the final clinical results achieved. Complication rates between the two screw classes were similar. The average modified Coleman methodology score was 74.67. AREAS OF UNCERTAINTY/RESEARCH NEED: The data comparing the outcomes achieved by two different materials for fixation, bioabsorbable and metallic, to be used during single-bundle ACL reconstruction, showed no significant difference in the final patient outcomes, in terms of clinical scores, clinical evaluation and imaging.

Compliance of randomized controlled trials in trauma surgery with the CONSORT statement

BACKGROUND

Randomized controlled trials (RCTs) are the criterion standard for assessing new interventions. However, bias can result from poor reporting, which also makes critical appraisal and systematic review challenging. The Consolidated Standards of Reporting Trials (CONSORT) criteria for nonpharmacological trials published in 2008 provided a set of 23 mandatory items that should be reported in an RCT. This is the first study to assess the compliance of RCTs in trauma with the CONSORT criteria for nonpharmacological trials.

METHODS

The MEDLINE database was searched using the MeSH term wounds and injuries for English-language articles published between January 2009 and December 2011. Relevant articles were scored by two reviewers and compared against surrogate markers of article quality (such as journal impact factor).

RESULTS

Eighty-three articles were deemed suitable for inclusion. The mean CONSORT score was 11.2 of 23 items (49%; range, 3.38-18.17). Compliance was poorest for items relating to the adherence of care providers (0%), abstract (5%), and implementation of randomization (6%). Only 40% declared conflicts of interest, 73% declared permission from an ethics review committee, 43% declared sources of funding, and 10% stated a trial registry number. There was a significant correlation between the CONSORT score and the impact factor of the publishing journal (ρ = 0.37, p = 0.0006) but not for the number of patients or authors or single versus multicentre trials

CONCLUSION

The reporting quality of RCTs in trauma surgery needs improvement. We suggest ways by which this could be improved including the following: better education, awareness, and a cohesive strategy among all stakeholders and the hard wiring of compliance through electronic journal submission systems.

An Automatic Three-Dimensional Evaluation of Screw Placement After Anterior Cruciate Ligament Reconstruction Using MDCT Images

A metallic interference screw, which is a fixation device used in anterior cruciate ligament (ACL) reconstruction, is important for fixing the grafts to the tibia. Loosening of fixation sometimes happens because the screw is displaced time passes, which results in instability of the knee. It is therefore important to analyze screw displacement highly accurately. The purpose of this study is to propose an evaluation of screw displacement in MDCT imaging of the knee after ACL reconstruction. Clinical experiments used 22 MDCT images that are not displaced in the clinical sense. Results of simulation experiments show that error was 0.14 mm, which was less thanMDCT image resolution. This study concluded that the proposed method useful in evaluating two MDCT images at different time points.

Timing of surgery of the anterior cruciate ligament

PURPOSE

We aimed to perform a systematic review of the literature concerned with timing of surgery after anterior cruciate ligament injury.

METHODS

A systematic electronic search in Medline through PubMed, Embase, and the Cochrane Library was carried out in October 2011. All English-language randomized controlled clinical trials, prospective comparative cohort studies, and prognostic and diagnostic studies published from January 1995 to August 2011 were eligible for inclusion. All articles addressing timing of surgery were eligible for inclusion regardless of injury-to-surgery interval, graft type, surgical technique, or rehabilitation. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist guided the reporting and data abstraction. Methodologic quality of all included articles was carefully assessed.

RESULTS

We included 22 articles (3,583 patients) in the systematic review. Study design, research methodology, surgical technique, and outcome measurements differed greatly among included articles. The injury-to-surgery interval, classified as early and delayed, ranged from within 2 days to 7 months and 3 weeks to 24 years, respectively. Eight articles promoted early reconstruction, whereas the majority of articles found no difference in outcome between early and delayed surgery. Two articles were inconclusive.

CONCLUSIONS

There were few or no differences in subjective and objective outcomes related to timing of anterior cruciate ligament reconstruction.

LEVEL OF EVIDENCE

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

Anterior cruciate ligament deterioration correlates with patella osteoarthritis

PURPOSE

The correlation between anterior cruciate ligament (ACL) condition and patella osteoarthritic (OA) changes has not been well reported. The aim of this study was to reveal the correlation between ACL deterioration and the morphology of OA changes in the patella. The hypothesis was that significant correlation between ACL deterioration and patella OA morphology would be revealed in this study.

METHODS

Two hundred ninety-one cadaveric knees from 151 cadavers were included in this study with a median age of 83 years (54-98). Knees were opened with a sub-vastus approach and the ACL condition was classified as intact or deteriorated. Patella OA lesions were classified using Han's method: type 1, no or minimal lesion; type 2, medial facet lesion without involvement of the ridge; type 3, lateral facet lesion without involvement of the ridge; type 4, lesion involving the ridge only; type 5, medial facet lesion with involvement of the ridge; type 6, lateral facet lesion with involvement of the ridge; and type 7, global lesion. OA depth evaluation was performed following Outerbridge's classification. Statistical analysis of the collected data was performed using generalized estimating equations (GEE).

RESULTS

The ACL was intact in 277 knees and deteriorated in 14 knees. Patella OA lesions were observed as follows: type 1, 29%; type 2, 15%; type 3, 2%; type 4, 12%; type 5, 18%; type 6, 2%; and type 7, 22%. Outerbridge's classification of over grade 2 OA depth was observed in 73.5% of subjects. When patella OA was divided into types 1-4 and types 5-7, ACL deterioration was correlated with the occurrence of type 5-7 patella OA [OR 6.44, 95%CI 2.27-18.25, p = 0.000]. When patella OA was divided into types 1-6 and type 7, ACL deterioration was correlated with the occurrence of type 7 patella OA [OR 6.02, 95%CI 2.57-14.09, p = 0.000]. When patella OA depth was divided into grades 1-3 and grade 4, ACL deterioration was highly correlated with the occurrence of grade 4 patella OA [OR 9.31, 95%CI 2.96-29.33, p = 0.025].

CONCLUSION

ACL deterioration is a strong risk factor of wider and deeper OA changes in the patella. For clinical relevance, subjects with ACL tear should be aware of the progression of patella OA.

Reducing anterior tibial translation by applying functional electrical stimulation in dynamic knee extension exercises: quantitative results acquired via marker tracking

BACKGROUND

Pain that accompanies anterior cruciate ligament deficiency during dynamic knee extension exercises is usually caused by excessive anterior tibial translation, which can be restricted if the anterior cruciate ligament was intact.

METHODS

A functional electrical stimulator is incorporated with a training device to induce hamstring contractions during certain degrees of knee extension to replicate effects similar to those generated by an intact anterior cruciate ligament and to reduce anterior tibial translation. By using a camera that tracks markers placed on bony prominences of the femur and tibia, the anterior tibial translations corresponding to various settings were determined by customized image processing procedures.

FINDINGS

In the electrical stimulation sessions, the knee extensions with electrical stimulation feedback induced significantly (n=6, P<.05) less anterior tibial translation over the range of 20 to 50° when compared to those using the standard isokinetic shank restraint. Likewise, the knee extensions with an anti-shear device that blocks tibia displacement mechanically also induced significantly (n=6, P<.05) less anterior tibial translation, but over a different range of knee extension (30 to 70°).

INTERPRETATION

Despite the fact that both the electrical stimulator and the anti-shear device assisted in reducing anterior tibial translation, the tendency of the curves generated with the functional electrical stimulation was generally more similar to those generated when using the standard isokinetic shank restraint.

Applications of computer navigation in sports medicine knee surgery: an evidence-based review

Computer-assisted surgery (CAS) has been investigated in a number of sports medicine procedures in the knee. Current barriers to its widespread introduction include increased costs, duration, and invasiveness of surgery. Randomized trials on the use of CAS in anterior cruciate ligament reconstruction have failed to demonstrate a clinical benefit. Data on CAS use in high tibial osteotomy are more promising; however, long-term studies are lacking. CAS has a number of research applications in knee ligament surgery, and studies continue to explore its use in the treatment of osteochondral lesions. This article reviews the applications of CAS in sports medicine knee surgery and summarizes current literature on clinical outcomes.

A cross-sectional study comparing the rates of osteoarthritis, laxity, and quality of life in primary and revision anterior cruciate ligament reconstructions

PURPOSE

The purpose of this study was to assess the degree of osteoarthritis, degree of laxity, and quality-of-life (QOL) scores in primary and revision anterior cruciate ligament (ACL) reconstruction.

METHODS

This was a cross-sectional study; 25 patients who had undergone revision ACL reconstruction with allografts were identified and compared with 27 randomly selected primary ACL reconstruction patients operated on in the same hospital in the same period with the same technique. The main outcome measure was the International Knee Documentation Committee (IKDC) radiographic osteoarthritis sum score, and secondary outcome measures were Knee injury and Osteoarthritis Outcome Score, IKDC functional outcome measures, anterior laxity, and QOL at follow-up.

RESULTS

The median follow-up was 5.3 years for revision reconstruction patients and 5.1 years for primary reconstruction patients. Radiographic IKDC sum scores for osteoarthritis were found to be significantly worse in revision patients, with a median of 4, compared with primary patients, with a median of 1 (P = .016). Differences were found in meniscal injury (P = .02) and cartilage status (P < .001) before or at the index operation. Significantly worse outcomes were found in the following subscores of the Knee injury and Osteoarthritis Outcome Score: pain (median, 92 v 97; P = .032), symptom (median, 86 v 96; P = .015), activities of daily living (median, 94 v 100; P = .020), sport (median, 50 v 85; P = .006), and QOL (median, 56 v 81; P = .001). IKDC functional outcome measures were the same in both groups except for the pivot-shift test (P = .007). No differences were found in anterior drawer, Lachman, or KT-1000 arthrometer (MEDmetric, San Diego, CA) testing. Present-day health scores on the EQ-5D were worse for revision reconstruction patients (median, 70 v 80; P = .009).

CONCLUSIONS

Revision reconstruction patients have more signs of osteoarthritis and worse QOL than primary reconstruction patients, even though they have comparable IKDC success rates and KT-1000 arthrometer laxity test results.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Level of evidence in anterior cruciate ligament reconstruction research: a systematic review

BACKGROUND

There have been numerous studies on anterior cruciate ligament (ACL) reconstruction. Considering the vast number of studies, a quick assessment reveals rather few with a high level of evidence.

PURPOSE

The primary aim was to categorize the study type and level of evidence of studies on primary ACL reconstruction by applying the level of evidence rating system proposed by the Oxford Centre for Evidence-Based Medicine. The secondary aims were to correlate the level of evidence with the impact factor of the journal, to evaluate the level of evidence over time, and to evaluate the geographic distribution of the included studies.

STUDY DESIGN

Systematic review.

METHODS

An electronic search was performed using the databases PubMed, EMBASE, and Cochrane Library. Studies published from January 1995 to August 2011 were included. Therapeutic studies written in English that report on isolated primary ACL reconstruction with clinical outcome measurements related to the reconstruction were included. Categorization and implementation of the level of evidence were performed. Correlation between the level of evidence and the impact factor of the journal was analyzed together with linear regression models to reveal any significant trends over time.

RESULTS

A total of 7154 studies were analyzed, of which 1510 were included. Analysis of the study types revealed that case series (n = 494; 32.7%) was the most frequent study type. Randomized controlled trials represented 9.2% (n = 139) of the sample, whereas meta-analyses were rare. Single-bundle studies were the most common studies (n = 1333; 88.3%), followed by double-bundle (n = 98; 6.5%) and single- versus double-bundle (n = 79; 5.2%). The journals Arthroscopy, Knee Surgery Sports Traumatology Arthroscopy (KSSTA), and American Journal of Sports Medicine (AJSM) represented 43.5% (n = 657) of the included studies. Arthroscopy had the highest number of publications in general and in level 4 and 5 studies, whereas AJSM had the lowest number of the 3. AJSM had the highest number of level 1 and 2 studies in general. The mean level of evidence calculated without level 5 studies was 3.15 for Arthroscopy, 3.20 for KSSTA, and 2.9 for AJSM. There was a significant correlation (P < .05) between the impact factor of the journal and mean level of evidence of the journal and the proportion high level of evidence studies (levels 1 and 2). There was a significant (P < .05) trend toward higher mean level of evidence over time.

CONCLUSION

Most therapeutic studies on primary ACL reconstruction were of low level of evidence, and there was a positive correlation between the journal's impact factor and the mean level of evidence and the proportion of high level of evidence studies. There was significant trend toward higher mean level of evidence over time.

Long-term results of arthroscopically assisted anatomical single-bundle anterior cruciate ligament reconstruction using patellar tendon autograft: are there any predictors for the development of osteoarthritis?

PURPOSE

The primary purpose of our study was to analyse the long-term outcome of patients treated for anterior cruciate ligament (ACL) tears by anatomical single-bundle ACL reconstruction with patellar tendon autograft. The secondary purpose was to identify predictive factors for good outcome and occurrence of osteoarthritis.

METHODS

Sixty-three patients (m:f = 54:9; mean age at surgery, 27 ± 7 years) treated by ACL reconstruction were evaluated with a mean follow-up of 16 ± 1 years using IKDC2000, the SF36, Lysholm and Tegner score, Knee Society score, visual analogue scale for pain and satisfaction and KOOS. The femoral tunnel position was evaluated according to Sommer. It was also assessed in percentage of the Blumensaat line and the tibial tunnel position in percentage of the total anterior-posterior plateau length. The extent of osteoarthritis was graded according to the Kellgren-Lawrence score.

RESULTS

The total IKDC2000 was normal in 20 (32 %), nearly normal in 29 (46 %), abnormal in 12 (19 %) and severely abnormal in 3 (5 %) of patients. The mean total SF-36 was 89 ± 13, the Lysholm score 95 ± 12, the Knee Society score 191 ± 16 and the total KOOS 84 ± 19. The Tegner score decreased from pre-injury 7(4-10) to 6 (2-10) at follow-up. The Kellgren-Lawrence score was normal in 17 (27 %), suspected osteoarthritis in 25 (40 %), minimal osteoarthritis in 5 (8 %), moderate osteoarthritis in 9 (14 %) and severe osteoarthritis in 3 patients (5 %). The femoral tunnel was in zone A in 43 patients (68 %), in zone B in 16 (25 %) and in zone C in 4 patients (7 %). The femoral tunnel position in percentage of the Blumensaat line was 49 ± 3 (range, 44-57), and the tibial tunnel position in percentage of the total anterior-posterior plateau length was 32 ± 6 (range, 21-46). Patients with meniscal lesion at the time of ACL tear showed significantly less favourable outcomes than those without.

CONCLUSIONS

Patients treated by the proposed ACL reconstruction technique showed on average good to excellent long-term results. A meniscal lesion at the time of ACL tear was highly predictive for less favourable outcome.

Isolated anterior cruciate ligament reconstruction in patients aged fifty years: comparison of hamstring graft versus bone-patellar tendon-bone graft

PURPOSE

Anterior cruciate ligament (ACL) deficiency contributes to symptomatic functional instability of the knee, regardless of age. We evaluated patient-reported clinical outcome, instrumental stability and prevalence of radiological osteoarthritis based on two homogenous patient samples aged 50 years, an average of three years after isolated ACL reconstruction.

METHODS

ACL reconstruction using a bone-patellar tendon-bone (BPTB) autograft was done in 19 patients and a four-stranded semitendinosus tendon (ST) autograft in 22 patients. Clinical and functional follow-up assessment was performed an average of 32 months after surgical treatment. Clinical and functional follow-up assessment included the International Knee Documentation Committee (IKDC) score, Tegner score and Lysholm score. Instrumental stability testing was carried out using the KT-1000™ arthrometer. The degree of degenerative changes and prevalence of osteoarthritis was based on the Kellgren-Lawrence classification.

RESULTS

Mean follow-up was 32 months (range, 28-36). Mean age was 49.4 years in both groups. The median pre-injury Tegner score was 5.5 (range, 2-8) and the median preoperative Lysholm score was 35 (range, 15-69). At two years, all variables improved significantly for both groups compared to the preoperative values (P < 0.05), with no significant intergroup differences. Approximately 76 % of patients were graded A or B according to the IKDC score in both groups. Activity level according to the scores of Tegner and Lysholm was 4.9/5.3 and 83.4/82.5 on two-year-follow up in both groups. Radiological assessment reported degenerative changes of grade I Osteoarthritis (OA) in 36 % of patients. Grade-II OA was found in 31 % of patients. Grade-III OA and grade-IV OA were found in about 24 % and 7 % of all patients, respectively. Correlation analyses showed significant relationships between conservation of knee-joint stability and clinical outcome according to the IKDC score, and activity level according to the Lysholm score (p < 0.05).

CONCLUSION

Arthroscopic ACL reconstruction using either BPTB graft or hamstring graft in appropriately selected middle-aged patients results in patient satisfaction and good clinical results, with return to a reasonable level of activity regardless of surgical method and graft choice.

Osteoarthritis develops in the operated joint of an ovine model following ACL reconstruction with immediate anatomic reattachment of the native ACL

We tested the hypothesis that immediate reattachment of the native anterior cruciate ligament (ACL) can prevent kinematic changes and the development of osteoarthritis (OA). Five sheep underwent anatomic unilateral ACL reconstruction (ACL-R). Animals from a previous study served as sham (n = 7) or non-operated (n = 17) controls. At 4 points of walking gait, 6 degrees of freedom stifle joint kinematics of ACL-R animals were compared with sham controls at 4 and 20 weeks post-surgery. Gross cartilage, bone, and meniscal changes were graded at euthanasia; paired and differential scores were compared. Inter-animal differences were noted in all groups. Of 48 points of gait comparison between ACL-R and sham operated groups, 42 points showed no difference (p > 0.05). Of the six significant differences (p < 0.05), internal rotation in ACL-R animals accounted for three. At 20 weeks, differential scores showed that sham operated joints were morphologically indistinguishable from non-operated controls (p ≥ 0.129) while ACL-R joints had significantly higher combined cartilage and osteophyte scores than those controls (p ≤ 0.003). This method of ACL reconstruction in sheep did not restore normal walking gait kinematics completely and allowed some OA to develop in operated joints. OA may result from relatively subtle mechanical abnormalities, apparently more so in some individuals than others.

Acute single-stage reconstruction of multiligament knee injuries using the ligament advanced reinforcement system

OBJECTIVE

The purpose of the study was to report our early outcome in the management of multiligament knee injuries with the ligament advanced reinforcement system (LARS).

SUBJECTS AND METHODS

Between 2007 and 2010, 9 of 11 patients operated on for multiligament knee injuries were included in this study; 2 patients were excluded due to complicated neurovascular injuries, open knee dislocations and severe comorbidities. All patients were managed acutely (<3 weeks) by reconstructions of the cruciate and collateral ligaments with LARS ligament and were followed up for an average of 30 months (18-46 months).

RESULTS

The mean Lysholm score of the 9 patients at final follow-up was around 90 (range 88-94) with an average Tegner activity score of 5.5. The postoperative function of 1 case of KD-11 and 2 cases of KD-111 was rated as 'A,' while the remaining cases were rated 'B'. At final follow-up, minor osteoarthritic degeneration was detected in 1 case of KD-III and 2 cases of KD-IV. Superficial infection developed in 1 case, and no cases of knee synovitis and premature osteoarthritis were recorded.

CONCLUSION

A creditable outcome at mean of 30 months' follow-up was obtained in acute single-stage reconstruction of uncomplicated multiligament knee injuries with LARS ligament.

There is significant load sharing and physical interaction between the anteromedial and posterolateral bundles of the ovine ACL under anterior tibial loads

INTRODUCTION

The ovine stifle joint is an ideal preclinical model to test the ability of double-bundle reconstruction techniques in providing superior joint stability and less osteoarthritis (OA) compared with single-bundle techniques. However, knowledge of the normal ovine ACL and more specifically the load sharing and physical interaction between the two main bundles of the ovine ACL is currently limited.

METHODS

Six ovine stifle joints were tested using a robotic testing system. Each joint was cyclically loaded to 200N in the anterior tibial direction between 30° and 90° flexion and the force-displacement data were recorded for both the intact ACL, and when the anteromedial (AM, n=3) or the posterolateral bundle (PL, n=3) was transected.

RESULTS

The load shared by the AM bundle increased from 30° to 75° of flexion at all loading levels (25-200N); whereas, the load shared by the PL bundle decreased between full extension and mid flexion (60°) and then increased again. The load borne by the AM bundle did not change in response to increasing Anterior Tibial Loads (ATL) at each flexion angle, in contrast to the PL bundle (P=0.004). Physical interaction between bundles was greatest at 60° and under 50N ATL.

CONCLUSION

These data will help create double-bundle ACL reconstructions in sheep which are functionally similar to intact native ACL. In turn, this model can be used to examine the success of anatomically accurate double-bundle reconstructions to prevent the development of OA.

LEVEL OF EVIDENCE

III.

Urinary CTX-II concentrations are elevated and associated with knee pain and function in subjects with ACL reconstruction

OBJECTIVE

Post-traumatic knee osteoarthritis (OA) is prevalent after anterior cruciate ligament reconstruction (ACLR). Biomarkers that identify individuals likely to develop OA, especially symptomatic OA, can help target preventative and therapeutic strategies. This study examined the magnitude and change over time in urinary CTX-II (uCTX-II) concentrations shortly after ACL reconstruction, and, secondarily, the associations with knee pain and function.

DESIGN

Subjects were 28 patients with ACLR and 28 age- and sex-matched controls (CNTRL). Testing was conducted at four time points spaced 4 weeks apart (4, 8, 12 and 16 weeks post-operative in ACLR). Measures included demographics, urine samples, Numeric Pain Rating Scale (NPRS) and International Knee Documentation Committee Subjective Knee Form (IKDC-SKF). uCTX-II concentrations were determined with competitive enzyme-linked immunosorbent assay (ELISA). uCTX-II concentrations at each time point in ACLR were compared to the mean concentration over time in CNTRL, with and without adjustment for body mass index (BMI). Changes over time in each measure and correlations between the slopes of change were examined.

RESULTS

uCTX-II concentrations were significantly higher in ACLR than CNTRL through 16 weeks post-operative when adjusted for BMI. In ACLR, uCTX-II concentrations significantly decreased over time, and the slope was associated with NPRS (r = 0.406, P = 0.039) and IKDC-SKF (r = -0.402, P = 0.034) slopes.

CONCLUSION

uCTX-II concentrations shortly after ACLR were elevated compared to CNTRL and declined over time. Decreasing uCTX-II concentrations were associated with decreasing knee pain and improving function. uCTX-II may have a role as a prognostic marker following ACLR and warrants further investigation.

Second-look arthroscopic findings and clinical results after polyethylene terephthalate augmented anterior cruciate ligament reconstruction

PURPOSE

Based on the revival of artificial ligaments containing polyethylene terephthalate, this study aimed to evaluate objective intra-articular findings within scheduled second-look arthroscopy, patient-reported clinical outcome and stability after isolated augmented ACL reconstruction with polyethylene terephthalate (Trevira®) augmented patella-bone-tendon-bone graft.

METHODS

In a retrospective analysis of our institutional database, we found 126 patients with polyethylene terephthalate (Trevira®) augmented ACL reconstruction. All these patients underwent standardised second-look arthroscopic evaluation when removal of the augmentation became necessary. These second-look arthroscopic analyses focused on graft integration and remodelling in line with the polyethylene terephthalate augmentation. Arthroscopic re-examination comprised a graft evaluation including a structural and functional classification according to the Marburger Arthroscopy Score (MAS). Additional clinical evaluation was performed via the IKDC score and the scores of Tegner and Lysholm. Instrumental anterior laxity testing was carried out with a KT-1000™ arthrometer. Furthermore, a correlation analysis between the clinical parameters, the instrumental stability assessment and the corresponding arthroscopic graft condition was performed.

RESULTS

The arthroscopic evaluation showed rupture of 87 (69 %) of 126 augmentation devices. In 27 (31 %) of these 87 cases, synovial reactions were found particularly in the anterior compartment. An intact synthetic augmentation with signs of graft integration with intact synovial coating was only found in 30 %. Evaluation according to the MAS showed good to excellent structural and functional characteristics in 88 % of patients. Presence of a type III graft (MAS) was found in an additional 11 %. A rudimentary (type IV) graft was only detected once. Eighty-five percent of patients were graded A or B according to IKDC score. The Lysholm score was 92.4 ± 4.8. Correlation analysis demonstrated a significant relationship between clinical outcome according to the IKDC score (p<0.05), instrumental stability performance according to the KT-1000™ assessment (p<0.05) and the corresponding arthroscopic graft evaluation according to the MAS.

CONCLUSION

Graft integration and remodelling has complex and multi-factorial origins, particularly with artificial augmentation. Correlation analysis showed a significant relation between clinical condition, instrumental stability performance and arthroscopic graft constitution. The release of polyethylene terephthalate fibres caused inflammation of synovial tissue of the knee. Characteristic sub-clinical graft changes of structural, morphological and functional qualities of the inserted graft appear on second-look arthroscopy despite good clinical results.

Clinical outcome and prevalence of osteoarthritis after isolated anterior cruciate ligament reconstruction using hamstring graft: follow-up after two and ten years

PURPOSE

The aim of this study was to evaluate patient-reported clinical outcome, instrumental stability and prevalence of radiological osteoarthritis (OA) based on a homogeneous patient sample after two years and on average ten years after isolated anterior cruciate ligament (ACL) reconstruction.

METHODS

Primarily we performed ACL reconstruction using a four-strand semitendinosus tendon (ST) autograft in 112 patients. Two years after reconstruction 98 patients could be re-evaluated. Long-term clinical and functional follow-up assessment was then performed on 52 patients on average 10.2 years after operative treatment. Inclusion criteria consisted of an isolated ACL rupture, reconstruction with ST graft and no associated cartilage alterations and meniscal lesions. Clinical and functional follow-up assessment included the International Knee Documentation Committee (IKDC) score and the scores of Tegner and Lysholm. Instrumental stability testing was carried out with the KT1000™ arthrometer. The degree of degenerative changes and prevalence of OA was based on the Jäger-Wirth score.

RESULTS

The mean long-term follow-up was 10.2 years (eight-13 years), and the mean age was 40.4 years (24-62 years). About 72 % of patients were graded A or B according to the IKDC score. Activity levels according to the scores of Tegner and Lysholm were 4.8 and 88.2 on long-term follow-up. Radiological assessment revealed degenerative changes in the sense of a grade I OA in 21.2 % of patients. Prevalence of a grade II OA was found in 53.8 % of patients. A grade III OA and a grade IV OA were found in 19.2 and 5.7 %. Correlation analysis showed significant relationships between the long-term stability and prevalence of OA (p<0.05).

CONCLUSIONS

Arthroscopic ACL reconstruction using four-strand ST autograft resulted in high patient satisfaction and good clinical results at two years and long-term follow-up. The prevalence of higher degree OA that developed in about 25 % of patients is significantly correlated with long-term knee joint stability.

Guideline on anterior cruciate ligament injury

The Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulated by a steering group of the Dutch Orthopaedic Association. What is the role of physical examination and additional diagnostic tools? Which patient-related outcome measures should be used? What are the relevant parameters that influence the indication for an ACL reconstruction? Which findings or complaints are predictive of a bad result of an ACL injury treatment? What is the optimal timing for surgery for an ACL injury? What is the outcome of different conservative treatment modalities? Which kind of graft gives the best result in an ACL reconstruction? What is the optimal postoperative treatment concerning rehabilitation, resumption of sports, and physiotherapy? These 8 questions were answered and recommendations were made, using the "Appraisal of Guidelines for Research and Evaluation" instrument. This instrument seeks to improve the quality and effectiveness of clinical practical guidelines by establishing a shared framework to develop, report, and assess. The steering group has also developed 7 internal indicators to aid in measuring and enhancing the quality of the treatment of patients with an ACL injury, for use in a hospital or practice.

Health-related quality of life and direct costs in patients with anterior cruciate ligament injury: single-bundle versus double-bundle reconstruction in a low-demand cohort--a randomized trial with 2 years of follow-up

PURPOSE

To evaluate health-related quality of life (HRQL) in patients undergoing anterior cruciate ligament (ACL) reconstructive surgery by use of 2 procedures and to estimate the direct costs of surgery.

METHODS

We performed a 2-year randomized, prospective intervention study of 2 surgical ACL reconstruction techniques (anatomic single bundle [SB] v double bundle [DB]). Fifty-five consecutive outpatients, with a mean age of 30.88 years, were randomized to SB or DB ACL reconstruction. The Medical Outcomes Study 36-item Short Form Health Survey (SF-36) was used to measure HRQL (primary outcome). ACL injuries were assessed by the International Knee Documentation Committee (IKDC) score (secondary outcome). The use of medical resources and their costs were evaluated.

RESULTS

We included 52 patients in the final analyses (23 in the SB group and 29 in the DB group). At baseline, there were no significant differences in study variables. At 2 years of follow-up, there were no significant differences in SF-36 and IKDC scores between groups. However, compared with baseline, the SF-36 physical function, physical role, bodily pain, social function, and emotional role scores were significantly better in the SB group (P < .05), whereas only the physical function dimension score was better in the DB group (P = .047). IKDC scores at 2 years improved significantly in the SB group (P < .001) and DB group (P = .004) compared with baseline. There was a significant correlation between the SF-36 physical function, physical role, and bodily pain dimensions and the IKDC score at 2 years (P < .05). The costs were € 3,251 for the SB group and € 4,172 for the DB group.

CONCLUSIONS

HRQL and medical outcomes were similar between SB and DB ACL reconstruction techniques, 2 years after surgery. However, the SB technique was more cost-effective.

Extensive heterotopic ossification after suspensory cortical fixation of acute distal biceps tendon ruptures

Suspensory cortical fixation is commonly used for distal biceps tendon repair and reconstruction with one of several commercially available devices. The single-incision approach typically used with these devices is believed to have a lower incidence of heterotopic ossification than the dual-incision technique, but the true incidence of heterotopic ossification is unknown. The role of chemotherapeutic or radiation prophylaxis is undefined. We have identified 4 cases of extensive heterotopic ossification after biceps fixation with a suspensory button and single-incision approach. Surgeons should be aware of this potential complication when using suspensory cortical buttons for distal biceps fixation.

A review of systematic reviews on anterior cruciate ligament reconstruction rehabilitation

The aim of this systematic review of systematic reviews was to critically appraise systematic reviews on Anterior Cruciate Ligament (ACL) reconstruction rehabilitation to determine which interventions are supported by the highest quality evidence. Electronic searches were undertaken, of MEDLINE, AMED, EMBASE, EBM reviews, PEDro, Scopus, and Web of Science to identify systematic reviews of ACL rehabilitation. Two reviewers independently selected the studies, extracted data, and applied quality criteria. Study quality was assessed using PRISMA and a best evidence synthesis was performed. Five systematic reviews were included assessing eight rehabilitation components. There was strong evidence (consistent evidence from multiple high quality randomised controlled trials (RCTs)) of no added benefit of bracing (0-6 weeks post-surgery) compared to standard treatment in the short term. Moderate evidence (consistent evidence from multiple low quality RCTs and/or one high quality RCT) supported no added benefit of continuous passive motion to standard treatment for increasing range of motion. There was moderate evidence of equal effectiveness of closed versus open kinetic chain exercise and home versus clinic based rehabilitation, on a range of short term outcomes. There was inconsistent or limited evidence for some interventions. Recommendations for clinical practice are made at specific time points for specific outcomes.

A between sex comparison of anterior-posterior knee laxity after anterior cruciate ligament reconstruction with patellar tendon or hamstrings autograft: a systematic review

Anterior-posterior (AP) knee laxity after anterior cruciate ligament (ACL) reconstruction may differ between sexes for different graft types. Females may experience an increase in AP knee laxity following an ACL reconstruction with a hamstrings graft, which is not seen in males with a hamstrings graft or in males or females with a bone-patellar tendon-bone (BTB) graft. The hypothesis of this review is sex differences in AP knee laxity and this will be identified in patients who undergo an ACL reconstruction with a hamstrings graft, while no sex differences will be observed in patients who have an ACL reconstruction with a BTB graft. A systematic search was performed in PubMed, CINAHL and SPORTDiscus. Inclusion criteria were articles published in the English language that studied human subjects who underwent an ACL reconstruction with a BTB or hamstrings autograft, and the presence of a sex comparison on outcome measures including side-to-side difference in AP knee laxity. Methodological quality was assessed using a Modified Coleman Methodology Score. Eleven cohort studies met the inclusion criteria. Six investigated sex differences in both hamstrings and BTB grafts. Three only investigated BTB grafts and two only investigated hamstrings grafts. These studies consistently reported increases in AP knee laxity in females after an ACL reconstruction with a hamstrings graft that was not observed in the other cohorts. This systematic review indicates that female patients have greater AP knee laxity following an ACL reconstruction with a hamstrings autograft compared with males with a similar procedure, and both females and males following an ACL reconstruction with a BTB autograft. These results are derived from lower level evidence, as no randomized control trials have attempted to answer this question. Future studies need to rigorously address this clinical question to confirm the results currently in the literature.

Graft-dependent differences in the ligamentization process of anterior cruciate ligament grafts in a sheep trial

PURPOSE

The structural properties of the healing ligament are the determining factor for the stability of the reconstruction before, during, and after osseous integration of anterior cruciate ligament grafts. Over the course of ligamentization, the stability of synovialized grafts seems lower than that of non-synovialized patellar tendon grafts.

METHODS

In an animal study on 42 sheep, 21 non-synovialized grafts (patellar tendon) and 21 synovialized grafts (flexor digitorum superficialis tendon) were performed to replace the anterior cruciate ligament. After 6, 12, and 24 weeks, 7 animals from each group were euthanized and investigated. Anteroposterior stability of the knee was assessed. After removal of all other soft tissues, the ACL was loaded to failure. Histology and histological analysis of the intra-articular graft region was then performed.

RESULTS

There were no significant differences in the translation test comparing synovialized and non-synovialized grafts. After 6, 12, and 24 weeks, all transplants failed in the tensile test due to interligamentous rupture or avulsion. After 6 weeks, transplants did not show significant biomechanical differences. Load to failure and stiffness of the patellar tendon was more than twice those of synovialized tendon (P = 0.002) after 12 weeks. Histology revealed necrosis in patellar tendon specimens after 12 weeks. A significant increase in load to failure was determined in synovialized ligament grafts between 12 and 24 weeks (P = 0.005). Its load capacity then tended to be higher than that of patellar tendon grafts.

CONCLUSION

The stability of synovialized ligament grafts is significantly lower than that of non-synovialized patellar tendon grafts after 12 weeks. This difference is compensated after 24 weeks. The significantly lower load to failure of synovialized compared with non-synovialized grafts after 12 weeks may be clinically relevant for the rehabilitation process of anterior cruciate ligament grafts in humans.

Does computer navigation system really improve early clinical outcomes after anterior cruciate ligament reconstruction? A meta-analysis and systematic review of randomized controlled trials

Inaccurate tunnel placement is an important cause of failure in conventional anterior cruciate ligament (ACL) reconstruction. Controversy currently exists over the usefulness of computer-assisted navigation systems in addressing this problem. Five randomized or quasi-randomized, controlled trials comparing computer-navigated versus conventional technique in ACL reconstructions until December 1, 2009 were identified through a systematical database search. The clinical outcomes of the trials were analyzed by Lachman test, pivot-shift test, International Knee Documentation Committee knee score, Lysholm score, and Tegner score. Mean difference or risk ratio with 95% confidence interval was calculated using a fixed-effects or random-effects model. Heterogeneity across the studies was also assessed. We found that the use of computer-assisted navigation systems led to additional operative time (8-17min). No significant differences between computer-navigated and conventional groups were found in terms of knee stability and functional assessment during short-term follow-up. The role of computer-assisted navigation systems on clinical performance and longevity needs further investigation in large sample, long-term randomized trials.

Why perform an ACL augmentation?

PURPOSE

The objective of this article is to determine the importance of an intact anterior cruciate ligament (ACL) stump and its role in the clinical outcome of an ACL reconstruction.

METHOD

A PubMed database search was conducted using the key words "anterior cruciate ligament healing" and "double-bundle structure". Articles concerning ACL healing, reconstruction, and rehabilitation were obtained. A total of 35 studies were incorporated in this article, and factors preset in the intact ACL stump were taken into consideration.

RESULTS

Four factors were noted to be important in preserving the stump: protection in early rehabilitation, maintenance of vascular supply, preservation of proprioceptive receptors and may serve as reference for accurate tunnel placement. Also noted was the significance of the intact stump in the natural history, examination, and imaging of such injuries.

CONCLUSION

This study provides a detailed justification in preserving ACL remnants and their vital role in surgical reconstruction of partial anterior cruciate ligament tears.

Does anterior cruciate ligament reconstruction lead to degenerative disease?: Thirteen-year results after bone-patellar tendon-bone autograft

BACKGROUND

Reporting of long-term outcome of anterior cruciate ligament (ACL) reconstruction with the patellar tendon (bone-patellar tendon-bone [BTB]) autograft is limited. There are concerns that degenerative joint disease is common in the long term, which may be associated with the procedure itself.

HYPOTHESES

(1) ACL reconstruction with BTB provides good long-term outcome. (2) There are additional factors to surgical reconstruction that can be associated with the development of degenerative disease.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Of 161 patients, 114 were eligible. Patient-centered outcome was by Lysholm and subjective International Knee Documentation Committee (IKDC) score; objective outcome measures were clinical examination and IKDC radiological grade.

RESULTS

Mean average follow-up was 13 years. The IKDC radiological grades in the worst compartment were A = 15%, B = 51%, C = 19%, and D = 14% (n = 83). There was a significant difference between the injured versus contralateral uninjured knee (n = 42, P = .003). In a subgroup with no meniscal or chondral injury the IKDC grades were A = 38%, B = 55%, C = 7%, and D = 0% (n = 29). The mean subjective scores were 89 ± 11 (Lysholm) and 83 ± 15 (IKDC) (n = 114). Poor IKDC subjective outcome was associated with chondral injury (P = .001), previous surgery (P = .022), return to sport (P = .013), and poor radiological grade in the ipsilateral medial compartment (P = .004). A poor IKDC radiological grade was associated with chondral injury (P = .002), meniscal injury (P = .010) and meniscectomy (P = .012), an IKDC subjective score of <85 (P = .01), and poor radiological grade in the contralateral medial compartment (P = .041).

CONCLUSION

At 13 years, BTB ACL reconstruction provides a good outcome. Chondral and meniscal damage at surgery were associated with a poor radiological outcome, indicating that injuries sustained during ACL rupture may be the main predictors of degenerative bone disease.

Isokinetic muscle strength and knee function associated with double femoral pin fixation and fixation with interference screw in anterior cruciate ligament reconstruction

PURPOSE

Intensive scheduling in sports requires athletes to resume physical activity shortly after injury. The purpose of this study was to investigate early isokinetic muscle strength and knee function on bone-patellar tendon-bone (BPTB) ACL reconstruction with double femoral pin fixation or interference screw technique.

METHODS

A prospective study was conducted from 2008 to 2009, with 48 athletes who received femoral BPTB fixation with interference screw (n = 26) or double pin (n = 22). Clinical (IKDC objective score and hop test) and isokinetic muscle strength (peak torque (PT), PT/body weight and flexion/extension rate (F/E) in 60 and 240°/s) were analyzed at 6 months of follow-up.

RESULTS

Analysis at baseline showed no differences between groups before surgery related to age, gender, associated injury, Tegner or Lysholm score; thus showing that groups were similar. During follow-up, however, there were significant differences between the two groups in some of the isokinetic muscle strength: PT/BW 60°/s (Double Pin = 200% ± 13% vs. Interference Screw = 253% ± 16%*, *P = 0.01); F/E 60°/s (Double Pin = 89% ± 29%* vs. Interference Screw = 74% ± 12%, *P = 0.04). No statistical differences between groups were observed on IKDC objective score, hop test and complications.

CONCLUSION

The significant muscle strength outcome of the interference screw group found in this study gives initial evidence that this fixation technique is useful for athletes that may need accelerated rehabilitation. Early return to sports ability signaled by isokinetic muscle strength is of clinical relevance as it is one of the main goals for athletes' rehabilitation.

Kinetic chains: a review of the concept and its clinical applications

During the past decade, our understanding of biomechanics and its importance in rehabilitation has advanced significantly. The kinetic chain, a concept borrowed from engineering, has helped us better understand the underlying physiology of human movement. This understanding, in turn, has facilitated the development of new and more rational rehabilitation strategies. The kinetic chain concept has application in a wide spectrum of clinical conditions, including musculoskeletal medicine, sports medicine, and neurorehabilitation, as well as prosthetics and orthotics. The purpose of this review is to provide insights into the biomechanics related to the concept of kinetic chains, with a specific focus on closed kinetic chains and its clinical applications in rehabilitation.

Anterior cruciate ligament tears: conservative or surgical treatment? A critical review of the literature

PURPOSE

Is it rational to recommend surgical reconstruction of the torn anterior cruciate ligament to every patient? Is conservative management still a valid option?

METHOD

Through a literature review, we looked for the arguments from each side and checked their validity.

RESULTS

Unfortunately results of most studies cannot be compared because of the following reasons not exhaustively cited: studied populations differed with respect to age, sex, professional and sports activity level, lesions associated with ACL rupture, patient recruitment methods, time from injury to treatment and different therapeutic modalities. Furthermore, various methods were used to evaluate the clinical and radiological results and there was no consensus of their interpretation. Some authors assumed that the incidence of further meniscus lesions could probably be reduced if the torn ACL was surgically reconstructed. But, we have no evidence to believe that this would be due to the surgical repair rather than to a decrease of involvement in strenuous activities. At present it is not demonstrated that ACL-plasty can prevent osteoarthritis. Numerous factors could explain evolution to arthrosis whatever the treatment for the ACL-ruptured knee. Studies comparing surgical and conservative treatments confirm that ACL reconstruction is not the pre-requisite for returning to sporting activities. More recent and scientifically well-designed studies demonstrate that conservative treatment could give satisfactory results for many patients. They suggest some methods to help them choose the best treatment.

CONCLUSION

At present there are no evidence-based arguments to recommend a systematic surgical reconstruction to any patient who tore his ACL. Knee stability can be improved not only by surgery but also by neuromuscular rehabilitation. Whatever the treatment, fully normal knee kinematics are not restored. While the patients wish to go back to their sport and want everything possible done to prolong their ability to perform these activities, they should be informed that the risk of further knee lesions and osteoarthritis remains high, whatever the treatment, surgical or conservative.

LEVEL OF EVIDENCE

Systematic review of Level I, II, III and IV studies, Level IV.

Bioabsorbable interference screw versus bioabsorbable cross pins: influence of femoral graft fixation on the clinical outcome after ACL reconstruction

PURPOSE

The aim of this study was to evaluate the clinical outcome and differences in anterior–posterior laxity of ACL reconstruction using a bioabsorbable interference screw for femoral graft fixation when compared to femoral bioabsorbable cross pin fixation.

METHODS

Clinical outcome was evaluated among 59 patients 1 year after arthroscopic ACL reconstruction with hamstrings graft in a prospective, non-randomised study. In 31 cases, femoral fixation of the graft was performed using a bioabsorbable interference screw. In 28 cases, two bioabsorbable cross pins were used for femoral fixation. Patients were evaluated using Tegner, Lysholm and Marshall scores, the visual analogue scale for pain and KT-1000 arthrometer measurement.

RESULTS

No significant difference (P ≥ 0.05) was observed at follow-up for the knee scores. The average Tegner score was 5.83 points (±2.00) for the interference screw fixation and 5.83 points (±1.24) for the cross pin fixation; the average Lysholm score was 93.58 (±5.79) to 92.72 (±6.34) points; and the average Marshall score 46.72 (±2.4) to 47.30 (±2.35) points. No significant difference was found for the visual analogue scale for pain. KT-1000 arthrometer measurement revealed a significant (P < 0.05) difference in the mean side-to-side anterior translation at all applied forces. At 67 N, the mean difference was 1.53 mm (±1.24) in the interference screw group and 0.47 mm (±1.18) in the cross pin group (P < 0.05). At 89 N, the mean differences were 1.85 mm (±1.29) versus 0.59 mm (±1.59), respectively, (P < 0.05), and maximum manual displacements were 2.02 mm (±1.26) versus 1.22 mm (1.18; P < 0.05).

CONCLUSIONS

In ACL reconstruction with hamstrings graft, similar clinical results are obtained for the use of bioabsorbable cross pins when compared to bioabsorbable interference screws for femoral fixation. Cross pin fixation was superior with regard to the anteroposterior laxity as measured with KT-1000.

Accelerated versus nonaccelerated rehabilitation after anterior cruciate ligament reconstruction: a prospective, randomized, double-blind investigation evaluating knee joint laxity using roentgen stereophotogrammetric analysis

BACKGROUND

The relationship between the biomechanical dose of rehabilitation exercises administered after anterior cruciate ligament (ACL) reconstruction and the healing response of the graft and knee is not well understood.

HYPOTHESIS

After ACL reconstruction, rehabilitation administered with either accelerated or nonaccelerated programs produces the same change in the knees' 6 degrees of freedom, or envelope, laxity values.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients who underwent ACL reconstruction with a bone-patellar tendon-bone autograft were randomized to rehabilitation with either accelerated (19 week) or nonaccelerated (32 week) programs. At the time of surgery, and then 3, 6, 12, and 24 months later, the 6 degrees of freedom knee laxity values were measured using roentgen stereophotogrammetric analysis and clinical, functional, and patient-oriented outcome measures.

RESULTS

Eighty-five percent of those enrolled were followed through 2 years. Laxity of the reconstructed knee was restored to within the limits of the contralateral, normal side at the time of surgery (baseline) in all participants. Patients in both programs underwent a similar increase in the envelope of knee laxity over the 2-year follow-up interval (anterior-posterior translation 3.2 vs 4.5 mm, and coupled internal-external rotations 2.6° vs 1.9° for participants in the accelerated and nonaccelerated programs, respectively). Those who underwent accelerated rehabilitation experienced a significant improvement in thigh muscle strength at the 3-month follow-up (P < .05) compared with those who participated in nonaccelerated rehabilitation, but no differences between the programs were seen after this time interval. At the 2-year follow-up, the groups were similar in terms of clinical assessment, patient satisfaction, function, proprioception, and isokinetic thigh muscle strength.

CONCLUSION

Rehabilitation with the accelerated and nonaccelerated programs administered in this study produced the same increase in the envelope of knee laxity. A majority of the increase in the envelope of knee laxity occurred during healing when exercises were advanced and activity level increased. Patients in both programs had the same clinical assessment, functional performance, proprioception, and thigh muscle strength, which returned to normal levels after healing was complete. For participants in both treatment programs, the Knee Injury and Osteoarthritis Outcome Score (KOOS) assessment of quality of life did not return to preinjury levels.

Intraarticular application of autologous conditioned serum (ACS) reduces bone tunnel widening after ACL reconstructive surgery in a randomized controlled trial

PURPOSE

Pro-inflammatory cytokines play a pivotal role in osteoarthritis, as well as in bone tunnel widening after ACL reconstructive surgery. A new treatment option is to administer autologous conditioned serum (ACS) containing endogenous anti-inflammatory cytokines including IL-1Ra and growth factors (IGF-1, PDGF, and TGF-β1, among others) in the liquid blood phase. The purpose of this trial was to establish whether the postoperative outcome could be affected by intraarticular application of ACS.

METHODS

In a prospective, randomized, double-blinded, placebo-controlled trial with two parallel groups, 62 patients were treated. Bone tunnel width was measured by CT scans, while clinical efficacy was assessed by patient-administered outcome instruments (WOMAC, IKDC 2000) up to 1 year following the ACL reconstruction in patients receiving either ACS (Group A) or placebo (Group B). We compared the levels and dynamics of IL-1β concentrations in the synovial liquid and examined the correlation between the levels of IL-1β at three different postoperative points.

RESULTS

Bone tunnel enlargement was significantly less (6 months: 8%, 12 months: 13%) in Group A than in Group B (6 months: 31%, 12 months: 38%). Clinical outcomes (WOMAC, IKDC 2000) were consistently better in patients treated with ACS at all data points and for all outcome parameters, and there were statistically significant differences in the WOMAC stiffness subscale after 1 year. The decrease in IL-1β synovial fluid concentration was more pronounced in the ACS group, and values were lower, to a statistically significant degree, in the ACS group at day 10.

CONCLUSION

The intraarticular administration/injection of ACS results in decreased bone tunnel widening after ACL reconstructive surgery.

Functional and muscle morphometric effects of ACL reconstruction. A prospective CT study with 1 year follow-up

Computed tomography (CT) was used to explore if changes in muscle cross-sectional area and quality after anterior cruciate ligament (ACL) injury and reconstruction would be related to knee function. Fourteen females and 23 males (16-54 years) underwent clinical tests, subjective questionnaires, and CT 1 week before and 1 year after ACL surgery with semitendinosus-gracilis (STG) graft and rehabilitation. Postoperatively, knee laxity was decreased and functional knee measures and subjective patient scores improved. The most obvious remaining deficit was the quadriceps atrophy, which was significantly larger if the right leg was injured. Right-leg injury also tended to cause larger compensatory hypertrophy of the combined knee flexor and tibial internal rotator muscles (preoperatively). The quadriceps atrophy was significantly correlated with the scores and functional tests, the latter also being related to the remaining size of the gracilis muscle. Biceps femoris hypertrophy and, in males only, semimembranosus hypertrophy was observed following the ACL reconstruction. The lack of semimembranosus hypertrophy in the women could, via tibial internal rotation torque deficit, contribute to the less favorable functional and subjective outcome recorded for the women. The results indicate that the quadriceps, the combined knee flexor/tibial internal rotator muscles, side of ACL injury, and sex are important to consider in rehabilitation after STG graft.

Muscle strength and hop performance criteria prior to return to sports after ACL reconstruction

PURPOSE

The purpose of this article is to present recommendations for new muscle strength and hop performance criteria prior to a return to sports after anterior cruciate ligament (ACL) reconstruction.

METHODS

A search was made of relevant literature relating to muscle function, self-reported questionnaires on symptoms, function and knee-related quality of life, as well as the rate of re-injury, the rate of return to sports and the development of osteoarthritis after ACL reconstruction. The literature was reviewed and discussed by the European Board of Sports Rehabilitation in order to reach consensus on criteria for muscle strength and hop performance prior to a return to sports.

RESULTS

The majority of athletes that sustain an (ACL) injury do not successfully return to their pre-injury sport, even though most athletes achieve what is considered to be acceptable muscle function. On self-reported questionnaires, the athletes report high ratings for fear of re-injury, low ratings for their knee function during sports and low ratings for their knee-related quality of life.

CONCLUSION

The conclusion is that the muscle function tests that are commonly used are not demanding enough or not sensitive enough to identify differences between injured and non-injured sides. Recommendations for new criteria are given for the sports medicine community to consider, before allowing an athlete to return to sports after an ACL reconstruction.

Outcome of surgical treatment of arthrofibrosis following ligament reconstruction

PURPOSE

Clinical outcome following surgical treatment and intensive physiotherapy was evaluated in patients with arthrofibrosis as a complication to varying knee-ligament reconstructions.

METHODS

From 2003 to 2007, 31 patients underwent surgery for arthrofibrosis as a postoperative complication following knee-ligament reconstruction. Treatment for reduced range of motion consisted of forced manipulation or arthroscopic arthrolysis followed by intensive physiotherapy. Twenty-seven patients (12 men and 15 women; median age 35(12-70) years) were followed up. Objective examination, Pain, KOOS and Tegner scores were used to evaluate the clinical outcome at follow-up.

RESULTS

Fourteen patients were treated with forced manipulation alone, and the remaining thirteen were treated with forced manipulation and arthroscopic arthrolysis. The patients' median follow-up was 51 months (19-73 months). Median interval between primary surgery and surgical release was 4 (1-32) months. Median range of motion (ROM) improved from -0°(0 to 20) to 0°(+2-9) in extension deficit and from 90°(40-145) to 130°(90-155) in flexion. Mean KOOS score were symptoms 63, pain 72, ADL 77, sport 42, QOL 45. Median Tegner score was 4 (2-9).

CONCLUSION

Surgical arthrolysis combined with intensive physiotherapy improved range of motion to nearly normal values. Subjective outcome scores revealed relatively poor outcome levels compared to uncomplicated knee-ligament reconstruction. Predictors of poor outcome were global arthrofibrosis and greater than 6-month time interval from primary reconstruction and surgical release.

LEVEL OF EVIDENCE

Retrospective clinical case series, Level IV.