Arthroscopically assisted reconstruction of the anterior cruciate ligament with use of autogenous patellar-ligament grafts. Results after twenty-four to forty-two months

A Comparison of Results in Older, Middle-aged, and Younger Patients after Primary Anterior Cruciate Ligament Reconstruction: Minimum 10-Year Follow-up

Background

Anterior cruciate ligament (ACL) reconstruction is commonly performed to prevent decreased knee function and restore stability in middle-aged and even older patients. However, few studies have compared the long-term clinical outcomes of ACL reconstruction between older, younger, and middle-aged patients. The purpose of this study was to compare the long-term clinical outcomes of ACL reconstruction in older patients with those in younger and middle-aged patients.

Methods

A total of 352 patients who underwent primary ACL reconstruction between January 2003 and March 2008 were retrospectively reviewed and classified into three groups (group A: 246 [age, 20-29 years], group B: 72 [age, 40-49 years], group C: 34 [age, 50-65 years]). The mean follow-up period was 14.2 ± 1.6 years. Clinical outcomes were evaluated and compared between groups.

Results

The differences in the range of motion, clinical scores, and stability tests were not statistically significant among the three groups. The difference in the graft failure rate among the three groups was significant (group A: 16 [6.5%], group B: 7 [9.7%], group C: 6 [17.6%]; p = 0.040). In particular, when compared between the two groups, there was a significant difference between group A and group C (p = 0.036). The 10-year survival rates were 93.5%, 90.3%, and 82.4% for groups A, B, and C, respectively (p = 0.048).

Conclusions

Although graft failure rates were higher in older patients than younger and middle-aged patients, clinical outcomes of ACL reconstruction in older patients were comparable to those of younger and middle-aged patients in terms of the range of motion, clinical scores, and stability tests at a minimum follow-up of 10 years.

ACL Reconstruction Combined With the Arnold-Coker Modification of the MacIntosh Lateral Extra-articular Tenodesis: Long-term Clinical and Radiological Outcomes

BACKGROUND

Interest in the role of lateral extra-articular tenodesis (LET) in preventing rotatory instability and the pivot-shift phenomenon after anterior cruciate ligament reconstruction (ACLR) has been recently renewed. Nevertheless, there is still concern about overconstraint of the lateral compartment of the knee and the risk of subsequent osteoarthritis (OA).

PURPOSE

The purpose of this retrospective study was to compare long-term subjective and objective outcomes and the rate of OA development between patients undergoing isolated ACLR (iACLR) with a hamstring tendon autograft and those with a combined Arnold-Coker modification of the McIntosh extra-articular procedure. Risk factors for long-term OA were evaluated.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The study included 165 consecutive patients treated at a single center by ACLR. A total of 86 patients underwent iACLR (iACLR group) and 79 received combined intra- and extra-articular reconstruction (ACLR+LET). The International Knee Documentation Committee (IKDC), Lysholm, and Tegner activity scores were administered. Knee stability was tested through the Lachman test, the pivot-shift test, and the KT-1000 knee arthrometer test. A positive pivot-shift test (++/+++), laxity on the KT-1000, and referred giving-way episodes or revision ACLR were considered failures. Radiographic results were assessed according to the Fairbank, IKDC, and Kellgren-Lawrence scales. Radiographic evaluation included both the overall tibiofemoral joint and the medial and lateral compartment separately. A univariate and a multivariate logistic regression with penalized maximum likelihood was used to identify risks factors associated with long-term OA.

RESULTS

The mean follow-up was 15.7 years. There were no statistically significant differences in subjective scores between the 2 groups. A side-to-side difference >5 mm on the KT-1000 arthrometer evaluation was found in 8 patients in the iACLR group and in 1 patient in the ACLR+LET group (P = .01). Nine cases of failure were found in the iACLR group and only 1 case was found in the ACLR+LET group (P = .0093). Patients in the iACLR group had a significantly higher OA grades than those in the ACLR+LET group for the overall tibiofemoral joint and the lateral compartment of the knee. No differences were found in the medial compartment. A higher level of lateral compartment OA was found in patients who received partial lateral meniscectomy in the iACLR group compared with those in the ACLR+LET group. Univariate and multivariate analysis results demonstrated that meniscectomy was the most significant factor for long-term OA development.

CONCLUSION

A significantly higher risk of long-term OA was found with iACLR than with ACLR combined with the Arnold-Coker modification of the McIntosh extra-articular procedure. Knees with combined ACLR also had a significantly lower OA grade after partial lateral meniscectomy. Additionally, those undergoing combined ACLR had better knee stability and lower graft rupture rates at the long-term follow-up. Partial meniscectomy was the main risk factor negatively associated with OA changes.

Mechanical and fatigue behaviour of artificial ligaments (ALs)

A flexible biologic band, ACL is the most injured and ruptured ligament in the knees of humans and animals. This research aims to produce synthetic anterior cruciate ligaments (ACLs) and compare these ligaments' mechanical and fatigue life properties with the natural ACL and commercial synthetic grafts. Artificial ligaments were designed as a core-sheath type structure. The core consisted of straight, parallel yarns and the sheath was a tubular fabric produced by weaving or braiding techniques from polyester or Vectran® yarns. The mechanical properties of the resulting artificial ligaments (AL) were tested before and after the fatigue test and compared to those of the natural ACL and commercial artificial ACLs in the market. Results showed that all ligaments had sufficient tensile strength, and they retained it after the fatigue test. If constructed sheath and core parts were from the same type of yarns, the breaking load of ligaments was higher. The breaking strain and stiffness of woven structures, particularly with Vectran cores, were better than braided ones. After the fatigue test, the breaking strain and stiffness of AL structures with a braided sheath or polyester core were improved. This finding suggests that to prevent the laxity of knee preconditioning of the ligament is necessary if the fabric structure or yarn inherently has high breaking strain and low stiffness. Overall, this study shows that a variety of suitable candidates for replacing ruptured anterior cruciate ligaments could be developed by carefully combining the fatigue-resistant yarns with leno, narrow, and braided structures.

The Top 50 Most-Cited Knee Arthroscopy Studies

Purpose

To objectively identify the 50 most influential studies in knee arthroscopy and provide an analysis of their key characteristics.

Methods

The Clarivate Analytics Web of Knowledge database was used to gather data and metrics of knee arthroscopy research. The search list was sorted by the number of citations, and articles were included or excluded based on relevance to knee arthroscopy. The information extracted for each article included author name, publication year, country of origin, journal name, article type, and the level of evidence.

Results

For these 50 studies, the total number of citations was calculated to be 12,168, with an average of 243.4 citations per paper. The most-cited article was cited 1,220 times. The 50 studies included in this analysis were published between 1972 and 2013. All 50 articles were published in English and came from 10 different orthopaedic journals. The United States was responsible for the majority of articles (n = 26); however, many other countries were represented. The most prevalent study designs were case series (n = 20).

Conclusions

The 50 most influential articles in knee arthroscopy were cited a total of 12,168 times. The study designs most commonly used were case series and cohort studies. This article serves as a reference to direct orthopaedic practitioners to the 50 most influential studies in knee arthroscopy. We hope that these 50 studies and the analysis we provide help health care professionals efficiently assess consensus, trends, and needs within the field.

Clinical Relevance

This analysis of the 50 most influential studies in knee arthroscopy will provide medical students, residents, fellows, and attending physicians with a comprehensive inventory and citation analysis of the most impactful academic contributions to one of the most important fields within orthopaedic surgery.

ACL reconstruction with lateral extra-articular tenodesis using a continuous graft: 10-year outcomes of 50 cases

BACKGROUND

Persistence of pivot shift is the main problem after isolated intra-articular anterior cruciate ligament (ACL) reconstruction. Adding lateral extra-articular tenodesis (LET) to the ACL procedure increases the knee's stability by controlling rotational laxity. The aim of this study was to evaluate the long-term clinical and radiological outcomes of combined ACL reconstruction with LET using a continuous hamstring graft as a first-line procedure.

MATERIAL AND METHODS

Fifty patients were reviewed at 10 years postoperative. Subjective outcome scores -IKDC, Lysholm, KOOS and Tegner- were collected. A clinical and radiological assessment was done. The knees' anteroposterior laxity was measured with a rollimeter.

RESULTS

The mean IKDC subjective score was 85.5, the mean Lysholm score was 90.2 and 80% of patients had a score graded as good or very good. No pivot shift was present in 94% of patients and there was a firm endpoint in the Lachman test in 86% of patients. There was a flexion deficit>5° in 5 patients and an extension deficit of 10° in one patient. Most patients (56%) had resumed their physical activities at the same level as before the surgery. Signs of osteoarthritis were found in 26% of patients (16% were Ahlback stage 1 and 10% were stage 2). There was only one graft failure. These good outcomes are consistent with other published studies on combined ACL-LET. There was neither significant stiffness, nor a higher rate of secondary osteoarthritis relative to ACL reconstruction only, particularly in the lateral tibiofemoral compartment.

CONCLUSION

Adding primary LET to ACL reconstruction improves control of rotational laxity over time without increasing the complication rate.

LEVEL OF EVIDENCE

IV, retrospective study without control group.

Implementation of Endogenous and Exogenous Mesenchymal Progenitor Cells for Skeletal Tissue Regeneration and Repair

Harnessing adult mesenchymal stem/progenitor cells to stimulate skeletal tissue repair is a strategy that is being actively investigated. While scientists continue to develop creative and thoughtful ways to utilize these cells for tissue repair, the vast majority of these methodologies can ultimately be categorized into two main approaches: (1) Facilitating the recruitment of endogenous host cells to the injury site; and (2) physically administering into the injury site cells themselves, exogenously, either by autologous or allogeneic implantation. The aim of this paper is to comprehensively review recent key literature on the use of these two approaches in stimulating healing and repair of different skeletal tissues. As expected, each of the two strategies have their own advantages and limitations (which we describe), especially when considering the diverse microenvironments of different skeletal tissues like bone, tendon/ligament, and cartilage/fibrocartilage. This paper also discusses stem/progenitor cells commonly used for repairing different skeletal tissues, and it lists ongoing clinical trials that have risen from the implementation of these cells and strategies. Lastly, we discuss our own thoughts on where the field is headed in the near future.

Young age, female gender, Caucasian race, and workers' compensation claim are risk factors for reoperation following arthroscopic ACL reconstruction

PURPOSE

Given the increasing incidence of arthroscopic anterior cruciate ligament reconstruction (ACLR), mid- to long-term rates of reoperations were investigated on the ipsilateral knee following ACLR.

METHODS

New York Statewide Planning and Research Cooperative Systems (SPARCS) database was queried from 2003 to 2012 to identify patients with a primary ICD-9 diagnosis for ACL tear and concomitant CPT code for ACLR. Patients were longitudinally followed for at least 2 years to determine incidence and nature of subsequent ipsilateral knee procedures.

RESULTS

The inclusion criteria were met by 45,231 patients who had undergone ACLR between 2003 and 2012. Mean age was found to be 29.7 years (SD 11.6). Subsequent ipsilateral outpatient knee surgery after a mean of 25.7 ± 24.5 months was performed in 10.7% of patients. Revision ACLR was performed for nearly one-third of reoperations. Meniscal pathology was addressed in 58% of subsequent procedures. Age 19 or younger, female gender, worker's compensation (WC) insurance, and Caucasian race were identified as independent risk factors for any ipsilateral reoperation. An initial isolated ACLR and initial ACLR performed by a high-volume surgeon were found to be independently associated with lower reoperation rates. Tobacco use was not significant. Survival rates of 93.4%, 89.8% and 86.7% at 2-, 5- and 10 years, respectively, were found for any ipsilateral reoperation.

CONCLUSION

A 10.7% ipsilateral reoperation rate at an average of 25.9 (SD 24.5) months after ACLR and an overall ACLR revision rate of 3.1% were demonstrated by the analysis. Meniscal pathology was addressed in the majority of subsequent interventions. Age 19 or younger, female gender, Caucasian race, and WC claim were associated with reoperation. Initial isolated ACLR and procedure performed by high-volume surgeon were associated with reduced reoperation.

LEVEL OF EVIDENCE

Level III.

Tendon and Ligament Healing and Current Approaches to Tendon and Ligament Regeneration

Ligament and tendon injuries are common problems in orthopedics. There is a need for treatments that can expedite nonoperative healing or improve the efficacy of surgical repair or reconstruction of ligaments and tendons. Successful biologically-based attempts at repair and reconstruction would require a thorough understanding of normal tendon and ligament healing. The inflammatory, proliferative, and remodeling phases, and the cells involved in tendon and ligament healing will be reviewed. Then, current research efforts focusing on biologically-based treatments of ligament and tendon injuries will be summarized, with a focus on stem cells endogenous to tendons and ligaments. Statement of clinical significance: This paper details mechanisms of ligament and tendon healing, as well as attempts to apply stem cells to ligament and tendon healing. Understanding of these topics could lead to more efficacious therapies to treat ligament and tendon injuries. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:7-12, 2020.

Paradoxical tunnel enlargement after ACL reconstruction with hamstring autografts when using β-TCP containing interference screws for tibial aperture fixation- prospectively comparative study

BACKGROUND

Tibial aperture fixation with a bioabsorbable interference screw is a popular fixation method in anterior cruciate ligament reconstruction (ACLR). An interference screw containing β-tricalcium phosphate (β-TCP) to improve bony integration and biocompatibility was recently introduced. This study aims to compare the clinical outcomes and radiological results of tunnel enlargement effect between the 2 bioabsorbable fixative devices of pure poly-L-lactic acid (PLLA) interference screws and β-TCP-containing screws, for tibial interference fixation in ACLR using hamstring autografts.

METHODS

Eighty consecutive patients who had undergone double-bundle ACLR between 2011 to 2012 were prospectively reviewed and randomly divided into two groups based on the type of tibial interference screw: 28 were assigned to the pure PLLA screw group (Group A), while the other 29 were assigned to the β-TCP-containing screw fixation group (Group B). Clinical evaluations and radiological analyses were conducted in both groups with a minimum 2- year follow-up.

RESULTS

There was no significant difference in subjective or objective clinical outcome between the 2 groups. In radiological analyses, the use of a β-TCP-containing screw reduced tunnel widening in the portion of the tunnel with screw engagement compared to the pure PLLA screw, while the use of a β-TCP-containing screw resulted in greater tunnel enlargement in the proximal portion of the tunnel without screw engagement than use of a pure PLLA screw.

CONCLUSION

Use of a β-TCP-containing interference screw in tibial aperture fixation reduced tunnel enlargement in the vicinity of the screw, whereas greater enlargement occurred proximal to the screw end relative to use of a pure PLLA interference screw. These paradoxical enlargements in use of β-TCP containing screws suggest that for reducing tunnel enlargement, the length of the interference screw should be as fit as possible with tunnel length in terms of using soft grafts.

LEVEL OF EVIDENCE

II, Prospectively comparative study.

TRIAL REGISTRATION

Retrospectively registered with ClinicalTrials.gov. (NCT02754674) , Date of trial registration: February 10, 2016.

The effect of anterior cruciate ligament graft rotation on knee biomechanics

PURPOSE

The purpose of this study was to evaluate the effects on knee biomechanics of rotating the distal end of the bone-patellar tendon graft 90° in anatomic single-bundle (SB) anterior cruciate ligament (ACL) reconstruction with a porcine model.

METHODS

Twenty (n = 20) porcine knees were evaluated using a robotic testing system. Two groups and three knee states were compared: (1) intact ACL, (2) deficient ACL and (3) anatomic SB ACL reconstruction with (a) non-rotated graft or (b) rotated graft (anatomic external fibre rotation). Anterior tibial translation (ATT), internal (IR) and external rotation (ER) and the in situ tissue force were measured under an 89-N anterior tibial (AT) load and 4-N m internal and external tibial torques.

RESULTS

A significant difference from the intact ACL was found in ATT at 60° and 90° of knee flexion for rotated and non-rotated graft reconstructions (p < 0.05). There was a significant difference in the in situ force from the intact ACL with AT loading for rotated and non-rotated graft reconstructions at 60° and 90° of knee flexion (p < 0.05). Under IR loading, the in situ force was significantly different from the intact ACL at 30° and 60° of knee flexion for rotated and non-rotated graft reconstructions (p < 0.05). There were no significant differences in ATT, IR, ER and the in situ force between rotated and non-rotated reconstructions.

CONCLUSION

Graft rotation can be used with anatomic SB ACL reconstruction and not have a deleterious effect on knee anterior and rotational biomechanics. This study has clinical relevance in regard to the use of graft rotation to better reproduce the native ACL fibre orientation in ACL reconstruction.

* Hierarchically Structured Electrospun Scaffolds with Chemically Conjugated Growth Factor for Ligament Tissue Engineering

The anterior cruciate ligament (ACL) of the knee is vital for proper joint function and is commonly ruptured during sports injuries or car accidents. Due to a lack of intrinsic healing capacity and drawbacks with allografts and autografts, there is a need for a tissue-engineered ACL replacement. Our group has previously used aligned sheets of electrospun polycaprolactone nanofibers to develop solid cylindrical bundles of longitudinally aligned nanofibers. We have shown that these nanofiber bundles support cell proliferation and elongation and the hierarchical structure and material properties are similar to the native human ACL. It is possible to combine multiple nanofiber bundles to create a scaffold that attempts to mimic the macroscale structure of the ACL. The goal of this work was to develop a hierarchical bioactive scaffold for ligament tissue engineering using connective tissue growth factor (CTGF)-conjugated nanofiber bundles and evaluate the behavior of mesenchymal stem cells (MSCs) on these scaffolds in vitro and in vivo. CTGF was immobilized onto the surface of individual nanofiber bundles or scaffolds consisting of multiple nanofiber bundles. The conjugation efficiency and the release of conjugated CTGF were assessed using X-ray photoelectron spectroscopy, assays, and immunofluorescence staining. Scaffolds were seeded with MSCs and maintained in vitro for 7 days (individual nanofiber bundles), in vitro for 21 days (scaled-up scaffolds of 20 nanofiber bundles), or in vivo for 6 weeks (small scaffolds of 4 nanofiber bundles), and ligament-specific tissue formation was assessed in comparison to non-CTGF-conjugated control scaffolds. Results showed that CTGF conjugation encouraged cell proliferation and ligament-specific tissue formation in vitro and in vivo. The results suggest that hierarchical electrospun nanofiber bundles conjugated with CTGF are a scalable and bioactive scaffold for ACL tissue engineering.

Mid-Term Outcomes of Anterior Cruciate Ligament Reconstruction with Far Anteromedial Portal Technique

Purpose

The purpose of this study was to evaluate the mid-term outcomes of anatomic anterior cruciate ligament (ACL) reconstruction using two anteromedial (AM) portals by comparing with short-term follow-up results.

Materials and Methods

Fifty patients who were treated by ACL reconstruction using a two AM portal technique were evaluated retrospectively. The follow-up period was at least 5 years. The mean follow-up period was 68.5±13.9 months. The mid-term clinical outcomes were compared with short-term (≥12 months) results. For the assessment of knee stability, anterior tibial translation was evaluated using the Lachman test and the KT-2000. Rotational stability was evaluated using pivot shift test. For clinical assessment, the Lysholm and International Knee Documentation Committee scores were used.

Results

The average anterior translation was 2.1±1.4 mm at the short-term follow-up and 2.8±1.8 mm at the mid-term follow-up. Stability and midterm clinical outcomes were not significantly improved compared to the short-term follow-up results. At the mid-term follow-up, anteroposterior (AP) instability assessed by the KT-2000 was slightly increased, but still acceptable. On the other clinical physical evaluation, there was no statistically significant difference.

Conclusions

The short-term and mid-term outcomes of ACL reconstruction using the two AM portal technique were not significantly different except for AP stability although the value was less than 3 mm at both follow-ups. Therefore, this operative technique could be considered a satisfactory alternative for ACL reconstruction.

Femoral Tunnel Positioning in Anterior Cruciate Ligament Reconstruction: Anteromedial Portal versus Transtibial Technique-A Randomized Clinical Trial

Purpose  The purpose of this study was to investigate, through three-dimensional computed tomography (3D-CT), the accuracy of femoral tunnel positioning in patients undergoing anterior cruciate ligament (ACL) reconstruction, comparing transtibial (TT) and anteromedial (AM) techniques. Methods  We evaluated postoperative 3D-CT scans of 26 patients treated with ACL reconstruction with hamstrings autograft using a low accessory AM portal technique and 26 treated with the TT technique. The position of the femoral tunnel center was measured with the quadrant method. Results  Using quadrant method on CT scans, femoral tunnels were measured at a mean of 32.2 and 28.1% from the proximal condylar surface (parallel to Blumensaat line) and at a mean of 31.2 and 15.1% from the notch roof (perpendicular to Blumensaat line) for the AM and TT techniques, respectively. Conclusion  The AM portal technique provides more anatomical graft placement than TT techniques. Level of Evidence  Level I, randomized clinical study.

Autograft Versus Allograft Anterior Cruciate Ligament Reconstruction: A Prospective, Randomized Clinical Study With a Minimum 10-Year Follow-up

BACKGROUND

The use of allografts for anterior cruciate ligament (ACL) reconstruction in young athletes is controversial. No long-term results have been published comparing tibialis posterior allografts to hamstring autografts.

PURPOSE

To evaluate the long-term results of primary ACL reconstruction using either an allograft or autograft.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

From June 2002 to August 2003, patients with a symptomatic ACL-deficient knee were randomized to receive either a hamstring autograft or tibialis posterior allograft. All allografts were from a single tissue bank, aseptically processed, and fresh-frozen without terminal irradiation. Graft fixation was identical in all knees. All patients followed the same postoperative rehabilitation protocol, which was blinded to the therapists. Preoperative and postoperative assessments were performed via examination and/or telephone and Internet-based questionnaire to ascertain the functional and subjective status using established knee metrics. The primary outcome measures were graft integrity, subjective knee stability, and functional status.

RESULTS

There were 99 patients (100 knees); 86 were men, and 95% were active-duty military. Both groups were similar in demographics and preoperative activity level. The mean and median ages of both groups were identical at 29 and 26 years, respectively. Concomitant meniscal and chondral pathologic abnormalities, microfracture, and meniscal repair performed at the time of reconstruction were similar in both groups. At a minimum of 10 years (range, 120-132 months) from surgery, 96 patients (97 knees) were contacted (2 patients were deceased, and 1 was unable to be located). There were 4 (8.3%) autograft and 13 (26.5%) allograft failures that required revision reconstruction. In the remaining patients whose graft was intact, there was no difference in the mean Single Assessment Numeric Evaluation, Tegner, or International Knee Documentation Committee scores.

CONCLUSION

At a minimum of 10 years after ACL reconstruction in a young athletic population, over 80% of all grafts were intact and had maintained stability. However, those patients who had an allograft failed at a rate over 3 times higher than those with an autograft.

Anatomic Single Bundle Anterior Cruciate Ligament Reconstruction by Low Accessory Anteromedial Portal Technique: An In Vivo 3D CT Study

Purpose

Proper femoral tunnel position is important for anatomical reconstruction of the anterior cruciate ligament (ACL). The purpose of this study was to evaluate the positions of femoral and tibial tunnels created using an accessory anteromedial portal technique in single bundle ACL reconstruction.

Materials and Methods

The femoral tunnel was targeted at the mid-portion of the ACL bundles. We evaluated postoperative computed tomography scans of 32 patients treated by ACL reconstruction using a free-hand low accessory anteromedial portal technique. On the tibial side, the tunnel position was evaluated using Tsukada's method. On the femoral side, the position was evaluated using 1) the quadrant method, 2) Mochizuki's method, 3) Mochizuki's method, and 4) Takahashi's method. Tunnel obliquity was also evaluated.

Results

The mean tibial tunnel position was located at 44.6%±2.5% anterior from the anterior margin and 48.0%±3.0% in medial from the medial margin. The mean femoral tunnel position was located at the center between the anteromedial and posterolateral bundles: Quadrant method, 26.7%±2.7%/30.0%±2.9%; Watanabe's method, 37.7%±2.5%/26.6%±2.2%; Mochizuki's method, 38.7%±2.7%; Takahashi's method, 21.8%±2.2%. The mean femoral tunnel obliquity was 57.7°±6.2° in the sagittal plane and 49.9°±5.6° in the coronal plane.

Conclusions

In anatomic single bundle ACL reconstruction, the low anteromedial portal technique can restore accurate position of the native footprint. Accurate femoral tunnel position facilitates recovery of stability and decreases graft failure rate.

Patellar tendon autograft reconstruction of the anterior cruciate ligament with and without lateral plasty in advanced-stage chronic laxity. A clinical, prospective, randomized, single-blind study using passive dynamic X-rays

PURPOSE

A prospective randomized study was performed to assess the influence of extra-articular ilio-tibial band tenodesis on the results of arthroscopic anterior cruciate ligament (ACL) reconstruction in patients with advanced-stage chronic anterior laxity of the knee.

METHODS

Preoperatively, the two constituent groups of our series of 120 patients: group 1 (Kenneth Jones) and group 2 (Kenneth Jones+extra-articular ilio-tibial band tenodesis) were strictly comparable with regard to demographic data, activity level, interval between the injury and the operation, and even objective laxity. Through radiological measurements made by passive dynamic X-rays, we studied the evolution of the objective laxity on the two compartments (medial and lateral) of the knee before the surgery and in review.

RESULTS

At 2 years follow-up, there was no significant difference between the two groups in terms of the subjective result, sports, and the overall international knee documentation committee score, however, In terms of objective laxity; Gain laxity obtained after surgery on the lateral compartment, was statistically higher in cases of extra-articular associated plasty (+29%), by cons in cases of intra-articular reconstruction alone, the laxity of the lateral compartment was poorly controlled and has continued to evolve despite the plasty of the ACL.

CONCLUSION

The indication of an associated extra-articular plasty remains very discussed but we plead for an objective criterion with knowing the importance of preoperative objective laxity especially that of the lateral compartment to decide if it necessary, or not, being associated.

LEVEL OF EVIDENCE

Level I, therapeutic prospective randomized trial.

Hamstring tendons insertion - an anatomical study

Objective

To study the anatomy of the hamstring tendons insertion and anatomical relationships.

Methods

Ten cadaver knees with medial and anterior intact structures were selected. The dissection was performed from anteromedial access to exposure of the insertion of the flexor tendons (FT), tibial plateau (TP) and tibial tuberosity (TT). A needle of 40 × 12 and a caliper were used to measure the distance of the tibial plateau of the knee flexor tendons insertion at 15 mm from the medial border of the patellar tendon and tibial tuberosity to the insertion of the flexor tendons of the knee. The angle between tibial plateau and the insertion of the flexor tendons of the knee (A-TP-FT) was calculated using Image Pro Plus software.

Results

The mean distance TP-FT was 41 ± 4.6 mm. The distance between the TT-FT was 6.88 ± 1 mm. The (A-TP-FT) was 20.3 ± 4.9°.

Conclusion

In the anterior tibial flexor tendons are about 40 mm from the plateau with an average of 20°.

Bony incorporation of soft tissue anterior cruciate ligament grafts in an animal model: autograft versus allograft with low-dose gamma irradiation

BACKGROUND

The effect of low-dose gamma irradiation on healing of soft tissue allografts remains largely unknown.

HYPOTHESIS

The authors hypothesized that soft tissue allograft healing to bone would be delayed compared with that of autograft tissue and that low-dose (1.2 Mrad) gamma irradiation would not affect the healing response of allograft tissue after anterior cruciate ligament (ACL) reconstruction.

STUDY DESIGN

Controlled laboratory study.

METHODS

Forty-eight New Zealand White rabbits underwent bilateral ACL reconstructions with semitendinosus tendon graft. Sixteen rabbits were reconstructed with autografts and the remainder with allografts. The 32 allograft rabbits each received 1 irradiated allograft (1.2 Mrad), with the contralateral leg receiving a nonirradiated allograft. Animals were euthanized at 2 weeks or 8 weeks postoperatively. Tensile stiffness, maximum load, and displacement at maximum load were measured. Tibial and femoral segments were sectioned perpendicular to the tunnel axis allowing for histologic and histomorphometric analyses at the tendon-bone interface.

RESULTS

There were no significant differences between the maximum load or stiffness values among all groups at 8 weeks. At 2 weeks, autograft exhibited significantly (P < .01) lower maximum load than did the nonirradiated grafts. Regarding histology, at both 2- and 8-week time points, autograft tendon displayed more advanced degenerative and remodeling processes in comparison with irradiated allograft and nonirradiated allograft.

DISCUSSION

The maximum load and stiffness of a healing tendon allograft in ACL reconstruction appear to be unaltered by low-dose (1.2 Mrad) irradiation. At 8 weeks, there were no biomechanical differences in tendon-bone healing of allografts when compared with autograft controls. Histologic analyses suggested a faster remodeling response in autograft specimens in comparison with allografts at both time points.

CLINICAL RELEVANCE

The findings support the contention that low-dose gamma irradiation is safe for sterilization of ACL soft tissue allografts without compromise of graft properties at early time points.

Femoral press-fit fixation in ACL reconstruction using bone-patellar tendon-bone autograft: results at 15 years follow-up

Background

If anterior cruciate ligament (ACL) reconstruction is to be performed, decision regarding graft choice and its fixation remains one of the most controversial. Multiple techniques for ACL reconstruction are available. To avoid disadvantages related to fixation devices, a hardware-free, press-fit ACL reconstruction technique was developed.

The aim of this study was to evaluate clinical outcome and osteoarthritis progression in long term after ACL reconstruction with central third patellar-tendon autograft fixed to femur by press-fit technique.

Methods

Fifty two patients met inclusion/excusion criteria for this study. The patients were assessed preoperatively and at 15 years after surgery with International Knee Documentation Committee Knee Ligament Evaluation Form, Lysholm knee score, Tegner activity scale and radiographs.

Results

Good overall clinical outcomes and self-reported assessments were documented, and remained good at 15 years. The mean Lysholm and Tegner scores improved from 59.7 ± 18.5 and 4.2 ± 1.0 preoperatively to 86.4 ± 5.6 (p = 0.004) and 6.9 ± 1.4 (p = 0.005) respectively at follow-up. The IKDC subjective score improved from 60.1 ± 9.2 to 80.2 ± 8.1 (p = 0.003).

According to IKDC objective score, 75% of patients had normal or nearly normal knee joints at follow-up. Grade 0 or 1 results were seen in 85% of patients on laxity testing. Degenerative changes were found in 67% of patients. There was no correlation between arthritic changes and stability of knee and subjective evaluation (p > 0.05).

Conclusions

ACL reconstruction with patellar tendon autograft fixed to femur with press-fit technique allows to achieve good self-reported assessments and clinical ligament evaluation up to 15 years. Advantages of the bone-patellar-tendon-bone (BPTB) press-fit fixation include unlimited bone-to-bone healing, cost effectiveness, avoidance of disadvantages associated with hardware, and ease for revision surgery. BPTB femoral press-fit fixation technique can be safely applied in clinical practice and enables patients to return to preinjury activities including high-risk sports.

Delta screw versus RetroScrew tibial fixation for ACL reconstruction

PURPOSE

The purpose of this study is to determine whether the RetroScrew tibial fixation system offers a biomechanical advantage over the Delta screw for anterior cruciate ligament (ACL) reconstruction in cadaveric tibias with low bone mineral density (BMD).

METHODS

Ten matched pairs of osteoporotic cadaveric tibiae underwent simulated ACL reconstruction using quadrupled hamstring grafts with one of the two tibial fixation constructs. Group 1 was fixed with the Delta screw (DS; 35-mm antegrade biointerference screw), and group 2 was fixed with the RetroScrew system (RSS; 20-mm retrograde and 17-mm antegrade biointerference screws). Each construct was cyclically loaded (50-200 N, 1 Hz, 500 cycles) and subsequently loaded to failure (20 mm/s).

RESULTS

All specimens were osteoporotic without significant segmental (proximal, middle, and distal) BMD differences between groups by quantitative computed tomography (P = n.s.). A trend was noted for more construct failures due to graft slippage in the DS group (n = 3) over the RSS group (n = 1). There were no significant differences in cyclic displacement (P = n.s.), maximum cyclic stiffness (P = n.s.), maximum load at failure (P = n.s.), or pullout stiffness (P = n.s.) between groups.

CONCLUSIONS

In an osteoporotic cadaveric model, there was no significant biomechanical advantage of the RetroScrew system versus the Delta screw for tibial fixation in soft tissue graft ACL reconstruction. However, a trend toward lower graft fixation failure to cyclic loading was noted with the RetroScrew system.

Anatomic single bundle anterior cruciate ligament reconstruction by the two anteromedial portal method: the comparison of transportal and transtibial techniques

Purpose

The purpose of this study was to report the results of anatomic single bundle anterior cruciate ligament (ACL) reconstruction by the two anteromedial portal method.

Materials and Methods

We evaluated the clinical results in 33 patients with ACL rupture who were treated by anatomic ACL reconstruction using the two anteromedial portal technique. The control group included 33 patients with ACL rupture who were treated with the conventional transtibial non-anatomic method. We performed an objective instability test, both preoperatively and at the final follow-up. We also compared the clinical results of both groups using International Knee Documentation Committee and Lysholm scores as a subjective test.

Results

At the final follow up, the study showed that in the control group, the Lachman test was negative in 27 cases (81.8%), the pivot shift test was negative in 26 cases (78.8%), and the average anterior translocation was 3.1 mm on a KT-2000 arthrometer. In the group of patients who underwent anatomic reconstruction by the two anteromedial portal method, the Lachman test was negative in 28 cases (84.8%), the pivot shift test was negative in 30 cases (90.9%), and the average anterior translocation was 2.8 mm on the KT-2000 arthrometer. Results in the pivot shift showed statistically significant improvement compared to the control group.

Conclusions

Anatomic ACL reconstruction by two anteromedial portals is an effective surgical technique that restores the rotational stability with excellent clinical results.

Anatomic single- and double-bundle anterior cruciate ligament reconstruction, part 2: clinical application of surgical technique

The anterior cruciate ligament has been and is of great interest to scientists and orthopaedic surgeons worldwide. Anterior cruciate ligament reconstruction was initially performed using an open approach. When the approach changed from open to arthroscopic reconstruction, a 2- and, later, 1-incision technique was applied. With time, researchers found that traditional arthroscopic single-bundle reconstruction did not fully restore rotational stability of the knee joint and a more anatomic approach to reconstruct the anterior cruciate ligament has been proposed. Anatomic anterior cruciate ligament reconstruction intends to replicate normal anatomy, restore normal kinematics, and protect long-term knee health. Although double-bundle anterior cruciate ligament reconstruction has been shown to result in better rotational stability in both biomechanical and clinical studies, it is vital to differentiate between anatomic and double-bundle anterior cruciate ligament reconstruction. The latter is merely a step closer to reproducing the native anatomy of the anterior cruciate ligament; however, it can still be done nonanatomically. To evaluate the potential benefits of reconstructing the anterior cruciate ligament in an anatomic fashion, accurate, precise, and reliable outcome measures are needed. These include, for example, T2 magnetic resonance imaging mapping of cartilage and quantification of graft healing on magnetic resonance imaging. Furthermore, there is a need for a consensus on which patient-reported outcome measures should be used to facilitate homogeneous reporting of outcomes.

Anterior cruciate ligament reconstruction using remnant preservation and a femoral tensioning technique: clinical and magnetic resonance imaging results

PURPOSE

The purpose of this study was to investigate the clinical and magnetic resonance imaging (MRI) results of anterior cruciate ligament (ACL) reconstruction with autogenous hamstring tendon by use of remnant preservation and a femoral tensioning technique.

METHODS

A total of 53 patients who had ACL reconstruction by use of remnant ACL stump preservation and a femoral tensioning technique were evaluated. Clinical evaluation at a minimum of 2 years after surgery included range of motion, Lachman test, pivot-shift test, KT-2000 arthrometer testing (MEDmetric, San Diego, CA), and clinical scores. Plain radiographs were evaluated for tunnel enlargement. MRI was obtained for evaluation of graft continuity, cyclops-like mass lesion, and positioning of the tibial tunnel. Second-look arthroscopy was performed in 33 patients.

RESULTS

The clinical scores improved postoperatively. There were statistically significant differences between preoperative and postoperative Lachman tests, pivot-shift tests, and KT-2000 arthrometer measurements. Postoperative MRI was available in 48 patients, and it showed intact graft in 45 patients, 2 partial tears, and 1 complete loss of graft. There were cyclops-like mass lesions in 12 patients, but none showed an extension limitation or pain at extension. The position of the tibial tunnel on the sagittal and coronal view was similar to the position of the normal ACL tibial insertion. The measured tibial tunnel widening on the radiographs at final follow-up was 2.2 ± 1.5 mm.

CONCLUSIONS

Reconstruction of the ACL by use of preservation and femoral tensioning of the remnant tissue showed good clinical results without increased concerns regarding incorrect tunnel formation. Postoperative MRI showed an increased incidence of cyclops-like mass lesions, but no clinical significance was observed.

LEVEL OF EVIDENCE

Level IV, case series.

Anterior cruciate ligament reconstruction using the medial third of the patellar tendon

PURPOSE

To evaluate the mid-term outcome of anterior cruciate ligament (ACL) reconstruction using the medial third of the patellar tendon as the bone-patellar tendon-bone (BPTB) graft.

METHODS

79 men (34 right knees and 45 left knees) aged 20 to 52 (mean, 28) years underwent ACL reconstruction using the medial third of the patellar tendon with bone plugs and were followed up for a minimum of 3 years. Stability was assessed using the Lachman test and the pivot shift test. The range of motion, donor-site symptoms, Lysholm knee score, and International Knee Documentation Committee (IKDC) score were also recorded.

RESULTS

In terms of stability, only 4 patients had a grade-2 laxity postoperatively, compared to all having a grade-2 or -3 laxity preoperatively. Regarding the range of motion, extension loss was <3º in 76 patients and 3º to 5º in 3, whereas flexion loss was <5º in 73 patients, 5º to 15º in 5, and 16º to 25º in one. No patient had patellar tendon rupture/shortening, patellar fracture, or patellar maltracking. The mean Lysholm knee score improved from 48 to 92 (p<0.0001); scores were excellent (>90) in 46 patients and good (83-90) in 32 patients. The overall IKDC score was grade A (normal) in 9 patients, grade B (near normal) in 66, and grade C (abnormal) in 4. Three of the latter patients had osteoarthritic changes and pain on minimal physical activity. Only one patient had a sensation of partial giving way during moderate physical activity. 20% of the patients had anterior knee pain.

CONCLUSION

Outcome of ACL reconstruction using the medial third of the patellar tendon was comparable to that using the central third of the patellar tendon. In addition, there were no instances of patellar tendon rupture/shortening, patellar fracture, or patellar maltracking.

ACL reconstruction with "the original all-inside technique"

With the improvement of knee arthroscopy during the past decades anterior cruciate ligament reconstruction has become a common procedure, with several surgical techniques described. The "original all-inside technique" for ACL reconstruction with manually drilled double half tunnels, allowing the use of one single tendon triplicated or quadruplicated and hopefully improving the quality of the contact area between graft and bone.

A comparison of the results of anterior cruciate ligament reconstruction using bioabsorbable versus metal interference screws: a meta-analysis

BACKGROUND

Graft fixation during anterior cruciate ligament (ACL) reconstruction can be achieved with use of either bioabsorbable screws or metal screws. Although bioabsorbable screws and metal screws have similar fixation strengths, bioabsorbable screws eliminate the need for removal. In addition, postoperative imaging is easier to interpret when bioabsorbable screws are used. Bioabsorbable screws may be associated with an increased inflammatory response, an increased risk of screw breakage, incomplete screw absorption, or tunnel widening. We investigated the outcomes associated with the use of bioabsorbable screws as compared with metal screws for ACL reconstruction. Our hypothesis was that there is no significant difference in outcomes between these screw types for ACL reconstruction.

METHODS

We systematically searched electronic databases to identify randomized controlled trials in which bioabsorbable screws were compared with metal screws for ACL reconstruction. Therapeutic studies with a minimum twelve-month mean follow-up were considered for inclusion. Clinical outcomes (International Knee Documentation Committee [IKDC], Lysholm, Tegner activity scores), laxity testing, and reported complications were evaluated in the meta-analysis. Additionally, imaging assessment of tunnel widening was evaluated.

RESULTS

Eight studies matched the inclusion criteria. These studies comprised a total of 745 patients undergoing ACL reconstruction (including 378 patients managed with bioabsorbable screws and 367 patients managed with metal screws). No significant differences were identified between the two screw types with respect to IKDC, Lysholm, or Tegner activity scores or with respect to the results of laxity testing with arthrometry. The complication rates were also statistically similar in the two groups. The variability in imaging assessment of tunnel widening among the studies precluded meta-analysis.

CONCLUSIONS

The clinical results associated with bioabsorbable screws and metal screws are statistically similar. Laxity evaluation demonstrated no significant differences between bioabsorbable screws and metal screws. The complication rates associated with bioabsorbable screws and metal screws were also similar. The results of this meta-analysis support the hypothesis that there are no significant differences in the outcomes associated with bioabsorbable screws as compared with metal screws for ACL reconstruction.

LEVEL OF EVIDENCE

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

Double-bundle ACL reconstruction demonstrated superior clinical stability to single-bundle ACL reconstruction: a matched-pairs analysis of instrumented tests of tibial anterior translation and internal rotation laxity

PURPOSE

To compare objective measures of in vivo joint laxity between patients treated with single-bundle (SB) or double-bundle (DB) anterior cruciate ligament (ACL) reconstructions.

METHODS

Sixty-four patients matched by age, height, weight, and that had undergone unilateral SB or DB hamstring ACL reconstruction participated in this study. Bilateral anterior tibial translation (ATT) was recorded using the KT1000 arthrometer, and a robotic testing system was used to assess side-to-side differences in rotational characteristics. Each reconstruction was evaluated to determine how well it mimicked the anteroposterior (AP) and rotational biomechanics of the normal knee. A reconstruction was defined as mimicking the normal knee if ATT and internal rotation (IR) were within 3 mm and 3.5°, respectively.

RESULTS

Side-to-side differences in ATT were significantly higher for the SB group (2.2 ± 1.4 mm) than the DB group (1.1 ± 1.0 mm, P = 0.001). While relative side-to-side differences in IR did not differ between the SB (1.3°) and DB groups (1.1°, P = 0.82), absolute IR differences were significantly less with the DB reconstruction (2.1° vs. 4.7°, P = 0.001). A significantly greater percentage of DB patients (81%, P = 0.0003) had both ATT and IR similar to the normal knee, compared to 34% of the SB patients; however, IKDC subjective scores did not differ between groups. Regardless of technique, patients with the greatest rotational laxity of their non-operative knee demonstrated significantly worse IKDC scores.

CONCLUSION

DB reconstruction resulted in reduced side-to-side differences in both ATT and IR. The DB technique more consistently reproduced the biomechanical profile of the uninjured limb than did the SB technique without increasing the risk of over-constraining the knee.

Anterior cruciate ligament reconstruction using achilles tendon allograft: an assessment of outcome for patients age 30 years and older

Achilles allografts have become popular for anterior cruciate ligament (ACL) reconstructions in older patients. Primary ACL reconstructions using Achilles tendon allografts in patients age 30 years and older are successful in restoring the knee to "normal" or "near normal." During a three-year period, the two senior authors performed 65 primary ACL reconstructions using Achilles tendon allografts in patients aged 30 years and older. Our exclusion criteria were periarticular fracture, ipsilateral/contralateral knee ligament injury, and previous or concomitant osteotomy or cartilage restoration procedure. Each patient was evaluated via physical examination, functional and arthrometric testing, and radiographic and subjective outcome. Knees were considered normal, near normal, or abnormal based on the International Knee Documentation Committee (IKDC) system. Forty-three patients were examined at an average of 33 months (minimum, 24 months) postoperatively. At the time of ACL reconstruction, 35% had normal articular cartilage in all three compartments and 70% had meniscal tears. No re-ruptures occurred. While 24% had mean maximal translation differences less than or equal to 3 mm, none had side-to-side differences greater than 5 mm. Postoperative IKDC, Activities of Daily Living, and Activity Rating Scale scores averaged 88, 94, and 7.7, respectively. Despite the overall favorable outcomes, 29% had worsened radiographic grades at follow-up. Using an Achilles allograft for ACL reconstruction in patients older than 30 years, we restored over 90% of knees to normal or near normal while limiting postoperative complications. Poor subjective results may be related less to instability and more to pain, which may result from progressive arthritis.

Hamstring antagonist torque generated in vivo following ACL rupture and ACL reconstruction

Hamstring motor behaviour and resultant antagonist torque during knee extension has been quantified in uninjured individuals however, the effect of ACL rupture and ACL reconstruction (ACLR) on the morphology of hamstring antagonist torque generated in vivo is unknown. The purpose of this cross-sectional study was to quantify the hamstring antagonist torque generated in vivo during isokinetic knee extension in ACLD and ACLR patients relative to uninjured control subjects. Ten male ACL deficient (ACLD) subjects (18-35 years), 14 matched males who had undergone ACLR using the bone-patellar tendon-bone graft and 22 matched male control subjects participated. We used a mathematical model to estimate the opposing torque generated by the hamstrings during isokinetic knee extension in 10 degrees intervals from 80 degrees to 10 degrees knee flexion. Control group hamstring antagonist torque was significantly lower at 80-70 degrees knee flexion compared with that of the ACLD (% Diff=40.2; p=0.019) and ACLR (% Diff=34.8; p=0.036) groups. For all subject groups, hamstring antagonist torque demonstrated a descending-ascending curve; decreasing significantly from 80-70 degrees to 50-40 degrees knee flexion (% Diff=40.8 to 63.3; p=<0.001 to 0.009) but then increasing significantly from 50-40 degrees to 20-10 degrees knee flexion (% Diff=37.6 to 59.0; p=<0.001 to 0.012). ACL status and therefore, the ACL-hamstring reflex has little effect on the magnitude of hamstring antagonist torque generated during quadriceps-induced knee joint loading. Capsular afferents are thought to dictate the hamstring torque profile which decreased then increased during knee extension to maintain dynamic joint stability.

Long-term follow-up of 24.5 years after intra-articular anterior cruciate ligament reconstruction with lateral extra-articular augmentation

BACKGROUND

Many studies have reported successful outcomes 10 to 15 years after ACL reconstruction. However, few authors report results at ultra long-term follow-up (more than 20 years of follow-up).

PURPOSE

The aim of this study was to determine how the status of the medial meniscus and the medial compartment articular cartilage observed at the time of ACL reconstruction affects results more than 24 years after surgery. This article examines long-term outcome of ACL reconstruction with extra-articular augmentation (procedure performed through a medial arthrotomy).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

One hundred of 148 patients reviewed at 11.5 years of follow-up could be reviewed at 24.5 years. Complete clinical and radiographic evaluation (International Knee Documentation Committee scale and Knee Injury and Osteoarthritis Outcome Score) was performed.

RESULTS

The radiographic International Knee Documentation Committee rating was as follows: grade A, 39%; grade B, 7%; grade C, 27%; and grade D, 27%. Onset of osteoarthritis was correlated with medial meniscal status and femoral chondral defects at time of surgery.

CONCLUSION

Total medial meniscectomy and articular cartilage damage were risk factors for osteoarthritis.

Failure rate of Achilles tendon allograft in primary anterior cruciate ligament reconstruction

PURPOSE

This study was performed to determine the failure rate of patients undergoing primary anterior cruciate ligament (ACL) reconstruction with an Achilles tendon allograft by a single surgeon with the same surgical technique, graft fixation, and postoperative rehabilitation. The Achilles tendon allograft was obtained from a single source.

METHODS

Of 158 patients who underwent primary ACL reconstruction with Achilles tendon allograft, 144 were followed up at a mean of 40 months. The mean age was 29.5 years at the time of surgery. Evaluation included a questionnaire at serial follow-up visits, physical examination, and return to play.

RESULTS

Of 144 patients, 8 (5.6%) sustained traumatic reruptures or had evidence of laxity failure. Patients were divided into 4 age groups: less than 18 years, 18 to 25 years, 26 to 40 years, and 41 years or greater. Failure rates of 8.7%, 8.8%, 5.7%, and 0%, respectively, were found. A chi(2) contingency test was performed comparing patients aged 25 years or younger and those aged over 25 years with a resulting P value of .5811. No statistically significant difference between the groups of failures was seen.

CONCLUSIONS

The results of our study show that the failure rate for freeze-dried Achilles tendon allograft in primary ACL reconstruction was 8 of 144 (5.6%). When these patients were followed up for a minimum of 24 months, we found failure rates of 8.7%, 8.8%, 5.7%, and 0% in those aged less than 18 years, 18 to 25 years, 26 to 40 years, and 41 years or older, respectively. No statistically significant difference between the groups of failures was seen.

LEVEL OF EVIDENCE

Level IV, case series.

Anterior cruciate ligament reconstruction with and without computer navigation: a clinical and magnetic resonance imaging evaluation 2 years after surgery

PURPOSE

The purpose of this study was to evaluate the benefits of computer navigation on tunnel placement during anterior cruciate ligament reconstruction.

METHODS

A prospective, randomized, controlled study comparing computer navigation with manual operation was performed between December 2003 and April 2004. We assigned 20 patients to the computer navigation group and 20 patients to the manual navigation group. Surgery was performed by use of a patellar tendon autograft with press-fit fixation. A lateral radiograph of the knee at maximum extension was used to determine the exact position of the tibial tunnel at 4 days postoperatively. Outcomes were evaluated with International Knee Documentation Committee 2000, Tegner, and Lysholm scoring. There was an additional magnetic resonance imaging (MRI) evaluation of tunnel placement and graft quality at the most recent follow-up, approximately 24 months after surgery.

RESULTS

The postoperative radiographs and 2-year postoperative MRI scans showed no differences between groups for tibial or femoral tunnel placement. In both groups the mean tibial tunnel placement was 46% of the maximal diameter of the tibia. There were no significant differences between groups for objective and subjective outcomes scoring. Although some qualitative differences existed between groups with respect to MRI graft appearance at 2 years, this had no correlation with overall results.

CONCLUSIONS

No significant differences were found between computer-assisted and manually navigated anterior cruciate ligament reconstruction with regard to tunnel placement and clinical results at a mean of 2 years postoperatively.

LEVEL OF EVIDENCE

Level I, randomized, single-blinded, controlled trial.

Morphology of knee extension torque-time curves following anterior cruciate ligament injury and reconstruction

BACKGROUND

Mechanical instability, neurosensory deficits, and/or modified coactivation strategies following anterior cruciate ligament injury and surgery might compromise the ability of the knee extensors to exert a precise force during isokinetic knee extension with maximal effort. The purpose of this study was to examine the effects of an anterior cruciate ligament deficiency and reconstruction on knee extensor torque-time curve smoothness and to elucidate its association with hamstring (antagonist) activation and physical performance.

METHODS

Thirteen subjects who had a unilateral deficiency of the anterior cruciate ligament, twenty-five matched subjects with a unilateral reconstructed anterior cruciate ligament, and thirty-three control subjects performed knee extension and flexion repetitions bilaterally with maximal effort at 180 degrees/sec on a Cybex dynamometer. For the subjects with a deficient or a reconstructed anterior cruciate ligament, hamstring activation was measured electromyographically. Physical performance was measured by requiring subjects to perform single-limb timed hopping on the involved limb.

RESULTS

In the subjects with a reconstructed or a deficient anterior cruciate ligament, wavelet-derived mean instantaneous frequency of the extensor torque-time curves was significantly (p < 0.001) higher in the involved limb than in the noninvolved limb and the limbs of the control subjects. Furthermore, for the subjects with a reconstructed or deficient anterior cruciate ligament, the mean instantaneous frequency of the extensor torque-time curves was positively associated with the level of hamstring antagonist activity (r = 0.580, p < 0.001) and with hopping performance (b = -0.943, p = 0.019), whereas isokinetic peak torque was not (b = -0.001, p = 0.797).

CONCLUSIONS

For individuals who have a deficient or a reconstructed anterior cruciate ligament, an increased frequency content of the knee extensor torque is not, as previously and commonly assumed, a deleterious manifestation of the neuromuscular system. Rather, our results suggest that torque smoothness reduces as hamstring activation increases-a positive neuromuscular adaptation that enhances joint stability and, hence, optimizes physical performance. Wavelet-derived measures of extensor torque smoothness may provide valuable clinical information regarding joint function that conventional isokinetic torque measures cannot.

Functional outcomes and health-related quality of life after robot-assisted anterior cruciate ligament reconstruction with patellar tendon grafts

During a short period of time, surgical robots had been propagated for automated tunnel placement in anterior cruciate ligament (ACL) reconstruction. Clinical outcome data are currently unavailable. Between 2000 and 2003, 152 patients underwent ACL replacement with the assistance of the Computer Assisted Surgical Planning and Robotics system (CASPAR, OrtoMaquet, Germany) at our hospital. After minimal invasive pin placement in both the tibia and femur, computed tomography was used to register anatomical landmarks and to plan graft tunnel alignment. The robot was used to drill tibial and femoral tunnels in an outside-in fashion according to pre-operative planning. There was one procedure-specific Serious Adverse Event (i.e., an intraoperative transection of the posterior cruciate ligament). After IRB approval, all patients were invited for a follow-up examination. Data from 100 patients (35 women, 65 men, mean age 35 [SD 11] years, median follow-up 61 [range 42-77] months) form the basis of this report. Side-to-side differences in anterior laxity were measured with the KT-1000 arthrometer. Patient-centered outcomes included the Lysholm-Score, the lower extremity functional scale (LEFS), and the Short Form 36 (SF36). The mean KT-1000 side-to-side difference was 0.89 [95% confidence interval (CI) 0.52-1.26] mm. Eight and five patients had a positive Lachman and pivot shift test, respectively. The Lysholm-Score averaged 86 (95% CI 83-89) points. Excellent, good, fair, and poor outcomes were reported by 38, 32, 20, and 10 patients. The LEFS averaged 85 (95% CI 82-88) points. The mean SF36 Physical Component Score was 48.4 (95% CI 46.5-50.3), indicating residual deficits compared to the population norm. All tibial graft tunnels did not cross the Blumensaat line, but were placed slightly anterior to the optimal center of 42% reported in previous studies. Compared to literature data, robot-assisted ACL reconstruction with BTB grafts may lead to higher knee stability, but poorer functional outcomes. The immense additional efforts with the procedure did not pay off in a benefit to patients.

Dynamic restraint capacity of the hamstring muscles has important functional implications after anterior cruciate ligament injury and anterior cruciate ligament reconstruction

OBJECTIVE

The purpose of this study was to investigate the relation between knee functionality of anterior cruciate ligament deficient (ACLD) and anterior cruciate ligament reconstruction (ACLR) patients and hamstring antagonist torque generated during resisted knee extension.

DESIGN

Cross-sectional.

SETTING

Laboratory based.

PARTICIPANTS

Male ACLD subjects (n=10) (18-35 y) and 27 matched males who had undergone ACLR (14 patella tendon [PT] grafts and 13 combined semitendinosus/gracilis tendon grafts).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Knee functionality was rated (0- to 100-point scale) by using the Cincinnati Knee Rating System. Using electromyography data from the semitendinosus (ST) and biceps femoris muscles, we created a mathematical model to estimate the opposing torque generated by the hamstrings during isokinetic knee extension in 10 degrees intervals from 80 degrees to 10 degrees knee flexion.

RESULTS

Pearson product-moment correlations revealed that more functional ACLD subjects generated significantly (P<.05) higher hamstring antagonist torque throughout knee extension. In contrast, more functional PT subjects produced significantly lower hamstring antagonist torque at 80 degrees to 70 degrees knee flexion, whereas no significant associations were found between hamstring antagonist torque and knee functionality for the ST/gracilis tendon subjects.

CONCLUSIONS

An increased hamstring antagonist torque generated by the more functional ACLD subjects, reflective of increased hamstring contractile force, is thought to represent a protective mechanism to compensate for mechanical instability. The restoration of anterior knee stability through ACLR negates the need for augmented hamstring antagonist torque.

Anterior-posterior and rotatory stability of single and double-bundle anterior cruciate ligament reconstructions

BACKGROUND

Some surgeons presently reconstruct both the anteromedial and posterolateral bundles of the anterior cruciate ligament. The purposes of this study were to measure the abilities of single-bundle and anatomic double-bundle reconstructions to restore anteroposterior laxities and rotational kinematics to intact knee levels and to compare graft forces in reconstructed knees with forces in the native anterior cruciate ligament for the same loading conditions.

METHODS

Native anterior cruciate ligament force and tibial rotations were recorded during passive knee extension tests with and without applied tibial loads. The anteromedial and posterolateral bundles were reconstructed with patellar tendon tissue sized to fit tightly within 7-mm femoral tunnels. Testing was repeated with the anteromedial graft alone (single bundle), tensioned to restore anteroposterior laxity at 30 degrees of flexion, and with double-bundle grafts. For double-bundle reconstructions, the anteromedial graft was first tensioned as above and then the posterolateral graft was tensioned with use of one of four protocols: posterolateral tension = anteromedial tension at 10 degrees (DB1), posterolateral tension = anteromedial tension at 30 degrees (DB2), posterolateral tension = (anteromedial tension + 30 N) at 10 degrees (DB3), and posterolateral tension = (anteromedial tension + 30 N) at 30 degrees (DB4).

RESULTS

The posterolateral graft underwent a greater length change than the anteromedial graft between 0 degrees and 90 degrees . This difference in elongation patterns produced high forces in the posterolateral graft at 0 degrees when both grafts were tensioned and fixed at 30 degrees . The mean laxities for single-bundle reconstructions were within 1.1 mm of those of the intact knee between 0 degrees and 90 degrees ; the mean graft force at 0 degrees was 76 N. The mean laxities for DB4 reconstructions were from 0.9 to 2.8 mm less than those of the intact knee, and the mean graft force at 0 degrees was 264 N. Coupled internal tibial rotations from valgus moment were normal with the single-bundle graft. Internal rotations from tibial torque were approximately 2 degrees to 4 degrees greater than normal with a single-bundle graft. DB3 and DB4 reconstructions overcorrected the coupled tibial rotations from valgus moment and restored tibial rotations from internal torque to normal from 0 degrees to 45 degrees . The graft forces from tibial torque and valgus moment were normal with the single-bundle graft. The mean double-bundle graft forces at 0 degrees were 57 N to 143 N and 34 N to 171 N greater than normal for internal torque and valgus moment, respectively.

CONCLUSIONS

The single-bundle reconstruction produced graft forces, knee laxities, and coupled tibial rotations that were closest to normal. Adding a posterolateral graft to an anteromedial graft tended to reduce laxities and tibial rotations, but the reductions were accompanied by markedly higher forces in the posterolateral graft near 0 degrees that occasionally caused it to fail during tests with internal torque or anterior tibial force.

Reconstruction of the anterior cruciate ligament in patients over 50 years

The records of patients aged 50 years or over who underwent primary reconstruction of the anterior cruciate ligament between 1990 and 2002 were reviewed. There were 35 knees in 34 patients that met the inclusion criteria. The mean age of the patients was 57 years (50 to 66) and the mean clinical follow-up was for 72 months (25 to 173). A total of 23 knees were reconstructed with patellar tendon allograft, and 12 with patellar tendon autograft. The mean pre-operative knee extension was 1 degrees (-5 degrees to 10 degrees) and flexion was 129 degrees (125 degrees to 150 degrees) and at follow-up these values were 0 degrees (-5 degrees to 5 degrees) and 135 degrees (120 degrees to 150 degrees), respectively. Pre-operatively there were 31 knees (89%) with a Lachman grade 2+ or 3+. Post-operatively, 33 knees (94%) were Lachman grade 0 or 1+. The mean pre- and post-operative International Knee Documentation Committee scores were 39 (23 to 72) and 90 (33 to 100) respectively. The mean pre- and post-operative Lysholm scores were 50 (18 to 68) and 92 (28 to 100) respectively and the mean University of California Los Angeles activity scores were 8.5 before injury (4 to 10), 4.3 (3 to 6) after injury and 8.3 (4 to 10) post-operatively. There were three graft failures (8.6%) requiring revision. We conclude that reconstruction of the anterior cruciate ligament in carefully-selected patients aged 50 years or over can achieve similar results to those in younger patients, with no increased risk of complications.

Osteoarthritic changes after anterior cruciate ligament reconstruction using bone-patellar tendon-bone or hamstring tendon autografts: a retrospective, 7-year radiographic and clinical follow-up study

PURPOSE

This study was undertaken to evaluate the long-term radiographic appearance and clinical outcome after anterior cruciate ligament (ACL) reconstruction by use of either bone-patellar tendon-bone (BPTB) or hamstring tendon (HT) autografts and to evaluate how associated meniscal injuries affect the prevalence of osteoarthritis (OA).

METHODS

ACL reconstruction was performed in 124 consecutive patients. Of these patients, 113 (91%) (72 BPTB and 41 HT) returned for a follow-up examination at a median of 86 months (range, 67 to 111 months) after reconstruction. The patients underwent standard weight-bearing radiographic examinations and clinical evaluation.

RESULTS

The radiographic assessments showed no significant differences between the graft types in terms of OA classified according to the Ahlbäck and Fairbank rating systems. Overall, 23% of the patients had degenerative changes according to the Ahlbäck system, and 74% had degenerative changes according to the Fairbank system. Associated meniscal injuries increased the prevalence of OA. Clinically, no significant differences were found between the graft types in terms of the Tegner activity test, 1-leg hop test, International Knee Documentation Committee evaluation system, disturbed area of sensitivity, manual Lachman test, KT-1000 laxity test (MEDmetric, San Diego, CA), and knee-walking test. The Lysholm score (P = .02) and knee-walking ability (P = .02) were significantly better in the HT group.

CONCLUSIONS

At a median of 7 years after ACL reconstruction with either BPTB or HT autografts, the prevalence of OA as seen on standard weight-bearing radiographs and the clinical outcome were comparable. The presence of meniscal injuries increased the prevalence of OA.

LEVEL OF EVIDENCE

Level III, therapeutic, retrospective comparative study.

Anterior cruciate ligament reconstruction in patients who have excessive joint laxity

BACKGROUND

The purpose of the present study was to compare the clinical results of anterior cruciate ligament reconstruction with use of different grafts in patients with or without excessive joint laxity.

METHODS

We retrospectively studied eighty-three patients (forty-eight men and thirty-five women) who had undergone anterior cruciate ligament reconstruction between June 2002 and August 2004. Of the thirty-one patients who had generalized joint laxity, twenty were managed with an autologous bone-patellar tendon-bone graft and eleven were managed with a four-bundle hamstring (semitendinosus-gracilis tendon) graft. Of the fifty-two patients who had normal joint laxity, thirty-three were managed with a bone-patellar tendon-bone graft and nineteen were managed with a hamstring graft. Clinical results were evaluated by means of an examination at a minimum of twenty-four months after surgery.

RESULTS

Among the patients who had normal joint laxity, the mean side-to-side difference in anterior tibial translation on testing with the KT-2000 arthrometer at a minimum of twenty-four months postoperatively was 2.7 +/- 1.9 mm in the bone-patellar tendon-bone graft group and 3.5 +/- 1.7 mm in the hamstring graft group. This difference was not significant. The mean Lysholm score was 91 +/- 7 points in the bone-patellar tendon-bone graft group and 85 +/- 10 points in the hamstring graft group (p = 0.492). The side-to-side difference in anterior translation had an inverse correlation with the Lysholm score (beta = -0.604, p < 0.001). Among the patients who had excessive joint laxity, the mean side-to-side difference in anterior tibial translation was 3.4 +/- 1.5 mm in the bone-patellar tendon-bone graft group and 4.5 +/- 2.0 mm in the hamstring graft group (p = 0.036). The mean Lysholm score was 89 +/- 7 points in the bone-patellar tendon-bone group and 79 +/- 12 points in the hamstring group (p = 0.015). The side-to-side difference in anterior translation had an inverse correlation with the Lysholm score (beta = -0.708, p < 0.001).

CONCLUSIONS

In patients who have excessive joint laxity, the two-year outcomes of anterior cruciate ligament reconstruction with bone-patellar tendon-bone grafts are better than those with four-bundle hamstring grafts in terms of both side-to-side anterior laxity and clinical results.

[Meniscus and cartilaginous lesions. Influence of the delay between ACL injury and ligament reconstruction in 40-year-old patients]

PURPOSE OF THE STUDY

Anterior cruciate ligament (ACL) reconstruction is increasingly proposed for patients aged over 40 years. We report a retrospective analysis of a consecutive series of middle-aged patients who underwent ACL reconstruction surgery in order to analyze the development of meniscal and cartilage lesions and ascertain short-term outcome.

MATERIAL AND METHODS

Thirty-five patients aged over 40 years (mean 46.1 years) underwent hamstring ACL reconstruction, 19 for persistent instability after functional treatment and 16 after a recent tear in patients who wanted to resume their sports activities. Mean follow-up was 25 months. The IKDC 1993 score was noted as was the Arpege score for sports activity and Telos at 15 and 25kg.

RESULTS

At the last follow-up, the IKDC score was A or B in 85% of patients. Among the first intention ligamentoplasties, 94% were scored A or B at last follow-up and all had a single leg jump test greater than 76%. Among patients operated on after failure of functional treatment, 79% were scored A or B (p>0.05) and 32% had a single leg jump test less than 75% (p<0.05). Intraoperative discovery of meniscal or cartilage damage was statistically less significant in first intention patients than after failure of functional treatment. Somewhat less than half of the active and motivated patients aged over 40 years who underwent a first intention operation were unable to resume their sports activities at the same level. However, patients who underwent ACL repair after failure of functional treatment unexpectedly recovered sports activities after an interruption of several months or even years.

DISCUSSION

Age is not a barrier to ACL reconstruction. The time from injury to surgery is a prognostic factor predictive of meniscal and osteochondral damage. Early repair of the ACL preserves the knee's meniscal and cartilaginous stock. For active motivated patients aged over 40 years, who undergo a first-intention procedure, resumption of sports activities at the same level cannot be guaranteed after ACL. However, for patients who undergo surgery after failure of functional treatment, ACL reconstruction not only eliminates the troublesome laxity but also enables resumption of sports activities even after several months or years of interruption.

Complications of anterior cruciate ligament reconstruction with bone-patellar tendon-bone constructs: care and prevention

Rupture of the anterior cruciate ligament is a common injury. Correct diagnosis and patient selection, along with proper surgical technique, with careful attention to anatomic graft placement, followed by attention to proper rehabilitation, leads to predictably good to excellent results. This article reviews the recognition and avoidance of complications associated with bone-patellar tendon-bone constructs of anterior cruciate ligament reconstruction.