[Reconstruction of anterior cruciate ligament using bone-patellar tendon-borne graft or fascia lata graft. A retrospective study of functional results]

INTRODUCTION

The purpose of this study was to compare the functional results using two different types of reconstruction of the anterior cruciate ligament.

MATERIAL AND METHODS

A retrospective comparison of 34 patients operated with a fascia lata graft and 26 patients operated with a bone-patellar tendon-bone graft. The patients were evaluated twice with a postoperative Lysholm score, a preoperative and postoperative Tegner score, and a postoperative knee-laxity test.

RESULTS

The Lysholm scores after the first (P = 0.07) and second (P = 0.29) postoperative control showed no difference between the two groups. There was no difference between the preoperative and postoperative Tegner scores of the two groups (P = 0.42). A total of 27 patients out of 60 practiced sports or had knee-straining work postoperatively at the same level as preoperatively. No difference was found between the two groups when comparing the knee-laxity tests (P = 0.12).

DISCUSSION

This study did not find any difference in the final functional results when comparing the two operation techniques. Almost half of the patients can expect a return to sports at a preinjury level.

Decreased range of motion following acute versus chronic anterior cruciate ligament reconstruction

Eighty patients with acute anterior cruciate ligament (ACL) reconstruction were compared to 80 patients with chronic ACL reconstruction. Before reconstruction, all patients had 0 degrees-120 degrees active motion, performed a straight leg raise without loss of extension, and demonstrated good quadriceps control. At 3 months, 4 acute patients had decreased range of motion (<10 degrees-120 degrees), but none at 6 or 12 months, and did not require repeat surgery. One chronic patient had decreased range of motion at 3 and 6 months and 1 patient had decreased range of motion at 1 year; both patients required operative intervention. Using these specific preoperative criteria, no increased incidence of decreased range of motion was found when an ACL reconstruction was performed within 3 weeks of injury.

Monopolar thermal treatment of symptomatic anterior cruciate ligament instability

Patients with anterior cruciate ligament instability resulting from incomplete tears or elongation in continuity without ligament detachment historically have been treated conservatively or by graft replacement. The literature is sparse regarding alternative treatments. The current study presents experience using monopolar thermal repair on 28 consecutive knees with partial anterior cruciate ligament tears all symptomatically unstable. All lesions were less than 6 months old (average, 77 days; range, 7-180 days) and with a difference of 6 mm or more (average, 9 mm; range, 6-13 mm) when comparing both knees using KT-1000 evaluation. Incomplete tears of the anterior cruciate ligament were seen at arthroscopic evaluation. The rehabilitation protocol included use of a brace for at least 6 weeks and progressive weightbearing. A 2-year minimum followup (range, 24-35 months) was done in all patients following the International Knee Documentation Committee guidelines. The overall outcome was normal or nearly normal in 96% of the patients. One failure occurred at 8 weeks. Twenty-six knees had a KT-1000 difference between 0 and 2 mm (average, 1.9 mm). Because thermal application causes death to some of the cells directly treated, it should be taken into account in selection and application. Immediately after thermal use, the anterior cruciate ligament, although thicker and tighter, is at first weaker than normal. Rehabilitation and compliance are critical during early ligament healing. This procedure seems to be a reasonable alternative to anterior cruciate ligament grafting in selected patients.

Anterior cruciate ligament injury in children: update of current treatment options

As our society's interest in competitive athletics has grown, so has the participation of our youth. Unfortunately, along with this increase in participation has come a predictable increase in rate of injury. More specifically, anterior cruciate ligament injury in the skeletally immature individual is being recognized with increasing frequency and currently poses an unsolved clinical problem. Conservative management of midsubstance anterior cruciate ligament tears in the skeletally immature population has been shown to have an unfavorable prognosis related to functional knee instability, subsequent meniscal tears, and the development of early degenerative arthritis. Despite poor outcomes following conservative treatment, many orthopaedic surgeons have been reluctant to perform anterior cruciate ligament reconstructions in skeletally immature patients due to the potential for physeal injury and resultant growth disturbance. Although there is growing evidence in the literature suggesting that anterior cruciate ligament reconstruction in the adolescent population may be safely performed using anatomic, transphyseal techniques, there are insufficient data to provide concrete guidelines in treatment of anterior cruciate ligament injuries in the prepubescent population. Management of these injuries, therefore, must be based on the physiologic and skeletal maturity of the child. Anterior cruciate ligament reconstruction in the skeletally immature individual still poses a clinical problem with the safest and most effective techniques still evolving.

Radiofrequency treatment weakens the fatigue characteristics of rabbit anterior cruciate ligament

OBJECTIVE

To evaluate the radiofrequency treatment applied to an intact anterior cruciate ligament, and to quantify the mechanical effects of controlled cyclic loading (simulating activities of daily living) post-treatment.

DESIGN

An in vitro radiofrequency energy application to the rabbit anterior cruciate ligament and cyclic loading of the treated ligament.

BACKGROUND

Effect of cyclic loading on the radiofrequency treated ligament in a controlled environment is not known.

METHODS

In the treatment group radiofrequency treatment was applied to an intact ligament and then the ligament was cyclically loaded for 3000 cycles, and stretched-to-failure. Control group was similar to treatment, except that the radiofrequency treatment was not applied. The cyclic loading (approximately 6% tensile strain) was kept below the injury threshold of the rabbit anterior cruciate ligament and was designed to simulate loading post-treatment. A relaxation test (5% constant strain for 180 s) was used to compare the results at different steps in the experiment; within each group and between the two groups.

RESULTS

Relaxation force increased in the treatment group (average 108% of intact, P<0.05), but decreased after the cyclic loading (average 71% of intact, P<0.05). There were significant differences in the force-deformation-failure curves between the treatment and control groups: average treated ligament failed at 59% and 57% of the control values respectively for the deformation and force (P<0.05).

CONCLUSIONS

Using radiofrequency treatment makes rabbit anterior cruciate ligament weaker following cyclic loading.

RELEVANCE

The radiofrequency treatment weakens the anterior cruciate ligament, and therefore, it perhaps should be protected until healing and adaptation restore its full strength.

Low-load resistance muscular training with moderate restriction of blood flow after anterior cruciate ligament reconstruction

We performed a prospective study to determine the effects of introducing low-load muscular training with moderate restriction of blood flow during the first 16 weeks after reconstruction of the anterior cruciate ligament. 44 subjects (average age 29 (18-52) years) were randomized into a group that trained restriction of blood flow (group R, n = 22) and a group that trained without restriction (group N, n = 22). Both groups followed the same training schedule. Evaluations of knee extensor and flexor torques before surgery and 16 weeks after it showed a significant increase in muscular strength in group R as compared to group N. The preoperative/16-week postoperative ratio of the cross-sectional area of the knee extensor muscles showed a statistically significant enlargement in group R as compared to group N. 16 weeks after surgery, the short diameters of type 1 and type 2 fibers of M. vastus lateralis tended to be larger in group R (n = 8) than in group N (n = 8), although the differences were not significant. These findings show that low-load resistance muscular training during moderate restriction of blood flow is an effective exercise for early muscular training after reconstruction of the anterior cruciate ligament.

A review of ski injuries resulting in combined injury to the anterior cruciate ligament and medial collateral ligaments

Alpine skiing is a global winter recreational sport with 15 million participants in the United States alone, and an overall injury rate of 2.5 per 1,000 ski person-days. Isolated injury to the anterior cruciate ligament (ACL) or the medial collateral ligament (MCL) is common among ski injuries; however, combined injury to these structures is rare. Controversy in the management of ACL instability following alpine ski injury is diminishing with improvements in the techniques of intra-articular cruciate reconstruction. However, the management of the combined ACL-MCL injury remains something of an enigma. Evidence exists to support both surgical and nonsurgical management strategies for the medial structures, but little consensus exists for the timing of the repair. This paper highlights the mechanisms of ski injuries that can result in combined injury to the ACL and MCL. The anatomy and biomechanics of the medial complex as it relates both to stability and operative repair are reviewed, and literature on the techniques and indications used for MCL repair in the setting of a combined injury is presented. On the basis of this review, we believe that an injury to the MCL does not need to be repaired if the ACL is reconstructed after a combined injury.

Optimal entry point for retrograde femoral nailing

OBJECTIVE

The purpose of this study is to identify the optimum entry point for retrograde femoral nailing, defined as that point which will provide adequate fracture alignment while minimizing soft-tissue and articular cartilage injury.

DESIGN

Cadaveric study.

SETTING

Biomechanics laboratory.

MAIN OUTCOME MEASURE

Anatomic relationships and fracture reduction. METHODS Eleven cadaveric femori with attached knee joints underwent retrograde femoral nailing with a Synthes femoral nail (Synthes, Paoli, PA, U.S.A.). After placement of the nail, the specimens underwent an osteotomy 3 inches proximal to the articular surface. Multiple entry points were tested to determine fracture alignment and extent of articular cartilage injury. Medial-lateral and anterior-posterior displacements, in addition to any soft-tissue or articular surface trauma, were recorded for these various points of entry.

RESULTS

An entry point of 1.2 cm anterior to the femoral origin of the posterior cruciate ligament resulted in the least anterior-posterior displacement of the femoral shaft following fracture. In the coronal plane, an entry point at the midpoint of the intercondylar sulcus was identified as minimizing the displacement following fracture. This ideal position allows for proper seating of the nail within the intercondylar sulcus, resulting in minimal damage to the articular cartilage and posterior cruciate ligament and minimal disruption of the patella femoral joint.

CONCLUSION

Retrograde femoral nailing should be used cautiously in select patients, when conventional antegrade nailing cannot be used, due to the unavoidable injury to the knee articular surface associated with this technique. The optimum entry point of 1.2 cm anterior to the femoral posterior cruciate ligament origin and centered in the intercondylar sulcus provides the optimal balance of fracture reduction and knee joint sparing. It may be difficult to target this site with a percutaneous technique and may require direct visualization of the intercondylar sulcus for ideal nail placement.

[Performance of an open low-field MR unit in routine examination of knee lesions and comparison with high field systems]

The purpose of this study was to analyze the diagnostic value of a low-field open MR system in the diagnosis of knee lesions and to compare it with that of high-field MR systems. In 139 knees,arthroscopic investigations were used as the gold standard to calculate sensitivity, specificity, predictive values and accuracy of the low-field open MR system. Figures for high field systems were taken from the literature. The values for the open MR system relative to arthroscopy were as follows: sensitivity 66%,specificity 95%,positive predictive value 64%,negative predictive value 92%, and accuracy 82%. The corresponding values taken from 10 relevant publications for highfield systems were: sensitivity 81%, specificity 90%, accuracy 90%. A lower diagnostic performance has to be expected using open low field MR units for knee lesions in comparison to high field units. Sedative drugs can make it possible for claustrophobic patients to be investigated in high-field units. The use of open low-field scanners may still be indicated in very adipose patients who do not fit into closed units.

Postoperative analgesia in dogs receiving epidural morphine plus medetomidine

This investigation was carried out to compare the postoperative analgesia and plasma morphine concentrations in dogs given epidural morphine or epidural morphine combined with medetomidine prior to surgery. Twelve dogs (seven males and five females) with ruptured cranial cruciate ligaments presented to the Washington State University Veterinary Teaching Hospital. Six dogs received an epidural injection of morphine (0.1 mg/kg) and six dogs received epidural morphine (0.1 mg/kg) combined with medetomidine (0.005 mg/kg). Numeric rating scale (NRS) pain scores and cumulative pain scores (CPS) were assigned to 10-min segments of video. Video segments, heart rates and respiratory rates were recorded prior to premedication and at 4, 8, 12, 18 and 24 h after epidural injection. Blood was sampled from the cephalic vein at each of these times and during anesthesia at 0.5, 1, 2 and 3 h after epidural injection. Data were analyzed using either Friedman's test or one-way anova for repeated measures. In the morphine group, significant increases compared with premedication values were detected at 4, 8 and 12 h after epidural injection for NRS and at 4 and 12 h after epidural injection for CPS. In the morphine plus medetomidine group, NRS was significantly higher at 4 and 8 h whereas there were no differences from baseline values for CPS. Plasma morphine concentrations were not significantly different between treatment groups, but were significantly increased compared with preinjection values at 0.5, 1, 12, 18, and 24 h in the morphine plus medetomidine group. Epidurally administered morphine combined with medetomidine was associated with only minor benefits based on subjective pain scoring when compared with morphine alone in these dogs undergoing repair of a ruptured cranial cruciate ligament.

Femoral aimer deformation: Potential cause for altered femoral tunnel placement in anterior cruciate ligament surgery

In this case observational study, a standard commercially available femoral aimer used for endoscopic anterior cruciate ligament (ACL) reconstruction was found to have an abnormal bend in the offset tongue that is normally placed in the over-the-top position for ACL femoral aiming using an endoscopic technique. A standard 3/32-inch Steinmannn pin was placed through the aimer, and the offset distance measured 13 mm instead of the normal 7 mm. If this device had been used, significant error would have occurred, placing the anterior tunnel much more anterior than intended, thus potentially contributing to a surgical failure. The purpose of this case study is to alert physicians to check their femoral aimers to make certain that the offset tongue is parallel, thus assuring accurate placement of the provisional pin.

Gait perturbation response in chronic anterior cruciate ligament deficiency and repair

OBJECTIVE

To determine how chronic anterior cruciate ligament deficient and surgically repaired subjects react to unexpected forward perturbations during gait as compared to healthy controls.

DESIGN

Gait testing of 10 chronic anterior cruciate ligament deficient subjects prior to and three months following reconstructive surgery, and 10 uninjured controls.

BACKGROUND

The ability of an anterior cruciate ligament injured individual to react and maintain equilibrium during gait perturbations is critical for the prevention of reinjury. No studies have investigated how these individuals respond to unexpected perturbations during normal gait.

METHODS

An unexpected forward perturbation was induced upon heel strike using a force plate capable of translational movement.

RESULTS

Prior to surgery, the anterior cruciate ligament subjects exhibited a greater knee extensor moment in response to the perturbation compared to healthy controls. Following surgery, the anterior cruciate ligament injured subjects exhibited a static knee position and a sustained knee extensor moment throughout stance in response to the perturbation as compared to controls.

CONCLUSIONS

These data suggest that chronic anterior cruciate ligament deficient subjects rely heavily on knee extensor musculature to prevent collapse in response to an unexpected perturbation. This same reactive response was more pronounced 3 months following surgery.

RELEVANCE

The results suggest that, prior to and following surgery, chronic anterior cruciate ligament injured subjects respond differently than healthy controls to an unexpected perturbation during gait. Anterior cruciate ligament injured or repaired subjects do not reduce or avoid vigorous contraction of the quadriceps muscles when responding to gait perturbations.

Pretibial cyst formation after arthroscopic anterior cruciate ligament reconstruction

Pretibial cyst formation is a rare occurrence after anterior cruciate ligament (ACL) reconstruction. We report this complication after ACL reconstruction using a hamstring autograft. Bone grafting of the original tibial tunnels during revision surgeries after failed ACL reconstruction could prevent this rare complication.

Six degrees-of-freedom kinematics of ACL deficient knees during locomotion-compensatory mechanism

The purpose of the study was to investigate six degrees-of-freedom (DOF) kinematic changes in anterior cruciate ligament ACL-deficient knees during locomotion and the possible compensatory mechanism involved. Compared with healthy subjects, ACL-deficient patients walked with increased tibial external rotation throughout most of the stride and increased tibial abduction at the heel contact, and the tibia was more anterior during swing phase (P<0.05). Considering tibial external rotation and abduction unload the ACL, the kinematic changes indicated compensatory mechanism developed by patients to avoid unstable knee positions due to the loss of the ACL or to avoid stretching a partially torn ACL.

Messenger ribonucleic acid levels in disrupted human anterior cruciate ligaments

Thirty patients had anterior cruciate ligament reconstruction for ongoing instability. Two groups were defined according to gross morphologic features identified during reconstruction: anterior cruciate ligament disruptions with scars attached to a structure in the joint and disruptions without reattachments. Reverse transcription polymerase chain reaction for a subset of extracellular matrix molecules, proteinases, and proteinase inhibitors was done on samples of scarred anterior cruciate ligament tissue removed during reconstructive surgery. Results of the nonattached scar group showed significantly increased mRNA levels for Type I collagen, and an increased Type I to Type III collagen ratio compared with that for the attached scar group. In the first year after injury, decorin mRNA levels in the nonattached scar group also were significantly higher than in the attached scar group. Biglycan mRNA levels in the nonattached scar group correlated closely with Type I collagen mRNA levels. These results suggest differences in cellular expression in torn anterior cruciate ligaments that attach to structures in the joint versus those which do not. Although the molecular mechanisms responsible for these differences have not been delineated, different molecular signals may influence the gross morphologic features of anterior cruciate ligament disruptions or alternatively, differing gross morphologic features may be subject to different mechanical loads leading to altered molecular expression. However, the finding of endogenous cellular activity in injured anterior cruciate ligaments raises the possibility that this activity may be enhanced to improve outcomes.

[Results on treatment of anterior cruciate ligament rupture of immature and adolescents]

Between 01.01.1994 and 31.12.2000 we have operated 45 patients in our clinic with open growth plates. Cruciate ligament injuries are seldom found by children with open growth plates.Nevertheless, if the injury is left untreated it is liable to injure the meniscoid and the cartilage severely and may even lead to a loosening of the tertiary stabilizers. Therefore we do refixation of anterior cruciate ligament for tibial bony rupture and Refixation in Marschall technique or a replacement for the anterior cruciate ligament using Hamstring ligaments and fixated them by using the transfix technique.Up till now, none of the patients showed any signs of ill-functioning growth plates. Though it may be necessary to point out that the patients had not fully grown out by the time the subsequent check ups were held. The knees we revised were all stable and after relating our results to the IKDC-Score we found that our treatment reflected a good to very good result (Group A and B). Results of Marschall-Technique are very poor, results after bony refixations are good, result of our prospective study encourage us to recommend the surrogate of the anterior cruciate ligament by using the transfix technique in cases where the growth plates are still open. Therefore we can recommend reconstruction on transfix technique and refixation of bony ruptures.

A clinically applicable EMG-force model to quantify active stabilization of the knee after a lesion of the anterior cruciate ligament

OBJECTIVES

To investigate whether a simple electromyography-force (EMG-force) model can be used to measure different levels of co-contraction about the knee for healthy subjects and patients with an anterior cruciate ligament deficiency.

DESIGN

To evaluate an EMG-to-force processing model, two groups of subjects, with and without deficiency of the anterior cruciate ligament, participated in experiments in which surface EMG, kinematics and kinetics about the knee were recorded during isokinetic and functional movements.

BACKGROUND

Clinical and biomechanical evidence supports the hypothesis that higher level of co-contraction of quadriceps and hamstrings provide an active stabilization of the knee to compensate for the lost anterior cruciate ligament. To quantify the level of co-contraction, the contribution of both agonist and antagonist muscles to the net joint moment must be known.

METHODS

Surface EMG levels were calibrated to moment by means of a limited number of isokinetic contractions about the knee. With these calibration values, an estimate of the muscle moments during a vertical jump were obtained and compared with the net joint moment, calculated with inverse dynamics. Also co-contraction indices were determined.

RESULTS

The EMG-force model provided a fair estimate of the net joint moment. The co-contraction index in anterior cruciate ligament deficient subjects was significantly higher (mean 0.54 (SD, 0.04)) compared to healthy subjects (mean 0.25 (SD, 0.07)).

CONCLUSIONS

Although the EMG-to-force processing model is not perfectly accurate, it is appropriate within a clinical context.

RELEVANCE

Previous research supports the hypothesis that subjects with an anterior cruciate ligament deficiency compensate the loss of passive stability by developing higher co-activation levels of the knee muscles, i.e. active stabilization. Quantifying co-contraction may serve as a valuable parameter to evaluate clinical interventions and rehabilitation processes. The EMG-force model presented in this study appears to be a useful instrument for this purpose.

The ACL-deficient knee: natural history and treatment options

Injury to the anterior cruciate ligament removes the major stabilizing structure to anterior tibial translation. The initial trauma may lead to meniscal and cartilage damage, predisposing the knee to early degenerative changes. Moreover, a knee with an isolated ACL rupture may have recurrent episodes of instability that can lead to a similar degenerative course. At this time, one cannot accurately predict which patients will tolerate ACL deficiency, and which patients will not. Current long-term studies support a progressive worsening condition in the ACL and meniscal deficient knees. Physical therapy together with lifestyle modifications may be necessary. Those unwilling to make these types of changes or those with associated injuries may benefit from ACL reconstruction.

Surgical and postoperative complications associated with tibial plateau leveling osteotomy in dogs with cranial cruciate ligament rupture: 397 cases (1998-2001)

OBJECTIVE

To identify surgical and postoperative complications of tibial plateau leveling osteotomy (TPLO) in dogs with rupture of the cranial cruciate ligament (CCL) and compare their incidence with those reported in the literature for other commonly performed CCL stabilization procedures.

DESIGN

Retrospective study.

ANIMALS

346 dogs undergoing 397 TPLO procedures.

PROCEDURE

Medical records of dogs undergoing 563 consecutive TPLO procedures were reviewed. Complications were recorded and assigned to groups on the basis of the period during which the complication was observed.

RESULTS

397 TPLOs met the criteria for inclusion in the study. Complications (n = 136) were recorded in 113 of the 397 (28%) procedures. Multiple complications developed in 10 dogs. In 19 dogs, a second surgery was performed to manage complications. Development of a complication after surgery was not associated with age or body weight of the dog, tibial plateau angle prior to stifle joint surgery, or experience of the surgeon. Factors significantly associated with complications were breed and performance of an arthrotomy concomitantly with TPLO.

CONCLUSIONS AND CLINICAL RELEVANCE

TPLO was associated with development of numerous complications, some of which required surgical correction. Most complications resolved with nonsurgical treatment. Several complications were unique to the TPLO procedure because of the surgical technique and implants required. Although TPLO was associated with a greater number of complications than other CCL stabilization methods, the incidence of major complications was similar.

ACL reconstruction with hamstring tendon

The technique of quadrupled semitendinosus autograft for ACL reconstruction using the EndoButton for femoral fixation has been described. Dr. Rosenberg, this article's senior author, has used this for over 10 years with no known instance of fixation failure at the femur or tibia. This technique using QST reconstruction has little morbidity, low reoperation rate, and excellent clinical results.