Rekonstruktion des vorderen Kreuzbandes

The treatment of ruptures of the anterior cruciate ligament (ACL) plays an essential role for both clinicians and resident physicians. To date many questions regarding the outcome as well as ACL reconstruction techniques have not yet been conclusively clarified. Whether reconstruction of the ACL protects the knee from osteoarthritis is still unproven; however, it is well known that an unstable knee joint is more vulnerable to secondary injuries, such as meniscal tears. Thus, early ACL reconstruction is recommended to minimize the risk of these secondary injuries. Three alternative sources of material for autologous ACL reconstruction are commonly utilized. An accessory hamstring (i.e. semitendinosus tendon with or without the gracilis tendon), a central strip of the patellar tendon with bone blocks and a central strip of the quadriceps tendon with or without bone block are the most common donor tissues used in autografts. Besides selection of the type of graft, the tendon diameter also plays a crucial role. Some progress has recently been made with respect to tunnel placement. The aim is to find an anatomical tunnel position. Reconstruction of both the anteromedial and the posterolateral ACL bundles helps to rebuild the anatomy of the original ACL; however, scientifically this approach did not lead to any improvement in the results. For fixation techniques a differentiation is made between aperture, extracortical and implant-free fixation. Generally, re-ruptures are less common than revisions as a result of graft ruptures due to technical mistakes during surgery. The most common mistakes concern tunnel placement and graft fixation. Also overlooked instability can have a negative influence on the outcome of ACL reconstruction.     

Rekonstruktion des vorderen Kreuzbandes bei Kindern

Zusammenfassung Operationsziel Rekonstruktion des vorderen Kreuzbandes bei Kindern ohne dauerhafte Schädigung der Wachstumsfugen an Tibia und Femur. Die distal gestielte Semitendinosussehne wird durch einen Bohrkanal in der medialen tibialen Epiphyse eingezogen, dann durch das Gelenk hinter den lateralen Femurkondylus geführt und an seiner Außenseite mit einer Krampe fixiert. Indikationen Symptomatische oder chronische Knieinstabilität als Folge einer vorderen Kreuzbandruptur. Eingeschränkte Kniegelenkfunktion. Erfolglose konservative Therapie. Kontraindikationen Fehlende Motivation zur Rehabilitation. Jugendliche mit abgeschlossenem Knochenwachstum. Operationstechnik Nach Absetzten der Sehne des Musculus semitendinosus an seinem muskulotendinösen Übergang etwa in der Mitte des dorsalen Oberschenkels wird diese mit Hilfe einer zweiten anteromedialen Inzision zunächst vor den Pes anserinus mobilisiert. Anschließend wird die Sehne unter dem Pes anserinus hindurch an die anteromediale Flä,che der proximalen Tibia gezogen. Von hier wird ein Bohrkanal durch die tibiale Epiphyse zum Ansatz des vorderen Kreuzbandes geschaffen. Die Sehne wird durch das Gelenk in "Over-the-top"-Technik hinter den lateralen Femurkondylus gebracht und dort an seiner Außenseite mit einer Krampe fixiert. Ergebnisse Zwischen 1990 und 1998 wurden drei Kinder (zwei Mädchen, ein Junge) operiert. Die Nachbeobachtungszeit betrug durchschnittlich 19 (14 bis 42) Monate. Während vor der Operation alle Kinder einen positiven Lachman-Test aufwiesen, war er postoperativ bei zwei Kindern negativ und bei einem Kind erstgradig positiv. Alle Kinder nahmen ihre ursprünglichen sportlichen Aktivitäten wieder auf und beklagten keine Instabilität oder Schmerzen. Bewegungsumfang und Kraftentwicklung der operierten Kniegelenke waren seitengleich. Summary Objectives Reconstruction of the anterior cruciate ligament in children without creating permanent damage to the tibial or femoral physes. The semitendinosus tendon, left attached distally, is passed through a tunnel in the tibial epiphysis, led through the joint, passed behind the lateral femoral condyle and fixed to the outer aspect of the femur with a staple. Indications Symptomatic or recurrent knee instability. Impaired function of the knee. Failure of conservative treatment. Skeletally immature child with bone age less than 12 years. Contraindications Lack of motivation for rehabilitation. Skeletally mature child. Surgical Technique After division of the semitendinosus tendon at ist musculotendinous junction, the tendon is pulled into a second incision over the pes anserinus. It is then passed under the pes anserinus to the anteromedial flare of the tibia where a tunnel is drilled through the tibial epiphysis into the joint, the tendon is passed through this tunnel, led around the posterior aspect of the lateral femoral condyle and fixed with a staple over the outer aspect of the lateral femoral condyle. Results Between 1990 and 1998, 3 children (2 girls, 1 boy, average age: 15 years, 4 months) underwent this reconstruction with the semitendinosus transfer. The follow-up period ranged from 14 to 42 months with an average 19 months. Whereas all children had a positive Lachman sign preoperatively, 2 had a negative Lachman sign and 1 a Grade-I Lachman at follow-up. All children returned to their former sport activities with no complaints of instability or pain. The range of motion and the strength of the operated knee were full.     

Arthroskopische Rekonstruktion des vorderen Kreuzbandes in Press-fit-Technik

Purpose

Problems related to the use of interference screws for fixation of bone-patellar tendon-bone grafts for anterior cruciate ligament (ACL) replacement have led to increasing interest in press-fit techniques. Most of the described techniques use press-fit fixation on either the femoral or tibial side. Therefore an arthroscopic technique was developed which achieves bone-patellar tendon-bone graft fixation by press-fit on both sides without the need for supplemental fixation material.

Methods

The first consecutive 40 patients were examined clinically with a KT-1000 arthrometer and radiologically after a mean of 28.7 months (range 20–40 months) postoperatively.

Results

The mean difference in side-to-side laxity was 1.3 mm (SD 2.2 mm) and the results according to the International Knee Documentation Committee (IKDC) score were as follows: 7 A, 28 B, 5 C, 0 D.

Conclusions

The presented press-fit technique avoids all complications related to the use of interference screws. It achieves primary stable fixation of the bone-patellar tendon-bone graft thereby allowing early functional rehabilitation. However, fixation strength depends on bone quality and the arthroscopic procedure is demanding. The results showed reliable stabilization of the operated knees.     

Fremdmaterialfreie Rekonstruktion des vorderen Kreuzbandes mit autologer Quadrizepssehne

Background

Reconstruction of the anterior cruciate ligament (ACL) is a widely used procedure, but up to now no results have been published on an implant-free technique using a quadriceps tendon autograft and press-fit fixation.

Methods

A total of 112 patients with primary rupture of the anterior cruciate ligament were included in a prospective case control study and 106 patients could be evaluated postoperatively after a mean of 12.4 months (range 12–14 months).

Results

The patients showed good to excellent results according to the Lysholm score in 81% and the International Knee Documentation Committee (IKDC) score in 86% of cases. Furthermore the anterior-posterior translation was less than 3 mm in 83% of the patients by testing with the KT-1000 arthrometer. Neither tunnel widening nor an increase of radiological joint degeneration was recorded by radiological examination.

Conclusion

Reconstruction of the ACL with an autologous quadriceps tendon and an implant-free technique yielded good results compared to established operative methods in the short-term and should be consistently followed-up for long-term confirmation.     

Tibiale Press-fit-Fixierungen von Beugesehnen zur Rekonstruktion des vorderen Kreuzbandes

Background

Press-fit fixation of hamstring tendon autografts for anterior cruciate ligament reconstruction is an interesting technique because no hardware is necessary. This study compares the biomechanical properties of press-fit fixations to an interference screw fixation.

Methods

Twenty-eight human cadaveric knees were used for hamstring tendon explantation. An additional bone block was harvested from the tibia. We used 28 porcine femora for graft fixation. Constructs were cyclically stretched and then loaded until failure. Maximum load to failure, stiffness and elongation during failure testing and cyclic loading were investigated.

Results

The maximum load to failure was 970±83?N for the press-fit tape fixation (T), 572±151?N for the bone bridge fixation (TS), 544±109?N for the interference screw fixation (I), 402±77?N for the press-fit suture fixation (S) and 290±74?N for the bone block fixation technique (F). The T fixation had a significantly better maximum load to failure compared to all other techniques (p<0.001).

Conclusion

This study demonstrates that a tibial press-fit technique which uses an additional bone block has better maximum load to failure results compared to a simple interference screw fixation.     

Die Zwei-Bündel-Technik – eine anatomische Rekonstruktion des vorderen Kreuzbandes

OBJECTIVE: To improve the rotational stability of the knee by anatomic reconstruction of the anterior cruciate ligament by socalled double-bundle technique using anteromedial and posterolateral grafts from native semitendinosus and gracilis. The grafts are fixed with bioabsorbable screws utilizing aperture fixation. INDICATIONS: Complete tear of the anterior cruciate ligament with positive Lachman sign and pivot shift. CONTRAINDICATIONS: Open growth plate. Osteoarthritis > grade 1 according to J?ger & Wirth. Age > or = 50 years with low sports activity (relative contraindication). SURGICAL TECHNIQUE: Graft harvest of the semitendinosus and gracilis tendons via a 3-cm horizontal skin incision parallel to pes anserinus and preparation of the tendons as double-looped grafts. Arthroscopy, resection of the stump of the anterior cruciate ligament, and clearance of its origin and insertion. Tunnel placement by means of aiming devices in the following order: tibial posterolateral, tibial anteromedial, femoral anteromedial (transtibial or via the anteromedial portal in 120 degrees flexion), and femoral posterolateral (via additional medial arthroscopic portal). The anteromedial (semitendinosus tendon) and posterolateral (gracilis tendon) bundles are passed through the tunnels and fixed on the femoral side. Tibial fixation of the graft by bioresorbable interference screw with knee flexion of 45 degrees (anteromedial) and 10 degrees (posterolateral). POSTOPERATIVE MANAGEMENT: Depending on the degree of swelling, rehabilitation with partial weight bearing for 14 days and full range of motion. Return to sports after 6 months, no contact sports until 9 months. RESULTS: From May 2004 to June 2005, anatomic double-bundle reconstruction was performed in 19 patients (13 male, six female, average age 31 years [18-48 years]) with isolated anterior cruciate ligament rupture without concomitant lesions. Clinical follow-up examination on average at 21.3 months (16-30 months) postoperatively. The Lysholm Score improved from an average of 65.2 to 94.5 points (75-100 points). The IKDC (International Knee Documentation Committee) Score yielded nine very good and ten good results in the relevant subgroups of motion, effusion and ligament stability. Measurement of anteroposterior translation with the KT-1000 instrument at 134 N showed increased translation of 1.8 mm (-2 to 5 mm) compared to the contralateral knee.     

Die Augmentationsnaht des vorderen Kreuzbandes

Zusammenfassung Hintergrund Die isolierte prim?re Naht des vorderen Kreuzbandes (VKB) erscheint aufgrund experimenteller und klinisch-wissenschaftlicher Ergebnisse fragwürdig. In einer tierexperimentellen Untersuchung wird die Augmentationsnaht des VKB mit einer Polydioxanon-Kordel (PDS^Ŗ) der isolierten VKB-Naht und der Augmentationsnaht mit der Patellarsehne gegenübergestellt. Methode 30 Schafe wurden 6 Versuchsgruppen zugeordnet: femorale (Gruppe 1, 3 bis 6) oder tibiale (Gruppe 2) Naht mit verschiedenen Nahtmaterialien sowie Augmentation dieser Naht mit einer PDS-Kordel (Gruppe 5) bzw. einem gestielten Patellarsehnenstreifen (Gruppe 6). Ergebnisse Für die femorale Naht mit Polyglactin 910 ergeben sich biomechanisch sinnlose Werte. Die tibiale Reinsertion zeigt demgegenüber nur geringfügig bessere Ergebnisse. Nur die Naht mit Polyesterf?den erreicht die geforderten 200 N, die femorale Naht mit Polydioxanon ist wenig schw?cher. Bei den Parametern Bruchkraft und Ri?arbeit sind beide Augmentati-onsverfahren jedweder Nahttechnik überlegen, bei der Steifigkeit sind die Unterschiede weniger deutlich. Die Compliance und der Compliance-Index sind am weitesten vom Normbereich eines normalen VKB entfernt. Schlu?folgerung 1. Für die isolierte Kreuzbandnaht gibt es keine tierexperimentelle Grundlage: Auch unter den theoretisch bestm?glichen Voraussetzungen ist eine VKB-Naht bei gleichzeitiger frühfunktioneller Nachbehandlung erfolglos. 2. Die tibiale Naht hat eine geringfügig bessere Prognose als die femorale Naht (ohne klinische Relevanz). 3. Der postoperative makroskopische Aspekt einer VKB-Rekonstruktion sagt wenig über die biomechanische Funktion aus. 4. Jede Augmentationsnaht ist der isolierten Naht überlegen. 5. Der. Patellarsehnenstreifen ist das bessere Augmentat, die gedoppelte PDS-Kordel bei konservativer Nachbehandlung eine gerechtfertigte Alternative.      

Verletzungen des vorderen Kreuzbandes bei Sportlern

Anterior cruciate ligament ruptures represent serious injuries for athletes which are often associated with accompanying injuries and lead to relevant kinematic alterations in the femorotibial roll-glide mechanism of the knee joint. Instability resulting in recurrent giving way events, as well as instability-related meniscal and cartilage lesions can cause functional long-term impairment that may limit the athlete’s career. Anterior cruciate ligament replacement is therefore considered to be the gold standard for recovery of physical performance and to prevent secondary meniscal and cartilage damage. Continuous changes in the reconstruction of the anterior cruciate ligament have led to a variety of different methods, including graft choice, fixation devices and surgical techniques, which support the consideration of individual requirements of the athlete as well as sport-specific aspects. One of the main factors for restoring stability and the physiological kinematic roll-glide mechanism of the knee is an anatomical tunnel placement as well as a stable graft fixation in the tibia and femur. By achieving of these fundamental technical requirements an early functional rehabilitation and accelerated recovery of neuromuscular skills, strength and coordination can be achieved, so that an early return to sport activities is possible.     

Ersatz des vorderen Kreuzbandes beim Kind

Trauma und Berufskrankheit - Die Inzidenz der kindlichen vorderen Kreuzbandruptur steigt aufgrund der zunehmenden Teilnahme an Risikosportarten auch in jüngeren Altersstufen an. Die...     

Lokale Infektionen nach Ersatz des vorderen Kreuzbandes

Two rare cases of local infections after reconstruction of the anterior cruciate ligament with Polydioxanon (PDS) cord and patellar/quadriceps tendon including patellar periosteum are presented.     

Verletzungen des vorderen Kreuzbandes und posturale Kontrolle

Background

Quantification of postural stability deficits after anterior cruciate ligament (ACL) rupture requires a complex measurement process, the so-called computerized dynamic posturography (CDP). It would be desirable if the decrease in postural stability caused by ACL rupture could be estimated by simpler functional scores. The aim of this study was therefore to review the currently available standard knee scores for the suitability to assess postural stability.

Patients and methods

In this study 58 patients with isolated unilateral ACL rupture were examined using CDP. The questionnaires used were Tegner, WOMAC, ADL-KOS, KOS-Sport, KSS and Lysholm scores. The values obtained were compared and correlated with the results of the CDP. In addition, a subgroup analysis of copers and non-copers was performed.

Results

There was no significant correlation with the postural stability deficit for any of the scores examined in this study. Only the subjectively perceived instability correlated appreciably with the CDP with r=0.423.

Conclusions

All currently used scores for the investigation of patients with ACL rupture cannot give any information about the ability of postural balance. If patients complain about an increased subjective feeling of instability a close observation of postural stability using CDP is inevitable.

     

Implantatfreier Ersatz des vorderen Kreuzbandes in Double-bundle-Technik

Reconstruction of the anterior cruciate ligament using the double bundle technique provides better covering of the anatomic insertion site areas and fiber length change behavior. Biomechanical studies and intraoperative measurements with computer navigation systems document increased stability in particular due to rotational stability. To date the impact of the posterolateral bundle is questioned and clinical studies have reported divergent outcomes. In favor of enhanced rotational stability, some techniques leave the basic principles of aperture or central graft fixation, decreasing primary stability and running the risk of tunnel widening especially on the femoral site. Additional use of interference screws means increased implants and costs and bone void in cases of revision is challenging. A technique for anatomic double-bundle reconstruction without the use of implants is presented, which allows for femoral aperture fixation with high primary stability of both bundles. In terms of the knot/press-fit technique of Paessler in the U-shaped tendons, a knot is created at the free end, which serves as a rigid press-fit anchoring in bottleneck shaped femoral drill holes at the insertion site of the anteromedial and posterolateral bundles. The drill holes are prepared in flexion of 110–115° using common offset and target drill devices. Mersilen tapes are applied to introduce the grafts from femoral to tibial and to fix the tendons over a bony bridge on the tibial site after preconditioning. The gracilis tendon mimics the posterolateral bundle and is fixed in 20° of flexion, the semi- tendinosus tendon is used for the anteromedial bundle and is fixed in 40° of flexion. The advantages of the presented technique are the central, rigid femoral anchoring without hardware, the thin bone tunnels which show no tunnel widening and allow for an optimal bone tendon contact to enhance bony ingrowth. The technique is cost-efficient and provides anatomic double bundle reconstruction of the anterior cruciate ligament. The sacrifice of hardware ensures easy revisions. The disadvantages are the peripheral tibial fixation, the preparation of the tendons needs tendon length and the creation of tendon knots providing high stability requires practice. The two femoral bone tunnels have proved to be safe regarding the stability of the lateral femoral condyle.     

Rekonstruktion des vorderen Kreuzbands mit dem CASPAR-System

After ACL reconstruction, there is a close correlation between follow-up results and tunnel positions, which indicates that the arthrometric tunnel placements are the most important factor. To improve positioning of the tunnels by preoperative planning and precise intraoperative execution, the CASPAR system was adapted for ACL surgery. To avoid incorporating pathologic hyperextension and rotation caused by the instability into the planning procedures, the stable controlateral knee joint is used as the physiological reference. The CT-based planning is carried out either with predefined templates or with free navigation. The tunnel drill holes are placed as defined by the arthrometric insertion points. The data are transferred to the unstable knee joint by an interactive matching procedure. The canals are drilled with a water-cooled diamond-plated milling cutterr while the knee joint is temporarily immobilized by means of a special condyle clamp. Then the ACL replacement is done according to the operative procedure generally followed in this hospital. From April 1999 to April 2000 94 patients were operated on according to the first treatment protocol. No major adverse effects related to the CASPAR system were noted. At the 2-year follow-up examination the patients showed no signs of graft impingement on MRI. Analysis of the patients with isolated ACL substitution revealed IKDC scores of A or B in 32 of these 36 patients. Our 24 months of clinical experience has shown this method to be safe, effective and accurate.     

Anatomische Ersatzplastik des vorderen Kreuzbandes mit der autologen Quadrizepssehne

Objective

Restore function of the anterior cruciate ligament (ACL).

Indications

Chronic functional instability with rupture of the ACL, giving way phenomena, acute rupture of the ACL with concomitant meniscus repair, rerupture of ACL graft with anatomical tunnels.

Contraindications

Local infection of the skin at the knee joint, local soft tissue damage, after rupture of the quadriceps tendon, enthesopathia of the quadriceps tendon, lack of patient compliance.

Surgical technique

Harvest quadriceps tendon graft with a bone block via a 4–5 cm long incision, starting from the middle third of the proximal patella pole without damaging the tendon fibers. Drill the femoral tunnel via a deep anteromedial portal with the knee flexed of more than 110° (tunnel diameter 0.5–1 mm smaller in diameter than bone block). Gentle tunnel preparation using dilators. In absence of an ACL stump the lateral meniscus anterior horn serves as tibial landmark. In case of revision surgery, remove graft material and implants from the tunnel. Graft fixation using press fit method in the femoral tunnel. Tibial graft fixation archieved with a resorbable interference screw and a button.

Postoperative management

Goal of the inflammatory phase (weeks 1–2) is pain and inflammation control (20 kg partial weight bearing). During the proliferative phase (weeks 2–6), load and mobility slowly increased (closed-chain exercises). During the remodeling phase (>?6 weeks), strength and coordination exercises are performed. In revision cases and in case of concomitant injuries, longer partial weight-bearing period might be necessary. Athletes should not return to competitive sports before 6–8 months.

Results

In a prospective study, 33 patients (age 16–48 years) were examined after replacement of the ACL with a quadriceps tendon graft after a minimum follow-up (FU) of 2 years (12 revision; 21 primary surgery). No post- or perioperative complications. Postoperative radiographs showed an anatomical tunnel location and no dislocation of the bone block. After 2 years the difference of a-p translation compared to the other leg was assessed by the use of KT 1000. The revision group improved from an average of 7.2 mm (pre-op) to 2.2 mm (FU). The group with primary surgery improved from 6.4 mm (pre-op) to 1.7 mm (FU). A sliding pivot shift phenomenon was detected in 2 patients in the revision group and 1 patient in the primary surgery group.     

Arthroskopische Arthrolyse bei Arthrofibrose nach Ersatzplastik des vorderen Kreuzbandes

Objective

Restoration of free knee motion taking into account knee extension, knee flexion, and patella mobility.

Indications

Prolonged knee motion restriction after anterior cruciate ligament (ACL) reconstruction, persistent decreased patella mobility, or extension deficit.

Contraindications

Existing significant joint irritation or active reflex dystrophy with persistent distinctive pain syndrome.

Surgical technique

Arthroscopic arthrolysis possible in most cases. Removal of adhesions in all compartments. Elimination of intraarticular cause of patella infera by removing infrapatellar scar tissue and fibrotic fat pad. In case of severe peripatellar fibrotic tissue, lateral release is useful with partial transection of lateral retinacula. In case of strong capsular contracture, additional medial release indicated to improve patella mobility. Important goal of arthrolysis: full range of knee extension. Arthrolysis for scar tissue removal in the posterior recessus through dorsomedial arthroscopic approach possible. In severe cases posteromedial arthrotomy for posterior capsule release required. Cyclops syndrome makes removal of all tissue adherent to the ACL necessary. An irregular ACL insertion or intercondylar notch stenosis may require notchplasty. Postoperative recurrence of fibrosis may require repeated arthroscopic surgery to improve mobility, such as notchplasty, osteophytes resection, scar removal, and releases.

Postoperative management

Immediate postoperative pain-free physical therapy taking into account full range of extension and patella mobility. Passive exercises under traction. Lymphatic drainage. No exercising in pain throughout the entire postoperative physical therapy. Continuous passive motion treatment for 4 weeks postoperatively useful. No muscle strength or equipment training for at least 3 months postoperatively.

Results

Based on the observations in our working group, approximately pproximately 78?% of patients develop knee osteoarthritis within 5 years.     

Stadiengerechte Therapie bei Infekten nach Ersatzplastik des vorderen Kreuzbandes

Objective

Debridement and irrigation of the knee joint and the donor site to reduce the amount of bacteria and to remove bacterial enzymes and inflammatory cytokines in cases with infection after replacement of the anterior cruciate ligament (ACL).

Indications

Proven infection, suspected infection.

Contraindications

High anesthesiological risk.

Surgical technique

The therapy of infections after ACL reconstruction depends on the different stages as described by Gächter. In stage I and II, arthroscopic debridement and irrigation (about 10 l) of all compartments is performed. Several biopsies for microbiological analysis are obtained during surgery. Broad-spectrum antibiotic therapy started immediately after surgery. Once the resistance of the bacteria is known, antibiotic therapy may be changed according to the results. When pain, swelling, elevated CRP, or white blood cells persists, arthroscopic irrigation is repeated. In stage III, a complete arthroscopic synovectomy is performed. When the graft is intact, it is left in situ. Resection is performed in case of graft insufficiency, tunnel malplacement, or persistent infection. When the bone tunnels are affected, they should be debrided. In stage IV with osteolysis, an arthrotomy with open debridement may be required. The surgical therapy can be supported with the application of local antibiotics.

Rehabilitation

Redon drainage is left in situ until the next irrigation is performed, control of wound and laboratory results, passive exercises, physiotherapy, systemic antibiotic therapy.

Results

Between 2008 and 2013, we treated 13 patients with an infection after replacement of the ACL. In all cases, complete healing was achieved. In 4 cases, the graft was resected. In 2 patients, arthrofibrosis developed and arthrolysis was required.