Matthias J. Feucht

The role of the tibial slope in sustaining and treating anterior cruciate ligament injuries

PurposeA steep tibial slope may contribute to anterior cruciate ligament (ACL)-injuries, a higher degree of instability in the case of ACL insufficiency, and recurrent instability after ACL reconstruction. A better understanding of the significance of the tibial slope could improve the development of ACL injury screening and prevention programmes, might serve as a basis for individually adapted rehabilitation programmes after ACL reconstruction and could clarify the role of slope-decreasing osteotomies in the treatment of ACL insufficiency. This article summarizes and discusses the current published literature on these topics.MethodsA comprehensive review of the MEDLINE database was carried out to identify relevant articles using multiple different keywords (e.g. ‘tibial slope’, ‘anterior cruciate ligament’, ‘osteotomy’, and ‘knee instability’). The reference lists of the reviewed articles were searched for additional relevant articles.ResultsIn cadaveric studies, an artificially increased tibial slope produced an anterior shift of the tibia relative to the femur. While mathematical models additionally demonstrated increased strain in the ACL, cadaveric studies have not confirmed these findings. There is some evidence that a steep tibial slope represents a risk factor for non-contact ACL injuries. MRI-based studies indicate that a steep slope of the lateral tibial plateau might specifically be responsible for this injury mechanism. The influence of the tibial slope on outcomes after ACL reconstruction and the role of slope-decreasing osteotomies in the treatment of ACL insufficiency remain unclear.ConclusionThe role of the tibial slope in sustaining and treating ACL injuries is not well understood. Characterizing the tibial plateau surface with a single slope measurement represents an insufficient approximation of its three-dimensionality, and the biomechanical impact of the tibial slope likely is more complex than previously appreciated.Level of evidenceIV.

Biomechanical Comparison Between Suture Anchor and Transtibial Pull-out Repair for Posterior Medial Meniscus Root Tears:

Background: Posterior medial meniscus root (PMMR) tears have a serious effect on knee joint biomechanics. Currently used techniques for refixation of the PMMR include the transtibial pull-out repair (TP) and suture anchor repair (SA). These techniques have not been compared biomechanically. Hypothesis: The SA technique provides superior biomechanical properties compared with the TP technique. Study Design: Controlled laboratory study. Methods: A total of 24 fresh-frozen porcine tibiae with attached intact medial menisci were used. The specimens were randomly assigned to 3 groups (8 specimens each). A standardized PMMR tear was created in 16 specimens. Refixation of the PMMR was performed by either the TP or SA technique. The native PMMR was left intact in 8 specimens. All specimens were subjected to cyclic loading followed by load-to-failure testing. Displacement after 100, 500, and 1000 cycles; maximum load to failure; stiffness; and displacement at failure were recorded. Results: Both repair techniques showed a significantly higher displacement during cyclic loading and a significantly lower maximum load and stiffness during load-to-failure testing compared with the native PMMR (P < .05). The SA technique showed a significantly lower displacement after 100, 500, and 1000 cycles (P < .001) and a significantly higher stiffness (P = .016) compared with the TP technique. Maximum load did not differ significantly between the SA and TP techniques (P = .027, Bonferroni adjustment). No significant difference between the 3 groups was observed for displacement at failure (P > .05). Conclusion: The SA technique provided superior biomechanical properties compared with the TP technique. Both repair techniques did not reach the strength of the native PMMR. Clinical Relevance: The favorable biomechanical properties of the SA technique might be beneficial for healing of the repaired PMMR and restoration of meniscus function. Because of inferior time zero stability compared with the native PMMR, slow rehabilitation is recommended after meniscus root repair.

Posterior root tear of the medial and lateral meniscus

An avulsion of the tibial insertion of the meniscus or a radial tear close to the meniscal insertion is defined as a root tear. In clinical practice, the incidence of these lesions is often underestimated. However, several biomechanical studies have shown that the effect of a root tear is comparable to a total meniscectomy. Clinical studies documented progredient arthritic changes following root tears, thereby supporting basic science studies. The clinical diagnosis is limited by unspecific symptoms. In addition to the diagnostic arthroscopy, MRI is considered to be the gold standard of diagnosis of a meniscal root tear. Three different direct MRI signs for the diagnosis of a meniscus root tear have been described: Radial linear defect in the axial plane, vertical linear defect (truncation sign) in the coronal plane, and the so-called ghost meniscus sign in the sagittal plane. Meniscal extrusion is also considered to be an indirect sign of a root tear, but is less common in lateral root tears. During arthroscopy, the function of the meniscus root must be assessed by probing. However, visualization of the meniscal insertions is challenging. Refixation of the meniscal root can be performed using a transtibial pull-out suture, suture anchors, or side-to-side repair. Several short-term studies reported good clinical results after medial or lateral root repair. Nevertheless, MRI and second-look arthroscopy revealed high rates of incomplete or absent healing, especially for medial root tears. To date, most studies are case series with short-term follow-up and level IV evidence. Outerbridge grade 3 or 4 chondral lesions and varus malalignment of >5° were found to predict an inferior clinical outcome after medial meniscus root repair. Further research is needed to evaluate long-term results and to define evident criteria for meniscal root repair.

Biomechanical Evaluation of Different Suture Techniques for Arthroscopic Transtibial Pull-out Repair of Posterior Medial Meniscus Root Tears

Background: A tear of the posterior medial meniscus root (PMMR) is increasingly recognized as a serious knee joint injury. Several suture techniques for arthroscopic transtibial pull-out repair have been described; however, only limited data about the biomechanical properties of these techniques are currently available. Hypothesis: There are significant differences between the tested suture techniques, with more complex suture configurations providing superior biomechanical properties. Study Design: Controlled laboratory study. Methods: A total of 40 porcine medial menisci were randomly assigned to 1 of 4 groups (10 specimens each) according to suture technique: two simple stitches (TSS), horizontal mattress suture (HMS), modified Mason-Allen suture (MMA), and two modified loop stitches (TLS). Meniscus-suture constructs were subjected to cyclic loading followed by load-to-failure testing in a servohydraulic material testing machine. Results: During cyclic loading, the HMS and TLS groups showed a significantly higher displacement after 100, 500, and 1000 cycles compared with the TSS and MMA groups. After 1000 cycles, the highest displacement was found for the TLS group, with significant differences compared with all other groups. During load-to-failure testing, the highest maximum load and yield load were observed for the MMA group, with statistically significant differences compared with the TSS and TLS groups. With regard to stiffness, the TSS and MMA groups showed significantly higher values compared with the HMS and TLS groups. Conclusion: The MMA technique provided the best biomechanical properties with regard to cyclic loading and load-to-failure testing. The TSS technique seems to be a valuable alternative. Both the HMS and TLS techniques have the disadvantage of lower stiffness and higher displacement during cyclic loading. Clinical Relevance: Using a MMA technique may improve healing rates and avoid progressive extrusion of the medial meniscus after transtibial pull-out repair of PMMR tears. The TSS technique may be used as an alternative that is easier to perform, but a more careful rehabilitation program is possibly necessary to avoid early failure.

Osteochondral Autologous Transfer Combined With Valgus High Tibial Osteotomy Long-Term Results and Survivorship Analysis

Background: Deep osteochondral defects of the medial femoral condyle in young and active patients are a serious condition that might lead to early osteoarthritis of the knee joint. Concomitant varus malalignment most likely promotes this process because of overloading of the medial compartment. Osteochondral autologous transfer (OAT) combined with valgus high tibial osteotomy (HTO) might therefore be a comprehensive solution to preserve long-term knee function in these patients. Purpose: To evaluate clinical long-term results and analyze survival rates (conversion to knee joint arthroplasty) after combined OAT and valgus HTO in young and active patients with symptomatic osteochondral defects of the medial femoral condyle and concomitant varus malalignment. Study Design: Case series; Level of evidence, 4. Methods: Between 1998 and 2008, combined OAT and valgus HTO was performed in 86 patients with deep osteochondral defects of the medial femoral condyle and concomitant varus malalignment >2°; 74 patients (86%) were available for follow-up evaluation. The mean age of patients was 38 years, and the mean follow-up time was 7.5 years. Knee function was assessed using the Lysholm score, and pain intensity was measured using the visual analog scale (VAS). The survival rates of this combined procedure were evaluated. Failure was defined as conversion to knee joint arthroplasty during the follow-up period. Results: Adjusted to follow-up time, the Lysholm score showed a mean increase of 33 points (95% CI, 27.1-39.4; P < .001) from 40 to 73, representing a significant improvement compared with preoperatively. The VAS score decreased by a mean of 4.8 points (95% CI, 4.1-5.5; P < .001) from 7.5 to 2.7, and 93% of the patients were satisfied with the results of the operative procedure. Mean survival rates were 95.2% ± 2.7% at 5 years, 93.2% ± 3.3% at 7 years, and 90.1% ± 4.4% at 8.5 years after surgery. Conclusion: Combined OAT and valgus HTO is an option to successfully treat patients with deep osteochondral defects of the medial femoral condyle and concomitant varus malalignment. Significantly improved knee function, decreased pain intensity, and a high survivorship rate can be expected up to 8.5 years postoperatively.

Avulsion of the anterior medial meniscus root: case report and surgical technique

AbstractInjuries of the meniscus roots have become increasingly recognised as a serious pathology of the knee joint. However, the current available literature focuses primarily on posterior meniscus root tears. In this article, a case with an isolated avulsion of the anterior medial meniscus root is presented, and a new arthroscopic technique to treat this type of injury is described. The anterior horn of the medial meniscus was sutured with a double-looped nonabsorbable suture and reattached to the tibial plateau using a knotless suture anchor. This technique may also be useful to treat avulsion injuries of the anterolateral or posteromedial meniscus root, and symptomatic subluxation of the medial meniscus in case of a variant insertion anatomy with an absent attachment of the anterior horn of the medial meniscus to the tibial plateau. Level of evidence V.

Biplanar supracondylar femoral derotation osteotomy for patellofemoral malalignment: the anterior closed-wedge technique

Patellofemoral malalignment can be caused by several factors including increased internal torsion of the femur. As a causative treatment method, supracondylar femoral derotation osteotomies have been proposed. For valgus- and varus-producing supracondylar femoral osteotomies, a biplanar osteotomy has been introduced in order to enhance primary fixation stability and osseous consolidation by increased bone-to-bone contact. In this article, a modification of this technique is described, which allows for a biplanar supracondylar femoral derotation osteotomy. Level of evidence V.

Patients’ expectations of shoulder instability repair

PurposeTo analyze and compare patient expectations of primary and revision shoulder stabilization and to assess the factors associated with patients’ expectations.MethodsPre-operative patient expectations after shoulder instability repair were prospectively assessed using a self-designed questionnaire. The survey included questions on the expected level and type of return to sports, instability, pain, risk of osteoarthritis, and overall shoulder condition.ResultsOne-hundred and forty-five patients (99 primary; 46 revision repair) were included. A return to sport at the same level with slight to no restrictions was expected in 95%, a return to high-risk activities in 34%, to moderate in 58%, and to low-risk activities in 9%. No pain [instability] independent of the activity level was expected by 71% [79%] and occasional pain [instability] during contact and overhead activities by 25% [19%]. 61% expected to have no risk of glenohumeral osteoarthritis, 37% a slight, and 2% a significant risk. The overall expectation for the post-operative shoulder was indicated to be normal or nearly normal in 99% of patients. The revision group did not differ from the primary repair group in any variable. High pre-operative sport performance was positively correlated with post-operative sport expectations. The number of dislocations, the duration of instability, and the subjective instability level were negatively correlated with return to sport expectations.ConclusionPatient expectations for primary and revision shoulder instability repair are high. Realistic patient expectations regarding the surgical procedure are necessary to avoid low patient satisfaction, especially in pre-operatively highly active and demanding athletes. The surgeon must not solely base the treatment on the pathology and possible risk factors for failure but should also take the individual expectation of the patient into account.Level of evidenceIII.

Intraoperative biologische Augmentation am Meniskus

ZusammenfassungHintergrundDie operative Therapie von Meniskusläsionen muss nicht nur die biomechanischen, sondern auch die spezifischen biologischen Gesetzmäßigkeiten der Meniskusheilung berücksichtigen. Trotz wesentlicher Fortschritte bei den Refixations- und Nahttechniken von Meniskusläsionen mit entsprechend biomechanisch ausgereiften, minimal-invasiven Systemen ist die Versagensrate bei meniskuserhaltenden Eingriffen relevant, was auf die limitierte Vaskularisierung der zentralen Meniskuszonen zurückzuführen ist.MethodenVerschiedene biologische Augmentationstechniken sind beschrieben, um das Heilungspotenzial bei operativ versorgten Meniskusläsionen zu verbessern. Ungerichtete intraoperative biologische Augmentationstechniken werden bereits seit Jahren im klinischen Alltag eingesetzt, allerdings mit bisher geringem Evidenzlevel. Diese umfassen das intraläsionale bzw. parasynoviale Raspeln, die Trepanation bzw. das Needling, die Mikrofrakturierung, die Verwendung von Fibrinclots und in den letzten Jahren auch die Anwendung von thrombozytenreichen Konzentraten. Diese Maßnahmen sollen biologische, den Heilungsprozess aktivierende Substanzen liefern.SchlussfolgerungNeuere biologische Augmentationsverfahren, wie der gezielte intraoperative Einsatz von Wachstumsfaktoren und/oder zellbasierter Therapien von mesenchymalen Stammzellen, rücken zunehmend in den wissenschaftlichen Fokus. Die Komplexität der Heilungsvorgänge an den Menisken müssen jedoch erst im Detail erforscht und verstanden werden, bevor ein erfolgreicher Transfer in das klinische Setting gelingt.AbstractBackgroundThe surgical treatment of meniscal lesions has to consider not only the biomechanical but also the specific biological principles of meniscus healing. Despite essential progress with respect to refixation and suture techniques for meniscal lesions, including biomechanically sophisticated minimally invasive systems, the failure rate of meniscus-preserving surgery is still clinically relevant. A limited vascularization of the central meniscal zones seems to be the most important factor.MethodsVarious biological augmentation techniques have been developed for enhancement of the healing ability following surgically treated meniscal lesions. Non-directive intraoperative biological augmentation techniques have already been established in the clinical setting for many years; however, the evidence level of these procedures is still low. Intralesional and parasynovial rasping, trephination, needling, microfracturing, use of fibrin clots and recently the application of platelet-rich concentrates are all included under these intraoperative biological augmentation techniques.ConclusionOverall, these interventions can provide biologically active substrates for improved healing. Novel biological augmentation procedures, e.g. specific intraoperative use of growth factors and/or cell-based therapies of mesenchymal stem cells, are under scientific investigation. However, the complexity of the healing processes in the menisci must be studied and understood in detail before a successful transfer into the clinical setting can be realized.

Rotator cuff Repair

Symptomatic partial or complete tear of the supraspinatus tendon associated with functional deficit and/or pain. Specific contraindications for repair include: tendon retraction medially > grade 3 (Patte), muscle atrophy > grade 3 (Thomazeau), fatty infiltration > grade 3 (Goutallier), concomitant advanced osteoarthritis of the shoulder and superior migration of the humeral head (rotator cuff arthropathy ) and upper brachial plexus lesions.