Empfehlungen der AG Klinische Geweberegeneration zur Behandlung von Knorpelschäden am Kniegelenk

The Working Group of the German Orthopedic and Trauma Society (DGOU) on Tissue Regeneration has published recommendations on the indication of different surgical approaches for treatment of full-thickness cartilage defects in the knee joint in 2004, 2013 and 2016. Based upon new scientific knowledge and new developments, this recommendation is an update based upon the best clinical evidence available. In addition to prospective randomised controlled clinical trials, this also includes studies with a lower level of evidence. In the absence of evidence, the decision is based on a consensus process within the members of the working group.The principle of making decision dependent on defect size has not been changed in the new recommendation either. The indication for arthroscopic microfracturing has been reduced up to a defect size of 2 cm² maximum, while autologous chondrocyte implantation is the method of choice for larger cartilage defects. Additionally, matrix-augmented bone marrow stimulation (mBMS) has been included in the recommendation for defects ranging from 1 to 4.5 cm². For the treatment of smaller osteochondral defects, in addition to osteochondral transplantation (OCT), mBMS is also recommended. For larger defects, matrix-augmented autologous chondrocyte implantation (mACI/mACT) in combination with augmentation of the subchondral bone is recommended.

Impact of compression stockings on leg swelling after arthroscopy - a prospective randomised pilot study

Background

Post-operative limb swelling may negatively affect the outcome of arthroscopic surgery and prolong rehabilitation. The aim of this pilot study was to evaluate the effect of compression stockings versus no compression on post-operative swelling and pain in the early post-operative phase.

Methods

A single-centre, randomised controlled trial was performed. Patients who underwent minor knee arthroscopy were randomised to wear class II compression stockings (23-32 mmHg) (CS) or no compression stockings (NCS) immediately post-operatively for ten days. All patients received low molecular weight heparin (LMWH) at prophylactic dosage. The primary outcome variable was post-operative swelling of the limb, quantified by using an optical 3D measurement system (Bodytronic© 600). Pain was rated on a visual analogue scale (VAS). From a total of 76 patients assessed, 19 patients were eligible for final analysis. The trial followed the CONSORT criteria, was registered at clinicaltrial.gov and approved by the local ethics committee.

Results

The circumference at the middle thigh (cF) was significantly different between groups at day 10 (p = 0.032; circumference − 1.35 ± 2.15% (CS) and + 0.79 ± 3.71% (NCS)). Significant differences were also noted around the knee (cD) at day 10 (p = 0.026) and a significant trend at cD and at the mid lower leg (cB1) at day 4. The volume of the thigh was also different with marked difference between days 1 and 4 between the two groups (p = 0.021; volume + 0.54 ± 2.03% (CS) and + 4.17 ± 4.67 (NCS)). Pain was lower in compression group (not statistically significant).

Conclusions

Post-operative limb swelling can be reduced significantly by wearing compression stockings in the early post-operative phase when compared to not wearing stockings. This may improve the rehabilitation process after arthroscopic surgery. The optimal duration of compression therapy seems to be between three and ten days.

Trial registration

clinicaltrials.gov (NCT02096562, date of registration 11.11.2013).

[Significance of Matrix-augmented Bone Marrow Stimulation for Treatment of Cartilage Defects of the Knee: A Consensus Statement of the DGOU Working Group on Tissue Regeneration]

Surgical principles for treatment of full-thickness cartilage defects of the knee include bone marrow stimulation techniques (i.e. arthroscopic microfracturing) and transplantation techniques (i.e. autologous chondrocyte implantation and osteochondral transplantation). On the basis of increasing scientific evidence, indications for these established therapeutical concepts have been specified and clear recommendations for practical use have been given. Within recent years, matrix-augmented bone marrow stimulation has been established as a new treatment concept for chondral lesions. To date, scientific evidence is limited and specific indications are still unclear. The present paper gives an overview of available products as well as preclinical and clinical scientific evidence. On the basis of the present evidence and an expert consensus from the "Working Group on Tissue Regeneration" of the German Orthopaedic and Trauma Society (DGOU), indications are specified and recommendations for the use of matrix-augmented bone marrow stimulation are given. In principle, it can be stated that the various products offered in this field differ considerably in terms of the number and quality of related studies (evidence level). Against the background of the current data situation, their application is currently seen in the border area between cell transplantation and bone marrow stimulation techniques, but also as an improvement on traditional bone marrow stimulation within the indication range of microfracturing. The recommendations of the Working Group have preliminary character and require re-evaluation after improvement of the study situation.

[Debridement in Focal Cartilage Damage of the knee. Systematical review of the literature and recommendations of the working group "clinical tissue regeneration" of the German Society of Orthopaedics and Trauma (DGOU)]

BACKGROUND

In clinical practice, there is still no definite treatment algorithm for focal, partial thickness cartilage lesions (grade II - III). It is well-established that debridement (shaving/lavage) of large degenerative cartilage lesions is not recommended, but there is no such recommendation in the case of focal, partial thickness cartilage defects.

MATERIALS AND METHODS

The scientific rationale of cartilage shaving and joint lavage was investigated and a systematic analysis was performed of the literature on the clinical effect of cartilage debridement. Furthermore, a consensus statement on this issue was developed by the working group on Clinical Tissue Regeneration of the German Society of Orthopaedics and Trauma (DGOU).

RESULTS

The therapeutic approach is different for asymptomatic lesions with biomechanical stable residual cartilage tissue and clinically symptomatic defects with unstable fragments. The benefit of a joint lavage or surface smoothening of focal partial thickness has not been proved. Even more importantly, the mechanical or thermal resection of cartilage tissue even induces a zone of necrosis in adjacent cartilage, and thus leads to additional injury. Therefore, large scale smoothening (shaving) of clinically asymptomatic, fibrillated or irregular cartilage defects should not be performed. However, if there are clinical symptoms, resection of unstable and delaminated cartilage fragments may be reasonable, as it can reduce harmful shear tension in residual tissue. This can help to brake the progression of the damage and avoid formation of free bodies.

CONCLUSION

The decision criteria for debridement of partial thickness focal cartilage lesions are multifactorial and include the clinical symptoms, the size and the degree of the defect, the stability of remaining cartilage, localisation of the defect, and individual patient-specific parameters. Debridement is not recommended for asymptomatic lesions, but may be reasonable for symptomatic cases with unstable tissue.

Practical execution of defect preparation prior to surgical cartilage intervention: results from a representative meeting survey among experts

During a specialised orthopedic meeting held on ‘the state of the art in cartilage defect repair’, all previously fully-registered participants were requested to participate in an electronic survey by the use of a moderator-presented “Power Point Presentation-based” 9-item questionnaire. The aim of this survey was to assess indication, approach, and treatment execution of cartilage defect debridement prior to planned microfracture (MFX) or autologous chondrocyte implantation (ACI). All participants completed the questionnaire (n = 146) resulting in a return rate of 100 %. An uncertainty exists as to whether the removal of the calcifying layer prior to cartilage repair must be carried out or not. The same was true for the acceptability of subchondral bleeding prior to microfracturing and its handling prior to autologous chondrocyte implantation. There is a degree of unanimity among experts regarding the management of osteophytes and bone marrow edema. In a homogenous society collective of consultants that frequently deal with cartilage defective pathologies, there still remain a significant heterogeneity in selected topics of defect debridement.

Partial weightbearing is not necessary after cementless total hip arthroplasty: a two-year prospective randomized study on 100 patients

The purpose of this study was to evaluate the effects of partial and full weightbearing after cementless total hip arthroplasty over a two year follow-up period. Fifty-nine women and 41 men (average age 61 years) received an uncemented Spotorno stem and were randomised into a full and a partial weightbearing group. No significant difference was found between the groups with regard to the Merle d' Aubigne hip score, VAS pain level, shaft migration or radiographic signs of bony ingrowth. All femoral components seemed radiologically well-fixed and showed bone ingrowth at 24 months. Provided that solid initial fixation is obtained full weightbearing immediately after cementless total hip arthroplasty using a hydroxyapatite-coated Spotorno-type femoral shaft component can be recommended.

Acoustic microscopic analysis of the biological structure of insect wing membranes with emphasis on their waxy surface

The mechanical performance of natural materials depends on the type, and especially the composition of the molecular constituents. They are almost without exception composite materials, whose characteristics are determined by the characteristics of the individual constituents, their shape, their interaction, and in particular their orientation within the natural material. One of the most impressive natural composites is the insect cuticle. This lightweight building material impresses one with its ability to withstand extremely heavy loading. Even the ultrathin (3-10 microm) membranes of insect wings add greatly to the structural stability of the wings. By means of acoustic microscopy, the present study also shows that the thin covering of wax on the membrane is not an accidental material arrangement. Contrary to that of locust wings, dragonfly wing membranes were found to have a criss-cross fiber-like density gradient within to the waxy layer. This density gradient proved to be mechanically relevant in stabilizing the wings.