Recovery of ACL function after dynamic intraligamentary stabilization is resultant to restoration of ACL integrity and scar tissue formation.

PURPOSE: Dynamic intraligamentary stabilization (DIS) is recognized as a ligament preserving technique for the treatment of acute anterior cruciate ligament (ACL) injuries. The aim of this study was to assess the integrity and morphology of the recovered ACL after DIS repair. METHODS: The cohort comprised 47 patients with an acute proximal ACL rupture undergoing DIS repair. All patients underwent diagnostic arthroscopy after a minimum postoperative interval of 6 months for semi-quantitative evaluation of ACL integrity, function and scar tissue formation. Tegner, Lysholm and International Knee Documentation Committee (IKDC) scores as well as objective anteroposterior (ap) translation were assessed at 6 weeks, 3-, 6-  and 12 months postoperatively. RESULTS: Full restoration of the ACL volume was affirmed in 30 (63.8%) patients and two-third restoration in 13 (27.7%). Hypertrophic scar formation was observed in 23 (48.9%) patients. Forty-four patients (93.6%) demonstrated sufficient ACL tensioning intraoperatively upon anterior stress. At final follow-up, the median Tegner activity level was 5.5 (3-10), Lysholm and IKDC scores were 100 (64-100) and 94 (55-100) points, respectively. The mean ap-translation differed from the normal knee by 2.1 ± 2.2 mm. Deficient ACL recovery was noted in four patients (8.5%), none of which required secondary reconstructive surgery. CONCLUSION: The results demonstrate that clinical recovery of ACL function after DIS repair is resultant to both restoration of ACL volume and scar tissue formation. Factors influencing the degree of scar tissue formation need further investigation to enable future attempts of guiding a balanced biological healing response. LEVEL OF EVIDENCE: IV.

Dynamic-locking-screw (DLS)-leads to less secondary screw perforations in proximal humerus fractures.

BACKGROUND: Loss of reduction and screw perforation causes high failure rates in the treatment of proximal humerus fractures. The purpose of the present study was to evaluate the early postoperative complications using modern Dynamic Locking Screws (DLS 3.7) for plating of proximal humerus fractures. METHODS: Between 03/2009 and 12/2010, 64 patients with acute proximal humerus fractures were treated by angular stable plate fixation using DLSs in a limited multi-centre study. Follow-up examinations were performed three, six, twelve and twenty-four weeks postoperatively and any complications were carefully collected. RESULTS: 56 of 64 patients were examined at the six-month follow-up. Complications were observed in 12 patients (22%). In five cases (9%), a perforation of the DLS 3.7 occurred. CONCLUSIONS: Despite the use of modern DLS 3.7, the early complications after plating of proximal humerus fractures remain high. The potential advantage of the DLS 3.7 regarding secondary screw perforation has to be confirmed by future randomized controlled trials.

Does obesity and nicotine abuse influence the outcome and complication rate after open-wedge high tibial osteotomy? A retrospective evaluation of five hundred and thirty three patients.

PURPOSE: Nicotine abuse and obesity are well-known factors leading to common post-operative complications. However, their influence on the outcome after high tibial osteotomy is controversial. Thus, the aim of this study was to evaluate their effect on the clinical outcome with particular regard to bone non-union and local complications. METHODS: The functional outcome after open-wedge high tibial osteotomy using the TomoFix® plate was assessed by means of the 12-item Oxford knee score in a multicentre study. In addition the intra- and post-operative complications were determined. RESULTS: Of 533 eligible patients, 386 were interviewed after a mean follow-up of 3.6 years. The median Oxford knee score was 43 points (max. 48 points). Six per cent of these patients experienced at least one local post-operative complication. Patients with a body mass index (BMI) of up to 25 and between 25 and 30 had a higher mean score by 3.5 and 1.8 points, respectively, compared with those having a BMI of more than 30 showing a score of 37.5. No correlation was observed between smoking and the functional outcome. Smoking habits, BMI, the absolute patient weight and the interaction term between smoking and BMI were not significant with reference to the complication rate. CONCLUSIONS: This study reveals favourable mid-term results after high tibial osteotomy in varus osteoarthritis even in patients who smoked and obese patients. The indication in patients with a BMI above 30 should be handled with care due to the slightly inferior outcome, although the complication rate was not increased in these patients.

Effect of Different Primers on Shear Bond Strength of Base Metal Alloys and Zirconia Frameworks.

Ensuring a secure bond between a framework structure and layering composite resin veneer is essential for a long-lasting dental restoration. A variety of primer systems are available to facilitate the adhesive bonding. Nevertheless, the growing preference for efficiency and simplicity in dentistry has made the one-bottle universal primers a desirable option. This study aims to compare the effectiveness of universal primers on the shear bond strength (SBS) of base metal alloy (BMA) and zirconia to layering composite resin. Each 160 BMA and zirconia 20 × 10 × 5 mm test specimen was fabricated. Eight different primers (SunCera Metal Primer, Metal Primer Z, Reliance Metal Primer, Alloy Primer, MKZ Primer, Monobond Plus, ArtPrime Plus, and Clearfil Ceramic Primer Plus) were applied to 20 specimens in each group. Subsequently, a 5 × 2 mm composite resin build-up was applied. SBS tests were performed after 24 h of water storage and after thermocycling (25,000 cycles, 5-55 °C). On BMA, after water storage for 24 h, the bond strength values ranged from 26.53 ± 3.28 MPa (Metal Primer Z) to 29.72 ± 2.00 MPa (MKZ Primer), while after thermocycling, bond strength values ranged from 25.19 ± 1.73 MPa (MKZ Primer) to 27.69 ± 2.37 MPa (Clearfil Ceramic Primer Plus). On a zirconia base, after 24 h, the bond strengths values ranged from 22.63 ± 2.28 MPa (Reliance Primer) to 29.96 ± 2.37 MPa (MKZ Primer) and from 23.77 ± 3.86 MPa (Metal Primer Z) to 28.88 ± 3.09 MPa (Monobond Plus) after thermocycling. While no significant difference in bond strength was found between the primers on the BMA base, five primer combinations differed significantly from each other on zirconia (p = 0.002-0.043). All primers achieved a bond strength greater than 23 MPa on both framework materials after thermocycling. Thus, all primers tested can be applied to both framework materials with comparable results.

Outcome after high tibial open-wedge osteotomy: a retrospective evaluation of 533 patients.

PURPOSE: Open-wedge valgus high tibial osteotomy is a well-established procedure in the management of medial osteoarthritis of the knee. In recent years, improved osteotomy and fixation methods have led to an increased use of this technique. The aim of this study was to identify predictive parameters for the clinical outcome after valgus high tibial osteotomy. METHODS: A multicentre case series involving retrospective capture of baseline data and prospective outcome assessment of patients with knee OA who underwent an osteotomy using Tomofix(®) plate was conducted. Functional outcome was assessed using Oxford 12-item Knee Score. RESULTS: Before surgery, the majority of patients had grade III (52%) and grade IV (33%) lesions according to Outerbridge classification. Three hundred and eighty-six of 533 eligible patients were interviewed for follow-up after an average of 3.6 years. The mean Oxford Knee Score was 43 points. Six per cent experienced at least one local postoperative complication. There was a tendency towards lower score results in patients with a higher preoperative degree of the medial cartilage lesion. No correlation between patient age and the Oxford Knee Score was observed. CONCLUSION: Being male, being operated by an experienced surgeon, having no intake of pain medication at follow-up and having no postoperative complication are positive predictors of the Oxford Knee Score up to 5 years after surgery. This study reveals favourable midterm results after valgus high tibial osteotomy in varus osteoarthritis, even in older patients with high degree of cartilage damage. LEVEL OF EVIDENCE: II.

Current concepts review: septic arthritis of the knee pathophysiology, diagnostics, and therapy.

Treatments for bacterial arthritis of the knee joint are arthroscopic irrigation and debridement with systemic antibiotic medication. This article summarizes the relevant data of pathophysiology, stage of infection, symptoms, and diagnostics as well as stage-dependent treatment of bacterial arthritis of the knee joint. The major treatment principles are joint decompression, elimination of the causative organisms by intensive irrigation of the joint with elimination of proteolytic and lysosomal enzymes. Debridement of necrotic soft tissues with the aim of preserving the synovial membrane as an immune-competent structure, and a natural barrier, is recommended. Good results in treating knee infections have been achieved with arthroscopic joint revision and stage-dependent surgical therapy. The infection staging I-IV suggested by Gächter was used most commonly, which mainly reflects the pathophysiologic infection stages. For stages I-III, arthroscopic joint decompression with joint irrigation and debridement is effective and can be repeated in cases of persisting infection. The incidence of repeated arthroscopic joint irrigation depends on the initial stage of the infection and varies between 0 and 41% of the cases. For stage IV infections, the open revision is needed or in seldom cases of therapy failure under initial or repeated arthroscopic joint revision. The success rate of healing infections by arthroscopic irrigation was high with 90-100%.