Adolescent idiopathic scoliosis (AIS) is the most common form of structural spinal deformities that have a radiological lateral Cobb angle - a measure of spinal curvature - of ≥10(°). AIS affects between 1% and 4% of adolescents in the early stages of puberty and is more common in young women than in young men. The condition occurs in otherwise healthy individuals and currently has no recognizable cause. In the past few decades, considerable progress has been made towards understanding the clinical patterns and the three-dimensional pathoanatomy of AIS. Advances in biomechanics and technology and their clinical application, supported by limited evidence-based research, have led to improvements in the safety and outcomes of surgical and non-surgical treatments. However, the definite aetiology and aetiopathogenetic mechanisms that underlie AIS are still unclear. Thus, at present, both the prevention of AIS and the treatment of its direct underlying cause are not possible.

Platelet-leukocyte gel (PLG) contains high concentrations of platelets and leukocytes. As leukocytes play an important role in the innate host-defense, we hypothesized that PLG might have antimicrobial properties. This study investigated the antimicrobial activity of PLG against Staphylococcus aureus and the contribution of myeloperoxidase (MPO), present in leukocytes, in this process. Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) were obtained from whole blood of six donors. PLG was prepared by mixing PRP with autologous (PLG-AT) or bovine thrombin (PLG-BT). Antimicrobial activity of PLG-AT, PLG-BT, PRP, and PPP was determined in a bacterial kill assay. MPO release was measured by ELISA and activity was measured using a MPO activity assay. Cultures showed a rapid decrease in the number of bacteria for both PLG-AT and PLG-BT, which was maximal between 4 and 8 h, to approximately 1% of the bacteria in controls. The effect of PLG-AT was largest and significantly different compared to PRP ( p ¼ 0.004) and PPP ( p < 0.001), however not compared to PLG-BT ( p ¼ 0.093). PLG-AT, PLG-BT, and PRP showed a comparable, gradually increasing MPO release. MPO activity was comparable for all groups and remained stable. No correlation between MPO release, activity, and bacterial kill could be found. PLG appears to have potent antimicrobial capacity, but the role of MPO in this activity is questionable. PLG might represent a useful strategy against postoperative infections. However, additional research should elucidate its exact antimicrobial activity. ß

BackgroundThere is a need for better interpretation of orthopedic treatment effects. Patient-reported outcome measures (PROMs) are already commonly used for patient evaluation. PROMs can be used to determine treatment effects in research as well as in clinical settings by calculating change scores, with pre- and post-treatment evaluation. The smallest detectable change (SDC) and minimal important change (MIC) are two important benchmarks for interpreting these change scores. The purpose was to determine the SDC and the MIC for four commonly used shoulder-related PROMs: Simple Shoulder Test (SST), Disabilities of the Arm, Shoulder and Hand (DASH and QuickDASH), and the Oxford Shoulder Score (OSS).MethodsA cohort of 164 consecutive patients with shoulder problems visiting an orthopedic outpatient clinic completed the SST, DASH, and the OSS at their first visit and 6 months after operative or non-operative treatment. The SDC was calculated with a test re-test protocol (0–2 weeks). For the MIC, change scores (0–6 months of evaluation) were calculated in seven subgroups of patients, according to an additional self-administered ranking of change over time (anchor-based mean change technique). The MIC is defined as the average score of the ‘slightly improved’ group according to the anchor. The QuickDASH was computed from the DASH.ResultsThe SDC of the SST was 2.8, DASH 16.3, QuickDASH 17.1, and OSS 6.0. The MIC change score for the SST was 2.2, DASH 12.4, QuickDASH 13.4, and OSS 6.0.ConclusionThis study shows that on an individual patient-based level, when taking into account SDC and MIC, the change score should exceed 2.8 points for the SST, 16.3 points for the DASH, 17.1 points for the QuickDASH, and 6.0 points for the OSS to have a clinically relevant change on a PROM, which is not due to measurement error.

Pedicle screw fixation is technically demanding and associated with high complication rates. The aim of this study was to identify and quantify the pedicle screw-related complications in 105 consecutive operations. We retrospectively analysed 105 consecutive primary operations. We found complications of varying severity in 54% of the patients. Deep infections were found in 4.7%, all successfully cured by debridement and antibiotics. There were no permanent neurological complications related to the screws. One serious neurological sequela, a T10 paraplegia, was unrelated to screw placement between L3 and S1. Screw misplacement was found in 6.5% of the screws. Screw breakage occurred in 12.4% of the patients, inevitably leading to loss of correction. Reduced spondylolisthesis L5-S1 without anterior support was found to be especially prone to screw breakage. The study confirmed that pedicle screw placement is a technically demanding procedure with a high complication rate. Fortunately, most complications are not severe. Infections can be dealt with by thorough debridement and parenteral antibiotics. Neurological sequelae can be minimised by careful tactile technique. To avoid screw breakage and subsequent loss of correction, anterior support should be provided, through either posterior or anterior lumbar interbody fusion (PLIF or ALIF) techniques, in reduced spondylolisthesis L5-S1.

BackgroundModification of joint tissue damage is challenging in late-stage osteoarthritis (OA). Few options are available for treating end-stage knee OA other than joint replacement.ObjectivesTo examine whether joint distraction can effectively modify knee joint tissue damage and has the potential to delay prosthesis surgery.Methods20 patients (<60 years) with tibiofemoral OA were treated surgically using joint distraction. Distraction (∼5 mm) was applied for 2 months using an external fixation frame. Tissue structure modification at 1 year of follow-up was evaluated radiographically (joint space width (JSW)), by MRI (segmentation of cartilage morphology) and by biochemical markers of collagen type II turnover, with operators blinded to time points. Clinical improvement was evaluated by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Visual Analogue Scale (VAS) pain score.ResultsRadiography demonstrated an increase in mean and minimum JSW (2.7 to 3.6 mm and 1.0 to 1.9 mm; p<0.05 and <0.01). MRI revealed an increase in cartilage thickness (2.4 to 3.0 mm; p<0.001) and a decrease of denuded bone areas (22% to 5%; p<0.001). Collagen type II levels showed a trend towards increased synthesis (+103%; p<0.06) and decreased breakdown (−11%; p<0.08). The WOMAC index increased from 45 to 77 points, and VAS pain decreased from 73 to 31 mm (both p<0.001).ConclusionsJoint distraction can induce tissue structure modification in knee OA and could result in clinical benefit. No current treatment is able to induce such changes. Larger, longer and randomised studies on joint distraction are warranted.

Although any or all of the mentioned factors in this review may play a certain role in the initiation and progression of AIS at a certain stage, the presented material suggests that in the observed deformation, genetics, and the unique mechanics of the fully upright human spine play a decisive role.

Background: 22q11.2 deletion syndrome (22q11.2DS) is caused by recurrent, chromosome specific, low copy repeat mediated copy number losses of chromosome 22q11. The Children’s Hospital of Philadelphia has been involved in the clinical care of individuals with what is now known as 22q11.2DS since our initial report of the association with DiGeorge syndrome in 1982. Methods: We reviewed the medical records on our continuously growing longitudinal cohort of 1,421 patients with molecularly confirmed 22q11.2DS from 1992 to 2018. Results: Most individuals are Caucasian and older than eight years old. The median age at diagnosis was 360 days. The majority of patients (85%) had typical LCR22A-LCR22D deletions, and only 7% of these typical deletions were inherited from a parent harboring the deletion constitutionally. However, 6% of individuals harbored other nested deletions that would not be identified by traditional 22q11.2 FISH, thus requiring an orthogonal technology to diagnose. Major medical problems included immune dysfunction or allergies (77%), palatal abnormalities (67%), congenital heart disease (64%), gastrointestinal difficulties (65%), endocrine dysfunction (>50%), scoliosis (50%), renal anomalies (16%), and airway abnormalities. Median full-scale IQ was 76, with no significant difference between individuals with and without congenital heart disease or hypocalcemia. Characteristic dysmorphic facial features were present in most, but dermatoglyphic patterns of our cohort are similar to normal controls. Conclusions: This is the largest longitudinal study of patients with 22q11.2DS, helping to further describe the condition and aid in diagnosis and management. Further surveillance will likely elucidate additional clinically relevant findings as they age.

the new histological classification for IVD degeneration is a valid instrument for evaluating IVD degeneration in human IVD sections and is suitable for inexperienced and experienced researchers.