Calcitonin treatment for osteoarthritis and rheumatoid arthritis - a systematic review and meta-analysis of preclinical data.

Purpose: The aim of this study was to investigate the efficacy of calcitonin (CT) in animal models of experimental osteoarthritis (OA) and rheumatoid arthritis (RA), as new stabilized CT formulations are currently being introduced. Methods: A comprehensive and systemic literature search was conducted in PubMed/MEDLINE and Embase databases to identify articles with original data on CT treatment of preclinical OA and RA. Methodological quality was assessed using the Systematic Review Centre for Laboratory Animal Experimentation's risk of bias tool for animal intervention studies. To provide summary estimates of efficacy, a meta-analysis was conducted for outcomes reported in four or more studies, using a random-effects model. Subgroup analyses were employed to correct for study specifics. Results: Twenty-six studies were ultimately evaluated and data from 16 studies could be analyzed in the meta-analysis, which included the following outcomes: bone mineral density, bone volume, levels of cross-linked C-telopeptide of type I collagen, histopathological arthritis score, and mechanical allodynia. For all considered outcome parameters, CT-treated groups were significantly superior to control groups (P = 0.002; P = 0.01; P < 0.00001; P < 0.00001; P = 0.04). For most outcomes, effect sizes were significantly greater in OA than in RA (P ≤ 0.025). High in-between study heterogeneity was detected. Conclusion: There is preclinical evidence for an antioxidant, anti-inflammatory, antinociceptive, cartilage- and bone-protective effect of CT in RA and OA. Given these effects, CT presents a promising agent for the treatment of both diseases, although the potential seems to be greater in OA.

Deep learning algorithm for fully automated measurement of sagittal balance in adult spinal deformity.

AIM: Deep learning (DL) algorithms can be used for automated analysis of medical imaging. The aim of this study was to assess the accuracy of an innovative, fully automated DL algorithm for analysis of sagittal balance in adult spinal deformity (ASD). MATERIAL AND METHODS: Sagittal balance (sacral slope, pelvic tilt, pelvic incidence, lumbar lordosis and sagittal vertical axis) was evaluated in 141 preoperative and postoperative radiographs of patients with ASD. The DL, landmark-based measurements, were compared with the ground truth values from validated manual measurements. RESULTS: The DL algorithm showed an excellent consistency with the ground truth measurements. The intra-class correlation coefficient between the DL and ground truth measurements was 0.71-0.99 for preoperative and 0.72-0.96 for postoperative measurements. The DL detection rate was 91.5% and 84% for preoperative and postoperative images, respectively. CONCLUSION: This is the first study evaluating a complete automated DL algorithm for analysis of sagittal balance with high accuracy for all evaluated parameters. The excellent accuracy in the challenging pathology of ASD with long construct instrumentation demonstrates the eligibility and possibility for implementation in clinical routine.

Periacetabular Osteotomy with a Modified Fixation Technique Using K-Wires Shows Clinical Results Comparable to Screw Fixation at Mid-Term Follow-Up.

BACKGROUND: The optimal fixation technique in periacetabular osteotomy (PAO) remains controversial. Modified fixation with Kirschner wires (K-wires) was described as a feasible and safe alternative. However, clinical follow-up of patients treated with this technique is lacking. AIMS: To assess patient-reported outcomes (PROMs) in patients treated with PAO with the K-wire fixation technique and to compare it with the screw fixation technique. METHODS: We conducted an analysis of 202 consecutive PAOs at a single university center between January 2015 and June 2017. A total of 120 cases with complete datasets were included in the final analysis. PAOs with K-wire fixation (n = 63) were compared with screw fixation (n = 57). Mean follow-up was 63 ± 10 months. PROMs assessed included the International Hip Outcome Tool (iHOT 12), Subjective Hip Value (SHV), and UCLA activity score (UCLA). Pain and patient satisfaction (NRS) were evaluated. Joint preservation was defined as non-conversion to total hip arthroplasty (THA). RESULTS: Preoperative baseline PROMs in both fixation groups were similar. In both groups, PROMs (p = <0.001) and pain (p = <0.001) improved significantly. Postoperative functional outcome was similar in both groups: iHOT 12 (71.8 ± 25.1 vs. 73 ± 21.1; p = 0.789), SHV (77.9 ± 21.2 vs. 82.4 ± 13.1; p = 0.192), UCLA (6.9 ± 1.6 vs. 6.9 ± 1.9; p = 0.909), and pain (2.4 ± 2.1 vs. 2.0 ± 2.1; p = 0.302). Patient satisfaction did not differ significantly (7.6 ± 2.6 vs. 8.2 ± 2.2; p = 0.170). Conversion to THA was low in both groups (two vs. none; p = 0.497). CONCLUSION: Periacetabular osteotomy with K-wire fixation provided good clinical results at mid-term follow-up, comparable to those of screw fixation. The technique can therefore be considered a viable option when deciding on the fixation technique in PAO.

Impact of Individual Spinopelvic Anatomy on the Localization and Severity of Symptomatic Isthmic Spondylolisthesis.

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVES: Isthmic spondylolisthesis (iSPL) occurs most commonly in L5/S1 and L4/5. This study investigates the association between spinopelvic anatomy and the pathogenesis of iSPL. METHODS: Spinopelvic parameters as well as severity of slip grade were measured in sagittal spine radiographs of symptomatic patients with iSPL in segments L4/5 and L5/S1. Means were calculated and differences between both groups were analyzed. A correlation between the analyzed parameters and degree of slippage was performed. RESULTS: We included 73 subjects in this study; 11 in L4/5 group and 62 in L5/S1 group. Pelvic anatomy significantly differed between L4/5 and L5/S1 iSPL (Pelvic Incidence (PI) 54.8° vs 66.3°, P value = .006; Pelvic Radius (PR) 124.4 mm vs 137.4 mm; P value = .005 and Sacral Table Angle (STA) 101.0° vs 92.2°, P value < .001). The relative degree of slippage was significantly higher in the L5/S1 group (L4/5 29.1% vs L5/S1 40.1%, P value .022). We also observed a significant correlation between pelvic anatomy and the severity of the slip in iSPL at the L5/S1 level. CONCLUSIONS: Pelvic parameters PI and STA play an important role concerning the level of occurrence and severity of iSPL. Spinopelvic anatomy determines the pathogenesis of iSPL.

Validation of the Subjective Spine Value: A new single item score for the assessment of spine-specific function.

BACKGROUND: Spinal function can be assessed through different patient reported outcome measures (PROMs). PURPOSE: The aim of the present study was to evaluate a novel single-item score for the assessment of spinal function: The Subjective Spine Value (SSpV). It was hypothesized that the SSpV correlates with the established scores Oswestry disability index (ODI) and Core Outcome Measures Index (COMI). METHODS: Between 08/2020 and 11/2021 151 consecutive patients were prospectively enrolled and completed a questionnaire with the ODI, COMI as well as the SSpV. Patients were divided into 4 groups depending on their specific pathology (Group 1: Degenerative pathologies, Group 2: Tumor, Group 3: Inflammatory / Infection, Group 4: Trauma). Pearson correlation coefficient was used to evaluate correlation between the SSpV and the ODI and COMI separately. Floor and ceiling effects were evaluated. RESULTS: Overall, the SSpV correlated significantly with both ODI (p = < 0.001; r = - 0.640) and COMI (p = < 0.001; r = - 0.640). This was also observed across all investigated groups (range - 0.420-0.736). No relevant floor or ceiling effects were noticed. CONCLUSIONS: The SSpV is a valid single-item score for the assessment of spinal function. The SSpV offers a useful tool to efficiently assess spinal function in a variety of spinal pathologies. LEVEL OF EVIDENCE: I, prospective cohort study.

Fixation stability and implant-associated complications in periacetabular osteotomy: a comparison of screw and K-wire fixation.

AIMS: The aim of this study was to compare the fixation stability and complications in patients undergoing periacetabular osteotomy (PAO) with either K-wire or screw fixation. PATIENTS AND METHODS: We performed a retrospective study to analyze a consecutive series of patients who underwent PAO with either screw or K-wire fixation. Patients who were treated for acetabular retroversion or had previous surgery on the ipsilateral hip joint were excluded. 172 patients (191 hips: 99 K-wire/92 screw fixation) were included. The mean age at the time of PAO was 29.3 years (16-48) in the K-wire group and 27.3 (15-45) in the screw group and 83.9% were female. Clinical parameters including duration of surgery, minor complications (soft tissue irritation and implant migration) and major complications (implant failure and non-union) were evaluated. Radiological parameters including LCE, TA and FHEI were measured preoperatively, postoperatively and at 3-months follow-up. RESULTS: Duration of surgery was significantly reduced in the K-wire group with 88.2 min (53-202) compared to the screw group with 119.7 min (50-261) (p < 0.001). Soft tissue irritation occurred significantly more often in the K-wire group (72/99) than in the screw group (36/92) (p < 0.001). No group showed significantly more implant migration than the other. No major complications were observed in either group. Postoperative LCE, TA and FHEI were improved significantly in both groups for all parameters (p = < 0.0001). There was no significant difference for initial or final correction for the respective parameters between the two groups. Furthermore, no significant difference in loss of correction was observed between the two groups for the respective parameters. CONCLUSION: K-wire fixation is a viable and safe option for fragment fixation in PAO with similar stability and complication rates as screw fixation. An advantage of the method is the significantly reduced operative time. A disadvantage is the significantly higher rate of implant-associated soft tissue irritation, necessitating implant removal. LEVEL OF EVIDENCE: III, retrospective trial.

Transversus Abdominis Plane Block Reduces Intraoperative Opioid Consumption in Patients Undergoing Periacetabular Osteotomy.

BACKGROUND: Administering intraoperative analgesia in patients undergoing periacetabular osteotomy (PAO) is challenging due to both the relevant surgical approach and osteotomies, which are associated with pain. The aim of this study was to assess the effect of the transversus abdominis plane block (TAPb) on intraoperative opioid consumption and circulation parameters in PAO patients. PATIENTS AND METHODS: We conducted a two-group randomized-controlled trial involving 42 consecutive patients undergoing PAO for symptomatic developmental dysplasia of the hip (DDH) in our department. Patients assigned to the study group received an ultrasound-guided TAPb with 0.75% ropivacaine before the beginning of the surgery and after general anesthesia induction. Patients assigned to the control group did not receive a TAPb. General anesthesia was conducted according to a defined study protocol. The primary endpoint of the study was the intraoperative opioid consumption, measured in morphine equivalent dose (MED). Secondary endpoints were the assessment of intraoperative heart rate, mean arterial pressure (MAP), need for hypotension treatment, and length of hospital stay (LOHS). A total of 41 patients (n = 21 TAPb group, n = 20 control group) completed the study; of these, 33 were women (88.5%) and 8 were men (19.5%). The mean age at the time of surgery was 28 years (18-43, SD ± 7.4). All operations were performed by a single high-volume surgeon and all TAPb procedures were performed by a single experienced senior anesthesiologist. RESULTS: We observed a significantly lower intraoperative opioid consumption in the TAPb group compared to the control group (930 vs. 1186 MED per kg bodyweight; p = 0.016). No significant differences were observed in the secondary outcome parameters. We observed no perioperative complications. CONCLUSION: Ultrasound-guided TAPb significantly reduces intraoperative opioid consumption in patients undergoing PAO.

Correction of severe valgus osteoarthritis by total knee arthroplasty is associated with increased postoperative ankle symptoms.

PURPOSE: The aim of this study was to assess the mid-term clinical outcome of the ankle joint after total knee arthroplasty (TKA) in high-grade valgus osteoarthritis. METHODS: In this case-control study, n = 36 patients with a preoperative mechanical tibiofemoral angle (mTFA) ≥ 15° who underwent TKA between December 2002 and December 2012 were included. The control group (mTFA < 15°) of n = 60 patients was created using case matching. Radiological [mechanical tibiofemoral angle (mTFA) and ankle joint orientation to the ground (G-AJLO)] and clinical parameters [Foot Function Index (FFI), Knee Society Score, Forgotten Joint Score, and Range of Motion (ROM)] were analysed. The mean follow-up time was 59 months (IQR [56, 62]). RESULTS: The degree of correcting the mTFA by TKA significantly correlated with the postoperative FFI (R = 0.95, p < 0.05), although the knee and ankle joint lines were corrected to neutral orientations. A cut-off value of 16.5° [AUC 0.912 (0.85-0.975 95% CI), sensitivity = 0.8, specificity = 0.895] was calculated, above which the odds ratio (OR) for developing ankle symptoms increased vastly [OR 34.0 (9.10-127.02 95% CI)]. ROM restrictions of the subtalar joint displayed a strong significant correlation with the FFI (R = 0.74, p < 0.05), demonstrating that decreased ROM of the subtalar joint was associated with aggravated outcomes of the ankle joint. CONCLUSIONS: In this study, higher degrees of leg axis correction in TKA were associated with increased postoperative ankle symptoms. When TKA is performed in excessive valgus knee osteoarthritis, surgeons should be aware that this might trigger the onset or progression of ankle symptoms, particularly in cases of a stiff subtalar joint. LEVEL OF EVIDENCE: III.

Spinal implant-associated infections: a prospective multicentre cohort study.

This study evaluated the clinical, laboratory, microbiological, radiological and treatment characteristics of patients with early-onset and late-onset spinal implant-associated infections. Patients diagnosed with spinal implant-associated infection between 2015-2019 were prospectively included and treated according to a standardised algorithm. Infections were classified as early-onset (≤6 weeks) and late-onset (>6 weeks). Among 250 patients, 152 (61%) had early-onset and 98 (39%) had late-onset infection. Local inflammatory signs was the most common manifestation in early-onset infections (84%), whereas late-onset infections presented mainly with persisting or increasing local pain (71%). Sonication fluid was more often positive than peri-implant tissue samples (90% vs. 79%; P = 0.016), particularly in late-onset infections (92% vs. 75%; P = 0.005). Predominant pathogens were coagulase-negative staphylococci, Staphylococcus aureus and Cutibacterium spp. Debridement and implant retention was the most common surgical approach in early-onset infections (85%), whereas partial or complete implant exchange was mainly performed in late-onset infections (62%). Of the 250 patients, 220 (88%) received biofilm-active antibiotics, and median treatment duration was 11.7 weeks. Moreover, 49 patients (20%) needed more than one revision for infection and six patients (2.4%) died during hospital stay. Concluding, most spinal implant-associated infections were acquired during surgery and presented within 6 weeks of surgery. Infections presented mainly with local inflammatory signs in early-onset and with persisting or increasing pain in late-onset infections. Sonication was the most sensitive microbiological method, particularly in late-onset infections. Debridement and implant retention was used in well-integrated implants without loosening, independent of the time of infection onset.

Weight-bearing radiography depends on limb loading.

PURPOSE: The mechanical axis of the lower limb has shown to vary between different weight-bearing conditions and change after total knee arthroplasty (TKA). The purpose of this study was to investigate the correlation between mechanical axis alignment in standing long-leg radiographs and limb loading after TKA. METHODS: Mechanical axis of the lower limb and limb loading have been prospectively evaluated in 115 patients 10 days and 3 months after TKA. By the moment of standing long-leg radiography for analysis of the mechanical leg axis, two digital scales separately captured the load of each limb. RESULTS: Mechanical axis changed from an initial - 1° ± 2° valgus alignment to a varus axis of + 1° ± 2° (p < 0.01). This change in alignment was associated with an increase of limb loading from 89.9 ± 10.7 to 93.0 ± 7.0% (p < 0.01). The mechanical axis strongly correlated with relative limb loading at the first and second measurements (r = 0.804, p < 0.001, respectively, r = 0.562, p < 0.001). A significant change in the rate of outliers was registered within the observation period. These alterations and distinctions were much more pronounced in patients with postoperative incomplete extension (n = 15). CONCLUSIONS: The postoperative mechanical axis correlates with limb loading. A clinical relevant change in frontal alignment of the lower limb is associated with increased limb loading after TKA. The actual mechanical axis can only be assessed at physiological limb loading in long-leg radiographs with complete extension at full weight bearing. LEVEL OF EVIDENCE: Diagnostic study, Level II.

Association Between Lumbar Spinal Degeneration and Anatomic Pelvic Parameters.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The objective was to prove the association between anatomic pelvis parameters and specific types of lumbar spinal degeneration. SUMMARY OF BACKGROUND DATA: Different spinopelvic sagittal profile types are suggested to be associated with specific degenerative lumbar spine pathologies. Because pelvic morphology plays a key role defining the spinal shape as well as its load and function it thereby potentially predisposes the development of spinal degeneration. MATERIALS AND METHODS: Patients with symptomatic lumbar spinal degeneration who were surgically treated in 2 spine departments from March 2011 until August 2016 were included in this retrospective analysis. Single-level degenerative pathologies were classified as lumbar disc herniation (LDH), degenerative disc disease (DDD), lumbar spinal stenosis (LSS), and degenerative spondylolisthesis (DSPL). The constant anatomic pelvic parameters pelvic incidence (PI), pelvic radius (PR), and sacral table angle (STA) were assessed in lateral radiographs of the lumbar spine and compared between the pathologies. RESULTS: In total, 249 patients were assigned to the LDH (n=73), DDD (n=67), LSS (n=42), and DSPL (n=67) groups. Group comparisons revealed significant differences in the anatomic pelvic parameters PR (LDH, 139.5±10.8 mm; DDD, 135.9±14.0 mm; LSS, 127.8±14.3 mm; DSPL, 135.8±12.7 mm; P<0.001), PI (LDH, 53.1±10.0 degrees; DDD, 50.0±9.9 degrees; LSS, 54.5±9.6 degrees; DSPL, 57.1±10.8 degrees; P=0.001), and STA (LDH, 95.3±12.7 degrees; DDD, 105.4±9.0 degrees; LSS, 105.9±11.5 degrees; DSPL, 98.6±9.5 degrees; P<0.001). Post hoc tests indicated significant differences between the PR of the LSS group and that of all other subgroups (P<0.012), the PI of the DDD group and that of DSPL (P<0.001), and the STA of the LDH/DSPL groups and that of the LSS/DDD group (P<0.005). CONCLUSIONS: We found all the constant anatomic parameters to be specific for distinct types of degeneration, suggesting pelvis shape is a predisposing factor for their development. LEVEL OF EVIDENCE: Level III.

Biomechanical Properties of First Dorsal Extensor Compartment Regarding Adequacy as a Bone-Ligament-Bone Graft.

Bone-ligament-bone grafts for reconstruction of the scapholunate ligament are a valuable tool to prevent disease progression to carpal collapse. Locally available grafts do not require an additional donor site. The first extensor compartment was evaluated biomechanically regarding its possible use as an autograft. METHODS: Twelve native fresh-frozen, human cadaver specimens were tested by applying axial tension in a Zwick Roell machine. Load to failure, transplant elongation, and bony avulsion were recorded. The load to failure was quantitated in newtons (N) and the displacement in length (millimeters). Parameters were set at distinct points as start of tension, 1 mm stretch and 1.5 mm dissociation, failure and complete tear, and were evaluated under magnified visual control. Although actual failure occurred at higher tension, functional failure was defined at a stretch of 1.5 mm. RESULTS: Mean load at 1 mm elongation was 44.1 ± 28 N and at 1.5 mm elongation 57.5 ± 42 N. Failure occurred at 111 ± 83.1 N. No avulsion of the bony insertion was observed. Half the transplants failed in the central part of the ligament, while the rest failed near the insertion but not at the insertion itself. Analysis of tension strength displayed a wide range from 3.8 to 83.7 N/mm at a mean of 33.4 ± 28.4 N/mm. CONCLUSIONS: The biomechanical tensile properties of the first dorsal extensor compartment are similar to those of the dorsal part of the scapholunate ligament. A transplant with a larger bone stock and a longer ligament may display an advantage, as insertion is possible in the dorsal, easily accessible part of the carpal bones rather than in the arête-like region adjacent to the insertion of the scapholunate ligament. In this study, 1.5 mm lengthening of the bone-ligament-bone transplant was defined as clinical failure, as such elongation will cause severe gapping and is considered as failure of the transplant.

The role of CT scan in postoperative evaluation of distal radius fractures: Retrospective analysis in regard to complications and revision rates.

BACKGROUND: Intraarticular fractures of the distal radius present a challenging problem for surgeons. While preoperative CT scans are considered helpful to understand the type of fracture and to choose an adequate approach, the role of postoperative CT scans is not yet clearly defined. The aim of this study was to analyze indications for postoperative CT scans and to evaluate its potential therapeutic consequence in regard to detection of complications and its influence on revision rates in intraarticular fractures. These findings were used to establish an algorithm to help identifying patients that benefit from a postoperative CT scan. PATIENTS AND METHODS: Ninety-two patients with intraarticular fractures were included. AO type C fractures were seen in about 90% of patients, with type C3 being present in 55% of the patients. According to Frykman's classification type 7 and 8 fractures were found in 93%. Data was analyzed in regard to radiographic results, complications and indication for a postoperative CT scan. RESULTS: Six patients underwent revision surgery. When analyzing data in regard to correlation of radiographs and CT Scans a statistically significant correlation was found. CONCLUSIONS: A high correlation between both imaging techniques can be shown. In inconclusive radiographs, CT scans are recommended to rule out intraarticular screw placement or step offs. Due to the number of patients and the retrospective design, further studies are needed.

Influence of pelvic tilt on functional acetabular orientation.

BACKGROUND: Pelvic tilt influences acetabular orientation (AO). Anatomical AO can be measured in relation to the anterior pelvic plane (APP), functional AO can be calculated relative to table's plane. OBJECTIVE: To assess to what extent functional AO is determined by pelvic tilt and if APP and table plane give equal information for correct AO. METHODS: AO was evaluated by computed tomography (CT) scans of 138 patients. Pelvic tilt, anatomical and functional AO were measured, differences between the two reference planes were calculated. RESULTS: Anatomical and functional acetabular anteversion (AA) were found to be different in 21% of individuals with an enhanced extent of pelvic tilt. Functional AA was increased compared to anatomical AA at high posterior pelvic tilt (p < 0.001). Enlarged anterior tilting of the pelvis reduced APP-related AA (p < 0.002). Anatomical AA positively correlated with pelvic tilt, particularly in females (p < 0.01, correlation coefficient = 0.698, R2 = 0.523). CONCLUSIONS: APP and table plane do not provide equal information about AO at enhanced pelvic tilt. Functional orientation of the acetabulum is dependent on pelvic tilt, which itself is influenced by anatomical AA and should therefore be analyzed for precise AO.

Postoperative Increased Loading Leads to an Alteration in the Radiological Mechanical Axis After Total Knee Arthroplasty.

BACKGROUND: Standing long-leg radiographs allow assessment of the mechanical axis in the frontal plane before and after total knee arthroplasty (TKA). An alteration in loading, and hence in the forces acting on the knee joint, occurs postoperatively. We therefore postulated that the mechanical axis measured in the long-leg standing radiograph would change within the first year after TKA. METHODS: Standing long-leg radiographs of 156 patients were performed 7 days, 3 months, and 12 months after TKA with determination of mechanical axis of the lower limb. RESULTS: Seven days after surgery, the mechanical axis amounted 0.8° ± 1.7° valgus. Three months after the operation, at 1.3° ± 1.3° varus, it was significantly different (P < .001) from the primary measurement. No further alteration in the mechanical axis occurred during the first year after TKA. This difference was even more pronounced (P < .001) in patients with a postoperative lack of complete extension. Seven days after surgery, they had a valgus axis deviation of 1.6° ± 1.6°; after 3 months, the measurement amounted 1.2° ± 1.3° varus. CONCLUSION: Measured by a standing long-leg radiograph, the frontal mechanical axis after TKA changes over time. The predictive power of a standing long-leg radiograph in the first week after surgery is limited because limb loading is altered because of pain and is therefore nonphysiological. The actual mechanical axis resulting after TKA can only be assessed in a standing long-leg radiograph at physiological loading.

ALIF and total disc replacement versus 2-level circumferential fusion with TLIF: a prospective, randomized, clinical and radiological trial.

STUDY DESIGN: Prospective, randomized trial. PURPOSE: The treatment of degenerative disc disease (DDD) with two-level fusion has been associated with a reasonable rate of complications. The aim of the present study was to compare (Hybrid) stand-alone anterior lumbar interbody fusion (ALIF) at L5/S1 with total disc replacement at L4/5 (TDR) as an alternative surgical strategy to (Fusion) 2-level circumferential fusion employing transforaminal lumbar interbody fusion (TLIF) with transpedicular stabilization at L4-S1. METHODS: A total of 62 patients with symptomatic DDD of segments L5/S1 (Modic ≥2°) and L4/5 (Modic ≤2°; positive discography) were enrolled; 31 were treated with Hybrid and 31 with Fusion. Preoperatively, at 0, 12, and a mean follow-up of 37 months, clinical (ODI, VAS) and radiological evaluations (plain/extension-flexion radiographs evaluated for implant failure, fusion, global and segmental lordosis, and ROM) were performed. RESULTS: In 26 of 31 Hybrid and 24 of 31 Fusion patients available at the final follow-up, we found a significant clinical improvement compared to preoperatively. Hybrid patients had significantly lower VAS scores immediately postoperatively and at follow-up compared to Fusion patients. The complication rates were low and similar between the groups. Lumbar lordosis increased in both groups. The increase was mainly located at L4-S1 in the Hybrid group and at L1-L4 in the Fusion group. Hybrid patients presented with increased ROM at L4/5 and L3/4, and Fusion patients presented with increased ROM at L3/4, with significantly greater ROM at L3/4 compared to Hybrid patients at follow-up. CONCLUSIONS: Hybrid surgery is a viable surgical alternative for the presented indication. Approach-related inferior trauma and the balanced restoration of lumbar lordosis resulted in superior clinical outcomes compared to two-level circumferential fusion with TLIF.

Pelvic tilt compensates for increased acetabular anteversion.

PURPOSE: Pelvic tilt determines functional orientation of the acetabulum. In this study, we investigated the interaction of pelvic tilt and functional acetabular anteversion (AA) in supine position. METHODS: Pelvic tilt and AA of 138 individuals were measured by computed tomography (CT). AA was calculated in relation to the anterior pelvic plane (APP) and relative to the table plane. We analysed these parameters for gender-specific and age-related differences. RESULTS: The mean pelvic tilt was -0.1 ± 5.5°. Pelvic sagittal rotation displayed no gender nor age related differences. Females showed higher angles of AA compared with males (20.0° vs 17.2°, p < 0.001; AA relative to the APP). Anterior tilting of the pelvis positively correlated with AA and individuals with high AA had a higher anterior pelvic tilt compared with those with low AA (p < 0.0001; AA relative to the APP). CONCLUSIONS: AA has to be calculated regarding pelvic sagittal rotation for correct acetabular orientation. Pelvic tilt is dependent on acetabular orientation and compensates for increased AA.

Combination of Complement-Dependent Cytotoxicity and Relative Fluorescent Quantification of HLA Length Polymorphisms Facilitates the Detection of a Loss of Heterozygosity.

Loss of heterozygosity (LOH) is a common event in malignant cells. In this work we introduce a new approach to identify patients with loss of heterozygosity in the HLA region either at first diagnosis or after HLA mismatched allogeneic HSCT. Diagnosis of LOH requires a high purity of recipient target cells. FACS is time consuming and also frequently prevented by rather nonspecific or unknown immune phenotype. The approach for recipient cell enrichment is based on HLA targeted complement-dependent cytotoxicity (CDC). Relative fluorescent quantification (RFQ) analysis of HLA intron length polymorphisms then allows analysis of HLA heterozygosity. The approach is exemplified in recent clinical cases illustrating the detection of an acquired allele loss. As illustrated in one case with DPB1, distinct HLA loci in donor and patient were sufficient for both proof of donor cell removal and evaluation of allele loss in the patient's leukemic cells. Results were confirmed using HLA-B RFQ analysis and leukemia-associated aberrant immunophenotype (LAIP) based cell sort. Both results confirmed suspected loss of HLA heterozygosity. Our approach complements or substitutes for FACS-based cell enrichment; hence it may be further developed as novel routine diagnostic tool. This allows rapid recipient cell purification and testing for loss of HLA heterozygosity before and after allogeneic HSCT in easily accessible peripheral blood samples.

A locking contoured plate for distal fibular fractures: mechanical evaluation in an osteoporotic bone model using screws of different length.

Osteoporotic bone with poor mechanical capacity provides limited stability after fixation of ankle fractures. Stabilization with an implant providing increased fixation strength in osteoporotic bone could reduce failure rates of fixation and allow a more functional treatment. The purpose of this study was to evaluate a locking contoured plate for fixation of distal fibular fractures in comparison with a conventional contoured plate in an osteoporotic bone model. Eighty cylinders of osteoporotic bone surrogates were fixed with the two plates. We performed torque-to-failure and cyclic testing experiments using screws of different length with a Zwick/Roell testing machine. The locking system showed higher torque-to-failure and maximum torque levels as compared with the conventional plate in torque-to-failure experiments and torsional cyclic testing. The locking contoured plate provides improved fixation strength in the osteoporotic bone model. The locking system may be appropriate for fixation of distal fibular fractures, especially in osteoporotic bone with poor mechanical capacity.

Kirschner wire fixations for scapholunate dissociation: a cadaveric, biomechanical study.

PURPOSE: To compare 5 different Kirschner wire fixation techniques in terms of the failure loads seen as scapholunate (SL) dissociation in a cadaveric, biomechanical study. METHODS: 10 fresh-frozen, finger-amputated wrists with sectioned SL ligaments from 3 male and 2 female cadavers were tested. The change of SL angle, SL dissociation, and the load to failure of the 5 different Kirschner wire fixation techniques (using 1.4-mm Kirschner wires) were compared using an axial loading testing machine. The techniques were: (1) SL fixation (using one wire), (2) SL fixation (using 2 wires), (3) SL and scaphocapitate (SC) fixation, (4) SL, SC, and capitolunate (CL) fixation, and (5) CL fixation alone. RESULTS: There was no significant difference between SL fixations using one or 2 wires. The force for SL dissociation was significantly greater in the SL-SC fixation than the SL fixation using one wire (p=0.003). The SL-SC-CL fixation was not significantly stronger than the SL-SC fixation. CONCLUSION: The SL-SC fixation achieved adequate stabilisation of both carpal rows with minimal biological impairment.