Risk factors for neurophysiological events related to intraoperative halo-femoral traction in spinal deformity surgery.

PURPOSE: This study identifies risk factors for neurophysiological events caused by intraoperative halo-femoral traction (IOHFT) in patients with adolescent idiopathic scoliosis (AIS), and neuromuscular scoliosis (NMS). METHODS: Neurophysiological integrity was monitored using motor evoked potentials (MEPs). IONM event was defined as a decreased MEP amplitude of more than 80% of baseline in, at least, one muscle. Time between application of IOHFT and event, affected muscles, surgical stage, and time between removal of IOHFT and recovery of MEPs were described. Characteristics (age, height, weight, diagnosis, Cobb angle, and flexibility of the curve) of patients with and without IOHFT-events were compared using analysis of variance. Binary logistic regression analyses were performed to identify predictors. RESULTS: The study included 81 patients (age 15.6 ± 2.4 years, 53 females, AIS: n = 47, NMS n = 34). IOHFT-events occurred in 11 patients (13%; AIS n = 4, NMS n = 7). IOHFTevents affecting all limbs occurred pre-incision in NMS. Events affecting only the legs occurred during all stages of surgery. Patients with IOHFT-events were smaller (p = 0.009) and had stiffer curves (p = 0.046). Height was a predictor (odds ratio, 0.941; 95% confidence interval = 0.896-0.988). All MEPs recovered after removing IOHFT. CONCLUSION: Neurophysiologic events due to IOHFT were common, with the majority in patients with NMS. A shorter stature was a risk factor, and larger Cobb angle and stiffer curve were associated with IOHFT-events. Events occurred at any stage of surgery and involved upper and lower limbs. With an adequate response on IOHFT events, none of the patients had postoperative neurological impairments due to IOHFT.

Outcomes of Nonsurgical Treatments for Symptomatic Adult Degenerative Scoliosis: A Systematic Review.

OBJECTIVE: To evaluate the effectiveness of nonsurgical treatments in symptomatic adult degenerative scoliosis (ADS). DESIGN: A systematic literature review. METHODS: PubMed, Web of Science, and The Cochrane Library were searched to identify research published since 1988. Randomized controlled trials (RCTs) and observational cohort studies were eligible if they featured symptomatic ADS patients aged ≥50 who received nonsurgical treatment. Minimum follow-up was six weeks, and outcomes of interest were pain, disability, quality of life, and Cobb angle. Evidence quality per intervention was rated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. RESULTS: Six studies were included. Of these, four focused specifically on injections, bracing, or yoga; two involved multiple treatments. One RCT provided evidence for greater effectiveness of transforaminal epidural steroid injection over anesthetic alone in reducing radiating pain and disability. Two single-group retrospective cohort studies lent support for bracing to slow curve progression. One retrospective single-group cohort study suggested an association between yoga and reduced curve progression. Evidence for injections to reduce ADS symptoms was rated as low quality; evidence for bracing and yoga was rated as very low quality. No specific evidence was identified regarding other treatments, including physical therapy and analgesics. CONCLUSIONS: Literature describing the effectiveness of nonoperative treatments in symptomatic ADS is scarce. The quantity and quality of the evidence regarding injections, bracing, and yoga are insufficient to advise for or against the use of these methods to improve outcomes in symptomatic ADS. For these and other nonoperative treatment forms, further research is needed.

Comparing Ultrasound-Guided Needling Combined With a Subacromial Corticosteroid Injection Versus High-Energy Extracorporeal Shockwave Therapy for Calcific Tendinitis of the Rotator Cuff: A Randomized Controlled Trial.

PURPOSE: To compare clinical and radiographic outcomes after treatment with standardized high-energy extracorporeal shock wave therapy (ESWT) and ultrasound-guided needling (UGN) in patients with symptomatic calcific tendinitis of the rotator cuff who were nonresponsive to conservative treatment. METHODS: The study was designed as a randomized controlled trial. The ESWT group received ESWT (2000 pulses, energy flux density 0.35 mJ/mm2) in 4 sessions with 1-week intervals. UGN was combined with a corticosteroid ultrasound-guided subacromial bursa injection. Shoulder function was assessed at standardized follow-up intervals (6 weeks and 3, 6, and 12 months) using the Constant Murley Score (CMS), the Disabilities of the Arm, Shoulder, and Hand questionnaire, and visual analog scale for pain and satisfaction. The size, location, and morphology of the deposits were evaluated on radiographs. The a priori sample size calculation computed that 44 participants randomized in each treatment group was required to achieve a power of 80%. RESULTS: Eighty-two patients were treated (56 female, 65%; mean age 52.1 ± 9 years) with a mean baseline CMS of 66.8 ± 12 and mean calcification size of 15.1 ± 4.7 mm. One patient was lost to follow-up. At 1-year follow-up, the UGN group showed similar results as the ESWT group with regard to the change from baseline CMS (20.9 vs 15.7; P = .23), Disabilities of the Arm, Shoulder, and Hand questionnaire (-20.1 vs -20.7; P = .78), and visual analog scale for pain (-3.9 and -2.6; P = .12). The mean calcification size decreased by 13 ± 3.9 mm in the UGN group and 6.7 ± 8.2 mm in the ESWT group (

Predictive factors for brace treatment outcome in adolescent idiopathic scoliosis: a best-evidence synthesis.

PURPOSE: To evaluate predictive factors for brace treatment outcome in adolescent idiopathic scoliosis (AIS) by a systematic review of the literature. METHODS: Eligible studies evaluating one or more predictive factors for brace treatment outcome were included following a systematic search in PubMed and EMBASE on October 23, 2017. Inclusion criteria were: (1) subjects diagnosed with AIS, (2) age ≤ 18 years, (3) treated with a thoraco-lumbo-sacral orthosis (TLSO), and (4) evaluated one or more predictive factors of treatment outcome (failure and/or success). The methodological quality of included studies was independently assessed by two authors. Pooling was not possible due to heterogeneity in statistical analysis. Predictive factors were presented according to a best-evidence synthesis. RESULTS: The literature search identified 26 studies that met the inclusion criteria, and multiple types of TLSO braces were identified (Boston, Wilmington, Chêneau, Osaka Medical College, Dresdner Scoliosis Orthosis and SPoRT). A total of 19 radiographic and 8 clinical predictive factors were reported. Strong evidence was found that lack of initial in-brace correction is associated with treatment failure. Moderate evidence suggests that brace wear time is associated with failure and success, whereas initial curve magnitude and curve type are not. CONCLUSION: The results of this review suggest that lack of initial in-brace correction is strongly associated with brace treatment failure. Future studies on the threshold for minimal immediate in-brace correction, as a potential indication for brace treatment, are recommended. These slides can be retrieved under Electronic Supplementary Material.

The biomechanical effect of single-level laminectomy and posterior instrumentation on spinal stability in degenerative lumbar scoliosis: a human cadaveric study.

OBJECTIVEDegenerative lumbar scoliosis, or de novo degenerative lumbar scoliosis, can result in spinal canal stenosis, which is often accompanied by disabling symptoms. When surgically treated, a single-level laminectomy is performed and short-segment posterior instrumentation is placed to restore stability. However, the effects of laminectomy on spinal stability and the necessity of placing posterior instrumentation are unknown. Therefore, the aim of this study was to assess the stability of lumbar spines with degenerative scoliosis, characterized by the range of motion (ROM) and neutral zone (NZ) stiffness, after laminectomy and placement of posterior instrumentation.METHODSTen lumbar cadaveric spines (T12-L5) with a Cobb angle ≥ 10° and an apex on L3 were included. Three loading cycles were applied per direction, from -4 Nm to 4 Nm in flexion/extension (FE), lateral bending (LB), and axial rotation (AR). Biomechanical evaluation was performed on the native spines and after subsequent L3 laminectomy and the placement of posterior L2-4 titanium rods and pedicle screws. Nonparametric and parametric tests were used to analyze the effects of laminectomy and posterior instrumentation on NZ stiffness and ROM, respectively, both on an individual segment's motion and on the entire spine section. Spearman's rank correlation coefficient was used to study the correlation between disc degeneration and spinal stability.RESULTSThe laminectomy increased ROM by 9.5% in FE (p = 0.04) and 4.6% in LB (p = 0.01). For NZ stiffness, the laminectomy produced no significant effects. Posterior instrumentation resulted in a decrease in ROM in all loading directions (-22.2%, -24.4%, and -17.6% for FE, LB, and AR, respectively; all p < 0.05) and an increase in NZ stiffness (+44.7%, +51.7%, and +35.2% for FE, LB, and AR, respectively; all p < 0.05). The same changes were seen in the individual segments around the apex, while the adjacent, untreated segments were mostly unaffected. Intervertebral disc degeneration was found to be positively correlated to decreased ROM and increased NZ stiffness.CONCLUSIONSLaminectomy in lumbar spines with degenerative scoliosis did not result in severe spinal instability, whereas posterior instrumentation resulted in a rigid construct. Also, prior to surgery, the spines already had lower ROM and higher NZ stiffness in comparison to values shown in earlier studies on nonscoliotic spines of the same age. Hence, the authors question the clinical need for posterior instrumentation to avoid instability.

Patient sexual function and hip replacement surgery: A survey of surgeon attitudes.

PURPOSE: To explore practises of orthopaedic surgeons (and residents) in addressing sexual function (SF) in patients before and after total hip arthroplasty (THA). METHODS: A 26-item questionnaire was sent to health professionals (n = 849); 526 (62.0%) responses were included in the analyses. RESULTS: About 78% of the respondents (77.5%) almost never addressed SF. The most mentioned reason was that "patients do not ask" (47.4%) followed by "I am not aware of possible needs" (38.6%). SF was even less discussed (25.9%) in elderly patients (>60 years). The beneficial effect of THA on SF was rated the highest in retired surgeons (p ≤ 0.001), in which male surgeons scored higher than female surgeons (p = 0.002). The importance of sexual dificulties (SD) in the decision to undergo surgery was rated lowest by residents (p = 0.020). Rating the risk for dislocation varied between occupations (p = 0.008) and gender (p = 0.016), female surgeons rated highest (median 5); 54.1% indicated the orthopaedic surgeon is responsible for providing information about the safe resumption of sexual activity. CONCLUSIONS: Surgeons show little attention to SF related issues in THA patients, which seems not in accordance to patients' needs. Addressing SF increases throughout a surgeon's career. There were divergent views and there is no "common advice" about the safe resumption of sexual activity. The results emphasize the need for guidelines and training in order to encourage addressing SF both, before and after THA.

The efficacy of continuous-flow cryo and cyclic compression therapy after hip fracture surgery on postoperative pain: design of a prospective, open-label, parallel, multicenter, randomized controlled, clinical trial.

BACKGROUND: The number of hip fractures and resulting post-surgical outcome are a major public health concern and the incidence is expected to increase significantly. The acute recovery phase after hip fracture surgery in elder patients is often complicated by severe pain, high morphine consumption, perioperative blood loss with subsequent transfusion and delirium. Postoperative continuous-flow cryocompression therapy is suggested to minimize these complications and to attenuate the inflammatory reaction that the traumatic fracture and subsequent surgical trauma encompass. Based on a pilot study in patients undergoing total hip arthroplasty for osteoarthritis, it is anticipated that patients treated with continuous-flow cryocompression therapy will have less pain, less morphine consumption and lower decrease of postoperative hemoglobin levels. These factors are associated with a shorter hospital stay and better long-term (functional) outcome. METHODS/DESIGN: One hundred and sixty patients with an intra or extracapsular hip fracture scheduled for internal fixation (intramedullary hip nail, dynamic hip screw or cannulated screws) or prosthesis surgery (total hip or hemiarthroplasty) will be included in this prospective, open-label, parallel, multicenter, randomized controlled, clinical superiority trial. Patients will be allocated to two treatment arms: group 'A' will be treated with continuous-flow cryocompression therapy and compared to group 'B' that will receive standard care. Routine use of drains and/or compressive bandages is allowed in both groups. The primary objective of this study is to compare acute pain the first 72 h postoperative, measured with numeric rating scale for pain. Secondary objectives are: (non-) morphine analgesic use; adjusted postoperative hemoglobin level; transfusion incidence; incidence, duration and severity of delirium and use of psychotropic medication; length of stay; location and duration of rehabilitation; functional outcome; short-term patient-reported health outcome; general and cryotherapy related complications and feasibility. DISCUSSION: This is the first randomized controlled trial that will assess the analgesic efficiacy of continuous-flow cryocompression therapy in the acute recovery phase after hip fracture surgery. TRIAL REGISTRATION: www.trialregister.nl, NTR4152 (23(rd) of August 2013).

Does total hip replacement affect sexual quality of life?

BACKGROUND: Total Hip Replacement (THR) is an effective treatment for end-stage hip osteoarthritis. Since the introduction of total joint replacement, the effect on the Sexual Quality of Life (SQoL) following THR has been addressed in scant studies. The aim of our study was to systematically review the literature, to summarise effects of THR on patients' SQoL. METHODS: We searched PubMed, EMBASE and PsycINFO between January 1970 and February 9th, 2015 with search terms including Total Hip, Osteoarthritis, SQoL, and THR. Eligible studies were identified and two independent authors extracted data including details of SQoL, study quality and risk of bias. RESULTS: There were 12 eligible studies, which included a total of 2099 patients with an age range of 20-85 years. The methodological quality of ten studies was rated as low, and of two as moderate. Amongst the majority of patients, SQoL improved after surgery, both in terms of physical-functional and psychosocial well-being. However, changes between pre-operative and postoperative SQoL ranged extensively: for example, Sexual Dysfunction Δ 8-51% and Sexual Activity (SA) Δ 0-77%. Three studies reported that some patients never resumed SA again after surgery. CONCLUSION: In over 40 years of THR treatment, scant studies have examined the effect of THR on patients' SQoL. This review suggests that SQol improves after THR, although the magnitude of effects varies highly. However, the quality of the supporting evidence was rated as low to moderate. This suggests a need for more high quality evidence about the effects of THR on SQoL.

High correlation of the Oxford Knee Score with postoperative pain, but not with performance-based functioning.

PURPOSE: The Oxford Knee Score (OKS) is a widely known patient-related outcome measure (PROM) to determine pain and knee functioning before and after total knee arthroplasty (TKA). Self-reported function is mainly influenced by change in pain; therefore, it was hypothesized that the OKS correlates more with pain than with performance-based functioning. METHODS: In a prospective cohort of 88 patients, who had a cementless mobile-bearing TKA, included in a randomized clinical trial, the correlation between the overall OKS, and its subscales for pain (PCS) and function (FCS), with performance-based functioning using the DynaPort® Knee Score (DKS), visual analogue scale score for pain (VAS) and the Knee Society Score (KSS) was evaluated. All scores were measured preoperatively, 6 months and 1 year after surgery. Overall change in outcome over time was analysed until 5 years after surgery. RESULTS: All scores improved over time. The DKS was influenced by sex, preoperative BMI and age. The internal consistency of the OKS PCS increased over time, whereas the OKS FCS remained the same. The mean postoperative OKS FCS showed moderate correlation with the DKS (r = 0.65, p < 0.001), and the mean postoperative OKS and OKS PCS showed high correlation with the VAS (r = -0.79 and r = -0.82, respectively, p < 0.001). The mean postoperative KSS showed high correlations with the OKS (r = 0.80, p < 0.001), the OKS PCS (r = 0.72 p < 0.001) and OKS FCS (r = 0.74, p < 0.001). CONCLUSION: The postoperative OKS and the OKS PCS showed high correlation with pain, but only the postoperative OKS FCS was well correlated with performance-based functioning. This suggests that the OKS is more related to pain and tells us less on postoperative functioning. This is important when the OKS as PROM is used to evaluate the quality of orthopaedic care of patients with TKA. LEVEL OF EVIDENCE: III.

Spinal fusion using adipose stem cells seeded on a radiolucent cage filler: a feasibility study of a single surgical procedure in goats.

PURPOSE: To assess the feasibility of a one-step surgical concept, employing adipose stem cells (ASCs) and a novel degradable radiolucent cage filler (poly-L-lactide-co-caprolactone; PLCL), within polyetheretherketone cages in a stand-alone caprine spinal fusion model. METHODS: A double-level fusion study was performed in 36 goats. Four cage filler groups were defined: (i) acellular PLCL, (ii) PLCL + SVF (freshly harvested stromal vascular fraction highly enriched in ASCs); (iii) PLCL + ASCs (cultured to homogeneity); and (iv) autologous iliac crest bone graft (ABG). Fusion was assessed after 3 and 6 months by radiography, micro-CT, biomechanics, and biochemical analysis of tissue formed inside the cage after 6 months. RESULTS: No adverse effects were observed in all groups. After 3 months, similar and low fusion rates were found. Segmental stability did not differ between groups in all tested directions. Micro-CT imaging revealed significantly higher amounts of mineralized tissue in the ABG group compared to all others. After 6 months, interbody fusion rates were: PLCL 53%, SVF 30%, ASC 43% and ABG 63%. A trend towards higher mineralized tissue content was found for the ABG group. Biochemical and biomechanical analyses revealed equal maturity of collagen cross-links and similar segmental stability between all groups. CONCLUSIONS: This study demonstrates the technical feasibility and safety of the one-step surgical procedure for spinal fusion for the first time. The radiolucent PLCL scaffold allowed in vivo monitoring of bone formation using plain radiography. Addition of stem cells to the PLCL scaffolds did not result in adverse effects, but did not enhance the rate and number of interbody fusions under the current conditions. A trend towards superior results with ABG was found. Further research is warranted to optimize the spinal fusion model for proper evaluation of both PLCL and stem cell therapy.

MRI T2* mapping correlates with biochemistry and histology in intervertebral disc degeneration in a large animal model.

PURPOSE: To evaluate intervertebral disc (IVD) degeneration and treatments, an objective diagnostic tool is needed. Recently, T2* relaxation time mapping was proposed as a technique to assess early IVD degeneration, yet the correlation with biochemical content and histological features has not been investigated previously. Our objective was to validate T2* mapping for disc degeneration by correlating this technique with accepted parameters of IVD degeneration. METHODS: Mildly and severely degenerated lumbar discs were obtained from an in vivo large animal study; two healthy goat spines were acquired as control. In total, 48 IVDs were analysed using T2-weighted MRI, T2* relaxation time mapping, biochemical assays, macroscopic and histological scoring. Correlations between variables were expressed with Spearman's rho (ρ) coefficients. RESULTS: A complete range of degenerative grades were obtained (mean histological grade 2.2, range 0-6). A linear positive correlation was observed between T2* relaxation time and glycosaminoglycan content (ρ = 0.64, p < 0.001). T2* relaxation time decreased linearly with increasing degeneration as assessed with Pfirrmann scoring system (ρ = -0.67, p < 0.001), macroscopic (ρ = -0.33, p < 0.05) and histological (ρ = -0.45, p < 0.05) grading. CONCLUSIONS: T2* mapping is an MRI technique for IVD evaluation which allows for measurements on a continuous scale thus minimising observer bias compared to grading systems. Although limited by a small sample size, this study showed a relatively good and linear correlation between T2* relaxation time and accepted parameters of disc degeneration. This suggests that T2* mapping is a promising tool to assess disc degeneration in clinical practice.

No clinical benefit of titanium nitride coating in cementless mobile-bearing total knee arthroplasty.

PURPOSE: Titanium nitride (TiN) coating of cobalt-chromium-molybdenum (CoCrMo) implants has shown to improve the biomechanical properties of the implant surface and to reduce adhesive wear in vitro. It is yet unknown whether TiN coating of total knee prosthesis (TKP) affects the postoperative clinical outcome of total knee arthroplasty (TKA). METHODS: In a double-blind randomized controlled clinical trial, 101 patients received an uncemented mobile-bearing CoCrMo TKP, either TiN coated or uncoated. Primary outcome measure visual analogue scale (VAS) score for pain, and secondary outcome measures Knee Society Score (KSS), revision rate and adverse events, range of motion of the knee as well as knee circumference and knee skin temperature were assessed 6 weeks, 6 months, 1 year and 5 years postoperative. Repeated measures analysis was used to evaluate the postoperative outcome measures over time. RESULTS: There was no difference between the two groups in VAS score, KSS, revision rate, range of motion of the knee, knee circumference and knee skin temperature. There were no adverse events that could be related to the TiN coating. CONCLUSIONS: TiN-coated TKP does not influence the postoperative outcome of uncemented mobile-bearing TKA regarding postoperative pain, revision rate, range of motion, swelling and temperature of the knee. Therefore, TiN coating of CoCrMo TKP has no clinical benefit on the outcome of cementless mobile-bearing TKA. LEVEL OF EVIDENCE: Therapeutic study, Level I.

Intradiscal pressure depends on recent loading and correlates with disc height and compressive stiffness.

PURPOSE: Intervertebral discs exhibit time-dependent deformation (creep), which could influence the relation between applied stress and intradiscal pressure. This study investigates the effect of prolonged dynamic loading on intradiscal pressure, disc height and compressive stiffness, and examines their mutual relationships. METHODS: Fifteen caprine lumbar discs with 5 mm of vertebral bone on either side were compressed by 1 Hz sinusoidal load for 4.5 h. After preload, 'High' (130 ± 20 N) or 'Low' (50 ± 10 N) loads were alternated every half hour. Continuous intradiscal pressure measurement was performed with a pressure transducer needle. RESULTS: Each disc showed a linear relationship between axial compression and intradiscal pressure (R (2) > 0.91). The intercept of linear regression analysis declined over time, but the gradient remained constant. Disc height changes were correlated to intradiscal pressure changes (R (2) > 0.98): both decreased during High loading, and increased during Low loading. In contrast, compressive stiffness increased during High loading, and was inversely related to intradiscal pressure and disc height. CONCLUSIONS: Intradiscal pressure is influenced by recent loading due to fluid flow. The correlations found in this study suggest that intradiscal pressure is important for disc height and axial compliance. These findings are relevant for mechanobiology studies, nucleus replacements, finite element models, and ex vivo organ culture systems.

Parsonage-Turner syndrome following post-exposure prophylaxis.

BACKGROUND: The 'Parsonage-Turner syndrome' (PTS) is a rare but distinct disorder with an abrupt onset of shoulder pain, followed by weakness and atrophy of the upper extremity musculature, and a slow recovery requiring months to years. To our best knowledge, this is the first case describing symptoms and signs of PTS following the administration of a post-exposure prophylaxis (PEP) regimen against possible human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infection. CASE PRESENTATION: A 25-year-old Caucasian man presented with pain and unilateral scapular winging following PEP against possible HIV and HBV infection. Although atrophy and weakness were observed for the right supraspinatus muscle, a full range of motion was achievable. Neurological examination, plain radiography of the right shoulder and electromyography showed no additional abnormalities. The patient was diagnosed with post-vaccination PTS and treated non-operatively. During the following 15 months the scapular winging receded and full muscle strength was regained. CONCLUSION: Parsonage-Turner syndrome is a rare clinical diagnosis. The precise pathophysiological mechanism of PTS remains unclear, but it seems to involve an interaction between genetic predisposition, mechanical vulnerability and an autoimmune trigger. An immunological event, such as - in this case - a vaccination as part of PEP treatment, can trigger the onset of PTS. The clinical presentation is distinctive with acute severe pain followed by patchy paresis, atrophy and sensory symptoms that persist for months to years. No currently available tests can provide a definite confirmation or exclusion of PTS. Routine blood examination, electromyography (EMG), and computed tomography (CT) or magnetic resonance imaging (MRI) serve mainly to exclude other disorders. The recovery can be quite lengthy, non-operative treatment is the accepted practice. Supplementary administration of oral prednisolone could shorten the duration of pain. Although the outcome is typically preferable, a substantial amount of patients are left with some residual paresis and functional impairment.

Fracture rate after conventional external beam radiation therapy to the spine in multiple myeloma patients.

BACKGROUND CONTEXT: Conventional external beam radiation therapy (cEBRT) is used in multiple myeloma (MM) to treat severe pain, spinal cord compression, and disease-related bone disease. However, radiation may be associated with an increased risk of vertebral compression fractures (VCFs), which could substantially impair survival and quality of life. Additionally, the use of the Spinal Instability Neoplastic Score (SINS) in MM is debated in MM. PURPOSE: To determine the incidence of VCFs after cEBRT in patients with MM and to assess the applicability of the SINS score in the prediction of VCFs in MM. STUDY DESIGN: Retrospective multicenter cohort study. PATIENT SAMPLE: MM patients with spinal myeloma lesions who underwent cEBRT between January 2010 and December 2021. OUTCOME MEASURES: Frequency of new or progressed VCFs and subdistribution hazard ratios for potentially associated factors. METHODS: Patient and treatment characteristics were manually collected from the patients' electronic medical records. Computed tomography (CT) scans from before and up to 3 years after the start of radiation were used to score radiographic variables at baseline and at follow-up. Multivariable Fine and Gray competing risk analyses were performed to evaluate the diagnostic value of the SINS score to predict the postradiation VCF rate. RESULTS: A total of 127 patients with 427 eligible radiated vertebrae were included in this study. The mean age at radiation was 64 years, and 66.1% of them were male. At the start of radiation, 57 patients (44.9%) had at least one VCF. There were 89 preexisting VCFs (18.4% of 483 vertebrae). Overall, 39 of 127 patients (30.7%) reported new fractures (number of vertebrae (n)=12) or showed progression of existing fractures (n=36). This number represented 11.2% of all radiated vertebrae. Five of the 39 (12.8%) patients with new or worsened VCFs received an unplanned secondary treatment (augmentation [n=2] or open surgery [n=3]) within 3 years. Both the total SINS score (SHR 1.77; 95% confidence interval (CI) 1.54-2.03; p<.001) and categorical SINS score (SHR 10.83; 95% CI 4.20-27.94; p<.001) showed an independent association with higher rates of new or progressed VCFs in adjusted analyses. The use of bisphosphonates was independently associated with a lower rate of new or progressed VCFs (SHR 0.47 [95% CI 0.24-0.92; p=.027]). CONCLUSIONS: This study demonstrated that new or progressed VCFs occurred in 30.7% of patients within 3 years, in a total of 11.2% of vertebrae. The SINS score was found to be independently associated with the development or progression of VCFs and could thus be applied in MM for fracture prediction and possibly prevention.

Torsion biomechanics of the spine following lumbar laminectomy: a human cadaver study.

PURPOSE: Lumbar laminectomy affects spinal stability in shear loading. However, the effects of laminectomy on torsion biomechanics are unknown. The purpose of this study was to investigate the effect of laminectomy on torsion stiffness and torsion strength of lumbar spinal segments following laminectomy and whether these biomechanical parameters are affected by disc degeneration and bone mineral density (BMD). METHODS: Ten human cadaveric lumbar spines were obtained (age 75.5, range 59-88). Disc degeneration (MRI) and BMD (DXA) were assessed. Disc degeneration was classified according to Pfirrmann and dichotomized in mild or severe. BMD was defined as high BMD (≥median BMD) or low BMD (

Which factors prognosticate rotational instability following lumbar laminectomy?

PURPOSE: Reduced strength and stiffness of lumbar spinal motion segments following laminectomy may lead to instability. Factors that predict shear biomechanical properties of the lumbar spine were previously published. The purpose of the present study was to predict spinal torsion biomechanical properties with and without laminectomy from a total of 21 imaging parameters. METHOD: Radiographs and MRI of ten human cadaveric lumbar spines (mean age 75.5, range 59-88 years) were obtained to quantify geometry and degeneration of the motion segments. Additionally, dual X-ray absorptiometry (DXA) scans were performed to measure bone mineral content and density. Facet-sparing lumbar laminectomy was performed either on L2 or L4. Spinal motion segments were dissected (L2-L3 and L4-L5) and tested in torsion, under 1,600 N axial compression. Torsion moment to failure (TMF), early torsion stiffness (ETS, at 20-40 % TMF) and late torsion stiffness (LTS, at 60-80 % TMF) were determined and bivariate correlations with all parameters were established. For dichotomized parameters, independent-sample t tests were used. RESULTS: Univariate analyses showed that a range of geometric characteristics and disc and bone quality parameters were associated with torsion biomechanical properties of lumbar segments. Multivariate models showed that ETS, LTS and TMF could be predicted for segments without laminectomy (r (2) values 0.693, 0.610 and 0.452, respectively) and with laminectomy (r (2) values 0.952, 0.871 and 0.932, respectively), with DXA-derived measures of bone quality and quantity as the main predictors. CONCLUSIONS: Vertebral bone content and geometry, i.e. intervertebral disc width, frontal area and facet joint tropism, were found to be strong predictors of ETS, LTS and TMF following laminectomy, suggesting that these variables could predict the possible development of post-operative rotational instability following lumbar laminectomy. Proposed diagnostic parameters might aid surgical decision-making when deciding upon the use of instrumentation techniques.

Scapular deformity in obstetric brachial plexus palsy and the Hueter-Volkmann law; a retrospective study.

BACKGROUND: The Hueter-Volkmann law describes growth principles around joints and joint deformation. It states that decreased stress leads to increased growth and that excessive stress leads to growth retardation. Aim of this study was to test the possible results of this principle by measuring the effect of dorsal humeral head subluxation on scapular growth in children with Obstetrical Brachial Plexus Lesions (OBPL). According to the Hueter-Volkmann law, subluxation should result in decrease of growth of the dorsal length of the scapula (by increased dorsal pressure) and increase of the ventral length (decreased pressure). METHODS: 58 children (mean age 20 months, range 1-88 month) with unilateral OBPL and good quality MRI of both shoulders were included. On MRI, humeral head subluxation, joint deformation, and ventral and dorsal scapular lengths were measured. Data were expressed as a ratio of the normal side. RESULTS: In affected scapulas both ventral and dorsal side were smaller compared to the normal side. Reduction of growth on the affected side was more marked on the dorsal side than on the ventral side (6.5 mm respectively 4.5 mm, p < 0.001). The balance of growth reduction as expressed by the ratio of ventral and dorsal length was strongly related to subluxation (R(2) = 0.33, p < 0.001) and age (R(2) = 0.19, p < 0.001). CONCLUSIONS: The Hueter-Volkmann law is incompletely active in subluxated shoulders in OBPL. Dorsal subluxation indeed leads to decrease of growth of the dorsal length of the scapula. However, decreased stress did not lead to increased growth of the ventral length of the scapula.

Minimally Invasive Posterior Spinal Nonfusion Surgery in Patients With Adolescent Idiopathic Scoliosis Using a Bipolar One-Way Self-Expanding Rod System: Protocol for a Single-Center Clinical Cohort Study.

BACKGROUND: The current surgical treatment for patients diagnosed with progressive and severe adolescent idiopathic scoliosis (AIS) consists of the correction of the spinal curvature, followed by posterior spinal fusion (PSF). However, research has uncovered short- and long-term complications of posterior spinal fusion in patients with AIS. Minimally invasive growing rod techniques have successfully been used to treat patients with early-onset scoliosis and neuromuscular scoliosis. It may be questioned if minimally invasive posterior spinal nonfusion (PSnF) surgery with bipolar instrumentation can be used for the treatment of AIS. OBJECTIVE: This study will be performed to monitor the efficacy and safety of PSnF surgery by using a commercially available Conformité Européenne-certified spinal implant consisting of bilateral bipolar one-way self-expanding rods (OWSER) for the treatment of patients diagnosed with AIS. METHODS: In 14 selected patients with AIS with Lenke 1-6 curves, minimally invasive PSnF surgery with the OWSER system is performed after the failure of conservative treatment (curve progression of >5° within 1 year). The patients are over 7 years of age, with a major Cobb angle of ≥30°, sufficient flexibility, and a Risser stage of ≤2. Patients will be followed over time, according to the standard medical care. Efficacy will be measured using radiological and patient satisfaction assessments and safety will be determined by the amount of perioperative complications. RESULTS: Patient inclusion started on November 17, 2021 and we hope to finalize patient inclusion by the beginning of 2025. The first results will be expected by the beginning of 2024. CONCLUSIONS: Minimally invasive PSnF in patients with AIS is presented as a less invasive surgical technique that prevents the progression of the scoliotic curve and that allows minor posture correction of coronal imbalance. This will be the first study to examine whether the PSnF bipolar OWSER instrumentation will be the next generation of surgical instrumentation in AIS. TRIAL REGISTRATION: ClinicalTrials.gov NCT04441411; https://clinicaltrials.gov/study/NCT04441411. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47222.

The impact of bone mineral density and disc degeneration on shear strength and stiffness of the lumbar spine following laminectomy.

PURPOSE: Laminectomy is a standard surgical procedure for elderly patients with symptomatic degenerative lumbar stenosis. The procedure aims at decompression of the affected nerves, but it also causes a reduction of spinal shear strength and shear stiffness. The magnitude of this reduction and the influence of bone mineral density (BMD) and disc degeneration are unknown. We studied the influence of laminectomy, BMD, and disc degeneration on shear force to failure (SFF) and shear stiffness (SS). METHODS: Ten human cadaveric lumbar spines were obtained (mean age 72.1 years, range 53-89 years). Laminectomy was performed either on L2 or L4, equally divided within the group of ten spines. BMD was assessed by dual X-ray absorptiometry (DXA). Low BMD was defined as a BMD value below the median. Intervertebral discs were assessed for degeneration by MRI (Pfirrmann) and scaled in mild and severe degeneration groups. Motion segments L2-L3 and L4-L5 were isolated from each spine. SFF and SS were measured, while loading simultaneously with 1,600 N axial compression. RESULTS: Low BMD had a significant negative effect on SFF. In addition, a significant interaction between low BMD and laminectomy was found. In the high BMD group, SFF was 2,482 N (range 1,678-3,284) and decreased to 1,371 N (range 940-1,886) after laminectomy. In the low BMD group, SFF was 1,339 N (range 909-1,628) and decreased to 761 N (range 561-1,221). Disc degeneration did not affect SFF, nor did it interact with laminectomy. Neither low BMD nor the interaction of low BMD and laminectomy did affect SS. Degeneration and its interaction with laminectomy did not significantly affect SS. CONCLUSIONS: In conclusion, low BMD significantly decreased SFF before and after lumbar laminectomy. Therefore, DXA assessment may be an important asset to preoperative screening. Lumbar disc degeneration did not affect shear properties of lumbar segments before or after laminectomy.