Inter- and intraobserver reliability of the Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients

Background

The purpose of this study is to investigate the inter- and intraobserver reliability of Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients.

Materials and methods

Two consultant orthopedic surgeons classified 141 dysplastic hips on 103 standard anterior–posterior pelvis radiographs according to the Crowe and Hartofilakidis classifications. Assessments were performed in random order by each observer on two separate occasions, at least 4?weeks apart. Kappa statistics were used to establish a relative level of agreement between observers for the two readings and between separate readings by the same observer.

Results

At the first readings, interobserver reliability analysis revealed kappa coefficient of 0.71 for the Crowe classification and 0.54 for the Hartofilakidis classification. At the second reading, the kappa coefficient was 0.72 for the Crowe classification and 0.75 for the Hartofilakidis classification. Intraobserver reliability analysis revealed kappa coefficients of 0.71 for the Crowe and 0.80 for the Hartofilakidis classification for observer A, and 0.76 and 0.70 for observer B.

Conclusions

In conclusion, we have found substantial inter- and intraobserver agreement for Crowe classification and substantial to moderate agreement for Hartofilakidis classification in this study. Both classification systems assess the different aspects of developmental dysplasia of hip in adults. Each system has advantages and disadvantages. We suggest using both of these classifications together to increase the accuracy.     

Unilateral versus bilateral fixation for lumbar spinal fusion: a systemic review and meta-analysis

Purpose

The objective of this study was to systematically compare the efficacy and safety of unilateral fixation to bilateral fixation for the lumbar degenerative disease.

Study design

Systematic review and meta-analysis.

Methods

We searched databases including PubMed Central, MEDLINE (from 1966), EMBASE (from 1980), and Cochrane Central Register of Controlled Trials databases for randomized controlled trials or non-randomized controlled trials that compare unilateral fixation with bilateral fixation for the treatment for lumbar disease. Exclusion criteria were non-controlled studies, follow-up <6 months, combined anterior and posterior surgery, lumbar tumors, and non-English writing paper. Methodologic quality was assessed, relevant data were retrieved, and the appropriate meta-analysis was performed. Two review authors independently selected studies, extracted data, and assessed the risk of bias. The main end points included the rate of fusion, visual analogue scale (VAS), Oswestry disability index (ODI), intra-operative blood loss, operating time, and the rate of complications.

Results

A total of seven studies were included in the meta-analysis. Four relevant randomized controlled trials, one prospective study, and two retrospective studies involving 499 patients were identified. Patients in unilateral pedicle fixation group compared with bilateral pedicle screw fixation group on the fusion rate, VAS, ODI scores, and complication rate demonstrated no significant differences (P > 0.05, respectively). However, intra-operative blood loss and operating time in unilateral fixation group were significantly less than bilateral fixation group (P < 0.0001, respectively).

Conclusions

Unilateral fixation seems to be an effective, feasible, and safe procedure in one or two segmental disease when compare with bilateral instrumentation.     

Diagnosing levator avulsions after first delivery by tomographic ultrasound: reliability between observers from different centers

Introduction and hypothesis

To evaluate the interobserver reliability of diagnosing levator avulsions between observers from different centers using tomographic ultrasound imaging (TUI) in women after their first delivery.

Methods

Transperineal ultrasound volume datasets of 40 women 6 months after their first delivery were analyzed by five observers from four different centers. Levator avulsions were diagnosed using TUI and datasets were assessed as optimal or suboptimal image quality and optimal or suboptimal pelvic floor contraction. Cohen’s kappa was used to evaluate the interobserver reliability of diagnosing levator avulsions for the total group, the group with optimal and suboptimal image quality, and the group with optimal and suboptimal pelvic floor contraction. Consensus on the presence or absence of avulsions was scored according to the number of observers who diagnosed an avulsion (0?=?consensus on the absence of avulsion, 1–4?=?avulsion diagnosed by 1 to 4 observers, 5?=?consensus on the presence of avulsion).

Results

For the total group, the interobserver reliability varied widely, with kappa values ranging from ?0.07 to 0.72. Analyzes in the subgroups showed comparable results. Of the women who potentially have an avulsion (avulsion diagnosed by at least one observer), consensus on the presence of an avulsion was reached in 0.0 to 20.0 %. Of the women who potentially have no avulsion (no avulsion diagnosed by at least one observer), consensus on the absence of an avulsion was reached in 46.7 to 85.7 %.

Conclusions

Diagnosing levator avulsions using TUI in women 6 months after their first delivery is strongly observer-dependent and therefore not generalizable.     

Dynamic magnetic resonance imaging to quantify pelvic organ prolapse: reliability of assessment and correlation with clinical findings and pelvic floor symptoms

Introduction and hypothesis

The aim of this study was to assess the interobserver agreement of magnetic resonance imaging (MRI)-based staging of pelvic organ prolapse (POP) and to quantify associations between MRI-based POP staging, findings at pelvic examination, and pelvic floor symptoms.

Methods

This was a cross-sectional study of ten symptomatic POP patients, ten symptomatic patients without POP, and ten nulliparous asymptomatic women. Three different observers performed MRI-based POP staging using the pubococcygeal line (PCL), midpubic line (MPL), perineal line, and H line as references.

Results

The interobserver agreement of MRI-based staging of the anterior and middle compartment was good to excellent. In symptomatic women without prolapse, MRI-based and pelvic-examination-based POP staging were poorly correlated. In none of the women were MRI-based POP Quantification (POP-Q) staging and pelvic floor symptoms strongly associated.

Conclusion

The interobserver agreement of MRI-based POP staging is excellent, but the added clinical value of such staging is questionable due to poor association with clinical findings and pelvic floor symptoms.     

Intra- and Interobserver Reliability of the Eaton Classification for Trapeziometacarpal Arthritis: A Systematic Review

Background

Trapeziometacarpal, or thumb carpometacarpal (CMC), arthritis is a common problem with a variety of treatment options. Although widely used, the Eaton radiographic staging system for CMC arthritis is of questionable clinical utility, as disease severity does not predictably correlate with symptoms or treatment recommendations. A possible reason for this is that the classification itself may not be reliable, but the literature on this has not, to our knowledge, been systematically reviewed.

Questions/purposes

We therefore performed a systematic review to determine the intra- and interobserver reliability of the Eaton staging system.

Methods

We systematically reviewed English-language studies published between 1973 and 2013 to assess the degree of intra- and interobserver reliability of the Eaton classification for determining the stage of trapeziometacarpal joint arthritis and pantrapezial arthritis based on plain radiographic imaging. Search engines included: PubMed, Scopus^®, and CINAHL. Four studies, which included a total of 163 patients, met our inclusion criteria and were evaluated. The level of evidence of the studies included in this analysis was determined using the Oxford Centre for Evidence Based Medicine Levels of Evidence Classification by two independent observers.

Results

A limited number of studies have been performed to assess intra- and interobserver reliability of the Eaton classification system. The four studies included were determined to be Level 3b. These studies collectively indicate that the Eaton classification demonstrates poor to fair interobserver reliability (kappa values: 0.11–0.56) and fair to moderate intraobserver reliability (kappa values: 0.54–0.657).

Conclusions

Review of the literature demonstrates that radiographs assist in the assessment of CMC joint disease, but there is not a reliable system for classification of disease severity. Currently, diagnosis and treatment of thumb CMC arthritis are based on the surgeon’s qualitative assessment combining history, physical examination, and radiographic evaluation. Inconsistent agreement using the current common radiographic classification system suggests a need for better radiographic tools to quantify disease severity.     

Interobserver variability when employing the IUGA/ICS classification system for complications related to prostheses and grafts in female pelvic floor surgery

Introduction and hypothesis

To unify and organize reporting, an International Urogynecological Association (IUGA)/International Continence Society (ICS) expert consortium published terminology guidelines with a classification system for complications related to implants used in female pelvic surgery. We hypothesize that the complexity of the codification system may be a hindrance to precision, especially with decreasing levels of postgraduate expertise.

Methods

Residents, fellows, and attending physicians were asked to code seven test cases taken from published literature. Category, timing, and site components of the classification system were assessed independently and according to the level of training. Interobserver reliability was calculated as percent agreement and Fleiss’ kappa statistic.

Results

A total of 24 participants (6 attending physicians, 3 fellows, and 15 residents) were tested. The percent agreement showed significant variation when classified by level of training. In all categories, attending physicians had the greatest percentage agreement and largest kappa. The most agreement was seen when attending physicians classified mesh complications by time, 71 % agreement with kappa 0.73 [95 % confidence interval (CI) 0.58–0.88]. For the same task, the percentage agreement for fellows was 57 %, kappa 0.55 (95 % CI 0.23–0.87) and with residents 57 %, kappa 0.71([95 % CI 0.64–0.78). Interestingly, the site component of the classification system had the least overall agreement and lowest kappa [0 %, kappa 0.29 (95 % CI 0.26–0.32)] followed by the category component [14 %, kappa 0.48 (95 % CI 0.46–0.5)].

Conclusions

The IUGA/ICS mesh complication classification system has poor interobserver reliability. This trended downward with decreasing postgraduate level; however, we did not have sufficient statistical power to show an association when stratifying by all training levels. This highlights the complex nature of the classification system in its current form and its limitation for widespread clinical and research application.     

How bilateral iliolumbar fusion increases the stability of horizontal osteosynthesis in unstable pelvic ring injuries?

Objective

In type C pelvic ring injuries, the operative stabilization of the posterior ring is absolutely indicated. There exist four different types of operative methods: iliosacral screw fixation, transsacral plate synthesis, ventral plate fixation (primarily for sacroiliac luxations), and local plate synthesis performed on the dorsal cortex of the sacrum. In our current article, we analyzed the stability of fixation methods used together with bilateral iliolumbar techniques.

Methods

We analyzed a finite element pelvic model attached to lumbar 4–5 vertebrae. By imitating a standing position on two feet, we measured the differences in tension and displacement in T1 and T2 thoracic vertebrae fractures with and without iliolumbar fusion in cases of iliosacral screw fixation, transsacral plate synthesis and KFI-H (small fragment-H) plate synthesis.

Results

The osteosynthesises reinforced via Galveston technique were rather stable; the amount of displacement measured in the fracture gap was significantly less than in the cases without iliolumbar fusion. The tension in the implants were below the allowed values, therefore they were capable of withstanding the imposed loads without permanent deformation.

Conclusions

In unilateral pelvis injuries, if a non-weight bearing status cannot be achieved on the injured side, unilateral iliolumbar fusion reinforcement is justified, since the contralateral lower limb must also be non-weight bearing due to the pelvis injury itself. In the case of the most unstable sacrum fracture—“jumper’s fracture”, bilateral iliolumbar fusion is necessary, in which case the patient will be able to bear weight during the early postoperative period.     

Unilateral versus bilateral pedicle screw fixation in short-segment lumbar spinal fusion: a meta-analysis of randomised controlled trials

Objective

We performed this meta-analysis of randomised controlled trials to compare the efficacy and safety of unilateral with bilateral fixation in short-segment lumbar spinal fusion.

Methods

Predefined terms were used to search electronic databases to identify relevant research. Randomised controlled trials (RCTs) published in English and Chinese during 1990–2015 investigating efficacy and safety of unilateral and bilateral fixation in short-segment lumbar spinal fusion were included. Data of fusion rate, complications, visual analogue scale (VAS), Oswestry Disability Index (ODI), estimated blood loss (EBL) and length of hospital stay were extracted and analysed. Two reviewers independently searched information sources, selected eligible research, analysed data and evaluated risk of bias.

Results

Eleven RCTs comprising 756 participants were analysed. There was no significant difference in fusion rate, device-related complication, ODI, VAS and length of hospital stay between bilateral and unilateral groups. The unilateral group had the obvious advantage of reduced blood loss [mean difference (MD)??143.57, 95 % confidence interval (Cl) -206.61 to -80.54, P?<?0.0001) and operation time (MD -52.72, 95 % Cl -73.58 to -31.87, P?<?0.00001).

Conclusion

Unilateral pedicle screw fixation is equally as effective as bilateral pedicle screw fixation in short-segment lumbar spinal fusion and may reduce operation time and blood loss.

     

Interobserver and intraobserver reliability of the classification and diagnosis for ossification of the posterior longitudinal ligament of the cervical spine

Purpose

Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine has been classified into four types by lateral plain radiographs, but the reliability of the classification and of the diagnosis of either cervical OPLL or cervical spondylotic myelopathy (CSM) was unknown. We investigated the interobserver and intraobserver reliability of the classification and diagnosis for OPLL by radiographs and computed tomography (CT) images.

Methods

A total of 16 observers classified each patient’s images into five groups; OPLL continuous, segmental, mixed, circumscribed type, or CSM. To evaluate interobserver reliability, the observers first classified only radiograph images, and next both radiographs and CT images. On another day they followed the same procedure to evaluate intraobserver reliability. We also evaluated interobserver and intraobserver reliability of the diagnosis of either cervical OPLL or CSM.

Results

Interobserver reliability of the classification with radiographs only showed moderate agreement, but interobserver reliability with both radiographs and CT images showed substantial agreement. Intraobserver of reliability the classification was also improved by additional CT images. Interobserver reliability of the diagnosis with both radiographs and CT images was almost similar to with radiographs only. Intraobserver reliability of the diagnosis was improved by additional CT images.

Conclusions

This study suggested that the reliability of the classification and diagnosis for cervical OPLL was improved by additional CT images. We propose that diagnostic criteria for OPLL include both radiographs and CT images.     

An analysis of fusion cage migration in unilateral and bilateral fixation with transforaminal lumbar interbody fusion

Purpose

To investigate if instrumentation (unilateral vs. bilateral fixation) has an effect on the rate of fusion cage migration.

Methods

This clinical study of transforaminal lumbar interbody fusion involved a prospective group of 116 patients who were randomly assigned to either unilateral (n = 57) or bilateral (n = 59) fixation. Fourteen were lost to follow-up (11 from the unilateral group and 3 from the bilateral group).

Results

The unilateral fixation group consisted of 20 male and 26 female patients. In the unilateral group, the mean age was 53.5 years (range, 18–77), and the preoperative diagnosis consisted of degenerative disc disease, with or without herniated disc (n = 44), and degenerative spondylolisthesis with spinal stenosis (n = 2). The bilateral fixation group consisted of 20 male and 36 female patients. In the bilateral group, the mean age was 55.7 years (range, 26–82), and the preoperative diagnosis consisted of degenerative disc disease, with or without herniated disc (n = 40), and degenerative spondylolisthesis with spinal stenosis (n = 16). A total of 17 cases of cage migration were found; of these, 11 were from the unilateral group and 6 from the bilateral group, resulting in rates of cage migration of 23 and 11 % (p = 0.03), respectively. In regard to migration cases, 5 were male and 12 were female. Ages ranged from 27 to 79 years (mean age, 55 years).

Conclusion

We conclude that unilateral fixation is not stable enough to prevent fusion cage migration in some patients who undergo TLIF.     

Anschlusssegmentbeweglichkeit nach monosegmentaler Bandscheibenprothesenimplantation und monosegmentaler Fusion Segment L4/5

Background

Preservation of movement at the treated segment and possible reduction of adjacent segment effects is assumed to be an advantage of non-fusion technologies over fusion. The aim of this study was to compare the segmental range of motion (ROM) at the operative level, the cranial and caudal adjacent levels and the global lumbar spine ROM (L2-S1) after monosegmental fusion and total disc replacement (TDR).

Patients and methods

Radiographic data was collected from 27 patients with level 1 degenerative disc disease operated at level L4/5. The ROM was assessed at the index level (L4/5), the cranial and caudal adjacent level and for the lumbar spine (L2-S1).

Results

In the TDR group no significant changes of lumbar spine ROM (L2–S1) and segmental ROM (index level, cranial and caudal adjacent level) were noticed. In the fusion group there was a significant reduction of lumbar ROM (L2-S1) and index level ROM. Additionally the relative ROM in the adjacent caudal segment significantly increased while no changes were seen in the cranial segment.

Conclusion

The relative ROM was significantly increased in monosegmental fusion at level L4/5 compared to TDR. To what extent this fact may result in early adjacent segment degeneration in cases of fusion compared to TDR is still unknown.     

Endoanal ultrasound for detection of sphincter defects following childbirth

Introduction and hypothesis

The objectives of this study were to estimate the rates of sonographically detected anal sphincter defects within 72 h of childbirth and to evaluate intra- and interobserver agreement using three-dimensional (3-D) endoanal sonography data.

Methods

This is a prospective observational study of primiparous women delivered vaginally. Women without clinically identified anal sphincter lacerations underwent endoanal ultrasonography within 72 h of delivery. Intra- and interobserver agreement for diagnosis of sphincter defects using 3-D endoanal sonography data was calculated using kappa statistics.

Results

The rate of sphincter defects in 107 women undergoing 3-D endoanal sonography was 12 %. Characteristics of women with sonographically detected sphincter defects, compared to those without, included a significantly increased rate of clinically diagnosed second-degree lacerations (54 vs 20 %, p 0.008). The intra- and interobserver agreement for diagnosis of sphincter defects using 3-D endoanal sonography data was 0.82 [confidence interval (CI) 0.66–0.99] and 0.72 (CI 0.54–0.92), respectively.

Conclusions

Anal sphincter defects detected using endoanal sonography are common, occurring in 12 % of primiparous women, and are significantly associated with other less severe perineal lacerations. Overall and combining sonographically detected defects with clinically diagnosed lacerations, we estimate that 17.8 % of primiparous women delivered vaginally sustain anal sphincter injuries. The intraobserver agreement for diagnosis of sphincter defects is very good and the interobserver agreement is good.     

Comparison of unilateral versus bilateral pedicle screw fixation in lumbar interbody fusion: a meta-analysis

Purpose

This is a meta-analysis to compare the clinical results between unilateral and bilateral pedicle screw (PS) fixation in lumbar interbody fusion.

Methods

We included published studies with no language and year restrictions. The criteria which Koes et al. designed in 1995 were used to evaluate the risk of bias of the included studies. All data were analyzed by Review Manager 5.1. The primary outcomes included fusion rate and screw complications, and the secondary outcomes were operative time, blood loss, and hospital time.

Results

A total of five prospective studies with 407 patients were included in the current meta-analysis, and four of them were randomized controlled trials. There was no significant difference between unilateral PS fixation and bilateral PS fixation group in fusion rate and screw complications (fusion rate: OR 0.54, Z = 1.33, P = 0.18, I ² = 0 %; screw complications: OR 1.45, Z = 0.71, P = 0.48; I ² = 44 %). In the secondary outcomes, the operative time (Z = 3.35, P = 0.0008; I ² = 95 %) and blood loss (Z = 4.35, P < 0.0001; I ² = 98 %) was significantly higher in bilateral PS fixation group than in unilateral PS fixation group. Besides, no significant difference was found in hospital time (Z = 1.19, P = 0.24; I ² = 99 %).

Conclusions

In our meta-analysis, we found that unilateral PS fixation in lumbar fusion was as effective as bilateral PS fixation for lumbar degenerative diseases without major instability, no significant difference was found in hospital time, fusion rate and screw complications. In terms of operative time and blood loss, unilateral PS fixation even produced better results.     

Impact of specialty and level of training on CT measurement of femoral version: an interobserver agreement analysis

Background

To determine the interobserver agreement on femoral version measurements between an orthopedic attending, orthopedic senior and junior residents, and an attending radiologist.

Materials and methods

Postoperative computed tomography (CT) scanograms of 267 patients who underwent femoral intramedullary (IM) nailing with corresponding radiology attending reads for femoral version were collected and de-identified. Femoral version measurements performed by a trauma fellowship-trained attending orthopedic surgeon (ORTHO), a senior orthopedic resident (PGY4), a junior orthopedic resident (PGY1), and a musculoskeletal fellowship-trained attending radiologist (RADS) were compared via Pearson’s interclass correlation coefficient to assess interobserver level of agreement.

Results

Version measurements provided by the two attending physicians exhibited the highest level of agreement (r = 0.661, p < 0.01). The orthopedic attending and the senior resident had the next highest level of agreement (r = 0.543, p < 0.01). The first-year orthopedic resident had the weakest agreement across the board: with the orthopedic attending, the radiology attending, and the senior resident.

Conclusion

Regardless of specialty, experience and higher levels of training produce stronger agreement when measuring femoral version. Residents in training, especially those who are junior, produce weak agreement when compared to their senior colleagues.

Level of evidence

Level III, diagnostic study.     

High reliability of an algorithm for choice of implants in hip fracture patients

Purpose

Hip fracture treatment is controversial, with high complication rates. An algorithm for hip fracture surgery has shown reduced reoperation rates, but choice of implant is based on the commonly used fracture classifications, which were previously evaluated to be unreliable. The purpose of this study was to investigate the reliability of the algorithm.

Methods

From two hospitals, four observers (orthopaedic consultant, fellow, resident and intern) used the algorithm to classify into 15 hip fracture types [Garden type I–IV femoral neck including posterior tilt, vertical femoral neck, basocervical and Arbeitsgemeinschaft für Osteosynthesefragen (AO)-31 A1.1 to A3.3 trochanteric fractures] and to choose between five surgical procedures [parallel implants, prosthesis, two-or four-hole sliding hip screw (SHS) and intermedullary (IM) nail]. After individual assessment, each hospital made a consensus decision. Observations were performed twice, ten weeks apart, on pelvic, anteroposterior (AP) and axial X-rays from 100 consecutive patients.

Results

For fracture classification, mean kappa values were 0.60 for intra and 0.62 for interobserver variation, with interobserver variation between hospitals at 0.65. For posterior tilt, mean intraclass correlation coefficient was 0.91 for intra and 0.87 for interobserver variation. For choice of implant type, mean kappa values were 0.86 for both intra and interobserver variation. The two hospital consensus decisions chose same implant in 91 of 100 patients, giving a kappa value at 0.88.

Conclusion

Although hip fracture classification confirmed to be somewhat unreliable in this study, posterior tilt measurement and subsequent choice of implant type by the algorithm was found to be reliable, which opens up the possibility for a more standardized treatment of hip fracture patients between hospitals.     

The effect of additional video documentation to photo documentation in wrist arthroscopies on intra- and interobserver reliability

Introduction

The reproducibility of diagnoses based on photo documents in wrist arthroscopies is limited and is expected to improve through the addition of video documents.

Aim

The purpose of this study was to determine the effect of additional video documentation to photo documentation on intra- and interobserver reliability in wrist arthroscopies.

Materials and methods

Sixty consecutive arthroscopies were documented by photographs of at least eight standard views and videos of the radiocarpal and midcarpal joints. After 3 months, the photographs and then the photographs together with the videos were reevaluated by the surgeon and by two hand surgeons to determine intra- and interobserver reliability. Percentage agreement and kappa coefficients were calculated.

Results

Using videos along with the photographs did not improve reproducibility in general. The assessments of the cartilage status were even worse. Some of the videos were criticized as being too short to allow adequate assessment of the cartilage. Lesions of the TFCC as well as its tension were assessed notably better by the videos, whereas assessment of SL and LT ligaments was not improved by the videos. Intraobserver reliability was better than interobserver reliability.

Conclusion

As long as videos do not meet further quality criteria, they are not able to improve reliability in general. Nevertheless, videos should be used for documentation of the TFCC.     

Does age affect visualization of the levator ani in nulliparous women?

Introduction and hypothesis

Our aim was to assess whether differences in the ages of nulliparous women affect: (1) interobserver reliability, and (2) visualization of the levator ani (LA) muscle subdivisions in nulliparous women using 3D endovaginal ultrasound (3D-EVUS).

Methods

This was a cross-sectional study. Community-dwelling nulliparous women ages 21–70 years were recruited. Participants underwent a standard examination and a 3D-EVUS. LA subdivisions of interest included the puboperinealis, puboanalis, pubococcygeus, puborectalis, and ileococcygeus muscles. Each ultrasound (US) volume was scored using a validated scale and assessed by two observers. Defect severity was scored for each muscle from 0 (no defect) to 6 (complete muscle loss). A summed score of the two sides was grouped as normal (0), minor (1–3), or major (4–6). Bias was examined using Bland–Altman plots. Intraclass coefficients were calculated to report agreement of total scores. Spearman’s rank correlation was used to evaluate the association between age and LA scores.

Results

Eighty nulliparous women were evaluated. Exact agreement for bilateral scoring of each LA subdivision ranged from 82 % to 84 %. Bilateral scoring of the puboperinealis, puborectalis, and ileococcygeus showed moderate to substantial agreement. Bilateral scores of the puboperinealis demonstrated substantial agreement between observers, with an ICC of 0.8 and a mean difference of ?0.2 using the Bland–Altman analysis. When women were analyzed by age decade, reader agreement was overall good to excellent. There was no significant correlation between increasing age and total LA muscle scores (r?=?0.179, p?=?0.113).

Conclusions

Interobserver reliability or visualization of the LA muscle in nulliparous women was not affected by a woman’s age.     

Reliability and agreement between fine-cut CT scans and plain radiography in the evaluation of posterolateral fusions.

BACKGROUND CONTEXT: Current imaging techniques used to evaluate fusion status after a posterolateral fusion such as radiographs, computed axial tomography (CT) scans, and tomograms are known to be inaccurate, with error rates estimated from 20% to 40%. Previous studies evaluated CT scans using 2-4-mm thick slices with limited reconstructions. PURPOSE: The purpose of this study is to determine the intraobserver and interobserver agreement of plain radiographs and fine-cut (1-mm) CT scans with sagittal and coronal reconstructions in evaluating fusion status after instrumented posterolateral fusions. The correlation between radiographic evaluations and CT scan evaluations was also analyzed. STUDY DESIGN/SETTING: Cross-sectional, blinded. PATIENT SAMPLE: One-year radiographs and CT scans of 86 patients who had single-level instrumented posterolateral fusions. OUTCOME MEASURES: Fusion grades based on previously published criteria were determined. METHODS: Three spine surgeons graded the fusions of 86 patients who had single-level instrumented posterolateral fusions using 1-year postoperative flexion/extension lateral and anteroposterior radiographs, and fine-cut CT scans with sagittal and coronal reconstructions. The technique used to obtain the radiographs and the CT scans was the same in all cases. Two separate readings, 2 weeks apart, were done on each patient by each surgeon. The kappa coefficients for interobserver and intraobserver variability were determined. RESULTS: The intraobserver agreement using CT scans to assess fusion status was moderate for both classification systems (Molinari=0.48, Glassman 0.47). The intraobserver agreement using X-rays to assess fusion status was fair for the Molinari classification (kappa=0.37) and moderate for the Glassman classification (kappa=0.43). The interobserver agreement using CT scans to assess fusion status was moderate for both classification systems (Molinari=0.48, Glassman 0.48). The interobserver agreement using X-rays to assess fusion status was fair for both classification systems (Molinari=0.24, Glassman 0.26). Observers agreed most often when the fusion was assessed as solid (Molinari k=0.61, Glassman k=0.63). The rating on the radiographs and CT scans agreed only 46% to 59% of the time. CONCLUSIONS: Fine-cut CT scans with reconstructions have a considerably greater degree of interobserver and intraobserver agreement compared with flexion/extension and anteroposterior radiographs. Observers agree most often when the fusion is assessed as solid. Fusion evaluation based on radiographs agrees with CT scans only half the time. Future studies are needed to correlate the findings on fine-cut CT scans with surgical exploration.     

Comparative effectiveness of PEEK rods versus titanium alloy rods in lumbar fusion: A preliminary report

Background

Posterior lumbar instruments made of titanium and its alloys could change the physiological distribution of load at the instrumented and adjacent segments, which is a main cause of implant failure, non-fusion and adjacent segment degeneration. Posterior lumbar rods made of polyetheretherketone (PEEK) which is a semirigid alternative to titanium and its alloys have been introduced in lumbar fusion. This prospective study compared the radiological and clinical outcomes of patients undergoing lumbar fusion with PEEK rods versus titanium alloy rods.

Methods

Using transpedicular fixation and lumbar fusion, 21 patients were treated with titanium alloy rods (TI group), and 20 patients with PEEK rods (PEEK group). Radiological and clinical outcomes were evaluated, including the status of the implanted instruments, fusion rate, lumbar lordosis angle (LA), disc space height (DH), visual analog score (VAS) for lower back pain (VAS-BP) and leg pain (VAS-LP), Japanese Orthopedic Association scoring system (JOA score) and complications.

Results

Clinical VAS-BP, VAS-LP and JOA scores were significantly improved at 3 months, 6 months, and 1 year postoperatively as compared with preoperative scores in both groups (p?<?0.05), with similar levels of improvement observed at the same time points postoperatively between the two groups. The overall fusion rate was 100 % at the 1-year follow-up for both groups. No significant differences in lumbar lordosis angle were found preoperatively, 1 week and 1 year postoperatively in both groups (p?>?0.05). The postoperative increase of disc space height and loss of disc space height during the follow-up showed a similar extent of change between both groups (p?>?0.05).

Conclusions

PEEK rods offer a similar radiological and clinical efficacy as titanium alloy rods. PEEK rods, as a semirigid implant with unique characteristics, may be an effective alternative treatment for patients with degenerative lumbar disease in lumbar fusion.