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Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_8 | Pages 5 - 5
1 Aug 2022
Wardell D Jayasuriya R Totton N Mills A Breakwell L Cole A
Full Access

Thermal sensors have been used in bracing research as self-reported diaries are inaccurate. Little is known about new low-profile sensors, optimal location within a brace, locational thermal micro-climate and effect of brace lining. Our objective is to Determine an optimal temperature threshold for sensor-measured and true wear time agreement. Identify optimal sensor location. Assess all factors to determine the best sensor option for the Bracing AdoleScent Idiopathic Scoliosis (BASIS) multicentre RCT. Seven Orthotimer and five iButton (DS1925L) sensors were synchronised to record temperature at five-minute intervals. Three healthy participants donned a rigid spinal brace, embedded with both sensors across four anatomical locations (abdomen/axilla/lateral-gluteal/sacral). Universal-coordinated-time wear protocols were performed in/out-doors. Intraclass correlation coefficient (ICC) assessed sensor-measured and true wear time agreement at thresholds 15–36oC. Optimal thresholds, determined by largest ICC estimate: Orthotimer: Abdomen=26oC, axilla=27oC, lateral-gluteal=24.5oC, sacral=22.5oC. iButton: Abdomen=26oC, axilla=27oC, lateral-gluteal=23.5oC, sacral=23.5oC. Warm-up time and error at optimal thresholds increased for moulded sensors covered with 6mm lining. Location: anterior abdominal wall. Excellent reliability and higher optimal thresholds, less likely to be exceeded by ambient temperature; not a pressure area. Sensor: iButton, longer battery life and larger memory than Orthotimer; allows recording at 10 min intervals for life of brace. Orthotimer only able to record every 30 mins, increasing error between true and measured wear time; Orthotimer needs 6-monthly data download. Threshold: 26oC is optimal threshold to balance warm-up and cool-down times for accurately measuring wear time. Sensor should not be covered by lining foam as this significantly prolongs warm-up time


Bone & Joint Open
Vol. 4, Issue 11 | Pages 832 - 838
3 Nov 2023
Pichler L Li Z Khakzad T Perka C Pumberger M Schömig F

Aims. Implant-related postoperative spondylodiscitis (IPOS) is a severe complication in spine surgery and is associated with high morbidity and mortality. With growing knowledge in the field of periprosthetic joint infection (PJI), equivalent investigations towards the management of implant-related infections of the spine are indispensable. To our knowledge, this study provides the largest description of cases of IPOS to date. Methods. Patients treated for IPOS from January 2006 to December 2020 were included. Patient demographics, parameters upon admission and discharge, radiological imaging, and microbiological results were retrieved from medical records. CT and MRI were analyzed for epidural, paravertebral, and intervertebral abscess formation, vertebral destruction, and endplate involvement. Pathogens were identified by CT-guided or intraoperative biopsy, intraoperative tissue sampling, or implant sonication. Results. A total of 32 cases of IPOS with a mean patient age of 68.7 years (37.6 to 84.1) were included. Diabetes, age > 60 years, and history of infection were identified as risk factors. Patient presentation upon admission included a mean body temperature of 36.7°C (36.1 to 38.0), back pain at rest (mean visual analogue scale (VAS) mean 5/10) and when mobile (mean VAS 6/10), as well as elevated levels of CRP (mean 76.8 mg/l (0.4 to 202.9)) and white blood cell count (mean 9.2 units/nl (2.6 to 32.8)). Pathogens were identified by CT-guided or conventional biopsy, intraoperative tissue sampling, or sonication, and Gram-positive cocci presented as the most common among them. Antibiotic therapy was established in all cases with pathogen-specific treatment in 23 (71.9%) subjects. Overall 27 (84.4%) patients received treatment by debridement, decompression, and fusion of the affected segment. Conclusion. Cases of IPOS are rare and share similarities with spontaneous spondylodiscitis. While procedures such as CT-guided biopsy and sonication are valuable tools in the diagnosis of IPOS, MRI and intraoperative tissue sampling remain the gold standard. Research on known principles of PJI such as implant retention versus implant exchange need to be expanded to the field of spine surgery. Cite this article: Bone Jt Open 2023;4(11):832–838


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_9 | Pages 48 - 48
1 Sep 2019
Partridge S Thorpe A Le Maitre C Sammon C
Full Access

Introduction. Injectable hydrogels via minimally invasive surgery reduce the risk of infection, scar formation and the cost of treatment. Degradation of the intervertebral disc (IVD) currently has no preventative treatment. An injectable hydrogel material could restore disc height, reinforce local mechanical properties, and promote tissue regeneration. We present a hydrogel material Laponite. ®. associated poly(N-isopropylacrylamide)-co-poly(dimethylacrylamide) (NPGel). Understanding how the components of this hydrogel system influence material properties, is crucial for tailoring treatment strategies for the IVD and other tissues. Methods & Results. The effect of hydrogel wt./wt., clay and co-monomer percentages were assessed using a box-Behnken design. Rheometry, SEM, FTIR and swelling was used to measure changes in material properties in simulated physiological conditions. Rheometry revealed gelation temperature of hydrogel materials could be modified with dimethyl-acrylamide co-monomer; however, final maximum mechanical properties remained unaffected. Increasing the weight % and clay % increased resultant mechanical properties from ∼500–2500 G' (Pa), increased viscosity, but retained the ability to flow through a 26G needle at 39°C. Discussion & Conclusions. By increasing the weight and clay percentage of the material we can attain greater mechanical properties, this could be beneficial for orthopaedic or even dental applications. By modifying the co-monomer percentage, we can control gelation temperature important for ensuring the material is fully set at 37°C, this could also be utilised to locally deliver drugs from the implanted material. Our current work is focused on comparing our NPGel material formulation with human IVD tissue. Acknowledgements. We would like to thank Arthritis Research UK grant number 21497 for supporting this research. No conflicts of interest. Sources of Funding: Funded by Arthritis Research UK grant number 21497


The Bone & Joint Journal
Vol. 98-B, Issue 1 | Pages 117 - 124
1 Jan 2016
Takenaka S Hosono N Mukai Y Tateishi K Fuji T

Aims. The aim of this study was to determine whether chilled irrigation saline decreases the incidence of clinical upper limb palsy (ULP; a reduction of one grade or more on manual muscle testing; MMT), based on the idea that ULP results from thermal damage to the nerve roots by heat generated by friction during bone drilling. Methods. Irrigation saline for drilling was used at room temperature (RT, 25.6°C) in open-door laminoplasty in 400 patients (RT group) and chilled to a mean temperature of 12.1°C during operations for 400 patients (low-temperature (LT) group). We assessed deltoid, biceps, and triceps brachii muscle strength by MMT. ULP occurring within two days post-operatively was categorised as early-onset palsy. Results. The incidence of ULP (4.0% vs 9.5%, p = 0.003), especially early-onset palsy (1.0% vs 5.5%, p < 0.001), was significantly lower for the LT group than for the RT group. Multivariate analysis indicated that RT irrigation saline use, concomitant foraminotomy, and opened side were significant predictors for ULP. Discussion. Using chilled irrigation saline during bone drilling significantly decreased the ULP incidence, particularly the early-onset type, and shortened the recovery period for ULP. Chilled irrigation saline can thus be recommended as a simple method for preventing ULP. Take home message: Chilled irrigation during laminoplasty reduces C5 palsy. Cite this article: Bone Joint J 2016;98-B:117–24


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 11 | Pages 1478 - 1481
1 Nov 2007
Aono H Ohwada T Kaneko N Fuji T Iwasaki M

Inflammatory markers such as the C-reactive protein (CRP), white blood cell count and body temperature are easy to measure and are used as indicators of infection. The way in which they change in the early post-operative period after instrumented spinal surgery has not been reported in any depth. We measured these markers pre-operatively and at one, four, seven and 14 days postoperatively in 143 patients who had undergone an instrumented posterior lumbar interbody fusion. The CRP proved to be the only sensitive marker and had returned to its normal level in 48% of patients after 14 days. The CRP on day 7 was never higher than that on day 4. Age, gender, body temperature, operating time and blood loss were not related to the CRP level. A high CRP does not in itself suggest infection, but any increase after four days may presage infection


Bone & Joint Open
Vol. 4, Issue 11 | Pages 873 - 880
17 Nov 2023
Swaby L Perry DC Walker K Hind D Mills A Jayasuriya R Totton N Desoysa L Chatters R Young B Sherratt F Latimer N Keetharuth A Kenison L Walters S Gardner A Ahuja S Campbell L Greenwood S Cole A

Aims

Scoliosis is a lateral curvature of the spine with associated rotation, often causing distress due to appearance. For some curves, there is good evidence to support the use of a spinal brace, worn for 20 to 24 hours a day to minimize the curve, making it as straight as possible during growth, preventing progression. Compliance can be poor due to appearance and comfort. A night-time brace, worn for eight to 12 hours, can achieve higher levels of curve correction while patients are supine, and could be preferable for patients, but evidence of efficacy is limited. This is the protocol for a randomized controlled trial of ‘full-time bracing’ versus ‘night-time bracing’ in adolescent idiopathic scoliosis (AIS).

Methods

UK paediatric spine clinics will recruit 780 participants aged ten to 15 years-old with AIS, Risser stage 0, 1, or 2, and curve size (Cobb angle) 20° to 40° with apex at or below T7. Patients are randomly allocated 1:1, to either full-time or night-time bracing. A qualitative sub-study will explore communication and experiences of families in terms of bracing and research. Patient and Public Involvement & Engagement informed study design and will assist with aspects of trial delivery and dissemination.


Aims

In this investigation, we administered oxidative stress to nucleus pulposus cells (NPCs), recognized DNA-damage-inducible transcript 4 (DDIT4) as a component in intervertebral disc degeneration (IVDD), and devised a hydrogel capable of conveying small interfering RNA (siRNA) to IVDD.

Methods

An in vitro model for oxidative stress-induced injury in NPCs was developed to elucidate the mechanisms underlying the upregulation of DDIT4 expression, activation of the reactive oxygen species (ROS)-thioredoxin-interacting protein (TXNIP)-NLRP3 signalling pathway, and nucleus pulposus pyroptosis. Furthermore, the mechanism of action of small interfering DDIT4 (siDDIT4) on NPCs in vitro was validated. A triplex hydrogel named siDDIT4@G5-P-HA was created by adsorbing siDDIT4 onto fifth-generation polyamidoamine (PAMAM) dendrimer using van der Waals interactions, and then coating it with hyaluronic acid (HA). In addition, we established a rat puncture IVDD model to decipher the hydrogel’s mechanism in IVDD.


The Bone & Joint Journal
Vol. 104-B, Issue 9 | Pages 1067 - 1072
1 Sep 2022
Helenius L Gerdhem P Ahonen M Syvänen J Jalkanen J Charalampidis A Nietosvaara Y Helenius I

Aims

The aim of this study was to evaluate whether, after correction of an adolescent idiopathic scoliosis (AIS), leaving out the subfascial drain gives results that are no worse than using a drain in terms of total blood loss, drop in haemoglobin level, and opioid consumption.

Methods

Adolescents (aged between 10 and 21 years) with an idiopathic scoliosis (major curve ≥ 45°) were eligible for inclusion in this randomized controlled noninferiority trial (n = 125). A total of 90 adolescents who had undergone segmental pedicle screw instrumentation were randomized into no-drain or drain groups at the time of wound closure using the sealed envelope technique (1:1). The primary outcome was a drop in the haemoglobin level during first three postoperative days. Secondary outcomes were 48-hour postoperative oxycodone consumption and surgical complications.


Bone & Joint Open
Vol. 3, Issue 5 | Pages 348 - 358
1 May 2022
Stokes S Drozda M Lee C

This review provides a concise outline of the advances made in the care of patients and to the quality of life after a traumatic spinal cord injury (SCI) over the last century. Despite these improvements reversal of the neurological injury is not yet possible. Instead, current treatment is limited to providing symptomatic relief, avoiding secondary insults and preventing additional sequelae. However, with an ever-advancing technology and deeper understanding of the damaged spinal cord, this appears increasingly conceivable. A brief synopsis of the most prominent challenges facing both clinicians and research scientists in developing functional treatments for a progressively complex injury are presented. Moreover, the multiple mechanisms by which damage propagates many months after the original injury requires a multifaceted approach to ameliorate the human spinal cord. We discuss potential methods to protect the spinal cord from damage, and to manipulate the inherent inhibition of the spinal cord to regeneration and repair. Although acute and chronic SCI share common final pathways resulting in cell death and neurological deficits, the underlying putative mechanisms of chronic SCI and the treatments are not covered in this review.


The Bone & Joint Journal
Vol. 104-B, Issue 4 | Pages 495 - 503
1 Apr 2022
Wong LPK Cheung PWH Cheung JPY

Aims

The aim of this study was to assess the ability of morphological spinal parameters to predict the outcome of bracing in patients with adolescent idiopathic scoliosis (AIS) and to establish a novel supine correction index (SCI) for guiding bracing treatment.

Methods

Patients with AIS to be treated by bracing were prospectively recruited between December 2016 and 2018, and were followed until brace removal. In all, 207 patients with a mean age at recruitment of 12.8 years (SD 1.2) were enrolled. Cobb angles, supine flexibility, and the rate of in-brace correction were measured and used to predict curve progression at the end of follow-up. The SCI was defined as the ratio between correction rate and flexibility. Receiver operating characteristic (ROC) curve analysis was carried out to assess the optimal thresholds for flexibility, correction rate, and SCI in predicting a higher risk of progression, defined by a change in Cobb angle of ≥ 5° or the need for surgery.


The Bone & Joint Journal
Vol. 104-B, Issue 1 | Pages 103 - 111
1 Jan 2022
Li J Hu Z Qian Z Tang Z Qiu Y Zhu Z Liu Z

Aims

The outcome following the development of neurological complications after corrective surgery for scoliosis varies from full recovery to a permanent deficit. This study aimed to assess the prognosis and recovery of major neurological deficits in these patients, and to determine the risk factors for non-recovery, at a minimum follow-up of two years.

Methods

A major neurological deficit was identified in 65 of 8,870 patients who underwent corrective surgery for scoliosis, including eight with complete paraplegia and 57 with incomplete paraplegia. There were 23 male and 42 female patients. Their mean age was 25.0 years (SD 16.3). The aetiology of the scoliosis was idiopathic (n = 6), congenital (n = 23), neuromuscular (n = 11), neurofibromatosis type 1 (n = 6), and others (n = 19). Neurological function was determined by the American Spinal Injury Association (ASIA) impairment scale at a mean follow-up of 45.4 months (SD 17.2). the patients were divided into those with recovery and those with no recovery according to the ASIA scale during follow-up.


Bone & Joint Research
Vol. 10, Issue 5 | Pages 328 - 339
31 May 2021
Jia X Huang G Wang S Long M Tang X Feng D Zhou Q

Aims

Non-coding microRNA (miRNA) in extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) may promote neuronal repair after spinal cord injury (SCI). In this paper we report on the effects of MSC-EV-microRNA-381 (miR-381) in a rodent model of SCI.

Methods

In the current study, the luciferase assay confirmed a binding site of bromodomain-containing protein 4 (BRD4) and Wnt family member 5A (WNT5A). Then we detected expression of miR-381, BRD4, and WNT5A in dorsal root ganglia (DRG) cells treated with MSC-isolated EVs and measured neuron apoptosis in culture by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. A rat model of SCI was established to detect the in vivo effect of miR-381 and MSC-EVs on SCI.


The Bone & Joint Journal
Vol. 103-B, Issue 8 | Pages 1392 - 1399
2 Aug 2021
Kang TW Park SY Oh H Lee SH Park JH Suh SW

Aims

Open discectomy (OD) is the standard operation for lumbar disc herniation (LDH). Percutaneous endoscopic lumbar discectomy (PELD), however, has shown similar outcomes to OD and there is increasing interest in this procedure. However despite improved surgical techniques and instrumentation, reoperation and infection rates continue and are reported to be between 6% and 24% and 0.7% and 16%, respectively. The objective of this study was to compare the rate of reoperation and infection within six months of patients being treated for LDH either by OD or PELD.

Methods

In this retrospective, nationwide cohort study, the Korean National Health Insurance database from 1 January 2007 to 31 December 2018 was reviewed. Data were extracted for patients who underwent OD or PELD for LDH without a history of having undergone either procedure during the preceding year. Individual patients were followed for six months through their encrypted unique resident registration number. The primary endpoints were rates of reoperation and infection during the follow-up period. Other risk factors for reoperation and infection were also evalulated.


The Bone & Joint Journal
Vol. 103-B, Issue 3 | Pages 547 - 552
1 Mar 2021
Magampa RS Dunn R

Aims

Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy.

Methods

We carried out a retrospective review of a single surgeon’s prospectively maintained database of cases in which TcMEP monitoring had been used between 2010 and 2017. The upper limbs were used as the control. A true alert was recorded when there was a 50% or more loss of amplitude from the lower limbs with maintained upper limb signals. Patients with true alerts were identified and their case history analyzed.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_15 | Pages 4 - 4
1 Oct 2014
Hughes M Bernard J
Full Access

Costoplasty remains useful in the treatment of adolescent idiopathic scoliosis, rib hump and associated chest wall deformities. However traditional costoplasty increases morbidity and blood loss. We examine the feasibility and possible effectiveness of a more conservative costoplasty using an animal model. 4 fresh half Ovine rib cages from separate animals were obtained, stored at +4 °C and warmed to room temperature before testing. Each rib cage was randomly assigned to group 1, 2, 3 or 4. Ribs 2–10 were dissected out for testing. The ribs then underwent stepwise deconstruction according to their group. Beginning at the convexity, removing first the convex cortex, then the cancellous, then the cranial and caudal cortices to leave just the concave cortex. Testing for stiffness was by three-point bending on the concave side of each rib with the rib fixed at the head of the rib and 5 cm from the resected area. The ribs were deformed at a constant rate of 0.5 mm.sec . −. 1 up to a maximum load of 9.99 kg or until fracturing. Then stress was plotted against strain to find the Young's modulus of each group and statistics carried out with an ANOVA test. The ribs in each group were as follows: Group 1= control, group 2= 30 mm long convex side cortical bone removed 10 mm from lateral tubercle, group 3= convex, cortical and cancellous bone removal and group 4= removal of convex, caudal and cranial cortices with cancellous removal. The Young's Modulus of the groups were: 1= 3.38 N-m (+/− 0.84), 2= 2.65 N-m (+/− 1.58), 3= 1.55 N-m (+/− 0.55) and 4= 0.74 N-m (+/− 0.55). Groups 3 and 4 were significantly less stiff than group 1 (p< 0.01.) No ribs in groups 1, 2 and 4 fractured under the maximum load. 5/8 ribs in group 3 fractured before the maximum load was administered. By deconstructing the rib down to only the concave side it becomes significantly more flexible by approximately 4.5 times than the control Ribs. Coupled with its increase in flexibility it still retains its ability to withstand up to 10 kg of load without fracture. It may be possible to perform a costoplasty whilst preserving ventilatory integrity. This may improve rib hump correction, and curve correction due to increased flexibility of the stiff thoracic cage


Bone & Joint Research
Vol. 9, Issue 5 | Pages 225 - 235
1 May 2020
Peng X Zhang C Bao J Zhu L Shi R Xie Z Wang F Wang K Wu X

Aims

Inflammatory response plays a pivotal role in the pathophysiological process of intervertebral disc degeneration (IDD). A20 (also known as tumour necrosis factor alpha-induced protein 3 (TNFAIP3)) is a ubiquitin-editing enzyme that restricts nuclear factor-kappa B (NF-κB) signalling. A20 prevents the occurrence of multiple inflammatory diseases. However, the role of A20 in the initiation of IDD has not been elucidated. The aim of the study was to investigate the effect of A20 in senescence of TNF alpha (TNF-α)-induced nucleus pulposus cells (NPCs).

Methods

Immunohistochemical staining was performed to observe the expression of A20 in normal and degenerated human intervertebral discs. The NPCs were dissected from the tail vertebrae of healthy male Sprague-Dawley rats and were cultured in the incubator. In the experiment, TNF-α was used to mimic the inflammatory environment of IDD. The cell viability and senescence were examined to investigate the effect of A20 on TNF-α-treated NPCs. The expression of messenger RNA (mRNA)-encoding proteins related to matrix macromolecules (collagen II, aggrecan) and senescence markers (p53, p16). Additionally, NF-κB/p65 activity of NPCs was detected within different test compounds.


The Bone & Joint Journal
Vol. 102-B, Issue 7 | Pages 899 - 903
1 Jul 2020
Bürger J Palmowski Y Strube P Perka C Putzier M Pumberger M

Aims

To evaluate the histopathological examination of peri-implant tissue samples as a technique in the diagnosis of postoperative spinal implant infection (PSII).

Methods

This was a retrospective analysis. Patients who underwent revision spinal surgery at our institution were recruited for this study. PSII was diagnosed by clinical signs, histopathology, and microbiological examination of intraoperatively collected samples. Histopathology was defined as the gold standard. The sensitivity for histopathology was calculated. A total of 47 patients with PSII and at least one microbiological and histopathological sample were included in the study.


The Bone & Joint Journal
Vol. 100-B, Issue 4 | Pages 516 - 521
1 Apr 2018
Qian L Jiang C Sun P Xu D Wang Y Fu M Zhong S Ouyang J

Aims

The aim of this study was to compare the peak pull-out force (PPF) of pedicle-lengthening screws (PLS) and traditional pedicle screws (TPS) using instant and cyclic fatigue testing.

Materials and Methods

A total of 60 lumbar vertebrae were divided into six groups: PLS submitted to instant pull-out and fatigue-resistance testing (groups A1 and A2, respectively), TPS submitted to instant pull-out and fatigue-resistance testing (groups B1 and B2, respectively) and PLS augmented with 2 ml polymethylmethacrylate, submitted to instant pull-out and fatigue-resistance testing (groups C1 and C2, respectively). The PPF and normalized PPF (PPFn) for bone mineral density (BMD) were compared within and between all groups.


Bone & Joint Research
Vol. 6, Issue 4 | Pages 245 - 252
1 Apr 2017
Fu M Ye Q Jiang C Qian L Xu D Wang Y Sun P Ouyang J

Objectives

Many studies have investigated the kinematics of the lumbar spine and the morphological features of the lumbar discs. However, the segment-dependent immediate changes of the lumbar intervertebral space height during flexion-extension motion are still unclear. This study examined the changes of intervertebral space height during flexion-extension motion of lumbar specimens.

Methods

First, we validated the accuracy and repeatability of a custom-made mechanical loading equipment set-up. Eight lumbar specimens underwent CT scanning in flexion, neural, and extension positions by using the equipment set-up. The changes in the disc height and distance between adjacent two pedicle screw entry points (DASEP) of the posterior approach at different lumbar levels (L3/4, L4/5 and L5/S1) were examined on three-dimensional lumbar models, which were reconstructed from the CT images.


Bone & Joint Research
Vol. 5, Issue 9 | Pages 419 - 426
1 Sep 2016
Leichtle CI Lorenz A Rothstock S Happel J Walter F Shiozawa T Leichtle UG

Objectives

Cement augmentation of pedicle screws could be used to improve screw stability, especially in osteoporotic vertebrae. However, little is known concerning the influence of different screw types and amount of cement applied. Therefore, the aim of this biomechanical in vitro study was to evaluate the effect of cement augmentation on the screw pull-out force in osteoporotic vertebrae, comparing different pedicle screws (solid and fenestrated) and cement volumes (0 mL, 1 mL or 3 mL).

Materials and Methods

A total of 54 osteoporotic human cadaver thoracic and lumbar vertebrae were instrumented with pedicle screws (uncemented, solid cemented or fenestrated cemented) and augmented with high-viscosity PMMA cement (0 mL, 1 mL or 3 mL). The insertion torque and bone mineral density were determined. Radiographs and CT scans were undertaken to evaluate cement distribution and cement leakage. Pull-out testing was performed with a material testing machine to measure failure load and stiffness. The paired t-test was used to compare the two screws within each vertebra.