Retroperitoneoscopic debridement and internal fixation for the treatment of lumbar tuberculosis.

ABSTRACT: To describe the retroperitoneoscopic debridement technique and evaluate the clinical outcome of internal fixation for the treatment of lumbar tuberculosis.Twenty-eight patients were performed conventional laparoendoscopic technique (n = 17) or laparoendoscopic single-site technique (n = 11). Antituberculosis chemotherapy and thoracolumbosacral orthosis were given to all patients. The clinical outcomes were evaluated with preoperative and postoperative Visual Analog Scale, and radiographs with respect to sagittal angle and fusion status.Average time of the 28 procedures was 220.6 ±â€Š50.9 min (180-365 min). The average intraoperative blood loss was 108.6 ±â€Š95.3 mL (50-400 mL). All patients showed significant improvement of their Visual Analog Scale back pain score at follow-up and were classified as having a radiographic fusion in this study. The mean sagittal angle was 11.2 ±â€Š3.6° before operation, significantly improved to 3.7 ±â€Š2.4° after operation. There were no recurrent infections during the follow-up period. Complications included loosening of anterior fixation and temporary deficit of the sympathetic nerve.Retroperitoneal laparoscopic approach with CO2 insufflation technique is a challenging but safe and effective procedure for lumbar spine tuberculosis. Retroperitoneal laparoendoscopic single-site can be used for anterior lumbar spine surgery, offer exposure for L1 through L5.

Dual-construct fixation is recommended in ipsilateral femoral neck fractures with infra-isthmus shaft fracture: A STROBE compliant study.

ABSTRACT: The aim of this study was to evaluate the risk factors related to osteosynthesis failure in patients with concomitant ipsilateral femoral neck and shaft fractures, including old age; smoking habit; comminuted fragments; infra-isthmus fracture; angular malreduction; unsatisfactory reduction (fracture gap >5 mm); and treatment with single construct.Patients over the age of 20 with concomitant ipsilateral femoral neck and shaft fractures diagnosed at a level one medical center between 2003 and 2019 were included. Treatment modalities included single construct with/without an antirotational screw for the neck and dual constructs. Radiographic outcomes were assessed from anteroposterior and lateral hip radiographs at follow-up. Fisher exact test was used to analyze categorical variables. The presence of avascular necrosis of the femoral head, delayed union, atrophic or hypertrophic nonunion of the femoral shaft fracture, and loss of reduction were identified as factors related to treatment failure.A total of 22 patients were included in this study. The average age was 58.5 years, and the majority was male (68.2%). The minimum radiographic follow-up duration was 12 months, and the median follow-up time was 12 (interquartile range 12-24) months.Femoral neck osteosynthesis failed in 3 patients, whereas femoral shaft osteosynthesis failed in 12 patients. Fisher exact test demonstrated the failure of femoral shaft osteosynthesis was significantly more frequent in the single-construct cohort in 16 infra-isthmus femoral fracture cases (P = .034).In ipsilateral femoral neck and infra-isthmus shaft fractures, it is better to treat the neck and shaft fractures with separate implants (dual constructs).In a dual-construct cohort, separate plate fixation of the femoral shaft achieved a better result in terms of bone union than retrograde nailing of the shaft (bone union rate: 4/8 vs 0/2).

Temporomandibular joint dislocation in patients with cleft lip and palate after maxillary distraction osteogenesis: Three case reports.

INTRODUCTION: Distraction osteogenesis (DO) is a widely used for cleft and palate related maxillary hypoplasia. There has been little research on temporomandibular joint (TMJ) dislocation after maxillary DO. We present these 3 cases and analyze the possible causes for reference by other clinicians. PATIENT CONCERNS: In the late stages of maxillary DO, the patients gradually felt a decrease in mandibular mobility and suffered from limited mouth opening. Case 2 and 3 could open their mouth up to 1 and 2 fingers and Case 1 barely able to open her mouth at the completion of distraction. DIAGNOSIS: Case 1 and Case 3 were diagnosed as right TMJ dislocation and Case 2 had a TMJ dislocation on her left side. INTERVENTIONS: Patients with TMJ dislocation were repositioned with manipulation as soon as detected. OUTCOMES: There was no recurrence in all three cases during the postoperative follow-up period. CONCLUSIONS: Maxillary DO can sufficiently advance the maxilla in cleft lip and palate patients. Clinicians should be mindful of the TMJ dislocations that maxillary DO can exert on patients.

Biomechanical Evaluation of a Dynamic Stabilization System for the Prevention of Proximal Junctional Failure in Adult Deformity Surgery.

STUDY DESIGN: Biomechanical spine model. Comparison of stress in the implant and the adjacent cranial segment was done with conventional rigid versus dynamic stabilization system (DS) fixation. OBJECTIVE: The aim of this study was to study stress at the proximal end of spinal fixation with a novel DS. SUMMARY OF BACKGROUND DATA: High stress at the implant bone junction may cause proximal junctional failure (PJF) in adult deformity surgery. METHODS: Five life-size spine models were instrumented with pedicle screws and a 5.5-mm Titanium rod from T8-S1. The same models were subsequently instrumented with a similar rod and DS between T8-9 pedicle screws. The spine model was loaded with 25 Nm static load cranial to the proximal fixation in six directions. Strains were measured from the proximal screws. Disc pressure was measured from the proximal instrumented segment (T8-9) and cranial adjacent segment (T7-8). RESULTS: Rigid fixation produced highest strain at T8, followed by T10 then T9. In contrast, DS fixation produced highest strain at T10, followed by T9 then T8. Strain at T8 was significantly less with DS fixation than rigid fixation (P = 0.019). The T10 screw strain was not significantly higher with DS stabilization compared to rigid fixation (P = 0.091). Rigid fixation allowed no load-sharing or pressure rise at T8-9 but an abrupt rise at T7-8. DS system permitted load-sharing and pressure rise in T8-9; the difference compared to rigid fixation was significant in flexion loading (P = 0.04) and similar trend but not significant in extension (P = 0.09). DS system produced a rise in the adjacent segment disc pressure (T7-8), which was smaller than rigid fixation but not significant. CONCLUSION: Long spinal fixation using rigid rods produces maximum stress at the proximal end screw and increases adjacent disc pressure, possibly leading to PJF. Dynamic stabilization at the cranial end segment may prevent PJF by reducing these factors.Level of Evidence: N/A.

Comparison of the Efficiency of Two Novel Guided Bone Regeneration Devices in the Rabbit Calvarial Model.

BACKGROUND: Creating a secluded large space using guided bone regeneration (GBR) is a novel osteogenesis technique used in the prevention of premature membrane exposure complications. However, this technique is not considered clinically feasible. OBJECTIVES: This study aimed to compare the outcome of the insertion of two novel GBR devices in a rabbit calvarial model in terms of mode of action, simplicity, and amount of new space and bone gained. MATERIALS AND METHODS: The expansible GBR (EGBR) device, composed mainly of a titanium plate, silicone membrane, and activation screw, was inserted beneath the periosteum in the calvarial area of eight rabbits. The smart GBR (SGBR) device, composed of silicone sheets and Nitinol strips, were inserted beneath the periosteum in the calvarial area of another 10 rabbits. Half of each group was sacrificed 2 months after surgery, and the other half was sacrificed after 4 months. RESULTS: Histological and microradiographical analysis showed that, at 2 months, the EGBR device achieved a mean space gain of 207.2 mm3, a mean bone volume of 68.2 mm3, and a mean maximum bone height of 1.9 mm. Values for the same parameters at 4 months were 202.1 mm3, 70.3 mm3, and 1.6 mm, respectively. The SGBR device had significantly higher (P < 0.05) mean space gain (238.2 mm3; 239.5 mm3), bone volume (112.9 mm3, 107.7 mm3), and bone height (2.7 mm; 2.6 mm) than the EGBR device at 2 and 4 months, respectively. CONCLUSION: Both devices proved to be effective in augmenting bone vertically through the application of GBR and soft tissue expansion processes. However, the SGBR device was more efficient in terms of mode of action, simplicity, and amount of bone created in the new space.

Imaging evaluation of nano-hydroxyapatite/polyamide 66 strut in cervical construction after 1-level corpectomy: a retrospective study of 520 patients.

BACKGROUND: The application of nano-hydroxyapatite/polyamide 66(n-HA/PA66) struts has become reliable in anterior cervical corpectomy and fusion (ACCF) as a source of sufficient segmental stability. This was a retrospective and long-term imaging evaluation of the n-HA/PA66 strut in 1-level ACCF. METHODS: The patients between June 2006 and December 2014, who underwent 1-level ACCF using an n-HA/PA66 strut, were reviewed. The neurological status was assessed using the Japanese Orthopedic Association (JOA) score and axial pain was evaluated using a Visual Analogue Scale (VAS) score and the radiographic parameters were determined by X-ray and 3-D CT examinations when necessary for the evaluation of bone fusion using the Brantigan scale and imaging characteristics. RESULTS: A total of 520 patients underwent one-level ACCF, with a mean follow-up (FU) duration of 72.38 ± 24.56 months. The level of surgery was C4 in 58 cases, C5 in 173 cases, C6 in 208 cases, and C7 in 81 cases. According to the Brantigan scale, on X-ray examination, the bony fusion rate was observed to be 40%, 70%, 93%, and 98% at 3 months, 6 months, 1 year and the final FU. An interesting radiographic appearance of the bone graft growth pattern was classified into three types. 95% of the patients accounted for types a and b. No significant differences were observed in age, hospitalization duration, surgical haemorrhage volume, or fusion rate among the types except in the percentage and sex of the patients among the types. Type a had better cervical lordosis, and less subsidence than types b and c (P < 0.05). No significant difference was found in segment angle between type a and type b. Type c was more often observed with subsidence rate, segmental angle loss and cervical alignment loss than types a and b (P < 0.05). Type a also had a slightly higher fusion rate, than types b and c, but there were no significant differences. The overall mean JOA score at the final follow-up among the groups were significantly improved comparing that preoperatively and no significant differences were found among the groups, no matter pre-operation or final follow-up. The overall mean VAS score at the final follow-up among the groups were significantly improved comparing that preoperatively and no significant differences in preoperative VAS score were found among the groups. However, the VAS score at the final follow-up of type a or type b was better than type c. No patients received revision surgery. CONCLUSIONS: The type a bone graft growth pattern could allow a lower incidence of subsidence and better maintenance of local and global alignment to be achieved and is thus proposed for surgeons.

PEEK versus titanium cages in lateral lumbar interbody fusion: a comparative analysis of subsidence.

OBJECTIVE: The authors have provided a review of radiographic subsidence after lateral lumbar interbody fusion (LLIF) as a comparative analysis between titanium and polyetheretherketone (PEEK) cages. Many authors describe a reluctance to use titanium cages in spinal fusion secondary to subsidence concerns due to the increased modulus of elasticity of metal cages. The authors intend for this report to provide observational data regarding the juxtaposition of these two materials in the LLIF domain. METHODS: A retrospective review of a prospectively maintained database identified 113 consecutive patients undergoing lateral fusion for degenerative indications from January to December 2017. The surgeons performing the cage implantations were two orthopedic spine surgeons and two neurosurgeons. Plain standing radiographs were obtained at 1-2 weeks, 8-12 weeks, and 12 months postoperatively. Using a validated grading system, interbody subsidence into the endplates was graded at these time points on a scale of 0 to III. The primary outcome measure was subsidence between the two groups. Secondary outcomes were analyzed as well. RESULTS: Of the 113 patients in the sample, groups receiving PEEK and titanium implants were closely matched at 57 and 56 patients, respectively. Cumulatively, 156 cages were inserted and recombinant human bone morphogenetic protein-2 (rhBMP-2) was used in 38.1%. The average patient age was 60.4 years and average follow-up was 75.1 weeks. Subsidence in the titanium group in this study was less common than in the PEEK cage group. At early follow-up, groups had similar subsidence outcomes. Statistical significance was reached at the 8- to 12-week and 52-week follow-ups, demonstrating more subsidence in the PEEK cage group than the titanium cage group. rhBMP-2 usage was also highly correlated with higher subsidence rates at all 3 follow-up time points. Age was correlated with higher subsidence rates in univariate and multivariate analysis. CONCLUSIONS: Titanium cages were associated with lower subsidence rates than PEEK cages in this investigation. Usage of rhBMP-2 was also robustly associated with higher endplate subsidence. Each additional year of age correlated with an increased subsidence risk. Subsidence in LLIF is likely a response to a myriad of factors that include but are certainly not limited to cage material. Hence, the avoidance of titanium interbody implants secondary solely to concerns over a modulus of elasticity likely overlooks other variables of equal or greater importance.

Comparison of two reinforcement rings for primary total hip arthroplasty addressing displaced acetabular fractures: a biomechanical analysis.

INTRODUCTION: Aim of this study was to biomechanically compare two different acetabular cup fixation constructs in terms of fracture fixation for displaced acetabular fractures involving the anterior column with hemitransverse fracture under partial and full weight-bearing conditions. METHODS: Two different reinforcement rings designed as cages for primary THA were biomechanically tested in terms of managing a complex acetabular fracture. Single-leg stance cyclic loading was performed to assess fracture gap movement and fragment rotation. Twelve hemi pelvis Sawbones were divided into two groups: primary THA with acetabulum roof reinforcement plate (ARRP) (n = 6) and primary THA with Burch-Schneider reinforcement cage (BSRC) (n = 6). RESULTS: During loading under partial weight-bearing (250 N) fracture gap movement tended to be larger in the BSRC group as compared to the ARRP group. Under full weight-bearing conditions, the ARRP showed 60% significantly less motion (p = 0.035) of the os ilium to os ischii gap compared to BSRC. Fracture gap movements between the os ilium and spina iliaca fragments were significantly reduced by 76% (p = 0.048) for ARRP in contrast to BSRC. The ARRP group also demonstrated significantly less movement in the fracture gaps os ischii to quadrilateral plate (62% reduction, p = 0.009) and quadrilateral plate to spina iliaca (87% reduction, p < 0.001). Significantly less rotational movement of the quadrilateral plate to the os ilium was exhibited by the ARRP group (p = 0.015). CONCLUSIONS: The presented acetabulum roof-reinforcement plate (ARRP) provides stable conditions at the acetabular component with adequate stabilization of a displaced acetabular fracture.

The Anterior Subcutaneous Pelvic Ring Fixator: No Biomechanical Advantages Compared with External Fixation.

BACKGROUND: Subcutaneous fixation of the anterior pelvic ring is an emerging surgical technique for trauma patients. The aim of this study was to biomechanically evaluate 2 internal fixation devices for stabilizing a disrupted pelvic ring and compare them with traditional external fixation. METHODS: Thirty-six synthetic pelvises with a simulated unstable ring fracture (anteroposterior compression type III) were divided into 3 groups. Group A underwent fixation with a supra-acetabular external fixator; group B, with an internal fixator using the USS II polyaxial system; and group C, with an internal fixator using the Click'X polyaxial system. Biomechanical testing included measurement of peak-to-peak displacement at 300, 400, and 500 N; total displacement; plastic deformation; stiffness; and fracture-line displacement. RESULTS: Statistical analysis of all measured parameters revealed no significant differences among the groups. However, vertical displacement of the preshaped connecting rod within the screw heads occurred as a result of inadequate stability of the internal fixation at the rod-screw interface. CONCLUSIONS: Although internal fixator devices are placed close to the bone and should therefore maintain greater stiffness, our data did not support the hypothesis of superior stability. Special attention is required when using a curved connecting rod as the rod is easily displaced, placing relevant anatomical structures at risk. These devices require further refinement to avoid potential patient injury.

Comparison of internal fixation with Gamma3 Long nails and INTERTAN nails in the treatment of Seinsheimer type V subtrochanteric femoral fractures in elderly patients.

The aim of this study was to clinically compare the therapeutic effects of internal fixation using a third-generation Gamma Long Nail (TGLN) with that of INTERTAN in the treatment of Seinsheimer Type V subtrochanteric femoral fractures in elderly patients.The therapeutic effect of internal fixation with TGLN, compared with that with INTERTAN, was retrospectively analyzed in elderly patients diagnosed with Seinsheimer Type V subtrochanteric fracture. Twenty-five cases were divided into 2 groups based on the fixation devices: the TGLN group (13 cases; 5 men and 8 women) and the INTERTAN group (12 cases; 5 men and 7 women). Patients were followed up postoperatively, and their clinical history, intraoperative blood loss, fracture healing, Harris Hip Scores, and postoperative complications were recorded and compared.Patients in the TGLN group had shorter operation time and less intraoperative blood loss, compared with those in the INTERTAN group (P < .05). There were no significant between-group differences in postoperative complications, fracture healing time and Harris Hip Scores during the follow-up (P > .05).

Four-corner fusion: Comparing outcomes of conventional K-wire-, locking plate-, and retrograde headless compression screw fixations.

PURPOSE: Several operative approaches and various implants for osseous fixation have been described to achieve four-corner fusion of the wrist. Given the discordance and to aid in further standardizing the technique, this study directly compares the outcomes of K-wire, fusion plate, and headless retrograde compressive screw fixations to achieve four-corner arthrodesis. METHODS: Sixty-four patients underwent four-corner fusion over a period of 5 years and were reviewed retrospectively. Twenty-one patients underwent bone fixation with conventional K-wires, 26 with locking plates, and 17 patients were treated by headless retrograde compressive screw fixations. Patients of the different groups were comparable regarding age, sex, hand dominance, and stage of disease. RESULTS: All study groups showed significant improvements in grip strength, decrease in pain (NRS) at rest and with activity, range-of-motion of the wrist, and wrist function (measured by the DASH-score). When evaluating the three groups amongst each other, overall complication and nonunion rates were low and revealed no significant differences between the groups of patients. However, regarding postoperative NRS at activity, dorsal flexion, and DASH-scores, the "screw" group showed significantly better results than the "wire" group. CONCLUSION: The results show that all examined techniques of four-corner fusion can improve wrist function when compared to preoperative baseline (NRS at rest and activity, postoperative DASH-scores). However, headless retrograde compressive screw fixation had significant better results regarding pain relief (NRS) at activity and postoperative DASH-scores.

Mechanical performance of traditional distraction-based dual growing rod constructs.

BACKGROUND: Growing rod constructs are an important contribution in the treatment of children with early onset scoliosis even though these devices experience high rates of rod fracture. The mechanical performance of traditional, distraction-based dual growing rod constructs is not well understood, and mechanical models for predicting device performance are limited. PURPOSE: Two mechanical models were developed and used to determine the mechanical performance of various growing rod configurations by increasing construct complexity. STUDY DESIGN/SETTING: Mechanical bench testing and finite element (FE) analysis. METHODS: Static and dynamic compression bending tests were based on an ASTM F1717 method modified to accommodate dual growing rod constructs. Six construct configurations were tested, mechanical properties were recorded, and statistical analyses were performed to determine significant differences between groups: (1) no connectors (rods only), (2) side-by-side connectors, (3) side-by-side connectors plus 4 crosslinks, (4) (40-mm long tandem connectors, (5) 80-mm long tandem connectors, and (6) 80-mm long tandem connectors plus 4 crosslinks. FE analysis was used to predict the stress distribution within the constructs. RESULTS: The static results indicated greater stiffness, yield load, and peak load as the axial connector length increased (side-by-side to 40 mm tandem to 80 mm tandem). The dynamic results showed similar cycles to failure for side-by-side and tandem connector (40 and 80 mm) construct configurations without crosslinks. Crosslinks shifted the location of rod fracture observed experimentally and significantly reduced the fatigue life of the construct. The flexibility of the construct decreased significantly as the axial connector length increased. FE predictions were highly consistent with the experimentally measured values and provided information on stress distribution within the rod for comparison to experimental fracture locations. CONCLUSIONS: This is the first study to evaluate mechanical performance of various configurations of pediatric growing rod constructs using preclinical models. The current study is consistent with a previous retrieval study in that rigid constructs lacking flexibility (ie, higher stiffness and lower displacement), such as those with 80-mm tandem connectors and multiple crosslinks, demonstrated decreased mechanical performance as shown through both experimental and computational models. Additionally, the experimental and computational findings suggest that surgeons should strategically consider the number of interconnecting components and subsequent stress concentrations along the posterior side of the rod. For example, changing the placement of crosslinks to low stress regions of the construct or not using crosslinks in the construct are options.

Lordosis Recreation in Transforaminal and Posterior Lumbar Interbody Fusion: A Cadaveric Study of the Influence of Surgical Bone Resection and Cage Angle.

STUDY DESIGN: Controlled cadaveric study of surgical technique in transforaminal and posterior lumbar interbody fusion (TLIF and PLIF) OBJECTIVE.: To evaluate the contribution of surgical techniques and cage variables in lordosis recreation in posterior interbody fusion (TLIF/PLIF). SUMMARY OF BACKGROUND DATA: The major contributors to lumbar lordosis are the lordotic lower lumbar discs. The pathologies requiring treatment with segmental fusion are frequently hypolordotic or kyphotic. Current posterior based interbody techniques have a poor track record for recreating lordosis, although recreation of lordosis with optimum anatomical alignment is associated with better outcomes and reduced adjacent segment change needing revision. It is unclear whether surgical techniques or cage parameters contribute significantly to lordosis recreation. METHODS: Eight instrumented cadaveric motion segments were evaluated with pre and post experimental radiological assessment of lordosis. Each motion segment was instrumented with pedicle screw fixation to allow segmental stabilization. The surgical procedures were unilateral TLIF with an 18° lordotic and 27 mm length cage, unilateral TLIF (18°, 27 mm) with bilateral facetectomy, unilateral TLIF (18°, 27 mm) with posterior column osteotomy (PCO), PLIF with bilateral cages (18°, 22 mm), and PLIF with bilateral cages (24°, 22 mm). Cage insertion used and "insert and rotate" technique. RESULTS: Pooled results demonstrated a mean increase in lordosis of 2.2° with each procedural step (lordosis increase was serially 1.8°, 3.5°, 1.6°, 2.5°, and 1.6° through the procedures). TLIF and PLIF with PCO increased lordosis significantly compared with unilateral TLIF and TLIF with bilateral facetectomy. The major contributors to lordosis recreation were PCO, and PLIF with paired shorter cages rather than TLIF. CONCLUSION: This study demonstrates that the surgical approach to posterior interbody surgery influences lordosis gain and PCO optimizes lordosis gain in TLIF. The bilateral cages used in PLIF are shorter and associated with further gain in lordosis. This information has the potential to aid surgical planning when attempting to recreate lordosis to optimize outcomes. LEVEL OF EVIDENCE: N/A.

Is unilateral pedicle screw fixation superior than bilateral pedicle screw fixation for lumbar degenerative diseases: a meta-analysis.

BACKGROUND: To investigate whether unilateral pedicle screw fixation is superior than bilateral pedicle screw fixation for lumbar degenerative diseases. METHODS: Electronic databases including PubMed, Embase, and the Cochrane Library up to August 2018 were searched. All the high-quality randomized controlled trials (RCTs) and prospective clinical controlled studies comparing the unilateral pedicle screw fixation and bilateral pedicle screw fixation for lumbar degenerative diseases were enrolled in this study. Fusion rate was the main outcome. Stata 12.0 was used for the meta-analysis. RESULTS: Twelve RCTs including 808 patients (unilateral pedicle screw fixation = 393, bilateral pedicle screw fixation = 415) were included in our meta-analysis. There was a significant difference between unilateral pedicle screw fixation and bilateral pedicle screw fixation in terms of the fusion rate (risk ratio (RR) = 0.96, 95%CI [0.92, 1.00], P = 0.073), visual analog scale (VAS) at final follow-up, Oswestry Disability Index (ODI), Japanese Orthopedic Association scores (JOA), short-form health survey (SF-36), and length of hospital stay. Compared with bilateral pedicle screw fixation, unilateral pedicle screw fixation was associated with a reduction of the total blood loss and operation time (P < 0.05). Unilateral pedicle screw fixation was associated with an increase of the cage migration than bilateral pedicle screw fixation (17.1% vs 7.1%, RR = 2.40, 95% CI = 1.17 to 4.93; P = 0.017). CONCLUSIONS: Unilateral pedicle screw fixation and bilateral pedicle screw fixation has similar fusion rate when treating for lumbar degenerative diseases. Our meta-analysis suggested that compared with bilateral pedicle screw fixation, unilateral pedicle screw fixation significantly reduced total blood loss and operation time for lumbar degenerative diseases. The use of unilateral pedicle screw for lumbar degenerative diseases increases the cage migration.

Anterior cervical discectomy and fusion with stand-alone anchored cages versus posterior laminectomy and fusion for four-level cervical spondylotic myelopathy: a retrospective study with 2-year follow-up.

BACKGROUND: The optimal treatment for multi-level cervical spondylotic myelopathy (CSM) remains controversial. Posterior approach is most commonly used, but complicated with insufficient decompression and postoperative axial neck pain. The anterior approach is effective in neural decompression with less surgical trauma. However, the profile of the plate or the possible construct failure may cause dysphagia after surgery. Recently, anterior cervical discectomy and fusion (ACDF) with self-anchored cage is reported to have a superior result over ACDF with anterior plates and screws in three-level CSM. The purpose of the study is to compare the clinical and radiological outcomes of ACDF using stand-alone anchored cages to that of laminectomy with fusion (LF) for treating four-level CSM. METHODS: Twenty-six patients underwent four-level ACDF (Group A) and 32 patients with four-level LF (Group B) were retrospectively reviewed and followed-up for 24 months. Clinical efficacy was evaluated by comparing pre- and post-operative Japanese Orthopedic Association (JOA) and Neck Disability Index (NDI) scores. Operative time, blood loss, fusion, lordosis change and complications were evaluated. RESULTS: There was significantly less blood loss in Group A (163.4 ± 72.1 ml) than Group B (241.0 ± 112.3 ml) (P < 0.05). Both groups demonstrated significant improvements in JOA and NDI scores after surgery with similar operative time. Improvements in cervical lordosis and fused segment lordosis were more pronounced in Group A (11.3 ± 5.9°, 9.7 ± 5.3°) than Group B (5.8 ± 4.6°, 5.5 ± 4.5°) (P < 0.05). Loss of lordosis in the cervical spine and fused segment was more prominent in Group A (11.7 ± 2.2°, 6.7 ± 3.2°) than Group B (7.5 ± 3.8°, 3.7 ± 3.4°) (P < 0.05) at the final follow-up. Complication rate in Group A and Group B was 57.69 and 18.75%, respectively. CONCLUSIONS: ACDF using a stand-alone anchored cage showed similar clinical results to LF for the treatment of four-level CSM, with better lordosis correction and less blood loss. However, ACDF was associated with more loss of lordosis after surgery and more non-unions.

Efficacy of internal fixation with mini plate and internal fixation with hollow screw for Regan-Morrey type II and III ulna coronoid fractures.

BACKGROUND: Ulna coronoid fracture is a complicated injury and occurred in the coronal plane. Undeniably, there is no universally accepted approach for treating ulna coronoid fractures. Therefore, this study aimed at exploring the efficacy of different surgical treatments for Regan-Morrey type II and III ulna coronoid fractures. METHODS: A total of 164 patients with ulna coronoid fractures were admitted and treated in department of orthopedics at Yiwu Central Hospital, the Affiliated Yiwu Hospital of Wenzhou Medical University for retrospective analysis. The baseline features (age, gender, time from injury to surgery and so on) before the surgery and different conditions during the surgery were compared. Following that, the Visual Analogue Scale (VAS) pain score was employed to evaluate the severity of preoperative and postoperative pain experienced by the patients in each group. Afterwards, Broberg and Morrey elbow score was used to evaluate elbow joint function and surgical effect of the patients. Lastly, the postoperative recovery and complications were compared. RESULTS: It was firstly observed that internal fixation with mini plate and hollow screw compelled to lower average operation time and blood loss than Kirschner wire and steel wire suture. Next, the severity of postoperative pain was lessened in comparison with preoperative pain. Afterwards, mini plate and hollow screw improved elbow joint function more notable than Kirschner wire and steel wire suture, and Kirschner wire and steel wire suture resulted in higher incidence of complications and worse postoperative recovery. CONCLUSION: Collectively, this study clarified that for the treatment of Regan-Morrey type II and III ulna coronoid fractures, internal fixation with mini plate and hollow screw has an overall superior surgical effect than internal fixation with Kirschner wire and steel wire suture.

A CARE-compliant article: Biomechanics of treating early-stage femoral-head osteonecrosis by using a ß-tricalcium phosphate bioceramic rod system: a 3-dimensional finite-element analysis.

The effect of implanting a ß-TCP bioceramic rod system (BRS) can be observed with using the 3-dimensional (3D) finite-element method on the biomechanics of early-stage osteonecrosis of the femoral head (ONFH), to provide a theoretical basis for the biomechanics of applying the ß-TCP BRS in the treatment of ONFH.A healthy 172 cm tall male adult volunteer (age: 40 years, weight: 70 kg, and femoral diameter: 50 mm) was selected for this study. The volunteer had no history of diseases in the hip, lower back, and lower limbs. He also had no history of trauma and surgery and had no lesions in the femoral head.A finite-element model of the normal proximal femur was constructed, and on this basis, 4 ONFH finite-element models were constructed, which had 15% and 30% necrotic areas in the superolateral area and 2 and 4 mm collapse in the weight-bearing area of the femoral head, respectively.This process was followed by simulated implantation of the ß-TCP BRS in the finite-element models of the femoral head. Changes in the stress and displacement of the femoral head were observed before and after treatment with the ß-TCP BRS, and the risk of femoral-head collapse was assessed.Under an applied walking load, the stress concentration on the femoral head was alleviated after treatment. Moreover, the stress and collapse values of the weight-bearing area decreased compared with those before treatment, and the differences were statistically significant (P < .05); the risk of collapse was also lower than that before treatment. As the area of the necrosis increased, the collapse value also increased, and the risk of collapse increased. More severe preoperative collapse implied that a greater risk of postoperative recollapse exists.This case report was written for 4 purposes: Implantation of the ß-TCP BRS could effectively improve the internal mechanical properties of ONFH, enhance the support capacity of bones in the weight-bearing area in ONFH, reduce the compressive stress on the necrotic bone, and lower the risk of collapse in ONFH.

A retrospective comparative study of arthroscopic fixation in acute Rockwood type IV acromioclavicular joint dislocation: single versus double paired Endobutton technique.

BACKGROUND: Rockwood type IV acromioclavicular joint (ACJ) dislocation is a trauma usually needs surgical treatment. Paired EndoButton technique (PET) is used in treating such condition. However, the effect of using different types of PET (single versus double PET) for fixation remains controversial. This study aims to evaluate and compare the efficacy of single and double PET and to provide a suitable option for the surgeons. METHODS: We retrospectively reviewed the charts of patients with acute Rockwood type IV ACJ dislocation who had undergone arthroscopic fixation using single or double PET fixation between March 2009 and March 2015. Seventy-eight consecutive patients identified from chart review were picked and were divided into the single and double PET group with 39 cases in each group. The indexes of visual analog scale score (VAS) for pain, the radiographs of the affected shoulder at different time points of the follow-up, the time of return to activities and sports, the constant functional score, and the Karlsson acromioclavicular joint (ACJ) score, were assessed in a minimum of 2 years postoperation. RESULTS: The average coracoclavicular (CC) and acromioclavicular (AC) distances of the affected joints in the double PET group were significantly smaller than those of the single PET group 2 years postoperation (P < 0.05). The average AC and CC distances in the healthy shoulder joints were significantly smaller than those of the affected joints in the single PET group (P < 0.05); however, these values were not significantly different from those of the affected joints in the double PET group (P > 0.05). The mean VAS pain score was not significantly different, while significant difference was found for the number and times of cases return to activities and sports, constant functional score, and Karlsson ACJ score (P < 0.05) between the two groups. Therefore, the double PET group has better outcome than the single PET group. Complications including redislocation, button slippage, erosion, or AC joint instability occurred in the single PET group, while the complication in the double PET group was rare. CONCLUSIONS: Compared with the single PET, the double PET group achieved better outcome with less complications in arthroscopically treating acute Rockwood type IV ACJ dislocation.

A comparison of zero-profile anchored spacer (ROI-C) and plate fixation in 2-level noncontiguous anterior cervical discectomy and fusion- a retrospective study.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) is the classic surgical treatment for symptomatic cervical degenerative disc disease (CDDD). However, there is controversy over the best surgical management in patients with two noncontiguous symptomatic levels of CDDD. METHODS: From April 2011 to May 2014, 44 patients with two noncontiguous symptomatic levels of CDDD underwent skip-level ACDFs. In Group NoPlate, 23 cases underwent 2 noncontiguous levels of ACDF using zero-profile anchored spacer; and in Group Plate, 21 cases underwent 2 noncontiguous levels of ACDF using cages and plates. Operation-related paraeters for each group were recorded and compared. Japanese Orthopedic Association (JOA) scores and Neck Disability Index (NDI) scores at preoperation and postoperation were compared with at least a 2-year follow-up. Cervical lordosis was analyzed before surgery, 1 month after surgery, 3 months after surgery, and at final follow-up. RESULTS: Mean follow-up was 35.4 ± 6.5 (range 24-48) months. Significant improvement on the JOA, NDI scores and cervical lordosis was noted in each group (p < 0.05), and there were no significant difference in terms of JOA, NDI scores, cervical lordosis and fusion rate between the two groups (P > 0.05). The operation time in Group NoPlate was significantly shorter than in Group Plate (p < 0.05), and the incidence of dysphagia and adjacent segment degeneration in Group NoPlate was significantly lower than in Group Plate (p < 0.05). CONCLUSIONS: ROI-C and cages with plate fixation were both effective in two-level noncontiguous ACDF, and there were no significant difference in clinical outcomes, fusion rate, and cervical lordosis. However, ROI-C was associated with shorter operative time, lower incidence of dysphagia and adjacent segment degeneration.

Biomechanical Analysis of Lateral Lumbar Interbody Fusion Constructs with Various Fixation Options: Based on a Validated Finite Element Model.

BACKGROUND: Lateral lumbar interbody fusion using cage supplemented with fixation has been used widely in the treatment of lumbar disease. A combined fixation (CF) of lateral plate and spinous process plate may provide multiplanar stability similar to that of bilateral pedicle screws (BPS) and may reduce morbidity. The biomechanical influence of the CF on cage subsidence and facet joint stress has not been well described. The aim of this study was to compare biomechanics of various fixation options and to verify biomechanical effects of the CF. METHODS: The surgical finite element models with various fixation options were constructed based on computed tomography images. The lateral plate and posterior spinous process plate were applied (CF). The 6 motion modes were simulated. Range of motion (ROM), cage stress, endplate stress, and facet joint stress were compared. RESULTS: For the CF model, ROM, cage stress, and endplate stress were the minimum in almost all motion modes. Compared with BPS, the CF reduced ROM, cage stress, and endplate stress in all motion modes. The ROM was reduced by more than 10% in all motion modes except for flexion; cage stress and endplate stress were reduced more than 10% in all motion modes except for rotation-left. After interbody fusion, facet joint stress was reduced substantially compared with the intact conditions in all motion modes except for flexion. CONCLUSIONS: The combined plate fixation may offer an alternative to BPS fixation in lateral lumbar interbody fusion.