Strategy for obtaining solid fusion at L5-S1 in adult spinal deformity: risk factor analysis for nonunion at L5-S1.

OBJECTIVE: Maintaining lumbosacral (LS) arthrodesis and global sagittal balance after long fusion to the sacrum remains an important issue in the surgical treatment for adult spinal deformity (ASD). The importance and usefulness of LS fixation have been documented, but the optimal surgical long fusion to the sacrum remains a matter for debate. Therefore, the authors performed a retrospective study to evaluate fusion on CT scans and the risk factors for LS pseudarthrosis (nonunion) after long fusion to the sacrum in ASD. METHODS: The authors performed a retrospective study of 59 patients with lumbar degenerative kyphosis (mean age 69.6 years) who underwent surgical correction, including an interbody fusion of the L5-S1, with a minimum 2-year follow-up. Achievement of LS fusion was evaluated by analyzing 3D-CT scans at 3 months, 6 months, 9 months, 1 year, and 2 years after surgery. Patients were classified into a union group (n = 36) and nonunion group (n = 23). Risk factors for nonunion were analyzed, including patient and surgical factors. RESULTS: The overall fusion rate was 61% (36/59). Regarding radiological factors, optimal sagittal balance at the final follow-up significantly differed between two groups. There were no significant differences in terms of patient factors, and no significant differences with respect to the use of pedicle subtraction osteotomy, the number of fused segments, the proportion of anterior versus posterior interbody fusion, S2 alar iliac fixation versus conventional iliac fixation, or loosening of sacral or iliac screws. However, the proportion of metal cages to polyetheretherketone cages and the proportion of sacropelvic fixation were significantly higher in the union group (p = 0.022 and p < 0.05, respectively). CONCLUSIONS: LS junction fusion is crucial for global sagittal balance, and the use of iliac screws in addition to LS interbody fusion using a metal cage improves the outcomes of long fusion surgery for ASD patients.

Minimally invasive multilevel lateral lumbar interbody fusion with posterior column osteotomy compared with pedicle subtraction osteotomy for adult spinal deformity.

BACKGROUND CONTEXT: Pedicle subtraction osteotomy (PSO) is highly effective as a sagittal correction approach in patients with adult spinal deformity, but relevant issues such as surgical complexity and long-term complications limit its applicability. Recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity; however, few reports have directly compared these techniques with PSO. PURPOSE: The purpose of this study was to evaluate the radiological and clinical efficacies of oblique lateral interbody fusion (OLIF) with posterior column osteotomy (PCO) using stiff rods (6.35-mm cobalt chrome [CoCr]). STUDY DESIGN: Retrospective comparative study. PATIENT SAMPLE: One-hundred six patients (average age 71.3 years) diagnosed with adult spinal deformity presenting with sagittal imbalance for whom follow-up of over 2 years after sagittal correction (between 2013 and 2017) was available. OUTCOME MEASURES: Description and analysis of X-ray, computed tomography scans, operative time, estimated blood loss, and clinical outcomes (Oswestry Disability Index [ODI] and Visual Analog Scale [VAS]). METHODS: A comparative analysis was performed evaluating spinopelvic parameters and clinical outcomes including the ODI, VAS, and complications in patients who underwent PSO (PSO group; n=65) or multilevel prepsoas OLIF combined with PCO and open posterior spinal fusion using 6.35-mm CoCr rods (OLIF group; n=41). The authors have no conflicts of interest to disclose. RESULTS: There were no differences in preoperative spinopelvic parameters between the PSO and OLIF groups. Although no differences were observed between the two groups in terms of postoperative SVA (-12.66 mm vs. -16.44 mm), postoperative lumbar lordosis (-71.46° vs. -72.55°), lumbar lordosis correction (77.96° vs. 73.54°), or postoperative pelvic tilt (9.35° vs. 7.17°), the estimated blood loss was significantly lower in the OLIF group (2824 mL vs. 1736 mL, p<.05). No differences were observed in clinical outcomes (ODI, VAS, and clinical complications), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after surgery. However, pseudarthrosis during the follow-up period, including rod fracture, occurred less frequently in the OLIF group compared with that in the PSO group (p<.05). OLIF was performed from the T12-L1 to L5-S1 regions (124 segments), with an average of three segments per patient. The computed tomography scans immediately after surgery showed an average segmental correction of -18° and 12.9% (16 segments) of 124 segments showed a correction angle of >30°. CONCLUSIONS: Multilevel OLIF with PCO using a stiff rod to treat severe sagittal imbalance resulted in similar levels of sagittal balance and lordosis correction as obtained by PSO. Multilevel OLIF with PCO using a stiff rod can be an effective alternative to PSO for patients with severe sagittal imbalance.

Preliminary report on the flexible rod technique for prevention of proximal junctional kyphosis following long-segment fusion to the sacrum in adult spinal deformity.

OBJECTIVE: The incidence of proximal junctional kyphosis (PJK) after long-segment fixation in patients with adult spinal deformity (ASD) has been reported to range from 17% to 61.7%. Recent studies have reported using "hybrid" techniques in which semirigid fixation is introduced between the fused and flexible segments at the proximal level to allow a more gradual transition. The authors used these hybrid techniques in a clinical setting and analyzed PJK to evaluate the usefulness of the flexible rod (FR) technique. METHODS: The authors retrospectively selected 77 patients with lumbar degenerative kyphosis (LDK) who underwent sagittal correction and long-segment fixation and had follow-up for > 1 year. An FR was used in 30 of the 77 patients. PJK development and spinal sagittal changes were analyzed in the FR and non-FR groups, and the predictive factors of PJK between a PJK group and a non-PJK group were compared. RESULTS: The patient population comprised 77 patients (75 females and 2 males) with a mean (± SD) follow-up of 32.0 ± 12.7 months (36.7 ± 9.8 months in the non-FR group and 16.8 ± 4.7 months in the FR group) and mean (± SD) age of 71.7 ± 5.1 years. Sagittal balance was well maintained at final follow-up (10.5 and 1.5 mm) in the non-FR and FR groups, respectively. Thoracic kyphosis (TK) and lumbar lordosis (LL) were improved in both groups, without significant differences between the two (p > 0.05). PJK occurred in 28 cases (36.4%) in total, 3 (10%) in the FR and 25 (53.2%) in the non-FR group (p < 0.001). Postoperatively, PJK was observed at an average of 8.9 months in the non-FR group and 1 month in the FR group. No significant differences in the incidence of PJK regarding patient factors or radiological parameters were found between the PJK group and non-PJK group (p > 0.05). However, FR (vs non-FR) and interbody fusion except L5-S1 using oblique lumbar interbody fusion (vs non-oblique lumbar interbody fusion), demonstrated a significantly lower PJK prevalence (p < 0.001 and p = 0.044) among the surgical factors. CONCLUSIONS: PJK was reduced after surgical treatment with the FR in the patients with LDK. Solid long-segment fixation and the use of the FR may become another surgical option for spine surgeons who plan and make decisions regarding spine reconstruction surgery for patients with ASD.

Novel Antibiotic-Loaded Cement Femoral Head Spacer for the Treatment of Advanced Pyogenic Arthritis in Adult Hip.

BACKGROUND: The aim of this study is to present a treatment for end-stage pyogenic arthritis of the hip using a novel cement spacer. This spacer caused less damage to the proximal femoral bone and made the conversion to total hip arthroplasty (THA) more convenient while maintaining the advantages of current cement spacers loaded with antibiotics. METHODS: We retrospectively reviewed 10 consecutive cases of hip pyogenic arthritis with joint destruction. These cases occurred from September 2009 to June 2015. In these cases, we used an antibiotic-loaded, cement spacer that was formed in the shape of the femoral head. This spacer rested on multiple screws that were inserted in the remaining neck of the femur. Once the infection subsided, a conversion to THA was performed in all cases. Evaluation included clinical and radiologic outcomes and the development of complications. RESULTS: The mean interval between spacer insertion and conversion to THA was 101.6 days (range, 59-187 days). The mean follow-up period from initial spacer insertion was 44.9 months (range, 15-95 months). All cases underwent noncemented THA following the resolution of the initial infection. The mean Harris Hip Scores at initial visit, before conversion to THA, and on final follow-up were 58.8, 71.0, and 92.5, respectively. No case had any spacer-related complications, recurrence of infection, or dislocation. CONCLUSION: The treatment of advanced pyogenic arthritis with this novel femoral head spacer technique significantly reduced pain, preserved proximal femoral bone and soft tissue tension, controlled infection, improved function, and allowed for easier conversion to THA.

Comparison of continuous infusion versus bolus injection of factor concentrates for blood management after total knee arthroplasty in patients with hemophilia.

BACKGROUND: Total knee arthroplasty (TKA) has become the treatment of choice for end-stage hemophilic arthropathy of the knee. Theoretically in hemophilia A, perioperative continuous infusion (CI) of factor VIII (FVIII) would provide a more consistent FVIII level than general bolus injections (BI) in TKA. Current study was designed to evaluate the effectiveness of CI of coagulation factor concentrates during the perioperative period compared to BI. METHODS: A total of 42 TKAs were performed in 31 patients with severe hemophilia A. Under the supervision of a multidisciplinary hemophilia team, CI and BI were monitored during application of a standardized regimen. Perioperative clinical parameters including postoperative hemoglobin drop, drained blood volume, transfusion rate, total consumption of FVIII, and perioperative complications were assessed. RESULTS: The difference in the postoperative hemoglobin drop was significant between two groups with a lower decrease in the CI group (p = 0.002). The drained blood volume for postoperative 24 h was significantly lower in the CI than the BI groups (p = 0.037). Total consumption of factor concentrates for postoperative 5 days was greater in the CI group than in the BI group (p = 0.000). One postoperative hematoma and wound dehiscence occurred in BI group and no other complication developed. CONCLUSIONS: Although good control of hemostasis could be achieved using either method during the perioperative period of TKA, CI seems more tolerable and effective than BI to provide perioperative blood management undergoing TKA in patients with hemophilia. TRIAL REGISTRATION: The study was retrospectively registered in WHO ICTRP under identifier KCT0002404 (date of registration: August 04, 2017).

How does back muscle strength change after posterior lumbar interbody fusion?

OBJECTIVE There is a lack of evidence of how back muscle strength changes after lumbar fusion surgery and how exercise influences these changes. The aim of this study was to evaluate changes in back muscle strength after posterior lumbar interbody fusion (PLIF) and to measure the effects of a postoperative exercise program on muscle strength and physical and mental health outcomes. METHODS This prospective study enrolled 59 women (mean age 58 years) who underwent PLIF at 1 or 2 spinal levels. To assess the effects of a supervised lumbar stabilization exercise (LSE), the authors allocated the patients to an LSE (n = 26) or a control (n = 33) group. The patients in the LSE group performed the LSEs between 3 and 6 months postoperatively. Back extensor strength, visual analog scale (VAS) scores in back pain, and physical component summary (PCS) and mental component summary (MCS) scores on the 36-Item Short Form Health Survey were determined for the both groups. RESULTS Mean strength of the back muscles tended to slightly decrease by 7.5% from preoperatively to 3 months after PLIF (p = 0.145), but it significantly increased thereafter and was sustained until the last follow-up (38.1%, p < 0.001). The mean back muscle strength was similar in the LSE and control groups preoperatively, but it increased significantly more in the LSE group (64.2%) than in the control group (21.7%) at the last follow-up 12 months after PLIF (p = 0.012). At the last follow-up, decreases in back pain VAS scores were more significant among LSE group patients, who had a pain reduction on average of 58.2%, than among control group patients (reduction of 26.1%) (p = 0.013). The patients in the LSE group also had greater improvement in both PCS (39.9% improvement) and MCS (20.7% improvement) scores than the patients in the control group (improvement of 18.0% and 1.1%, p = 0.042 and p = 0.035, respectively). CONCLUSIONS After PLIF, strength in back muscles decreased until 3 months postoperatively but significantly increased after that period. The patients who regularly underwent postoperative LSE had significantly improved back strength, less pain, and less functional disability at 12 months postoperatively.

Amyloid Arthropathy of the Hip Joint Associated with Multiple Myeloma: A Case Report.

Amyloidosis is a disease characterized by the deposition of non-soluble fibrous protein in multiple tissues with a number of possible causes. This protein deposition can occur in any tissue, yet is most commonly seen in kidneys, heart, and gastrointestinal tracts. However, invasion to bone tissues is not often reported. The deposition of amyloid proteins in bone tissues may result in joint pain and pathological fractures; it is important to elucidate the causes and detect early to determine prognosis and treat optimally. In the present case report, with relevant literature review, the authors report a case of total hip arthroplasty in an amyloidosis patient.

The Relationship between the Progression of Kyphosis in Stable Thoracolumbar Fractures and Magnetic Resonance Imaging Findings.

STUDY DESIGN: Retrospective study. PURPOSE: To investigate the relation between the progression of kyphotic deformity and magnetic resonance imaging (MRI) findings in conservatively treated stable thoracolumbar fractures. OVERVIEW OF LITERATURE: When treated conservatively, excessive progression of kyphotic deformity and vertebral compression can emerge during follow-up. We sought to identify predictors of vertebral body deformation using MR images. METHODS: The presence in MR images of anterior longitudinal ligament (AL) or posterior longitudinal ligament (PL) injury, superior or inferior endplate disruption, superior or inferior disc injury in fractured vertebral bodies, the existence of low signal intensity on T2 weighted images, and bone edema of intravertebral bodies were assessed. RESULTS: The presence of superior endplate disruption and a higher level of bone edema were found to cause the progressions of kyphotic angle (KA), wedge angle (WA), and anterior vertebral compression (AVC) rate. When AL or superior disc injury was observed, only KA increased meaningfully. When low signal intensity was present on T2 weighted images WA and AVC increased significantly, but PL injury, inferior endplate disruption, and inferior disc injury showed no notable correlation with kyphotic deformity progression. The risk factors found to be associated with an increase of KA to >5° were AL injury, superior endplate disruption, superior disc injury, and a bone edema level of over 1/3, and their associated risks versus no injury cases were 14.1, 3.7, 6.8, and 10.4-fold, respectively. CONCLUSIONS: AL injury, superior endplate and disc injury, or a high level of bone edema, were critical factors that determine kyphotic deformity progression.