Comparison of laminoplasty and posterior fusion surgery for cervical ossification of posterior longitudinal ligament

This prospective multicenter study, established by the Japanese Ministry of Health, Labour and Welfare and involving 27 institutions, aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL), in order to address the controversy surrounding the role of instrumented fusion in cases of posterior surgical decompression for OPLL. 478 patients were considered for participation in the study; from among them, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, there were no significant differences among the participants in terms of patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments. The overall risk of perioperative complications was found to be lower with LM (odds ratio [OR] 0.40, p = 0.006), and the rate of C5 palsy occurrence was significantly lower with LM (OR 0.11, p = 0.0002) than with PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients who had PF was significantly smaller than in those who had LM. However, multivariable logistic regression analysis showed no significant difference among the participants in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in the LM group than in the PF group (OR 2.73, p = 0.0002). Both LM and PF for cervical myelopathy due to OPLL had resulted in comparable postoperative outcomes at 2 years after surgery.

Recurrent ossification of the posterior longitudinal ligament in the upper thoracic region 10 years after initial decompression

Background: Posterior decompression surgery consisting of laminoplasty is generally considered be the treatment of choice for upper thoracic OPLL. Here, we describe a patient who, 10 years following a C3–T4 level laminectomy, developed recurrent OPLL at the T2–3 level with kyphosis requiring a posterior fusion. Case Description: A 64-year-old male with CT documented OPLL at the C3–4, C6–7, and T1–4 levels, originally underwent a cervicothoracic laminectomy with good results. However, 10 years later, when T2–3 OPLL recurred along with kyphosis, he warranted an additional posterior fusion. Conclusion: Due to the long-term risks of developing kyphotic deformity/instability, more patients undergoing initial decompressive surgery alone for upper thoracic OPLL should be considered for primary fusions.

Complications of Posterior Fusion for Atlantoaxial Instability in Children With Down Syndrome

Objective: To clarify the complications of posterior fusion for atlantoaxial instability (AAI) in children with Down syndrome and to discuss the significance of surgical intervention.Methods: Twenty pediatric patients with Down syndrome underwent posterior fusion for AAI between February 2000 and September 2018 (age, 6.1 ± 1.9 years). C1–2 or C1–3 fusion and occipitocervical fusion were performed in 14 and 6 patients, respectively. The past medical history, operation time, estimated blood loss (EBL), duration of Halo vest immobilization, postoperative follow-up period, and intra- and perioperative complications were examined.Results: The operation time was 257.9 ± 55.6 minutes, and the EBL was 101.6 ± 77.9 mL. Complications related to the operation occurred in 6 patients (30.0%). They included 1 major complication (5.0%): hydrocephalus at 3 months postoperatively, possibly related to an intraoperative dural tear. Other surgery-related complications included 3 cases of superficial infections, 1 case of bone graft donor site deep infection, 1 case of C2 pedicle fracture, 1 case of Halo ring dislocation, 1 case of pseudoarthrosis that required revision surgery, and 1 case of temporary neurological deficit after Halo removal at 2 months postoperatively. Complications unrelated to the operation included 2 cases of respiratory infections and 1 case of implant loosening due to a fall at 9 months postoperatively.Conclusion: The complication rate of upper cervical fusion in patients with Down syndrome remained high; however, major complications decreased substantially. Improved intra- and perioperative management facilitates successful surgical intervention for upper cervical instability in pediatric patients with Down syndrome.

Assessment of L5–S1 anterior lumbar interbody fusion stability in the setting of lengthening posterior instrumentation constructs: a cadaveric biomechanical study

OBJECTIVE Excessive stress and motion at the L5–S1 level can lead to degenerative changes, especially in patients with posterior instrumentation suprajacent to L5. Attention has turned to utilization of L5–S1 anterior lumbar interbody fusion (ALIF) to stabilize the lumbosacral junction. However, questions remain regarding the effectiveness of stand-alone ALIF in the setting of prior posterior instrumented fusions terminating at L5. The purpose of this study was to assess the biomechanical stability of an L5–S1 ALIF with increasing lengths of posterior thoracolumbar constructs. METHODS Seven human cadaveric spines (T9–sacrum) were instrumented with pedicle screws from T10 to L5 and mounted to a 6 degrees-of-freedom robot. Posterior fusion construct lengths (T10–L5, T12–L5, L2–5, and L4–5) were instrumented to each specimen, and torque-fusion level relationships were determined for each construct in flexion-extension, axial rotation, and lateral bending. A stand-alone L5–S1 ALIF was then instrumented, and L5–S1 motion was measured as increasing pure moments (2 to 12 Nm) were applied. Motion reduction was calculated by comparing L5–S1 motion across the ALIF and non-ALIF states. RESULTS The average motion at L5–S1 in axial rotation, flexion-extension, and lateral bending was assessed for each fusion construct with and without ALIF. After adding ALIF to a posterior fusion, L5–S1 motion was significantly reduced relative to the non-ALIF state in all but one fused surgical condition (p < 0.05). Longer fusions with ALIF produced larger L5–S1 motions, and in some cases resulted in motions higher than native state motion. CONCLUSIONS Posterior fusion constructs up to L4–5 could be appropriately stabilized by a stand-alone L5–S1 ALIF when using a nominal threshold of 80% reduction in native motion as a potential positive indicator of fusion. The results of this study allow conclusions to be drawn from a biomechanical standpoint; however, the clinical implications of these data are not well defined. These findings, when taken in appropriate clinical context, can be used to better guide clinicians seeking to treat L5–S1 pathology in patients with prior posterior thoracolumbar constructs.

Anterior versus posterior fusion surgery in idiopathic scoliosis: a comparison of health-related quality of life and radiographic outcomes in Lenke 5C curves - results from the Swedish spine registry

Purpose To compare health-related quality of life and radiographic outcomes in patients treated with either anterior or posterior fusion surgery for Lenke 5C type idiopathic scoliosis. Methods We used data from the Swedish spine registry and identified 59 patients with idiopathic scoliosis treated with fusion for Lenke 5C type curves; 27 patients underwent anterior surgery and 32 underwent posterior surgery. All patients had pre- and postoperative radiographic data and postoperative clinical data at a minimum of two years after surgery. Patient-reported outcomes measures included the Scoliosis Research Society (SRS)-22r, EuroQoL 5 dimensions 3 levels (EQ-5D-3L), EQ-visual analogue scale (VAS) and VAS for back pain. Radiographic assessment included measurement of the angle of the major curve, disc angulation below the lowest instrumented vertebra, curve flexibility, rate of curve correction, differences in sagittal parameters, number of fused vertebrae and length of fusion. Results The mean age at surgery was 16 years in both groups. The mean follow-up time was 3.8 years. There were no significant differences in the SRS-22r score and EQ-5D-3L index at follow-up (all p ≥ 0.2). Postoperatively, both the anterior and posterior fusion group demonstrated a significant correction of the major curve (p ≤ 0.001) with no significant difference of the correction rate between the groups (p = 0.4). The posterior fusion group had shorter operative time (p < 0.001) and higher perioperative blood loss (p = 0.004) while the anterior group had lower number of fused vertebrae ( p< 0.001). Conclusion The type of surgical approach for Lenke 5C curves is not associated with differences in health-related quality of life, despite the lower number of fused vertebrae after anterior surgery. Level of Evidence III

Preoperative pelvic obliquity: possible relation to postoperative coronal decompensation in thoracolumbar/lumbar adolescent idiopathic scoliosis

OBJECTIVE Pelvic obliquity is frequently observed in patients with adolescent idiopathic scoliosis with thoracolumbar/lumbar (TL/L) curve. This study aimed to assess pelvic obliquity changes and their effects on clinical outcomes of posterior fusion surgery. METHODS Data in 80 patients (69 with type 5C and 11 with type 6C adolescent idiopathic scoliosis) who underwent posterior fusion surgery were retrospectively analyzed. Pelvic obliquity was defined as an absolute pelvic obliquity angle (POA) value of ≥ 3°. The patients were divided into groups according to preoperative pelvic obliquity. Moreover, patients with preoperative pelvic obliquity were divided based on POA change from preoperative values versus 2 years postoperatively. Patients were divided based on the presence of selective or nonselective TL/L fusion. Radiographic parameters and clinical outcomes were compared between these groups. RESULTS Among 80 patients, 41 (51%) showed preoperative pelvic obliquity, and its direction was upward to the right for all cases. Coronal decompensation 2 years postoperatively was significantly elevated in patients with preoperative pelvic obliquity (p < 0.05). Thirty-two patients (40%) displayed pelvic obliquity 2 years postoperatively. Among 41 patients with preoperative pelvic obliquity, 22 patients (54%) were in the group with a decrease in POA, and 19 were in the group with no decrease. The group with no decrease in POA showed significant TL/L curve progression throughout the postoperative follow-up period. The patients with nonselective fusion showed a significantly lower incidence of pelvic obliquity at 2 years postoperatively. CONCLUSIONS Postoperative coronal decompensation more frequently occurred in patients with preoperative pelvic obliquity than in those without pelvic obliquity preoperatively. In addition, postoperative pelvic obliquity changes may be related to residual lumbar curve behavior.