The effect of cement augmentation on pedicle screw fixation under various load cases : results from a combined experimental, micro-CT, and micro-finite element analysis.

Aims: Anchorage of pedicle screw rod instrumentation in the elderly spine with poor bone quality remains challenging. Our study aims to evaluate how the screw bone anchorage is affected by screw design, bone quality, loading conditions, and cementing techniques.

Methods: Micro-finite element (µFE) models were created from micro-CT (μCT) scans of vertebrae implanted with two types of pedicle screws (L: Ennovate and R: S).

[Nonfusion procedures in pediatric scoliosis].

The treatment of early onset scoliosis (EOS) in children is a complex and demanding challenge in the treatment of spinal deformities. Conservative treatment with physiotherapy is indicated in mild forms with a Cobb angle from 10° and additionally a corset treatment with a Cobb angle of more than 20°. After exhaustion of the conservative measures or a progression of spinal scoliosis of 10° or deformities of more than 35°, a surgical approach should be considered in order to prevent respiratory insufficiency as well as severe postural and thoracic deformities.

Georg Schmorl Prize of the German Spine Society (DWG) 2020: new biomechanical in vitro test method to determine subsidence risk of vertebral body replacements.

Purpose: Prevention of implant subsidence in osteoporotic (thoraco)lumbar spines is still a major challenge in spinal surgery. In this study, a new biomechanical in vitro test method was developed to simulate patient activities in order to determine the subsidence risk of vertebral body replacements during physiologic loading conditions.

Methods: The study included 12 (thoraco)lumbar (T11-L1, L2-L4) human specimens.

A Prospective, Randomized Study Evaluating Clinical and Radiographic Efficacy of Lumbar Interbody Fusion Performed Using a Truss Technology-Based Interbody Fusion Device With Homologous Bone or Bone Marrow Aspirate.

Background: Our group used vertebral bone marrow aspirate (BMA) with an anterior truss-based interbody implant to promote fusion. This implant has biomechanical characteristics that may enhance bone on-growth and through-growth and allow for the use of BMA clot alone. The primary end point was comparison of the proportion of patients who achieved fusion with the implant packed with either crushed cancellous homologous bone chips (CCB) alone or with BMA clot alone.

Management of Deep Spinal Wound Infections Following Instrumentation Surgery with Subfascial Negative Pressure Wound Therapy.

Background And Study Aims:  The treatment of infections following a spine surgery continues to be a challenge. Negative pressure wound therapy (NPWT) has been an effective method in the context of infection therapy, and its use has gained popularity in recent decades. This study aims to analyze the impact of known risk factors for postoperative wound infection on the efficiency and length of NPWT therapy until healing.

Implementation of an anaemia walk-in clinic: Feasibility and preliminary data from the Orthopedic University Hospital.

Background: Approximately one in three patients suffers from preoperative anaemia. Even though haemoglobin is measured before surgery, anaemia management is not implemented in every hospital.

Objective: Here, we demonstrate the implementation of an anaemia walk-in clinic at an Orthopedic University Hospital.

Carbon fiber-reinforced pedicle screws reduce artifacts in magnetic resonance imaging of patients with lumbar spondylodesis.

The study investigated whether the use of carbon fiber-reinforced PEEK screw material (CF-PEEK) can reduce magnetic resonance imaging (MRI) artifact formation. Two consecutive groups of patients were treated for degenerative spinal disorders of the lumbar spine with dorsal transpedicular spinal fusion. The first group (n = 27) received titanium pedicle screws.

Development and current use of local antibiotic carriers in spondylodiscitis : Pilot study on reduction of duration of systemic treatment.

Background: The current study situation regarding the duration of systemic antibiotic treatment for spondylodiscitis is inhomogeneous and varies between 4-12 weeks. Due to the many undesirable side effects the aim is to achieve complete healing without recurrence or hematogenous scatter within the shortest possible period of time. The present pilot study investigated whether the additional application of a local antibiotic carrier to the surgically treated intervertebral disc space can contribute to a further reduction of treatment duration.

Adrenoceptor Expression during Intervertebral Disc Degeneration.

Healthy and degenerating intervertebral discs (IVDs) are innervated by sympathetic nerves, however, adrenoceptor (AR) expression and functionality have never been investigated systematically. Therefore, AR gene expression was analyzed in both tissue and isolated cells from degenerated human IVDs. Furthermore, human IVD samples and spine sections of wildtype mice (WT) and of a mouse line that develops spontaneous IVD degeneration (IVDD, in SM/J mice) were stained for ARs and extracellular matrix (ECM) components.

Clinical Outcome After Anterior Lumbar Interbody Fusion With a New Osteoinductive Bone Substitute Material: A Randomized Clinical Pilot Study.

Study Design: Pilot, single-center, single-blinded, parallel-group, randomized clinical study.

Objective: The aim of this study was to pilot a randomized clinical study to evaluate whether instrumented anterior lumbar interbody fusion (ALIF) with a new nanocrystalline hydroxyapatite embedded in a silica gel matrix (NH-SiO2) leads to superior radiologic and clinical outcomes at 12-month follow-up compared with instrumented ALIF with homologous bone.

Summary Of Background Data: ALIF completed with interbody cages is an established technique for performing arthrodesis of the lumbar spine.

Radiological evaluation of kyphoplasty with an intravertebral expander after osteoporotic vertebral fracture.

Spinal deformities due to osteoporotic vertebral compression fractures can be reduced by balloon kyphoplasty, but the correction may be partly lost when the balloon is deflated. The present study aimed to evaluate an intravertebral expander developed to reduce and maintain vertebral body height while cement is injected to correct spinal deformities due to osteoporotic vertebral fractures. The study included 31 osteoporotic vertebral body fractures in 31 patients, classified as A1 according to the AO classification, who underwent kyphoplasty using an intravertebral expander.

Micro-CT and micro-FE analysis of pedicle screw fixation under different loading conditions.

Anchorage of pedicle screw instrumentation in the elderly spine with poor bone quality remains challenging. In this study, micro finite element (µFE) models were used to assess the specific influence of screw design and the relative contribution of local bone density to fixation mechanics. These were created from micro computer tomography (µCT) scans of vertebras implanted with two types of pedicle screws, including a full region-or-interest of 10 mm radius around each screw, as well as submodels for the pedicle and inner trabecular bone of the vertebral body.

Anterior cement augmentation of adjacent levels after vertebral body replacement leads to superior stability of the corpectomy cage under cyclic loading-a biomechanical investigation.

Background: In the operative treatment of osteoporotic vertebral body fractures, a dorsal stabilization in combination with a corpectomy of the fractured vertebral body might be necessary with respect to the fracture morphology, whereby the osteoporotic bone quality may possibly increase the risk of implant failure. To achieve better stability, it is recommended to use cement-augmented screws for dorsal instrumentation. Besides careful end plate preparation, cement augmentation of the adjacent end plates has also been reported to lead to less reduction loss.

Transforaminal lumbar interbody fusion using polyetheretherketone oblique cages with and without a titanium coating: a randomised clinical pilot study.

Aims: We compared the clinical and radiological outcomes of using a polyetheretherketone cage with (TiPEEK) and without a titanium coating (PEEK) for instrumented transforaminal lumbar interbody fusion (TLIF).

Materials And Methods: We conducted a randomised clinical pilot trial of 40 patients who were scheduled to undergo a TLIF procedure at one or two levels between L2 and L5. The Oswestry disability index (ODI), EuroQoL-5D, and back and leg pain were determined pre-operatively, and at three, six, and 12 months post-operatively.

[Current Status of Spine Surgery in Germany: Results of a Survey of Members of the German Spine Society].

Mono- (MSS) and bisegmental spinal fusion (BSS) are frequently performed surgical interventions in German hospitals. Despite the high number of cases, only few data on treatment procedures and concepts for pre-, peri-, and postoperative care are available. The aim of the survey was to gain detailed insights into treatment procedures and medical approaches in elective MSS and BSS care in Germany in order to extract recommendations for improving patient care.

Conservative management of osteoporotic vertebral fractures: an update.

Purpose: Adequate conservative management of osteoporotic vertebral fractures remains important in an aging population.

Methods: We performed a research of multiple databases and present important studies in this narrative review.

Results: The pertinent literature remains scarce and of mixed quality.

[Hybrid stabilization technique with spinal fusion and interlaminar device to reduce the length of fusion and to protect symptomatic adjacent segments : Clinical long-term follow-up].

Introduction: Determination of the extent of spinal fusion for lumbar degenerative diseases is often difficult due to minor pathologies in the adjacent segment. Although surgical intervention is required, fusion seems to be an overtreatment. Decompression alone may be not enough as this segment is affected by multiple factors such as destabilization, low grade degeneration and an unfavorable biomechanical transition next to a rigid construct.

[ALIF and PLIF interposition in low-grade isthmic spondylolisthesis L5/S1 : Longterm-Comparison of interbody fusion techniques (ALIF - PLIF)].

Introduction: For the treatment of isthmic spondylolisthesis two alternative interbody fusion techniques are available, the dorsoventral interposition in ALIF technique and the dorsal access interposition in PLIF technique. Due to the complications of anterior lumbar surgery and in order to avoid a second operation, the dorsoventral fusion technique is becoming uncommon and mainly a pure dorsal supply is performed. The aim of the study was to compare the clinical long-term results of both treatment techniques.

[Management of postoperative wound infections following spine surgery : First results of a multicenter study].

Introduction: The number of spinal surgeries has increased significantly in the last decade, which has led to a correlating increase in the number of problems related to wound healing infection. Current literature has reported a spinal wound infection rate of 0.4 to 20 %.

Small cavity creation in the vertebral body reduces the rate of cement leakage during vertebroplasty.

Cement leakage is the most common complication during vertebroplasty and may result in serious morbidity. Measures to reduce the rate of cement leakage are valuable ways to improve vertebroplasty safety. The present study aimed to evaluate whether creating a small cavity in the vertebral body prior to cement injection would reduce the rate of cement leakage during vertebroplasty.

[History of vertebral body replacement].

Background: Vertebral body replacement after corpectomy is nowadays a standard procedure in spinal surgery.

Objective: Description of the developmental process of vertebral body replacement.

Method: Historical description of the innovations in vertebral body replacement.

[Interbody fusion procedures. Development from a historical perspective].

Background: The development of interbody fusion now stretches over many decades and is still not complete.

Discussion: Due to the lack of appropriate implants, the initial fusions were performed via decortication of the dorsal and lateral structures of the spine, followed by placement of an autograft. Despite acceptable fusion results, better primary stability and higher fusion rates were desired.

[Posterior lumbar interbody fusion implants. Software assisted planning--preliminary results].

Background: Sagittal imbalance, adjacent segment degeneration, and loss of correction due to cage sintering are the main reasons for revision surgery after lumbar fusion. Based on the experience from hip and knee replacement surgery, preoperative software-assisted planning combined with the corresponding cages is helpful to achieve better long-term results.

Objectives: Evaluation of the procedure regarding intraoperative application of preoperative planning and examination to what extent the planning was correct.

[The PLIF and TLIF techniques. Indication, technique, advantages, and disadvantages].

Background: Posterior fusion procedures (posterior lumbar interbody fusion, PLIF; transforaminal lumbar interbody fusion, TLIF) are long-established surgical techniques for lumbar interbody fusion. They differ from anterior lumbar interbody fusion (ALIF) and extreme lateral interbody fusion (XLIF) procedures by approach and associated complications.

Objectives: The posterior fusion procedures PLIF and TLIF are presented and compared with other fusion methods, including advantages and disadvantages.