Treating Osteoporotic Spinal Fractures in Elderly Patients via a Modified Clinical Bone Cement Injection Technique

Summary

Presented here is a modified procedure for minimally invasive injections of bone cement to treat osteoporotic spinal fractures in elderly patients.

Abstract

The minimally invasive injection of bone cement (MIIBC) is an effective way to treat senile osteoporotic spinal fractures (OSF) in clinical practice. However, the intraspinal dura and nerves may be damaged when the puncture needle passes through the pedicle. Therefore, in this protocol, the puncture site was optimized during the surgery, selecting the same 1-2 cm away from the surface projection of the diseased vertebra. The needle was punctured along the lateral cortex of the pedicle from the junction of the pedicle and the vertebral body into the vertebral body. Meanwhile, bone cement was used as a filling material, and the MIIBC was performed by a percutaneous puncture at the external edge of the pedicle under C-arm fluoroscopy. This modified puncture site is far away from the spinal canal as possible, thereby reducing the risk of the puncture needles penetrating the spinal canal and damaging the nerves and dura mater. In conclusion, a modified MIIBC by percutaneous lateral pedicle puncture can effectively relieve pain in elderly patients with OSF.

Introduction

Osteoporosis is a common disease among middle-aged and elderly women. Statistics show that about 54% of postmenopausal women have abnormal bone density, and the chance of vertebral fracture over the age of 50 is about 32%¹. Osteoporotic spinal fractures (OSF) occur most commonly in women and are mainly compression fractures caused by direct or indirect external forces^1,2. After the fracture, the sagittal balance of the spine is broken, resulting in vertebral deformation, diffuse lumbar and back pain, and kyphosis². In addition, some patients also experience abdominal pressure and breathing difficulties³. Clinical trials have reported that the key to the treatment of OSF is the restoration of bone continuity⁴. Without effective and timely treatment for OSF patients, it is easy for spinal deformities, secondary nerve injury, spinal canal stenosis, angulation deformity, delayed fracture healing, and bone nonunion to occur, and the lives of the patients may even be threatened⁵.

Current clinical treatments for OSF include conservative treatment and surgical treatment⁶. Although the conservative treatment of OSF can provide temporary relief of the symptoms, the course of treatment is long, and the recovery of the injured vertebral height is poor⁷. Overall, the traditional conservative treatment of OSF requires patients to stay in bed for a long time, and its overall efficacy is not ideal. For now, clinical, surgical treatment for OSF embraces traditional open internal fixation, Sextant minimally invasive pedicle screw fixation, percutaneous vertebroplasty (PVP), and percutaneous kyphoplasty (PKP)⁸. Similar to the conservative treatment of long-term bed rest, traditional open internal fixation can lead to aggravated osteoporosis, deep venous thrombosis of the lower limbs, lung infection, urinary tract infection, calculi and decubitus, and other complications, which seriously affect the quality of life of the patient and cause a high disability rate⁹. Nevertheless, Sextant minimally invasive pedicle screw fixation is a complicated operation with a long operation time, and the operation itself can further aggravate secondary injury of the diseased vertebra¹⁰. Obviously, the characteristics of lost vertebral bone density in senile OSF patients are more likely to lead to screw loosening and even removal, resulting in the failure of the internal fixation surgery¹¹.

As commonly used clinical treatments for a senile osteoporotic spinal fracture, PVP and PKP can restore vertebral function and improve the mobility of patients with higher surgical safety and better postoperative pain relief. However, the merits and demerits of both in treating osteoporotic spinal compression fractures are still debated. High-pressure perfusion in PVP surgery can cause leakage of the bone cement into the vertebrae, thus damaging the spinal cord and nerve roots and reducing the surgical effect to a certain extent¹². Compared with PVP, PKP can observably reduce and avoid the risk of bone cement leakage, but the operation is longer¹³. Inevitably, the use of a balloon to dilate the diseased vertebra during PKP surgery also carries a potential risk of secondary vertebral injury¹⁴. Therefore, in this study, on the basis of PVP, elderly patients with OSF were treated by optimizing the puncture site during surgery, thus avoiding the risk of the spinal cord and nerve injury caused by the puncture itself. In this protocol, the case of a 68-year-old female patient with OSF who underwent a modified minimally invasive injection of bone cement (MIIBC) for the treatment of a seventh thoracic vertebra fracture is presented in detail.

Protocol

The surgical operation using MIIBC for the treatment of an osteoporotic fracture of the seventh thoracic vertebra in a 68-year-old woman was approved by the Ethics Committee of Linfen People's Hospital of Shanxi Medical University (T20220829006). The patient provided written informed consent.

1. Collection and recording of the patient's medical history

1. Communicate with the patient to determine the history of trauma, heavy lifting, bumpy rides, jerking, or even coughing.
   ​NOTE: The main clinical manifestations of OSF are as follows: (1) pain, which can be acute or chronic lumbago and back pain or body pain and even obvious limitations in rolling up and down activities and walking activities; (2) spinal deformation, which is mainly manifested as kyphosis, lateral curvature, shortened height, a humpback, and thoracic deformity. In cases of spinal cord compression, severe complications may occur, such as paraplegia and abdominal compression, which may affect cardiopulmonary function.

2. Pre-surgical examinations

1. Physical examination
   1. Check for percussion pain and pressing pain in the chest, waist, and back. Check the lower extremities for sensory and motor changes.
2. Magnetic resonance imaging (MRI)
   1. Perform MRI (see Table of Materials) to identify acute or old vertebral fractures, as shown in Figure 1.
      NOTE: Newly fractured vertebrae show obvious edema around the tissue. Surgery is prohibited for old vertebra fractures.
3. X-ray examination
   1. Perform an X-ray (see Table of Materials) to examine the vertebral changes and bone density in the cuneiform lesions, as shown in Figure 2.
4. Computed tomography (CT) examination
   1. Perform CT (see Table of Materials) to examine the integrity of the posterior wall of the fractured vertebra, and determine if a vertebral fracture mass is present in the vertebral canal, as shown in Figure 3.
5. Bone mineral density (BMD) examination
   1. Perform dual-energy X-ray absorptiometry (DXA) (see Table of Materials) to measure the BMD of the spine, as shown in Figure 4.

3. Patient positioning

1. Place a chest pad (see Table of Materials) under the patient's chest to maintain the patient in a prone position. Place a soft pad (see Table of Materials) under the lower leg to bend the knee to 20°. See Figure 5 for the specific details on the patient positioning.
   ​NOTE: Remind the patient to relax the thoracolumbar and back muscles to facilitate the later puncture operation.

4. Surgical procedure

1. Perform intraoperative digital radiography (DR) and puncture localization.
   1. Fix the Kirschner wire (see Table of Materials) on the body surface, and use the C-arm of the DR machine (see Table of Materials) for intermittent imaging to identify and label the surface projection of the diseased pedicle, as shown in Figure 6.
      NOTE: The location of the diseased pedicle should be evaluated comprehensively based on the results of step 3.1, step 4.1, step 5.1, and step 6.1.
2. Perform needle puncture and bone cement injection.
   1. Locate the injection point at 1-2 cm outside the surface projection of the outer edge of the pedicle. Perform full invasive anesthesia with 2% lidocaine (see Table of Materials) along the skin of the puncture site toward the pedicle, as shown in Figure 7.
      NOTE: The puncture point is not at the body surface projection of the injured pedicle but is 1-2 cm outside the body surface projection on the outer edge of the pedicle.
   2. Under lateral DR imaging, adjust the orientation of the puncture needle to be consistent with the midline of the seventh thoracic vertebra, and strike the puncture needle to the outer edge of the pedicle with a surgical hammer (see Table of Materials). Next, push the puncture needle to the anterior vertebral 1/3 junction under lateral DR imaging.
      NOTE: When the tip of the puncture needle reaches the posterior edge of the vertebral body, the DR imaging above the prone position should show that the puncture needle passes right over the outer edge of the pedicle. When the puncture needle reaches the anterior 1/3 junction of the vertebral body, the DR imaging above the prone position should indicate that the tip of the puncture needle is located in the center of the vertebral body.
   3. Fill the syringe with the prepared viscous bone cement (see Table of Materials), and slowly inject it into the vertebra under lateral DR imaging. Insert the pillow inner to push the bone cement remaining inside the puncture needle (see Table of Materials) into the vertebral body.
   4. Pull out the puncture needle by turning it backward. After pressing the puncture site for 3-5 min, wrap the puncture site with sterile surgical gauze (see Table of Materials), as shown in Figure 8.
      ​NOTE: Bone cement should be freshly prepared when being used. If obvious leakage is found during the injection of the bone cement, the injection should be terminated immediately.

5. Postoperative care

1. Administer oxygen, and monitor the vital signs of the patient in a supine position for 6 h after surgery.
   NOTE: On the first day after surgery, the patient can stand and walk under the protection of the lumbar support device. If the thoracolumbar X-ray re-examination is normal, the patient can be discharged from the hospital 2-3 days after surgery.

Results

The OSF patient selected for the modified MIIBC had no history of trauma, heavy lifting, bumpy rides, jerking, or even coughing. Further physical examination showed that the patient had no percussion pain or pressing pain in the chest, waist, or back and had normal sensation and movement in the lower limbs. A new vertebral fracture was first identified in the seventh thoracic vertebra with perivertebral edema using MRI imaging (Figure 1). After that, the X-ray examination demonstrated a vert...

Discussion

Traditional open internal fixation is used with patients who have the neurological symptoms of a vertebral compression fracture and a fractured mass entering the spinal canal and pressing on the spinal cord and nerve roots¹⁵. This technique is especially suitable for individuals with severe violent vertebral trauma, such as from a car accident or falling from height. This kind of emergency surgery usually requires spinal canal decompression, which has a long operation time and a large area of trau...

Materials

Name	Company	Catalog Number	Comments
Bone cement	Heraeus Medical GmbH	61805335
Chest pad	Hengshui Hejia Medical Device Co., Ltd.	1.00297E+13
Computed tomography instrument	General Electric Company	Discovery  CT750 HD
Dualenergy X-ray absorptiometry	General Electric Company	Discovery  XR656
Kirschner wire	Tianjin Yutong Medical Device Factory	210401
Lidocaine	Shiyao Silver Lake Pharmaceutical Co., Ltd.	C22B042
Nuclear magnetic resonance apparatus	General Electric Company	Achieva 1.5T
Povidone iodine solution	Wen Shui Greatly Industrial Co., Ltd.	20220801
Puncture needle	Dragon Crown Medical Co., Ltd.	22040601
Soft pad	Yueyang Zhengyang Medical Device Co., Ltd.	HRT445
Sterile covering	Suqian Hongzhilong E-commerce Co., Ltd.	56200331882
Sterile surgical gauze	Hainuo Group Co. Ltd.	7918087
Surgical hammer	Hengshui Wankai Trading Co., Ltd.	5.20808E+11
Syringe	Shandong Weigao Group Medical Polymer Co., Ltd.	20220101
Vertebroplasty bone cement filler set	Shenzhen Hanqiang Medical Device Co., Ltd.	TF210301
X-ray instrument	Shenzhen Rayvision Technology Co., Ltd.	ALC-200H