Intraosseous Injections

Key Points

Knee osteoarthritis treatment summary:
- Intra-articular (IA) arthrocentesis (if needed)
- 3 to 8 mL IA (if needed)
- 5 to 10 mL tibial plateau intraosseous (IO)
- 5 to 10 mL femoral condyle IO
Patellofemoral osteoarthritis treatment summary:
- IA arthrocentesis (if needed)
- 3 to 8 mL IA (if needed)
- 5 to 10 mL femoral trochlear IO
- 2 to 3 mL patella IO
Hip osteoarthritis treatment summary:
- IA arthrocentesis (if needed)
- 3 to 8 mL IA (if needed)
- 5 to 8 mL acetabular IO
- 5 to 10 mL femoral head IO

Pertinent Anatomy

To understand the role of intraosseous (IO) injections in the treatment of advanced osteoarthritis with experienced practitioners, it is important to understand the functional anatomy of subchondral bone. Subchondral bone is located beneath the calcified cartilage line forming what is known as the osteochondral unit. The structure consists of a plate of cortical bone, where the bone marrow and trabecular bone areas emerge. Despite the calcified cartilage layer and the cortical plate being nonporous, it is well known that communication between the articular cartilage and subchondral bone does exist ( Fig. 34.1 ). The intercommunication between these layers has been identified to play a more significant role in osteoarthritis (OA) progression than previously thought.

Pathophysiology

Although the pathophysiology of joint osteoarthritis has long been attributed to wear and tear of articular cartilage over time, a growing volume of evidence suggests that joint osteoarthritis may be the result of a multidimensional change in the whole joint inflammatory environment. It is proposed that the inflammatory state of other structures such as synovium and subchondral bone can contribute to the overlying health of the joint. Significant research has identified subchondral bone as a primary starting place for such pathologic changes and is illustrated through objective findings such bone marrow edema. Because of the cross-talk between subchondral bone and articular cartilage, lesions in the subchondral tissue can ultimately affect the overall health of articular cartilage and lead to degeneration, if not properly treated. This chapter provides instruction on targeting subchondral bone in the treatment of joint pain, particularly for hip and knee osteoarthritis. Other less common anatomic locations such as the ankle, hand, foot, shoulder, and clavicle will also be demonstrated.

Treatment Options and Published Studies

Treatment options for bone marrow lesions include bisphosphonates, extracorporeal shock wave therapy, arthroplasty, subchondroplasty with bone cement (calcium phosphate or polymethyl methacrylate), platelet-rich plasma (PRP), bone marrow concentrate (BMC), and mesenchymal stem cells. ^, Astur et al. performed a review of subchondroplasty with calcium phosphate that showed, in 164 subjects, significant improvement in the International Knee Documentation Committee (IKDC) score or Knee injury and Osteoarthritis Outcome Score (KOOS) and 70% reduction in total knee arthroplasty at 2 years. Side effects were one deep venous thrombosis and two cases of extravasation of cement into the joint, and 25% still had complaints of pain.

Sanchez et al. conducted a study ( n = 30) of case-matched IO and intra-articular (IA) PRP versus IA alone in patients with severe medial or patella femoral OA. They used leukocyte-poor PRP, low concentration (1.5 to 2.5×) with 5 mL injected into the medial tibia plateau (MTP) and medial femoral condyle (MFC) 2 cm above the chondral surface (i.e., 10 mL injected into subchondral bone of each knee). The IO and IA group had significant improvements in KOOS, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and visual analog scale (VAS) score in comparison with the IA alone group at the 6- and 12-month follow-up intervals. They reported that 53% and 46.7% reached the minimum clinically important difference (MCID) for pain reduction at 6 and 12 months, respectively, versus 26.7% and 16.7% for the IA only group. Fiz et al. treated 40 patients with severe hip OA who failed IA PRP with IA 8 mL and IO (5 mL each in acetabulum and femur), placing the PRP 1 cm above the bone. There was significant improvement in WOMAC and Hip disability and Osteoarthritis Outcome Score (HOOS), 40% met MCID at 12 months, and there were no adverse events.

Hernigou recently published outcomes on long-term follow-up (mean 12 years) for young patients with bilateral knee steroid – induced osteonecrosis. One knee was randomized to receive total knee arthroplasty, and the other knee received autologous BMAC. There were 30 patients and 60 knees injected with 10 mL into each of the medial and lateral tibial and femoral compartments of the knee (i.e., 40 mL injected into the subchondral bone of each treated knee). Both groups had similar knee scores, with 21 of 30 preferring the BMAC-treated knee. There were no serious adverse events in the BMAC-treated knee; the surgery knees had one infection, five had thrombophlebitis, nine required transfusions, and six required revision surgery, whereas only three patients in the BMAC group received a total knee arthroplasty (TKA) at 6, 8, and 12 years later. Another study published by Davidson et al. presented outcomes for 49 patients (age 10 to 17 years old) with osteochondritis dissecans who were treated using high-volume subchondral BMAC, and 76.9% had healing on postprocedural imaging and no serious side effects. Kasik et al. treated 20 patients with knee arthritis and bone marrow edema with a subchondral injection of BMAC and demineralized bone matrix in addition to arthroscopic surgery, with a mean of 14.5-month follow-up. VAS decreased from 7 to 1.3, IKDC scores increased from 29.2 to 66.1, and three of the four patients who had postprocedure imaging showed improvement. Lastly, Kyle et al. reported on two cases of knee subchondral edema treated with IO BMAC, and both had symptom and imaging improvements.

An additional study published in 2018 by Hernigou et al. with 30-year follow-up looked at outcomes for the treatment of stage I or II hip osteonecrosis ( Fig. 34.2 ) with cellular therapy versus core decompression. The study enrolled 125 patients (i.e., 250 hips) with bilateral hip osteonecrosis from 1988 to 1998; the hip with the larger-sized osteonecrotic lesion on magnetic resonance imaging (MRI) was treated with percutaneous cellular therapy (i.e., BMAC) and the hip with the contralateral smaller lesion was treated with core decompression. At the most recent follow-up (average of 25 years post treatment), 24% (i.e., 30 hips) in the cellular therapy group versus 76% (i.e., 95 hips) in the core decompression group had undergone total hip arthroplasty. In addition, only 28% versus 72% also had progression to collapse on repeat MRI at the follow-up, cellular therapy versus core decompression, respectively. Several additional studies have also been published on the topic of cellular therapy for the treatment of hip osteonecrosis, with the goal of developing best practices for treatment.

The current published research demonstrates very promising results for the use of BMAC to treat bone marrow lesions of the knee and osteonecrotic lesions of the knee and hip. There is some reported positive benefit of IO PRP for subchondral lesions in OA but not as robust.

Technique

Fluoroscopic Guidance: Knee Osteoarthritis

Patient position: Supine, knee in extension. Alternatively, can place the knee in hook lying with a bolster under the knee for support.
Clinician position: Contralateral side as the treatment limb.
Setup: Sedation or MAC optimal, Completely sterile field,

Equipment Needed

25- to 22-gauge needle
18- to 15-gauge bone trocar 1-inch to 2.7-inch length
Automated power driver and/or mallet
Syringes as necessary for volume

Procedural Steps

1.

Tibial Plateau IO Infiltration:
- a.
  
  Using fluoroscopic guidance, the medial joint line is identified in the anteroposterior (AP) and lateral views. Ensure the medial and lateral tibial plateau are aligned in the lateral view and the anterior and posterior plateaus are aligned in AP. Mark the skin approximately 2 cm distal to the joint line and centered in the midline sagittal plane ( Fig. 34.3 ).
  
  Fig. 34.3
  
  Subchondral bone injections for joint osteoarthritis. (A) Subchondral bone injections for Tibial plateau (1) and Medial Femoral Condyle (2). (B) Subchondral bone injections for Patella (3) and femoral condyle (4).
  
  Courtesy of Mikel Sanchez.
- b.
  
  If available, linear ultrasound should be used to identify vasculature that could course in the needle trajectory. Use color flow Doppler to identify smaller vessels. Adjust needle entry/skin mark to avoid vasculature.
- c.
  
  Optional to add a small amount of local anesthetic, with 0.25% ropivacaine being the preferred choice.
- d.
  
  An 18- to 15-gauge trocar used for bone biopsy is introduced into the skin and advanced down to the periosteum ( Fig. 34.4 ).
  
  Fig. 34.4
  
  Bone trocar advanced into subchondral bone of tibial plateau with injectate ready for infiltration.
- e.
  
  Under fluoroscopic guidance, the trocar is advanced approximately 1.5 to 2.0 cm, directed in a parallel trajectory toward the articular surface, into the medial portion of subchondral bone in the tibial plateau ( Fig. 34.5 ).
  
  Fig. 34.5
  
  (A) Anteroposterior and (B) lateral fluoroscopy views of bone trocar in subchondral bone.
- f.
  
  Once the trocar is correctly placed, it is optional to inject contrast to view the spread of injectate through the bone and observe if there is excess vascular uptake.
- g.
  
  Approximately 5 to 8 mL of injectate is infiltrated through the trocar.
2.

MFC IO Infiltration:
- a.
  
  Using fluoroscopic guidance, the medial joint line is identified in the AP and lateral views. Ensure the medial and lateral femoral condyles are aligned in the lateral view and the anterior and posterior plateaus are aligned in AP. Mark the skin approximately 2 cm proximal to the joint line and centered in the midline sagittal plane ( Fig. 34.6 ).
  
  Fig. 34.6
  
  Bone trocar is advanced into subchondral bone, approximately 2 cm proximal to the joint line.
- b.
  
  If available, use ultrasound to identify vasculature that could course in the needle trajectory. Use color flow Doppler to identify smaller vessels. Adjust needle entry/skin mark to avoid vasculature.
- c.
  
  Optional to add a small amount of local anesthetic, with 0.25% ropivacaine being the preferred choice.
- d.
  
  The trocar is advanced to the level of the periosteum and again advanced 1.5 to 2 cm toward the medial portion of the femoral condyle, in a parallel trajectory to the articular surface ( Fig. 34.7 ).
  
  Fig. 34.7
  
  (A) Anteroposterior and (B) lateral fluoroscopic views of bone trocar in the subchondral bone in medial femoral condyle.
- e.
  
  Once the trocar is in the desired position, it is optional to inject contrast to view the spread of injectate through the bone and observe if there is excess vascular uptake.
- f.
  
  Five to 8 mL of injectate is infiltrated into the subchondral bone.
3.

Lateral Femoral Condyle: The same landmarks and technique are used for the lateral femoral condyle, except using the lateral joint line as a starting point. See Fig. 34.8 as a reference for the placement of the bone trocar in the middle portion of subchondral bone in the lateral femoral condyle.

Fig. 34.8

Anteroposterior fluoroscopic view of bone trocar advanced into subchondral bone of lateral femoral condyle.

Courtesy of Chris Williams.
4.

Patellar IO Infiltration: If a patient has significant patellofemoral degeneration, IO infiltration can also be used in treating the patella.
- a.
  
  Under fluoroscopic guidance, the midlateral or medial portion of the patella is identified in lateral and AP views.
- b.
  
  The bone trocar is advanced to the level of periosteum and advanced approximately 1 to 2 cm toward the middle portion of the patella ( Fig. 34.9 ).
  
  Fig. 34.9
  
  (A) Anteroposterior and (B) lateral fluoroscopic views of bone trocar placement into the patella.
  
  Courtesy of Chris Williams.
- c.
  
  Once proper trocar placement is achieved, it is optional to inject contrast to view the spread of injectate through the bone and observe if there is excess vascular uptake.
- d.
  
  Two to 4 mL of injectate can be infiltrated into the patella.

Alternative Techniques

For femoral condyle and tibial plateau IO injections, one can also directly target a specific bone marrow lesion as seen on MRI. Technique would be similar, except instead of targeting 2 cm above or below the joint line and injecting subchondral 1.5 to 2 cm into the bone, vary needle position to match specific lesion ( Fig. 34.10 ).