This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.
Human augmentation is used to refer to technologies that improve human productivity or capability, or that somehow add to the human body. Modern improvements in many areas of IT have led to a greater variety of implants and other technologies that could be classed as human augmentation. (1)
The Augmentation of the human body is generally used for the following reasons (2):
- Compensating for missing /injured capabilities
- Markedly improved traits and abilities
- Longer and better life
- Improvement of the human gene pool (2)
- Bone augmentation due to fracture or injury by “Bone Cement” system.
3. Bone Cement
Bone cementwas used in surgeries for the first time in the 1940s to fill gaps in the skull. Complete clinical tests of bone cement compatibility with the human body were performed before their use insurgery. The excellent tissue compatibility ofPMMAallowed bone cement to be used for fixation of head prostheses in the 1950s. (3)
Bone cement is made of two component materials. Bone cement consists of a powder (i.e., pre-polymerized PMMA and orMMAco-polymer beads and a liquid MMA monomer, stabilizer, inhibitor). Both components are mixed and a freeradical polymerizationoccurs of the monomerwhen the components are mixed with the accelerator. The bone cementviscositychanges over time from a liquid into paste which can be safely applied and then finally becomes into solid material.The set time can be controlled to help the surgeon securely apply the bone cement into the bone to fix metal and plastic prosthetic devices to treat osteoporotic compression fractures. (3)
Bone cement is used for various purposes in human body. In this report the following are discussed in detail:
- Vertebral Spine Fracture (Vertebroplasty and Kyphoplasty)
- Femur Head (Cemented Joint Prosthesis)
- Knee Joints (Subchondroplasty)
Vertebroplasty and Kyphoplasty are slightly invasive procedures that are carried out to treat vertebral spine compression fractures (VCF). In vertebral compression fractures, the body collapses into itself producing a "compressed" vertebra. People with osteoporosis or bone marrow cancer are particularly inclined to compression fractures. By replacing the bone cement with the fractured bone part the vertebra height can be restored and offer patients faster recovery and reduces the risk of future fractures. (4)
Vertebroplasty and Kyphoplasty are alike procedures. In Vertebroplasty, bone cement is injected via the hollow needle into the fractured bone. Whereas, in Kyphoplasty a balloon is inserted and inflated to pump up the compressed vertebra to its original height before filling the gap with bone cement. This is repeated for each of the affected vertebra. The cement-augmented vertebra allows to stand straight, reduces pain, and prevents further fractures. (4)
5.1. Clinical Outcomes
Both Vertebroplasty and Kyphoplasty have been shown to be effective in reducing pain from compression fractures. Although better results can be achieved in more recent fractures, quite acceptable results have been reported in chronic cases. (5), (6)
Concerning the long-term effect of Vertebroplasty on pain, good or excellent results in 96% of patients with a mean follow-up of 48 months have been reported. Also, there was a significant improvement in pain and physical functionality in the Vertebroplasty group within the 24 hours period. (7), (8)
No surgery is without risks. The usual complications of any surgery include bleeding, infection, blood clots, and reactions to anesthesia. The risks that should be considered are as follows:
- Rib and sternal fractures: Rib fractures have been rarely associated with Vertebroplasty and Kyphoplasty and fracture of the sternum has also been seen after Vertebroplasty. (9)
- Bone cement leakage: There is a minor chance that bone cement can leak out of the needle into surrounding tissues. This can occur during removal of the needle. The surgeon must closely watch the fluoroscope and prevent it from happening. (9)
- Nerve damage: Spine operations come with the risk of damaging the nerves. These can cause numbness or even paralysis. (9)
A cemented prosthesis is made to have a layer of bone cement between the patient's natural bone and the prosthetic joint component. Polymethylmethacrylate (PMMA) has been used to augment the fixation of distal femur and unstable trochanteric fractures. Excessive cement application and the presence of cement at the fracture site apparently can result in disturbed blood supply and compromised fracture healing. However, if bone cement is applied without these risk factors, it will potentially increase initial stability and reduce the possibility of postoperative fixation failure. (10)
During the procedure the cement is applied via a pressurized injection into the femoral head. The hip is reduced and the cement is allowed to harden with contouring and molding of the femur head by the acetabulum. The absence of free cement is verified radiographically (fluoroscopy) and visually. After surgery, the patients are allowed partial weight bearing for 6 weeks. (11)
There are a few advantages to using bone cement in joint replacement surgeries:
6.1. Clinical Outcomes
- Bone cement allows a surgeon to attach prosthetic joint components to a bone that is to some extent porous from osteoporosis.
- A minor amount of antibiotic material can be added to the bone cement, which allows reducing the risk of infection after surgery.
- The bone cement dries within 10 minutes of application, so the surgeon and patient can be confident that the prosthetic is steadfastly fixed in place. (12)
- The drawback to using bone cement is that it may degrade over time and small pieces of cement can break off, possibly causing problems:
- A degradation of the cement can cause the artificial joint to come loose, which may lead to another joint replacement surgery.
- The cement fragments can irritate the surrounding soft tissue and may cause swelling.
- Although very rare, the cement may enter into the bloodstream and end up in the lungs, a condition that can be life-threatening. (12)
Subchondroplasty (SCP) is a minimally invasive procedure that is carried out to explicitly repair chronic BMLs (Bone marrow lesions) by filling them with a bone cement material. The bone cement is replaced with healthy bone and then slowly resorbed repairing the bone defect. This also resolves the associated edema.
The Subchondroplasty is carried out under fluoroscopy to precisely locate the chronic BMLs. This provides intra-operative X-ray images of the operated area to help the surgeon. The BMLs are diagnosed before the procedure is performed. (13)
During the procedure a reference frame (semi-circular) is placed that allows the surgeon to operate the BML. Then through the skin a pin is inserted into the bone under fluoroscopic imaging. Then a cannula is placed over the pin and via a delivery syringe the bone cement is then injected into the bone. The delivery syringe and cannula are then removed. Lastly, the bone substitute is verified through fluoroscopic imaging. (13)
7.1. Clinical Outcome
A case study was performed at the Rothman Institute in Philadelphia USA, to assess the treatment associated with BML’s using the SCP procedure in patients. (14)
The main findings were as follows:
- Statistically significant improvement in pain relief and function as early as 2 weeks, and continuing at 6 months, 1 year, and 2 years.
- Patients had a reduced rehabilitation time period when compared to total knee arthroplasty (TKA)
- Longer lasting symptom relief than reported outcomes for knee arthroscopy (14)
- 90% of patients had clinically significant improvement in pain at 6 months
- Greater pain reduction than reported for debridement (14)
Function improvement (IKDC)
- 70% of patients had clinically significant improvement in function at 6 months
- Compared with persons aged 51-65 (including individuals with and without knee problems, where the population mean IKDC Score is 74), post-op patients demonstrated an 81%
improvement in standardized function scores (14)
7.2. Advantages and Risks
Subchondroplasty procedure has the following advantages:
- It is an outpatient procedure and the patient is normally on the same day discharged.
- It provides faster recovery and quicker return to the normal life.
- It does not inhibit total knee replacement if it is required in the future. (13)
Other than the typical risks of minimally invasive surgery and standard post operation recovery precautions, the Subchondroplasty does not have any specific drawbacks.
1. Janssen, Cory. Techopedia, Human Augmentation. Techopedia. [Online] Janalta Interactive Inc, 1 1, 2012-2014. [Cited: 12 1, 2014.] http://www.techopedia.com/definition/29306/human-augmentation.
2. Dvorak, Dr. Joseph. The future of Human augmentation. [Online] Muskegon Community College, 10 28, 2010-2011. [Cited: 12 1, 2014.] https://www.youtube.com/watch?v=TbEHz7CADcg.
3. The effect of the type of cement on early revision of Charnley total hip prosthesis. Havelin LI, Espehaug B, Vollset S, Engesaeter L. 10, Bergen, Norway: J Bone Joint Surg Am, 1995 Oct, The Journal of Bone and Joint, Vol. 77. 1543–1550. 1995.
4. Balloon kyphoplasty: one-year outcomes in vertebral body. Ledlie JT, Renfro M. 36-42., Texas, USA: pubmed.gov, 2003, J Neurosurg, Vol. 98(1). 12546386..
5. Acute versus chronic vertebral compression fractures treated with kyphoplasty: early results. Crandall D, Slaughter D, Hankins PJ, Moore C, Jerman J. 418-24., Phoenix, USA: The spine journal : official journal of the North American Spine Society, 2004, Vol. 4(4). 15246303.
6. Treatment of chronic symptomatic vertebral compression fractures with percutaneous vertebroplasty. Brown DB, Gilula LA, Sehgal M, Shimony JS. 319-22, St Louis, USA: American journal of roentgenology., 2004, Vol. 182. 14736654.
7. Long-term observations of vertebral osteoporotic fractures treated by percutaneous vertebroplasty. Grados F, Depriester C, Cayrolle G, Hardy N, Deramond H, Fardellone P. 1410-4., 2000 Dec, Rheumatology (Oxford), Vol. 39(12), p. 12.
8. Management of acute osteoporotic vertebra fractures: a nonrandomized trial comparing percutaneous vertebroplasty with conservative therapy. Diamond TH, Champion B, Clark WA. 257-65., 2003, The American journal of medicine, Vol. 114, p. 4.
9. Prospective evaluation of pain relief in 100 patients undergoing percutaneous vertebroplasty: results and follow-up. McGraw JK, Lippert JA, Minkus KD. 883-6., 2002, Journal of vascular and interventional radiology : JVIR., Vol. 13, p. 9.
10. Intertrochanteric femoral fractures. Mechanical failure after internal fixation. Davis TR, Sher JL, Horsman A, Simpson M, Porter BB, Checketts RG. 26-31., Durham, England.: J Bone Joint Surg Br, 1990 Jan, Vol. 72(1). 2298790.
11. Open Reduction and Cementation for Femoral Head Fracture Secondary to Avascular Necrosis: Preliminary Report. Wood, M. L., McDowell, C. M., Kerstetter, T. L., & Kelley, S. S. 17–23., 2000, The Iowa Orthopaedic Journal, Vol. 20, p. 5.
12. Vivek Sood, MD. Cemented vs. Cementless Alternatives in Joint Replacement. arthritis-health. [Online] 04 18, 2014. [Cited: 12 1, 2014.]
13. Daley, Robert J. http://www.daleymd.com/. [Online] subchondroplasty.com, 1 1, 2014. [Cited: 12 1, 2014.] http://www.daleymd.com/services/procedures-2/subchondroplasty/.
14. Cohen, Dr. Steven B. Initial results from 60 patients with Bone Marrow Lesions that were treated with the Subchondroplasty procedure . Philadelphia, USA: Knee Creations, LLC, 2012. 903.008.