Wright Medical Technology Conserve Plus Total Resurfacing Hip System

 The Wright Conserve Plus Total Resurfacing Hip System is a synthesized metal-on-metal implant devised to replace the hip bone which has been manufactured by Wright Medical Technology.

 There are two components that comprise this hip resurfacing device:  

The Femoral Component - a part of the device that was partly made of metal and plastic in spherical form reshaping and capping the bone located at the top of the thigh with a small neck attached that is to be inserted into the femur bone. 


Acetabular shell - a shallow cup that is used as a substitute for the injured socket of the hip.

 The implant was designed in such a way that will allow both the spherical bone and cup pelvis socket to rub against each other. 

In comparison to traditional hip replacement, the hip resurfacing system takes on a minimally invasive approach by recovering the hip ball and reconstructing its natural anatomy. 

It was created to help people with injured hip bones caused by accident and those that have congenital defects that led to its dysfunction.  

However, due to its unique nature and procedures as to which it is applied; hip resurfacing has its own risks that appear to be of greater frequency as compared to that of a traditional total hip replacement. 

Hip resurfacing system presents risks that may come together with increased failure rate, femoral bone fracture and thinning of the bone's neck, avascular necrosis (dysfunction of the bone brought about by lack of enough blood supply), susceptibility to heterotopic ossification (growth of an unnecessary bone located around the hip causing rigidness and further disability), blood stream disseminated with a higher level of metal ions accumulated overtime, and allergy-like metallic reactions.  In addition, its long-term results are yet to be discovered. 

Despite having known the possible risks that the hip replacing system may pose, it has not deterred Wright Medical Technology from endorsing their product as safe and effective.  

 Having gone through pre-market notification, the Conserve Plus Hip Resurfacing System successfully acquired clearance through the FDA 510 (k) process (a device approval process that grants the permission for a medical device to be distributed into the market once proven to be "substantially equivalent" as safe and effective as another lawfully marketed device designed for the same usage), and was made available to the market. 
Being FDA 510 (k) approved, the Wright Conserve Plus is made eligible to the market and patients without having to go through a series of appropriate trials to confirm its safety and effectiveness.

The process' capability of ensuring safety and effectiveness has been considered as a loophole concerning some medical experts. The Safety of Untested and New Devices Act of 2012 is working on having numerous processes regulated including the FDA premarket notification, 510 (k).

URL References:
http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DeviceApprovalsandClearances/Recently-ApprovedDevices/ucm191091.htm
http://www.ganapathihipkneesurgeon.com/hip%20resurfacing.html

Conventional Hip Replacement Alternative

Wright Conserve, a family of synthesized hip implants, was structured with metallic ball and cup bearings to employ a bone sparing technique. Wright Medical Technology Inc. is the manufacturer and distributor of the all-metal implant.  The BFH Technology, as named by Wright, is the type of technology these medical devices are currently utilizing.  BFH Technology or Big Femoral Head, mimics the femoral bone's dimensions in order to deliver better range of motion, and lessen the possibility of joint dislocation. Its metal to metal structure was devised for added durability to avoid premature implant wear.




The Wright Conserve series is composed of two hip resurfacing systems:

Conserve Partial Resurfacing Implant - this process, by the name itself, does not completely work on the entire hip bone but reuses the well-conditioned pelvic bone socket replacing only the femoral bone (the ball-shaped bone at the top of the thigh) with a metallic component of the same shape.

Conserve PLUS Total Resurfacing Implant - is composed of 2 metallic materials: a ball-shaped metal devised to mimic the femoral bone, and a metallic shallow cup that serves as a replacement to the damaged socket of the pelvic bone.

Although two components of this system possess a slight difference, they both work on achieving the same goal.  The Wright conserve system minimally invades a recipient's body by not replacing the hip bone albeit conserving it giving way to the reconstruction of its anatomical biomechanics providing improvement with stability, greater mobility, and reducing disability and trauma, as opposed to having the hip bone including its socket taken out and substituted with an implant that may be made separately of plastic, metal, and ceramic with traditional hip replacement.

Wright Conserve gained clearance to be made available to the market through the 510 (k) process, a pre-market notification process by the United States Food and Drug Administration.

An FDA device approval process, also referred to as the 510 (k) process, requires all Class III medical devices, and some Class I and II devices to submit a pre-market notification. The device is made eligible to enter the market once proven as "substantially equivalent" as safe and effective as another lawfully marketed device.

Wright Conserve was reportedly linked to a number of possible health problems despite being a good alternative to conventional hip replacement.

Recipients of the implant may be made vulnerable to the following serious health risks:

•    Femoral bone fracture
•    Femoral neck thinning
•    Heterotopic ossification - formation of an unnecessary bone around the hip leading to immobility
•    Avascular necrosis - deterioration of the bone due to lack of blood supply

URL References:

http://www.fda.gov/medicaldevices/deviceregulationandguidance/howtomarketyourdevice/premarketsubmissions/premarketnotification510k/default.htm
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/overview/default.htm
http://www.wmt.com/conserve/physicians/learnaboutconserve/default.asp
http://www.wmt.com/bigfemoralhead/physicians/advantages.asp
http://www.medicinenet.com/total_hip_replacement/article.htm

FDA Tightening of 510(k) Possibly Caused by Profemur Z

The 510(k) process is a process which the United States Food and Drug Administration (FDA) uses to approve many Class II medical devices sold in the United States. During this process the FDA does not "approve" medical devices; they "clear" them for availability on the market. After a device gains 510(k) approve it will be given a 510(k) number.   The number will not expire after it is given. The companies must still comply with all FDA regulations to continue to sell their products in the United States. 

Applicants asking for 510(k) clearance ask the FDA’s examiners to clear their device because it is“substantially equivalent” to an existing device.   The FDA has started to reject a bigger number of 510(k) applicants since June, 2011. The FDA has also tightened up some parameters that a device can be approved. In the past, applicants frequently pointed to as many as 30 predicate devices.  From now on however, the FDA suggests that it will only consider on main and one secondary predicate device. 

The tightening of the FDA reigns of the 510(k) process could be caused by several devices approved by the 510(k) process have become the topic of several medical lawsuits.  One particular device, the Wright Profemur Z hip implant,  has recently come under scrutiny because of its unusually high 11.2% failure rate within 3 years of implantation.  The most common complaint of the Profemur Z hip implant is that it is prone to breaks, especially in the femoral neck portion. 

Patients who have had their Profemur Z implant fail will have to get further surgeries to fix the broken implant.  The way Wright was able to get the Profemur Z implant approved through the 510(k) process was it claimed the implant was already similar to other hip replacement systems on the market.   Wright was able to get 510(k) approval and was able to skip the FDA required human trails.Because of this high failure rate many patients have begun to file lawsuits against Wright. 

URL References:

http://www.timesunion.com/business/press-releases/article/New-Lawsuit-filed-on-Wright-Profemur-Hip-3401646.php

http://www.embedded.com/electronics-news/4370059/FDA-s-510-k--gets-tougher--more-predictable