Zimmer Knee Replacement NexGen Lawyer is any attorney that is currently involved in litigation with the Zimmer company over their knee implant systems that goes by the brand name of NexGen. There have been over one hundred fifty thousand of these systems installed surgically in patients throughout the United States and elsewhere. It is now becoming apparent, that the number of people who require corrective surgery after having the implant installed has risen to unacceptable levels. Almost all of these surgeries are for the same reason and that is the implant is becoming loose and starts to become ineffective. Surgeons are now calling for the Zimmer company to voluntarily recall their product so that all patients with this system, can have the problem fixed. If you have had this knee implant installed and are having any problems you should contact both your doctor and an attorney. Symptoms of an defective device include trouble walking and standing up from a sitting position.