Visual, dimensional, material and functional analysis could not be performed as the device was not returned.However, provided x-ray shows the screw fractured at the shaft.Device and complaint history records review could not be performed as a valid lot code was not provided and could not be obtained.From the xia ifu: "while the expected life of spinal implant components is difficult to estimate, it is finite.These components are made of foreign materials which are placed within the body for the potential fusion of the spine and reduction of pain.However, due to the many biological, mechanical and physicochemical factors which affect these devices but cannot be evaluated in vivo.Delayed union or nonunion: internal fixation appliances are load sharing devices which are used to obtain alignment until normal healing occurs.In the event that healing is delayed, does not occur, or failure to immobilize the delayed/nonunion results, the implant will be subject to excessive and repeated stresses which can eventually cause loosening, bending or fatigue fracture.The degree or success of union, loads produced by weight bearing, and activity levels will, among other conditions, dictate the longevity of the implant.If a nonunion develops or if the implants loosen, bend or break, the device(s) should be revised or removed immediately before serious injury occurs." it was reported that the patient did not fuse after 1 year of implantation.According to the ifu, delayed union can lead to fatigue fracture.As the device was not returned, a definite root cause cannot be determined, but likely fractured in fatigue due to delayed union.
|