There is an high incidence of failures of total wrist arthroplasties. We review our experiences in revising total wrist implant arthroplasties to arthrodeses. The most common mode of failure of the arthroplasties in our series was metacarpal loosening with dorsal perforation of the stem. Loosening of the proximal stem, progressive mal-position of the wrist and other causes appeared. We used for the revision arthrodesis in all our cases tricortical iliac crest bone grafts and additional spongiosa transplants from this donor site region. In one case we used a vascularized iliac crest bone graft to bridge the bone defect because of a bad host quality of the recipient area. Fixation was achieved with plates and screws. Our average follow-up period was 32 month. 40 patients with 41 failed wrist implants (3 different types) were treated with this technique. 40 wrist undergoing arthrodesis attained a solid painless fusion after a single operation. In one case a non-union with a loosening of the screws due to using a non-rigid plate was seen. In this case a revision was necessary to achieve a bone healing. All patients were satisfied, pain free and achieved an increased pinch and grip strength after bony fusion (measured with Yamar-Vigorimeter). A persisting loss of carpal height was seen in all cases. Arthrodesis after failed total wrist arthroplasty is a satisfactory salvage procedure even in cases with a bad quality of the recipient area. We recommend a rigid fixation technique to prevent non-unions.
From January 2000 to March 2004 16 thumbs after total avulsion-amputation were replanted in our hospitals. In 15 cases this was successful. In one case the thumb was lost 28 hours after replantation. Mostly the amputation was in the region of the first phalanx or the IP-joint of the thumb. In all cases our operative procedure for this form of amputation was the reconstruction of the vessels with vein grafts after the osteosynthesis and the reconstruction of the tendons. The donorsite region for the grafts was in 12 cases the dorsal forefoot and in 4 cases the distal forearm. In none of these cases there was the possibility of reconstructing both arteries. Mostly only an anastomosis for one artery and one vein could be done. For none of these patients it was possible to reconstruct the nerves primarily. Until now transphers of neurovascular skinislands of longfingers, free nerve transplantations with coaptations to the proximal stump of the injured nerve, free nerve transplantations with coaptations to the trunk of the median nerve or in one case an end-to-side coaptation have been performed to achieve a resensibility of the thumbs. In one case a patient rejected an operative nervereconstruction, because a sprouting of the proximal stump of the injured nerve lead to a (reduced) sensibility of the thumb. In 4 cases a therapy to achieve a resensibility has so far not been carried out. After replantations of injured thumbs necroses of the skin in different kinds were noticed. In 4 cases secondary skinreconstructions were necessary. All 15 successful replanted thumbs achieved very good results concerning function, strength and patient’s satisfaction. Our results don’t agree with the mostly bad results after total avulsionamputations mentioned in literature. We think that the replantation after total avulsionamputation of the thumb has a high chance of being successful and can achieve very good longtime results.
After having completed more than 150 primary knee arthroplasties with a new navigation system both analyzing the position of the implants as well as the soft tissue balancing in each range of motion, we performed the first revision surgeries in February 2001 using this device. At present we have revised 15 arthroplasties with the support of navigation. The reasons for revision were early loosening in 11 cases and instability in 4 cases. Intraoperatively, we were able to analyze the malpositioning of the implants and the disturbed soft tissue balance. In most cases (n = 12), a femoral internal malposition was found. There was, therefore, extreme polyethylene wear on the medial plateau of the tibia and instability of the soft tissues on the lateral side. We were also able to find an incorrect joint-line and a malrotation of the tibial component. In all these cases specific intra-operative kinematics showed us the primary reason for early loosening. The navigation system screen provides not only information about the incorrect angle of the implant position but also indirectly via the kinematics, information about the relationship of the malpositionings between the implants. In many cases (n = 10) there were combined errors in positioning of the implants. The first 15 cases show that malpositioning of knee implants can be analyzed with the new generation of navigation systems. These devices help the surgeon, in the operation room to make his decision how to proceed. The malpositioned implants showed extreme polyethylene wear demonstrating that the positioning of the implants do influence the outcome very much. A useful navigation system in revision surgery is the one which is not related to a specific design of an implant but is usable in all cases so that every implant can be measured.
After having completed more than 150 primary knee arthroplasties with a new navigation system both analyzing the position of the implants as well as the soft tissue balancing in each range of motion, we performed the first revision surgeries in February 2001 using this device. At present we have revised 15 arthroplasties with the support of navigation. The reasons for revision were early loosening in 11 cases and instability in 4 cases. Intra-operatively, we were able to analyze the malpositioning of the implants and the disturbed soft tissue balance. In most cases (n = 12), a femoral internal malposition was found. There was, therefore, extreme polyethylene wear on the medial plateau of the tibia and instability of the soft tissues on the lateral side. We were also able to find an incorrect joint-line and a malrotation of the tibial component. In all these cases specific intra-operative kinematics showed us the primary reason for early loosening. The navigation system screen provides not only information about the incorrect angle of the implant position but also indirectly via the kinematics, information about the relationship of the malpositionings between the implants. In many cases (n = 10) there were combined errors in positioning of the implants. The first 15 cases show that malpositioning of knee implants can be analyzed with the new generation of navigation systems. These devices help the surgeon, in the operation room, to make his decision how to proceed. The malpositioned implants showed extreme polyethylene wear demonstrating that the positioning of the implants does influence the outcome very much. A useful navigation system in revision surgery is the one which is not related to a specific design of an implant but is usable in all cases so that every implant can be measured.
We conducted this prospective randomised and externally evaluated study to investigate whether the use of a navigation system during total knee arthroplasty leads to significantly better results than the hand-guided technique. A total of 240 patients was included in the study. All patients received a condylar knee prosthesis. Two surgeons performed all the operations using the Stryker knee navigation system. Exclusion criteria included the necessity for the primary use of constrained implants. The results revealed a highly significant difference between the two groups in favour of navigation with regard to the mechanical axis, the frontal and sagittal femoral axis and the frontal tibial axis (p <
0.0001). The use of a navigation system was therefore shown to improve the alignment of the implant.
Severe acetabular bone stock loss compromises the outcome in primary and revision total hip arthroplasty. This acetabular deficienca occurs very often in Rheumatoid Arthritis. In 1979 a biologic method was introduced with tightly impacted cancellous allograft in combination with a cemented polyethylene cup for acetabular reconstruction. With this technique it is possible to replace the loss of bone and restore hip function with a standard implant. Because of the poor long term results and our own experience with large solid grafts we started in 1998 to use the impaction grafting in primary and revision hip replacements in Osteoarthritis and Rheumatoid Arthritis.
Between 1998 and 2001 35 acetabular reconstructions were performed in 29 patients with rheumatoid arthritis. 3 Patients were lost to follow up. 24 primary and 11 Revision Arthroplasties were performed. The average age was 55( 22-73. 29 female, 6 male. 58 Patients had additional dysplasia. We had cavitary, segmental and also combined defects. Femoral head autografts were used in all primaries, allografts were used in revision surgery. Firstly the peripheral and central segmental defects were close with a metal mesh, so that only a cavitary defect remained. The cavity was filled with bone chips which were impacred layer by layer. To strabilize these reconstruction cement was used in direct contact with the graft. In the Merle d’ Aubigne Score an improvement in pain, walking ability and function were observed. We had 1case of aseptic loosening, in a 73 year old female. After 10 month the grafts were incorporated. Our results are short term results- compared to the international literature ( Rosenberg et al. ) Nevertheless we can confirm the technique can be used with good results in cases with severe acetabular defects due to rheumatoid arthritis.
