Short- to mid-term outcomes of computer navigation assisted total knee arthroplasty using adjusted mechanical alignment compared to mechanical alignment

Purpose To evaluate efficacy of navigation-assisted total knee arthroplasty (TKA) achieved using adjusted mechanical alignment (aMA) and mechanical alignment (MA) technique. Methods The authors performed a retrospective study enrolled a single-center series of patients who underwent navigation-assisted TKA with aMA (n = 77) and with MA (n = 61) technique. The demographic data was recorded. Functional scores including Hospital for Special Surgery score, Western Ontario and McMaster Universities Osteoarthritis Index score and Forgotten Joint Score-12 were evaluated. In addition, the parameter of resection and soft tissue balance as well as radiographic evaluation was measured and compared between groups. Results The HSS score at 1-month and 6-months postoperatively were significant higher using aMA compared to MA. The postoperative coronal alignment was made with a mean of 1.11° more varus/valgus in the aMA group compared to MA. The femoral prosthesis was positioned in a mean of 2.29° more varus/valgus using aMA compared to MA. The medial extension gap was significantly tighter in the MA group. In addition, the femoral prosthesis in the aMA group was positioned in a mean of 0.77° more external rotation than the MA group. The lateral flexion gap was wider in the aMA group with a mean of 0.71 mm more laxity. Conclusions Both aMA and MA technique in TKA obtained good clinical outcomes. Notably, aMA-TKA grant superior functional scores at 1-month and 6-months follow-up, might due to the preservation of mild constitutional frontal deformity with less release of soft tissue and a biomimetic wider lateral flexion gap was remained.

Gastric perforation caused by secondary systemic amyloidosis

An 82-year-old man, suffering abscess secondary to femoral prosthesis replacement, complained of intractable watery diarrhea and melena. Autopsy disclosed 12 mm-sized perforation at the gastric prepylorus and purulent peritonitis. Amyloid A was deposited in systemic organs and tissues, including the site of gastric perforation. IgM was co-deposited in the glomeruli.

A Case of Cementless Impaction Bone Graft in a Revision Total Hip Arthroplasty Requiring Calcar Reconstruction

Introduction. In cases of bone deficiency or osteoporosis, and especially in revision cases, there were only two options for treatment until the impaction bone graft procedure was proposed. These were cemented or cementless femoral prosthesis. In the early 1990s, the use of impaction bone graft with a cemented mantle had gained popularity and had proven to be clinically effective. In Germany, a cementless impaction bone graft procedure using Corail® (DePuy Synthes) stems was devised, and functional scores were similar to conventional cemented Impaction bone grafts. Case presentation. A 48-year-old man presented with femur loosening of a reamed bipolar arthroplasty performed in 1990. The patient was treated with a cementless impaction bone graft using a Corail® (DePuy Synthes) stem in the femur in revision THA surgery, and the calcar was reconstructed by allograft. Results. At five years, the calcar allograft united with the host bone, and the femoral component showed no subsidence. Conclusion. Calcar reconstruction with a strut allograft, aimed at preventing sinking of the stem was key in this operation. Surgical indication for femoral cementless impaction bone graft should be for loosened femoral prosthesis in a type II Paprosky classification, where only the cortical bone of the isthmus is partially affected, cortical thinning does not exist, and it is mechanically strong enough for the allograft tip impaction. The procedure was safely feasible through the direct anterior approach.