Background

A stem sitting proud (SP) or that above the final rasp position remains in some patients who undergo hip replacement using proximally coated tapered wedge stems. Surgeons may face challenges providing the best fit due to unpredictable stem seating. Zimmer Inc. introduced a new rasp to solve this issue but the clinical results of this rasp have not yet been published. Therefore, we aimed to address the following: 1) What is SP incidence using a proximally coated cementless tapered wedge stem? 2) Does the new rasp system improve seating height? 3) What are the risk factors of SP?

Primary total knee arthroplasty is associated with considerable blood loss, and allergenic blood transfusions are frequently necessary. Because of the cost and risks of allogenic blood transfusions, the autologous drainage blood reinfusion technique has been developed as an alternative. A number of studies have compared reinfusion techniques with standard suction drainage, but few reports compared with no drain use. We analyzed early results after primary total knee arthroplasty using autologous drainage blood reinfusion and no drain.

We selected 30 patients who underwent primary total knee arthroplasty using no drain between November 2005 and March 2006 and matched for age and gender with 30 patients who underwent primary total knee arthroplasty using autologous drainage blood reinfusion technique between January 2003 and October 2005. All operations were done under pneumatic tourniquet and meticulous hemostasis was performed after deflation of the tourniquet. We have retrospectively reviewed the preoperative data (age, gender, body mass index, diagnosis, history of the knee surgery, infection and anticoagulant therapy, and medical cormorbidities) and the postoperative data (hemoglobin, hematocrit and platelet during hospitalization, the amount of allogenic blood transfusion and narcotics, complications, rehabilitation process, and clinical scores).

All preoperative and postoperative variables except the postoperative second and seventh days hemoglobin and 2nd day hematocrit showed no significant differences between two groups. The hemoglobin and hematocrit also showed no significant differences at the postoperative fourteenth day.

The autologous drainage blood reinfusion method in primary total knee arthroplasty does not have significant clinical benefit over no-drain method with regards to allogenic blood transfusions, narcotics uses, the incidence of complications and rehabilitation processes.

We evaluated 3 cases of ceramic-on-ceramic THA in that the evidence of the impingement between the metal neck and the ceramic liner was found.

Between July 2007 and January 2008, impingement between the metal and the ceramic liner was found in 3 cases of ceramic-on-ceramic THA during re-operation. The re-operation was performed 3–6 years after the primary surgery because of ceramic head fracture, deep infection and cup loosening. All patients frequently sat on the floor in tailor fashion but did not have any sound in the hip after THA.

In all cases, V-shaped indented wear scar was found on the postero-superior aspect of the metal neck. Two ceramic liners could be retrieved. Both showed black staining in the postero-superior portion of the rim. The outer edge of the bearing surface of the retrieved acetabular liners was evaluated with SEM. The black stained area of the acetabular liner rim was found to be roughened. A micro-crack propagating into the deep portion of the ceramic liner was observed in one liner.

Our observations suggest that impingement between the ceramic liner and the metal neck can cause crack formation leading to ceramic liner failure in vivo.

Wound complication including superficial infection is a concern after total knee arthroplasties (TKA) in diabetics. However, influence of glycoregulation before TKA has not been investigated in relationship to wound healing. Our hypothesis was that glycated hemoglobin (HbA1C), since it reflects long-term regulation of blood glucose, might be associated with incidence of wound complications after TKA in diabetic patients.

We retrospectively reviewed 167 TKAs performed in 115 patients with diabetes mellitus between January 2001 and March 2007. All patients were diagnosed as type II DM and osteoarthritis. A wound complication was defined as a hematoma, bulla, drainage or superficial infection. Stepwise multivariate logistic regression was used to identify which variables had a significant effect on the risk of wound complications. Variables considered were age, gender, body mass index, histories of previous knee surgery, comorbidities, duration of diabetes, the methods of diabetes treatment, complications of diabetes, preoperative HbA1c level, operation time, antibiotics-impregnated cement use, the amount of blood transfusion, and postoperative blood glucose level.

The overall incidence of wound complications was 6.6% (n=11) including superficial infection in 1.8% (n=3), hematoma or bullae in 3.6% (n=6), and drainage in 1.8% (n=3). There were seven cases (4.2%) of deep infection. A multivariate logistic regression revealed that independent risk factors for the development of wound complications were preoperative HbA1C ≥ 8% (odds ratio 6.074, 95% confidence interval 1.119–32.971) and operation time (odds ratio 1.013, 95% confidence interval 1.000–1.026).

Poorly controlled hyperglycemia before surgery may increase the incidence of wound complications among diabetic patients receiving total knee arthroplasties. The correlation of glycemic control and wound complications may assist in the preoperative evaluation and selection of time for surgery.