Our institution targets five days of postoperative care prior to discharge after unilateral total knee arthroplasty (TKA). We investigated the causes of prolonged hospital stays and risk factors that may predict prolonged hospitalization. The medical records of 136 patients (21 males, 115 females) who had undergone unilateral TKA from April 2013 to March 2014 were retrospectively reviewed in this study.

　Factors investigated included age, height, weight, total serum protein level, cohabitation status, hospitalization history (i.e. surgical operations, diseases of the central nervous system, etc.), preoperative passive knee flexion and extension range of motion (ROM), preoperative knee extension muscle strength (Weight Bearing Index: WBI), preoperative pain, preoperative Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC), operative time, and knee passive ROM at discharge. Statistical analyses were conducted using multiple logistic regression analysis. The average postoperative hospital stay was 5.1 (±0.4) days. One-hundred and seventeen patients (86%) could be discharged within five postoperative days, whereas 19 patients (14%) could not.

　The multiple logistic regression analysis revealed that hospitalization history, preoperative ROM of knee extension on the operative side, preoperative ROM of knee extension on the non-operative side, preoperative WBI on the operative side, pain while walking on the non-operative side, and operative times were related to prolonged hospital stays. The results suggest that improvement of preoperative WBI for the operative side, knee extension ROM on both the operative and non-operative sides, and reducing knee pain on the non-operative side could improve the clinical pathway after unilateral TKA.

　Bisphosphonates and antiresorptive medications have been widely used for the treatment of multiple myeloma bone diseases, and bone metastasis of solid cancers. Many cases of bisphosphonate and antiresorptive medication related osteonecrosis of the jaw (ONJ) have been reported in Japan. The departments of Medicine and Dentistry had been directed to collaborate on the prevention and treatment of ONJ. We decided to manage the prevention and treatment of ONJ in collaboration with medical doctors, dentists and local dental clinics. In order to promote cooperation between the departments and local dental clinics, we developed a liaison-clinical pathway to enable regional cooperation and simplify responsibilities and information sharing among the collaborating entities. Before implementing the liaison-clinical pathway, a dentist is required to orally screen a patient based on a medical doctor’s request. The actual oral management and ONJ prevention measures are then performed by a local dental clinic. We had applied the liaison-clinical pathway to 11 patients by November 2015, two of whom developed ONJ.

　The liaison-clinical pathway enables the sharing of patient information, facilitating collaboration between hospitals and local dental clinics for the prevention and treatment of ONJ. However, information sharing and ONJ prevention methods must be improved.