Background: The use of computer-assisted navigation system had proved to result in consistently accurate alignment of prosthesis in total knee arthroplasty (TKA), however, the clinical midterm to long-term results remains unclear. The objective of this study is to investigate whether clinical results after computer-assisted TKA is superior to the conventional surgical method at midterm, minimum for 5 years follow-up.

Materials: From October 2002 to May 2003, we implanted 30 posterior stabilized total knee prostheses (PFC Sigma; DePuy Inc) using a computed tomography-free navigation system (Vector Vision) for patients diagnosed as osteoarthritis. A control group of 30 matched total knee prostheses of the same type were implanted via a classical, surgeon-controlled technique. Midterm 5 year clinical results including range of motion and Knee Society Clinical Rating Score were compared with these groups. The navigation group was comprised of 23 women and 4 men with a mean age of 81.0 years (range: 56–89 years) at final follow-up and the manual group was comprised of 23 women and 4 men with a mean age of 78.2 years (range: 51–87 years).The results were analyzed statistically and differences of p < 0.05 were considered statistically significant.

Results: Mean follow-up duration was 68.9 months (range: 60–78 months) in the navigation group and 72.8 months (range: 60–80 months) in the manual group. Total 6 patients (3 patients in each group) were lost to follow-up because of their death or lost contact. The follow-up rate was 90 %. No revision or reoperations were required in this study. The average preoperative knee society knee score (KSS) and knee society functional score (KSFS) in the navigation group were 52.9 points (range: 43–77 points) and 51.4 points (range: 25–80 points), respectively and the average postoperative scores were 89.7 points (range: 64–100 points) and 79.7 points (range: 40–100 points), respectively. The average preoperative KSS and KSFS in the manual group were 50.7 points (range: 43–77 points) and 50.3 points (range: 10–80 points), respectively, and the average postoperative scores were 89.6 points (range: 70–100 points) and 75.2 (range: 5–100 points), respectively. No significant differences were noted between the two groups both pre-and postoperatively. The average preoperative range of motion (ROM) in the navigation group was 105.0° (75°–125°); −8.6° (range: 0° to −25°) for extension and 113.6° (range: 85°–135°) for flexion, respectively. The average postoperative ROM was 113.8° (85°–130°); −1.0° (range: 0° to −10°) for extension and 117.0° (range: 105°–130°) for flexion, respectively. The average preoperative ROM in the manual group was 102.5° (65°–140°); −10.2° (range: 0° to −25°) for extension and 112.7° (range: 75°–140°) for flexion, respectively, the average postoperative ROM was 106.9° (80°–130°); −0.0° (range: 0°) for extension and 106.9° (range: 80°–130°) for flexion, respectively. Although no significant difference was found between preoperative ROM for the two groups, the navigation group showed a significantly better ROM compared to the manual group.

Conclusions: Minimum 5-year follow-up of computer-assisted TKA used in the present study revealed that better ROM was achieved, compared with the conventional surgical method. KSS and KSFS were equally good among these two groups. The results focused on the radiographically malaligned patients and further longer follow-up were needed to reveal whether computer-assisted TKA has true clinical benefits compared with the conventional surgical method.

Purpose: Continuous femoral nerve block (CFNB) has been revealed to be a safe and effective method to decrease postoperative pain after total knee arthroplasty (TKA).

However, optimal duration for CFNB to decrease pain and accelerate rehabilitation program after TKA has not been addressed. We, therefore, compared three groups of patients which had different duration of CFNB (0, 2, and 5days) in this study.

Methods: Sixty patients who received primary TKA for osteoarthritis were divided into three groups based on the duration to receive CFNB for 0day, 2days or 5days (twenty patients for each group). Ropivacaine 2mg/mL was given through the femoral nerve catheter using elastomeric infusers (delivering 2ml/hr for each group).

Outcomes including visual analog scale (VAS) pain scores and range of motion (ROM) were compared at 1st, 3rd, 6th, 14th and 21th days after surgery. In addition, the postoperative date when patients could walk stably with parallel bar, walker, or T-cane were recorded and compared.

Results: At 1st and 3rd day postoperatively, the VAS was significantly better in the CFNB 2 days and CFNB 5 days group than in the CFNB 0 day group (P< 0.05).

ROM did not show significant difference among the three groups over postoperative days 1st to 21st (P> 0.05), although groups with the CFNB showed greater ROM at all time points. The CFNB 5 days group obtained stable walking ability with T-cane earlier than other groups (P< 0.05). No patient had any side effect by having CFNB in this study.

Discussion: Postoperative use of CFNB reduced pain at first 3days, and shorten the time to acquire stable walking ability after TKA. We conclude that CFNB should be kept for 5days after surgery to decrease pain and accelerate rehabilitation program after TKA.

We treated 31 patients aged 65 years or more with cervical spondylotic myelopathy by microsurgical decompression and fusion at a single most appropriate level, in spite of MRI evidence of compression at several levels. Spinal cord potentials evoked at operation localised the level responsible for the principal lesion at C3-4 in 18 patients, C4-5 in 11 and at C5-6 in two. Despite the frequent coexistence of other age-related conditions, impairing ability to walk, the average Nurick grade improved from 3.5 before operation to 2.2 at a mean follow-up of 48 months. There was also good recovery of finger dexterity and sensitivity.

Operation at a single optimal level, as opposed to several, has the advantage of minimising complications, of particular importance in this age group.