Takashi Shitama

L-shaped caliper for limb length measurement during total hip arthroplasty

The existing methods of assessing limb lengthening during total hip arthroplasty (THA) are prone to error because the measurements are not parallel to the limb lengthening axis. In order to address this, we designed a caliper to estimate limb lengthening during THA and evaluated its accuracy compared with our previous device, the straight caliper. Limb lengths were measured in 100 patients. The L-shaped caliper was used in 50 cases and the straight caliper in 50. The correlation between intra-operative and post-operative radiographic measurements was significantly improved using the L-shaped device (p < 0.0001, r = 0.934). This method was extremely accurate in predicting changes in limb length due to surgery.

A comparative study of surgical invasion in arthroscopic and open rotator cuff repair

SUMMARY This study investigated the degrees of surgical invasion for arthroscopic rotator cuff repair and open rotator cuff repair by evaluating the serum levels of C-reactive protein, hemoglobin, and interleukin-6. The study participants were 17 patients (group A) who underwent arthroscopic rotator cuff repair and 15 patients (group O) who underwent open rotator cuff repair by the same surgeon. The difference in the size of the rotator cuff tear between the 2 groups was not significant (P > .05). No significant differences were recorded in the postoperative serum levels of C-reactive protein and hemoglobin between the 2 groups (P > .05). The mean postoperative serum level of interleukin-6 was significantly lower in group A than in group O (P < .01). Our findings indicate that arthroscopic rotator cuff repair is less invasive than open rotator cuff repair.

Acetabular cysts heal after successful periacetabular osteotomy

The presence of subchondral bone cysts reflects degeneration or defects of the articular cartilage and elevated local stresses in the subchondral bone. We asked whether the presence of acetabular cysts deleteriously influenced the clinical and radiographic results of periacetabular osteotomy for treatment of dysplastic hips. We retrospectively reviewed 46 hips in 43 patients with cartilage narrowing who had periacetabular osteotomies. Of the 46 hips, 21 had acetabular cysts (cyst group) and 25 did not (control group). The average followups were 5.8 and 5.4 years in the cyst and control groups, respectively. We compared the Harris hip score and coverage of the femoral head between the two groups. The clinical results were similar between the two groups. There were no differences in radiographic evaluations between the two groups at the latest followup. In the cyst group, complete or partial healing of the cysts was observed in 17 of the 21 hips. A postoperative increase in the center-edge angle of 20° or greater was found in 14 of the 17 hips. The preoperative presence of acetabular cysts did not influence the results of periacetabular osteotomy. Adequate rotation of the acetabular fragment induced cyst remodeling.Level of Evidence: Level III, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Effects of the lateral approach on blood flow of the gluteus medius and abductor function in total hip arthroplasty.

Total hip arthroplasty was performed in 19 patients using the lateral approach. Laser Doppler flowmetry was used to measure the blood flow in the anterior and posterior parts of the gluteus medius. The anterior part was split and detached. The posterior part was left intact. The blood flow in the gluteus medius of the anterior part was decreased by 15.4%, while that of the posterior part remained constant during surgery. Postoperatively, the Trendelenburg sign remained positive in 3 of 16 patients. No correlations were observed between a positive Trendelenburg sign and reduction in blood flow of the gluteus medius.