Change of joint-line convergence angle should be considered for accurate alignment correction in high tibial osteotomy.

BACKGROUND: The alignment correction after high tibial osteotomy (HTO) is made both by bony correction and soft-tissue correction around the knee. Change of the joint-line convergence angle (JLCA) represents the soft-tissue correction after HTO, which is the angle made by a tangential line between the femoral condyles and the tibial plateau. We described the patterns of JLCA change and related factors after HTO and investigated the appropriate preoperative planning method. METHODS: Eighty patients who underwent HTO between 2013 and 2016 were included for this retrospective study. Standing, whole-limb radiograph, supine knee anteroposterior (AP) and lateral were measured on the preoperative and postoperative radiographs. The patterns of JLCA changes and related factors were analyzed. RESULTS: JLCA decreased by a mean of 0.9° ± 1.2° (P < 0.001) after HTO. Sixteen patients (20%, group II) showed a greater JLCA decrease ≥ 2°, while 64 (80%, group I) patients remained in a narrow range of JLCA change < 2°. Group II showed more varus deformity (varus 8.1° vs. varus 4.7° in the mechanical femorotibial angle, P < 0.001), greater JLCA on standing (4.9° vs. 2.1°, P < 0.001), and the difference of JLCA in the standing and supine positions (2.8° vs. 0.7°, P < 0.001) preoperatively compared to group I. The risk of a greater JLCA decrease ≥ 2° was associated with greater preoperative JLCA in the standing position and the difference between the JLCA in the standing and supine positions. Postoperative JLCA correlated better with preoperative JLCA in the supine position than those in the standing position. A preoperative JLCA ≥ 4° or the difference of preoperative JLCA in the standing and supine positions ≥ 1.7° was the cut-off value to predict a large JLCA decrease ≥ 2° after HTO in the receiver operating characteristic (ROC) curve analysis. CONCLUSIONS: Surgeons should consider the effect of the JLCA change during the preoperative planning and intraoperative procedure to avoid unintended overcorrection.

The effect of interleukin-8 in the early stage after anterior cruciate ligament reconstruction with remnant preservation.

PURPOSE: We studied the effect of interleukin-8 (IL-8) as the factor for angiogenesis in the joint fluid of remnant-preserved anterior cruciate ligament reconstruction (RP-ACLR). MATERIALS AND METHODS: We measured 12 cytokines in joint fluid by multiplex assay and assessed the relationship between IL-8 and vascular endothelial growth factor (VEGF) concentrations. The signal intensity and mean sagittal diameter via postoperative magnetic resonance imaging (MRI) scans were evaluated and the stress X-ray image was analyzed at 3, 6, and 12 months after operation. RESULTS: The IL-8 concentration was highest 3 months postoperatively in those patients who underwent RP-ACLR. Clinical data also showed that the signal intensity and stress radiography of the knee graft were significantly better at the early postoperative stage. DISCUSSION: Our results show that IL-8 plays an important role in angiogenesis within 3 months after RP-ACLR. This effect yields better recovery after operation. RP-ACLR patients with high knee stability in clinical data were identical to those with high expression of IL-8 in experimental data. Therefore, IL-8 has been shown to help revascularization and ligamentization of the grafted tendon. These results indicate that IL-8 in RP-ACLR is an important factor for angiogenesis after operation. Unfortunately, the relationship of IL-8 and VEGF in vivo has not been studied. CONCLUSION: Our results showed that the IL-8 concentration was very high within 3 months after RP-ACLR operation. The increase in concentration of IL-8 over time was consistent with the increase in VEGF concentration. In the IL-8 clinical setting, MRI analysis showed that ACL synovialization and tension were better in patients who underwent the remnant preservation method. In addition, it was shown that RP-ACLR may be advantageous for early anterior stability within 1 year post operation and beneficial for tendon graft in the early stage post operation. Taken together, our findings suggest that IL-8 may contribute to angiogenesis which is helpful for revascularization and ligamentization of the graft tendon in the early stages of RP-ACLR.

Relationship of the Shape of Subacromial Spur and Rotator Cuff Partial Thickness Tear.

BACKGROUND: The present study was undertaken to evaluate the relationship between location of the rotator cuff tear and shape of the subacromial spur. METHODS: Totally, 80 consecutive patients who underwent arthroscopic repair for partial thickness rotator cuff tear were enrolled for the study. Bigliani's type of the acromion, type of subacromial spur, and location of partial thickness tear of the rotator cuff were evaluated using plain X-ray and magnetic resonance imaging. We then compared the groups of no spur with spur, and heel with traction spur. RESULTS: Of the 80 cases, 25 cases comprised the no spur group, and 55 cases comprised the spur group. There was a significant difference in type of tear (p=0.0004) between these two groups. Bursal side tears were significantly greater (odds ratio=6.000, p=0.0007) in the spur group. Subjects belonging to the spur group were further divided into heel (38 cases) and traction spur (17 cases). Comparing these two groups revealed significant differences only in the type of tear (p=0.0001). Furthermore, the heel spur had significantly greater bursal side tear (odds ratio=29.521, p=0.0005) as compared to traction spur. CONCLUSIONS: The heel spur is more associated to bursal side tear than the traction spur, whereas the traction spur associates greater to the articular side tear.

Pediatric Trampoline-Related Injuries in a Nationwide Registry in South Korea, 2011 to 2016.

PURPOSE: Trampoline-related injuries are steadily increasing. To our knowledge, there have been very few studies on trampoline injuries in Asia. The purpose of this study is to report the characteristics of pediatric trampoline injuries in Korea. MATERIALS AND METHODS: We conducted a nationwide retrospective cohort study. Data were collected from prospective nationwide databases (Emergency Department-based Injury In-depth Surveillance databases of the Korea Centers for Disease Control and Prevention) for patients who visited emergency departments (EDs) after injuries during 2011-2016. RESULTS: Of 263712 patients between 0 and 17 years of age, 2799 patients with trampoline injuries visited EDs. The median age of the patients was 5 years (interquartile range, 3-8 years), and 63% of the patients were under 6 years old. Of the patients, 1526 (54.2%) were male. Seventy-six percent of injuries occurred at trampoline parks. Trampoline injuries and trampoline park injuries have increased steadily, while ages at injury have gradually decreased year by year (p<0.001). Injury locations included the lower extremity (47%), head and face (24%), and upper extremity (24%). A fracture was sustained by 886 (31.7%) patients. The distal humerus and proximal tibia were the most common fracture sites (34% and 23%, respectively). Fractures occurred more commonly in trampoline parks than in homes (33.7% vs. 21.1%, p<0.001). CONCLUSION: In Korea, pediatric trampoline injuries and trampoline park injuries have tended to increase, while ages at injury have tended to decrease. Policies to prevent trampoline injuries are needed.