Functional knee phenotypes appear to be more suitable for the Chinese OA population compared with CPAK classification: A study based on 3D CT reconstruction models.

PURPOSE: The aim of this study was to investigate the distribution of coronal plane alignment of the knee (CPAK) classification and functional knee phenotypes in a Chinese osteoarthritis (OA) population and to compare different lower limb alignment targets according to the distribution characteristics to find suitable total knee arthroplasty (TKA) bone cut strategies for the Chinese OA patients. METHODS: The computed tomography (CT) images were retrospectively collected and the three-dimensional (3D) models were reconstructed from 434 Chinese OA patients, including 93 males and 341 females, with a mean age of 66.4 ± 9.3 years. Femoral mechanical angle (FMA), tibial mechanical angle (TMA) and mechanical hip-knee-ankle angle (mHKA) were measured on the 3D models. Arithmetic hip-knee-ankle angle (aHKA) was calculated using FMA plus TMA, and joint line obliquity was calculated as 180 + TMA-FMA. The CPAK according to MacDessi and the functional knee phenotypes according to Hirschmann were performed. In addition, the suitable TKA bone cut strategies were explored according to the phenotypes and based on the characteristics of different alignment targets, such as mechanical alignment, anatomic alignment (AA), kinematic alignment, restricted KA (rKA) and adjusted MA (aMA). Statistical differences were determined using the independent-samples t-test or the two independent-samples Wilcoxon test, with p < 0.05 considered statistically significant. RESULTS: The Chinese OA population showed a varus alignment tendency (mHKA = 172.1° ± 7.2°), to which the TMA was a major contributor (TMA = 84.7° ± 4.4° vs. FMA = 91.3° ± 3.2°). The mHKA was on average 3.9° more varus than the aHKA. A total of 140 functional knee phenotypes were found and 45.6% were concentrated in VARFMA3°-NEUFMA0° to VARTMA3°-NEUTMA0°. More than 70% of patients had different FMA and TMA phenotypes. There were 92.9% of CPAK distributed in types I to IV, with type I accounting for 53.9%. The FMA phenotypes were less changed if the aMA and rKA were chosen, and the TMA phenotypes were less changed if the AA and rKA were chosen. CONCLUSION: Compared with the CPAK, the functional knee phenotypes were more suitable for the Chinese OA population with a wide distribution and a varus tendency, and it seemed more appropriate to choose aMA and rKA as TKA alignment targets for resection. LEVEL OF EVIDENCE: Level Ⅲ.

[Effectiveness of Extracorporeal Shockwave Therapy in Treating Superior Lateral Brachial Cutaneous Nerve Compression Syndrome].

Objective To evaluate the effectiveness of radial extracorporeal shockwave therapy(rESWT) for the treatment of superior lateral brachial cutaneous nerve(SLBCN) compression syndrome.Methods A total of 40 patients with SLBCN compression syndrome who were treated in our department from March 2013 to October 2015 were equally randomized into two groups according to random number table:rESWT group(treated with rESWT for 1 cycle) and control group(treated with local hormone injection for 1 cycle). Visual analogue scale(VAS) and Constant-Murley scale(CMS) were applied to evaluate the shoulder joint function before treatment and 1 month and 1 year after treatment. Results The average CMS scores were(66.7±0.9) and(65.7±1.1)scores in rESWT group and control group,respectively,before treatment(t=0.67,P=0.510) and were(86.9±1.0) and(86.4±1.1)scores one month after treatment(t=0.35,P=0.730);it increased to(89.7±0.7) scores in rESWT group one year later,which was significantly higher than that in control group[(85.3±0.8)scores](t=3.56,P=0.002). The improvement rate was 95% in rESWT group and only 75% in control group. Before treatment,the median VAS score in rESWT group and control group were 5.00(5.00,6.00) and 5.00(4.00,5.75)scores(u=1.13,P=0.29);one month after treatment,the median VAS score in these two groups were 2(1.00,2.75) and 2.00(1.00,2.00)scores(u=0.04,P=0.85);one year later,it was 1.00(0.00,1.00) scores in rESWT group,significantly lower than that in [2.00(1.00,2.00)scores] control group(u=5.09,P=0.02). Conclusion Compared with local hormone injection,rESWT can remarkably alleviate pain and restore shoulder joint function in patients with SLBCN compression syndrome after one year of treatment.