Objective To investigate the relief of low back pain after hip arthroplasty in patients with hip joint and spinal degenerative diseases, and to discuss the effects of unilateral and bilateral hip surgery on the relief of low back pain. Methods In this retrospective study, we followed 153 patients (69 males and 84 females, age: 43–88 years) who had undergone total hip arthroplasty (THA) via a posterolateral approach and also suffered from lumbar degenerative diseases in the period of 2009 to 2019. The inclusion criteria were: (i) patients who had been diagnosed with severe hip degenerative disease and also been diagnosed with lumbar degenerative disease; (ii) patients who had undergone THA surgery; and (iii) patients who were retrospectively recruited. The exclusion criteria were: (i) patients who had undergone lumbar fusion or internal fixation surgery; or (ii) patients who had vascular claudication, history of major trauma, diabetic polyneuropathy, lumbar and pelvic infections, tumor diseases; (iii) or patients who had undergone THA because of femoral neck fracture or ankylosing spondylitis. The improvement of hip joint function and the relief of low back pain (LBP) were studied, and the effect of unilateral and bilateral THA on the relief of LBP were discussed. Hip pain and function were evaluated by the Harris Hip Score (HHS), LBP was evaluated by Visual Analog Scale (VAS), and lumbar function was evaluated by the Japanese Orthopaedic Association (JOA) scoring system. Results The average follow‐up time was 44.3 months (24–108 months). All patients recovered smoothly without complications. The LBP VAS of 153 patients decreased from 4.13 ± 1.37 preoperatively to 1.90 ± 1.44 postoperatively. The average HHS increased from 45.33 ± 13.23 preoperatively to 86.44 ± 7.59 postoperatively at the latest follow‐up. According to Japanese Orthopaedic Association scoring system, the proportion of patients with good response to treatment in these 153 patients reached 93.46%. LBP VAS decreased from 4.18 ± 1.38 preoperatively to 1.95 ± 1.49 postoperatively in unilateral group and from 3.94 ± 1.32 preoperatively to 1.73 ± 1.23 postoperatively in bilateral group, respectively. There were only nine patients with persistent or aggravated LBP after operation. Among them, six patients underwent subsequent lumbar surgery (five patients had pain relieved after reoperation and one patient had not) and the other three patients chose conservative treatment for pain. Conclusion THA can relieve LBP while relieving hip pain and restoring hip function in patients with both hip and lumbar degenerative disease, thus possibly avoiding further spinal surgery.

Objective: Mismatch between the femoral component and the resected surface is related to the postoperative clinical outcome. This study aimed to measure the morphometric features of the distal femoral resected surfaces in patients with osteoarthritis in southwestern China and to compare the measured morphometric data with six commonly used total knee arthroplasty (TKA) femoral components in China. Method:The computer tomography (CT) images of a total of 406 knees from 203 osteoarthritis patients who underwent TKA from January 2018 to December 2021 were imported into Mimics 21.0 software to reconstruct the threedimensional (3D) model of the femur. Morphometric data of the distal femoral resected surfaces were measured after the completion of simulated bone resection in the software. The data included the medial-lateral (ML) dimension, anterior-posterior (AP) dimension, and the aspect ratio (AR) (AR = ML/AP), which were compared between genders with independent sample t-tests. In addition, we plotted the scatter diagram of those morphometric data in Origin software, and the linear fits of ML versus AP and AR versus AP were performed and compared for the six femoral components commonly used in enrolled patients in China. Results:The mean ML dimension, the mean AP dimension, and the mean AR value measured for Chinese knees were 66.62 AE 4.57 mm, 58.10 AE 3.74 mm, and 1.15 AE 0.06 respectively. All dimensions were significantly larger in males than in females, including the calculated values for AR (P < 0.05). The fitted lines for males showed that the ML dimensions tended to be wider compared to femoral components of a given AP dimension. Females tended to have wider ML dimensions compared to small femoral components and, on the other hand, narrower ML dimensions compared to large femoral components. Conclusion:The femoral component of the current commonly used TKA prosthesis in China may not be perfectly matched to the distal femoral resected surface of patients in southwestern China. Male patients tended to underhang in all dimensions of the ML dimension. Female patients with shorter AP lengths are more likely to experience underhang, whereas those with longer AP lengths are more likely to develop overhangs. Therefore, we recommend multiple ML width options for a given AP length to more appropriately match the Chinese femoral anatomy.

This study aimed to determine whether proximal tibiofibular joint (PTFJ) morphology was related to knee alignment in osteoarthritis (OA) patients. Methods: 67 OA patients were enrolled in this study. The morphology of the PTFJ including articular shape type, articular surface area, joint inclination, relative articular height, and joint declination were measured from 3D models. The knee alignment of each subject was characterized as varus, normal, or valgus according to the femorotibial angle (FTA). The FTA was measured on weight-bearing X-rays. Multinomial logistic regression analysis was used to evaluate the association between PTFJ morphology and knee alignment. Results: there were significant differences between varus, valgus, and normal FTA groups in terms of shape type (p = 0.021), inclination of the PTFJ (p = 0.025), relative articular height (p = 0.019), and PTFJ declination angle (p = 0.011). A higher relative articular height (OR: 0.608, 95% CI: 0.205–0.998, and p = 0.017) and lower declination angle (OR: 0.632, 95% CI: 0.601–0.887, and p =0.019) were found to be associated with an increased likelihood of having a valgus FTA rather than a varus FTA. Conclusion: our results indicate that PTFJ morphology is associated with knee alignment.

Objective: The purpose of this study was to assess the association between the flat feet and the symptoms of knee osteoarthritis (OA). Methods: 95 participants with knee osteoarthritis were recruited for this study. Knee osteoarthritis was evaluated using a combination of Kellgren-Lawrence (K-L) grade, femoral-tibial angle (FTA), knee pain and physical function. The Arch Index (AI) was used to assess the severity of flat feet, with subjects being divided into groups with no flat feet, mild flat feet and severe flat feet. A chi-square test, continuous variable t test and Mann-Whitney U test were used to compare differences in K-L grade, knee pain, physical function and femoral-tibial angle. Regression analysis was performed to assess the correlation between the flat feet and the characteristics of knee osteoarthritis. Results: Flat feet was associated with a significantly increased risk of having a larger varus angle (beta: -2.306; 95% confidence interval (CI): -3.703, -0.909; p = 0.001), higher pain score (beta: 0.356; 95% CI: 0.130, 0.582; p = 0.002) and greater loss of physical function (beta: 0.281; 95% CI: 0.071, 0.491; p = 0.009). Severe grades of flat feet were associated with an increased risk of pain (beta: -0.289; 95% CI: -0.543, -0.035; p = 0.026). However, the severity of flat feet was not associated with K-L grade, FTA or physical function. Conclusion: There was a significant association between the presence of flat feet and symptoms of knee OA, and severe flat feet was found to aggravate OA-related knee pain. Active treatment to correct flat feet is recommended to relieve symptoms associated with knee OA. Level of Evidence: Level II