Preoperative valgus-corrected hip-knee-ankle angle and medial meniscal extrusion are useful for evaluating postoperative alignment in mobile-bearing UKA.

Purpose: The purposes of the study were to analyze the correlation between preoperative variables (valgus corrected hip-knee-ankle angle (vcHKA), medial osteophyte areas of the tibia and femur, and medial meniscus extrusion (MME)) and the postoperative alignment in mobile-bearing unicompartmental knee arthroplasty (UKA). Methods: This study enrolled 109 patients (118 knees) who underwent mobile-bearing UKA between January 1, 2019 and January 1, 2023, retrospectively. Radiographic parameters, including the HKA, hip-knee-shaft angle (HKS), and valgus-corrected femorotibial angle (vcFTA), were measured using preoperative radiographs. The vcHKA was calculated as vcFTA - HKS. The medial osteophyte areas of the tibia and femur and MME were measured using knee magnetic resonance imaging (MRI). Simple and multiple linear regression analyses, univariate and multivariate logistic regression analyses, and receiver operating characteristic (ROC) curves were performed. Results: In total, 109 patients (118 knees) were enrolled in this study. In the multiple linear regression analysis, vcHKA (ß = 0.732, 95 % confidence interval (95%CI) = 0.582 to 0.881; p < 0.001) and MME (ß = 0.203, 95%CI = 0.001 to 0.405; p = 0.049) were positively correlated with postoperative HKA, and postoperative HKA was modeled according to the following equation: 45.420 + (0.732° * vcHKA) + (0.203 mm × MME). In the multivariate logistic regression analysis, vcHKA (odds ratio (OR) = 2.007, 95 % CI = 1.433 to 2.810, p < 0.001) was associated with postoperative valgus malalignment independently. In the ROC curve, vcHKA (cutoff value: 180°) was predictive of postoperative valgus malalignment, with an accuracy (95%CI) of 0.862 (0.780-0.944). Conclusion: Overcorrection of a varus knee under valgus stress radiograph (VSR) and excessive MME on preoperative MRI increase the possibility of overcorrection of postoperative alignment in mobile-bearing UKA.

Minimally invasive small incision surgical technique for unicompartmental knee arthroplasty.

PURPOSE: It is always a challenge for orthopaedic surgeons to minimise surgical incisions while ensuring excellent surgical results. We propose the minimally invasive small incision (MISI) technique and an extramedullary positioning technique in the unicompartmental knee arthroplasty (UKA) surgery. This study aimed to clarify the early postoperative clinical outcomes and component alignment between MISI and conventional minimally invasive surgical (MIS) techniques. METHODS: We prospectively enrolled 60 patients who underwent MISI-UKA and 60 patients who underwent MIS-UKA as controls. Clinical parameters include the time of straight leg raising, postoperative walking time with walker assistance, hospital stay, Numerical Rating Scale (NRS) pain score and Knee Society Score (KSS). The postoperative components and lower extremity alignment were compared between the two groups with radiographic image measurement. RESULTS: The MISI group obtained a smaller incision during knee extension (P < 0.001) but a longer tourniquet usage time than the MIS group. The MISI group lost less blood (P < 0.001). The MISI group achieved straight leg raising and walking with aid earlier after surgery, with a shorter hospital stay than the MIS group (P < 0.001). Range of motion (ROM), NRS and KSS scores revealed no significant difference between the two groups in six months postoperative follow-up (P > 0.05). Radiographic measurement results between the two groups revealed no statistical difference (P > 0.05) CONCLUSION: The MISI-UKA could achieve faster earlier recovery after surgery and shorter hospital stays without compromising the principles of proper prosthesis position and limb alignment compared with the conventional MIS-UKA.

Intraoperative sensor technology quantifies inter-prosthesis pressure for predicting lower limb alignment after Oxford unicompartmental knee arthroplasty.

Purpose: The aim of this study is to quantify inter-prosthetic pressures at different knee angles in Oxford unicompartmental knee arthroplasty (OUKA) and its correlation with postoperative lower limb alignment. Methods: This study included 101 patients (122 knees) who underwent OUKA from March 2022 to July 2022. The previously designed matrix flexible force sensor was used to measure the inter-prosthesis pressure of different knee joint angles during the UKA operation, and the force variation trend and gap balance difference were obtained. The correlation between inter-prosthesis pressure and postoperative lower limb alignment index including hip-knee-ankle angle (HKAA) and posterior tibial slope (PTS) was analyzed. The effect of PTS change (ΔPTS) on the inter-prosthesis pressure and the range of motion (ROM) of the knee joint was analyzed. Radiographic and short-term clinical outcomes of included patients were assessed. Results: The inter-prosthesis pressure of the different knee joint angles during the operation was not consistent. The mean inter-prosthesis pressure and gap balance difference were 73.68.28 ± 41.65N and 36.48 ± 20.58N. The inter-prosthesis pressure at 0° and 20° was positively correlated with postoperative HKAA (p < 0.001). ΔPTS was positively correlated with the pressure at the end of knee extension and negatively correlated with the pressure at the end of knee flexion (p < 0.001). The HKAA, ROM, degree of fixed knee flexion deformity, and knee society score of the included patients were significantly improved compared with those before the operation (p < 0.001). Conclusion: The inter-prosthesis pressure measured at the knee extension position can predict postoperative HKAA to some degree. Changes in PTS will affect the inter-prosthesis pressure at the end of flexion and end of knee extension, but this change is not related to the range of motion of the knee joint.

Lateral meniscus with tears or with histologic calcification does not increase the risk of lateral osteoarthritis after medial unicompartmental arthroplasty.

PURPOSE: Meniscal tears or histological meniscal calcifications (in the absence of radiological chondrocalcinosis) are frequent in osteoarthritis. Whether lateral meniscal lesions influence clinical outcomes after medial unicompartmental knee arthroplasty (UKA) is unknown. METHODS: We analyzed 130 patients (130 knees) with medial unicompartmental knee arthroplasties between 2005 and 2015. These 130 knees had full articular cartilage thickness in the lateral compartment and no radiological chondrocalcinosis on preoperative radiographs. The lateral meniscus was analyzed with preoperative MRI and a biopsy of the anterior horn at the time of surgery. Synovial fluid was collected and analyzed for calcium pyrophosphate dihydrate crystal deposition (CPPD crystals). Lateral meniscal tears were untreated when detected on MRI or during surgery, with the hypothesis that these tears on the opposite compartment would remain asymptomatic in medial UKA. At average 10-year follow-up, patients were evaluated with clinical and radiographic outcome, with a focus on the risk of joint space narrowing of the lateral femorotibial compartment. RESULTS: CPPD crystals were present in the synovial fluid of 70 knees. Lateral meniscal tears were seen on MRI in 34 (49%) normal meniscuses of the 60 knees without CPPD crystals and in six other knees without histological meniscal calcification despite CPPD crystals. Histological calcification was present on 61 lateral meniscuses with 53 meniscal tears. The results showed no significant differences in the clinical outcomes between knees with lateral meniscal tears or lateral meniscal histological chondrocalcinosis or both lesions and those without these conditions. Additionally, radiographic progression of osteoarthritis in the opposite femorotibial compartment of the knee was not more frequent in patients with these meniscal issues. The ten year cumulative survival rates, measured by the need for total knee arthroplasty, were 91% for knees without meniscal lesions and 92% for knees with these lesions. CONCLUSION: On this basis, treatment of meniscal tears of the lateral compartment and routine aspiration of the knee to assess for birefringent crystals in the planning of medial UKA do not appear necessary.

Predicting valgus malalignment after mobile-bearing UKA using a new method: the arithmetic HKA of the arthritic knee.

BACKGROUND: Valgus malalignment is one of the most common reasons for the progression of osteoarthritis in the lateral compartment of the knee after mobile-bearing unicompartmental knee arthroplasty (UKA). The arithmetic hip-knee-ankle angle (aHKA) of the Coronal Plane Alignment of the Knee (CPAK) classification could reflect the constitutional alignment of the arthritic knee. The purpose of this study was to observe the relationship between the aHKA and valgus malalignment after mobile-bearing UKA. METHODS: This retrospective study was conducted using 200 knees undergoing UKA from January 1, 2019, to August 1, 2022. These radiographic signs, including preoperative hip-knee-ankle angle (HKA), mechanical proximal tibial angle (MPTA), mechanical lateral distal femoral angle (LDFA), and postoperative HKA, were measured using standardized weight-bearing long-leg radiographs. Patients with postoperative HKA > 180° and postoperative HKA ≤ 180° were classified as the valgus group and non-valgus group, respectively. The aHKA was calculated as 180° + MPTA - LDFA in this study, which had the same meaning as that (aHKA = MPTA - LDFA) in the CPAK classification. The Spearman correlation analysis, the Mann-Whitney U test, the chi-square test, the Fisher's exact test, and multiple logistic regression were used in the study. RESULTS: Of the 200 knees included in our study, 28 knees were classified as the valgus group, while 172 knees were in the non-valgus group. The mean ± standard deviation (SD) of aHKA (all groups) was 177.04 ± 2.58°. In the valgus group, 11 knees (39.3%) had a value of aHKA > 180°, while 17 knees (60.7%) had a value of aHKA ≤ 180°. In the non-valgus group, 12 knees (7.0%) had a value of aHKA > 180°, while 160 knees (93.0%) had a value of aHKA ≤ 180°. In Spearman correlation analysis, aHKA was positively correlated with postoperative HKA (r = 0.693, p < 0.001). In univariate analysis, preoperative HKA (p < 0.001), LDFA (p = 0.02), MPTA (p < 0.001), and aHKA (p < 0.001) showed significant differences between the valgus and non-valgus groups. Variables with p < 0.1 in univariate analysis were further analyzed using multiple logistic regression analysis, and the variable-aHKA (> 180° vs ≤ 180°, odds ratio (OR) = 5.899, 95% confidence interval (CI) = 1.213 to 28.686, and p = 0.028) was expressed as the risk factor of postoperative valgus malalignment. CONCLUSION: The aHKA is correlated with the postoperative alignment of mobile-bearing UKA and a high aHKA (> 180°) will increase the risk of postoperative valgus malalignment. Therefore, mobile-bearing UKA should be performed with caution in patients with preoperative aHKA > 180°.

Subchondral Bone Plate Classification: A New and More Sensitive Approach for Predicting the Prognosis of Osteonecrosis of the Femoral Head.

BACKGROUND: This study explores the impact of subchondral bone plate necrosis on the development of the osteonecrosis of femoral head (ONFH) and its joint collapse. METHODS: This retrospective study included 76 ONFH patients (89 consecutive hips) with Association for Research on Osseous Circulation stage II who received conservative treatment without surgical intervention. The mean follow-up time was 15.60 ± 12.29 months. ONFH was divided into 2 types (I and II): Type I with a necrotic lesion involving subchondral bone plate and Type II with a necrotic lesion not involving subchondral bone plate. The radiological evaluations were based on plain x-rays. The data were analyzed using SPSS 26.0 statistical software. RESULTS: The collapse rate in Type I ONFH was significantly higher than that in Type II ONFH (P < 0.001). The survival time of hips with Type I ONFH was significantly shorter than those with Type II ONFH and with the endpoint of the femoral head collapse (P < 0.001). The collapse rate of Type I in the new classification (80.95%) was higher compared with that of the China-Japan Friendship Hospital (CJFH) classification (63.64%), and the difference was statistically significant (χ2 = 1.776, P = 0.024). CONCLUSION: Subchondral bone plate necrosis is an important factor that affects ONFH collapse and prognosis. Current classification using subchondral bone plate necrosis is more sensitive for predicting collapse compared with the CJFH classification. Effective treatments should be taken to prevent collapse if ONFH necrotic lesions involve the subchondral bone plate.

Gap balance difference of unicompartmental knee arthroplasty between hanging leg and supine leg position: a prospective cohort study.

PURPOSE: Gap balance is critical in Oxford unicompartmental knee arthroplasty (OUKA) surgery; the effect of lower limb positioning on gap balance judgements has not been reported. There are two mean operative positions for OUKA patients, the hanging leg (HL) and the supine leg (SL) position. This study aimed to investigate the gap balance achieved by current UKA surgical techniques by using a force sensor, to compare the differences in gap balance between the two different positions, and to test whether the difference in gap balance leads to different outcomes in terms of component alignment and early post-operative clinical outcomes. METHODS: This prospective study included 97 knees (76 patients), who underwent OUKA from June 1, 2020, to July 31, 2021, of which 67 knees underwent UKA in the supine leg position and the other 30 in the hanging leg position. When the operator was satisfied with the gap balance, the contact forces between the trial and the spacer block were measured at 90° of knee flexion (flexion gap) and 20° of knee flexion (extension gap) using a pre-developed matrix flexible force sensor. X-rays were reviewed three to five days after surgery. Knee Society Scores (KSS) were obtained at the six month follow-up. RESULTS: Compared to the HL group, the contact force at the flexion gap was higher in the SL group: 55.15N (SD 43.36N) vs. 34.25N (SD 27.56N) (p < 0.05), whereas in the extension gap, there was no significant difference, 90.19 N (SD 43.36N) in the SL group and 86.72N (SD 43.08N) in the HL group (ns.). The contact force was greater in the extension gap than in the flexion gap in both groups (p < 0.01). The gap balance difference in the HL group was 52.46N (SD 31.33N), which was greater than that of the SL group at 35.03N (SD 19.50N) (p < 0.05). There were no significant differences in component alignment or lower limb mechanical alignment between the two groups. There was no significant difference in pre-operative and post-operative KSS between the two groups, while post-operative KSS was significantly higher in both groups compared to the pre-operative period. CONCLUSION: The intra-operative contact forces between the flexion and extension gaps differed in the two groups; the hanging leg position appeared to produce a greater difference in the judgement of gap balance than the supine leg position, but this difference did not adversely affect the alignment of the component or the early post-operative clinical outcome.

Coronal tibiofemoral subluxation under valgus stress force radiography is useful for evaluating postoperative coronal tibiofemoral subluxation in mobile-bearing UKA.

PURPOSE: Coronal tibiofemoral subluxation (CTFS) is considered a controversial and potential contraindication to unicompartmental knee arthroplasty (UKA) but is less discussed. The study aims to observe the CTFS in a cohort of patients before and after mobile-bearing UKA and to investigate the relationship between preoperative variables (preoperative CTFS and preoperative CTFS under valgus stress) and postoperative CTFS after mobile-bearing UKA. METHODS: The study retrospectively analyzed 181 patients (224 knees) undergoing mobile-bearing UKA from September 1 2019 to December 31 2021. By using hip-to-ankle anterior-posterior (AP) standing radiographs and valgus stress force radiographs, preoperative CTFS, preoperative CTFS under valgus stress, and postoperative CTFS were measured. CTFS was defined as the distance between the tangent line to the outermost joint edge of the lateral condyle of the femur and the tangent line of the lateral tibial plateau. All patients were divided into two groups based on postoperative CTFS, group A (postoperative CTFS ≤ 5 mm) and group B (postoperative CTFS > 5 mm). The Student's t-test, one-way ANOVA together with Tukey's post hoc test, the chi-square test, the Fisher's exact test, Pearson correlation analysis, simple and multiple linear regression, and univariate and multiple logistic regression were used in the analyses. RESULTS: The means ± standard deviations (SD) of preoperative CTFS, preoperative CTFS under valgus stress, and postoperative CTFS were 4.96 ± 1.82 mm, 3.06 ± 1.37 mm, and 3.19 ± 1.27 mm. The difference between preoperative CTFS and postoperative CTFS was statistically significant (p < 0.001). The preoperative CTFS (6.35 ± 1.34 mm) in Group B (n = 22) was significantly higher than that (4.81 ± 1.82 mm) in Group A (n = 202) (p < 0.001), so was the variable-preoperative CTFS under valgus stress (5.41 ± 1.00 mm (Group B) > 2.80 ± 1.14 mm (Group A), p < 0.001). In Pearson correlation analysis, there was a correlation between preoperative CTFS and postoperative CTFS (r = 0.493, p < 0.001), while the correlation between preoperative CTFS under valgus stress and postoperative CTFS was stronger (r = 0.842, p < 0.001). In multiple linear regression analysis, preoperative CTFS under valgus stress (ß = 0.798, 95% confidence interval (CI) = 0.714-0.883, p < 0.001) was significantly correlated with postoperative CTFS. In multiple logistic regression analysis, preoperative CTFS under valgus stress (OR = 12.412, 95% CI = 4.757-32.384, and p < 0.001) was expressed as the risk factor of postoperative CTFS (> 5 mm). CONCLUSION: Preoperative CTFS can be improved significantly after mobile-bearing UKA. In addition, postoperative CTFS is correlated with preoperative CTFS under valgus stress and a higher preoperative CTFS under valgus stress will increase the risk of higher postoperative CTFS (> 5 mm). LEVEL OF EVIDENCE: Level III.

Clinical and radiological outcomes of jumbo cup in revision total hip arthroplasty: A systematic review.

Introduction: Many studies have reported the clinical outcomes of a jumbo cup in revision total hip arthroplasty (rTHA) with acetabular bone defect. We conducted a systematic review to access the survivorship and clinical and radiological outcomes of a jumbo cup in rTHA. Methods: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive literature search from PubMed, MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews was performed with the keywords ("revision" OR "revision surgery" OR "revision arthroplasty") AND ("total hip arthroplasty" OR "total hip replacement" OR "THA" OR "THR") AND ("jumbo cup" OR "jumbo component" OR "extra-large cup" OR "extra-large component"). Studies reporting the clinical or radiological outcomes were included. The basic information and radiological and clinical results of these studies were extracted and summarized for analysis. Results: A total of 19 articles were included in the systematic review. The analysis of clinical results included 953 hips in 14 studies. The re-revision-free survivorship of the jumbo cup was 95.0% at a mean follow-up of 9.3 years. Dislocation, aseptic loosening, and periprosthetic joint infection were the top three complications with an incidence of 5.9%, 3.0%, and 2.1%, respectively. The postrevision hip center was relatively elevated 10.3 mm on average; the mean postoperative leg-length discrepancy was 5.4 mm. Conclusion: A jumbo cup is a favorable option for acetabular bone defect reconstruction in rTHA with satisfying survivorship and acceptable complication rates.

Sensor Assessment of Gap Balance in Mobile-Bearing Unicompartmental Knee Arthroplasty.

The most important procedure of mobile-bearing unicompartmental knee arthroplasty (UKA) is to balance the knee flexion and extension gap. Conventionally, the balance was determined by the subjective assessment of plugging out the feeling gauge. Since it mainly depended on the surgeons' experience, the accuracy was always in doubt. In the past 10 years, pressure sensors have been introduced to guide the gap balance in total knee arthroplasty (TKA). However, the sensor technique was introduced to UKA very recently. Herein is our sensor assessment of the gap balance in 20 cases UKA by one experienced surgeon. The sensor was a custom-designed force sensor matrix according to the shape of the tibial trial of mobile-bearing UKA. The postoperative clinical outcomes and radiographic results were recorded for future comparison. We aim to use this method to assess more than 200 cases of UKA by various surgeons to ultimately standardize the gap-balance result.

Practical Strategy to 1,1'-Dideoxygossypol Derivatives from Gossypol and Its Antitumor Activities.

A practical and scalable route for the synthesis of 1,1'-dideoxygossypol from natural polyphenol product gossypol is described. The key step is the successful regioselective deacetylation of hexaacetyl apogossypol 9 and the following reductive removal of hydroxyl groups. The two steps of deacetylation occurred on the different sites under different conditions. The synthetic route follows a simple protection-deprotection strategy, and the yields of each step are over 85%. The total yield of this 9-step synthesis is over 40%, which is much better than the reported total synthesis method. The antitumor results illustrate that 1,1'-hydroxyl groups are not necessary for antitumor activities. In addition, 1,1'-dideoxygossypol has superior aqueous solubility (215 mg/L) compared to gossypol (64 mg/L).

A radiographic model predicting the status of the anterior cruciate ligament in varus knee with osteoarthritis.

PURPOSE: The study aims to investigate the accuracy of different radiographic signs for predicting functional deficiency of anterior cruciate ligament (ACL) and test whether the prediction model constructed by integrating multiple radiographic signs can improve the predictive ability. METHODS: A total number of 122 patients from January 1, 2018, to September 1, 2021, were enrolled in this study. Among them, 96 patients were classified as the ACL-functional (ACLF) group, while 26 patients as the ACL-deficient (ACLD) group after the assessment of magnetic resonance imaging (MRI) and the Lachman's test. Radiographic measurements, including the maximum wear point of the proximal tibia% (MWPPT%), tibial spine sign (TSS), coronal tibiofemoral subluxation (CTFS), hip-knee-ankle angle (HKA), mechanical proximal tibial angle (mPTA), mechanical lateral distal femoral angle (mLDFA) and posterior tibial slope (PTS) were measured using X-rays and compared between ACLF and ACLD group using univariate analysis. Significant variables (p < 0.05) in univariate analysis were further analyzed using multiple logistic regression analysis and a logistic regression model was also constructed by multivariable regression with generalized estimating models. Receiver-operating-characteristic (ROC) curve and area under the curve (AUC) were used to determine the cut-off value and the diagnostic accuracy of radiographic measurements and the logistic regression model. RESULTS: MWPPT% (odds ratio (OR) = 1.383, 95% confidence interval (CI) = 1.193-1.603, p < 0.001), HKA (OR = 1.326, 95%CI = 1.051-1.673, p = 0.017) and PTS (OR = 1.981, 95%CI = 1.207-3.253, p = 0.007) were shown as predictive indicators of ACLD, while age, sex, side, TSS, CTFS, mPTA and mLDFA were not. A predictive model (risk score = -27.147 + [0.342*MWPPT%] + [0.282*HKA] + [0.684*PTS]) of ACLD using the three significant imaging indicators was constructed through multiple logistic regression analysis. The cut-off values of MWPPT%, HKA, PTS and the predictive model were 52.4% (sensitivity:92.3%; specificity:83.3%), 8.5° (sensitivity: 61.5%; specificity: 77.1%), 9.6° (sensitivity: 69.2%; specificity: 78.2%) and 0.1 (sensitivity: 96.2%; specificity: 79.2%) with the AUC (95%CI) values of 0.906 (0.829-0.983), 0.703 (0.574-0.832), 0.740 (0.621-0.860) and 0.949 (0.912-0.986) in the ROC curve. CONCLUSION: MWPPT% (> 52.4%), PTS (> 9.6°), and HKA (> 8.5°) were found to be predictive factors for ACLD, and MWPPT% had the highest sensitivity of the three factors. Therefore, MWPPT% can be used as a screening tool, while the model can be used as a diagnostic tool.

Short-Term Efficacy and Safety of Secukinumab for Ankylosing Spondylitis: A Systematic Review and Meta-Analysis of RCTs.

Secukinumab is a novel IL-17A inhibitor that has been confirmed to be effective for treating PsA and RA. Several studies have demonstrated that secukinumab also provides benefits for AS patients. Thus, we performed a meta-analysis of RCTs to evaluate the short-term efficacy and safety of secukinumab for the management of AS. The PubMed, Medline, Embase, Web of Science, and Cochrane Library databases were searched for RCTs published prior to March 2020 on the treatment of AS with secukinumab. The primary outcome was the ASAS20 response, and the secondary outcomes included the ASAS40 response, ASAS5/6 response, SF-36 PCS score, ASQoL score, and AEs. Dichotomous data were expressed as pooled RRs with 95% CIs, while continuous data were expressed as pooled MDs with 95% CIs. Subgroup analysis was conducted based on whether the AS patients previously underwent treatment with TNFi. A total of 4 RCTs with 1166 patients were included in our meta-analysis. At week 16, secukinumab 150 mg yielded significant improvements in the clinical response and patient-reported outcomes for AS patients. There was no increased risk of AEs. Consistent results were detected in the meta-analysis of secukinumab 75 mg versus a placebo. Furthermore, no significant difference was detected between the secukinumab 75 mg group and secukinumab 150 mg group. We concluded that secukinumab is effective for treating AS and generally well tolerated by AS patients in the short term, regardless of whether they previously underwent TNFi treatment. The superiority of secukinumab 150 mg over secukinumab 75 mg seems to be limited, since no significant difference in any endpoint was detected between the two groups.

The Role of Immune Regulatory Cells in Nontraumatic Osteonecrosis of the Femoral Head: A Retrospective Clinical Study.

The immunologic factors have been implicated in the pathogenesis of osteonecrosis. We aimed to investigate the potential role of immune regulatory cells in the development of osteonecrosis of femoral head (ONFH). Sixty-seven patients diagnosed with ONFH and fifty-eight age-, height-, and weight-matched healthy subjects were included in this retrospective study between September 2015 and September 2018. The flow cytometry was used to test the count, percentage, and ratio of T and B lymphocyte subsets in peripheral blood. The T and B lymphocyte levels were compared among different ARCO stages, CJFH types, and etiology groups. The total lymphocyte count, CD3+T cells, Ts cells (CD3+CD8+), B-1 cell count, and B-1 cells (CD5+CD19+) were significantly higher in the patients with ONFH than those in the control subjects. The percentage of T lymphocytes in the patients with ARCO IV stage was significantly smaller than that in the ONFH patients with ARCO II and III stages. The percentage of inhibitory T lymphocytes in patients with CJFH type L3 was significantly smaller than that in the patients with types L1 and L2. In terms of the different ONFH etiologies, the total lymphocyte count and Ts cells (CD3+CD8+) were significantly lower in the ONFH patients induced by excessive alcohol intake than those in the idiopathic ONFH patients. Our results seem to indicate that immune regulatory cells, such as T and B lymphocytes, play an important role in the pathogenesis of ONFH. The development and progression of ONFH may be associated with immune system imbalance.