Objective:To compare the short-term clinical outcomes associated with longitudinal outside-in capsulotomy and transverse inside-out capsulotomy in arthroscopic surgery for femoral acetabular impingement (FAI).Methods:A retrospective cohort study was conducted encompassing 30 patients who underwent arthroscopic surgery to address FAI from August 2020 to June 2021. This group, comprising an equal distribution of 15 males and 15 females with a mean age of 40.9±10.7 years (range 15-63 years), was subjected to longitudinal outside-in capsulotomy without subsequent capsular closure. Patients of the longitudinal capsulotomy group (Group L) were 1∶1 matched with another 30 patients who underwentarthroscopic surgery for FAI between April 2018 and April 2019 as controls, including 10 males and 20 females, aged 40.6±9.2 years old (range, 25-60 years old). The control group (Group T) underwent transverse inside-out capsulotomy without capsular closure. The subjective functional outcomes within both groups were meticulously evaluated, including the modified Harris hip score (mHHS) and the visual analog scale (VAS). Additionally, the proportions of subjects achieving Grade A or B classifications and the patient acceptable symptomatic state (PASS) based upon the mHHS were scrupulously calculated.Results:The foundational data, encompassing pre-operative subjective functional scores, pre-operative radiological dimensions, and intra-operative discoveries, showed no significant differences between the groups ( P>0.05). At the one-year follow-up, Group L demonstrated a reduced post-operative VAS score of 1.3±1.6, a diminution from the pre-operative mean of 6.3±1.4, alongside a mHHS improvement from 63.8±15.1 pre-operatively to 93.5±5.1 post-operatively. Conversely, Group T revealed a post-operative VAS score of 1.4±1.5, ameliorated from a pre-operative mean of 7.0±1.6, and an mHHS improvement from 64.6±7.8 pre-operatively to 90.4±8.4 post-operatively. The improvements of VAS and the mHHS showed statistical significance in both groups ( P<0.001), yet no significant disparities were observable in the post-operative VAS and mHHS results between the two cohorts ( t=0.03, P=0.735 for VAS; t=1.75, P=0.082 for mHHS). Remarkably, every participant in Group L achieved Grade A or B in mHHS; however, only 83.3% of Group T attained these grades, a discrepancy manifesting statistical significance (χ 2=8.32, P<0.01). Correlatively, the attainment of PASS stood at 100% in Group L versus 90% in Group T, denoting a statistically significant difference (χ 2=6.54, P<0.01). Conclusion:Longitudinal outside-in capsulotomy in the arthroscopic management of FAI is vindicated as an effective technique, exhibiting parallel clinical outcomes to the traditional transverse inside-out technique.

Objective:To evaluate the clinical outcomes in anterior cruciate ligament (ACL) patients undergoing ACL reconstruction combined with anterolateral ligament (ALL) reconstruction in treating patients with Grade 2 pivot-shift.Methods:From October 2015 to August 2018, a total of 59 patients with Grade 2 pivot shift were allocated into ALL reconstruction group underwent combined ACL and ALL reconstruction ( n=29) and control group underwent isolated ACL reconstruction ( n=30). Lachman, pivot-shift and KT-1000 side-to-side difference test were used to determine the knee laxity. International Knee Documentation Committee (IKDC) subjective score and Lysholm score were used to assess the knee function. The results of Lachman test and pivot-shift test were classified into -, 1+, 2+, 3+. Results:All patients were followed up for 1 year. The average age was 30.5±8.3 years (range, 15-48 years) in ALL reconstruction group with 5 months duration from injury. The left knee was involved in 11 cases, while 18 cases in right knee in ALL reconstruction group. There were 15 cases with injury in medial meniscus and 8 cases in lateral meniscus. In control group, the average age was 32.2±9.7 years (range 17-51 years) with 14 cases in left knees and 16 in right knees. In these patients, 18 of them had medial meniscus injury, while other 11 patients had lateral meniscus injury. The average duration from injury to surgery was 7 months. The Lachman test (-: 25, 1+: 4 vs. -: 25, 1+: 4, Z=-0.91, P=0.361), KT-1000 arthrometer (1.9±1.3 mm vs. 2.2±1.3 mm, t=0.66, P=0.513), IKDC subjective score (92.4±5.6 vs. 90.2±6.7, t=1.37, P=0.176) and Lysholm score (91.0±6.2 vs. 89.1±5.0, t=1.29, P=0.201) did not show significant difference between the two groups. Pivot-shift test (-:27, 1+: 2 vs. -: 20, 1+: 8, 2+: 2, Z=-0.66, P=0.507). Pivot-shift test was significantly superior in ALL reconstruction group compared with that in control group (6.5% vs.33.3%, χ 2=21.70, P<0.001). Conclusion:Patients with preoperative Grade 2 pivot shift had significant improvement in rotatory knee laxity after ACL reconstruction combined with ALL reconstruction compared with isolated ACL reconstruction. However, there was no significant difference in anterior laxity and knee function scores between the two groups.

Objective:To investigate the relationship between anterior tibial translation (ATT) and bony morphology around the knee after anterior cruciate ligament (ACL) injury.Methods:A total of 67 patients diagnosed with acute ACL injury without any meniscal lesions were enrolled in this study between September 2019 and August 2020. Preoperative magnetic resonance imaging (MRI) scans were used to measure the ATT of the lateral compartment, and bony morphology was assessed by measuring lateral femoral condyle (LFC) length, LFC height, lateral tibial plateau (LTP) length, LTP slope and by calculating the following ratios: LFC ratio (LFC length/LFC height), knee extension ratio (LFC length/LTP length), and knee flexion ratio (LFC height/LTP length). The status of the anterolateral ligament (ALL) was assessed by preoperative MRI scans and classified as completely injured (44 patients), partially injured (19 patients), or intact (4 patients). The ATT was compared between patients with completely injured ALL and those with partially injured or intact ALL. Pearson correlation analysis between the ATT and each bony variable was performed in ALL-completely-injured patients and ALL-partially-injured or intact patients.Results:Of the 67 patients, 33 were male and 34 were female, with a mean of age 31.7±9.7 years (range 15-47 years). The average of time interval between ACL injury and MRI examination was 26.0±22.0 days (95% CI: 20.7, 31.4 d). The ATT of the lateral compartment was 5.6±4.0 mm (range, -4.9-16.2 mm), the average of LFC length was 37.3±2.5 mm (range, 30.5-43.2 mm), the average of LFC height was 37.4±3.6 mm (range, 30.6-46.3 mm), the average of LTP length was 46.9±4.1 mm (range, 39.0-56.8 mm), the average of LTP slope was 6.3°±3.1° (range, -3.7°-11.6°), LFC ratio was 100.4%±8.1% (range, 84.1%-119.0%), knee extension ratio was 80.0%±5.8% (range, 66.1%-96.3%), and knee flexion ratio was 80.0%±6.0% (range, 66.4%-93.8%). The ATT was greater in patients with completely injured ALL than in patients with partially injured or intact ALL (6.4±4.3 mm vs. 3.9±2.8 mm, t=2.52, P=0.014). The ATT was negatively correlated with LFC height ( r=-0.43, P<0.001) and LTP length ( r=-0.35, P=0.004) and was positively correlated with LFC ratio ( r=0.48, P<0.001), knee extension ratio ( r=0.36, P=0.003), and LTP slope ( r=0.29, P=0.018). All these correlations were still statistically significant in patients with complete ALL injury ( P<0.05), but were no significant in patients with partial ALL injury or intact ALL ( P>0.05). Conclusion:Bony morphology of the distal femur and proximal tibia was associated with ATT after ACL injury. Such an association was more dramatic in patients with a complete ALL injury.

Objective:To evaluate the outcome of arthroscopic surgical treatment for recalcitrant tennis elbow combined with degenerative lateral ulnar collateral ligament (LUCL) lesions.Methods:A retrospective case series study was made on clinical data of 27 patients with recalcitrant tennis elbow combined with degenerative LUCL lesions admitted to Beijing Jishuitan Hospital from June 2014 to December 2020. There were 19 males and 8 females, with the age range of 39-56 years [(49.8±6.9)years]. The degenerative LUCL lesions were evaluated arthroscopically. Arthroscopic LUCL debridement and shrinkage combined with repair of extensor carpi radialis brevis (ECRB) were performed in all patients. The operation time, intraoperative bleeding volume and length of hospital stay were recorded. The visual analogue scale (VAS), Mayo elbow performance score (MEPS), patient-rated tennis elbow evaluation (PRTEE) scale, and disability of the arm, shoulder and hand (DASH) questionnaire were evaluated and compared preoperatively and at the final follow-up.Results:All patients were followed up for 12-73 months [(24.1±9.7)months], with the operation time of 0.75-1 hours [(0.8±0.2)hours], intraoperative bleeding volume of 5-10 ml [(7.2±1.5)ml], and length of hospital stay of 4-12 days [(6.2±2.1)days]. The VAS, MEPS, PRTEE and DASH scores were significantly improved at postoperative 1 year [1(1,2)points, 95(85,100)points, 8(6,12)points and 12.9(8.9,15.8)points] when compared with those preoperatively [5(3,6)points, 70(65,85)points, 47(42,62)points and 43.8(36.8,49.0)points] (all P<0.01). No patients had limited range of motion, wound infection, heterotopic ossification, traumatic arthritis and other complications. Conclusion:For recalcitrant tennis elbow combined with degenerative LUCL lesions, arthroscopic LUCL debridement and shrinkage combined with ECRB repair can achieve pain relief and elbow function recovery.

Objective:To investigate the short-term clinical outcomes of patients who received combined anterior closing-wedge high tibial osteotomy (ACW-HTO) and anterior cruciate ligament (ACL) reconstruction in treating chronic ACL injury with increased posterior tibial slope (PTS).Methods:From January 2017 to June 2018, a total of 54 patients (46 males and 8 females, mean age 30.8±3.9 years, range from 20 to 42 years) with chronic (time from injury to surgery was more than 6 months) ACL injury and increased PTS (>17°) were retrospectively analyzed. Eighteen of them received combined ACW-HTO and ACL reconstruction (ACW-HTO+ACL reconstruction group), while the remaining 36 received isolated ACL reconstruction (ACL reconstruction group). The demographic data, pre-operative and post-operative anterior tibial translation, pivot-shift result, KT-1000 side-to-side difference, subjective Lysholm score, Tegner activity score, and International Knee Documentation Committee (IKDC) objective grading system were collected and compared between the two groups.Results:There were no significant differences between the two groups in terms of age, sex, body mass index, time from injury to surgery and proportion of patients with concomitant medial or lateral meniscus tear ( P>0.05). At 2-year's follow-up, the anterior tibial translation in the ACW-HTO+ACL reconstruction group was 0.9±0.4 mm, which was significantly smaller than that in the ACL reconstruction group 7.3±1.5 mm ( t=10.049, P<0.001). Moreover, there was significant difference in the pivot-shift result between the two groups (ACW-HTO+ACL reconstruction group: 18 low-grade vs. ACL reconstruction group: 31 low-grade, 5 high-grade) (χ 2=16.071, P<0.001). The KT-1000 side-to-side difference in the ACW-HTO+ACL reconstruction group was 1.5±0.6 mm, which was significantly smaller than that in the ACL reconstruction group 4.4±1.2 mm ( t=13.858, P<0.001). In addition, the subjective Lysholm score in the ACW-HTO+ACL reconstruction group was 93.3±4.3, which was significantly higher than that in the ACL reconstruction group 80.3±6.3 ( t=12.176, P<0.001). The Tegner activity score in the ACW-HTO+ACL reconstruction group was 7.3±0.9, which was significantly higher than that in the ACL reconstruction group 6.8±0.6 ( t=6.356, P=0.043). There was significant difference in terms of the IKDC objective grading system between the two groups (ACW-HTO+ACL reconstruction group: 17 grade A, 1 grade B vs. ACL reconstruction group: 29 grade A, 5 grade B, 2 grade C) (χ 2=12.351, P<0.001). Conclusion:The combined ACW-HTO and ACL reconstruction showed superior short-term knee stability and functional scores compared with the isolated ACL reconstruction in treating chronic ACL injury with increased PTS.

Objective:To evaluate the clinical, radiological and arthroscopic outcomes after surgical repair for chronic lateral meniscus posterior root (LMPR) avulsion combined with anterior cruciate ligament (ACL) reconstruction.Methods:From July 2015 to June 2017, a total of 33 patients who underwent transtibial pull-out suture repair for chronic LMPR avulsion combined with anatomic single-bundle ACL reconstruction with hamstring graft were retrospectively reviewed. There were 30 males and 3 females with an average age of 27.7±7.5 years (range 17-45 years) and a mean BMI of 25.2±3.7 kg/m 2 (range 19.4-36.7 kg/m 2). All patients were available for at least two years of follow-up. A second-look arthroscopy was performed to evaluate the healing status of the repaired meniscus. Subjective knee function was assessed through Lysholm and Tegner scores. Objective knee stability was evaluated using KT-1000 arthrometer side-to-side difference (SSD) and pivot shift test under anesthesia. The tibiofemoral relationship was evaluated by anterior tibial subluxation (ATS) measured on axial MRI. Between patients with preoperative ATS ≥6 mm (18 patients in the ATS positive group) and <6 mm (15 patients in the ATS negative group), the postoperative ATS and the reduction of ATS was also compared. Results:After a mean follow-up of 27.5±4.0 months (range 24-39 months), the LMPR avulsion completely healed in 23 (70%) cases, partially healed in 9 (27%) cases, failed to heal in 1 (3%) case on second-look arthroscopy. The Lysholm score was increased from 60.4±13.6 to 82.7±11.1 at 1 year and to 91.4±9.1 at 2 years operatively ( F=155.996, P<0.001). The Tegner score was increased from 3(2, 5) to 4(3, 5) at 1 year and 6(4, 6) at 2 years postoperatively (χ 2=47.791, P<0.001). The KT-1000 SSD was decreased from 9.1±3.3 mm to 2.0±1.7 mm ( t=11.197, P<0.001). The result of pivot shift test was also improved (10 grade I, 20 grade II, 3 grade III, preoperatively vs 30 grade 0, 3 grade I, postoperatively, U=5.161, P<0.001). The ATS was reduced from 5.7±3.9 mm to 3.5±3.2 mm ( t=3.530, P=0.001). However, there was no statistically significant decrease in the ATS of the ATS negative group ( t=0.400, P=0.695). The ATS of the ATS positive group was reduced from 8.7±1.8 mm to 5.0±3.3 mm ( t=4.765, P<0.001), and the ATS reduction of the ATS positive group was greater than that of the ATS negative group (3.7±3.3 mm vs 0.3±2.8 mm, t=3.115, P=0.004). Conclusion:In patients undergoing ACL reconstruction, the transtibial pull-out suture repair for chronic LMPR avulsion yielded meniscus healing rate of 97% with improved subjective knee function and objective knee stability and better restored the tibiofemoral relationship for patients with excessive ATS.

Objective:To explore the risk factors of primary anterior cruciate ligament (ACL) reconstruction failure.Methods:From November 2015 to May 2017, a total of 178 consecutive patients with clinically diagnosed non-contact ACL injury were treated and followed-up more than 2 years. Twenty-five patients (post-operative failure group) who underwent completely ruptured ACL graft confirmed by MRI, positive pivot-shift test, more than 5 mm side-to-side difference (SSD) measured by KT-1000 arthrometer, more than 5 mm static anterior tibial translation (ATT) measured on MRI were determined to be ACL reconstruction failure. They were matched in a 1∶2 fashion to 50 non-failure patients (post-operative non-failure group), who showed intact ACL graft 2 years after ACL reconstruction. The sex, age, body mass index (BMI), affected side, meniscal injury side, time from injury to surgery, KT-1000 SSD, pivot shift test under anesthesia, follow-up duration, posterior tibial slope (PTS) and ATT measured on the pre-operative weight-bearing whole leg radiographs between the two groups were compared using univariate analysis. Moreover, the predictors of ACL reconstruction failure were assessed by multivariable conditional Logistic regression analysis.Results:Post-operative failure group had a significantly higher PTS and ATT values than those in the post-operative non-failure group (17.21°±2.20° vs 14.36°±2.72°, t=4.395, P<0.001; 8.29±3.42 mm vs 4.09±3.06 mm, t=5.504, P<0.001). The sex, age, BMI, affected side, meniscal injury side, time from injury to surgery, KT-1000 SSD, pivot shift test under anesthesia, follow-up duration between the two groups showed no significant difference ( P>0.05). Multivariable Logistic regressions indicated that PTS≥17° ( OR=15.62, P=0.002) and ATT≥6 mm ( OR=9.91, P=0.006) were independent risk factors for primary ACL reconstruction failure. However, sex, age, BMI, meniscal lesions, degree of pivot shift test, KT-1000 SSD were not the independent risk factors. Conclusion:PTS≥17° and ATT≥6 mm could increase the risk of primary ACL reconstruction failure.

Objective To investigate the risk factors of J sign in patients with recurrent patellar dislocation, and to estab?lish a new grading system of J sign. Methods From January 2017 to August 2018, a consecutive case series of 111 recurrent pa?tellar dislocation patients were included in the present study. Among these patients, a total of 68 patients had positive J sign (J sign (+) group), and the remaining 43 patients had negative J sign (J sign (-) group). Caton index, Dejour classification, tibial tuber?osity?trochlear groove (TT?TG) distance and rotational parameters of the lower extremity (including femoral anteversion angle, ex?ternal tibial torsion angle and knee rotation angle) were measured to compare the differences of these parameters between the inter?vention group and control group. Furthermore, the risk factors of J sign were analyzed in detail. Meanwhile, a new grading system of J sign was introduced based on the extent and form of lateral patellar shift. Results The prevalence of J sign in recurrent patel?lar dislocation was 61.3% (68/111). Univariate analysis showed that femoral anteversion angle (t=3.376, P=0.001), knee rotation angle (t=4.886, P=0.001), TT?TG distance (t=3.177, P=0.002) and prevalence of patellar alta (χ2=9.809, P=0.002) were much high?er in the J sign (+) group, and the differences were statistically significant when compared with the J sign (-) group. Multivariate Logistic regressions demonstrated that increased femoral anteversion angle ( OR=1.118, P=0.012), enlarged knee rotation angle ( OR=1.178, P=0.016) and patella alta ( OR=3.229, P=0.040) were independent risk factors of J sign in patients with recurrent pa?tellar dislocation. Conclusion Increased femoral anteversion angle, enlarged knee rotation angle, and patellar alta were strongly associated with J sign. These factors may be independent risk factors of J sign in patients with recurrent patellar dislocation.

Objective To investigate the effects of excessive pre?operative anterior tibial translation (ATT) on post?opera?tive knee stability after anterior cruciate ligament (ACL) reconstruction. Methods From January 2016 to December 2016, a total of 348 patients with noncontact ACL injuries who underwent primary anatomic single?bundle ACL reconstruction were retrospec?tively analyzed. The hamstring autograft was used as the grafted tendon. The ATT relative to the lateral femoral condyle was mea?sured on pre?operative magnetic resonance imaging (MRI) scans. Among them, twenty patients (ATT positive group) who demon?strated>10 mm ATT distance were matched in a 1∶2 fashion to 40 control participants (ATT negative group) with<3 mm ATT dis?tance. All patients were followed for at least 2 years. The post?operative clinical outcomes, including the ATT distance, the KT?1000 side?to?side difference, and the pivot?shift tests were compared between the two groups. Results The ATT distance of the ATT positive group was 13.5±1.3 mm, which was significantly larger than that of the ATT negative group (2.5±1.4 mm) (t=45.435, P=0.013) pre?operatively. At 2?year follow?up, the ATT distance of the ATT positive group was 9.7±1.8 mm, which was significant?ly larger than that of the ATT negative group (0.9±1.6 mm) (t=49.655, P=0.011). Moreover, the KT?1000 side?to?side difference of the ATT positive group was 4.4±1.5 mm, which was also significantly larger than that of the ATT negative group (0.8±1.1 mm) (t=38.945, P=0.014). There was significantly difference in the pivot?shift test between the two groups (ATT positive group: 1 grade 0, 18 grade I, 1 grade II vs. ATT negative group: 39 grade 0, 1 grade I) (χ2=40.521, P=0.012). Conclusion Excessive ATT could not be completely restored to normal after isolated anatomic single?bundle ACL reconstruction. Compared to the ATT negative group, the ATT positive group has inferior knee stability at 2?year follow?up.

Objective To discover the relationship between the post?operative positive residual patellar J sign and the laxity of reconstructed medial patellofemoral ligament (MPFL) after MPFL reconstruction combined with tibial tubercle osteotomy (TTO). Methods A total of 39 consecutive recurrent patellar dislocation (RPD) adult patients who were performed MPFL recon?struction and TTO with more than 2 follow?up time were analyzed retrospectively in the present study. The patellar tracking of all the patients was evaluated and was classified into positive patellar J sign group and negative J sign control group during knee ac?tive flexion and extension at final follow up. The computed tomography (CT) examination was performed in all patients at 0°exten?sion of the knee. The patellar laxity index measured by patellar glide test (PGT) and the radiographic parameters (tibial tuberosity?trochlear groove distance, bisect offset index, patella trochlear?groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle) calculated by CT scans slices as well as the pre?/post?operative knee functional scores including International Knee Documentation Committee (IKDC) score, Kujala score, and Lysholm score were compared be?tween the positive group and negative group at final follow up. Results The average follow?up duration was 26.3±6.7 months (range 24-31) and all the patients did not suffer from the RPD during the follow?up. Ten (26%, 10/39) patients performed positive J sign, and the remaining 29 (74%, 29/39) performed negatively. The two groups were compatible with no significant difference in age, gender, injury side, follow?up duration and preoperative knee function scores (P＞0.05). At the final follow up, the patellar laxity index in the positive J sign group was 34.9%±6.9%, while that in the negative group was 24.6%±8.6%. There was signifi?cantly difference in the patellar laxity index between two groups (t=-3.413, P=0.002). The bisect offset index in the positive group was 102.9%±12.4%, while that in the negative group was 76.0%±18.4%. There was significantly difference in the bisect offset in?dex between two groups (t=-4.268, P=0.000). The patella trochlear?groove distance in the positive group was 2.2±3.7 mm, while that in the negative group was-7.6±5.8 mm. There was significantly difference in the patella trochlear?groove distance between two groups (t=-4.233, P=0.000). The two groups were compatible with no significant difference in tibial tuberosity?trochlear groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle (P＞0.05). The IKDC, Kujala, and Lysholm in the positive group were 86.4±6.5, 85.3±1.1, 91.5±7.9 respectively with significantly differences compared with preoperative scores 53.3±2.4, 73.2±9.7, 76.7±6.6 (t=-10.163, P=0.000; t=-1.274, P=0.023; t=-8.533, P=0.018). The IKDC, Kujala, and Lysholm in the negative group were 87.3±8.6, 84.3±4.7, 93.1±4.3 respectively with significantly differences compared with preoperative scores 49.1±4.6, 71.4±6.5, 79.5±7.0 (t=-14.381, P=0.000; t=-0.068, P=0.037; t=-6.902, P=0.013). There were no significant difference in the postoperative knee function scores between the two groups (P＞0.05). Conclusion RPD patients can recover the patellar instability from the surgical technique of MPFL reconstruction and TTO and none of them suffer from the RPD during the follow?up. However, the morbidity of post?operative positive residual patellar J sign was 26%. The positive J sign might increase the laxity of patella.