ObjectiveTo compare the strength difference between the interfacial screw and the interfacial screw combined with bone tunnel crossing technology to fix the tibial end of ligament during anterior cruciate ligament (ACL) reconstruction through the biomechanical test.MethodsTwenty fresh frozen pig tibia were randomly divided into two groups (n=10) to prepare ACL reconstruction models. The graft tendons in the experimental group were fixed with interfacial screw combined with bone tunnel crossing technology, and the graft tendons in the control group were fixed with interfacial screw. The two groups of specimens were fixed in the high-frequency dynamic mechanics test system M-3000, and the length change (displacement), ultimate load, and stiffness of graft tendons were measured through the reciprocating test and load-failure test.ResultsThe results of reciprocating test showed that the displacement of the experimental group was (3.06±0.58) mm, and that of the control group was (2.82±0.46) mm, and there was no significant difference between the two groups (t=0.641, P=0.529). The load-failure test results showed that the stiffness of the experimental group and the control group were (95.39±13.63) and (91.38±14.28) N/mm, respectively, with no significant difference (t=1.021, P=0.321). The ultimate load of the experimental group was (743.15±173.96) N, which was significantly higher than that of the control group (574.70±74.43) N (t=2.648, P=0.016).ConclusionIn ACL reconstruction, the fixation strength of tibial end with interface screw combined with bone tunnel crossing technology is obviously better than that of interface screw alone.
ObjectiveTo investigate the effects of different concentrations of osteoprotegerin (OPG) combined with deproteinized bone (DPB) on the bone tunnel after the anterior cruciate ligament (ACL) reconstruction. MethodsThe femoral epiphyseal side was harvested from newborn calf, and allogenic DPB were prepared by hydrogen peroxide-chloroform/methanol method. Then, DPB were immersed in 3 concentrations levels of OPG (30, 60, 100 μg/mL) and 3 concentration ratios (30%, 60%, 100%) of the gel complex were prepared. Sixty healthy New Zealand white rabbits, male or female, weighing (2.7±0.4) kg, were divided randomly into 4 groups (n=15):control group (group A), 30% (group B), 60% (group C), and 100% (group D) OPG/DPB gel complex. The ACL reconstruction models were established by autologous Achilles tendon. Different ratios of OPG/DPB gel complex were implanted in the femoral and tibial bone tunnel of groups B, C, and D, but group A was not treated. The pathology observation (including the percentage of the femoral bone tunnel enlargement) and histological observation were performed and the biomechanical properties were measured at 4, 8, and 12 weeks after operation. ResultsOne rabbit died of infection in groups A and D, 2 rabbits in groups B and C respectively, and were added. General pathology observation showed that the internal orifices of the femoral and tibia tunnels were covered by a little of scar tissue at 4 weeks in all groups. At 8 weeks, white chondroid tissues were observed around the internal orifices of the femoral and tibia tunnels, especially in groups C and D. At 12 weeks, the internal orifices of the femoral and tibia tunnels enlarged in groups A, B, and C, but it was completely closed in group D. At each time point, the rates of the femoral bone tunnel enlargement in groups B, C, and D were significantly lower than that in group A, and group D was significantly lower than groups B and C (P<0.05); group C was significantly lower than group B at 8 weeks, but no significant difference was found at 4 and 12 weeks (P<0.05). Hisological observation showed that fresh fibrous connective tissue was observed in 4 groups at 4 weeks; there was various arrangements of Sharpey fiber in all groups at 8 weeks and the atypical 4-layer structure of bone was seen in group D; at 12 weeks, Sharpey fiber arranged regularly in all groups, with typical 4-layer structure of bone in groups B, C, and D, and an irregular "tidal line" formed, especially in group D. Biomechanics measurement showed that the maximum tensile load in group D was significantly higher than that in groups A and B at 4 weeks (P<0.05), but no significant difference was shown among groups A, B, and C, and between groups C and D (P>0.05); at 8 weeks, it was significantly higher in groups C and group D than group A, and in group D than group B (P<0.05), but there was no significant difference between groups A, C and group B (P>0.05); at 12 weeks, it was significantly higher in groups C and D than groups A and B, and in group D than group C (P<0.05), but difference was not significant between groups A and B (P>0.05). ConclusionDifferent concentrations ratios of OPG/DPB gel complexes have different effects on the bone tunnel after ACL reconstruction. 100% OPG/DPB gel complex has significant effects to prevent the enlargement of bone tunnel and to enhance tendon bone healing.
Objective To compare the effectiveness between lower tibial tunnel placement combined with internal tension relieving suture and simple lower tibial tunnel placement for posterior cruciate ligament (PCL) reconstruction. MethodsThe clinical data of 83 patients with simple PCL injury who met the selection criteria between January 2014 and February 2022 were retrospectively analyzed. Among them, 44 patients underwent PCL reconstruction through lower tibial tunnel placement combined with internal tension relieving suture (tension relieving suture group), and 39 patients underwent PCL reconstruction through simple lower tibial tunnel placement (control group). Baseline characteristics, including gender, age, body mass index, side of injury, cause of injury, preoperative side-to-side difference (SSD) in posterior tibial translation, visual analogue scale (VAS) score, knee range of motion (ROM), Tegner score, Lysholm score, and International Knee Documentation Committee (IKDC) scores (including symptom, daily activities, and knee function scores) were compared between the two groups, showing no significant difference (P>0.05). The operation time and intraoperative blood loss were recorded and compared between the two groups. The effectiveness was evaluated by Lysholm score, IKDC scores, Tegner score, VAS score, knee ROM, SSD in posterior tibial translation before operation and at last follow-up, the patient satisfaction at last follow-up, and the postoperative graft recovery was evaluated by MRI. ResultsThere was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). All patients were followed up 12-60 months, and there was no significant difference between the two groups (P>0.05). Postoperative MRI showed that the graft was in good condition, and the reconstructed PCL graft had good signal, continuity, and tension. During the follow-up, there was no complication such as re-rupture or donor site discomfort in both groups. At last follow-up, the Lysholm score, IKDC scores, Tegner score, VAS score, knee ROM, and SSD in posterior tibial translation significantly improved in both groups when compared with those before operation (P<0.05). The changes of Lysholm score, Tegner score, IKDC knee symptom score, and SSD in posterior tibial translation between pre- and post-operation were significantly superior in the tension relieving suture group compared to the control group (P<0.05). However, no significant difference was found between the two groups in the changes of VAS score, knee ROM, IKDC daily activities score or knee function score between pre- and post-operation, and the satisfaction score (P>0.05). ConclusionLower tibial tunnel placement combined with internal tension relieving suture PCL reconstruction represents a more effective surgical approach for improving postoperative laxity of PCL and knee function recovery comparing to simple lower tibial tunnel placement PCL reconstruction.
To observe the histology change of the insertion using different diamertrical bone tunnel in anterior cruciate l igament (ACL) reconstruction. Methods Ninety Japanese rabbits were selected, wihout female and male l imit, weighing 2.5-3.0 kg, and were randomly divided into 3 groups, 30 in each group. The ratio of transplantation l igament diameter and bone tunnel diameter was 1/1 (group A), the ratio was 1/1.5 (group B), and the ratio was 1/2 (group C). Bone tunnel observation and histology observation were carried out in the 4th, 8th and 16th weeks postoperat ively. Results Wound healed well in 3 groups. The mean time of walking functional recovery was 1.5, 2.0 and 3.5 days in groups A, B and C respectively. After 4 weeks of operation, more soft tissues at tunnel entry were observed in group A and group B than in group C; after 8 weeks of operation, there was no crevice at bone-tunnel entry of the groups A and B, there was no improvement in group C; after 16 weeks of operation, groups A and B showed the normal insertion, group C had no normal insertion. Histology observation: in groups A, B and C, bone-tunnel was filled with loose connective tissue after 4 weeks of operation; group A and group B emerged the discontinuation ACL insertion tidal l ine after 8 weeks of operation, group C had no insertion; groups A and B emerged the similarity normal ACL insertion tidal l ine structure after 16 weeks of operation, but group C had no this structure. The results of ultimate tensile strength in groups A, B and C were (75.44 ± 7.06), (91.37 ± 6.14) and (126.91 ± 4.61) N respectively at 4 weeks; the results were (74.31 ± 4.81), (88.30 ± 7.46) and (124.34±8.44) N respectively at 8 weeks; and the results were (62.20 ± 5.32), (71.53 ± 5.99) and (83.62 ± 5.69) N respectively at 16 weeks. There was no significant difference between group A and group B (P gt; 0.05), and there were significant differences between groups A, B and group C (P lt; 0.05). Conclusion In the ACL reconstruction, the ratioof transplantation l igament diameter and bone tunnel diameter being 1/1.5 will not affect the insertion outcome, but if theratio less than the l imit it will affect the insertion outcome.
ObjectiveTo study the effect of the femoral tunnel position on the knee function recovery after medial patellofemoral ligament (MPFL) reconstruction. MethodsA retrospective analysis was made on the clinical date of 43 cases (43 knees) of recurrent patellar dislocation undergoing MPFL reconstruction and patellofemoral lateral retinaculum lysis between August 2013 and March 2014. There were 12 males and 31 females, aged 19.4 years on average (range, 9-35 years). All patients had trauma history and recurrent dislocations. The results of apprehesion test and J syndrom were positive. The patellar tilt test showed patellofemoral lateral retinaculum was tension. The effectiveness was evaluated using Lysholm knee functional score after operation. The distance from the center of the femoral tunnel to the femoral isometric point was measured on CT three dimensional reconstruction image. Whether the femoral tunnel position was isometric was evaluated. The correlation was analyzed between the distance from the center of the femoral tunnel to the femoral isometric point and Lysholm score. ResultsPrimary healing of incision was obtained in all patients. The patients were followed up 13-18 months (mean, 15 months). No patellar dislocation or subluxation occurred. The result of apprehensive test was negative. At last follow-up, the average Lysholm score was 93.8 (range, 83-100). The average distance from the center of the femoral tunnel to the femoral isometric point was 5.61 mm (range, 2-16 mm). The femoral tunnel position was isometric in 30 cases (69.8%) and non-isometric in 13 cases (30.2%). The distance from the center of the femoral tunnel to the femoral isometric point was negatively correlated with postoperative Lysholm score (r=-0.851, P=0.000). The postoperative Lysholm score was 95.7±2.3 in patients with isometric tunnel and was 89.4±3.5 in patients with non-isometric tunnel, showing significant difference (t=6.951, P=0.000). ConclusionFor patellofemoral joint instability, preparing the femoral isometric tunnel can establish a good foundation for the recovery of the knee function in MPFL reconstruction.
Objective To investigate the changes of knee joint kinematics after anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral positioner based on the apex of deep cartilage (ADC). Methods Between January 2021 and January 2022, a total of 40 patients with initial ACL rupture who met the selection criteria were randomly divided into the study group (using the personalized femoral positioner based on ADC design to assist ACL reconstruction) and the control group (not using the personalized femoral positioner to assist ACL reconstruction), with 20 patients in each group. Another 20 volunteers with normal knee were collected as a healthy group. There was no significant difference in gender, age, body mass index, and affected side between groups (P>0.05). Gait analysis was performed at 3, 6, and 12 months after operation using Opti _ Knee three-dimensional knee joint motion measurement and analysis system, and the 6 degrees of freedom (flexion and extension angle, varus and valgus angle, internal and external rotation angle, anteroposterior displacement, superior and inferior displacement, internal and external displacement) and motion cycle (maximum step length, minimum step length, and step frequency) of the knee joint were recorded. The patients’ data was compared to the data of healthy group. Results In the healthy group, the flexion and extension angle was (57.80±3.45)°, the varus and valgus angle was (10.54±1.05)°, the internal and external rotation angle was (13.02±1.66)°, and the anteroposterior displacement was (1.44±0.39) cm, the superior and inferior displacement was (0.86±0.20) cm, and the internal and external displacement was (1.38±0.39) cm. The maximum step length was (51.24±1.29) cm, the minimum step length was (45.69±2.28) cm, and the step frequency was (12.45±0.47) step/minute. Compared with the healthy group, the flexion and extension angles and internal and external rotation angles of the patients in the study group and the control group decreased at 3 months after operation, and the flexion and extension angles of the patients in the control group decreased at 6 months after operation, and the differences were significant (P<0.05); there was no significant difference in the other time points and other indicators when compared with healthy group (P>0.05). In the study group, the flexion and extension angles and internal and external rotation angles at 6 and 12 months after operation were significantly greater than those at 3 months after operation (P<0.05), while there was no significant difference in the other indicators at other time points (P>0.05). There was a significant difference in flexion and extension angle between the study group and the control group at 6 months after operation (P<0.05), but there was no significant difference of the indicators between the two groups at other time points (P>0.05).Conclusion Compared with conventional surgery, ACL reconstruction assisted by personalized femoral positioner based on ADC design can help patients achieve more satisfactory early postoperative kinematic results, and three-dimensional kinematic analysis can more objectively and dynamically evaluate the postoperative recovery of knee joint.
ObjectiveTo evaluate the effectiveness of femoral oval tunnel technique versus round tunnel technique in single-bundle anterior cruciate ligament (ACL) reconstruction.MethodsBetween March 2016 and February 2018, 125 patients who underwent anatomical single-bundle ACL reconstruction with hamstring tendon and met the inclusive criteria were included in the retrospective study. Of the included patients, 43 patients underwent ACL reconstruction using oval tunnel technique (group A) and 82 patients with round tunnel technique (group B). There was no significant difference between the two groups in terms of age, gender, body mass index, the interval between injury and operation, the injured side, the cause of injury, and preoperative Lysholm score, International Knee Documentation Committee (IKDC) score, Tegner score, and the outcome of KT-1000 measurement (P>0.05). At 3, 6, 12, and 24 months after operation, the knee function scores (Lysholm score, IKDC score, Tegner score) were recorded; and KT-1000 was used to evaluate the knee stability. The position and shape of the tunnels were evaluated by the three-dimensional CT (3D-CT) at 1 day after operation; and MRI was performed at 6, 12, and 24 months to calculate the signal/noise quotient (SNQ) of ACL grafts. Secondary arthroscopy was conducted to estimate the graft status, synovial coverage, and tension.ResultsAll patients were followed up 12-26 months (mean, 23 months). Two patients in group A and 5 patients in group B presented with redness and swelling of the surgical site, 1 patient in group B sustained a tibial tunnel fracture, and 1 patient in group A had postoperative stiffness. The Lysholm score, IKDC score, and Tegner score were significantly higher in group A than in group B at the different time points (P<0.05) except for the Tegner score at 3 months. The outcomes of KT-1000 measurement were significantly lower in group A than in group B (P<0.05). The entrances of the femoral tunnel and tibial tunnel in both groups were within the ACL anatomical footprint confirmed by 3D-CT. No re-rupture of ACL occurred confirmed by the MRI. There was no significant difference in SNQs of the middle and distal grafts between the two groups at 6 months (P>0.05), whereas the SNQ of the proximal grafts in group A was significantly lower than that in group B (P<0.05). The SNQs of the proximal, middle, and distal grafts in group A were significantly lower than those in group B at 12 and 24 months after operation (P<0.05). Twenty-one patients in group A and 38 patients in group B underwent secondary arthroscopy and the results showed no significant difference in graft status, synovial coverage, and tension between the two groups (P>0.05).ConclusionThe effectiveness and graft maturity of the femoral oval tunnel technique were superior to the round tunnel technique. The single-bundle ACL reconstruction with femoral oval tunnel technique can obtain a better knee function.
ObjectiveTo introduce the method of prior-localization femoral tunnel by using a special positioning tool under the C-arm radiographic machine before surgery, and to study the effect on the knee function recovery after medial patellofemoral ligament (MPFL) reconstruction.MethodsBetween January 2014 and January 2016, 32 patients with recurrent unilateral knee patellar dislocation were treated by arthroscopic patellofemoral lateral retinaculum release and MPFL reconstruction. The femoral tunnel position during MPFL reconstruction was prior-localizated under C-arm radiographic machine before operation. There were 8 males and 24 females, aged from 15 to 37 years, with an average of 23.8 years. The time from injury to admission ranged from 1 to 24 months, with an average of 9.7 months. Isometric point distance was measured on CT three-dimensional reconstruction image after operation to evaluate whether the position of femoral tunnel was isometric, and knee joint function was evaluated by Lysholm score. Spearman correlation analysis was performed between isometric point distance and Lysholm score.ResultsAll the 32 patients were followed up 12-18 months (mean, 14.2 months). No symptoms of patellar subluxation or dislocation was found during follow-up. Patellar extrapolation test and patellar extrapolation fear test were negative. The isometric point distance was 1.5-5.9 mm (mean, 3.44 mm) at 3 days after operation. All femoral tunnels were located in equidistant tunnels. At last follow-up, the Lysholm score of the patients was 92.8±2.1, which was significantly improved when compared with preoperative score (54.4±2.8) (t=61.911, P=0.000). Isometric point distance was negatively correlated with Lysholm score (r=–0.454, P=0.009).ConclusionC-arm radiographic machine can locate the femoral tunnel position of MPFL easily and accurately before operation. The short-term and medium-term effectiveness are satisfactory, and the ionizing radiation injury caused by multiple fluoroscopy during operation is avoided.
Objective To investigate the effectiveness of modified single patellar tunnel medial patella femoral ligament (MPFL) reconstruction in the treatment of recurrent patellar dislocation. MethodsBetween January 2023 and June 2023, a total of 61 patients with recurrent patellar dislocation who underwent MPFL reconstruction with autologous semitendinosus were enrolled and divided into 2 groups using random number table method. In the patellar anchor group, 31 patients were treated with MPFL reconstruction with double medial patellar anchors, and 30 patients in the patellar tunnel group were treated with MPFL reconstruction with single patellar tunnel. The femoral ends of both groups were fixed with absorbable compression screws. There was no significant difference in baseline data such as gender, age, side, tibial tubercle-trochlear groove (TT-TG), Q angle, Caton-Deschamps index, number of dislocation, and preoperative Kujala score, preoperative patellar inclination angle (P>0.05). Patellar tunnel, patellar anchor position, patellar reduction, and the patellar inclination angle were measured by CT scan after operation. Kujala score was used to evaluate the function of knee joint before operation, at 2 weeks and 1, 3, 6, 12 months after operation. Incision aesthetic satisfaction score was performed at 3 months after operation. The signal-to-noise quotient (SNQ) of the transplanted tendon was measured by knee MRI at 12 months after operation to compare the maturity of the graft between the two groups. Results There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). Knee CT reexamination showed that the patellar tunnel and the patellar anchor position were consistent with the intraoperative fluoroscopy. There was no significant difference in the difference of the patellar inclination angle between the two groups before and after operation (P>0.05). All patients were followed up 12-14 months (mean, 12.8 months). There was 1 case of patellar anchor suture rejection in patellar anchor group, and the wound healed after debridement and dressing change. During the follow-up, there was no complication such as recurrence of patellar dislocation, infection and postoperative stiffness. The Kujala scores of the two groups significantly improved at each time point after 1 month of operation when compared with those before operation (P<0.05), and the Kujala scores of the two groups returned to normal levels at 3 months after operation. The Kujala score in the patellar tunnel group was significantly higher than that in the patellar anchor group in the very early stage (2 weeks) (P<0.05), and there was no significant difference between the two groups at other time points (P>0.05). Patients in the patellar tunnel group were significantly better than those in the patellar anchor group in the score of incision aesthetic satisfaction at 3 months after operation and the SNQ at 12 months after operation (P<0.05). Conclusion Modified single patellar tunnel MPFL reconstruction was used to treat patients with recurrent patellar dislocation without pathological TT-TG. The slide-fixation structure formed by single patellar tunnel positioning provides a variable degree of freedom for the reconstructed MPFL, which shows good effectiveness in the very early stage of the rehabilitation process.