ObjectiveTo investigate the clinical significance of Q-angle measuring under different conditions in female recurrent patellar dislocation female patients. MethodsBetween August 2012 and March 2013, 10 female patients (11 knees) with recurrent patellar dislocation were collected as trial group; 20 female patients (20 knees) with simple meniscus injury were collected as control group at the same time. Q-angle was measured in extension, 30° flexion, 30° flexion with manual correction, and surgical correction in the trial group, and only in extension and 30° flexion in the control group. Then the difference value of Q-angle between extension and 30° flexion (Q-angle in extension subtracts Q-angle in 30 flexion) were calculated. Independent sample t-test was used to analyze Q-angle degrees in extension, 30° flexion, and the changed degrees of 2 groups. The Q-angle between manual correction and surgical correction of the trial group was analyzed by paired t-test. ResultsThe Q-angle in extension, Q-angle in 30° flexion, and difference value of Q-angle between extension and 30° flexion were (17.2±3.6), (14.3±3.0), and (2.9±1.9)° in the trial group and were (15.2±3.4), (14.4±3.5), and (0.8±1.7)° in the control group. No significant difference was found in Q-angle of extension or Q-angle of 30° flexion between 2 groups (P>0.05), but the difference value of Q-angle between extension and 30° flexion in the trial group was significantly larger than that in the control group (t=3.253, P=0.003). The Q-angle in 30° flexion with manual correction and surgical correction in the trial group was (19.8±3.4)° and (18.9±3.8)° respectively, showing no significant difference (t=2.193, P=0.053). ConclusionWhen a female patient's Q-angle in 30° flexion knee changes obviously compared with Q-angle in extension position, recurrent patellar dislocation should be considered. For female patients with recurrent patellar dislocation, the preoperative Q-angle in 30° flexion with manual correction should be measured, which can help increasing the accuracy of evaluation whether rearrangement should be performed.
Objective To review research progress on femoral attachment positioning during medial patellofemoral ligament (MPFL) reconstruction, so as to provide a reference for accurate positioning in clinic. Methods The literature at home and abroad on femoral attachment positioning during MPFL reconstruction was extensively reviewed and summarized. Results MPFL is the main ligament that restricts patellar outward migration, so MPFL reconstruction is the main treatment for patellar dislocation, but the accuracy of intraoperative femoral attachment positioning will significantly affect the effectiveness. At present, there are three main methods for femoral attachment positioning in MPFL reconstruction, including imaging positioning, bony landmark positioning, and new technology. Among them, the main imaging positioning method is the “Schöttle point” method, but it has high requirements for fluoroscopic positioning, and can only be accurately positioned under standard lateral fluoroscopy of the femur. The bony landmark positioning method mainly locates the femoral attachment by touching or dissecting the bony landmarks such as adductor tubercles and medial epicondyle of femur, but its disadvantages are that the positioning is not accurate enough, the intraoperative visual field exposure requirements are high, and a large incision is required. In order to avoid the problem that the simple bony landmark positioning method, in recent years, the combination of bony landmarks combined with arthroscopy, three-dimensional (3D) printing technology, and robot-assisted positioning methods have begun to be used in clinical practice. New technology localization methods have shown good results by preparing guides before operation, planning positioning paths in advance, or directly using robots to assist positioning during operation. Conclusion The accurate positioning of the femoral attachment in MPFL reconstruction is crucial, and the method of accurate and rapid intraoperative determination needs to be further improved and optimized. In the future, it is expected that the combination of computer image recognition correction technology and intraoperative position assistance will solve this problem.
ObjectiveTo investigate the short-term effectiveness of derotational distal femoral osteotomy (DDFO) combined with medial patellofemoral ligament (MPFL) reconstruction in treatment of recurrent patellar dislocation with excessive femoral anteversion angle (FAA≥30°). MethodsBetween June 2017 and August 2019, 17 patients with recurrent patellar dislocation with FAA≥30° were treated with DDFO and MPFL reconstruction. There were 5 males and 12 females, aged 14-22 years, with an average of 17.7 years. The patella dislocated for 2 to 8 times (mean, 3.6 times). The disease duration was 2-7 years (mean, 4.6 years). The patellar apprehension tests were positive. Preoperative pain visual analogue scale (VAS) score, Lysholm score, Tegner score, and Kujala score were 4.2±1.1, 47.8±8.1, 3.6±1.1, and 56.8±5.7, respectively. FAA, mechanical lateral distal femoral angle (mLDFA), lateral patella displacement (LPD), tibial tuberosity-trochlear groove distance (TT-TG) were (34.9±3.4)°, (85.8±3.0)°, (13.7±3.8) mm, and (23.1±2.1) mm, respectively. ResultsAll incisions healed by first intention, and there was no complications such as knee stiffness, infection, and re-dislocation of the patella. All patients were followed up 13-25 months, with an average of 17.7 months. The imaging review showed that 1 case of osteotomy did not union, and achieved satisfactory results after the secondary revision and strengthening fixation; the osteotomies of other patients healed completely after 3 to 4 months of operation. The patellar apprehension tests were negative. At last follow-up, the FAA, mLDFA, LPD, and TT-TG were (15.6±2.7)°, (83.0±2.1)°, (5.0±2.6) mm, and (20.5±2.5) mm, respectively; the VAS score, Lysholm score, Tegner score, and Kujala score were 2.4±1.4, 93.4±7.8, 6.8±1.5, and 89.0±8.0, respectively. There were significant differences in the above indicators between pre- and post-operation (P<0.05). ConclusionDDFO combined with MPFL reconstruction for the recurrent patellar dislocation with excessive FAA (≥30°) can achieve good short-term effectiveness, significantly reduce knee pain, and improve function.
ObjectiveTo summarize the progress of research related to the surgical treatment of recurrent patellar dislocation by peripatellar osteotomy in clinical practice, in order to provide reference for clinical treatment. MethodsThe recent literature on peripatellar osteotomy for recurrent patellar dislocation at home and abroad was reviewed, and the bony structural abnormalities, imaging diagnosis, and treatment status were summarized. ResultsAbnormalities in the bony anatomy of the lower limb and poor alignment lead to patellofemoral joint instability through the quadriceps pulling force line and play an important role in the pathogenesis of recurrent patellar dislocation. Identifying the source of the deformity and intervening with peripatellar osteotomy to restore the biomechanical structure of the patellofemoral joint can reduce the risk of soft tissue surgical failure, delay joint degeneration, and achieve the target of treatment. ConclusionIn the clinical diagnosis and treatment of recurrent patellar dislocation, the factors causing patellofemoral joint instability should be comprehensively evaluated to guide the selection of surgery and personalized treatment.
Objective To investigate the cl inical therapeutic results of allograft tendon for anatomical reconstruction of medial patellofemoral l igament (MPFL) in patellar dislocations. Methods From September 2005 to June 2008, 20 patientswith patellar dislocation underwent MPFL reconstructions. There were 4 males and 16 females, aged 13 to 31 years (19 years on average). Patellar dislocations occurred in 7 left and 13 right knees, including 6 cases of acute dislocation and 14 cases of recurrent dislocation. The disease course was 1 day to 2 years. The frequency of dislocation was 1-6 (4 on average). Affected knee joint showed pain, swell ing and patellar instabil ity; the range of action for patella obviously increased. The X-ray films showed patellar dislocation or medial margin avulsion fracture. The preoperative Q angle was (15 ± 3)°, the congruence angle was (10 ± 11)°. Reconstruction was performed via allograft tendon. Allograft tendon was anchored to the superomedial pole of the patella by two bone anchors, and the other end was fixed at the natural MPFL insertion site near the medial femoral condyle with an interference screw in a bone tunnel. All patients were evaluated postoperatively; Kujala patellofemoral scores, objective knee function, compl ications, and reoperations were assessed. Results Primary heal ing was achieved in 18 cases and secondary heal ing in 2 cases. No infection or necrosis and absorption of grafts was observed. All patients were followed up for an average of 25.6 months (range, 6-34 months) postoperatively. At last follow-up, other patients had no pain, swell ing and patellar instabil ity except 1 case; neither patella redislocation nor fracture occurred. The X-ray films showed good position of anchors and tunnel 6 months after operation, and the congruence angle was (3 ± 8)°, showed statistically significant difference when compared with preoperation (P lt; 0.05). The postoperative Q angle was (15 ± 2)°, the Kujala knee function score improvedsignificantly from 60.8 ± 7.2 to 83.4 ± 8.0 at last follow-up, showing statistically significant difference (P lt; 0.05). According to Insall et al. for function, the results were excellent in 12 cases, good in 6 cases, and fair in 2 cases, the excellent and good rate was 90%. Conclusion MPFL reconstruction improves cl inical symptoms. Anatomical MPFL reconstruction is effective for patellar dislocation, and it offer good recovery of the pre-morbid patella mechanics. There would be l ittle bone loss when tendon is fixed by anchors, and there would be less patellar fracture than bone tunnel technique. The bone anchors also provide firm fixation. Allograft can avoid the graft harvest site morbidity, but it increases the cost of the surgery.
ObjectiveTo investigate the effectiveness of arthroscopic medial patellofemoral ligament (MPFL) reconstruction combined with tibial tuberosity transfer for recurrent patellar dislocation.MethodsBetween February 2012 and December 2013, 24 patients (24 knees) with recurrent patellar dislocation were treated with arthroscopic MPFL reconstruction combined with tibial tuberosity transfer. There were 7 males and 17 females, with a mean age of 23.2 years (range, 18-37 years). One patient had recurrence dislocation after operation in the other hospital, and the others were the first operation. The disease duration ranged from 6 months to 20 years (mean, 5.6 years). The patellar apprehension tests were positive. The preoperative Lysholm score was 49.79±11.67 and the Kujala score was 49.63±6.28. X-ray films showed that 13 patients had dysplasia of the patella and femoral trochlea; 8 patients had high tibia (Caton-Deschamps index>1.2); the congruence angle was (23.96±5.54)°. CT examination showed that the tibial tuberosity-trochlear groove distance (TT-TG) value was (23.71±2.35) mm.ResultsAll incisions healed by first intention. Twenty-two patients were followed up 59-81 months, with an average of 66.8 months. No dislocation occurred during the follow-up period. The patellar apprehension tests were negative. At 1 week after operation, the results of X-ray films and CT showed that the congruence angle angle was (–1.96±4.65)°, and the TT-TG value was (13.75±1.89) mm, which were significantly lower than those before operation (P<0.05). At 6 months, 1 year, and last follow-up, Lysholm scores were 81.13±17.76, 91.35±3.60, and 92.23±2.71, respectively; and Kujala scores were 84.04±3.98, 91.48±3.64, and 91.45±3.29, respectively. The Lysholm and Kujala scores were significantly increased after operation when compared with the preoperative scores (P<0.05). At last follow-up, the effectiveness was excellent in 11 cases, good in 8 cases, and fair in 3 cases, with an excellent and good rate of 86%.ConclusionArthroscopic MPFL reconstruction combined with tibial tuberosity transfer for recurrent patellar dislocation can effectively improve the patellofemoral joint matching relationship and has a satisfactory short- and medium-term effectiveness.
From 1974 to 1993, 20 patients with dislocation of patella in 26 knees were treated by surgical technique, including 11 males and 9 females, aged from 10 to 67,averaged 31 year old. Thirteen cases (16 knees) were available for followup with an average period of 6.4 years. Using the criteria of Insall, the result were excellent in 5 knees, good in 5 knees, fair in 3 knees and poor in 3 knees with a success rate of 62%. Based on the biomechanism of patella movement and the findings in this study, the mechanism of dislocation of patella and its biomechanical reconstruction principle as well as the factors influencing the operative results were discussed.
ObjectiveTo evaluate the operability and effectiveness of a self-developed patellar bone canal locator (hereinafter referred to as “locator”) in the reconstruction of the medial patellofemoral ligament (MPFL). Methods A total of 38 patients with recurrent patellar dislocation who met the selection criteria admitted between January 2022 and December 2022 were randomly divided into study group (the patellar canal was established with a locator during MPFL reconstruction) and control group (no locator was used in MPFL reconstruction), with 19 cases in each group. There was no significant difference in baseline data between the two groups (P>0.05), such as gender, age, body mass index, disease duration, patella Wiberg classification, constituent ratio of cartilage injury, Caton index, tibia tubercle-trochlear groove, and preoperative Lysholm score, Kujal score, Tegner score, visual analogue scale (VAS) score, and so on. The Lysholm score, Kujal score, Tegner score, and VAS score were used to evaluate knee joint function before operation and at 3 days,1 month, 3 months, and 6 months after operation. The ideal prepatellar cortical thickness and canal length were measured before operation, and the actual prepatellar cortical thickness and canal length after operation were also measured, and D1 (the distance between the ideal entrance and the actual entrance), D2 (the ideal canal length minus the actual canal length), D3 (the ideal prepatellar cortical thickness minus the actual prepatellar cortical thickness) were calculated.ResultsPatients in both groups were followed up 6-8 months (mean, 6.7 months). The incision length and intraoperative blood loss in the study group were smaller than those in the control group, but the operation time was longer than that in the control group, the differences were significant (P<0.05). There was no complication such as incision infection, effusion, and delayed healing in both groups, and no further dislocation occurred during follow-up. One patient in the study group had persistent pain in the anserine area after operation, and the symptoms were relieved after physiotherapy. The VAS score of the two groups increased significantly at 3 days after operation, and gradually decreased with the extension of time; the change trends of Lysholm score, Kujal score, and Tegner score were opposite to VAS score. Except that the Lysholm score and Kujal score of the study group were higher than those of the control group at 3 days after operation, and the VAS score of the study group was lower than that of the control group at 3 days and 1 month after operation, the differences were significant (P<0.05), there was no significant difference in the scores between the two groups at other time points (P>0.05). Patellar bone canal evaluation showed that there was no significant difference in preoperative simulated ideal canal length, prepatellar cortical thickness, and postoperative actual canal length between the two groups (P>0.05). The postoperative actual prepatellar cortical thickness of the study group was significantly smaller than that of the control group (P<0.05). D1 and D3 in the study group were significantly higher than those in control group (P<0.05), but there was no significant difference in D2 between the two groups (P>0.05). ConclusionThe locator can improve the accuracy of MPFL reconstruction surgery, reduce the possibility of intraoperative damage to the articular surface of patella and postoperative patellar fractures.
ObjectiveTo investigate the effectiveness of the arthroscopic lateral retinacular release combined with medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation.MethodsBetween January 2016 and March 2017, 28 cases (32 knees) with patellar dislocation were treated by arthroscopic lateral retinacular release and MPFL reconstruction. There were 6 males (6 knees) and 22 females (26 knees) with an average age of 21 years (range, 17-29 years). The disease duration ranged from 2 days to 2 years (mean, 8 months). Apprehension test of all patients were positive. The preoperative Lysholm score was 68.34±12.26. Anteroposterior X-ray film showed the patellar subluxation or dislocation. The Q angle was (17.67±4.21)° and the distance of tibia tuberosity-trochlear groove was less than 20 mm. The femoral attachment of retinacular were fixed by the interference screws (16 knee) or the anchors (16 knee), respectively.ResultsAll incisions healed by first intention. All patients were followed up 6 months. The function of knee joint was significantly improved at 6 months after operation. The Lysholm score was 92.88±6.42 and the Q angle was (12.15±3.68)° at 6 months. There were significant differences in the Lysholm score and the Q angle between pre- and post-operation (t=–3.408, P=0.006; t=–2.317, P=0.004). Apprehension test of all patients were negative. No knee pain, knee weakness, and patellar dislocation occurred during follow-up. There was no significant difference in the Lysholm score and the Q Angle between the anchor group and interference screw group (t=–3.254, P=0.820; t=–3.576, P=0.940). ConclusionLateral retinacular release combined with MPFL reconstruction under arthroscopy can effectively improve the function of the knee joint for patients with Q angle less than 20° and TT-TG less than 20 mm, and the early effectiveness is good. There is no significant difference in knee function between the anchor and interference screw internal fixation.
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.