BACKGROUND: The correlation between the morphological structure of the patellofemoral joint (PFJ) and the severity of knee joint osteoarthritis (KOA) remains uncertain. This study aims to investigate the correlation between the severity of knee joint osteoarthritis and the alignment of patellofemoral and patellar height on radiographs. METHODS: This multi-center, retrospective study analyzed the magnetic resonance imaging (MRI) scans and anteroposterior radiographs of 534 adult outpatients with KOA. To evaluate the radiographic severity of KOA, anteroposterior radiographs of the knee and the Kellgren-Lawrence (K-L) grade were used. Knee MRI scans were used to measure the patellar length ratio (PLR), sulcus angle (SA), lateral patellar tilt angle (LPTA), and the distance between tibial tuberosity and trochlear groove (TT-TG). We examined the association between the configuration of the PFJ, arrangement, and harshness of the KOA. Information on participants' demographics, such as age, sex, side, height, and weight, was collected. A chi-squared test was used for the correlation of radiographic severity of KOA with sex and the affected side. Spearman correlation was used for patellofemoral alignment or morphology and the radiographic severity of lateral KOA. Multiple linear regression models were used for the association between LPTA, SA, TT-TG, and severity of KOA after accounting for demographic variables. RESULTS: The study comprised of 534 patients; of these, 339 (63%) were female. A total of 586 knees were evaluated in this study. Age showed a strong positive correlation with KOA severity ( r  = 0.516, P <0.01), whereas LPTA showed a strong negative correlation ( r  = -0.662, P <0.01). Additionally, SA ( r  = 0.616, P <0.05), and TT-TG showed a strong positive correlation ( r  = 0.770, P <0.01) with tibiofemoral osteoarthritis (TFOA) severity. Multiple linear regression analysis indicated that knee osteoarthritis severity (β = -2.946, P <0.001) and side (β = -0.839, P  = 0.001) was associated with LPTA; knee osteoarthritis severity (β = 5.032, P <0.001) and age (β = -0.095, P <0.001) was associated with SA; knee osteoarthritis severity (β = 2.445, P <0.001), sex (β = -0.326, P  = 0.041), body mass index (β = -0.061, P  = 0.017) and age (β = -0.025, P <0.001) was associated with TT-TG. CONCLUSION Radiographic severity of KOA was positively associated with age, SA, and TT-TG but negatively associated with LPTA.
Humans ; Female ; Male ; Osteoarthritis, Knee/pathology* ; Middle Aged ; Retrospective Studies ; Aged ; Patellofemoral Joint/pathology* ; Magnetic Resonance Imaging ; Adult ; Patella/pathology* ; Radiography

OBJECTIVE: To investigate the effectiveness of modified single patellar tunnel medial patella femoral ligament (MPFL) reconstruction in the treatment of recurrent patellar dislocation. METHODS: Between 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.
Humans ; Patellar Dislocation/surgery* ; Male ; Female ; Plastic Surgery Procedures/methods* ; Adult ; Patellar Ligament/surgery* ; Recurrence ; Treatment Outcome ; Young Adult ; Adolescent ; Patella/surgery* ; Suture Anchors ; Hamstring Tendons/transplantation* ; Knee Joint/surgery* ; Transplantation, Autologous

OBJECTIVE: To explore the feasibility and effectiveness of suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique for avulsion fractures of the inferior pole of the patella. METHODS: A clinical data of 38 patients with avulsion fractures of the inferior pole of the patella, who met the selective criteria and were admitted between September 2021 and April 2023, was retrospectively analyzed. The fractures were treated with suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique in 18 cases (group A) and steel wire tension-band fixation in 20 cases (group B). There was no significant difference in terms of age, gender, cause of fracture, side of fracture, and disease duration between the two groups ( P>0.05). The length of incision, operation time, occurrence of complications, the range of motion of knee joint, and Böstman score of knee joint at last follow-up were recorded. The fracture healing was evaluated through X-ray films and the time of fracture healing was recorded. RESULTS: All incisions healed by first intention. The length of incision was significantly shorter in group A than in group B ( P<0.05). There was no significant difference in the operation time between the two groups ( P>0.05). All patients were followed up 12-24 months (mean, 16.1 months). X-ray films showed that all fractures healed and there was no significant difference in the healing time between the two groups ( P>0.05). At last follow-up, the range of motion and Böstman score of the knee joint in group A were significantly better than those in group B ( P<0.05). During follow-up, 1 patient (5.6%) in group A had one anchor mild prolapse and 3 patients (15.0%) occured internal fixation irritation in group B. But there was no significant difference in the incidence of complications between the two groups ( P>0.05). CONCLUSION For the avulsion fractures of the inferior pole of the patella, the suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique has advantages of reliable fixation, small incision, avoidance of secondary operation to remove internal fixator, and fewer complications, with definite effectiveness.
Humans ; Male ; Female ; Patella/surgery* ; Suture Anchors ; Fracture Fixation, Internal/instrumentation* ; Adult ; Retrospective Studies ; Middle Aged ; Fractures, Avulsion/surgery* ; Treatment Outcome ; Young Adult ; Range of Motion, Articular ; Fracture Healing ; Adolescent ; Suture Techniques ; Knee Joint/physiopathology*

OBJECTIVE: To investigate the effectiveness of three-needle and two-cable structure in the treatment of inferior patellar pole avulsion fractures. METHODS: A clinical data of 62 patients with inferior patellar pole avulsion fractures who were admitted between January 2023 and December 2023 and met the selection criteria was retrospectively analyzed. Among them, the fractures were fixed with three-needle and two-cable structure in 32 patients (observation group) and traditional steel wire tension band in 30 cases (control group). There was no significant difference in the baseline data of age, gender, side of the affected limb, cause of injury, and disease duration between the two groups ( P>0.05). The operation time, fracture healing and healing time, patellar height (Insall-Salvati index), occurrence of complications, knee range of motion, and Böstman score at last follow-up were compared between the two groups. RESULTS: The operation time of the observation group was significantly shorter than that of the control group ( P<0.05). Patients in both groups were followed up 6-12 months (mean, 10.4 months). X-ray films re-examination showed that all fractures healed, and the fracture healing time was significantly shorter in observation group than in control group ( P<0.05); no significant difference was found in Insall-Salvati index between the two groups ( P>0.05). During follow-up, the complications occurred in 2 cases (6.25%) of observation group and in 9 cases (30.00%) of control group, and the difference in the incidences between the two groups was significant ( P<0.05). At last follow-up, the range of motion and Böstman score of the knee joint in observation group were significantly superior to control group ( P<0.05). CONCLUSION Compared with the traditional steel wire tension band fixation, the three-needle and two-cable structure fixation of the inferior patellar pole avulsion fractures is firm, which allows the knee joint to move early after operation and is conducive to the recovery of knee joint function.
Humans ; Male ; Patella/surgery* ; Female ; Fracture Fixation, Internal/instrumentation* ; Retrospective Studies ; Adult ; Bone Wires ; Fractures, Avulsion/surgery* ; Middle Aged ; Young Adult ; Range of Motion, Articular ; Treatment Outcome ; Fracture Healing ; Needles ; Adolescent ; Operative Time

OBJECTIVE: To evaluate the early effectiveness of transosseous suture fixation in treating recurrent acute patellar dislocation with patellar osteochondral fractures (OCFs). METHODS: A retrospective analysis was conducted on 19 patients with recurrent acute patellar dislocation and patellar OCFs, who underwent transosseous suture fixation between January 2018 and December 2022 and were followed up 2 years. The cohort included 8 males and 11 females, aged 13-21 years (mean, 16.2 years). Patients experienced 2-5 times of patellar dislocation (mean, 3.2 times). The interval from the last dislocation to operation ranged from 3 to 15 days (mean, 9.6 days). Preoperative imaging revealed the intra-articular osteochondral fragments and medial patellofemoral ligament (MPFL) injury. Clinical outcomes were evaluated using the visual analogue scale (VAS) score for pain, the International Knee Documentation Committee (IKDC) score, the Hospital for Special Surgery (HSS) knee score, the Lysholm score, and the Tegner score. Postoperative complications were recorded. During follow-up, the knee X-ray films, CT, and MRI were taken to evaluate fragment healing, displacement, and the morphology and tension of the MPFL reconstruction graft. RESULTS: All incisions healed primarily, and no complication occurred such as infection, joint stiffness, patellofemoral arthritis, or redislocation. Patients were followed up 24-60 months (mean, 43.5 months). At 12 months postoperatively and the last follow-up, significant improvements ( P<0.05) were observed in VAS, Lysholm, IKDC, HSS, and Tegner scores compared to preoperative values. Further improvements were observed at last follow-up compared with the 12 months postoperatively, and the differences were significant ( P<0.05). Imaging studies demonstrated satisfactory osteochondral fragment positioning with stable fixation. At last follow-up, all fragments had healed, and MPFL reconstruction grafts exhibited optimal morphology and tension. No joint adhesion or fragment displacement occurred. CONCLUSION For recurrent acute patellar dislocation with patellar OCFs, transosseous suture fixation proves to be both safe and effective, achieving satisfactory early effectiveness.
Humans ; Male ; Female ; Patellar Dislocation/surgery* ; Adolescent ; Young Adult ; Retrospective Studies ; Patella/surgery* ; Suture Techniques ; Treatment Outcome ; Recurrence ; Fracture Fixation, Internal/methods* ; Fractures, Bone/surgery* ; Follow-Up Studies

OBJECTIVE: To evaluate the effectiveness of suture anchors combined with headless compression screw fixation in treating inferior pole patellar fractures. METHODS: A retrospective analysis was conducted on 36 patients with inferior pole patellar fractures, who were admitted between January 2018 and October 2024 and met the selective criteria. There were 15 males and 21 females with a mean age of 52.3 years (range, 23-81 years). The fracture were reduced and fixed using suture anchors combined with headless compression screws. The operation time, intraoperative blood loss, and the length of hospital stay were recorded. Functional recovery was assessed using knee range of motion (ROM), Hospital for Special Surgery (HSS) knee score, and Böstman patellar fracture efficacy score. RESULTS: The operation time ranged from 10 to 100 minutes, with an average of 57.6 minutes. The intraoperative blood loss was 10 to 120 mL, with an average of 73.3 mL. The length of hospital stay was 5 to 10 days, with an average of 6.3 days. All incisions healed by first intention. All 36 patients were followed up 18-24 months (mean, 20.6 months). Postoperative X-ray films indicated that the fractures had healed; no screw breakage, anchor loosening, or implant foreign body rejection reactions occurred during follow-up. At last follow-up, the ROM of the affected knee joint was (136.0±2.3)°, and there was no significant difference when compared with the healthy side (136.6±2.3)° ( t=-1.944, P=0.060). The HSS score of the affected knee joint was 96-100 (mean, 99.1), and all cases were rated as excellent. The Böstman patellar fracture efficacy score was 27-30 (mean, 29.1), and 35 cases were rated as excellent and 1 as good. CONCLUSION The suture anchors combined with headless compression screws technique provides reliable fixation for inferior pole patellar fractures. This method combines surgical simplicity with excellent functional outcomes.
Humans ; Male ; Female ; Middle Aged ; Bone Screws ; Aged ; Retrospective Studies ; Patella/surgery* ; Fracture Fixation, Internal/instrumentation* ; Adult ; Aged, 80 and over ; Suture Anchors ; Fractures, Bone/surgery* ; Range of Motion, Articular ; Treatment Outcome ; Young Adult ; Operative Time ; Length of Stay

OBJECTIVE: To exploring the efficacy of modified patellar triple surgery (including arthroscopic lateral retinaculum release, modified medial patellofemoral ligament reconstruction, and modified Fulkerson osteotomy) in the treatment of early patellofemoral osteoarthritis. METHODS: A retrospective analysis was conducted on 57 patients with patellofemoral arthritis admitted from March 2018 to June 2022, including 22 males and 35 females;aged 22 to 45 years old, average (31.5±5.7) years old; disease course 2 to 8 years (3.7±2.2) years;19 on the left side and 38 on the right side. The tendon graft was taken from the long tendons of the ipsilateral tibia, and the lateral patellar support band release was performed arthroscopically, combined with modified medial patellofemoral ligament reconstruction and modified Fulkerson osteotomy. The changes of Q angle, patellar tilt angle, tibial tuberosity-femoral trochlear groove (TT-TG) and Lysholm knee joint scores before and 12 months after surgery were compared. RESULTS: All patient incisions healed in stageⅠ, and 57 patients were followed up for 12 to 36 with an average of (22.1±2.5) months. The Q angle, patellar inclination angle, and TT-TG values improved from (22.7±1.9)°, (29.2±2.0)°, and (23.3±1.4) mm before surgery to (14.6±2.2)°, (7.6±3.2)°, and (11.8±1.7) mm one year after surgery, with statistically significant differences (P<0.05). The Lysholm score increased from preoperative (65.1±8.7) to postoperative (86.8±7.2) at 1 year (P<0.05), with 41 cases being excellent, 15 cases being good, and 1 case being average. CONCLUSION The improvement of medial patellofemoral ligament reconstruction and lateral retinaculum release can correct the Q angle in early patellofemoral osteoarthritis, while the improvement of Fulkerson osteotomy can correct the TT-TG value, elevate the patella, relieve pressure on the patellofemoral joint, and alleviate anterior knee pain. The clinical efficacy is definite, providing ideas for the clinical treatment of patellofemoral osteoarthritis.
Humans ; Male ; Female ; Adult ; Middle Aged ; Retrospective Studies ; Osteoarthritis, Knee/surgery* ; Patellofemoral Joint/surgery* ; Patella/surgery* ; Young Adult ; Osteotomy ; Arthroscopy

PURPOSE: Lateral patellar compression syndrome (LPCS) is characterized by a persistent abnormally high stress exerted on the lateral articular surface of the patella due to lateral patellar tilt without dislocation and lateral retinaculum contracture, leading to anterior knee pain. The purpose of this study is to evaluate the efficacy and prognosis of lateral retinaculum release (LRR) combined with chondroplasty in the treatment of LPCS. METHODS: This retrospective study evaluated 40 patients who underwent LRR combined with chondroplasty for LPCS between 2020 and 2021. The assessment included improvement in postoperative tenderness and knee joint function. Patients were evaluated using the Lysholm, Tegner, and International Knee Documentation Committee 2000 scoring systems, as well as the visual analog scale, both preoperatively and postoperatively, with the paired comparisons analyzed using a t-test. Additionally, intraoperative observations were made regarding knee joint lesions, including cartilage damage and osteophyte formation, with analysis by the Chi-square test. RESULTS: The visual analog scale score for tenderness showed a significant decrease after surgery (p < 0.001). Evaluation of knee joint function also indicated significant improvements, as demonstrated by increased Lysholm, Tegner, and International Knee Documentation Committee 2000 scores postoperatively (p < 0.001, p = 0.011, p < 0.001, respectively). Furthermore, all LPCS patients included in the study presented with cartilage injuries and osteophyte formation. Significant differences were noted in the incidence of cartilage damage and osteophyte formation at different locations within the knee among patients with LPCS. CONCLUSION LRR combined with chondroplasty is an effective surgical approach for treating patients with LPCS, with satisfactory recovery observed at the 1-year follow-up. Additionally, the incidence of cartilage damage and osteophyte formation in LPCS patients varies significantly depending on the specific location within the knee joint.
Humans ; Male ; Female ; Retrospective Studies ; Adult ; Middle Aged ; Patella/surgery* ; Knee Joint/physiopathology* ; Recovery of Function ; Young Adult ; Treatment Outcome ; Cartilage, Articular/surgery* ; Adolescent

OBJECTIVE: To investigate the midterm clinical efficacy of medial patellofemoral complex (MPFC) reconstruction for recurrent patellar dislocation with high-grade trochlear dysplasia. METHODS: A retrospective analysis was carried out among adult patients who underwent arthroscopically assisted MPFC reconstruction between January 2014 and December 2020. Dejour classification was evaluated to grade trochlear dysplasia; tibial tubercle-trochlear groove (TT-TG) distance and Insall-Salvati index were measured. Preoperative and postoperative patient-reported outcome measures (PROMs) were compared, including International Knee Documentation Committee (IKDC) score, Kujala score, Lysholm score and Tegner score. Information regarding returning-to-sport rate, re-instability events and complications was collected. Patellar tilt (PT), lateral patellar displacement (LPD) and bisect offset (BSO) ratio were measured based on axial computed tomography before and after surgery to assess the patellofemoral congruence. RESULTS: A total of 46 MPFC reconstructions in 43 patients were enrolled, including 16 male and 27 female. Mean age at surgery was (22.2±7.6) years (range: 14-44 years). Mean follow-up was (49.9±22.6) months (range: 18-102 months). The percentages of Dejour B, C and D dysplasia were 37.0% (17/46), 43.5% (20/46), and 19.6% (9/46), respectively. Mean Insall-Salvati index was 1.2±0.2 (range: 0.85-1.44), and mean TT-TG distance was (19.6±3.5) mm (range: 10.6-28.7 mm). At latest follow-up, there were significant improvements in all PROMs (P < 0.001): IKDC score, from 56.3±15.1 to 86.2±8.1; Kujala score, from 58.9±15.6 to 92.6±5.4; Lysholm score, from 63.7±15.0 to 94.0±5.7; Tegner score, from 3.1±1.4 to 4.7±1.4, and there were no significant differences in the improvements of the scores between the patients with Dejour B, C and D dysplasia. Overall, ninety percent of the patients returned to their preoperative sports level. One patient reported a postoperative subluxation, while no cases of infection, limited range of motion or patella fracture were observed. PT, LPD and BSO ratio were all significant altered (P < 0.001) after MPFC reconstruction. CONCLUSION Arthroscopically assisted MPFC reconstruction yielded satisfactory midterm clinical results for recurrent patellar dislocation with high-grade trochlear dysplasia. No significant differences of improvements in knee function were observed among the three types of high-grade trochlear dysplasia.
Humans ; Patellar Dislocation/surgery* ; Male ; Female ; Adult ; Arthroscopy/methods* ; Retrospective Studies ; Adolescent ; Young Adult ; Patellofemoral Joint/surgery* ; Recurrence ; Plastic Surgery Procedures/methods* ; Patella/surgery* ; Treatment Outcome

OBJECTIVE: To compare the mid- and long-term effectiveness of patellar resurfacing versus non-resurfacing in primary total knee arthroplasty (TKA). METHODS: Twenty-six patients who underwent bilateral TKA between March 2013 and September 2015 were selected as the study subjects. One side was randomly chosen for patellar resurfacing (resurfacing group), and the other side was not (control group). There were 4 males and 22 females, the age ranged from 51 to 65 years, with an average of 59 years. According to Kellgren-Lawrence classification, there were 21 cases of grade Ⅳ and 5 cases of grade Ⅲ in both knees. There was no significant difference in the surgical side, and preoperative clinical and functional scores of the Knee Society Score (KSS), visual analogue scale (VAS) score, and the composition ratio of anterior knee pain localization points between the two groups ( P>0.05). The operation time, intraoperative blood loss, postoperative abnormal signs such as patellar clunk, feeling of constraint, patellar tendon weakness, crepitus, or snow-on-glass sensation, and the occurrence of complications were recorded and compared. Patient subjective evaluations included Forgotten Joint Score (FJS) and the degree of difficulty in high-level knee activities (including flexion with load bearing, going upstairs, going downstairs, squatting and standing up, kneeling, knee extension, and crossing legs for 7 items); KSS clinical/functional scores and VAS scores were used to evaluate the recovery of knee joint function, and the location of anterior knee pain was determined by a localization diagram. RESULTS: The operation time of the resurfacing group was significantly longer than that of the control group ( P<0.05), and there was no significant difference in intraoperative blood loss between the two groups ( P>0.05). All patients' incisions healed by first intention; the hospital stay ranged from 8 to 23 days, with an average of 12.6 days. All patients were followed up 9-11 years, with an average of 9.7 years. Except for 1 case who died of multiple organ failure due to internal diseases at 9 years after operation and 5 cases with incomplete radiological data, the rest 20 patients were assessed radiologically and found that 1 side of the knee joint in the control group had patellar dislocation; the remaining patients had no prosthetic failure (fracture, loosening, displacement, etc.), patellar fracture, patellar necrosis, patellar instability, patellar tendon rupture, prosthetic revision, etc. No patients had reoperations due to patellar-related complications or anterior knee pain in both knee joints. At 2 years postoperatively and at last follow-up, there was no significant difference in the incidence of abnormal signs such as patellar clunk, feeling of constraint, patellar tendon weakness, crepitus, or snow-on-glass sensation, the incidence of high-level knee activity difficulty, and the composition ratio of anterior knee pain localization between the two groups ( P>0.05). The KSS clinical scores, functional scores, and VAS scores of both groups significantly improved compared to preoperative ones ( P<0.05); there was no significant difference in the comparison between the two groups at the two time points postoperatively ( P>0.05). At 2 years postoperatively and at last follow-up, there was no significant difference in FJS scores between the two groups ( P>0.05). CONCLUSION Patellar resurfacing or not has similar mid- and long-term effectiveness in primary TKA.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Male ; Middle Aged ; Female ; Patella/surgery* ; Aged ; Treatment Outcome ; Range of Motion, Articular ; Knee Joint/surgery* ; Knee Prosthesis ; Pain Measurement ; Osteoarthritis, Knee/surgery* ; Pain, Postoperative/etiology* ; Follow-Up Studies ; Postoperative Complications ; Recovery of Function