BACKGROUND: Patellofemoral joint (PFJ) degeneration has traditionally been regarded as a contraindication to unicompartmental knee arthroplasty (UKA). More recently, some researchers have proposed that PFJ degeneration can be ignored in medial UKA, and others have proposed that this change should be reviewed in PFJ degenerative facets and severity. This study aimed to systematically evaluate the effect of PFJ degeneration on patient-reported outcome measures (PROMs) and revision rates after medial UKA. METHODS: Electronic databases (PubMed, Embase, Web of Science, etc.) were searched for studies assessing the influence of PFJ degeneration on medial UKA. A random-effects meta-analysis was conducted for the Oxford knee score (OKS), Knee society score (KSS), and revision rates and stratified by PFJ degenerative facets (medial/lateral/trochlear/unspecified), severe PFJ degeneration (bone exposed), and bearing type (mobile/fixed). Heterogeneity was assessed by the Cochran Q test statistic and chi-squared tests with the I-squared statistic. RESULTS: A total of 34 articles with 7007 knees (2267 with PFJ degeneration) were included (5762 mobile-bearing and 1145 fixed-bearing and 100 unspecified). Slight to moderate degenerative changes in the medial and trochlear facets did not decrease the OKS and KSS, and only lateral facets significantly decreased the OKS (mean difference [MD] = -2.18, P   <  0.01) and KSS (MD = -2.61, P   <  0.01). The severity degree of PFJ degeneration had no additional adverse effect on the OKS, KSS, or revision rates. For mobile-bearing UKA, only lateral PFJ degeneration significantly decreased the OKS (MD = -2.21, P  < 0.01) and KSS (MD = -2.44, P  < 0.01). For fixed-bearing UKA, no correlation was found between PROMs/revision rates and PFJ degeneration. CONCLUSION For medial mobile-bearing UKA, slight to moderate degenerative changes in the PFJ, except lateral facet, did not compromise PROMs or revision rates. For medial fixed-bearing UKA, although it might not be conclusive enough, PROMs or revision rates were not adversely affected by PFJ degeneration (regardless of the facet).
Humans ; Arthroplasty, Replacement, Knee ; Patellofemoral Joint/surgery* ; Treatment Outcome ; Osteoarthritis, Knee/surgery* ; Knee Prosthesis ; Bone Diseases ; Knee Joint/surgery* ; Retrospective Studies

OBJECTIVE: To 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. RESULTS: Patients 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). CONCLUSION The 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.
Humans ; Patella/surgery* ; Patellar Dislocation/surgery* ; Patellofemoral Joint/surgery* ; Knee Joint/surgery* ; Joint Dislocations ; Ligaments, Articular/surgery*

Objective: To investigate the changes of imaging parameters of patellofemoral joint after kinematic alignment total knee arthroplasty (KA-TKA) and mechanical alignment total knee arthroplasty (MA-TKA) and the effects on clinical outcomes. Methods: A retrospective analysis was performed on 227 patients diagnosed with knee osteoarthritis, 105 males and 122 females, with the age of (68.6±7.2) years (range: 52 to 86 years). The patients underwent unilateral TKA at the Department of Orthopaedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, from January 2020 to July 2021. The patients were divided into the KA-TKA group (n=102) and the MA-TKA group (n=125) according to the alignment method. The Blackburne-Peel index, lateral patellofemoral angle, patellofemoral tilt angle and patellofemoral index of the two groups were recorded before and 6 months after operation. The frequency of lateral patellar retinaculum release, preoperative and postoperative knee range of motion (ROM), and Oxford knee score(OKS) were also recorded. The differences between preoperative and postoperative measurement data of each group were calculated. If the difference was in line with normal distribution, the independent sample t-test or t'-test was used for comparison between the two groups. If it did not conform to normal distribution, Mann-Whitney U test was used. Paired sample t-test was used for comparison before and after treatment. Chi-square test was used for comparation of categorical data between the two groups. Results: After 6 months of operation, the patellar tilt angles of the KA-TKA group and the MA-TKA group were (14.22±3.26)° and (13.35±2.27)°, and the lateral patellar angles were (9.73±4.86)° and (11.91±3.89)°, respectively. The change of lateral patellofemoral angle in the KA-TKA group was significantly less than that in the MA-TKA group ((1.68±4.86)° vs. (4.15±4.88)°, t=3.805, P<0.01). OKS and ROM were improved in the both groups at 6 months after operation (all P<0.05), but there were no statistic significance in preoperative and postoperative difference between the two groups (all P>0.05). The intraoperative lateral patellar retinacular release rate was 14.4% (18/125) in the MA-TKA group and 6.9% (7/102) in the KA-TKA group, with no statistical difference (χ²=3.256,P=0.071). Conclusions: There are greater patella lateral tilt at 6 months postoperatively in the KA-TKA group compared with the MA-TKA group, but this radiographic difference could not show differences of clinical outcomes and postoperative ROM, the frequency of intraoperative lateral patellar retinacular release wouldn't increase. Therefore, KA-TKA does not increase the difficulty of postoperative patellofemoral joint complications and intraoperative lateral patellar release.
Male ; Female ; Humans ; Middle Aged ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/methods* ; Patellofemoral Joint/surgery* ; Biomechanical Phenomena ; Retrospective Studies ; Patella/surgery* ; Osteoarthritis, Knee/surgery* ; Knee Joint/surgery* ; Knee Prosthesis ; Range of Motion, Articular ; Postoperative Complications

OBJECTIVETo investigate the clinical therapeutic results of allograft tendon for anatomical reconstruction of medial patellofemoral ligament (MPFL) for the treatment of patellar dislocations.

METHODSFrom September 2008 to June 2013, 16 patients with patellar dislocation underwent MPFL reconstructions. There were 2 males and 14 females, aged 11 to 27 years old (16 years old on average). Patellar dislocations occurred in 11 left and 5 right knees. The disease course ranged from 3 to 10 years. The frequency of dislocation ranged from 9 to 33 times (19 times on average). Affected knee joints showed patellar instability; the range of action for patella obviously increased. The X-ray films showed patellar dislocation. The preoperative Q angle was (36 ± 9)°, and the congruence angle was (63 ± 18)°. Reconstruction was performed via allograft tendon. Allograft tendon was fixed through the superomedial pole of the patella, 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 the patients were evaluated postoperatively; Kujala patellofemoral scores, objective knee function, complications, and reoperations were assessed.

RESULTSPrimary healing was achieved in all cases. No infection or necrosis and absorption of grafts was observed. All the patients were followed up for an average of 16.4 months (ranged, 10 to 24 months) postoperatively. At the latest follow-up, all the patients had no pain, swelling and patellar instability; neither patella redislocation nor fracture occurred. The X-ray films showed good position of tunnel 6 months after operation, and the congruence angle was (5 ± 9)°, showing statistically significant difference when compared with preoperation (P < 0.05). The postoperative Q angle was (17 ± 8)°, the Kujala knee function score improved significantly from 45.20 ± 9.20 to 89.30 ± 6.40 at the latest follow-up, showing statistically significant difference (P < 0.05).

CONCLUSIONMPFL reconstruction improves clinical symptoms. Anatomical MPFL reconstruction is effective for patellar dislocation, and it offers good recovery of the premorbid patella mechanics. The interference screw provides firm fixation. Allograft can avoid the graft harvest site morbidity, but it increases the cost of the surgery.

Adolescent ; Adult ; Allografts ; Child ; Female ; Humans ; Ligaments, Articular ; surgery ; Male ; Patellar Dislocation ; surgery ; Patellofemoral Joint ; surgery ; Reconstructive Surgical Procedures ; methods ; Tendons ; transplantation

OBJECTIVETo explore the effectiveness of hamstring tendon graft embedding reconstruction of medial patellofemoral ligament for the treatment of recurrent dislocation of the patella.

METHODSFrom March 2008 to June 2013,67 patients with recurrent dislocation of patella were treated, including 28 males, 39 females with an average age of 22 years ranging from 10 to 42 years old. The clinical manifestations involved knee joint instability,"giving way", sense of patellar dislocation, anterior knee pain. All 67 patients underwent arthroscopic hamstring tendon graft embedding reconstruction of the medial patellofemoral ligament. The curative effect were evaluated by preoperative and postoperative Lysholm score and Q angle changes.

RESULTSAll cases were followed up after operation and the mean follow-up time was(27.5±13.4) months(4 to 69 months). Postoperative incision were healed well and no patellar dislocation or subluxation occurred. Lysholm score improved from preoperative 76.35±2.86 to 82.71±2.29 postoperatively; Q angle decreased from preoperative (18.75±2.33)° to postoperative(13.28±1.75)°.

CONCLUSIONThe method for the reconstruction of medial patellofemoral ligament can provide enough tension, patellar stability.imoroving the function of knee ioint.

Adolescent ; Adult ; Child ; Female ; Humans ; Male ; Patellar Dislocation ; surgery ; Patellar Ligament ; surgery ; Patellofemoral Joint ; surgery ; Reconstructive Surgical Procedures ; methods ; Recurrence ; Tendons ; transplantation

BACKGROUND: Approximately 10% of patients with osteoarthritis (OA) of the knee have unicompartmental OA confined to the patellofemoral joint (PFJ). The main surgical options are total knee replacement (TKR) and PFJ replacement (PFJR). PFJR has a number of advantages over TKR, including being less invasive, preserving the unaffected parts of the knee, allowing faster recovery and better range of motion and function. We report our prospective mid-term results of the Avon PFJR for established isolated PFJ arthritis in 61 consecutive procedures. METHODS: Sixty-one Avon PFJRs were performed in 57 patients. The outcome measures were the new Oxford knee score (OKS), Hungerford and Kenna score (HKS), and Crosby Insall knee scores. Only patients with severe isolated PFJ OA were included. The diagnosis was based on a combination of clinical, radiological and, where available, arthroscopic findings. RESULTS: Mean follow-up was 5.09 years (range, 12 to 124 years). There were 2 revisions in the first 5 years. The median HKS score was 80 (interquartile range, 70 to 95) and the mean OKS was 31.8 (+/- standard deviation, 8.7) at 5 years. These were significantly better (p < 0.001) than the preoperative scores. CONCLUSIONS: The Avon prosthesis gives good functional outcomes in the medium term and survives well. Our data support other studies in the literature and is the largest independent prospective study to date.
Aged ; *Arthroplasty, Replacement, Knee ; Female ; Humans ; Male ; Patellofemoral Joint/*surgery ; Prospective Studies ; Time Factors ; Treatment Outcome

BACKGROUND: Several tendon graft and fixation methods have been introduced in medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar dislocation. The purpose of this study was to evaluate the results of MPFL reconstruction using a gracilis autograft fixation without bone tunnel in patients with recurrent patellar instability. METHODS: Nine patients (four males and five females) diagnosed with recurrent patellar instability from July 2009 to January 2013 and had MPFL reconstruction using a gracilis autograft were included. The average age of the patients was 24.6 years (range, 13 to 48 years), and the average follow-up period was 19.3 months (range, 12 to 30 months). For every patient, femoral attachment was fixed using suture anchors securing the patella by suturing the periosteum and surrounding soft tissue. Clinical evaluation included the Kujala, Lysholm, and Tegner scores; in addition, patients were examined for any complication including recurrent dislocation. The congruence angle and patella alta were assessed radiologically before and after surgery. RESULTS: The Kujala score improved from an average of 42.7 ± 8.4 before surgery to 79.6 ± 13.6 (p = 0.008) at final follow-up; the Lysholm score improved from 45.8 ± 5.7 to 82.0 ± 10.5 (p = 0.008); and the Tegner score improved from 2.8 ± 0.8 to 5.6 ± 1.5 (p = 0.007). The Insall-Salvati ratio changed from 1.16 ± 0.1 (range, 0.94 to 1.35) before surgery to 1.14 ± 0.1 (range, 0.96 to 1.29; p = 0.233) at the final follow-up without significance. The congruence angle significantly improved from 26.5°± 10.6° (range, 12° to 43°) before surgery to -4.0°± 4.3° (range, -12° to 5°; p = 0.008) at final follow-up. Subluxation was observed in one patient and hemarthrosis occurred in another patient 2 years after surgery, but these patients were asymptomatic. CONCLUSIONS: We achieved good results with a patellar fixation technique in MPFL reconstruction using a gracilis autograft employing soft tissue suturing in patients with recurrent patellar dislocation.
Adolescent ; Adult ; *Autografts ; Female ; Humans ; Knee Injuries/radiography/*surgery ; Ligaments, Articular/radiography/*surgery ; Male ; Middle Aged ; Muscle, Skeletal/surgery/transplantation ; Patella/radiography/*surgery ; Patellofemoral Joint/radiography/*surgery ; Reconstructive Surgical Procedures/adverse effects/instrumentation/*methods ; Retrospective Studies ; Thigh/surgery ; Young Adult

BACKGROUNDPatellofemoral osteoarthritis commonly occurs in older people, often resulting in anterior knee pain and severely reduced quality of life. The aim was to examine the effectiveness of arthroscopic patelloplasty and circumpatellar denervation for the treatment of patellofemoral osteoarthritis (PFOA).

METHODSA total of 156 PFOA patients (62 males, 94 females; ages 45-81 years, mean 66 years) treated in our department between September 2012 and March 2013 were involved in this study. Clinical manifestations included recurrent swelling and pain in the knee joint and aggravated pain upon ascending/descending stairs, squatting down, or standing up. PFOA was treated with arthroscopic patelloplasty and circumpatellar denervation. The therapeutic effects before and after surgery were statistically evaluated using Lysholm and Kujala scores. The therapeutic effects were graded by classification of the degree of cartilage defect.

RESULTSA total of 149 cases were successfully followed up for 14.8 months, on average. The incisions healed well, and no complications occurred. After surgery, the average Lysholm score improved from 73.29 to 80.93, and the average Kujala score improved from 68.34 to 76.48. This procedure was highly effective for patients with cartilage defects I-III but not for patients with cartilage defect IV.

CONCLUSIONSFor PFOA patients, this procedure is effective for significantly relieving anterior knee pain, improving knee joint function and quality of life, and deferring arthritic progression.

Aged ; Aged, 80 and over ; Cartilage, Articular ; innervation ; surgery ; Denervation ; methods ; Humans ; Knee Joint ; innervation ; surgery ; Middle Aged ; Osteoarthritis, Knee ; surgery ; Patellofemoral Joint ; innervation ; surgery ; Quality of Life

OBJECTIVETo evaluate the clinical results of the medial patellofemoral ligament (MPFL) reconstruction combined with the lateral retinacular release for the treatment of recurrent patellar dislocation.

METHODSFrom March 2011 to June 2013, 15 patients with recurrent patellar dislocation underwent arthroscopic MPFL reconstruction combined with the lateral retinacular release. The graft was autogenous semitendinosus and semimembranosus tendon. There were 5 males and 10 females with an average age of 19.4 years old (ranged,14 to 32 years old). The patients suffered recurrent patellar dislocation at least twice preoperatively. Preoperative conventional X-ray, CT, and MR examination were used to analyze the causes of the patellofemoral joint and MPFL injury. Preoperative Lysholm score was 69.85 ± 11.52. During operation, the arthroscopic examination was performed to evaluate the patellofemoral alignment and patellar tracking.

RESULTSAll the patients were followed up for an average of 27.6 months (ranged,12 to 36 months) with no recurrent dislocation and sub-dislocation. All the patients showed negative apprehension test at straight and 30 ° flexions of knee. The range of motion of knee returned to normal level at 12 months after operation. There were no patients with subjective discomfort of knee. Postoperative Lysholm score was improved to 92.60 ± 5.75.

CONCLUSIONThe technique of arthroscopic MPFL reconstruction combined with the lateral retinacular release is an effective surgical procedure for the treatment of recurrent patellar dislocation, which can relieve the symptom of knee and improve the patella stability and knee function.

Adolescent ; Adult ; Arthroscopy ; Female ; Humans ; Knee Joint ; surgery ; Male ; Patellar Dislocation ; physiopathology ; surgery ; Patellar Ligament ; physiopathology ; surgery ; Patellofemoral Joint ; physiopathology ; surgery ; Range of Motion, Articular ; Treatment Outcome ; Young Adult

BACKGROUND: Management of the patella during total knee arthroplasty (TKA) is controversial. Multiple studies have examined mechanical and clinical results of TKA with native and resurfaced patellae with no clear consensus. METHODS: We surveyed a large cohort of consultant surgeons in a questionnaire based study in order to assess the indications for patella resurfacing and to correlate practice with degree of specialization, experience and volume of procedures performed. RESULTS: Six hundred and nineteen surgeons were included. The main indication for patella resurfacing was patellofemoral arthritis. The ratio of those who always:sometimes:never resurfaced was 1:2:1 irrespective of experience or volume performed. There was no difference between knee specialists and non-specialists (p = 0.977) or between high and lower volume surgeons (p = 0.826). Senior and high volume surgeons tended to always resurface. CONCLUSIONS: The majority of surgeons only sometimes resurfaced the patella. The number who always and never resurfaced were similar. There was a tendency for more experienced and high volume surgeons to always resurface.
Arthritis/*surgery ; Arthroplasty, Replacement, Knee/*methods/statistics & numerical data ; Cohort Studies ; Great Britain/epidemiology ; Humans ; Knee Joint/*surgery ; Orthopedics/*statistics & numerical data ; Patella/*surgery ; Patellofemoral Joint/surgery ; Questionnaires