Classification and Management of Periprosthetic Patella Fractures.

Complications related to the extensor mechanism and patellofemoral joint continue to be the most common cause of pain and indication for surgical revision following total knee arthroplasty. Numerous risk factors related to the patient, implant, and technical performance of the procedure have been identified. The Ortiguera and Berry classification system is widely used for the systematic classification and management of these fractures. Because of the difficult nature of revision surgery for fracture and the high risk of complication, a careful assessment of the fracture and implants is vital to determining the best course of treatment.

Deformity Reconstruction Surgery for Tibial Hemimelia.

Tibial hemimelia is a rare congenital deficiency with a wide spectrum of pathology and deformity. This paper aims to give a comprehensive review of tibial hemimelia, with a concise summary of the history, pathology, and clinical findings of tibial hemimelia, while providing treatment recommendations and a review of the current literature. Classifications and surgical treatments are discussed, including amputation, limb reconstruction, and lengthening. Type-specific treatments are also discussed, including staged distraction correction of joint contractures of knee and ankle, Weber patelloplasty, fibular centralization, knee and ankle arthrodesis, implantable articulated distractors, and the role of femoral shortening. Amputation is a simpler and easier solution for many patients; however, reconstruction options continue to evolve, improve, and provide better functional outcomes in many cases. Factors favoring surgical reconstruction include the presence of a knee joint/proximal tibia, and the presence of a patella and quadriceps mechanism.

Patellar Rebar Augmentation in Revision Total Knee Arthroplasty.

BACKGROUND: In revision total knee arthroplasty, osteolysis, mechanical abrasion, and infection may leave patellar bone stock severely attenuated with cavitary and/or segmental rim deficiencies that compromise fixation of patellar implant pegs. The purpose of this study was to retrospectively review the use of cortical "rebar" screws to augment cement fixation in revision patelloplasty. METHODS: From 2006 to 2018, dorsal patellar rebar technique was used for patellar reconstruction in 128 of 1037 revision total knee arthroplasty cases (12.3%). Follow-up was achieved with serial radiographs and prospective comparison of Knee Society Scores (KSSs) for clinical outcome. Complications and implant failures requiring reoperation or modified rehabilitation were also assessed. RESULTS: Of the 128 patellar revisions performed using the rebar technique, 69 patients were women and 59 patients were men. The average age of the group was 69.5 years (range, 32-83 years). The mean follow-up of the cohort was 37 months (range, 13-109 months). The most common causes for revision were kinematic conflict, periprosthetic joint infection, and aseptic loosening. The median number of rebar screws used was 5 (range, 1-13). Preoperative KSSs for the study cohort averaged 50 (range, 0-90) At latest follow-up, mean KSS was 85 (range, 54-100). There were 4 patellar-related complications (3.1%) with no implant failures at study conclusion. Retrieval analysis revealed rigid fixation of the reconstructed patellar component in all cases. CONCLUSIONS: Patellar rebar screw augmentation is a useful technique when there are significant cavitary deficiencies and limited segmental rim deficiencies. This technique allows the surgeon to extend indications for patellar revision arthroplasty.

Closed-wedge Patelloplasty for the Treatment of Distal Patellofemoral Maltracking and Instability due to Severe Patellar Dysplasia: Case Report and Surgical Technique.

BACKGROUND: Patellofemoral maltracking is caused by different anatomical factors. Most of them are associated with a proximal maltracking, which alters the patella's engagement into the trochlear groove and predisposes the patellofemoral joint for instability. Different surgical techniques have been described to realign patellar tracking, however, most of which address proximal patellar maltracking. AIM: The aim of this article is to demonstrate the influence of patella-related deformities on patellar tracking and to present a novel surgical technique for the treatment of distal patellar maltracking, caused by a severe patellar dyplasia. CASE DESCRIPTION: We report the case of a 23-year-old patient with a severe patellar dysplasia, presenting a distal patellar maltracking with recurring dislocations in deep flexion. Due to her instability, the patient was immobilised and dependent on the constant use of walking aids. Radiological images showed a concavely shaped patellar, which articulated exclusively with the lateral epicondyle and caused the patella to dislocate laterally, starting at a flexion angle of 60°. An anterior closing-wedge osteotomy was used to reshape and recenter the patella, which was complemented by a medial patellofemoral ligament reconstruction. At the 18-month follow-up, the patient presented pain free and fully remobilised, without the use of walking aids. Patellar tracking was reestablished, with a possible knee flexion until 140°. No redislocation of the patella had occurred. CONCLUSION: Distal patellofemoral maltracking, caused by a severe patellar dysplasia, can successfully be treated with an anterior closed-wedge osteotomy of the patella. In combination with a medial patellofemoral ligament reconstruction, patellofemoral stability can be reestablished, to prevent further dislocations. CLINICAL SIGNIFICANCE: There are multiple factors, which may cause patellar maltracking. A thorough clinical and radiological preoperative analysis is mandatory, in order to clearly identify the underlying pathologies, as these may affect patellar tracking proximally or distally. HOW TO CITE THIS ARTICLE: Frings J, Freudenthaler F, Krause M, et al. Closed-wedge Patelloplasty for the Treatment of Distal Patellofemoral Maltracking and Instability due to Severe Patellar Dysplasia: Case Report and Surgical Technique. Strategies Trauma Limb Reconstr 2020;15(3):184-192.

RETRACTED ARTICLE: Patelloplasty in total knee arthroplasty with circumpatellar denervation versus without denervation - a randomized prospective study.

INTRODUCTION: Anterior knee pain is one of the major problems in total knee arthroplasty (TKA) and is often etiologically associated with a patellofemoral parts etiology. There is no consensus as to etiology or treatment. Denervation of the patella by electrocautery and patelloplasty along with removal of osteophytes have been used for treatment of anterior knee pain in TKA. The purpose of our study was to compare, in terms of the anterior knee pain and clinical outcomes of patelloplasty in total knee arthroplasty (TKA), patellar denervation by electrocautery and non-patellar-denervation treatment in a 2 year follow-up. MATERIALS AND METHODS: This study was conducted in a total of 108 patients, who underwent TKA at our institution between June 2015 and December 2016. Patients age 55 to 80 years, who are suffering from osteoarthritis, rheumatoid arthritis of knee were included in this study. Patients were randomly allocated into patelloplasty with denervation group and non-denervation group. The denervation of the patella was done in electrocautery group using a monopolar coagulation diathermy set to 50 W. (Valleylab Inc., Boulder, CO). Postoperatively, patients were assessed at regular intervals of 3, 6, 9, 12, 24 months. To assess patient outcomes, we used questionnaires to determine the Knee Society score (KSS - knee and function scores), a specific patellofemoral pain questionnaire (Kujala score) range of motion (ROM) and a visual analogue scale (VAS) to assess anterior knee pain. RESULTS: The data obtained were analyzed using SPSS version 17.0. Continuous variables were expressed as mean ± SD. Of the 108 patients, 9 patients were lost to follow-up. Among the remaining 99 patients, 50 were included in denervation group and 49 in non-denervation group. In our study, there was no statistically significant difference in Mean KUJALA score preoperatively (p > 0.05). Postoperatively, the mean KUJALA score was significantly higher in denervation group at 3, 6, 9, 12, 24 months of follow-up when compared to TKR with no denervation (p < 0.05). There was no statistically significant difference in Mean VAS score preoperatively (p > 0.05). However, 6, 12 and 24 months after the operation, the mean VAS score was significantly lower in denervation group. There was no statistically significant difference in Mean KSS score preoperatively and postoperatively (p > 0.05). The mean ROM was significantly higher in denervation group than in the group of TKR with no denervation (p < 0.05). CONCLUSION: In our study, less postoperative anterior knee pain, increased range of motion, significantly lower VAS scores were seen in the denervation group compared with non-denervation group. Circumferential denervation of patella during primary TKA along with patellar resurfacing is a safe procedure that improves patient satisfaction, decreases anterior knee pain and improves range of flexion in the postoperative period and at postoperative follow-ups.

Ignore the Patella in Revision Total Knee Surgery: A Minimum 5-Year Follow-Up With Patella Component Retention.

BACKGROUND: In the setting of aseptic revision, a common question is: what should be done with the previously resurfaced patella? We report on a series of aseptic revision total knee arthroplasties (RTKA) where one or both components were revised and the patella was not. METHODS: The study group was 147 consecutive RTKA in 137 patients with a mean age of 70.1 ± 9.3 years where the patella was not revised. The average body mass index was 31.0 ± 5.4 kg/m2. Follow-up was a minimum of 5 years (range, 5 to 12 years). At final follow-up, 13 patients died and 2 patients were lost to follow-up leaving 122 patients and 130 knees available for review. Mean time from primary surgery to RTKA was 9.2 ± 5.5 years. Both components were revised in 50 knees, the femur only in 11 knees, the tibia only in 12 knees, and 57 had an isolated polyethylene revision. We found 5 patients with a mismatch between the patella and femoral components and 30 cases with patella component wear identified intraoperatively. RESULTS: At final follow-up, there were no reoperations on any patella and none were at risk of failure. There were 6 knees with a lateral patella tilt beyond 10°, but none were subluxed. Knee Society Scores averaged 85 ± 17.2 points at final follow-up. CONCLUSION: At midterm follow-up in this group of RTKA where the patella was not revised, we identified no subsequent failures of the patella. This is despite the presence of mild patella polyethylene wear and mismatched shapes in several knees. LEVEL OF EVIDENCE: III.

The Challenge of Managing the "Third-Space" in Total Knee Arthroplasty: Review of Current Concepts.

Total knee arthroplasty (TKA) is the best treatment for advanced knee osteoarthritis and it has proven to be durable and effective. Anterior knee pain (AKP) is still one of the most frequent complications after TKA, but sometimes no recognized macroscopic causes can be found. The correct treatment of patella is considered the key for a proper management of AKP. The inclusion of patellar resurfacing during TKA has been described as a potential method for the reduction of AKP. After surgeons started to resurface the patella, new complications emerged, such as component failure, instability, fracture, tendon rupture, and soft tissue impingement. Patelloplasty has been proposed as a good alternative to resurfacing but whether or not to resurface the patella is still a controversial topic in the literature. Therefore, patellofemoral joint is a complex critical aspect in TKA and choosing between the several options of treatment of patella could not be sufficient. In this review, evidence-based studies do not succeed in resolving this difficult argument. The accurate management of the so-called "third space" should include an accurate assessment of cartilage layers, balance of soft tissue, preoperative anterior tracking, and positioning of the femoral and tibial components. In fact, the selection of suitable implants and adherence to proper surgical technique are the fundamental principles for the success of TKA.

Treatment for lateral patellar impingement syndrome with arthroscopic lateral patelloplasty: a bidirectional cohort study.

BACKGROUND: Anterior knee pain is one of the most common musculoskeletal complaints of young patients. We notice that some patients had normal femoral trochlear, medial and lateral patellar retinaculum, and special patellar morphology, which resulted in a series of symptoms in the flexion of the knee due to the impingement of the lateral articular surface of the patella with the femur. We firstly termed this pathologic process as lateral patellar impingement syndrome (LPIS). This ambispective cohort study was to explore the curative effect of arthroscopic lateral patelloplasty for early LPIS. METHODS: Thirty-five early LPIS patients which underwent arthroscopic lateral patelloplasty were enrolled in our study. Evaluations consisted of pre- and postoperative symptoms, physical examinations, radiographs, and questionnaires. The Lysholm score, patellar suitable angle, patellar tilt angle, and patellar lateral shift were measured with the CT scan and Merchant X-ray film. The efficacy was graded as excellent, good, fair, and poor according to the patient's subjective evaluation. RESULTS: The patients were followed up for an average of 41.1 ± 18.6 months. The efficacy results were excellent in 6, good in 26, fair in 2, and poor in 1. There were statistical differences in pre- and postoperative Lysholm scores (80.66 ± 5.51 vs 81.91 ± 6.21) (P < 0.05). The pre- and postoperative congruence angle, patellar tilt angle, and patellar lateral shift were significantly different (P < 0.05). CONCLUSIONS: Arthroscopic lateral patelloplasty is an effective and minimal-invasive method for patients with lateral patellar impingement syndrome.

Tibial hemimelia: new classification and reconstructive options.

Tibial hemimelia is a rare congenital lower limb deficiency presenting with a wide spectrum of associated congenital anomalies, deficiencies and duplications. Reconstructive options have been limited, and the gold standard for treatment has remained amputation with prosthetic fitting. There is now a better understanding of the genetics, etiology and pathoanatomy of tibial hemimelia. Armed with this knowledge, I present here a new classification to guide treatment and prognosis and then discuss new treatment strategies and techniques for limb reconstruction based on this new classification scheme.

The role of patelloplasty in total knee arthroplasty.

INTRODUCTION: Anterior knee pain (AKP) is a frequent complication after total knee arthroplasty (TKA). Patelloplasty, defined as reshaping the patella for optimal tracking in the trochlea, has been proposed to reduce the rate of this complication in patellar retaining implants. Aim of this study was to analyze the available literature regarding the outcomes of patelloplasty and to assess its methodological quality. MATERIALS AND METHODS: A comprehensive review of the English literature was performed using the keywords "total knee arthroplasty", "patelloplasty" and "patellaplasty" with no limit regarding the year of publication. All the selected articles were evaluated with the Coleman score. RESULTS: Seven full text articles were retrieved. The initial cohort included 461 knees in the study groups and 465 in the control groups. At an average FU of 70.6 months 447 knees were reviewed in the study group and 447 in the control groups. The global rate of AKP after patelloplasty was 11.3 % which compared to 7.9 % in the patella resurfacing control group. No signs of specific patellar complications due to patelloplasty were reported. Average Coleman score was 66.9. CONCLUSION: Most of the literature has barely sufficient methodological quality. Patelloplasty aims at reducing patellar thickness and improve its tracking with TKA. This procedure is a safe and easy option with no reported adverse effects. In the included studies, outcome seemed to be superior in comparison with isolated osteophyte removal and denervation with a lower rate of AKP. The included studies, however, report a lower rate of AKP following TKA with patellar resurfacing. Patelloplasty may have the potential to improve the outcome of patellar retaining implants. LEVEL OF EVIDENCE: 4, systematic review.

Patellar Nonresurfacing in Total Knee Arthroplasty

PURPOSE: The management of the patella in total knee arthroplasty is still controversy. The purpose of this study was to evaluate clinical and radiological results after total knee arthroplasty without patellar resurfacing. MATERIALS AND METHODS: We retrospective evaluated the nonresurfaced patella in 50 Knees(45 patients) at an average of 65.5 months after total knee arthroplasty(Duracon (R), Howmedica, Rutherford, NJ). Patients were diagnosed as osteoarthritis in 45 and rheumatoid arthritis in 3 and the others were osteonecrosis and evaluated using the knee society knee score, functional knee score and modified patellar score. RESULTS: The mean preoperative knee society knee score in osteoarthritis and rheumatoid arthritis were 58.2 and 36.7 points, and functional score were 35.8 and 34 points. The mean postoperative knee society knee score in osteoarthritis and rheumatoid arthritis were 94.5 and 91.2 points, and functional score were 73.2 and 81 points and the mean modified patellar score was 28.5 points, and 26 cases(52%) were excellent(30-35 points), 18 cases(36%) were good(25-29 points) and 6 cases(12%) were fair(20-24 points). There were no patella-associated complications and in 8 cases(16%) of anterior knee pain, which resolved by a postoperative 4.1 months with conservative treatment. CONCLUSION: Total knee arthroplasty with patelloplasty, without patellar resurfacing , provided satisfactory results without significant problems, and can avoid the patellar complications. But long term radiological and clinical follow-up is recommended.

Total Knee Arthroplasty without patellar resurfacing

Patello-femoral problem is one of the common complications in total knee arthroplasty and whether to replace the patella or retain it has long been controversial in order to prevent the complications. 43 cases (35 patients) of total knee arthroplasty with patellar retention performed by a single surgeon between August 1993 and August 2000 were reviewed retrospectively. The follow-up period averaged 54 months (range, 24-120 months). The whole cases were divided into three groups according to the preoperative radiographs. Group A was normal patella (10 knees), Group B was borderline arthritic patella (20 knees), and Group C was severely deformed patella (13 knees). All of 43 knees, regardless of preoperative radiological degree of arthritis received patelloplasty including removal of osteophytes, subchondral shaving and lateral retinacular release was performed in 20 knees (47%). Each groups was evaluated in terms of the objective criteria of anterior knee pain, range of motion, stair climbing ability, and roentgenographic findings. All 35 patients were diagnosed as osteoarthritis in 29 and rheumatoid arthritis in 6. American Knee Society Score (KSS) was assessed for the clinical analysis and lateral patella shift and patella tilt were assessed for roentgenographic analysis. The mean Knee Society Score at final follow-up was 94 in group A, 93 in group B, and 94 in group C. Mild anterior knee pain was reported in 9.3% (Group A: 2 cases, Group C: 2 cases). patellar tilt was significantly higher in C group (oneway ANOVA test, p=0.01), representing that advanced patello-femoral arthritis caused increased patellar tilt. There was neither significant difference in terms of range of motion, and stair climbing ability nor of patellar shift among all three groups. TKA with patelloplasty, not resurfacing the patella, provided satisfactory results without significant problems regardless of the preoperative degree of patello-femoral arthritis.