Serial Change in Patellar Height after Tension Band Wiring of Patellar Fractures

Background and Objectives: Patella baja is a common complication after operative treatment for patellar fracture. This study aimed to investigate (1) the serial changes in patellar height and (2) the potential predictive factors for patellar height changes after tension band wiring (TBW) for patellar fractures. Materials and Methods: Forty-one patients who underwent TBW for patellar fracture between March 2019 and September 2022 were enrolled. To identify serial changes in patellar height, modified Blackburne-Peel index (mBPI) was assessed at just after surgery, at 3 months, at 6 months, at 1 year and at the final follow-up. Multiple regression analysis was conducted to identify factors correlated with mBPI difference between the contralateral side (considered as preoperative status) and injured side. Results: The postoperative mBPI exhibited a decline over time (mean mBPI immediately post operation/3 months/6 months/1 year/final follow-up: 0.69/0.63/0.63/0.62/0.61) Specifically, mBPI showed a significant reduction immediately post operation to 3 months (p < 0.001), although comparisons at other time points did not reveal significant differences. A lower position of the fracture was associated with a decrease in patellar height after surgery. Conclusions: Patellar height was mainly decreased from immediately post operation to 3 months. A fracture in a lower position of associated with decreased patellar height after the TBW of the transverse patellar fracture.

Challenging Open Extraction of Intraarticular Intracapsular Broken Patellar Cerclage Wire Adjacent to the Medial Femoral Condyle Following Unsuccessful Arthroscopic Removal

Cerclage wiring and tension band wiring are commonly utilized in orthopedic surgeries for patellar fractures, but wire breakage is a recognized complication. This report presents a rare case where a broken cerclage wire exhibited intraarticular intracapsular migration, prompting open removal adjacent to the medial femoral condyle after unsuccessful attempts at arthroscopic extraction. A 50-year-old male with a history of patellar fracture fixation using cerclage and tension band wiring, presented with persistent knee pain and restricted motion. Radiographs revealed a united patellar fracture with a broken cerclage wire, and 3D CT pinpointed the wire fragment in the posterior knee compartment. Arthroscopic removal attempts through standard portals were ineffective, leading to a subsequent open removal via a Burk and Schaffer approach. Intraoperative fluoroscopy guided the thorough dissection, exposing the broken wire deep within the joint capsule, proximal to the intercondylar notch and adjacent to the medial femoral condyle. Meticulous extraction mitigated potential risks of cartilage and neurovascular damage. Follow-up imaging confirmed successful wire removal, and the patient experienced satisfactory functional recovery without significant complications. This case highlights the rare occurrence of intraarticular intracapsular migration of a broken cerclage wire and underscores the importance of timely removal to mitigate risks of cartilage and neurovascular damage. While arthroscopic removal is generally successful, cases of failure may necessitate open extraction, particularly when the wire is located posteriorly. The described approach, assisted by intraoperative fluoroscopy, proved effective in safely removing the broken wire and ensuring optimal patient outcomes.

Decreased Patellar Fractures and Subluxation with Patellar Component Replacement at Stage-One Spacer

BACKGROUND

Periprosthetic joint infection (PJI) is a devastating complication of total knee arthroplasty (TKA) and is often treated with two-stage revision. We retrospectively assessed whether replacing the patellar component with articulating stage-one spacers was associated with improved outcomes compared to spacers without patellar component replacement.

METHODS

A total of 139 patients from a single academic institution were identified who underwent an articulating stage-one revision TKA and had at least 1-year follow-up. Of the 139 patients, 91 underwent patellar component removal without replacement, while 48 had a patellar component replaced at stage-one revision. Patellar fracture and reinfection at any point after stage-one were recorded. Knee range of motion (ROM), patellar thickness, lateral tilt, and lateral displacement were measured at six-weeks post stage-one. Chi-squared, Fisher's exact, and t-tests were utilized for comparisons. There were no significant demographic differences between groups.

RESULTS

Patellar component replacement at stage-one revision was associated with fewer patellar fractures (2.1 versus 12.1%, P = 0.046), less lateral patellar displacement (1.7 versus 16.0 mm, P < 0.01), and improved pre to postoperative knee ROM six weeks after stage-one (+5.9 versus -11.4°, P = 0.03). There was no difference in reinfections after stage-two revision for the replaced or unreplaced patellar groups (15.4 versus 15%, P = 1.000). While the mean time between stage-one and stage-two was not different (5.2 versus 4.5 months, P = 0.50), at one-year follow-up, significantly more patients in the patellar component replacement group were satisfied and refused stage-two revision (45.8% versus 3.3%, P < 0.001).

CONCLUSION

Replacing the patellar component at stage-one revision is associated with a decreased rate of patellar fracture and lateral patellar subluxation, improved ROM, and possible increased patient satisfaction, as reflected by nearly half of these patients electing to keep their spacer. There was no difference in reinfection rates between the cohorts.

Effectiveness of Physical Therapy in a Comminuted Patella Fracture Managed with Tension Band Wiring: A Case Report

A patella fracture occurs when the patella bone, which covers the knee joint, breaks. A severe injury, such as a fall or a hit to the patella, is frequently the cause. There are two types of patella fractures: basic and complicated. The treatment of certain fractures necessitates surgery. Patella fracture symptoms include pain, swelling, bruising, inability to straighten the leg, and inability to walk. Rehabilitation aims to increase the range of motion, increase muscles' strength, and make the patient functionally independent. We report the case of a 69-year-old female with a comminuted patella fracture managed with open reduction and internal fixation (ORIF) with tension band wiring. A four-week inpatient rehabilitation increasing range of motion and improving strength has shown a tremendous improvement in the patient's symptoms.

Knee Extensor Mechanism Complications After Autograft Harvest in ACL Reconstruction: A Systematic Review and Meta-analysis

Background

Existing systematic reviews have sought to characterize the relative donor-site morbidity of bone-patellar tendon-bone (BTB) and quadriceps tendon (QT) grafts after anterior cruciate ligament reconstruction (ACLR). However, no studies have reported the pooled proportions of patellar fractures and donor tendon ruptures across the body of literature.

Purpose

To estimate the proportion of patellar fractures, patellar tendon ruptures, and QT ruptures associated with BTB or QT autograft harvest during ACLR using published data.

Study Design

Systematic review; Level of evidence, 4.

Methods

A meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using 3 online databases (PubMed, Scopus, and Web of Science). A total of 800 manuscripts were included in the initial research of peer-reviewed articles in English that reported extensor mechanism complications associated with graft harvest in patients after ACLR. Pooled proportions of patellar fractures, patellar tendon ruptures, and QT ruptures were calculated for each graft type (BTB, QT) using a random-effects model for meta-analysis.

Results

A total of 28 studies were analyzed. The pooled proportion of patellar fractures was 0.57% (95% CI, 0.34%-0.91%) for the BTB harvest and 2.03% (95% CI, 0.78%-3.89%) for the QT harvest. The proportion of patellar tendon ruptures was 0.22% (95% CI, 0.14%-0.33%) after the BTB harvest, and the proportion of QT ruptures was 0.52% (95% CI, 0.06%-1.91%) after the QT harvest. The majority of included studies (16/28 [57.1%]) had an evidence level of 4.

Conclusion

Based on the current literature, the proportion of extensor mechanism complications after ACLR using either a BTB or a QT autograft is low, indicating that the extensor mechanism harvest remains a safe option. A higher proportion of patellar fractures was noted for QT grafts and a higher proportion of donor tendon ruptures was noted for QT grafts compared with BTB grafts.

Management and Outcome of Elderly Patients With Patellar Fracture Treated With Novel Modified Cerclage Wiring

Introduction

The purpose of this study is to assess the efficacy and security of a fixation method for fixing patellar fractures in elderly patients utilizing modified cerclage wire.

Methods

From January 2015 to December 2020, 31 cases (age≥65 years old) of closed patellar fracture were treated by modified cerclage wiring. Patients in these instances ranged in age from 65 to 87 (73.7 ± 7.2 years), with 15 men and 16 women. 4 instances were type 34-C1 (transverse fracture) according to the AO/OTA classification, 27 cases (87%) were comminuted fractures, including 11 cases that were type 34-C2 (3 fragments), and 16 cases that were type 34-C3 (more than 3 fragments). Postoperative problems such as fragment re-displacement, nonunion, internal fixation loosening, infection, and internal fixation rupture were evaluated. The clinical grading systems of Böstman were used to assess the postoperative clinical outcomes.

Results

Thirty one patients in all were monitored for 14 to 31 months (22.2 ± 4.5 months). After the procedure, the fracture took 2.5-3.5 months (2.92 ± .25 months) to heal. There were no postoperative issues like infection, dislocation, implant breakage, uncomfortable hardware, or post-traumatic osteoarthritis. According to the clinical grading scales of Böstman, the average score of the final follow-up was 28.6 ± 1.1 (range 26-30). 29 (94%) of the patients had excellent results, whereas just 2 (6%) had good results. The patient's knee flexion activity ranged from 110 to 140°, making for a favorable prognosis.

Conclusion

Most patella fractures in the elderly are comminuted. Elderly patients with patellar fractures may be successfully treated with modified cerclage wire, with good results and no noticeable side effects.

A New Antirotation Strategy of K-Wire Tension Band Therapy for Patellar Fracture

Background

Patellar fracture is a common phenomenon observed in orthopedic clinics. Many methods have been shown to be effective in the fixation of patellar fracture. However, there are few studies on the antirotation effect of these methods. The purpose of this study is to present a new strategy of K-wire tension band therapy for patellar fracture and explore the antirotation effect of the modified tension band method on patellar fracture.

Methods

A retrospective clinical observation study was conducted on 75 patients with patellar fracture. Totally, 46 patients were enrolled to the traditional group, who received the traditional K-wire tension band therapy. The modified group included 29 patients on whom our new strategy was implemented. The operation time, intraoperative blood loss, and fracture healing time were collected to compare the two operations and the knee society score (KSS) scores after the operations, and complications were recorded and retrieved to indicate the effectiveness of the two treatments.

Results

The preoperative baseline data (gender, age, fracture types) of the two groups showed no significant statistical difference. Similarly, there was no significant difference in the operation time, intraoperative blood loss, and fracture healing time between the two groups. The KSS clinical scores 1 year after operation was 90 (84, 95) for the traditional group as compared with 99 (97, 100) for the modified group (p < 0.05). The KSS functional scores 1 year after operation in the two groups were 90 (65, 90) and 100 (90, 100) (p < 0.05). The incidences of complications due to the rotation of K-wires in the traditional group and the modified group were 76.1% (35 of 46) and 6.9% (2 of 29) with a significant statistical difference (p < 0.05).

Conclusion

This study shows that our modified tension band therapy is an effective strategy for antirotation in the treatment of patellar fracture and proves that it can achieve better clinical outcomes than the traditional K-wire tension band method. This new strategy may be a safe and effective clinical technique for the treatment of patellar fracture. However, more prospective randomized controlled trials with larger sample sizes are still needed to further prove its efficacy.

[Postoperative outcomes in patients with closed patellar fractures]

OBJECTIVE

To improve postoperative outcomes in patients with closed patellar fractures using a new method of surgical treatment.

MATERIAL AND METHODS

The authors proposed a new method of patellar osteosynthesis. Technique of osteosynthesis is described, and surgical scheme is presented. Treatment outcomes were analyzed in 68 patients with closed patellar fractures. The control group consisted of 34 patients who underwent Weber osteosynthesis. The authors assessed clinical and radiological data. Moreover, clinical example of a patient with traumatic closed patellar fracture and illustrations of surgical treatment are presented.

RESULTS

Clinical data indicate the advantage of treatment in the main group.

Patellar Size Variation at the Quadriceps Tendon-Bone Block Harvest Site: A Magnetic Resonance Imaging Study to Evaluate the Safe Zone for Harvesting a Sufficient Bone Block

BACKGROUND

Quadriceps tendon (QT) autografts with and without a bone block are the least studied and least used options for anterior cruciate ligament reconstruction surgery. In particular, there is a lack of literature describing patellar anatomy. Until now, guidelines for patellar bone block harvesting have been based solely on personal experience. In this study, we intended to derive recommendations from physical regularities and objective criteria.

PURPOSE

To determine the maximal, individual-related length and depth of the bone block that can be safely harvested and to provide guidelines to help surgeons make decisions on graft choice.

STUDY DESIGN

Descriptive laboratory study.

METHODS

The study group consisted of 50 male participants and 50 female participants (mean age, 29.4 ± 7.9 years) who underwent 3.0-T magnetic resonance imaging of their knee. Patellar height was determined at the center of the middle third of the QT insertion on the patella and the medial and lateral endpoints; the depth was measured at the midpoints of the respective heights.

RESULTS

The mean width of the QT and the mean thickness were 49.0 ± 7.6 and 7.3 ± 1.0 mm, respectively. The mean patellar thickness in reference to the medial endpoint, the center, and the lateral endpoint was 18.3 ± 2.4, 17.9 ± 2.3, and 15.1 ± 2.3 mm, respectively, whereas the mean patellar height was 35.1 ± 4.1, 36.7 ± 4.2, and 35.1 ± 3.9 mm. In general, the tendon and patellar dimensions were significantly larger in male participants than in female participants (P = .016).

CONCLUSION

Bone block harvesting, with its depth not exceeding 50% of the patellar thickness and its length accounting for <50% of the patellar height, poses the least risk for a patellar fracture when located medial to midline. If the bone block is excised from the medial half of the central area (the latter is defined by the middle third of the QT insertion), with the outer edge of the saw positioned at the medial border of the central area, a graft of 15 mm length, 10 mm width, and 8 mm depth can be safely harvested in all White male participants and almost all female participants taller than 165 cm, according to our findings.

CLINICAL RELEVANCE

This is the first study presenting recommendations for patellar bone block harvesting at the quadriceps tendon insertionbased on physical regularities and objective criteria and not on personal experience.

Suture Anchor Versus Transosseous Tunnel Repair for Inferior Pole Patellar Fractures Treated With Partial Patellectomy and Tendon Advancement: A Biomechanical Study

Background:

Comminuted inferior pole patellar fractures can be treated in numerous ways. To date, there have been no studies comparing the biomechanical properties of transosseous tunnels versus suture anchor fixation for partial patellectomy and tendon advancement of inferior pole patellar fractures.

Hypothesis:

Suture anchor repair will result in less gapping at the repair site. We also hypothesize no difference in load to failure between the groups.

Study Design:

Controlled laboratory study.

Methods:

Ten cadaveric knee extensor mechanisms (5 matched pairs; patella and patellar tendon) were used to simulate a fracture of the extra-articular distal pole of the patella. The distal simulated fracture fragment was excised, and the patellar tendon was advanced and repaired with either transosseous bone tunnels through the patella or 2 single-loaded suture anchors preloaded with 1 suture per anchor. Load to failure and elongation from cycles 1 to 250 between 20 and 100 N of force were measured, and modes of failure were recorded. Statistical analysis was performed using a paired 2-tailed Student t test.

Results:

The suture anchor group had less gapping during cyclic loading as compared with the transosseous tunnel group (mean ± SD, 6.83 ± 2.23 vs 13.30 ± 5.74 mm; P = .047). There was no statistical difference in the load to failure between the groups. The most common mode of failure was at the suture-anchor interface in the suture anchor group (4 of 5) and at the knot proximally on the patella in the transosseous tunnel group (4 of 5).

Conclusion:

Suture anchors yielded similar strength profiles and less tendon gapping with cyclic loading when compared with transosseous tunnels in the treatment of comminuted distal pole of the patellar fractures managed with partial patellectomy and patellar tendon advancement.

Clinical Relevance:

Suture anchors may offer robust repair and earlier range of motion in the treatment of fractures of the distal pole of the patella. Clinical randomized controlled trials would help clinicians better understand the difference in repair techniques and confirm the translational efficacy in clinical practice.

Patellar Fracture After Total Knee Arthroplasty With Retention: A Retrospective Analysis of 2954 Consecutive Cases

BACKGROUND

To the best of our knowledge, there have been no large case studies on patellar fracture after total knee arthroplasty (TKA) with patella retention.

METHODS

From 2005 to 2019, 2954 consecutive TKAs with patella retention were retrospectively reviewed. The incidence of patellar fracture was confirmed. Perioperative demographic factors associated with patellar fracture were compared between the nonpatellar fracture control (randomly selected after age and sex matching) and patellar fracture patient groups. To confirm the prognosis of identified patellar fractures, Hospital for Special Surgery knee score, union rates, and complications after treatment were evaluated. Treatment outcomes were compared as per the treatment method, and fracture type was classified by shape.

RESULTS

For primary TKAs with patella retention, patellar fracture occurred in 32 of 2883 cases (incidence 1.11%). When comparing the preoperative demographic factors between the patellar fracture and control groups, there was a significant difference in knee flexion of the affected limb. Twenty-three cases were treated nonoperatively, and nine cases were treated operatively. Of the 32 patellar fractures, 28 had confirmed union, and the HSS score at the latest follow-up increased significantly from the preoperative score. The only complication noted after treatment was nonunion in three cases. We found no significant differences in treatment results as per the treatment method and fracture type.

CONCLUSION

Patellar fracture after TKA with retained patella is infrequent, with relatively improved clinicoradiological results over those of patellar fracture after TKA with resurfaced patella reported in the literature. The improved results did not differ as per the treatment method and fracture type.

Application of Three-Dimensional Computed Tomography Improved the Interrater Reliability of the AO/OTA Classification Decision in a Patellar Fracture

We investigated whether interrater reliabilities of the AO/OTA classification of patellar fracture change with the imaging modalities applied, including plain radiography and two- and three-dimensional (2-D and 3-D) computed tomography (CT). Seven orthopedic specialists and four orthopedic residents completed a survey of 50 patellar fractures to classify the fractures according to the AO/OTA classification for patellar fractures. Initially, the survey was conducted using plain radiography only, then with 2-D CT introduced three weeks later and 3-D CT introduced six weeks later. Fleiss’ Kappa coefficients were calculated to determine interrater reliability. The overall interrater reliability of the AO/OTA classifications was 0.40 (95% CI, 0.38–0.42) with plain radiography only and 0.43 (95% CI, 0.41–0.45) with the addition of 2-D CT. With the addition of 3-D CT, the reliability was significantly improved to 0.54 (95% CI, 0.52–0.56). In specialists, interrater reliability of the classifications was moderate with all three imaging modalities. With the use of 3-D CT, interrater reliability of the classification was 0.53 (95% CI, 0.50–0.56), which was significantly higher than that with the use of 2-D CT (κ = 0.45; 95% CI, 0.42–0.48). In residents, interrater reliability of the classification was 0.30 (95% CI, 0.24–0.36) with plain radiography. The reliability improved to 0.49 (95% CI, 0.43–0.56) with the addition of 2-D CT, which was significantly higher than that with plain radiography only. The use of 3-D CT imaging improved interrater reliability of the classification. Therefore, surgeons, especially residents, may benefit from using 3-D CT imaging for classifying and planning the treatment of patellar fractures.

Managing Complications of Patellar Fracture Hardware Removal

A simple surgical procedure is not without the risk of complications and when removing hardware from the bone, such as a previous patella fracture hardware, the surgeon must be well aware of this potential. Here we present the case of a 71-year-old male who presented for removal of retained hardware of united right patella fracture with overlying skin complications. Surgical intervention was uneventful. On post-operative day 1, the patient suffered a fall while using the restroom unassisted with a subsequent large amount of bleeding from the incision site. X-rays demonstrated a new displaced inferior pole patellar fracture. The patient returned to the operating room for debridement and repair of this new patellar fracture with primary closure. Intraoperative cultures of initial operative site were positive for Corynebacterium and Staphylococcus epidermidis. The patient was then started on intravenous Vancomycin based on culture sensitivities. The patella fixation/repair was protected with a knee immobilizer as there was increased risk of falls due to his age/underlying medical condition. This case discusses recommendations and guidelines for preventing and managing these various postoperative complications.

Small, Short, Oblique Patellar Tunnels for Patellar Fixation Do Not Increase Fracture Risk or Complications in MPFL Reconstruction: A Retrospective Cohort Study

Background:

Large (4.5 mm) and/or transpatellar bone tunnels have been associated with patellar fracture after medial patellofemoral ligament (MPFL) reconstruction. To avoid this outcome, many surgeons now employ suture anchors to affix the MPFL graft to the patella.

Purpose:

To evaluate the risk of patellar fracture and other outcomes associated with smaller (3.2-mm), short, oblique patellar tunnels as compared with suture anchor fixation in MPFL reconstruction.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A single institution’s electronic medical record was queried for all patients undergoing MPFL reconstruction between March 2010 and December 2018. A chart review of operative reports was utilized to identify those who had undergone MPFL reconstruction. Patients undergoing revision MPFL reconstruction or reconstruction with fully transpatellar bone tunnels were excluded. The incidence of patellar fracture and outcomes were evaluated from chart review. The mean duration of follow-up was >2 years.

Results:

A total of 384 knees in 352 patients undergoing primary MPFL reconstruction were identified. Small (3.2-mm), short, oblique tunnels were used for patellar fixation in 215 cases, and suture anchors were utilized in 169 cases. The small, oblique tunnels and suture anchor techniques both resulted in a low incidence of patellar fracture, with rates of 0.47% and 0%, respectively. The use of suture anchors was associated with an increased risk of subluxation or dislocation compared with small, oblique tunnels (odds ratio, 3.98; P = .028). No significant difference was found in the need for revision MPFL reconstruction surgery with suture anchors (odds ratio, 1.925; P = .66).

Conclusion:

The use of small, oblique tunnels with hamstring autograft is a safe means of patellar fixation in MPFL reconstruction. The use of small, oblique tunnels for patellar fixation versus 2 suture anchors can result in material cost savings with no significantly increased risk for fracture as well as an overall reduction in complication rates.

Patellar Sleeve Fracture in an Eight-Year-Old Girl

The patellar sleeve fracture is a rare entity in pediatric traumatology. Its diagnosis is challenging due to its rarity and subtle radiographic finding, and it is easily missed by emergency physicians. Early recognition and treatment of this fracture is of paramount importance in order to guarantee better outcomes. We present herein a case of severely displaced patellar sleeve fracture in an eight-year-old girl, which was treated successfully by open reduction and fixation of the osteochondral fragments using anchor sutures, yielding very positive clinical outcomes at the two-year follow-up.

The modified anterior ellipsoidal cap titanium cable tension band for comminuted patellar fractures

PURPOSE

The purpose of this study was to assess the outcomes in a series of patients, who underwent cerclage and figure-of-eight tension band wiring using a single titanium cable for comminuted patellar fractures.

METHODS

We describe a modified tension band technique using a single titanium cable to create an ellipsoidal cap structure that combines the circumferential and figure-of-eight wrapping in the fixation of closed Association for the Study of Internal Fixation/Orthopaedic Trauma Association 34C2 and 34C3 patellar fractures. We retrospectively reviewed 25 patients (16 males and 9 females, mean age 54 years) who underwent the described fixation technique between 2015 and 2017. Postoperative function was evaluated using the Böstman score.

RESULTS

At the mean follow-up of 25 months (range 17-39 months), the mean Böstman score was 27.3 ± 2.6 points (range 23-30). Eighteen patients (72%) had excellent results (score ≥28); seven patients (28%) had good results (score 20-27); and no patients had an unsatisfactory result (score < 20). All surgical incisions healed without major wound complications. Two patients reported minor complications (soft tissue irritation, cellulitis). No patients demonstrated loss of reduction or implant failure during the follow-up period.

CONCLUSION

The modified anterior ellipsoidal cap tension band using a single titanium cable created an effective tension band structure in the treatment of comminuted patella fractures. It is a simple operative technique that produced a stable fixation construct, which allowed early functional rehabilitation and weight-bearing with a high rate of excellent outcomes at 2 years after surgery.

Modified tension band wiring of patellar fracture as a technique to minimize postoperative complications: A case report

RATIONALE

Tension band wiring is the most widely accepted technique for the treatment of patellar fractures but the technique is associated with common complications like wire migration, prominence, and breakage. To reduce these complications, we developed and propose a modified technique that has a superior biomechanical strength and a potential to reduce such postoperative complications.

PATIENT CONCERNS

The patient presented with pain and mild swelling in his left knee after he slipped on the floor and fell on his left knee. He has no significant past medical or surgical history. The patient took the tension band wiring as the first choice because of the wide acceptance. But he worried about the complications.

DIAGNOSES

X-ray showed a transverse fracture of the left patella with an inferior pole occult fracture.

INTERVENTIONS

The patient was operated with a modified technique of the classic tension band wiring for patellar fractures. In our 4-step procedure, double tension cerclage wires were wrapped under the exposed ends of the Kirschner wires (K-wires) and the tendons in figure-of-8 fashion. The aim was to increase the biomechanical strength so that when one of the tension wires fail, the other one can hold the fragments together.

OUTCOMES

The patient recovered very well and without any complications. The patient was followed-up for 1 year and the fracture has united very well, with satisfying knee range of motion.

LESSONS

From this case study, we can detect the biomechanical advantages of our technique which can increase the stability of the fracture and that allows early functional exercise and additionally the micromotion at the fracture site has a beneficial effect of fracture union. Based on the perfect outcomes, our technique is worthy of clinical application.

Clinical Outcomes After Medial Patellofemoral Ligament Reconstruction With Suture Fixation of the Gracilis Tendon via Transosseous Tunnels

Background:

Several fixation methods have been introduced in medial patellofemoral ligament (MPFL) reconstruction. However, the optimal management of patients with recurrent patellar dislocation remains controversial.

Purpose:

To present a case series with a minimum 2-year follow-up of 29 patients with recurrent patellar dislocation who underwent a new transosseous suture fixation technique for MPFL reconstruction.

Study Design:

Case series; Level of evidence, 4.

Methods:

From January 2014 through February 2016, a total of 29 patients with recurrent patellar dislocation for which the MPFL was reconstructed with transosseous suture patellar fixation were studied. All patients were available for follow-up (mean, 37.52 months; range, 26-48 months). The patellar attachment was fixed by transosseous patellar sutures. The International Knee Documentation Committee (IKDC) subjective knee score, Kujala score, Tegner score, range of motion, congruence angle, patellar tilt angle, and complications were assessed both pre- and postoperatively.

Results:

No recurrent dislocation was observed in any of the 29 patients for a minimum of 2 years. All outcome scores improved significantly from preoperatively to postoperatively: the average IKDC subjective knee evaluation score from 53 to 87, Kujala from 54 to 90, Lysholm from 50 to 89, and Tegner from 3 to 5 (P < .001 for all). The congruence angle significantly decreased from 22° preoperatively to –3° postoperatively, and the patellar tilt angle (Merchant) decreased from 23° preoperatively to 5° postoperatively (P < .001 for both). In total, 25 patients (25/29; 86.21%) were completely pain-free when performing activities of daily living at the last follow-up, and 27 patients (93.1%) rated themselves as very satisfied or satisfied with the results.

Conclusion:

In patients with chronic recurrent patellar dislocation, transosseous patellar suture fixation for MPFL reconstruction can significantly improve patellar stability and achieve good results at short-term follow-up.

Increased Patellar Fracture Rate in Total Knee Arthroplasty With Preoperative Varus Greater Than 15°: A Case-Control Study

BACKGROUND

Management of severe varus deformity requires soft tissue balancing for implantation of low-constraint knee prosthesis. Patellar complications have been rarely studied in this specific group. Our hypothesis was that severe genu varum (>15°) would increase the rate of patellar complications.

METHODS

Using a prospective cohort of 4216 prostheses performed at a single center beginning in 1987, we analyzed 280 prostheses having preoperative varus greater than 15°, compared to 673 total knee arthroplasties (TKAs) with a preoperative hip-knee-ankle angle of 180° ± 2°. Preoperative and postoperative clinical and radiological characteristics were compared between the 2 groups, with particular attention paid to patellar complications.

RESULTS

Average follow-up was 40.2 months (24-239). The mean preoperative Knee Society Score (KSS) was statistically higher in the normal (hip-knee-ankle angle 180° ± 2) axis group (62.65 vs 37.47, P = .001). At the last follow-up, no significant difference was found between the 2 groups in terms of postoperative KSS (87.5 in the varus group vs 87.3 in the normal axis group, P = .87). The rate of satisfied patients was identical between the 2 groups (85.3% vs 88.8%, P = .49). However, at mid-term, there were more patellar fractures in the varus group (2.9% vs 0.9%, P = .005). A significantly lower patellar height in both the varus group and the group of patella fractures (P < .001) was also found.

CONCLUSION

TKA in severe varus knees produces a KSS equivalent to TKA in knees with a mechanical axis of 0 ± 2. The risk of patellar fracture could initiate a decline in patella resurfacing in patients with major varus deformation, especially in case of a preoperative patella baja.

Surgery of patellar fractures using a medial parapatellar approach

PURPOSE

The general surgical approach for patellar fractures has a significant weakness, in that the articular facet is invisible because the fixation is performed using radiation amplifiers after exposing the fracture site through vertical or transverse dissection on the anterior patella. We report excellent outcomes in the surgical treatment of patellar fractures, using a medial parapatellar approach.

METHODS

This study evaluated 20 patients who underwent surgery between August 2008 and April 2014 to correct patellar fractures with comminution or with displacement of the articular facet of ≥2 mm and who had ≥1 year of follow-up. Surgery was performed using anatomical reduction with direct exposure of the articular facet of the patella via a medial parapatellar approach. Bone union, severity of displacement, range of motion (ROM) of the patella, and complications were evaluated after surgery, and patellar function was evaluated using the Lysholm knee score.

RESULTS

Bone union was achieved in all cases, and average displacement of the articular facet decreased from 3.2 mm (range: 1.2-7.3 mm) preoperatively to 0.2 mm (range: 0-0.5 mm) postoperatively. No particular postsurgical complication was observed. All cases had a normal ROM, and the average Lysholm score at final follow-up was 96.2 points.

CONCLUSION

Anatomical fixation of the articular facet via a medial parapatellar approach appears to be suitable for patellar fractures, which are intra-articular.

Management of patellar fracture with titanium cable cerclage

Early rehabilitation after surgery for patellar fracture is challenging. The purpose of this study was to evaluate the surgical outcome of titanium cable cerclage for patellar fracture in early functional activity.We reviewed a series of 24 patients treated at our hospital with titanium cable. Functional exercises were started early. Patients were followed up for at least 12 months.Fifteen were males and 9 were females. Fracture occurred in the right knee in 13 patients and in the left knee in 11 patients. The most common mode of injury involves a tumble. None of the patients presented with any postoperative complications. The management resulted in satisfactory outcomes.Titanium cable cerclage offers a new strategy in treating patellar fracture.

Comparison of titanium cable tension band and nickel-titanium patella concentrator for patella fractures

BACKGROUND

Patellar fractures account for approximately 1% of all fractures. Due to the patella's importance as regards the extensor mechanism, effort should be made to preserve the patella. Several operative treatment methods have been introduced for patella fractures.

OBJECTIVES

This study aims to compare the clinical effect of a titanium cable tension band and nickeltitanium (NiTi) patella concentrator (NT-PC) in treating patella fractures.

MATERIAL AND METHODS

Thirty-nine patients with patella fractures were enrolled in this retrospective study. All the patients were treated via the open reduction internal fixation procedure using a titanium cable tension band or NT-PC. All the patients were followed up over an average period of 13 months. The main outcome measures were operation time, time of fracture union, postoperative complications, and Böstman knee scores. Statistical analyses were conducted between the 2 groups.

RESULTS

All the patients were operated on successfully. The operation time of the NT-PC treatment group was less than that of the titanium cable tension band treatment group (p < 0.05). The mean scores at the final follow-up were 28.2 and 27.6 points in the titanium cable tension band and NT-PC groups, respectively. No significant difference was observed between the excellent and good results (p > 0.05).

CONCLUSIONS

Both titanium cable tension band and NT-PC showed good efficacy for the treatment of patellar fractures. NT-PC fixation, a new option for the treatment of patella fractures, is a simple and effective fixation method.

Biodegradable poly-L-lactide-co-glycolide copolymer pin fixation of a traumatic patellar osteochondral fragment in an 11-year-old child: A novel surgical approach

Treating displaced patellar bone fractures in growing children remains a challenge for orthopedic surgeons. Removal of loose bone fragments may prolong healing time and result in early onset osteoarthrosis. Therefore, primary fixation of osteochondral fragments is preferred. Metallic pin and screw implants are typically used for fixation, as there is little evidence available regarding the use of modern biodegradable implants in traumatic patellar fractures of a premature skeleton. The present report describes a novel operative technique using headless poly-L-lactide-co-glycolide (PLGA) pins in treating an 11-year-old girl with a patellar fracture from a cycling injury. The surgical technique of this procedure is described in detail in the current report. Excellent subjective outcomes were achieved from this surgery, with superb bone healing according to follow-up radiographic and computerized tomography scans. In conclusion, the results of this case indicate that, similarly to osteochondritis, intra-articular osteochondral fractures in children may be fixed using biodegradable PLGA pins. Randomized clinical trials should be performed to confirm this finding and evaluate the use of PLGA pins as a treatment for adolescent osteochondral fractures.

The Use of Dual Reconstruction Plates for Failed Fixation of Patellar Fracture after Total Knee Replacement: A Case Report

Patellar fracture after total knee replacement (TKR) is one of the challenging problems in periprosthetic fracture. Open reduction with internal fixation (ORIF), as tension band wiring (TBW), usually required in cases with extensor mechanism disruption. However, many studies reported a high failure rate after using this technique. In this report, we presented an interesting case of periprosthetic patellar fracture after TKR with TBW failure that was successfully treated with double non-locking reconstruction plates fixation and TBW augmentation.

Clinical results of treatment using a modified K-wire tension band versus a cannulated screw tension band in transverse patella fractures: A strobe-compliant retrospective observational study

It was a retrospective case-control study. The aim of this study was to explore the clinical efficacy and complication of treatment using a modified Kirschner wire tension band (MKTB) or a cannulated screw tension band (CSTB) in transverse patellar fractures.In total, 55 patients with transverse patellar fractures were retrospectively reviewed and divided into 2 groups according to the surgical technique: 29 patients were in the MKTB group and 26 patients in the CSTB group. B[Latin Small Letter o with Caron]stman's clinical grading scale, including range of movement (ROM), pain, ability to work, atrophy of quadriceps femoris, assistance in walking, effusion, giving way, and stair-climbing, was used to evaluate the clinical results. Complications including painful hardware, implant loosening or breakage, and bone nonunion were also assessed.Both groups were evaluated at the final follow-up before removing implant in the MKTB group. The B[Latin Small Letter o with Caron]stman's score of ROM, pain, atrophy of quadriceps femoris, and effusion were all higher in the CSTB group than in the MKTB group (P < 0.05). Twelve patients in the MKTB group underwent implant removal, and the score of ROM, pain, and effusion were higher than before removing implant (P < 0.05), but there was no difference compared to the CSTB group (P > 0.05). Seventeen patients achieved excellent results, 9 had good results, and 3 reported fair results in the MKTB group; the CSTB group had excellent results in 22 patients and good results in 4 patients, showing a significant difference in the excellent rate between the 2 groups (P = 0.021). Total B[Latin Small Letter o with Caron]stman scores in the MKTB and CSTB groups (26.96 ± 4.47 and 29.42 ± 1.47, respectively) were significantly different (P = 0.01). Total scores in the MKTB group after removing implant were higher than those before removing implant (P = 0.001), and similar to those in the CSTB group (P = 0.224). Eleven patients in the MKTB group reported painful hardware, including 4 cases of implant loosening.CSTB achieves better clinical results than MKTB, meanwhile avoiding the problems of painful hardware and implant loosening. Functional limitation caused by hardware pain was commonly seen in the MKTB group, and removing implant after fracture healing improved knee function.

Current concepts review: Fractures of the patella

Fractures of the patella account for about 1% of all skeletal injuries and can lead to profound impairment due to its crucial function in the extensor mechanism of the knee. Diagnosis is based on the injury mechanism, physical examination and radiological findings. While the clinical diagnosis is often distinct, there are numerous treatment options available. The type of treatment as well as the optimum timing of surgical intervention depends on the underlying fracture type, the associated soft tissue damage, patient factors (i.e. age, bone quality, activity level and compliance) and the stability of the extensor mechanism. Regardless of the treatment method an early rehabilitation is recommended in order to avoid contractures of the knee joint capsule and cartilage degeneration.

For non-displaced and dislocated non-comminuted transverse patellar fractures (2-part) modified anterior tension band wiring is the treatment of choice and can be combined – due to its biomechanical superiority – with cannulated screw fixation. In severe comminuted fractures, open reduction and fixation with small fragment screws or new angular stable plates for anatomic restoration of the retropatellar surface and extension mechanism results in best outcome. Additional circular cerclage wiring using either typical metal cerclage wires or resorbable PDS/non-resorbable FiberWires increases fixation stability and decreases risk for re-dislocation. Distal avulsion fractures should be fixed with small fragment screws and should be protected by a transtibial McLaughlin cerclage. Partial or complete patellectomy should be regarded only as a very rare salvage operation due to its severe functional impairment.

Patellar resurfacing complications in total knee arthroplasty

PURPOSE

The ideal management of the patella during total knee arthroplasty (TKA) is still controversial. Patellar retention is generally associated with an increased rate of anterior knee pain; however, patient satisfaction is similar in cases of replacement or retention. When the patella is replaced, potential severe complications can occur. Aim of this study was to retrospectively review results of a continuous series of patients having been treated with TKA and patella resurfacing.

METHODS

The charts of 1,600 consecutive total knee prostheses were analysed to evaluate the rate of patellar resurfacing. All implants were posterior stabilized; 310 patients having received a patellar replacement were reviewed at follow-up (FU) examination. Complete physical examination as well as administration of the Hospital for Special Surgery (HSS) score was performed. X-rays analysis included weightbearing anteroposterior (AP) and lateral views of the injured knee and bilateral skyline views at 30° flexion.

RESULTS

Two hundred and eighty patients were available for clinical and imaging investigation at an average FU of 96 (58-144) months. Mean age at the time of surgery was 70 (62-80) years. Mean HSS score was 85.9 ± 7.6. The overall rate of patellofemoral complications was 7% (19 cases); 13 patients claimed anterior knee pain, five had symptomatic patellar maltracking and one had patellar component loosening.

CONCLUSION

Our data are in accordance with those available in the literature. Recent meta-analyses demonstrated lower risk of re-operation after patellar resurfacing. However, when complications of the resurfaced patella occur, they can be potentially catastrophic events.

Biomechanical studies on transverse olecranon and patellar fractures: a systematic review with the development of a new scoring method

INTRODUCTION

Several methods of transverse patellar and olecranon fixation have been described. This article compares biomechanical studies of various fixation methods using a newly developed scoring method.

SOURCE OF DATA

The databases PubMed, Web of Science, Science Direct, Google Scholar and Google were searched for relevant studies.

AREAS OF AGREEMENT

Fixation hardware failure remains a problem. Various materials and fixation techniques have been tested to provide an improved fixation of transverse olecranon and patellar fractures.

AREAS OF CONTROVERSY

The difference in biomechanical testing setup between the studies makes it hard to compare different fixation techniques.

GROWING POINTS

The newly developed grading method was proved to be unbiased and reliable; however, extra specifications need to be added at some criteria when adopting the scoring method.

AREAS TIMELY FOR DEVELOPING RESEARCH

Non-metallic constructs may provide an improvement to the currently used metallic tension band wiring technique; however, clinical research is required.

Treatment of transverse patellar fractures: a comparison between metallic and non-metallic implants

INTRODUCTION

Several methods of transverse patellar fixation have been described. This study compares the clinical outcome and the occurrence of complications of various fixation methods.

SOURCES OF DATA

The databases PubMed, Web of Science, Science Direct, Google Scholar and Google were searched.

AREAS OF AGREEMENT

A direct comparison between fixation techniques using mixed or non-metallic implants and metallic K-wire and tension band fixation shows no significant difference in clinical outcome between both groups. Additionally, studies reporting novel operation techniques show good clinical results.

AREAS OF CONTROVERSY

Studies describing the treatment of patients using non-metallic or mixed implants are fewer compared with those using metallic fixation.

GROWING POINTS

A large variety of clinical scoring systems were used for assessing the results of treatment, which makes direct comparison difficult.

AREAS TIMELY FOR DEVELOPING RESEARCH

More data of fracture treatment using non-metallic or mixed implants is needed to achieve a more balanced comparison.