[Patellar fractures]

High return to sports rates after operative treatment of patella fractures

BACKGROUND

Patella fractures are relatively rare fractures and only little is known about the postoperative return to sports after patella fractures.

METHODS

This retrospective study presents information on functional outcome after operative treatment of patella fractures as well as time until return to sports and patients' complaints after open-reduction internal-fixation (ORIF) of patella fractures.

RESULTS

Overall, 39 patients after ORIF of patella fractures were evaluated at our Level-I trauma center with a mean follow-up of 42 months. The mean time until return to sports was 7 ± 3.9 months. No significant difference was found for functional outcome with respect to body mass index (BMI) or age. Fracture consolidation was accomplished after a mean of 6.9 ± 2.9 months besides a relatively low complication rate of 5.1% (n = 2).

CONCLUSION

The results demonstrate a high return to sports rate of 90.3%. However, only 51.6% were able to perform sports on their pre-injury level or above. Trial Registration The study was retrospectively registered at DRKS (No: DRKS00031146).

Tension-band wiring through a single cannulated screw combined with suture anchors to treat inferior pole fracture of the patella

PURPOSE

To evaluate the feasibility and clinical outcomes of tension-band wiring through a single cannulated screw combined with two suture anchors in treating inferior pole fracture of the patella.

METHODS

Between September 2018 and September 2021, a total of 22 patients with a mean age of 55 years who sustained inferior pole fracture of the patella and were treated by tension-band wiring through a single cannulated screw combined with two suture anchors were enrolled. X-ray radiographs were performed to observe the bone union time. The duration of each operation was recorded to reflect the complexity of surgical treatment. Functional measurements, comprising range of motion (ROM), the Böstman scale, and the Knee Injury and Osteoarthritis Outcome Score (KOOS), were taken. Postoperative complications including fixation failure, incision infection, loss of reduction, and malunion were evaluated.

RESULTS

All patients were followed up for an average of 17 months (range: 12-25 months). The average clinical bone union time was 8 weeks (range: 6-12 weeks), and the radiographic bone union time was 11 weeks (range: 8-12 weeks). At the final follow-up, the mean ROM was 136° (range: 115°-140°), the KOOS was 85 (range: 68-100) and the Böstman score was 28 (range: 20-30); these outcomes were classified as excellent in 17 cases and good in 5 cases, with no instances of poor results. Loss of reduction occurred in one case, while no cases of incision infection, fixation failure or malunion were observed.

CONCLUSION

For inferior pole fracture of the patella, tension-band wiring through a single cannulated screw combined with suture anchors can offer sufficient fixation stability to achieve a satisfactory clinical outcome with reduced operational complexity; this procedure should be recommended in clinical practice.

Anterior Locking Plate Osteosynthesis of Patellar Factures - Analysis of Complications and Functional Outcome

BACKGROUND

Tension band wiring is the standard procedure for patellar fractures, but is associated with a high rate of implant related complications and implant failure. Tension band wiring may fail, especially with multifragmentary and comminuted fractures. Plate fixation of complex patellar fractures seems to be superior to wiring, both clinically and biomechanically. The aim of this study was to evaluate complications after locking plate fixation in patellar fractures two years after surgery and to access the functional outcome.

MATERIAL AND METHODS

As part of a prospective case series, all patients who had received locking plate fixation of a patellar fracture between April 2013 and May 2018 were clinically examined two years postoperatively and potential complications were evaluated.

RESULTS

A total of 38 patients aged 19 - 87 years were included. Complications occurred in a total of five patients (13%), including one reactive prepatellar bursitis, one chronic infection and loss of reduction due to a dislocated pole fragment in three cases. The average active range of motion of the affected knee joint two years postoperatively was 133°. The Tegner activity scale score reached 3 points, the Lysholm score 95 points and the Kujala score 95 points.

CONCLUSION

With an overall relatively low complication rate and good clinical outcome, dislocated distal pole fragments are a common complication after plate fixation of patellar fractures. If preoperative diagnostic testing shows a pole fragment, a modified hook-plate can be used, with the possibility of fixing the pole fragment.

[Osteosynthetic treatment of a periprosthetic patellar fracture : A case report]

This case report describes the successful fixation of a periprosthetic patellar fracture in an 89-year-old female patient after total knee arthroplasty (TKA) and cemented retropatellar component. Fixation was performed by use of a fixed-angle plate combined with cerclage, under preservation of the firmly fixed retropatellar prosthetic component. No complications were observed postoperatively. Radiologic controls confirmed bone healing. A range of movement of the knee joint of 0/5/110° was achieved by the last clinical examination 5 years postoperatively. The patient was free of pain and had an age-appropriate mobility. The use of fixed-angle plates in the treatment of type II periprosthetic patellar fractures according to Ortiguera and Berry can provide stable fixation while preserving the retropatellar prosthetic component. Additional augmentation by cerclage, tapes or traction screws is recommended in cases of poor bone stock or severe osteoporosis.

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.

Interventions for treating fractures of the patella in adults

BACKGROUND

Fractures of the patella (kneecap) account for around 1% of all human fractures. The treatment of these fractures can be surgical or conservative (such as immobilisation with a cast or brace). There are many different surgical and conservative interventions for treating fractures of the patella in adults. This is an update of a Cochrane Review first published in 2015.

OBJECTIVES

To assess the effects (benefits and harms) of interventions (surgical and conservative) for treating fractures of the patella in adults.

SEARCH METHODS

We searched CENTRAL (2020, Issue 1), MEDLINE, Embase, LILACS, trial registers and references lists of articles to January 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs that evaluated any surgical or conservative intervention for treating adults with fractures of the patella. The primary outcomes were patient-rated knee function, knee pain and major adverse outcomes.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected eligible trials, assessed risk of bias and cross-checked data extraction. Where appropriate, we pooled results of comparable trials.

MAIN RESULTS

We included 11 small trials involving 564 adults (aged 16 to 76 years) with patella fractures. There were 340 men and 212 women; the gender of 12 participants was not reported. Seven trials were conducted in China and one each in Finland, Mexico, Pakistan and Turkey. All 11 trials compared different surgical interventions for patella fractures. All trials had design flaws, such as lack of assessor blinding, which put them at high risk of bias, potentially limiting the reliability of their findings. No trial reported on health-related quality of life, return to previous activity or cosmetic appearance. The trials tested one of seven comparisons. In the following, we report those of the main outcomes for which evidence was available for the three most important comparisons. Four trials (174 participants) compared percutaneous osteosynthesis versus open surgery. Very low-quality evidence means that we are uncertain of the findings of no clinically important difference between the two interventions in patient-rated knee function at 12 months (1 study, 50 participants) or in knee pain at intermediate-term follow-up at eight weeks to three months. Furthermore, very low-quality evidence means we are uncertain whether, compared with open surgery, percutaneous fixation surgery reduces the incidence of major adverse outcomes, such as loss of reduction and hardware complications, or results in better observer-rated knee function scores. Two trials (112 participants) compared cable pin system (open or percutaneous surgery) versus tension band technique. The very low-quality evidence means we are uncertain of the findings at one year in favour of the cable pin system of slightly better patient-rated knee function, fewer adverse events and slightly better observer-rated measures of knee function. There was very low-quality evidence of little clinically important between-group difference in knee pain at three months. Very low-quality evidence from two small trials (47 participants) means that we are uncertain of the findings of little difference between biodegradable versus metallic implants at two-year follow-up in the numbers of participants with occasional knee pain, incurring adverse events or with reduced knee motion. There was very low-quality and incomplete evidence from single trials for four other comparisons. This means we are uncertain of the results of one trial (28 participants) that compared patellectomy with advancement of vastus medialis obliquus surgery with simple patellectomy; of one quasi-RCT (56 participants) that compared a new intraoperative reduction technique compared with a standard technique; of one quasi-RCT (65 participants) that compared a modified tension band technique versus the conventional AO tension band wiring (TBW) technique; and of one trial (57 participants) that compared adjustable patella claws and absorbable suture versus Kirschner wire tension band.

AUTHORS' CONCLUSIONS

There is very limited evidence from nine RCTs and two quasi-RCTs on the relative effects of different surgical interventions for treating fractures of the patella in adults. There is no evidence from trials evaluating the relative effects of surgical versus conservative treatment or different types of conservative interventions. Given the very low-quality evidence, we are uncertain whether methods of percutaneous osteosynthesis give better results than conventional open surgery; whether cable pin system (open or percutaneous surgery) gives better results than the tension band technique; and whether biodegradable implants are better than metallic implants for displaced patellar fractures. Further randomised trials are needed, but, to optimise research effort, these should be preceded by research that aims to identify priority questions.

[Current treatment standard for patella fractures in Germany]

BACKGROUND

The treatment of patella fractures is technically demanding. Although the radiological results are mostly satisfactory, this often does not correspond to the subjective assessment of the patients. The classical treatment with tension band wiring with K‑wires has several complications. Fixed-angle plate osteosynthesis seems to be biomechanically advantageous.

OBJECTIVE

Who is treating patella fractures in Germany? What is the current standard of treatment? Have modern forms of osteosynthesis become established? What are the most important complications?

MATERIAL AND METHODS

The members of the German Society for Orthopedics and Trauma Surgery and the German Knee Society were asked to participate in an online survey.

RESULTS

A total of 511 completed questionnaires were evaluated. Most of the respondents are specialized in trauma surgery (51.5%), have many years of professional experience and work in trauma centers. Of the surgeons 50% treat ≤5 patella fractures annually. In almost 40% of the cases preoperative imaging is supplemented by computed tomography. The classical tension band wiring with K‑wires is still the preferred form of osteosynthesis for all types of fractures (transverse fractures 52%, comminuted fractures 40%). In the case of comminuted fractures 30% of the surgeons choose fixed-angle plate osteosynthesis. If the inferior pole is involved a McLaughlin cerclage is used for additional protection in 60% of the cases.

DISCUSSION

The standard of care for patella fractures in Germany largely corresponds to the updated S2e guidelines. Tension band wiring is still the treatment of choice. Further (long-term) clinical studies are needed to verify the advantages of fixed-angle plates.