Tension Band Versus Locking Plate Fixation for the Treatment of Patella Fractures (TENPLA)

TENSION BAND VERSUS LOCKING PLATE FIXATION FOR THE TREATMENT OF PATELLA FRACTURE - a High Quality, Multicenter, Randomized Clinical Trial

Aarhus University Hospital, Randers Regional Hospital, Regional Hospital Hjoerring, Regional Hospital Kolding, Viborg Regional Hospital

This study is a multicenter pragmatic, prospective, assessor-blinded, randomized independent clinical trial in which we compare locking plate fixation to standard tension band fixation in patients with patella fractures.

This study is a multicenter pragmatic, prospective, assessor-blinded, randomized independent clinical trial in which we compare locking plate fixation to standard tension band fixation in patients with patella fractures. Primary objective The overall objective of the study is to compare the 1-year patient-reported Knee Injury and Osteoarthritis Outcome Score (KOOS5) after standard tension band fixation with locking plat fixation for patients with patella fractures. Secondary objectives Several other analyses are of interest and are planned but are not objectives of this study. Therefore, these analyses will, for the major part, hypothesis-generating. Analyses of this type include, but are not limited to harms, muscle atrophy, pain, general health, gait function, time to return to work and economical consequences between the two groups.

This study is a multicenter pragmatic, prospective, assessor-blinded, randomized independent clinical trial

Due to the surgical nature of the study the surgeon can not be blinded. The outcome assessor, patients and care providers will be blinded with regards to the two treatment groups.

Surgical fixation of the patella fracture utilizing the AO principles using K-wires, screws, cerclage and sutures by surgeons choice.

Surgical fixation of the patella fracture utilizing the AO principles and a locking plate with the number of screws by surgeons choice. Additional fixation by surgeons choice.

The Knee Injury and Osteoarthritis Outcome Score (KOOS) 29 is a standardised patient-reported questionnaire developed to evaluate knee problems. The questionnaire includes five subscales: pain, ADL, symptoms, sport and QOL and an overall score KOOS5 can be calculated. A total score of 100 indicates no symptoms, and 0 indicates major symptoms.

The Knee Injury and Osteoarthritis Outcome Score (KOOS) 29 is a standardised patient-reported questionnaire developed to evaluate knee problems. The questionnaire includes five subscales: pain, ADL, symptoms, sport and QOL and an overall score KOOS5 can be calculated. A total score of 100 indicates no symptoms, and 0 indicates major symptoms.

The Knee Injury and Osteoarthritis Outcome Score (KOOS) 29 is a standardised patient-reported questionnaire developed to evaluate knee problems. The questionnaire includes five subscales: pain, ADL, symptoms, sport and QOL and an overall score KOOS5 can be calculated. A total score of 100 indicates no symptoms, and 0 indicates major symptoms.

General health will be assessed using EQ-5D-5L questionnaire (5-level version), both the descriptive index and the EQ-VAS. It consists of five dimensions: Mobility, self-care, usual activities, pain/discomfort and anxiety/depression, and a self-rated health scale on a 20 cm vertical, visual analogue scale with endpoints labelled 'the best health you can imagine' and 'the worst health you can imagine'. An Eq5d-5L index of 1.0 indicated full health, 0 death, and -0.59 denoted a condition worse than death.

Development in pain will be recorded by patient-reported pain intensity measured on a 10 cm visual analogue scale (VAS) with endpoints "no pain" and "maximal pain" for the worst pain during the last 24 hours and resting pain.

Knee pain and neuropathic pain will be assessed using the "PainDETECT" questionnaire. The "PainDETECT" screening questionnaire uses a scoring method between 1-38. A total score of 1 indicates no symptoms, and 38 indicates major symptoms.

Bone union, will be evaluated on standard AP and side X-rays of the fractured patella. The evaluation of bone union will be defined as: i) visible callus formation, diminished no visible fracture line and no pain from the fracture site at weight-bearing and at clinical examination.

Maximum isometric knee-extension strength at 60 degrees knee flexion measured as Nm/kg body mass. Will be measured bilaterally by a strap-mounted dynamometer attached to the wall (Mecmesin AFG2500, Mecmesin Ltd, West Sussex, UK)

Maximum isometric knee-flexion strength at 90 degrees knee flexion measured as Nm/kg body mass. Will be measured bilaterally by a strap-mounted dynamometer attached to the wall (Mecmesin AFG2500, Mecmesin Ltd, West Sussex, UK)

Knee range of motion. With the patient supine on an examination table the full range of passive motion in both knee joints will be measured using a standard goniometer.

Adverse events, defined as any negative or unwanted reactions to the two groups will be recorded. Based on previous reports we will focus on: infection, DVT and re-operation. Patients are continuously requested to report any suspicion of a potential AE. Furthermore, adverse events (AE) will be recorded at 3-, 6- and 12-months follow-up by asking patients about potential AEs using open-probe questioning to ensure that all AEs are recorded. Furthermore, medical records will be checked at the primary endpoint (12 months) for all AEs occurring from inclusion until the 12 months follow-up. An AE is defined as any undesirable experience during follow-up leading to contact with the healthcare system (general practitioner or hospital). If an AE result in hospitalization, prolonged inpatient hospital care, result in re-surgery, or if an AE is life-threatening, result in death, permanent disability or damage, they will be categorized as serious adverse events (SAEs).

Inclusion Criteria: Above 18 years of age Patella fracture suitable for surgically treatment, with both surgical methods AO classification 34-B, 34-C Exclusion Criteria: Open patella fracture above Gustillo grade 2 Bilateral patella fracture Total knee replacement in the affected extremity Other fractures of the affected extremity within the previous 12 months. Other reasons for exclusion (unable to understand Danish, mentally unable to participate, etc). Prior ipsilateral patella fracture

A detailed statistical analysis plan will be made publicly available before the last patient is included in the study.

https://vbn.aau.dk/ws/portalfiles/portal/410910476/Protokol_patella_multicenter_final_version_16042021.pdf