An observational study in Closed Proximal Tibial Fracture Schatzker I - VI, Closed Proximal Tibial Fracture AO-OTA 41 and Closed Proximal Tibial Fracture AO-OTA 42, sponsored by Synthes GmbH. Completed at 2 sites in Korea, Republic of. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-03-03.
Sponsored by Synthes GmbH (part of Johnson & Johnson) · Observational
The primary objective of this study is to observe the safety, the radiological and clinical outcomes of chronOS Inject after having been used as bone void filler in internal fixation of proximal tibial fractures.
The primary objective of this study was to observe the safety, the radiological and clinical outcomes of chronOS Inject after having been used as bone void filler in internal fixation of proximal tibial fractures. Secondary objectives were to assess the surgeon's satisfaction in using chronOS Inject and patient satisfaction post surgery.
The study was planned to be a multi-center, prospective, observational study. Patients with proximal tibial fractures of type Schatzker I - VI, AO-Müller-Orthopaedic Trauma Association (AO-OTA) 41, AO-OTA 42 with bone defect were assessed for eligibility to enter the study. Patients eligible for the study were followed over time to twelve months after surgery.
135 studies on the registry are indexed under Tibial Fractures; 37 are open to participants now.
This study's enrollment of 36 is below the median of 70 across 37 observational studies indexed under Tibial Fractures.
Browse Tibial Fractures studies →Synthes GmbH is the lead sponsor of 10 studies on the registry; none are open to participants now.
First submitted after Synthes GmbH became part of Johnson & Johnson.
Counted across the registry records on this site, refreshed daily.
Patients with proximal tibial fractures of type Schatzter I - VI, AO-OTA 41, AO-OTA 42 with bone defect are assessed for eligibility to enter the study. A computerized tomography is performed if necessary to confirm the fracture type and the amount of bone defect. Patients eligible for the study are followed over time to 12 months after surgery.
A total of 30 patients who meet the inclusion/exclusion criteria are enrolled in the study, which is conducted at Kyungpook National University Hospital and Hanyang University Guri Hospital in the Republic of Korea.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Closed proximal tibial fractures of type Schatzker I - VI, AO-OTA 41, AO-OTA 42 with bone defect
Device: chronOS Inject
chronOS Inject is used as bone void filler in internal fixation of proximal tibial fractures
Fracture Union
Fracture union (complete bone healing) was assessed by the investigators based on anteroposterior and lateral X-rays
Time frame: 12 months
Articular Subsidence
Evidence of articular subsidence (collapse of surface pertaining to the joint) of ≥2 mm was assessed by the investigators
Time frame: 12 months
Mean Time to Union
Mean time to union was calculated based on the Kaplan-Meier estimator of the survivorship function
Time frame: 12 months
Absorption Rate of Calcium Phosphate Cement
Absorption of calcium phosphate cement over time was calculated from X-rays with the INFINITT program.
Time frame: 12 months
Patients Who Reached Full Weight Bearing
Time frame: 12 months
Total Range of Motion
Time frame: 12 months
Anatomical Gradings Assessed Radiographically
The following was assessed: * depression of knee joint: presence or absence * condylar widening (enlargement of the knee joint): presence or absence * angulation; valgus/varus (abnormal outward/inward turning of the knee): presence or absence
Time frame: 12 months
Patient's Satisfaction
Satisfaction with treatment was assessed by the subjects, where subjects indicated their satisfaction with treatment on a 100-mm visual analog scale. A score of zero indicated no satisfaction, while a score of 100 indicated completely satisfied.
Time frame: 12 months
Surgeon's Satisfaction With the Product
Satisfaction with product was assessed by the surgeon post-operatively, where surgeons indicated their satisfaction with treatment on a 100-mm visual analog scale. A score of zero indicated absolutely unacceptable, while a score of 100 indicated very satisfying.
Time frame: Post-surgery
Extension Ability and Stability
The following was assessed: * extension ability of the knee * stability of the knee in extension
Time frame: 12 months
Peri-operative Complications
Time frame: 12 months
SF-12 Short Form Health Survey Physical Composite Score (PCS)
The SF-12 short form health survey was self-administered to subjects preoperatively and all follow up visits. This health survey comprises 12 questions related to health and wellbeing over the prior four weeks. The responses to these 12 questions are entered into a standardized algorithm to provide summaries of physical and mental health (i.e., physical composite score \[PCS\] and mental composite score \[MCS\]). The summary scores are standardized and normalized such that a score of 50 for either the PCS or MCS corresponds to that of an average, healthy person. A score lower than 50 indicates poorer physical and mental health compared to an average, healthy person.
Time frame: 12 months
SF-12 Short Form Health Survey Mental Composite Score (MCS)
The SF-12 short form health survey was self-administered to subjects preoperatively and at follow up visits. This health survey comprises 12 questions related to health and wellbeing over the prior four weeks. The responses to these 12 questions are entered into a standardized algorithm to provide summaries of physical and mental health (i.e., physical composite score \[PCS\] and mental composite score \[MCS\]). The summary scores are standardized and normalized such that a score of 50 for either the PCS or MCS corresponds to that of an average, healthy person. A score lower than 50 indicates poorer physical and mental health compared to an average, healthy person.
Time frame: 12 months
VAS Leg Pain Intensity
The subjects completed questionnaires assessing the intensity and frequency of pain experienced in the leg at the baseline visit and postoperatively. Pain intensity was rated on a 100-mm visual analog scale where zero indicated no pain at all, and 100 represented the worst possible pain.
Time frame: 12 months
VAS Leg Pain Frequency
The subjects completed questionnaires assessing the intensity and frequency of pain experienced in the leg at the baseline visit and postoperatively. Pain frequency was rated on a 100-mm visual analog scale where zero indicated no pain at all and 100 represented pain always.
Time frame: 12 months
Lysholm Knee Scale
The Lysholm knee scale is a condition-specific outcome measure that was originally designed to assess ligament injuries of the knee. The survey was administered to subject at follow-up visits and comprises 8 subscales related to limp, support, stair climbing, squatting, walking, running and jumping as well as a question related to the atrophy of the thigh. The responses to these 8 questions are graded to provide a maximum result of 100 points.
Time frame: 12 months
| Milestone | chronOS Inject |
|---|---|
| Started | 36 |
| 6 weeks | 34 |
| 6 months | 31 |
| Completed | 29 |
| Not completed | 7 |
| Withdrew: Lost to follow-up | 7 |
Fracture union (complete bone healing) was assessed by the investigators based on anteroposterior and lateral X-rays
| participants | chronOS Inject |
|---|---|
| Union | 27 |
| Non-union | 2 |
Evidence of articular subsidence (collapse of surface pertaining to the joint) of ≥2 mm was assessed by the investigators
| participants | chronOS Inject |
|---|---|
| Absent | 28 |
| Present | 1 |
Absorption of calcium phosphate cement over time was calculated from X-rays with the INFINITT program.
| percentage of absorption at 12 months | chronOS Inject |
|---|---|
| Absorption Rate of Calcium Phosphate Cement | 0.64 ± 0.115 |
| participants | chronOS Inject |
|---|---|
| Patients Who Reached Full Weight Bearing | 29 |
| participants | chronOS Inject |
|---|---|
| At least 140 degree | 17 |
| At least 120 degree | 11 |
| At least 90 degree | 1 |
| At least 60 degree | 0 |
| At least 30 degree | 0 |
The following was assessed: * depression of knee joint: presence or absence * condylar widening (enlargement of the knee joint): presence or absence * angulation; valgus/varus (abnormal outward/inward turning of the knee): presence or absence
| participants | chronOS Inject |
|---|---|
| Absence of depression | 28 |
| Absence of condylar widening | 28 |
| Absence of angulation | 29 |
Satisfaction with treatment was assessed by the subjects, where subjects indicated their satisfaction with treatment on a 100-mm visual analog scale. A score of zero indicated no satisfaction, while a score of 100 indicated completely satisfied.
| units on a scale | chronOS Inject |
|---|---|
| Patient's Satisfaction | 80.52 ± 16.02 |
Satisfaction with product was assessed by the surgeon post-operatively, where surgeons indicated their satisfaction with treatment on a 100-mm visual analog scale. A score of zero indicated absolutely unacceptable, while a score of 100 indicated very satisfying.
| units on a scale | chronOS Inject |
|---|---|
| Mixing ability | 87.3 ± 6.16 |
| Injecting ability | 87 ± 6.31 |
| Application time | 87 ± 6.31 |
| Moldability | 81.7 ± 9.59 |
| Setting time | 77.1 ± 13.54 |
| Rate of chronOS over bone graft | 68.6 ± 28.39 |
The following was assessed: * extension ability of the knee * stability of the knee in extension
| participants | chronOS Inject |
|---|---|
| Normal extension ability | 26 |
| 0-10 degree extension ability | 3 |
| Normal extension stability | 28 |
| Abnormal extension stability | 1 |
| participants | chronOS Inject |
|---|---|
| Microscopic or radiologic cement leakage during OP | 0 |
| Breakage of fixing device post-OP | 0 |
| Re-OP during hospital stay | 0 |
| Suffer from surgical wound complication post-OP | 0 |
The SF-12 short form health survey was self-administered to subjects preoperatively and all follow up visits. This health survey comprises 12 questions related to health and wellbeing over the prior four weeks. The responses to these 12 questions are entered into a standardized algorithm to provide summaries of physical and mental health (i.e., physical composite score \[PCS\] and mental composite score \[MCS\]). The summary scores are standardized and normalized such that a score of 50 for either the PCS or MCS corresponds to that of an average, healthy person. A score lower than 50 indicates poorer physical and mental health compared to an average, healthy person.
| units on a scale | chronOS Inject |
|---|---|
| Score at baseline | 37.02 ± 9.616 |
| Score at 12 months | 42.43 ± 4.589 |
The SF-12 short form health survey was self-administered to subjects preoperatively and at follow up visits. This health survey comprises 12 questions related to health and wellbeing over the prior four weeks. The responses to these 12 questions are entered into a standardized algorithm to provide summaries of physical and mental health (i.e., physical composite score \[PCS\] and mental composite score \[MCS\]). The summary scores are standardized and normalized such that a score of 50 for either the PCS or MCS corresponds to that of an average, healthy person. A score lower than 50 indicates poorer physical and mental health compared to an average, healthy person.
| units on a scale | chronOS Inject |
|---|---|
| Score at baseline | 46.3 ± 9.707 |
| Score at 12 months | 46.45 ± 7.145 |
The subjects completed questionnaires assessing the intensity and frequency of pain experienced in the leg at the baseline visit and postoperatively. Pain intensity was rated on a 100-mm visual analog scale where zero indicated no pain at all, and 100 represented the worst possible pain.
| units on a scale | chronOS Inject |
|---|---|
| Score at baseline | 61.19 ± 32.714 |
| Score at 12 months | 17 ± 18.592 |
The subjects completed questionnaires assessing the intensity and frequency of pain experienced in the leg at the baseline visit and postoperatively. Pain frequency was rated on a 100-mm visual analog scale where zero indicated no pain at all and 100 represented pain always.
| units on a scale | chronOS Inject |
|---|---|
| Score at baseline | 57.28 ± 33.505 |
| Score at 12 months | 20.52 ± 20.051 |
The Lysholm knee scale is a condition-specific outcome measure that was originally designed to assess ligament injuries of the knee. The survey was administered to subject at follow-up visits and comprises 8 subscales related to limp, support, stair climbing, squatting, walking, running and jumping as well as a question related to the atrophy of the thigh. The responses to these 8 questions are graded to provide a maximum result of 100 points.
| participants | chronOS Inject |
|---|---|
| Excellent (95-100) | 14 |
| Good (84-94) | 11 |
| Fair (65-83) | 3 |
| Poor (<65) | 1 |
Mean time to union was calculated based on the Kaplan-Meier estimator of the survivorship function
| months | chronOS Inject |
|---|---|
| Mean Time to Union | 7.5 ± 0.441 |
Collected over Adverse events were recorded from treatment (implantation of the device) through the end of the follow-up period at 12 months.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| chronOS Inject | — | 1/36 (2.8%) | 9/36 (25%) |
| Event | chronOS Inject |
|---|---|
| Non-union of lateral tibial condyleMusculoskeletal and connective tissue disorders | 1/36 |
| Event | chronOS Inject |
|---|---|
| K-wire irritationSkin and subcutaneous tissue disorders | 3/36 |
| Back painMusculoskeletal and connective tissue disorders | 2/36 |
| Volar mass on finger (MP joint)Musculoskeletal and connective tissue disorders | 1/36 |
| Articular subsidence, loss of reduction and depression of lateral condyle of the tibiaMusculoskeletal and connective tissue disorders | 1/36 |
| PainGeneral disorders | 1/36 |
| Cartilage damage at the initial injuryMusculoskeletal and connective tissue disorders | 1/36 |
| Posterior neck painMusculoskeletal and connective tissue disorders | 1/36 |
| Non-union of lateral tibial condyleMusculoskeletal and connective tissue disorders | 1/36 |
| Age, Continuous(years) | chronOS Inject |
|---|---|
| Mean | 55.4 ± 14.6 |
| Age, Customized(participants) | chronOS Inject |
|---|---|
| Age group <=58 years | 19 |
| Age group >58 years | 17 |
| Sex: Female, Male(Participants) | chronOS Inject |
|---|---|
| Female | 15 |
| Male | 21 |
| Race (NIH/OMB)(Participants) | chronOS Inject |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 36 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 0 |
| White | 0 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Region of Enrollment(participants) | chronOS Inject |
|---|---|
| Korea, Republic of | 36 |
| Smoking status(participants) | chronOS Inject |
|---|---|
| Never | 23 |
| Former | 4 |
| Current | 9 |
| Height(cm) | chronOS Inject |
|---|---|
| Mean | 163.4 ± 8.99 |
| Weight(kg) | chronOS Inject |
|---|---|
| Mean | 62.6 ± 12.15 |
8 further baseline measures are reported on the registry.
Ran from Mar 2010 to primary completion in Sep 2012, 30 months.
Results were first posted in Jun 2014, 1 year 8 months after primary completion.
Of 17 observational studies under Tibial Fractures, half reached primary completion within 41 months of starting (the median), counting those still running; a quarter within 33 and three quarters within 62. This study's 30 months is below that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Feb 2025. You cannot join it, but the record below documents what was studied.
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