Anterior Knee Pain, Patellar Tendon Disorder, Tibial Shaft Fractures
Conditions
Keywords
Tibial intramedullary nailing, Infrapatellar tendon split, Patellar tendon elasticity, Shear-wave elastography, Anterior knee pain, Tibial shaft fracture
Brief summary
This prospective single-center observational cohort study will evaluate the relationship between anterior knee pain and patellar tendon elasticity after infrapatellar tendon-split tibial intramedullary nailing. Adult patients undergoing standard tibial intramedullary nailing through an infrapatellar tendon-split approach will be enrolled after ethics approval. Patellar tendon elasticity will be assessed using shear-wave ultrasound elastography before surgery and during follow-up at 6 weeks, 3 months, and 6 months. Clinical outcomes will include anterior knee pain severity, patellofemoral function, tendon-related symptoms, and knee range of motion. Inter-rater reliability between two independent radiologists will also be evaluated.
Detailed description
Anterior knee pain is a frequent complaint after tibial intramedullary nailing, but the role of patellar tendon biomechanical changes remains unclear. The infrapatellar tendon-split approach may lead to tendon healing, remodeling, and fibrosis, which could alter tendon elasticity and contribute to persistent pain and functional limitation. This study aims to prospectively investigate whether changes in patellar tendon elasticity are associated with anterior knee pain after infrapatellar tendon-split tibial intramedullary nailing. This is a prospective, single-center, non-interventional observational cohort study. Adult patients aged 18 to 65 years with unilateral tibial shaft or metaphyseal fractures treated with standard infrapatellar tendon-split tibial intramedullary nailing will be enrolled consecutively after institutional ethics approval. Only patients enrolled after ethics approval will be included in the registered cohort. Patellar tendon elasticity will be measured using shear-wave ultrasound elastography at four predefined time points: preoperatively, 6 weeks, 3 months, and 6 months postoperatively. Ultrasound assessments will be performed according to a standardized protocol by two independent radiologists, and inter-rater reliability will be assessed. Additional ultrasound parameters will include tendon thickness on B-mode imaging and Doppler neovascularization. Clinical outcomes will include anterior knee pain assessed with a visual analog scale, patellofemoral function assessed with the Kujala Anterior Knee Pain Scale, tendon-related symptoms assessed with the VISA-P questionnaire, pressure pain sensitivity, and active knee range of motion. The primary objective is to determine whether change in patellar tendon elasticity is associated with anterior knee pain at 6 months. Secondary objectives are to examine associations between tendon elasticity and functional scores, range of motion, tendon thickness, Doppler findings, and inter-rater measurement reliability.
Interventions
PROCEDUREInfrapatellar tendon-split tibial intramedullary nailing
Standard-of-care tibial intramedullary nailing performed through an infrapatellar longitudinal patellar tendon split approach. The procedure is not assigned by the protocol; only patients undergoing this routine surgical approach are observed.
DIAGNOSTIC_TESTShear-wave ultrasound elastography
Non-invasive shear-wave ultrasound elastography of the patellar tendon performed at predefined study visits using a standardized imaging protocol.
Sponsors
Bagcilar Training and Research Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Age 18 to 65 years * Unilateral tibial shaft or metaphyseal fracture * Planned treatment with infrapatellar tendon-split tibial intramedullary nailing * Ability to complete baseline and follow-up assessments * Written informed consent
Exclusion criteria
* Previous surgery on the same knee * Previous patellar tendon rupture or known patellar tendon disorder * Active inflammatory rheumatologic disease * Chronic systemic corticosteroid therapy or long-term immunosuppressive treatment * Significant peripheral neuropathy or advanced diabetic neuropathy * Bilateral tibial fracture * Additional major lower-extremity injury or surgery affecting assessment * Inability to comply with scheduled follow-up visits
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in patellar tendon elasticity from baseline to 6 months | Preoperative baseline and 6 months postoperatively | Patellar tendon elasticity measured by shear-wave ultrasound elastography in kilopascals. The primary analysis will assess the longitudinal change from baseline to 6 months. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Patellar Tendon-Related Symptoms and Function | Preoperative baseline, 3 months, and 6 months | Patellar tendon-related symptoms and function will be assessed using the Victorian Institute of Sport Assessment-Patella questionnaire. The questionnaire ranges from 0 to 100 points, with higher scores indicating fewer patellar tendon-related symptoms and better function |
| Active knee range of motion | Preoperative baseline, 6 weeks, 3 months, and 6 months | Active knee flexion and extension lag measured with a goniometer. |
| Patellar tendon thickness | Preoperative baseline, 6 weeks, 3 months, and 6 months | Patellar tendon thickness measured on B-mode ultrasound. |
| Doppler neovascularization | Preoperative baseline, 6 weeks, 3 months, and 6 months | Semiquantitative Doppler neovascularization score. |
| Pressure Pain Sensitivity | 6 weeks, 3 months, and 6 months | Pressure pain sensitivity will be assessed by recording pain intensity during a standardized pressure pain assessment using the Visual Analog Scale. The Visual Analog Scale ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pressure pain sensitivity. |
| Inter-rater reliability of shear-wave elastography measurements | Baseline, 6 weeks, 3 months, and 6 months | Agreement between two independent radiologists assessed using intraclass correlation coefficients. |
| Change in patellar tendon elasticity from baseline to 3 months | Preoperative baseline and 3 months postoperatively | Change in patellar tendon elasticity measured by shear-wave ultrasound elastography. |
| Patellofemoral function | Preoperative baseline, 3 months, and 6 months | Patellofemoral function will be assessed using the Kujala Anterior Knee Pain Scale. The scale ranges from 0 to 100 points, with higher scores indicating better patellofemoral function and fewer anterior knee symptoms. |
| Anterior knee pain severity | Baseline and postoperative 6 weeks, 3 months, and 6 months | Anterior knee pain severity will be assessed using the Visual Analog Scale. The Visual Analog Scale ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate worse anterior knee pain. |
Countries
Turkey (Türkiye)
Outcome results
None listed