Knee Osteoarthritis (OA)
Conditions
Keywords
Knee osteoarthritis, exercise therapy, hip muscle strength, platelet-rich plasma, Hand-held dynamometer, Pain
Brief summary
This single-group longitudinal study evaluated changes in hip stability isometric strength, knee muscle strength, and activity-related pain in women with knee osteoarthritis following a single-dose intra-articular platelet-rich plasma (PRP) injection and a 6-week home exercise program. Outcomes were assessed at baseline (5 days post-injection), week 6, and week 12. The intervention included strengthening exercises for knee and hip muscle groups performed three times per week and regular walking encouragement with weekly phone follow-up for adherence.
Detailed description
Participants with unilateral symptomatic knee osteoarthritis performed a standardized 6-week home strengthening program (knee extensors/flexors; hip extensors/abductors/external rotators) three times weekly and were encouraged to walk regularly. Hip Stability Isometric Test (HipSIT), quadriceps/hamstring strength (hand-held dynamometry, normalized to body mass), and activity pain (VAS 0-10) were measured at baseline, week 6, and week 12 to evaluate functional strength and symptom changes after PRP plus exercise.
Interventions
BIOLOGICALPlatelet-Rich Plasma (PRP) Injection
A single unilateral intra-articular autologous platelet-rich plasma (PRP) injection was administered to the affected knee. Baseline assessments were conducted 5 days following the injection.
BEHAVIORALHome Exercise Program
Home-based exercise program performed 3 times per week for 6 weeks, designed to strengthen knee extensors/flexors and hip extensors/abductors/external rotators. Exercises included: quadriceps strengthening (supine isometric contractions with 5-second hold; seated knee extension with 5-second hold; straight leg raise with 5-second hold), hamstring strengthening (supine isometric contractions with 5-second hold; prone active knee flexion with 5-second hold), hip stabilizer strengthening (clamshells and side-lying hip abduction with 5-second hold), and functional exercises (step-ups, forward touchdowns from a step, side stepping, sit-to-stand from a chair without using arms, and partial wall squats), typically 10-15 repetitions. Participants were also encouraged to walk at least 30 minutes on at least 5 days per week, and adherence was supported via weekly telephone contact.
Sponsors
Firat University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Single Group Assignment
Eligibility
Sex/Gender
FEMALE
Age
45 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Female patients aged 45-70 years. * Radiographic knee osteoarthritis: Kellgren-Lawrence grade II-III in the affected knee and grade II or less in the unaffected knee. * Unilateral knee pain during activity with VAS score ≥5 (for at least the past 3 months). * Referred to physiotherapy following a unilateral single-dose PRP injection.
Exclusion criteria
* Any intra-articular knee injection within the past 6 months. * Regular lower-extremity strengthening exercise or non-pharmacological treatment for knee OA within the past 6 weeks. * History of lower-extremity surgery. * History of neurological, rheumatological and/or cognitive diseases. * Unable to use a telephone.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Hip Stability Isometric Test (HipSIT) strength (N/kg), affected side | Baseline (5 days post PRP injection), Week 6, Week 12 | Hip stability isometric strength (combined hip extensor, abductor and external rotator maximum isometric strength) assessed using a hand-held dynamometer during the Hip Stability Isometric Test (HipSIT). The test is performed in side-lying clam position (hip 45° flexion, knee 90° flexion). Three maximal trials (5 seconds each) are performed and the maximum force output (N) is normalized to body mass (N/kg). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Quadriceps femoris isometric strength (N/kg), affected side | Baseline (5 days post PRP injection), Week 6, Week 12 | Maximum isometric quadriceps strength measured with a hand-held dynamometer in sitting position (hip 90° flexion, knee semi-flexion), with the dynamometer placed on the anterior surface of the ankle. Three maximal trials (5 seconds each) are performed and the maximum force output (N) is normalized to body mass (N/kg). |
| Hamstring isometric strength (N/kg), affected side | Baseline (5 days post PRP injection), Week 6, Week 12 | Maximum isometric hamstring strength measured with a hand-held dynamometer in prone position (hip neutral, knee flexion 90°), with the dynamometer placed on the proximal posterior surface of the ankle. Three maximal trials (5 seconds each) are performed and the maximum force output (N) is normalized to body mass (N/kg). |
| Knee pain during activity (Visual Analog Scale, 0-10) | Baseline (5 days post PRP injection), Week 6, Week 12 | Pain severity during activity assessed using a 10-cm Visual Analog Scale (VAS) ranging from 0 (no pain) to 10 (worst imaginable pain). |
Other
| Measure | Time frame | Description |
|---|---|---|
| Strength symmetry indices (QI, HI, HipI), % | Baseline (5 days post PRP injection), Week 6, Week 12 | Strength symmetry indices calculated as (affected side isometric strength / unaffected side isometric strength) × 100 for HipSIT (HipI), quadriceps (QI), and hamstrings (HI). |
Countries
Turkey (Türkiye)
Outcome results
None listed