Functional Hip Strength Improvement in Knee Osteoarthritis Following Single-Dose PRP and a 6-Week Home Exercise Program

Functional Hip Strength and Pain Changes in Women With Knee Osteoarthritis Following a Single-Dose Intra-Articular Platelet-Rich Plasma Injection and a 6-Week Home Exercise Program: A Single-Group Longitudinal Study

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.

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.

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.