Here is a thorough clinical breakdown for this patient:
Clinical Assessment: Right-Sided Waist/Flank & Back Pain After a Fall
Patient Summary
- Female patient
- History: Fall in January - treated with injection, massage, and paracetamol (PCM)
- Current complaint: Right-sided waist (flank) pain, now recurring with sitting, sometimes radiating to the spine/back area
Most Likely Differential Diagnoses
1. Lumbar Muscle Strain (Most Common)
The original fall likely caused a muscle strain in the right paraspinal or quadratus lumborum muscles. The key issue here is that the injury was not fully rehabilitated - LBP recurs in up to 80% of patients within one year when functional rehabilitation is incomplete. Sitting for long periods aggravates this because it loads the lumbar muscles unevenly.
Signs: Tenderness over paraspinal muscles, worsened with prolonged sitting or bending, no neurological symptoms.
2. Lumbar Facet Joint Syndrome
Found in up to 35% of low back pain cases. The fall in January could have injured the right lumbar facet joints. Patients feel unilateral back pain that increases with back extension and lateral rotation toward the painful side. Pain can radiate to the hip/thigh but not below the knee. Straight leg raise (SLR) test is negative.
3. Sacroiliac (SI) Joint Syndrome
A very common cause of one-sided lower back/waist pain, especially after a fall trauma. Pain is on one side of the low back, may radiate to the hip or thigh. The Patrick's test (FABER test) will be positive. Pain often worsens when climbing stairs.
4. Lumbar Disc Herniation
The initial fall may have caused a disc injury that was partially managed but is now recurring. If disc herniation is present, pain typically:
- Shoots down the leg (radiates to foot/toes) - L4/L5 or L5/S1
- SLR test positive
- May have numbness or weakness in the leg
Since she currently only has waist and spine-area pain (no leg radiation mentioned), this is possible but less likely at this stage.
5. Kidney/Renal Cause (Important to Rule Out)
Right-sided flank pain at the waist level can also come from the right kidney - kidney stones, urinary tract infection (UTI), or pyelonephritis. These causes are NOT related to the injury but must be excluded.
Red flags for kidney cause:
- Pain comes in waves (colicky)
- Burning during urination
- Fever, chills
- Nausea/vomiting
- Pain not affected by position or movement
Clinical Red Flags to Check Immediately
These need urgent evaluation if present:
- Leg weakness or numbness
- Loss of bladder or bowel control
- Fever
- Unexplained weight loss
- Pain at night that wakes her from sleep
Recommended Assessment Steps
| Step | Action |
|---|
| History | Ask about leg radiation, urinary symptoms, fever, night pain |
| Physical Exam | Paraspinal tenderness, SLR test, Patrick's/FABER test, SI joint tenderness, percussion over kidneys (costovertebral angle tenderness) |
| Urine test | Urinalysis + urine culture to rule out UTI/kidney stone |
| Imaging | X-ray lumbar spine (AP + lateral) as first step; MRI if neurological signs or no improvement |
| Blood test | CBC, ESR/CRP if infection or inflammatory cause suspected |
Why It's Recurring Now
The original injury in January was treated symptomatically (injection + massage + PCM) but without proper core rehabilitation. Sitting for long periods puts continuous load on the lumbar spine and SI joint, which explains why the pain returns specifically in that position. The pain spreading to the spine area suggests either facet joint or disc involvement is now being provoked.
Treatment Approach (General Guidance)
- Short-term: NSAIDs (if no contraindications), continue PCM for pain relief
- Physiotherapy: Core strengthening exercises, lumbar stabilization - this is the most important step that was likely missed in January
- Posture correction: Advise proper sitting posture, avoid prolonged sitting without breaks
- Avoid: Bed rest for extended periods - it worsens recovery
- Injection: If facet joint or SI joint syndrome is confirmed, targeted corticosteroid injection can help
- Refer: If symptoms persist beyond 4-6 weeks despite treatment, or if red flags appear - refer for MRI and specialist review
Bottom line: This patient most likely has a recurrent lumbar musculoskeletal injury (strain + possible facet/SI joint involvement) from the January fall, now triggered by sitting. The most important next steps are a proper physical examination to localize the source, a urine test to exclude renal causes, and starting a structured physiotherapy program for core rehabilitation rather than just symptom management again.
Sources: Bradley and Daroff's Neurology in Clinical Practice; Textbook of Family Medicine 9e
Note: This is clinical guidance only. A proper in-person examination is needed before any diagnosis or treatment decision is finalized.