Cartilage injuries in the knee, particularly in the medial compartment, are common causes of persistent knee pain and functional limitation in active individuals. When conservative management fails, and especially in younger patients who are not yet candidates for joint replacement, combining biologic therapy with realignment surgery can offer excellent outcomes. In this blog post, we discuss how Bone Marrow Aspirate Concentrate (BMAC) and Opening Wedge High Tibial Osteotomy (HTO) work together to treat medial compartment cartilage damage — illustrated with a real patient case.
Understanding the Problem: Medial Compartment Cartilage Injury
The medial compartment of the knee bears a significant portion of the body’s weight. When cartilage in this area becomes damaged, it has very limited capacity for natural healing. Over time, even mild malalignment can lead to focal cartilage degeneration, pain, swelling, and eventually, arthritis.
Patient Case Study: Joint Preservation in a 41-Year-Old Female
Patient: 41-year-old active female
Complaint: Right knee medial joint pain for over 6 months
Findings:
- X-rays: Mild narrowing of the medial tibiofemoral joint space
- MRI: Grade 3–4 cartilage wear on the weight-bearing portion of the medial femoral condyle
MRI showing Grade 3–4 cartilage loss over the weight-bearing portion of the medial femoral condyle
- Mechanical axis: Passing through the medial tibial spine, indicating varus malalignment
Preoperative long leg standing X-ray showing mechanical axis passing through the medial tibial spine, with mild medial joint space narrowing.
Despite physical therapy and medication, her symptoms persisted and affected her ability to stay active. Given her young age and localized cartilage damage, we recommended a joint-preserving approach combining:
- Opening wedge high tibial osteotomy (HTO) to correct alignment
- Bone marrow aspirate concentrate (BMAC) to biologically enhance cartilage repair
Step 1: Realigning the Knee – High Tibial Osteotomy
In her case, the mechanical axis was contributing to overloading of the medial compartment. We performed an opening wedge HTO to shift the load-bearing axis more laterally.
This involved:
- Making a surgical cut in the upper tibia
- Opening a wedge on the inner (medial) side
- Filling the wedge with graft material
- Fixing the bone in its new alignment using a plate
This procedure:
- Unloaded the damaged medial compartment
- Reduced pressure on the cartilage lesion
- Slowed further degeneration
Before and After HTO
Step 2: Biologic Enhancement – Bone Marrow Aspirate Concentrate
During surgery, we also harvested bone marrow from her pelvis. The aspirate was processed into a concentrated solution rich in stem cells and growth factors (BMAC).
This was applied directly to the medial femoral condyle lesion, enhancing the biologic environment for cartilage healing. BMAC is known to:
- Stimulate regeneration of cartilage-like tissue
- Reduce local inflammation
- Support long-term joint health
Cartilage wear in the medial femoral condyle.
The cartilage lesion is debrided down to bone and to a stable rim.
Bone marrow aspiration concentrate (BMAC is injected to fill the defect.
Recovery and Outcome
Postoperatively, she followed a structured rehabilitation protocol, including:
- Partial weight-bearing with crutches for 6–8 weeks
- Progressive physiotherapy
- Return to light activity by 3–4 months
At her 6-month review:
- She reported significant pain reduction
- X-rays showed stable alignment correction
- She resumed low-impact exercise with minimal discomfort
Why Combine HTO and BMAC?
This dual approach targets both the mechanical and biological causes of cartilage damage.
| High Tibial Osteotomy (HTO) | Bone Marrow Aspirate Concentrate (BMAC) |
| Offloads the medial compartment | Stimulates cartilage repair |
| Corrects misalignment | Reduces inflammation |
| Delays arthritis progression | Promotes tissue regeneration |
Together, they offer a comprehensive joint-preserving solution — ideal for active patients not yet ready for joint replacement.
Conclusion
For younger patients with focal cartilage damage and malalignment, combining High Tibial Osteotomy with Bone Marrow Aspirate Concentrate can effectively relieve pain, improve function, and preserve the natural joint.
If you are experiencing persistent knee pain and want to explore personalized treatment options, speak with an orthopaedic specialist trained in biologics and alignment correction.
