#264 ‒ Hip, knee, ankle, and foot: common injuries, prevention, and treatment options
Dr. Adam Cohen, a board-certified orthopedic surgeon specializing in sports medicine, discusses the anatomy, common injuries, and treatment options for the hip, knee, ankle, and foot. He also provides advice on finding a good orthopedic surgeon.
Deep Dive Analysis
21 Topic Outline
Anatomy of the Hip and Developmental Dysplasia
Understanding Arthritis and Cartilage Function
Diagnosing Hip Pain in Younger Individuals
Stress Fractures: Types, Diagnosis, and Treatment
Gender Differences and Femoral Acetabular Impingement (FAI)
Advancements in Hip Replacement Surgery
Common Hip Problems in Older Adults: Tendon Issues
Importance of Hip Muscle Strength for Injury Prevention
Hip Fractures in Elderly: Mortality and Management
Orthobiologics: PRP, Bone Marrow, and Fat Injections
Cortisone Injections for Hip Pain
Anatomy and Stability of the Knee Joint
Impact of Activity and Biomechanics on Knee Health
ACL Injuries: Risk Factors and Repair Techniques
Knee Arthritis: Progression and Symptomatic Presentation
Meniscus Tears: Types, Repair, and Conservative Treatment
Total Knee Replacement: Indications and Recovery
Achilles Tendon Issues: Tendinopathy and Rupture
Anatomy and Common Injuries of the Ankle and Foot
Foot Deformities: Bunions and Hammer Toes
Finding a Good Orthopedic Surgeon
9 Key Concepts
Developmental Dysplasia of the Hip (DDH)
A condition where the hip socket (acetabulum) does not form properly in utero or early childhood if the femoral head is not concentrically reduced. This leads to a shallow socket and increased pressure, raising the risk of mechanical overload and arthritis later in life.
Arthritis
A condition characterized by the loss of cartilage, the smooth, frictionless layer at the ends of bones in joints. It's considered a 'whole joint disease' involving inflammation of the synovium and changes in the underlying bone, not just isolated cartilage thinning.
Stress Fracture
A slow-developing bone injury that occurs when repetitive load exceeds the bone's normal healing capacity, leading to tiny microfractures. High-risk stress fractures, such as those on the tension side of the femoral neck, can progress to complete fractures and disrupt blood supply, potentially causing bone death (AVN).
Femoral Acetabular Impingement (FAI)
A condition where an abnormal bony bump (cam lesion) on the femoral neck pinches the acetabular rim and labrum during hip movement. This can cause labral tears and cartilage injury, increasing the risk of developing arthritis.
Orthobiologics (Biologics)
A class of therapies that utilize the body's own natural resources, such as platelets (PRP), bone marrow, or fat, to promote healing of diseased or injured tissue. These are distinct from 'stem cells' as they are minimally manipulated and do not involve injecting pluripotent cells to become new tissue.
Platelet-Rich Plasma (PRP)
A biologic therapy derived from a patient's own blood, which is processed in a centrifuge to concentrate platelets and plasma, rich in growth factors and healing proteins. It is injected into injured tissue to reduce symptoms, with some evidence for effectiveness in conditions like tennis elbow and knee arthritis.
Meniscus
Two semicircular structures (medial and lateral) within the knee joint that help distribute approximately 30% of the load across the knee, protecting the articular cartilage from wear. Tears can either be repaired by sewing them back together or by trimming the torn piece (meniscectomy), depending on the tear type and location.
Patellofemoral Syndrome
Pain around the kneecap (patella) often caused by overloading the patellofemoral joint, commonly seen in activities like running, squatting, and lunging. The pain can originate from the patellar tendon, quadriceps tendon, cartilage, bone, or the fat pad within the knee.
Achilles Tendinopathy
A condition of the Achilles tendon characterized by pain and degeneration, which, contrary to common belief, does not necessarily increase the risk of tendon rupture. Treatment is typically conservative, focusing on strengthening and improving flexibility of the calf muscles.
10 Questions Answered
The hip socket (acetabulum) forms in utero, and if the ball (femoral head) is not concentrically reduced, the socket can become shallow, leading to developmental dysplasia of the hip (DDH) and increasing the risk of arthritis later in life.
In endurance athletes under 50, a primary concern for hip pain is a stress fracture of the femoral neck. These can be high-risk if on the tension side and may require surgery to prevent severe complications like avascular necrosis.
Women tend to have a higher prevalence of conditions like ligamentous laxity and developmental dysplasia, while men are more prone to femoral acetabular impingement (FAI) due to differences in growth plate closure and participation in high-stress sports.
There is currently no FDA-approved 'stem cell therapy' for orthopedic injuries in the United States. What is often marketed as such (e.g., PRP, bone marrow, fat injections) are biologics that use the body's own resources to reduce symptoms, not to grow new pluripotent cells.
No activity, including running, is inherently bad for cartilage; inactivity is worse. Cartilage responds to stress by making more matrix, but excessive activity or poor biomechanics can lead to overload and degeneration.
An ACL injury significantly increases the risk of arthritis later in life, with about 50% of individuals showing signs of arthritis within 15 to 20 years, regardless of whether the ACL was reconstructed or not.
For young individuals without arthritis, a meniscus tear should strongly be considered for repair if possible to preserve joint surface. However, for patients with existing knee arthritis and a degenerative tear, surgery is often no better than conservative treatment.
Recovery from a total knee replacement can take up to a year, with improvements continuing beyond that. Patients are generally advised to avoid contact sports due to the risk of periprosthetic fracture, but many can return to activities like skiing or tennis.
Fluoroquinolones can slightly increase the risk of Achilles tendon rupture, sometimes occurring within a week or two of a single dose. Patients are advised to stop the medication and rest if they experience any pain in the tendon.
A good surgeon listens, makes eye contact, doesn't rush the patient, and is willing to discuss alternatives, complications, and probabilities of outcomes in their own hands, as well as a clear plan for troubleshooting if initial treatments fail.
38 Actionable Insights
1. Strengthen Gluteus Medius/Minimus
Prioritize strengthening the gluteus medius and minimus (hip abductors) from an early age, as these muscles are crucial for preventing numerous lower extremity injuries, including hip fractures and ACL tears, and their strength will naturally degenerate over time.
2. Avoid Inactivity for Cartilage
Engage in appropriate activity to maintain cartilage health, as inactivity is detrimental and significantly depresses the cartilage matrix content.
3. Maintain Good Mechanical Alignment
Strive to maintain good mechanical alignment of the lower extremity, where a plumb line from the hip to the ankle passes through the center of the knee, as misalignment significantly increases the risk of knee degeneration.
4. Lose Weight for Knee Health
Losing even a small amount of weight, such as five pounds, can significantly reduce the load on your knees (e.g., seven times body weight when squatting), potentially delaying or eliminating the need for knee replacement surgery.
5. Engage in Neuromuscular Training
Prioritize neuromuscular training to improve coordination and proprioception, helping to prevent lower extremity injuries by enhancing the body’s ability to react dynamically and recover from unexpected movements.
6. Improve Hip Flexor Flexibility
Actively work on hip flexor flexibility, especially if you sit frequently, as tightness in this muscle group can create imbalances affecting antagonistic muscles like the gluteus maximus and hamstrings.
7. Incorporate Daily Jumping/Plyometrics
Integrate a daily jumping routine, such as jumping rope, into your warm-up to maintain elasticity in the lower body and improve neuromuscular control, which can help prevent injuries.
8. Early Hip Dysplasia Screening
Ensure pediatricians perform thorough hip exams on newborns and consider requesting an ultrasound for better quantification, especially if there are risk factors like breech birth, as early intervention with a brace can prevent future arthritis.
9. Rapid Mobilization Post-Hip Fracture
For elderly patients with hip fractures, immediate surgical intervention and rapid mobilization are critical, as non-operative treatment is a ‘death sentence’ and hospitalization alone can be catastrophic, leading to a 15-30% one-year mortality rate.
10. Optimize Pre-Surgery for Hip Fracture
Implement a team approach, including geriatric specialists, to medically optimize elderly hip fracture patients before surgery, ideally within 48 hours, to ensure they can safely undergo the procedure and improve outcomes.
11. Groin Pain: Stop Running
If an endurance athlete experiences groin pain, immediately stop running and seek medical evaluation to rule out a femoral neck stress fracture, which can have severe consequences if untreated.
12. Surgery for Tension Stress Fracture
Tension-sided femoral neck stress fractures often require surgical pinning to prevent displacement and severe complications like avascular necrosis, leading to a quicker recovery compared to prolonged non-weight-bearing.
13. Rest for Compression Stress Fracture
For compression-sided femoral neck stress fractures, use crutches until pain-free with weight-bearing, then gradually reintroduce exercises and physical therapy over six to eight weeks for healing.
14. Fluoroquinolones: Stop if Pain
If taking fluoroquinolone antibiotics (e.g., Cipro, Levoquin) and experiencing any pain, immediately stop activity and rest, as these medications can increase the risk of Achilles tendon rupture, sometimes even after a single dose.
15. Address Energy Deficiency for Healing
If experiencing recurrent stress fractures or poor healing, investigate potential relative energy deficiency (e.g., female athlete triad), consulting an endocrinologist and checking vitamin D levels, as undernourishment can severely impair bone health.
16. Avoid Contact Sports Post-Replacement
After total hip or knee replacement, avoid contact sports due to the high risk of catastrophic injury (e.g., stress risers above implants), though activities like skiing or tennis may be permissible depending on individual recovery and risk tolerance.
17. Beware ‘Stem Cell Therapy’ Claims
Be highly skeptical of clinics offering ‘stem cell therapy’ for orthopedic issues, as currently, no such therapies are approved by the FDA in the United States for these conditions, and claims of pluripotent cells becoming new cartilage or tendon are not supported.
18. Choose Surgeon Who Listens
When choosing a surgeon, prioritize someone who actively listens, makes eye contact, and does not rush you, as good rapport and communication are crucial for effective care.
19. Inquire Surgeon’s Specific Outcomes
When considering surgery, ask your surgeon for their personal complication rates (e.g., wound infection, reoperation, persistent pain) and their plan for troubleshooting if expected outcomes are not met, as this reflects their competence and ability to manage potential issues.
20. Ask About Surgery Alternatives
Always ask your surgeon about alternatives to surgery and why a surgical approach is recommended over non-operative options; a non-defensive, clear explanation indicates a good surgeon.
21. Plan for Conservative Treatment Failure
Always ensure your doctor outlines a clear plan for what to do if conservative treatments (e.g., physical therapy for an ankle sprain) do not yield improvement within a specified timeframe, as this indicates a thorough approach to your care.
22. Biologics are Symptom Modifying
Understand that current orthopedic biologics (like PRP) primarily act as symptom-modifying treatments, reducing pain rather than regenerating tissue, which can be valuable given the limited effective non-surgical options for conditions like arthritis.
23. PRP for Knee Arthritis
Platelet-rich plasma (PRP) therapy shows promising data as a symptom-modifying treatment for knee arthritis, potentially more effective than cortisone over a year, making it a worthwhile option to explore with a physician.
24. Combine HA and PRP for Knee Arthritis
Consider a combined injection of hyaluronic acid (HA) and platelet-rich plasma (PRP) for knee arthritis, as studies suggest this combination may be more effective at reducing symptoms than either treatment alone.
25. PRP for Tennis Elbow
Platelet-rich plasma (PRP) therapy shows good evidence of efficacy for treating tennis elbow, making it a viable treatment option to discuss with a physician.
26. PRP for Gluteus Medius Tears
Platelet-rich plasma (PRP) therapy appears to work ‘pretty decently’ for gluteus medius tears, offering a potential treatment option.
27. Thorough Diagnosis for Heel Pain
If experiencing heel pain, seek a comprehensive, step-by-step diagnostic approach from a physician, as causes can range from plantar fasciitis and stress fractures to nerve compression or even referred pain from a disc herniation.
28. Prehab Before ACL Reconstruction
Undertake prehabilitation (prehab) before ACL reconstruction surgery to prepare the body, understand long-term implications, and reduce the risk of re-injury, ensuring a smoother recovery process.
29. Quiet Knee Before ACL Surgery
If undergoing ACL reconstruction, consider waiting until the initial inflammation has subsided and the knee is ‘quiet’ (feeling almost normal) before surgery, as this can lead to a better surgical experience.
30. Patellar Tendon Graft for ACL
For young, highly active individuals participating in high-risk sports, the patellar tendon graft is considered the ‘gold standard’ for ACL reconstruction due to its superior strength and lower re-rupture risk, despite a potentially harder early recovery and kneeling pain.
31. Hamstring Graft for Kneeling/Yoga
If you frequently kneel, garden, or practice yoga, discuss using a hamstring tendon graft for ACL reconstruction, as it avoids the kneeling pain associated with patellar tendon grafts, allowing for a more tailored recovery.
32. Allograft for Older, Less Active
If you are over 34 and participate in lower-risk recreational activities (e.g., hiking, not high-level sports), an allograft for ACL reconstruction may be a reasonable option due to easier initial recovery, despite a higher re-rupture risk compared to autografts.
33. Strengthen Quads for Knee Pain
For patellofemoral syndrome (anterior knee pain), engage in quadriceps strengthening exercises, often through physical therapy, to improve kneecap gliding and reduce symptoms.
34. BFR for Quad Strengthening
Consider using blood flow restriction (BFR) training for quadriceps strengthening, especially when higher loads are painful or contraindicated, as it can achieve similar muscle benefits with lower mechanical stress.
35. Conservative Ankle Sprain Treatment
For most ankle sprains, conservative treatment, including strengthening the peroneal muscles, is the initial approach, as the majority of individuals will recover without surgery.
36. MRI for Persistent Ankle Pain
If an ankle sprain is not recovering after conservative treatment, seek an MRI to assess for potential cartilage or bone injury, which may require further intervention.
37. Bunion Surgery for Pain Only
Only consider bunion surgery if the condition causes significant pain or crowds out other toes, as the recovery can be difficult, and it’s not recommended if you are comfortable in your shoes and pain-free.
38. Maintain Calf Flexibility
Ensure good flexibility in both the gastrocnemius and soleus muscles to help prevent Achilles tendon issues and other lower extremity problems.
5 Key Quotes
The coefficient of friction of cartilage is so smooth. It's smoother than ice on ice. There's no man-made substance. I mean, it's smoother than Teflon and it's a biologic substance.
Adam Cohen
If I had any muscle that needed to be worked on and I had to pick one muscle group, it would be that muscle group, starting from early teens. It is implicated in so many lower extremity injuries at the hip and the knee.
Adam Cohen
Nothing's worse for you than inactivity.
Peter Attia
You can't necessarily do everything you wanted to do when you're 20 and 30 because that tendon degeneration is a biologic event that affects all of us.
Adam Cohen
I will always tell them all this is going to take you a year of recovery because I don't know who's going to be shorter than that.
Adam Cohen
3 Protocols
Stress Fracture Treatment (Compression Side of Femoral Neck)
Adam Cohen- Go on crutches until there is no pain with weight bearing.
- Allow six to eight weeks for the fracture to heal.
- Slowly begin exercises to regain endurance and engage in physical therapy.
- Consider a follow-up MRI to confirm healing and ensure the fracture is not worsening.
Stress Fracture Treatment (Tension Side of Femoral Neck)
Adam Cohen- Undergo surgery to insert three pins from the subtrochanteric region into the femoral head.
- Expect quicker healing and often earlier weight bearing compared to compression-sided fractures.
Patient Approach to Finding a Good Orthopedic Surgeon
Adam Cohen, Peter Attia- Observe the surgeon's demeanor: do they sit down, make eye contact, and listen without rushing?
- Ask about alternatives to the proposed treatment (especially surgery) and request a clear explanation of why the recommended approach is preferred now.
- Assess the surgeon's ability to clearly articulate potential complications, their personal probabilities of those complications, and a detailed plan for troubleshooting if the initial treatment or surgery does not yield the desired outcome.