Patient MRI of the right hip shows a medial femoral neck stress reaction/incomplete stress fracture, low‑grade strain of the right vastus lateralis and adductor magnus, a small anterior superior labral tear, mild right hip effusion, and gluteus medius insertional tendinosis. What is the diagnosis and recommended management?

Medial Femoral Neck Stress Reaction/Incomplete Stress Fracture with Associated Hip Pathology

This patient has a low-risk medial "compression-type" femoral neck stress reaction/incomplete stress fracture that should be treated conservatively with strict non-weight-bearing for 2-4 weeks followed by gradual return to activity, with the other findings (labral tear, muscle strains, tendinosis) managed expectantly as they are secondary and do not alter the primary treatment plan. 1

Primary Diagnosis: Medial Femoral Neck Stress Injury

The MRI findings of mild-to-moderate osseous and periosteal edema with focal cortical thickening along the medial femoral neck represent a stress reaction progressing toward an incomplete stress fracture. 1 This is critical to distinguish from lateral femoral neck stress fractures:

• Medial "compression-type" stress fractures are low-risk and can be managed conservatively with protected weight-bearing 1
• Lateral "tension-type" stress fractures are high-risk, inherently unstable, prone to displacement, and often require prophylactic percutaneous screw fixation 1, 2
• The medial location in this case is favorable and does not require surgical intervention unless it progresses 1

Management Algorithm for Medial Femoral Neck Stress Fracture

Initial Treatment Phase (Weeks 0-2)

• Strict non-weight-bearing with crutches or walker 1, 2
• This prevents progression to complete fracture, which carries devastating consequences including nonunion, displacement, and avascular necrosis 1, 2
• The patient must understand that femoral neck stress fractures are classified as high-risk anatomic locations where delayed diagnosis or inadequate treatment can lead to fracture completion 1, 3

Follow-up Imaging (Weeks 2-3)

• Obtain follow-up radiographs at 10-14 days to assess for progression 1
• Follow-up radiographs have increased sensitivity (30-70%) compared to initial radiographs (15-35%) due to development of overt bone reaction 1
• If symptoms persist or worsen, repeat MRI without contrast to evaluate for fracture line progression or complications such as osteonecrosis 1, 2

Gradual Return to Activity (Weeks 4-12)

• Once pain-free with activities of daily living, begin progressive weight-bearing 2
• MRI signal abnormalities typically resolve within 3-6 months in 90% of patients 4
• Do not rely on complete resolution of MRI edema to clear for activity—clinical pain-free status is the primary determinant 1, 4
• Athletes may require repeat MRI to predict return-to-play timing, as MRI grading correlates with recovery duration 1

Secondary Findings: Clinical Significance

Low-Grade Muscle Strains (Vastus Lateralis, Adductor Magnus)

• The mild intramuscular edema represents low-grade strains that are secondary findings 1
• These will heal with the same non-weight-bearing protocol required for the stress fracture 1
• No additional specific treatment is needed beyond the primary management plan 1

Small Anterior Superior Labral Tear

• This fluid-filled oblique tear is an incidental finding that does not change acute management 1
• Labral tears are common and often asymptomatic 5
• Address only if hip pain persists after the stress fracture has healed and rehabilitation is complete 1

Gluteus Medius Insertional Tendinosis

• Mild tendinosis is a common finding that can mimic stress fracture symptoms 5
• This is likely contributing to lateral hip pain but is not the primary pathology 5
• Tendinopathy will improve with rest during the non-weight-bearing period 5

Mild Hip Joint Effusion

• Small effusions are nonspecific and commonly seen with stress reactions 1
• This does not indicate infection or other acute pathology requiring intervention 1

Critical Pitfalls to Avoid

Do not allow weight-bearing too early—medial femoral neck stress fractures can progress to complete fractures if inadequately treated, leading to displacement, nonunion, and avascular necrosis 1, 2, 6

Do not dismiss persistent symptoms after 6 months—if abnormal MRI signal intensity persists beyond 6 months, this likely represents new injury rather than the original stress fracture 4

Do not confuse this with a lateral femoral neck stress fracture—lateral fractures require immediate orthopedic consultation for prophylactic surgical fixation 1, 2

Do not pursue surgical treatment of the labral tear acutely—the stress fracture is the primary pathology and must heal first 1

Do not rely on radiographs alone for follow-up—if clinical symptoms persist despite negative or unchanged radiographs, obtain MRI to evaluate for complications 1, 2