1. Imaging Findings

Based on the provided right foot X-ray and CT images, soft tissue swelling is observed in the tarsal region of the right foot. On the initial X-ray, no significant fracture line is seen. However, the CT clearly demonstrates a fracture line at the medial cuneiform of the right foot. This fracture shows minimal displacement, primarily indicated by an interruption of the local cortical continuity and altered trabecular structure. No obvious avulsion signs are found in the surrounding soft tissue, suggesting an isolated (not involving other tarsometatarsal or cuneiform groups) fracture of the medial cuneiform.

2. Potential Diagnoses

1. Isolated Medial Cuneiform Fracture: This diagnosis best fits the current imaging and clinical Presentation. Medial cuneiform fractures can result from traffic accidents or direct trauma, and the fracture line may be subtle and easily missed on routine X-ray.
2. Stress Fracture: In cases of repeated stress or overuse on the foot, a stress fracture could occur. However, such fractures are commonly associated with a history of prolonged or excessive exercise. Given the history of a motor vehicle accident in this case, a stress fracture is less likely.
3. Bipartite (Congenital) Medial Cuneiform: This is a congenital variation in which the cuneiform may appear as two separate ossification centers. Typically, it presents with a regular outline, without an obvious fracture line or periosteal reaction, and with minimal clinical symptoms.
4. Lisfranc Injury: If the tarsometatarsal joint or the bases of the metatarsals and cuneiforms were involved, more extensive ligament and joint displacements would be seen, characteristic of a Lisfranc injury. In this case, the CT does not demonstrate obvious joint diastasis or displacement of the metatarsal bases.

3. Final Diagnosis

Considering the patient's history of injury from a motor vehicle accident, persistent dorsal foot pain, and the CT findings, the most likely diagnosis is “Isolated Medial Cuneiform Fracture” (without significant displacement). This conclusion aligns with the clinical symptoms and is consistent with common misdiagnosis features.

4. Treatment Plan and Rehabilitation Program

For an isolated medial cuneiform fracture (with no significant displacement), conservative treatment is typically employed, combined with gradual rehabilitation:

1. Conservative Treatment:
   • Non-weight-bearing for the first 2–4 weeks (using crutches or a brace) to reduce movement at the fracture site and facilitate healing.
   • If no obvious external fixation is required, an arch support or protective soft brace can be used to lessen localized stress.
   • Pain control may include appropriate use of analgesics, anti-edema medications, or local cold compresses, depending on symptom severity.
2. Rehabilitation Training (FITT-VP Principle):
   • F (Frequency): During the early fracture phase (2–4 weeks), perform light foot exercises once or twice a day; increase to 2–3 times per day based on recovery progress in the later phase.
   • I (Intensity): Start with active ankle range-of-motion exercises without weight-bearing. Progress gradually to partial weight-bearing when pain subsides, followed by gentle heel lifts and light walking exercises.
   • T (Time): Initially, each session can last 1–2 minutes. As pain tolerance improves, gradually extend each session to 3–5 minutes or appropriately longer.
   • T (Type): Focus on active dorsiflexion and plantarflexion of the ankle and foot, light toe gripping, and exercises strengthening the foot arch muscles. Later, progress to walking, low-intensity cycling, or swimming as non-impact aerobic options.
   • V (Volume): Gradually increase the total time of foot activity as rehabilitation progresses, closely monitoring swelling and pain.
   • P (Progression): When fracture healing shows clear signs of callus formation and pain has significantly improved (around 6–8 weeks), consider resuming light jogging or higher-intensity lower extremity functional exercises.
3. Follow-Up and Assessment:
   • Imaging follow-up every 4–6 weeks is recommended to evaluate fracture healing.
   • If persistent pain or newly developed deformity and joint instability appear, promptly revisit for assessment of fracture displacement or other complications.

Disclaimer: This report is for reference and analysis purposes only, and cannot replace an in-person consultation or professional medical advice. For a specific diagnosis and treatment plan, please integrate the patient’s actual condition and consult a specialist.