I. Imaging Findings

Based on the provided X-ray and CT images, it can be observed that in the left wrist region involving the distal radius, ulna, and carpal bones, the capitate (located near the center) demonstrates an evident fracture line interrupting the continuity of the cortical bone.
On the coronal and sagittal reconstructed CT images, a transverse or slightly oblique low-density fracture line is visible in the capitate, accompanied by a small fracture gap and disrupted surrounding trabecular pattern.
No definite fracture lines are noted in adjacent carpal bones (e.g., scaphoid, hamate, lunate), but mild bone contusion or small fissure fractures cannot be completely ruled out. Soft tissue swelling is present, with no obvious signs of dislocation.

II. Potential Diagnoses

1. Capitate Bone Fracture: Given the patient’s history of trauma and the imaging findings of a transverse/oblique fracture line, this is highly suggestive. While relatively rare, a capitate fracture can occur under specific external force.
2. Scaphoid Fracture or Other Carpal Bone Fractures: Scaphoid fractures are common in wrist injuries, and other carpal bones may also be involved. If the fracture lines are thin or subtle, further evaluation (e.g., MRI) may be necessary.
3. Carpal Joint Dislocation or Surrounding Ligament Injury: In severe trauma, subluxation or ligamentous damage can occur around the wrist. Current imaging does not indicate a clear dislocation, but it remains in the differential diagnosis.

In summary, based on imaging findings, the most representative diagnosis is “capitate fracture.” Other carpal fractures or wrist ligamentous injuries should be considered as differential diagnoses, and MRI may be used if further investigation is necessary.

III. Final Diagnosis

Considering the 24-year-old patient, who presented with severe left wrist pain following trauma, and the imaging findings that show local fracture signs with a characteristic transverse or oblique fracture line involving the capitate, the most likely final diagnosis is: Left Capitate Fracture (Capitate fracture).

IV. Treatment Plan and Rehabilitation Program

1. Treatment Strategy:

• Conservative Treatment: For capitate fractures without significant displacement or with only mild displacement, a short-arm thumb cast or brace immobilization for 6–8 weeks can be used to stabilize the wrist and thumb, facilitating fracture healing.
• Surgical Treatment: In cases of obvious displacement, instability, or concomitant injuries to other carpal bones, percutaneous pinning (K-wire) or screw fixation, possibly with bone grafting, may be considered to restore joint alignment and prevent avascular necrosis or nonunion.
• Imaging Follow-up: Regular follow-up with X-ray or CT is recommended to assess fracture healing. If avascular necrosis or poor healing is suspected, MRI should be considered.

2. Rehabilitation and Exercise Prescription:

• Immobilization Phase (0 ~ 6-8 weeks):
  • The patient should wear a short-arm thumb spica cast or wrist brace to minimize wrist and thumb movement.
  • Under protective immobilization, perform active range-of-motion exercises of the shoulder, elbow, and fingers (such as making a fist and extending the fingers) to prevent joint stiffness and muscle atrophy.
  • Keep the affected limb elevated to reduce swelling.
• Early Rehabilitation (after cast removal ~ 2nd month):
  • Once the fracture shows signs of healing, under the guidance of a therapist or physician, begin active wrist exercises (flexion, extension, radial and ulnar deviation). Perform each for 5–10 minutes, 2–3 times a day, gradually increasing the range of motion.
  • Light resistance exercises: for example, use a hand gripper with low resistance; proceed with caution based on individual tolerance.
  • Maintain proper posture and allow adequate rest; avoid overuse of the wrist.
• Later Strengthening and Functional Recovery (3rd month ~ 3-4th month):
  • Gradually increase wrist resistance exercises, such as wrist extension and flexion with a resistance band. Start with low intensity and progress to moderate intensity, performing 10–15 minutes each time, 1–2 times a day.
  • Incorporate forearm muscle strength training (e.g., pronation, supination, forearm flexion-extension) to prevent weakness of the forearm muscles.
  • Gradually resume daily activities and sports. If pain or discomfort worsens, stop the activity and seek medical evaluation.

This rehabilitation plan should be individually adjusted, with close attention to pain and swelling at each stage. It is important not to increase training intensity blindly. If the patient has osteoporosis, special functional requirements, or other comorbidities, collaboration with specialists is necessary to formulate a personalized rehabilitation program.

Disclaimer: This report is a reference analysis based on the patient’s current condition and imaging data, and cannot replace an in-person diagnosis or professional medical consultation. If there are any concerns or worsening symptoms, prompt medical attention should be sought.