| CASE OF THE MONTH - March 2005 |
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History:
A 16 year-old female basketball player presented with chronic left foot pain of two months duration. She could not recall a specific mechanism of injury or traumatic episode. Her past history was significant for Achilles tendonitis and previous ankle sprains. This pain was located over the mid/lateral aspect of the left foot both during activity and rest. She described the pain as a “dull ache” with occasional “shooting” pains. She also noted occasional tingling of the lateral foot but denied numbness and weakness of the lower extremity. Her menstrual and diet history were unremarkable. |
Physical Exam:
Inspection revealed normal gait without soft tissue swelling or ecchymosis. The patient demonstrated bilateral pes planus foot deformities. Active and passive ROM was full and equal bilaterally. Tenderness was noted over the fourth and fifth metatarsal head and shafts along with the cuboid bone. Peroneal and tibialis posterior strength was full with mild pain upon resisted eversion. There was no pain with single toe raises. Distal neurovascular findings were within normal limits. Anterior drawer, talar tilt, squeeze test, and Thompson test were within normal limits. Pain was not reproduced with tapping over the tarsal tunnel. Gross sensation, pulses, and reflexes were within normal limits. |
Initial Differential Diagnosis based on the History and Physical:
1. Metatarsalgia
2. Stress fracture
3. Peroneal tendonitis
4. Entrapment neuropathy |
Diagnostic studies:
Plain Radiographs of the foot: AP, lateral, and oblique views of the foot. Bone Scan |
Final Diagnosis:
Plain Radiographs: AP, lateral, and oblique films of the foot were within normal limits.
Bone Scan: Revealed marked uptake in the region of the cuboid bone.
Cuboid Stress Fracture |
Treatment and Outcome:
The patient was made non-weight bearing with crutches and protected in a fracture walker and followed clinically until pain free.
The patient was allowed to swim and ride a stationary bicycle to maintain cardiovascular fitness if tolerated and pain free.
Orthotics were prescribed upon return to activity.
Gradual return to full activity took place over a three month period of time.
The patient did well and returned to competitive basketball without complication. |
Discussion:
“Stressfractures of the cuboid bone are a rare injury with only a few case reports in the literature.
The underlying pathogenesis is the same as for all stressfractures. A repetitive load is applied to the bone. When this load exceeds the bone's threshold of elastic deformation, a stressfracture occurs. The exact mechanism that produces a cuboidstressfracture has not been determined. Based on the cause of cuboid fracture, it can be speculated that a repetitive abduction of the forefoot on the hindfoot causes the stressfracture as the cuboid bone is compressed between the calcaneus and the bases of the fourth and fifth metatarsals. Bone that is deficient or a foot that is misshapen also could predispose an individual to develop a stressfracture.
Diagnosing a cuboidstressfracture requires a high index of suspicion. Patients report pain over the lateral aspect of the foot. There often is a history of recent increased activity, such as a runner who has markedly increased his or her training regimen. Physical examination reveals tenderness over the cuboid bone, often suggesting a diagnosis of peroneal tendinitis.The diagnosis usually is made with a bone scan that characteristically shows marked uptake in the cuboid bone. Radiographs often are nondiagnostic because changes occur late and are subtle. MR imaging also identifies the stressfracture and is helpful particularly if more unusual diagnoses, such as bone tumors or localized osteomyelitis, need to be ruled out.
Treating cuboidstressfractures involves an initial period of relative immobilization and activity modification followed by a gradual return to full activities. Patients with moderately severe symptoms can be treated in a below-knee cast for 4 to 6 weeks. For patients with mild symptoms, weight bearing with activity modification to avoid impact loading the area for 4 to 6 weeks may be all that is required to heal the fracture. After the symptoms have resolved completely, the patient begins a graduated program leading to a resumption of full activities.” |
Referencess:
From: Pinney SJ. Fractures of the tarsal bones. Orthop Clin North Am. 2001;32(1):21-33. |
Case provided by:
KYLE J. CASSAS, M.D., is assistant professor of family medicine at the University of Texas Southwestern Medical Center. |