A 76 year old diabetic male patient was referred to the vascular surgeons for a chronic right foot ulcer which was refractory to treatment. An initial x-ray revealed no obvious abnormality. Further imaging was done with MRI which revealed achilles tendon abscess with focal osteomyelitis of the calcaneum.
A 76 year old diabetic male patient was referred by his general practitioner to the vascular surgeons and orthopaedicians for a chronic right foot ulcer which was refractory to treatment. On clinical examination, there was a 3 cm ulcer in the heel of the right foot. There was some sensory loss in the heel of the foot and the pedal pulses were not palpable. X-ray of the right foot did not show any gross abnormality. A MRI was done which showed that the ulceration was directly over the posterior calcaneum. There was a small 1cm area of abnormal signal change noted within the marrow of the calcaneus postero laterally. This was of low signal on T1 images and high signal on T2 and fat suppressed images. Following gadolinium there was enhancement of this region consistent with inflammatory change or focal osteomyelitis. Also the lateral half of the achilles tendon inferiorly at the site of ulceration showed gross destruction. On T1 images there was diffuse intermediate signal replacing much of the tendon with only some normal low signal fibres being seen medially. On T2 images this area was of high signal. There was rim enhancement of the periphery of the achilles tendon following gadolinium. The tendon was expanded and appearances were suggestive of a large abscess in the achilles tendon. Surgical debridement was carried out and appropriate antiniotics were administered which resulted in good clinical improvement.
Most of the pedal infections occur in patients with foot ulcers that result from predisposing conditions such as diabetes, vascular disease or neuropathy. Diabetic patients are predisposed to foot infections because of a compromised vascular supply secondary to diabetes. Local trauma and/or pressure (often in association with lack of sensation because of neuropathy), in addition to microvascular disease, may result in a variety of diabetic foot infections. The spectrum of foot infections in diabetes ranges from simple superficial cellulitis to chronic osteomyelitis. Skin ulceration occurs in areas of highest pressure during ambulation and most frequently involves the plantar aspect of the metatarsophalangeal joints, especially the first and fifth rays, the first toe, and the heel. Tendons in these locations are often situated over a bony prominence where ulceration occurs and are covered only by skin and a thin layer of subcutaneous tissue. As the infection of the soft tissues progresses, bacteria may invade and a long-standing, chronic infection may eventually lead to the destruction of the tendon. In the setting of soft tissue infection, it is extremely important to find out if there is any infection of the adjacent bone and tendons as this will affect the management. Plain x-rays are the most commonly performed initial investigation. However, it cannot pick up the early cases of osteomyelitis and result in considerable delay in diagnosis. Radio-nuclide studies are more sensitive but less specific. Also neither of these studies will be able to reveal the extent of tendinous involvement. In this regard, MRI is most useful for the diagnosis of tendon infection and osteomyelitis. Circular peritendinous contrast enhancement in the setting of a tendon in direct contact with adjacent skin ulceration or cellulitis is highly suggestive of tendon infection. In the case of Achilles tendon, as there is no tendon sheath, purists call it paratendinitis rather than tenosynovitis. Focal isointense or hypointense signal compared with muscle tissue on T1-weighted images with fluid equivalent signal on T2-weighted images and rim enhancement on gadolinium-enhanced T1-weighted images are suggestive of abscess. If there was osteomyeltis, it will be seen as an area of focally decreased marrow signal intensity on T1-weighted images with increased signal intensity on fat-suppressed T2-weighted and fast spin-echo short tau inversion recovery images and with marrow enhancement on gadolinium-enhanced fat-suppressed T1-weighted images. Treatment involves appropriate antibiotics with surgical debridement.
Achilles tendon abscess with focal osteomyelitis of calcaneum
Based on the provided MRI images, the following observations can be made:
In summary, the MRI suggests abscess formation in the right Achilles tendon area and focal osteomyelitis of the calcaneus, consistent with infection-related findings.
Considering the patient’s advanced age, history of diabetes, chronic foot ulcers, MRI findings, and characteristic lesion changes, the most likely diagnoses are:
If further etiological clarification is needed, puncture or surgical exploration with pathological and microbiological culture can be performed to identify the causative organism.
FITT-VP Principle Recommendations: Frequency gradually progresses from 2-3 sessions per week to 3-5 sessions; Intensity starts from very light or light exercise, monitoring foot response; Time increases from 10-15 minutes per session; Type includes walking and resistance band or ankle stability training; Progression is based on healing status and subjective tolerance, with moderate increases every 2-4 weeks.
This report is based on the provided imaging and clinical information, serving as a reference analysis only. It does not replace an in-person consultation or professional medical advice. Should there be any questions or worsening of symptoms, the patient is advised to seek prompt medical attention for further examination and treatment by a qualified specialist.
Achilles tendon abscess with focal osteomyelitis of calcaneum
