Evaluation of periprosthetic bone cysts in patients with a Scandinavian total ankle replacement: weight-bearing conventional digital radiographs versus weight-bearing multiplanar reconstructed fluoroscopic imaging.

OBJECTIVE: Periprosthetic bone cysts are a known finding after total ankle replacement (TAR). The significance of cysts is uncertain, but they may threaten the long-term survival of the implant. The aim of this prospective study was to evaluate the diagnostic accuracy of weight-bearing digital radiography compared with 3D weight-bearing multiplanar reconstructed (MPR) fluoroscopic imaging when diagnosing periprosthetic bone cysts in patients who have undergone TAR. SUBJECTS AND METHODS: Forty-two consecutive patients with a Scandinavian Total Ankle Replacement (STAR) were consecutively enrolled and underwent digital radiography and 3D MPR imaging in the same session. All 3D MPR images were interpreted in a blinded fashion, specifically with regard to the presence and extent of periprosthetic bone cysts. Cysts were measured in three planes whenever possible. Interrater and intrarater reliability was assessed by using Cohen kappa test, and comparisons between the two modalities were performed with the Wilcoxon signed-rank and McNemar tests. RESULTS: Significantly more cysts were detected on 3D MPR (74 vs 55) (p = 0.03), with the mean size of cysts detected by 3D MPR significantly larger than that of cysts diagnosed on digital radiography (1545 mm(3) vs 253 mm(3)) (p < 0.0001). Statistical analysis based on the presence or absence of cysts in individual patients did not show a significant difference between 3D MPR and digital radiography (p = 0.23). CONCLUSION: The data imply that cysts are better detected and more accurately measured with 3D fluoroscopic MPR imaging compared with digital radiography, which underestimates not only the presence but also the extent of periprosthetic cysts.

Surgical treatment of midfoot charcot neuroarthropathy review of literature and our results after superconstruct reconstruction of midfoot charcot neuroarthropathy.

BACKGROUND: Charcot neuroarthropathy (CN) of the midfoot was traditionally treated non-operatively with off-loading in a total contact cast (TCC). After introduction of the super construct concept, promising results were reported, however there is a need for further studies on this concept. Analysis of non-operative versus operative treatment is presented as well as our results from a consecutive series of 20 patients operated with the superconstruct concept. METHODS: Twenty patients were operated from July 2017 until June 2020. Mean age was 58 years (50-80), mean weight was 116 kg (68-156), giving a BMI of 31 (26-45). Preoperative patients off-loaded in a TCC until decreased swelling and skin temperature measurement or ulcer had healed, mean 16 weeks immobilization. Surgery was without tourniquet, using a standard medial and lateral incision. Mean follow up is 24 (5-40) months. RESULTS: Mean operation time was 227 (150-315) minutes. Medial column fusion was mandatory, in five cases as an isolated procedure, in 12 cases in combination with lateral column fusion and in three cases with a talocalcaneal fusion. Preoperative lateral Meary angle decreased from 23.5 to 9.6°, antero-posterior Meary angle decreased from 16.0 to 4.7°. Eight patients had postoperative incisional wound problems. Four patients had partial implant removal. All healed with a good clinical result. Two patients had an acute Charcot attack in the ankle joint during postoperative mobilization. One had a severe collapse of the talus resulting in a below knee amputation, giving an amputation rate of 5%. Radiographic examination at follow up, showed bone union of all patients. Nineteen patients are ambulated in orthopedic shoes at latest follow up, giving a 95% satisfactory result. CONCLUSION: Superconstruct reconstruction of CN midfoot collapse is a safe procedure. There are incisional wound problems, recognition and fast treatment of these complications is important to achieve good results. There is a risk for overloading the ankle, initiating a new acute Charcot attack. Attention must be on this problem. The surgical technique is demanding and should be performed by experienced foot and ankle surgeons in a multidisciplinary team set up.

Conservative treatment in a patient with diabetic osteomyelitis: antibiotic treatment is sufficient for complete bone regeneration in selected cases.

Diabetic foot ulcers are commonly complicated by bone involvement and osteomyelitis. Diagnosing diabetic osteomyelitis can be problematic. However, positive findings at clinical examination and X-ray may set the diagnosis. Recent guidelines suggest that selected cases of diabetic osteomyelitis can be treated conservatively with antibiotics. We report on the successful treatment of a 52-year-old man with diabetes with osteomyelitis in the distal phalanx of a toe. On X-ray, the affected phalanx appeared completely eroded. However, regeneration of the bone tissue was observed following outpatient treatment with antibiotics. We therefore encourage doctors to provide conservative treatment for selected cases of diabetic osteomyelitis.