Cing Syue Lin

Background: Dieterich disease, or avascular necrosis of the metacarpal head, is a rare condition predominantly affecting adolescents, with fewer than 60 reported cases. We report a rare presentation in a 59-year-old adult with multiple systemic comorbidities. Methods: A 59-year-old man with diabetes, hypertension, and chronic kidney disease presented with progressive right third metacarpophalangeal joint pain without prior trauma. Following radiographic and magnetic resonance imaging (MRI) evaluation, the patient underwent surgical curettage of the necrotic bone followed by autologous iliac cancellous bone grafting. Histopathological examination supported the diagnosis. Results: At the long-term nearly 5-year follow-up, the patient maintained complete symptom resolution, fully restored range of motion, and durable osseous graft integration without secondary collapse or osteonecrotic recurrence. Conclusions: Although most frequently described in adolescents, Dieterich disease should be considered in adults presenting with unexplained metacarpophalangeal joint pain, especially alongside vascular-compromising comorbidities. MRI serves as a valuable adjunct for early lesion detection when radiographs are inconclusive. In this patient, joint-preserving curettage with autologous bone grafting provided durable structural support and favorable long-term functional recovery.

Background/Objectives: Progressive collapsing foot deformity (PCFD) is driven by multiplanar peritalar instability. This study evaluated the clinical and radiographic outcomes of a standardized four-component reconstruction protocol designed to facilitate immediate postoperative weight-bearing in Stage 1a/1b PCFD. Methods: This single-center retrospective study included 20 patients treated between 2015 and 2023 with medializing calcaneal osteotomy, spring ligament repair, flexor digitorum longus (FDL) tendon transfer with internal brace augmentation, and subtalar arthroereisis. Clinical (VAS, AOFAS) and radiographic parameters (anteroposterior and lateral Meary angles, calcaneal pitch, and talonavicular coverage angle) were assessed longitudinally, with subgroup analysis comparing implant removal versus retention. Results: The protocol yielded significant overall improvements. Mean VAS decreased by 4.37 points (p < 0.001), and final AOFAS reached 84.7 ± 7.6 at the final follow-up. Although subtalar arthroereisis was removed in 45% of patients due to symptomatic irritation, subgroup analysis revealed no significant loss of radiographic correction (p > 0.05). Notably, a significant interaction effect was observed for VAS scores (p = 0.002) and AOFAS scores (p = 0.041), with the removal group demonstrating a pronounced functional recovery trajectory following explantation. No major complications occurred. Conclusions: A standardized four-in-one reconstruction provides reliable multiplanar correction in Stage 1a/1b PCFD. The maintenance of structural alignment despite a high implant removal rate supports the role of arthroereisis as a temporary but valuable adjunct for early mobilization. This strategy offers a reproducible framework for joint-preserving PCFD management.

Simple bone cysts (SBC) are benign tumor-like bone lesions typically identified in children. While SBC may lead to growth disturbances or growth arrest, such cases are uncommon. The mechanisms behind these observations remain unclear. Addi tionally, research on the etiology of SBC remains inconclusive, and there has been no consensus on the appropriate timing and methodology for treatment. Here, we present our experience in the successful surgical management of a 10-year-old girl with SBC, who presented with a pathological fracture complicated by malunion of the displaced fracture, varus deformity, and limb length discre pancy. We hypothesized two possible etiologies for the patient’s growth arrest and subsequent humerus varus deformity: (1) Direct disruption of the physis by fluid from the cyst itself; and (2) damage to the epiphysis due to repetitive pa thological fractures associated with SBC. In addressing this case, surgical in tervention was undertaken to correct the proximal humerus varus deformity. This approach offered the advantages of simultaneously correcting angular abnor malities, achieving mild limb lengthening, providing definitive SBC treatment, and reducing the overall treatment duration. As per current literature, acute correction of acute angular deformity in proximal humeral SBC is not well comprehended. However, in this specific case, acute correction was considered an optimal solution.