Joint-preserving prosthetic reconstruction for massive bone defects has the potential to be a new and revolutionary treatment option. In this paper, we discuss the case of a 30-year-old female patient who presented with pain and swelling around the knee for three months. The patient underwent this procedure. Postoperative patient satisfaction, pain scores, and range of motion results were found to be promising. We believe that this method has the potential to be the next stage in the quest for better treatment options for this condition.

The present study aims to investigate the effect of amount of lateralization and/or anteversion of the point where the iliac cut meets with the posterior column cut of periacetabular osteotomy (PAO), on X-ray parameters such as Center of edge (CE) angle, retroversion index (RVI) and sharp angle. Fourteen patients with symptomatic hip dysplasia (CE° < 20°) were included. Pelvis Computerized tomography (CT) sections were used for 3D printing. PAO was then performed on these models. The point (A), 1 cm lateral to the pelvic brim, is marked where the iliac cut intersects the posterior column cut. In Group I (1.5–0), point A is lateralized parallel to the osteotomy line for 1.5 cm. In Group II (1.5–0.5), it is additionally anteverted for 0.5 cm. In Group III (3–0), point A is lateralized for 3 cm and then additionally anteverted for 1 cm (Group IV: 3–1). Radiographs were taken in each stage. The lateral CE angle, RVI and sharp angle were measured. All had an increase in the CE angle and RVI and a decrease in the sharp angle compared to the control group (P < 0.05). The amount of CE angle (ΔCE) or RVI increase (ΔRV) was as follows: 3–1(38°, 0.3) > 3–0(27°, 0.2) and 1.5–0.5(25°, 0.1) > 1.5–0(17°, 0.07) (P < 0.05) (with no difference between groups 1.5–0.5 and 3–0, P = 0.7). The amount of sharp angle decrease was as follows: 3–1(20°), 3–0(18°) < 1.5–0.5(11°) < 1.5–0(8°) (P < 0.05). The lateralization of the intersection point where the iliac wing cut meets with the posterior column cut along the cut surface led to an increase of lateral cover and focal retroversion. Additional anteversion leads to further increases in those parameters, while groups 1.5–0.5 and 3–0 did not differ between.

Background Rotating hinged knee prosthesis is frequently used for certain indications. The indications and results for rotating hinge knee prosthesis in primary and revision arthroplasty are controversial. The aim of this study was to investigate the effects on hip function following rotating hinged knee arthroplasty surgery and to compare outcome of primer and revision rotating hinged knee arthroplasty.Methods 46 patients underwent rotating hinged knee prosthesis by a single surgeon; including 21 primary arthroplasty and 38 revision, 59 knees arthroplasty were included. Hospital for Special Surgery (HSS) knee scores, SF-12 quality of life scale, joint range of motion, VAS score, Harris hip scores (HHS) were evaluated before and after surgery.Results A statistically significant increase was found in both hip joint HHS scores in patients with rotating hinged knee replacement. A statistically significant improvement was found in HSS scores, knee joint VAS in patients with rotating hinged knee replacement (p < 0.05). Hip osteoarthritis stage did not progress statistically compared to preoperative values following rotating hinged knee arthroplasty. The hip functions of ipsilateral and contralateral sides improved in terms of limping, assistive device, walking distance, and wearing socks and shoes. A moderate positive correlation was found between knee scores and hip scores.Conclusion A successful knee arthroplasty surgery in patients with advanced biomechanical problems contributes to the improvement in hip function by improving the biomechanics and functions of the knee joint. It is necessary to evaluate all joints and bone structures in both lower extremities to make better preoperative planning.