ObjectiveTo discuss the feasibility and accuracy of distal femoral patient-specific cutting guide in total knee arthroplasty (TKA) based on knee CT and full-length X-ray film of lower extremities. MethodsBetween July 2016 and February 2017, 20 patients with severe knee joint osteoarthritis planned to undergo primary TKA were selected as the research object. There were 9 males and 11 females; aged 53-84 years, with an average of 69.4 years. The body mass index was 22.1-31.0 kg/m2, with an average of 24.8 kg/m2. The preoperative range of motion (ROM) of the knee joint was (103.0±19.4)°, the pain visual analogue scale (VAS) score was 5.4±1.3, and the American Hospital of Special Surgery (HSS) score was 58.1±11.3. Before operation, a three-dimensional model of the knee joint was constructed based on the full-length X-ray film of lower extremities and CT of the knee joint. The distal femoral patient-specific cutting guide was designed and fabricated, and the thickness of the distal femoral osteotomy was determined by digital simulation. The thickness of the internal and external condyle of the distal femur osteotomy before operation and the actual thickness of the intraoperative osteotomy were compared. The intraoperative blood loss, postoperative drainage loss, and hidden blood loss were recorded. The ROM of knee joint, VAS score, and HSS score at 3 months after operation were recorded to evaluate effectiveness. The position of the coronal and sagittal plane of the distal femoral prosthesis were assessed by comparing the femoral mechanical-anatomical angle (FMAA), anatomical lateral distal femoral angle (aLDFA), mechanical femoral tibial angle (mFTA), distal femoral flexion angle (DFFA), femoral prosthesis flexion angle (FPFA), anatomical lateral femoral component angle (aLFC), and the angle of the femoral component and femoral shaft (α angle) between pre- and post-operation.ResultsTKA was successfully completed with the aid of the distal femoral patient-specific cutting guide. There was no significant difference between the thickness of the internal and lateral condyle of the distal femur osteotomy before operation and the actual thickness of the intraoperative osteotomy (P>0.05). All patients were followed up 3 months. All incisions healed by first intention, and there was no complications such as periarticular infection and deep vein thrombosis. Except for 1 patient who was not treated with tranexamic acid, the intraoperative blood loss of the rest 19 patients ranged from 30 to 150 mL, with an average of 73.2 mL; the postoperative drainage loss ranged from 20 to 500 mL, with an average of 154.5 mL; and the hidden blood loss ranged from 169.2 to 1 400.0 mL, with an average of 643.8 mL. At 3 months after operation, the ROM of the knee was (111.5±11.5)°, and there was no significant difference when compared with the preoperative one (t=–1.962, P=0.065). The VAS score was 2.4±0.9 and HSS score was 88.2±7.5, showing significant differences when compared with the preoperative ones (t=7.248, P=0.000; t=–11.442, P=0.000). Compared with the preoperative measurements, there was a significant difference in mFTA (P<0.05), and there was no significant difference in aLDFA, FMAA, or DFFA; compared with the preoperative plan, there was no significant difference in FPFA, aLFC, or α angle (P>0.05). ConclusionThe use of distal femoral patient-specific cutting guide based on knee CT and full-length X-ray film of lower extremity can achieve precise osteotomy, improve coronal and sagittal limb alignment, reduce intraoperative blood loss, and obtain satisfactory short-term effectiveness.
Objective To compare the accuracy and effectiveness of orthopaedic robot-assisted minimally invasive surgery versus open surgery for limb osteoid osteoma. Methods A clinical data of 36 patients with limb osteoid osteomas admitted between June 2016 and June 2023 was retrospectively analyzed. Among them, 16 patients underwent orthopaedic robot-assisted minimally invasive surgery (robot-assisted surgery group), and 20 patients underwent tumor resection after lotcated by C-arm X-ray fluoroscopy (open surgery group). There was no significant difference between the two groups in the gender, age, lesion site, tumor nidus diameter, and preoperative pain visual analogue scale (VAS) scores (P>0.05). The operation time, lesion resection time, intraoperative blood loss, intraoperative fluoroscopy frequency, lesion resection accuracy, and postoperative analgesic use frequency were recorded and compared between the two groups. The VAS scores for pain severity were compared preoperatively and at 3 days and 3 months postoperatively.Results Compared with the open surgery group, the robot-assisted surgery group had a longer operation time, less intraoperative blood loss, less fluoroscopy frequency, less postoperative analgesic use frequency, and higher lesion resection accuracy (P<0.05). There was no significant difference in lesion resection time (P>0.05). All patients were followed up after surgery, with a follow-up period of 3-24 months (median, 12 months) in the two groups. No postoperative complication such as wound infection or fracture occurred in either group during follow-up. No tumor recurrence was observed during follow-up. The VAS scores significantly improved in both groups at 3 days and 3 months after surgery when compared with preoperative value (P<0.05). The VAS score at 3 days after surgery was significantly lower in robot-assisted surgery group than that in open surgery group (P<0.05). However, there was no significant difference in VAS scores at 3 months between the two groups (P>0.05). Conclusion Compared with open surgery, robot-assisted resection of limb osteoid osteomas has longer operation time, but the accuracy of lesion resection improve, intraoperative blood loss reduce, and early postoperative pain is lighter. It has the advantages of precision and minimally invasive surgery.