Objective To evaluate the effectiveness of distal femoral osteotomy aided by three-dimensional (3D) printing cutting block for correction of vaglus knee with osteoarthritis. Methods Between January 2014 and January 2016, 12 patients (15 knees) with vaglus deformity and lateral osteoarhritis underwent medial closing wedge distal femoral osteotomy. There were 5 males and 7 females, aged 30-60 years (mean, 43.8 years). The mean disease duration was 6.6 years (range, 1–12 years). The unilateral knee was involved in 9 cases and bilateral knees in 3 cases. According to Koshino’s staging system, 1 knee was classified as stage I, 9 knees as stage II, and 5 knees as stage III. The X-ray films of bilateral lower extremities showed that the femorotibial angle (FTA) and anatomical lateral distal femoral angle (aLDFA) were (160.40±2.69)° and (64.20±2.11)° respectively. Mimics software was used to design and print the cutting block by 3D printing technique. During operation, the best location of distal femoral osteotomy was determined according to the cutting block. After osteotomy, internal fixation was performed using a steel plate and screws. Results All incisions healed primarily; no complication of infection or deep vein thrombosis was observed. All patients were followed up 6-18 month (mean, 12.2 months). At 6 months after operation, the hospital for special surgery (HSS) score for knee was significantly improved to 89.07±2.49 when compared with preoperative score (65.27±1.49,t=–28.31,P=0.00); the results were excellent in 10 knees, good in 4 knees, and fair in 1 knee with an excellent and good rate of 93.3%. The bony union time was 2.9-4.8 months (mean, 3.3 months). Bone delayed union occurred in 1 case (1 knee). The postoperative FTA and aLDFA were (174.00±1.41)° and (81.87±1.06)° respectively, showing significant differences when compared with preoperative ones (t=–18.26，P=0.00;t=–25.19,P=0.00). The percentage of medial tibial plateau in whole tibial plateau was 49.78%±0.59%, showing no significant difference when compared with intraoperative measurement (49.82%±0.77%,t=0.14,P=0.89). Conclusion 3D printing cutting block can greatly improve the accuracy of distal femoral osteotomy, and ensure better effectiveness for correction of vaglus knee with osteoarthritis.
ObjectiveTo investigate the short-term effectiveness of derotational distal femoral osteotomy (DDFO) combined with medial patellofemoral ligament (MPFL) reconstruction in treatment of recurrent patellar dislocation with excessive femoral anteversion angle (FAA≥30°). MethodsBetween June 2017 and August 2019, 17 patients with recurrent patellar dislocation with FAA≥30° were treated with DDFO and MPFL reconstruction. There were 5 males and 12 females, aged 14-22 years, with an average of 17.7 years. The patella dislocated for 2 to 8 times (mean, 3.6 times). The disease duration was 2-7 years (mean, 4.6 years). The patellar apprehension tests were positive. Preoperative pain visual analogue scale (VAS) score, Lysholm score, Tegner score, and Kujala score were 4.2±1.1, 47.8±8.1, 3.6±1.1, and 56.8±5.7, respectively. FAA, mechanical lateral distal femoral angle (mLDFA), lateral patella displacement (LPD), tibial tuberosity-trochlear groove distance (TT-TG) were (34.9±3.4)°, (85.8±3.0)°, (13.7±3.8) mm, and (23.1±2.1) mm, respectively. ResultsAll incisions healed by first intention, and there was no complications such as knee stiffness, infection, and re-dislocation of the patella. All patients were followed up 13-25 months, with an average of 17.7 months. The imaging review showed that 1 case of osteotomy did not union, and achieved satisfactory results after the secondary revision and strengthening fixation; the osteotomies of other patients healed completely after 3 to 4 months of operation. The patellar apprehension tests were negative. At last follow-up, the FAA, mLDFA, LPD, and TT-TG were (15.6±2.7)°, (83.0±2.1)°, (5.0±2.6) mm, and (20.5±2.5) mm, respectively; the VAS score, Lysholm score, Tegner score, and Kujala score were 2.4±1.4, 93.4±7.8, 6.8±1.5, and 89.0±8.0, respectively. There were significant differences in the above indicators between pre- and post-operation (P<0.05). ConclusionDDFO combined with MPFL reconstruction for the recurrent patellar dislocation with excessive FAA (≥30°) can achieve good short-term effectiveness, significantly reduce knee pain, and improve function.