ObjectiveTo evaluate the early effectiveness of the robot-assisted total hip arthroplasty (THA) via direct superior approach (DSA).MethodsBetween March 2021 and April 2021, 11 patients (11 hips) were treated with a robot-assisted THA via DSA. There were 7 males and 4 females, with an average age of 55 years (range, 26-73 years). There were 5 patients of osteoarthritis secondary to hip dysplasia and 6 patients of osteonecrosis of femoral head. Preoperative hip Harris score was 55.8±6.3. The operation time, volume of blood loss, length of incision, postoperative blood transfusion and hospital stay, and the incidence of surgical complications were recorded. The visual analogue scale (VAS) score and Harris score were used to evaluate hip joint pain and function. The leg length discrepancy (LLD) was measured on the X-ray films. The inclination angle and anteversion angle of the acetabular component were also measured, and the difference between the planned and actual values were compared.ResultsOne THA was performed via conventional posterolateral approach finally because of poor exposure. The rest of 10 THAs were performed with assistance of robotic arm via DSA. The average operation time was 89 minutes (range, 65-120 minutes); the average length of incision was 10.5 cm (range, 9-13 cm); and the average blood loss was 400 mL (range, 110-740 mL). One patient was given a blood transfusion for 2 unit. All incisions healed by first intention and no neurovascular injury, deep vein thrombosis, or fracture occurred. The length of hospital stay after operation was 2-6 days (mean, 4.4 days). The duration of follow-up was 1-3 months (mean, 2.1 months). The VAS score was 0 in 9 patients and 2 in 1 patient at the day of discharge. At last follow-up, the hip Harris score was 84.9±6.7, showing significant difference when compared with that before operation (t=−8.717, P=0.000). The inclination and anteversion angles were (37.4±2.0)° and (17.1±4.5)°, respectively, and there was no significant difference when compared with the planned values [(38.2±1.6)°, (16.6±3.7)°] (t=1.809, P=0.104; t=–1.103, P=0.299). The LLD ranged from –2 to 4 mm. No complication such as dislocation, aseptic loosening, or periprosthetic joint infection occurred. ConclusionThe robot-assisted THA via DSA has encouraged early effectiveness.
ObjectiveTo explore the mid-term effectiveness of total hip arthroplasty (THA) with subtrochanteric shortening osteotomy in treatment of Crowe type Ⅳ developmental dysplasia of the hip (DDH).MethodsBetween September 2009 and March 2014, a total of 49 patients (57 hips) who were diagnosed with Crowe type Ⅳ DDH were treated with THA and subtrochanteric shortening osteotomy. Of the 49 patients, 7 were male and 42 were female with an average age of 44.6 years (range, 20-73 years). The preoperative Harris score was 44.68±3.39 and the preoperative leg length discrepancy was (5.27±0.55) cm.ResultsAll incisions healed primarily. All patients were followed up 32-87 months (mean, 52.1 months). At last follow-up, the Harris score was 85.67±2.89 and the leg length discrepancy was (1.12±0.48) cm, showing significant differences when compared with the preoperative values (t=–69.53, P=0.00; t=42.94, P=0.00). X-ray films showed that bone union of the femoral osteotomy end at 6 months after operation. There was no loosening and subsidence of prosthesis at last follow-up.ConclusionThe subtrochanteric shortening osteotomy with THA in treatment of Crowe type Ⅳ DDH can obtain satisfactory mid-term effectiveness with low risk of peripheral vascular and nerve traction injuries.
Objective To analyze the impact of robot assistance on the restoration of limb length and offset distance in total hip arthroplasty (THA). Methods A retrospective analysis was conducted on the clinical data of 316 patients who underwent unilateral primary THA between September 2019 and August 2023. Among them, 117 patients underwent robot-assisted THA (group A), and 199 patients underwent conventional THA (group B). There was no significant difference between the two groups in the gender, age, or side of the hip replacement (P>0.05); but there was a significant difference in the preoperative diagnosis (P<0.05). The leg length discrepancy (LLD) and global offset (GO) dfference were measured on preoperative anteroposterior pelvic X-ray films, and absolute values were used for comparison between groups. Results The operations in both groups were successfully completed. Postoperative imaging measurements showed that the LLD and GO dfference in group A were significantly lower than those in group B (P<0.05). Among them, group A had 32 cases (27.4%), 5 cases (4.3%), and 0 case (0) of LLD>3 mm, >5 mm, and >10 mm, respectively, while group B had 115 cases (57.8%), 75 cases (37.7%), and 22 cases (11.1%), respectively; and the differences in above indicators between groups were significant (P<0.05). Group A had 40 cases (34.2%), 3 cases (2.6%), and 0 case (0) of GO dfference>5 mm, >10 mm, and >20 mm, respectively; group B had 103 cases (51.8%), 54 cases (27.1%), and 7 cases (3.5%), respectively. There was no significant difference in the proportion of patients with GO>20 mm between groups (P>0.05), while there were significant differences in other indicators between groups (P<0.05). Conclusion Compared with traditional THA, robot assisted THA has more advantages in restoration of limb length and offset distance.
ObjectiveTo explore the clinical outcomes of acetabular revision using a metal reconstruction cage. MethodsBetween October 2006 and October 2013, 16 patients (16 hips) underwent acetabular revision with a metal reconstruction cage. There were 4 males and 12 females, with the mean age of 62.7 years (range, 49-78 years). The time from total hip arthroplasty to revision was 3-15 years (mean, 8.2 years). The causes for revision were aseptic acetabular loosening in 15 cases, and femoral periprosthetic fracture (Vancouver type B3) in 1 case. According to the American Academy of Orthopaedic Surgeons (AAOS) classification, there were 12 cases of type III and 4 cases of type IV; according to the Paprosky classification, there were 12 cases of type IIIA and 4 cases of type IIIB. Harris score was used for hip function evaluation, and visual analogue scale (VAS) for pain in the thigh. X-ray films were taken for imaging evaluation. ResultsHealing of incision by first intention was obtained in all patients. Deep venous thrombosis occurred in 1 patient, and was cured after anticoagulation therapy. No complications of infection, neurovascular injury, and prosthetic dislocation were found. Sixteen patients were followed up 6.8 years on average (range, 2-9 years). The Harris score was significantly increased from preoperative 42.44±4.66 to 91.88±3.28 at last follow-up (t=–106.30, P=0.00). Two patients had mild pain in the thigh, but pain disappeared at 1 year after operation. At immediate after operation, the abduction angle was 37-54° (mean, 42.9°). The distance between acetabular rotation centre and teardrop line was (33.67±12.19) mm for preoperative value and was (20.67±9.63) mm for postoperative value, showing significant difference (t=–9.60, P=0.00). The distance between acetabular rotation centre and lateral teardrop was (34.98±12.30) mm for preoperative value and was (40.04±6.61) mm for postoperative value, showing significant difference (t=–3.15, P=0.00). X-ray film results showed bony fusion at the osteotomy sites at 4 to 12 months after operation. No continuous radiolucent line, prosthetic dislocation, or osteolysis was found, and bony ingrowth was observed in all patients. No patient received re-revision due to prosthetic loosening. ConclusionThe metal reconstruction cage for acetabular revision can achieve good effectiveness for patients with serious bone defect.
Objective To evaluate the effect of preoperative digital planning in acetabular reconstruction of total hip arthroplasty (THA) for development dysplasia of the hip (DDH). Methods A prospective study was performed on 42 patients with DDH undergoing primary THA between January 2009 and December 2011. The patients were divided into 2 groups according to whether preoperative digital planning was made or not; before operation, conventional imaging method was used in 23 cases (group A), and TraumaCad software was used for preoperative digital planning in 19 cases (group B). There was no significant difference in gender, age, body mass index, DDH classification, and preoperative Harris score between 2 groups (P gt; 0.05). The operation time, amount of bleeding, and postoperative complication were observed. After 7 days of operation, X-ray films were done to measure the vertical location, horizontal location, radiographic anteversion angle, radiographic inclination angle, and prosthesis size by TraumaCad software. The qualified rate of cup placement was compared between 2 groups. Coincidence rate of cup size between preoperative predicted by the digital planning and actually implanted in group B also was calculated. Results The operation time and the amount of bleeding were (119.25 ± 47.16) minutes and (410.00 ± 200.39) mL in group A and were (155.31 ± 84.03) minutes and (387.50 ± 251.99) mL in group B respectively, showing no significant difference between 2 groups (P gt; 0.05). Incision infection and prosthetic anterior dislocation occurred in 1 case of group A respectively, prosthetic posterior dislocation in 1 case of group B. The patients were followed up 1 year and 1 month to 4 years and 1 month (mean, 2 years and 8 months ) in group A, and 1 year and 3 months to 4 years (mean, 2 years and 7 months) in group B. At last follow-up, the Harris scores were 91.09 ± 5.35 in group A and 91.72 ± 3.48 in group B, which were significantly increased when compared with preoperative scores (P lt; 0.05), but no significant difference was found between 2 groups (t=0.41, P=0.69). The qualified rate of cup placement of group B (78.95%, 15/19) was significantly higher than that of group A (43.48%, 10/23) (χ2=5.43, P=0.02); the coincidence rate of the cup size between preoperative predicted by the digital planning and actually implanted was 68.42% (13/19). ConclusionPreoperative digital planning can further optimize the acetabular reconstruction in THA for DDH.
Objective To explore the treatment of dislocation after total hip replacement. Methods From July 1997 to October 2004, 23 casesof dislocation after total hip replacement were treated,including 9 males and 14 females and aging 5379 years. The CT and serial X-ray films were taken to observe the position of prostheses. The strength of their hip abductor was also tested. In the patients without loosening, closed reduction was attempted at first. The stability of hip was tested. If closed reduction failed, the offset or/and parts of the components was adjusted, then the capsular was repaired. If instabilitystill existed, revision was adopted. Results In 23 cases of dislocation, 10 cases were treated successfully by closed reduction. In 12 patients who failed reduction, 5 were given open reduction combined with capsular repairing; the offset was adjusted by lengthening femoral head in 2 cases; rim liners were elevated in 2 cases; and larger offset was used and abnormal liner was adjusted in 1 case. Revision was used in 1 case having loosening and 2 cases having instability. Allpatients were followed up 1 year to 5 years (1.9 years on average). The Harrisscoring was 7294 (87 on average). Conclusion The treatment of dislocation after total hip replacement should use different ways according to the causes of dislocation and the stability of hip.
ObjectiveTo investigate the accuracy and value of digital planning with bone parameters in determining the appropriate prosthesis for total hip arthroplasty (THA). MethodsThe preoperative radiographs was taken in 13 cases scheduled for THA between September 2012 and June 2013; the bone parameters were measured by digital template, and the prosthesis was selected and preoperative plan was made. There were 4 males and 9 females with an average age of 54.08 years (range, 41-79 years), including 8 left hips and 5 right hips. The causes were osteonecrosis of the femoral head in 8 cases and femoral neck fracture in 5 cases (3 cases had osteonecrosis of the femoral head). ResultsThe operation time was 140-254 minutes (mean, 191.8 minutes). Two cases received blood transfusion, and 6 patients received plasma substitutes transfusion. There was no intraoperative fractures or postoperative thrombosis; atherosclerotic plaque occurred in 2 cases. Thirteen cases were followed up 12-24 months with an average of 17.3 months. The pain was relieved and limb function was improved in all patients. Harris score was significantly improved from preoperative 54.0±12.9 to 91.1±4.1 at 3 months after operation (t=7.259, P=0.000). Compared with the actual implants, the appropriate sizes of femoral stem was selected in 12 cases (92.31%) (excellent in 9 cases, good in 3 cases, and poor in 1 case), and the appropriate sizes of acetabular cup was selected in 11 cases (84.62%) (excellent in 7 cases, good in 4 cases, and poor in 2 cases). ConclusionDigital planning could increase the accuracy in choosing the size of prosthesis for THA.
ObjectiveTo evaluate the effectiveness of total hip arthroplasty (THA) combined with subtrochanteric osteotomy in the treatment of Crowe type Ⅳdevelopmental dysplasia of the hip (DDH).MethodsBetween April 2008 and June 2016, 71 patients with unilateral Crowe type Ⅳ DDH were treated with THA. Of 71 cases, 44 were performed with subtrochanteric osteotomy (osteotomy group) and 27 were performed without subtrochanteric osteotomy (non-osteotomy group). There was no significant difference in gender, age, body mass, height, body mass index, affected side, and preoperative Harris score between 2 groups (P>0.05). The complications were recorded and the effectiveness was assessed by Harris score. Besides, the femoral dislocation height and the settling depth of sleeve were measured in the pelvic anteroposterior X-ray film pre- and post-operatively.ResultsOsteotomy group was followed up 12-90 months (mean. 34.77 months), and non-osteotomy group was followed up 12-79 months (mean, 34.33 months). There was no significant difference in follow-up time between 2 groups (t=–0.088, P=0.930). There was 11 cases of intraoperative or postoperative complications in osteotomy group, and 3 cases of postoperative complications in non-osteotomy group. Among the osteotomy group, 1 case had nonunion due to infection and received revision after 20 months. No loosening or dislocation of the implant occurred in both 2 groups. Significant differences were found in femoral dislocation height and settling depth of sleeve between 2 groups (t=–8.452, P=0.000; t=6.783, P=0.000). Moreover, the osteotomy length was not correlated with the settling depth of sleeve (r=–0.038, P=0.806). At last follow-up, there was no significant difference in Harris score between 2 groups (t=–1.160, P=0.254).ConclusionTHA combined with subtrochanteric osteotomy can provide a favorable outcome for treating Crowe type Ⅳ DDH. Furthermore, patients with higher femoral dislocation and severely narrow femoral proximal canals are prone to be peformed with subtrochanteric osteotomy.