ObjectiveTo investigate the clinical characteristic differences of cementless total hip arthroplasty (THA) between with and without subtrochanteric femoral shortening osteostomy in Crowe type IV developmental dysplasia of the hip (DDH). MethodsBetween January 2006 and March 2012, 21 patients (21 hips) with Crowe type IV DDH who underwent primary THA were enrolled according to inclusion criteria. According to whether subtrochanteric femoral shortening osteostomy was performed during THA or not, the patients were divided into 2 groups: THA with osteostomy group (n=9) and THA without osteotomy group (n=12). There was no significant difference in gender, age, body mass index, and hip Harris score between 2 groups (P>0.05) except leg length discrepancy (t=-3.170, P=0.005). The operation time, blood loss, postoperative drainage, complications, and radiography data were compared to evaluate the clinical characteristics. ResultsThe operation time, blood loss, and postoperative drainage of osteotomy group were all significantly greater than those of no osteotomy group (P<0.05). All patients achieved primary healing of incision; 1 patient (1 hip) had transient sciatic nerve symptom in osteotomy group. The average follow-up time was 53 months (range, 28-88 months). The X-ray films showed good fracture healing at 3-6 months after operation in osteostomy group. No prosthetic loosening or dislocation was found. The hip Harris score was 90.67±4.06 in osteostomy group and 92.17±3.27 in no osteostomy group, showing no significant difference between 2 groups (t=-0.938, P=0.360). The leg length discrepancy was (0.22±0.26) cm in osteostomy group and (0.18±0.27) cm in no osteostomy group, showing no significant difference (t=107.000, P=0.546). The leg length discrepancy was found in 6 patients of osteotomy group and 5 patients of no osteotomy group. One patient complained of thigh pain in osteotomy group; 2 patients had slight limp (Trendelenburg +) in no osteotomy group. ConclusionTHA can improve joint function and increase limb length in the treatment of Crowe type IV DDH. Subtrochanteric shortening osteotomy is an effective treatment which can be performed according to preoperative template measurement, leg length shortening, and the soft tissue tension.
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 study the effectiveness and acetabular prosthesis selection of the total hip arthroplasty (THA) for Crowe type IV congenital dysplasia of the hip with dislocation in adults. Methods Between June 2008 and May 2012, 8 adult patients (8 hips) with Crowe type IV congenital dysplasia of the hip with dislocation underwent THA. They were all female, aged 20-35 years with a mean age of 25 years. The left hip was involved in 5 cases and the right hip in 3 cases. The Harris score of involved hip was 53.9 ± 6.6. The shortened length of involved extremity was 4-6 cm (mean, 4.8 cm). The X-ray films showed complete dislocation in all cases. The acetabular prosthesis with diameter of 42-44 mm and S-ROM femoral prosthesis were used in THA. Results The incisions healed by first intention. There was no hip dislocation events and sciatic nerve injury during the follow-up. Femoral nerve injury occurred in 1 case and asymptomatic venous thrombosis of the leg muscle occurred in 2 cases. All the patients were followed up 1-5 years (mean, 3 years). All cases showed obvious improvement of claudication and could restore to work. At 6 months after operation, the mean length difference between affected and contralateral extremities was 0.4 cm (range, — 1.0-0.6 cm); the Harris score was significantly increased to 87.6 ± 0.3 (t=1.77, P=0.00). The X-ray films showed that all cases got bony union at 3-6 months after operation and stable interface between acetabular prosthesis and bone. No revision was involved during the follow-up. Conclusion THA with small acetabular cup and subtrochanteric osteotomy is an effective method in the treatment of Crowe type IV congenital dysplasia of the hip with dislocation in adults. The early effectiveness is satisfactory. The long-term survival rate of prosthesis needs to be followed up.
Objective To explore the expressions of bone morphogenetic protein 2 (BMP-2) and runt-related transcription facotr 2 (Runx2) and microarchitecture of trabecular bone periacetabula in adult patients with developmental dysplasia of the hip (DDH). Methods Between March and September 2008, the trabecular bone periacetabulum was collected from 8 patients with DDH who were scheduled for total hip arthroplasty (aged 37-55 years, 3 males and 5 females, trial group) and from 8 patients with avascular necrosis of the femoral head (Ficat stage II) who were scheduled for hip resurfacing arthroplasty (aged 36-55 years, 3 males and 5 females, control group). The expressions of BMP-2 and Runx2 in the trabecular bone were determined by real-time quantitative PCR, and the microarchitecture was observed by micro-CT and the following parameters were determined: bone volume/total volume (BV/TV), connectivity density (Conn.Dens), trabecular number (Tb. N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), and structure model index (SMI). Results The expressions of BMP-2 and Runx2 were significantly lower in trial group than in control group (P lt; 0.05). The micro-CT showed sparse trabecular bone in trial group and dense trabecular bone in control group. BV/TV and Tb.N in trial group were significantly lower than those in control group, and SMI and Tb.Sp in trial group were significantly higher than those in control group (P lt; 0.05); there was no significant difference in Conn.Dens and Tb.Th between 2 groups (P gt; 0.05). Conclusion The trabecular bone is in a low metabolism condition and its microarchitecture is tendency to be osteoporosis trabecualr bone in adult patients with DDH. It may be related with the acetabular component loosening after total hip arthroplasty.
Objective To investigate the effectiveness of absorbable pins for reconstructing pelvic stability in Salter innominate osteotomy for treating development dysplasia of the hip (DDH). Methods Between January 2003 and December 2008, 392 patients (440 hips) with DDH underwent a Salter procedure. There were 68 boys (82 hips) and 324 girls (358 hips) with a mean age of 3 years and 3 months (range, 1 year and 6 months-5 years). According to Tonnis classification criteria, 13 hips were rated as grade I, 304 hips as grade II, 82 hips as grade III, and 41 hips as grade IV. Based on the degree of displacement of the femoral head and acetabular index on the anteroposterior pelvic X-ray film, operation method was selected before operation. A total of 341 hips were managed with open reduction and Salter innominate osteotomy, and 99 hips with Salter innominate osteotomy and femoral shortening rotating osteotomy. All cases underwent autologous iliac crest grafting and fixation between osteotomy sites and bone graft with 2 absorbable pins. Results At 1 day after operation, anteroposterior pelvic X-ray examination showed concentric reduction in all hips, having no instability of the joint of the osteotomy sites or bone graft shifting. A total of 368 patients (413 hips) were followed up 1 to 7 years (mean, 3 years and 10 months). At 3 months after operation, no bone graft in stability or shift, and sliding or loosening of pins occurred. At last follow-up, concentric reduction rate was 100%; after hip loading, 358 patients had no claudication and limited hip activities, who had the stability of hips and negative Allis and Ortalani signs. No abnormal height growth was observed in all patients. According to Mckay’s hip function evaluation criteria, the results were excellent in 390 hips, good in 16 hips, and fair in 7 hips, with an excellent and good rate of 98.3%; according to Severin X-ray criteria, the results were excellent in 386 hips, good in 17 hips, and fair in 10 hips, with an excellent and good rate of 97.6%. Conclusion Absorbable pins can replace steel pins for fixation of the osteotomy sites and bone graft in Salter innoninate because of flexible and convenient operation without a need for reoperation of steel pins extraction.
Objective To investigate the effectiveness of subtrochanteric shortening with overlapping femoral resection in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip (DDH). Methods Between January 2004 and December 2010, 37 patients (44 hips) with Crowe type IV DDH underwent subtrochanteric shortening with overlapping femoral resection in total hip arthroplasty with cementless prosthesis. There were 15 males (18 hips) and 22 females (26 hips) with an average age of 42 years (range, 24-46 years). Unilateral hip was involved in 30 cases and bilateral hips in 7 cases. Preoperative X-ray films showed complete dislocation of the femoral head and hypoplasia of the acetabulum and proximal femur. Before operation, the leg discrepancy was (5.5 ± 1.1) cm, and the Harris score was 32.1 ± 5.2. Results The mean operation time was 4.3 hours (range, 3-6 hours); the mean blood loss was 760 mL (range, 600-1 000 mL). All patients obtained primary healing of incision. The patients were followed up 1-8 years (mean, 6.7 years). Pain relief was achieved; 6 cases had mild claudication; 3 cases had femoral nerve palsy; and no stretch injury of sciatic nerve was observed. X-ray films showed that acetabular cups were in normal position. The healing time of fracture was 3-6 months (mean, 3.7 months). The leg discrepancy was (1.5 ± 1.0) cm at 1 day after operation, showing significant difference when compared with preoperative one (t=16.45, P=0.00). The Harris score was 94.3 ± 3.8 at 3 months after operation, showing significant difference when compared with preoperative score (t=59.15, P=0.00). No revision of acetabular and femoral prostheses was performed during follow-up. Conclusion Subtrochanteric shortening with overlapping femoral resection in total hip arthroplasty is a safe method of restoring the anatomic hip center in Crowe type IV DDH in adults. It can avoid reduction difficulty caused by soft tissue contracture and injuries of sciatic nerve and femoral nerve caused by limb lengthening.
Objective To compare the biomechanical effects between rotational acetabular osteotomy and Chiari osteotomy for developmental dysplasia of the hip (DDH) by biomechanical test. Methods Sixteen DDH models of 8 human cadaver specimens were prepared by resecting the upper edge and posterior edge of acetabulum. And the Wiberg central-edge angle (CE) of the DDH model was less than 20°. Then the rotational acetabular osteotomy was performed on the left hip and Chiari osteotomy on the right hip. When 600 N loading was loaded at 5 mm/minute by a material testing machine, the strain values of normal specimens, DDH specimens, and 2 models after osteotomies were measured. Results In normal specimens, the strain values of the left and right hips were 845.63 ± 533.91 and 955.94 ± 837.42 respectively, while the strain values were 1 439.03 ± 625.23 and 1 558.75 ± 1 009.46 respectively in DDH specimens, which was about 2 times that of normal hips. The morphology and X-ray examinations indicated that the DDH model was successfully established. The strain value was 574.94 ± 430.88 after rotational acetabular osteotomy, and was significantly lower than that of DDH specimens (t=4.176, P=0.004); the strain value was 1 614.81 ± 932.67 after Chiari osteotomy, showing no significant difference when compared with that of DDH specimens (t=0.208, P=0.841). The strain value relieved by rotational acetabular osteotomy was significantly higher than that by Chiari osteotomy (t= — 2.548, P=0.023). Conclusion Rotational acetabular osteotomy is better than Chiari osteotomy in relieving hip joint stress of DDH.
ObjectiveTo explore the surgical technique and the effectiveness of reconstructing the hip center in total hip arthroplasty (THA) for developmental dysplasia of hip (DDH). MethodsBetween January 2004 and January 2010, 29 patients (32 hips) with DDH underwent THA. There were 6 males (6 hips) and 23 females (26 hips), aged 45-67 years (mean, 50.6 years). The locations were left side in 22 hips and right side in 10 hips. According to Crowe classification, 12 hips were rated as Crowe I and 20 hips as Crowe II. The patients had limb length discrepancy of 1.9-4.4 cm. The Harris score was 50.7 ± 8.6. ResultsAll incisions healed by first intension. Posterior hip dislocation occurred in 1 case (1 hip) after operation. All patients were followed up 2 years-4 years and 6 months (mean, 2.3 years). The lower limbs were lengthened by 0.5-5.8 cm (mean, 2.5 cm). The Harris score was 87.7 ± 5.9 at 1 year after operation, showing significant difference when compared with preoperative score (t=21.77, P=0.00). X-ray films showed loosening of acetabular component in 1 case (1 hip) and displacement of acetabular component with too large abduction angle in 1 case (1 hip); no loosening and subsidence of acetabular or femoral components occurred in the other patients during follow-up. The horizontal location of hip center, the vertical distance between teardrop and the hip center, the vertical acetabular abduction angle, and the femoral offset were better than those before operation (P lt; 0.05). ConclusionFor DDH patients, reconstructing the hip center in THA can lengthen the limb, improve the joint function, and reduce the failure rate of joint replacement.
ObjectiveTo summarize the design and the biomechanical characteristics of Sivash-range of motion femoral modular stem (S-ROM) prosthesis and mainly to introduce its clinical use in developmental dysplasia of hip (DDH) and hip revision. MethodsLiterature concerning S-ROM prosthesis was extensively reviewed and analyzed. ResultsThe S-ROM prosthesis based on the modularity feature can reach press-fit in metaphysis and diaphysis of femur concurrently. Additionaly, S-ROM prosthesis can fit for anatomic differences of the DDH femur and is capable of use in correction osteotomy and hip revision. ConclusionModular junctions of S-ROM prosthesis increase the potentials of implant fracture and metallic debris production, so further follow-up study is needed to verify the long-term effectiveness.
Objective To evaluate the efficacy of total hip arthroplasty (THA) combined with femoral head autograft for Crowe type II and type III developmental dysplasia of the hip (DDH). Methods From January 2001 to January 2004, THA was performed for 23 patients (29 hips) with osteoarthritis secondary to DDH. There were 20 females (26 hips) and 3 males (3 hips) with an average age of 52 years (range 43-65 years). Unilateral DDH occurred in 17 patients and bilateral DDH occurred in6 patients. Based on radiographic classification of Crowe, there were 17 cases (20 hips) of type II and 6 cases (9 hips) of type III. The length difference was (2.9 ± 0.8) cm between two lower l imbs of the unilateral DDH patients. The Harris scores were 43.6 ± 13.8 preoperatively. The standard procedure of THA was performed in 3 patients (4 hips), the structural femoral head autograft for restoring normal level of rotating center of the acetabulum in other patients. Results The incision healed by first intention in all patients. No patient suffered compl ications after operation. The duration of follow-up ranged from 4 to 7 years (average 5.6 years). The X-ray films showed bony heal ing between the grafted bone and the il ium in all patients. At last follow-up, the length difference was (0.9 ± 0.2) cm between two lower l imbs and the Harris score was 86.3 ± 6.4; showing statistically differences (P lt; 0.05) when compared with preoperation. The X-ray films showed no dislocation of acetabulum, and femoral prosthesis, and no signs of dislocation, absorption and collapse of the grafted bone. Conclusion THA combined with structural femoral head autograft for patients with osteoarthritis secondary to DDH can obtain favorable results. This method can restore normal level of rotating center of the acetabulum, provide rel iable acetabular fixation, and restore acetabular bone stock in patients with Crowe type II and type III DDH.