Objective To investigate the effectiveness of Salter osteotomy combined with subtrochanteric shortening and derotational osteotomy in treating Tönnis type Ⅲ and Ⅳ developmental dysplasia of the hip (DDH) in children and explore the urgical timing. Methods A retrospective collection was performed for 74 children with Tönnis type Ⅲ and Ⅳ DDH who were admitted between January 2018 and January 2020 and met the selection criteria, all of whom were treated with Salter osteotomy combined with subtrochanteric shortening and derotational osteotomy. Among them, there were 38 cases in the toddler group (age, 18-36 months) and 36 cases in the preschool group (age, 36-72 months). There was a significant difference in age between the two groups (P<0.05), and there was no significant difference in gender, side, Tönnis typing, and preoperative acetabular index (AI) (P>0.05). During follow-up, hip function was assessed according to the Mckay grade criteria; X-ray films were taken to observe the healing of osteotomy, measure the AI, evaluate the hip imaging morphology according to Severin classification, and assess the occurrence of osteonecrosis of the femoral head (ONFH) according to Kalamchi-MacEwen (K&M) classification criteria. Results All operations of both groups were successfully completed, and the incisions healed by first intention. All children were followed up 14-53 months, with an average of 27.9 months. There was no significant difference in the follow-up time between the two groups (P>0.05). At last follow-up, the excellent and good rates according to the Mckay grading were 94.73% (36/38) in the toddler group and 83.33% (30/36) in the preschool group, and the difference between the two groups was significant (P<0.05). The imaging reexamination showed that all osteotomies healed with no significant difference in the healing time between the two groups (P>0.05). There was no significant difference in AI between the two groups at each time point after operation (P>0.05), and the AI in the two groups showed a significant decreasing trend with time extension (P<0.05). The result of Severin classification in the toddler group was better than that in the preschool group at last follow-up (P<0.05). There was no significant difference in the incidence of ONFH between the two groups (P>0.05). In the toddler group, 2 cases were K&M type Ⅰ; in the preschool group, 3 were type Ⅰ, and 1 type Ⅱ. There was no dislocation after operation.ConclusionSalter osteotomy combined with subtrochanteric shortening and derotational osteotomy is an effective way to treat Tönnis type Ⅲ and Ⅳ DDH in children, and surgical interventions for children aged 18-36 months can achieve better results.
ObjectiveTo investigate the anatomical morphology of the proximal femur in adult patients with Crowe type IV developmental dysplasia of the hip (DDH) so as to provided a reference for the selection of femoral components or personalized artificial prosthesis for DDH. MethodsBetween June 2004 and December 2014, 49 patients (58 hips) with Crowe type IV DDH were included in this study. There were 7 males (8 hips) with an average age of 47.3 years and 42 females (50 hips) with an average age of 30.0 years. X-ray films were taken in all cases and CT scanning in 17 cases (17 hips). The anatomical parameters were measured through Osirix V 5.8.5 software. ResultsThe distance of femoral head dislocation was (6.09±1.04) cm;the femoral head and neck disappeared completely in 8 hips (13.8%);femoral head atrophy and deformation and femoral neck disappearance were observed in 11 hips (19.0%). The midpoint width of the small trochanteric canal was (1.53±0.29) cm;the isthmus diameter was (0.69±0.09) cm;the canal flare index (CFI) value was (3.50±0.42) cm;the femoral neck anteversion angle was (37.0±18.2)°;and all indexes showed significant difference when compared with ones of normal population and Crowe type I, II, and III patients. But there was no significant difference in femoral neck-shaft angle (132.3±9.1°), isthmus height (11.66±2.67) cm (P<0.05). The chimney type cavity (CFI<3) accounted for 51.7%, which was significantly higher than the value of normal population. There was a positive correlation between metaphyseal CFI and CFI (r=0.63, P=0.00), but there was no correlation between metaphyseal CFI and distal CFI (r=-0.17, P=0.21). ConclusionThe proximal femur has the morphological characteristics of narrow medullary cavity, increased anteversion angle, and high ratio of chimney type cavity, so it is necessary to design specialized femoral components or personalized artificial prosthesis for the DDH.
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 evaluate early to medium-term effectiveness of total hip arthroplasty (THA) in patients with a history of hip preservation surgery with secondary severe osteoarthritis for developmental dysplasia of the hip (DDH). Methods The clinical data of 25 DDH patients (31 hips) who had severe osteoarthritis after hip preservation surgery and received THA between September 2009 and March 2021 were retrospectively analyzed. There were 1 male and 24 females; the age ranged from 18 to 65 years, with an average age of 43 years; 8 hips were classified into Crowe type Ⅰ, 9 hips were type Ⅱ, 3 hips were type Ⅲ, and 11 hips were type Ⅳ. The time between osteotomy and THA ranged from 31 to 51 years, with an average of 31.96 years. Preoperative hip flexion range of motion was (69.31±29.72)°, abduction range of motion was (24.00±14.79)°; and Harris hip score was 45.3±15.5. Postoperative Harris hip score, hip range of motion, complications, radiographic findings, and implant survival rate were analyzed. Results Patients in both groups were followed up 2-132 months, with an average of 51 months. During the follow-up, periprosthetic fracture occurred in 1 case; there was no complication such as dislocation, periprosthetic infection, nerve palsy, or deep vein thrombosis. At last follow-up, the hip flexion range of motion was (109.52±11.17)°, abduction range of motion was (41.25±5.59)°, showing significant differences when compared with preoperative values (t=8.260, P=0.000; t=6.524, P=0.000). The Harris hip score was 91.5±4.1, and the difference was significant when compared with preoperative score (t=11.696, P=0.000); among them, 13 cases were excellent and 12 cases were good. Radiographic evaluation showed that the center of acetabular rotation moved up 0-18 mm (mean, 6.35 mm). The cup abductor angle was 28°-49° (mean, 37.74°) and the coverage rate was 69.44%-98.33% (mean, 81.04%). All femoral stems were fixed in neutral position without varus or valgus. No osteolysis, radiolucent line, or implant migration was observed. By the end of follow-up, none of the patients underwent revision and the survival rate of prothesis was 100%. ConclusionTHA is still the gold standard for the treatment of DDH patients with secondary osteoarthritis after hip preservation surgery. The postoperative joint function can be rapidly restored, the patients’ quality of life can significantly improve, and the early to medium-term survival rate of the prosthesis is satisfactory.
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.
Objective To investigate the morphological changes of the proximalfemur and their implication to the total hip arthroplasty in patients with Crowe Ⅱ/Ⅲ developmental dysplasia of the hip (DDH). Methods The experimental gr oup was composed of 15 hips in 14 patients (Crowe Ⅱ, 9 hips; Crowe Ⅲ, 6 hips ) with osteoarthritis secondary to Crowe Ⅱ/Ⅲ DDH (2 males, 12 females; age, 35-61 years). None of the patients had accepted any osteotomy treatment. The control group was composed of 15 normal hips in 15 patients with unilateral DDH (3 males, 12 females; age, 35-57 years). Twelve hips came from the experimental group and the other 3 came from the patients with unilateral Crowe Ⅰ DDH. The femurswere examined with the CT scanning. The following parameters were measured: theheight of the center of the femoral head (HCFH), the isthmus position (IP), theneckshaft angle(NS), the anteversion angle, the canal flare index, and the canal width. Then, the analysis of the data was conducted. Results HCFH and IP in theexperimental group and the control group were 50.1±6.7 mm, 50.1±7.4 mm, and 107.4±21.5 mm, 108.7±18.1 mm，respectively, which had no significant differencebetween the two groups（Pgt;0.05）. In the experimental group and the control group, the NS were 138.3±10.0° and 126.7±5.7°，the anteversion angles were 36.5±15.9° and 18.8±5.4°, and the canal flare indexes were 4.47±0.40and 5.01±0.43. There was a significant difference between the two groups in the above 3 parameters （Plt;0.05）. As for the canal width of the femur, therewasa significant difference in the interior/exterior widths and the anterior/posterior widths at the level of 2 cm above the lesser trochanter and 4 cm belowthe lesser trochanter between the two groups （Plt;0.05）; however, there was nosignificant difference in the canal width of the femur at the isthmus between the two groups（P＞0.05）. Conclusion It is necessary to evaluate the morphology of the proximal femur before the total hip arthroplasty performed in patients with Crowe Ⅱ/Ⅲ DDH. The straight and smaller femoral prosthesis should be chosen and implanted in the proper anteversion position duringoperation.
Objective To investigate the changes of low back pain (LBP) and spinal sagittal parameters in patients with unilateral Crowe type Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). Methods The clinical data of 30 patients who met the selection criteria between October 2018 and March 2020 were retrospectively analyzed. Patients were divided into LBP group (16 cases) and control group (14 cases) according to whether there was LBP before operation. There was no significant difference between the two groups of patients in gender, age, body mass index, affected sides, preoperative Harris score (P>0.05). Full-length lateral X-ray films of the spine were taken within 1 week before operation and at 1 year after operation, and the following imaging indicators were measured: sacral slope (SS), lumbar lordosis (LL ), spinal tilt (ST), spine-sacral angle (SSA), sagittal vertebral axis (SVA). The visual analogue scale (VAS) score, lumbar Oswestry disability index (ODI), the Harris score of the hip joint before operation and at 1 year after operation, and the occurrence of postoperative complications were collected and analysed. Results In the LBP group, LBP was relieved to varying degrees at 1 year after operation, of which 13 patients (81.3%) had complete LBP remission; VAS score decreased from 4.9±2.3 preoperatively to 0.3±0.8, ODI decreased from 33.5±22.6 preoperatively to 1.3±2.9, the differences were all significant (t=7.372, P=0.000; t=5.499, P=0.000). There was no new chronic LBP in the control group during follow-up. The Harris scores of the two groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between the two groups at 1 year after operation (t=0.421, P=0.677). There was no significant difference in imaging indexes between the two groups before operation and the difference between pre- and post-operation (P>0.05). At 1 year after operation, ST and SVA in the LBP group, SSA in the control group, and SS in the two groups significantly improved when compared with those before operation (P<0.05); there was no significant difference in the other indexes between the two groups before and after operation (P>0.05). Conclusion Unilateral Crowe type Ⅳ DDH patients with LBP before operation were all relieved of LBP after THA. The relief of LBP may be related to the improvement of spinal balance, but not to lumbar lordosis and its changes.
Objective To investigate the long-term effectiveness of primary total hip arthroplasty (THA) in treatment of Crowe type Ⅳ developmental dysplasia of the hip (DDH). Methods A clinical data of Crowe type Ⅳ DDH patients treated with primary THA between January 2002 and August 2008 and followed up more than 13 years was retrospectively analyzed. Forty-two patients (45 hips) met the selection criteria and were enrolled in this study. There were 13 males and 29 females with an average age of 43.5 years (range, 18-65 years). There were 39 patients of unilateral hip and 3 of bilateral hips. The preoperative Harris score was 38.3±10.7 and leg length discrepancy of the patients treated with unilateral THA was (50.52±24.51) mm. During operation, 19 hips underwent subtrochanteric shortening osteotomy, with an average length of 25 mm (range, 15-35 mm). The Harris score, subjective satisfaction, prosthesis survival rate, complications, and related imaging indicators were summarized. Results All patients were followed up 13.0-19.6 years (mean, 15.0 years). The complications included 1 hip of femoral nerve palsy, 2 hips of dislocation, 1 hip of periprosthetic fracture, 1 hip of periprosthetic joint infection. At last follow-up, the Harris score was 82.1±9.3, which significantly improved when compared with preoperative one (t=−21.885, P=0.000). The subjective satisfaction was evaluated as very dissatisfactory in 3 hips, dissatisfactory in 1 hip, generally in 4 hips, satisfactory in 17 hips, and very satisfactory in 20 hips. X-ray films showed that the height of the greater trochanter of affected side was 3.01-51.60 mm (mean, 23.22 mm); the descending distance of greater trochanter was 3.95-98.06 mm (mean, 48.20 mm); the affected limb lengthened 3.95-61.63 mm (mean, 34.92 mm); the leg length discrepancy of patients treated with unilateral THA was (12.61±8.56) mm, which was significantly shorter than that before operation (t=11.721, P=0.000). The vertical distance between the center of rotation of the affected side and the teardrop line was (14.65±6.16) mm, and the difference was not significant when compared with (15.60±4.99) mm of the healthy side (t=−0.644, P=0.525); the horizontal distance was (22.21±5.14) mm, and the difference was significant when compared with (34.48±5.63) mm of the healthy side (t=−12.973, P=0.000). Except for the non-union of 1 hip subtrochanteric shortening osteotomy, the other subtrochanteric osteotomies healed well. During follow-up, all the femoral stems obtained bone ingrowth fixation without radiolucent line or radiopaque line. With any reoperation and aseptic loosening as the endpoint, the prosthetic survival rates were 88.64% [95%CI (63.73%, 96.82%)] and 89.19% [95%CI (65.61%, 96.94%)], respectively. Conclusion For Crowe type Ⅳ DDH patients, primary THA combined with subtrochanteric shortening osteotomy if necessary, can obtain satisfactory long-term effectiveness and prosthetic survival rate.
ObjectiveTo analyze and summarize the short-term effectiveness of total hip arthroplasty (THA) with a tapered, modular neck hip stem for developmental dysplasia of the hip (DDH). MethodsBetween October 2010 and May 2012, 28 patients (31 hips) with DDH and secondary osteoarthritis underwent THA with a tapered, modular neck hip stem. There were 2 males and 26 females, with an average age of 61 years (range, 47-77 years). The unilateral hip was involved in 25 cases and bilateral hips in 3 cases. According to the Crowe system, 22 cases were classified as Crowe type I, 8 as Crowe type Ⅱ, and 1 as Crowe type Ⅲ. At preoperation, the leg length discrepancy was (1.6±0.8) cm; the hip range of motion values were (76.1±12.8)° in flexion, (14.5±6.7)° in abduction, (9.0±4.5)° in adduction, (13.1±6.4)° in internal rotation, and (11.7±7.0)° in external rotation; and the Harris hip score was 44.7±11.1. ResultsFemoral neck fracture occurred in 2 cases (2 hips) during operation, which healed by fixed with steel wire. The incisions healed by first intention. No related complication occurred. The mean follow-up time was 20 months (range, 12-32 months). At last follow-up, the leg length discrepancy was significant decreased to (1.0±0.5) cm (t=-3.512, P=0.002). The hip range of motion values were (102.9±10.1)° in flexion, (32.9±6.0)° in abduction, (19.2±4.3)° in adduction, (34.4±4.2)° in internal rotation, and (32.3±5.1)° in external rotation, all showing significant differences when compared with preoperative values (P<0.05). The Harris hip score was significantly improved to 90.3±6.1 (t=21.263, P=0.000). The X-ray films showed no subsidence, loosening, or breakage in the other cases except 2 cases having subsidence (<2 mm) within 1 year. Heterotopic ossification occurred in 2 hips. ConclusionThe short-term effectiveness of THA with a tapered, modular neck hip stem for DDH is satisfactory. However, the medium and long-term effectiveness still need further follow-up.
ObjectiveTo explore the effect of false acetabulum on the development and anatomical morphology of proximal femur in Crowe type Ⅳ developmental dysplasia of the hip (DDH), providing a theoretical basis for the development of femoral reconstruction strategy and prosthesis selection for total hip arthroplasty. Methods The medical records of 47 patients (54 hips) with Crowe type Ⅳ DDH between February 2008 and March 2020 were retrospectively analyzed, of which 21 patients (26 hips) were Crowe type Ⅳa (type Ⅳa group) and 26 patients (28 hips) were Crowe type Ⅳb (type Ⅳb group). There was no significant difference in general data such as gender, age, height, weight, body mass index, and side between the two groups (P>0.05), which were comparable. The height of femoral head dislocation, the height of pelvis, and the proportion of dislocation were measured based on preoperative anteroposterior pelvic X-ray film. Based on the preoperative femoral CT scan data, the anatomical parameters of the femur and femoral medullary cavity were measured after three-dimensional reconstruction using Mimics19.0 software to calculate the canal fare index; and the femoral medullary cavity parameters were matched with the modular S-ROM prosthesis parameters. ResultsThe results of X-ray film measurement showed that the height of femoral head dislocation and the proportion of dislocation in type Ⅳa group were significantly higher than those in type Ⅳb group (P<0.05). There was no significant difference in the height of pelvis between the two groups (P>0.05). The results of CT three-dimensional reconstruction measurements showed that compared with the type Ⅳb group, the type Ⅳa group had less isthmus height, smaller femoral head, shorter femoral neck, narrower neck-shaft angle, increased anteversion angle, and higher greater trochanter, and the differences were significant (P<0.05). There was no significant difference in the height of femoral head, femoral offset, and height difference between greater trochanter and femoral head between the two groups (P>0.05). There was no significant difference in the mediolateral width (ML), anteroposterior width (AP), and diameter of the isthmus (Ci level) and the AP of the medullary cavity in the plane 40 mm distal to the most prominent point on the medial side of the lesser trochanter (C–40 level) (P>0.05), and the size of medullary cavity was significantly smaller in type Ⅳa group than in type Ⅳb group at the other levels (P<0.05). Compared with the type Ⅳb group, the difference between the outer diameter of the prosthetic sleeve and the diameter of the medullary cavity fitting circle in the plane where the center of femoral head rotation was located from the medial most prominent point of the lesser trochanter (C0 level) in type Ⅳa group was smaller, and the proportion of negative values was greater (P<0.05). The difference between the longest diameter of the prosthetic sleeve triangle and the ML of the medullary cavity in the plane 10 mm proximal to the most prominent point on the medial side of the lesser trochanter (C+10 level) in type Ⅳa group was smaller, and the proportion of negative values was greater (P<0.05). ConclusionFalse acetabulum has a significant impact on the morphology of the proximal femur and medullary cavity in patients with Crowe type Ⅳ DDH, and the application of three-dimensional reconstruction technique can accurately evaluate the femoral morphology and guide the selection of femoral prosthesis.