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 measure and analyze the radiographic characteristics of the leg length discrepancy in adult patients with unilateral developmental dysplasia of the hip (DDH).MethodsThe clinical data of 112 patients with unilateral DDH who met the selection criteria between January 2016 and June 2018 were retrospectively analyzed. There were 16 males and 96 females with an age of 20-76 years (mean, 42.9 years). According to the Crowe classification, there were 25 hips of type Ⅰ, 26 hips of type Ⅱ, 15 hips of type Ⅲ, and 46 hips of type Ⅳ (26 hips of type ⅣA without secondary acetabular formation, and 20 hips of type ⅣB with secondary acetabular formation). Full-length X-ray films of the lower limbs in the standing position were used to measure the following parameters: greater trochanter leg length (GTLL), greater trochanter femoral length (GTFL), lesser trochanter leg length (LTLL), lesser trochanter femoral length (LTFL), tibial length (TL), and intertrochanteric distance (ITD). The above parameters on the healthy and affected sides were compared and the difference of each parameter between the healthy and affected sides was calculated. Taking the difference of 5 mm between the healthy side and the affected side as the threshold value, the number of cases with the healthy side was greater than 5 mm and the affected side was greater than 5 mm were counted respectively. The difference of the imaging parameters between the healthy side and the affected side were compared between different Crowe types and between type ⅣA and type ⅣB.ResultsThere was no significant difference in GTLL and LTFL between healthy and affected sides (P>0.05); LTLL and TL of affected side were longer than healthy side, GTFL and ITD were shorter than healthy side, and the differences were significant (P<0.05). The constituent ratio of long cases on the affected side of TL and LTLL was greater than the constituent ratio of long cases on the healthy side, while the constituent ratio of long cases on the healthy side of GTFL and ITD was greater than the constituent ratio of long cases on the affected side; there was no obvious difference in the constituent ratio of long cases on the healthy side or the affected side of GTLL and LTFL. The comparison between different Crowe types showed that only the difference in TL between type Ⅰ and type Ⅳ was significant (P<0.05), the difference of each imaging parameter among the other types showing no significant difference (P>0.05). Compared with type ⅣB, the differences of GTLL, TL, and ITD of type ⅣA were bigger, and the differences were significant (P<0.05); the differences of other parameters between type ⅣA and type ⅣB were not significant (P>0.05).ConclusionIn adult unilateral DDH patients, the leg length on the healthy side and the affected side is different, and the difference mainly comes from the TL and ITD, which should be paid attention to in preoperative planning.
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 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.
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.
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.
ObjectiveTo explore the feasibility and effectiveness of total hip arthroplasty (THA) with acetabulum structural bone grafting using autogenous femoral head through direct anterior approach (DAA) in lateral decubitus position in the treatment of Crowe type Ⅲ and Ⅳ developmental dysplasia of the hip (DDH). Methods Between June 2016 and July 2020, 12 patients with Crowe type Ⅲ and Ⅳ DDH were treated with THA with acetabulum structural bone grafting using autogenous femoral head through DAA in lateral decubitus position. There were 2 males and 10 females with an average age of 60.2 years (range, 50-79 years). Crowe classification was type Ⅲ in 10 hips and type Ⅳ in 2 hips. The preoperative Harris score of hip joint was 48.8±7.5, the difference in length of both lower extremities was (3.0±0.7) cm, and the visual analogue scale (VAS) score during activity was 7.2±0.9. The surgical incision length, operation time, intraoperative blood loss, and complications were recorded; the position and press-fitting of acetabulum and femoral prosthesis were observed after operation, and the difference in length of both lower extremities was measured; the horizontal coverage of acetabular cup and bone graft were measured, the healing with the host bone and the loosening of the prosthesis were evaluated; Harris score was used to evaluate hip joint function, and VAS score was used to evaluate patients’ pain during activity. Results The average surgical incision length was 9.3 cm, the average operation time was 117 minutes, and the average intraoperative blood loss was 283 mL. Two patients (16.7%) received blood transfusion during operation. There was no acetabular and femoral fractures during operation. All incisions healed by first intention, without dislocation, periprosthetic infection, sciatic nerve injury, deep venous thrombosis, and other complications. One patient had lateral femoral cutaneous nerve injury after operation. X-ray films at discharge showed a total acetabular cup level coverage of 93%-100%, with an average of 97.8%, and a bone graft level coverage of 25%-45%, with an average of 31.1%. All the 12 patients were followed up 22-71 months, with an average of 42.2 months. At last follow-up, the Harris score of hip joint was 89.7±3.9, the difference in length of both lower extremities was (0.9±0.4) cm, and the VAS score during activity was 1.1±0.6, which were significantly different from those before operation (P<0.05). During follow-up, there was no patient who needed hip revision surgery because of prosthesis loosening. At last follow-up, there was no translucent line between the graft and the host bone, the graft was fused, the position was good, and there was no obvious movement. One patient had one screw fracture and bone resorption at the outer edge of the graft, but the bone graft did not displace and healed well. ConclusionTHA with acetabulum structural bone grafting using autogenous femoral head through DAA in lateral decubitus position in the treatment of Crowe type Ⅲ and Ⅳ DDH is safe and reliable, and has satisfactory short-term effectiveness.
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 evaluate the three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip (DDH) using a semi-automated measurement software, which provides data for the differential diagnosis, surgical planning, surgical instrument design, and postoperative evaluation of hip related diseases. MethodsEighty-four cases of CT data in asymptomatic population (asymptomatic group) and 47 cases of CT data in DDH patients (DDH group) were collected. There was no significant difference in gender and age (including age of male and female subgroups) between the two groups (P<0.05). MaxTHA, a semi-automatic measurement software, was used to measure acetabular inclination and anteversion, including operative inclination (OI), radiographic inclination (RI), anatomic inclination (AI), operative anteversion (OA), radiographic anteversion (RA), and anatomic anteversion (AA). Comparisons were made between the two populations, between different Crowe classification subgroups, between different gender subgroups, and between left and right sides of acetabula. Results The comparison between asymptomatic group, healthy side of DDH group, and affected side of DDH group showed that there was no significant difference in acetabular orientation between asymptomatic group and healthy side of DDH group (P>0.05). The OI, RI, and AI of affected side of DDH group were significantly higher than those in healthy side of DDH group and asymptomatic group, and AA was significantly lower than that in healthy side of DDH group and asymptomatic group (P<0.05). The comparison between the normal acetabula and DDH acetabula with different Crowe classifications showed that there was no significant difference in the acetabulum orientation between Crowe Ⅰ group and the normal group (P>0.05). The OI, RI, and AI of Crowe Ⅱ, Ⅲ, and Ⅳ groups were significantly higher than those of normal group (P<0.05), the OI of Crowe Ⅲ group, RI and AI of Crowe Ⅳ group were significantly higher than those of Crowe Ⅰ group (P<0.05), the AI of Crowe Ⅳ group was significantly higher than that of Crowe Ⅱ group (P<0.05), and the OA, RA, and AA of Crowe Ⅲ group were significantly lower than other subgroups (P<0.05) except Crowe Ⅰ group. The OA, RA, and AA in asymptomatic female group, and the OA and AI in DDH female group were significantly higher than those in all male groups (P<0.05). The OI, RI, AI, and OA of the right acetabula in asymptomatic male group, and the RI and AI of the right acetabula in asymptomatic female group were significantly higher than those on the left side (P<0.05). ConclusionThere were significant differences in acetabular orientation between asymptomatic and DDH populations, inter-group differences among Crowe classification subgroups, inter-gender differences among subgroups, and bilateral differences among asymptomatic individuals.
ObjectiveTo investigate the influence of the degree of acetabular deformity and the learning-curve on the acetabular cup positions in total hip arthroplasty (THA) for adults with developmental dysplasia of hip (DDH). MethodsBetween January 2008 and December 2015, 130 patients (144 hips) with DDH underwent primary THA, and the clinical data were analyzed retrospectively. Fifty-three patients (59 hips) were admitted before 2012, and 77 patients (85 hips) were treated after 2012. There were 32 males and 98 females, aged from 31 to 83 years (mean, 61). Unilateral replacement was performed in 116 cases and bilateral replacement in 14 cases. Of 144 hips, 48 hips were rated as Crowe type I, 57 hips as type II, and 39 hips as type of III/IV. The standard pelvic radiograph was taken within 1 week after operation. The mediCAD software was adopted to measure the angle of anteversion and abduction, bony coverage, and the distance between true rotating center and optimal rotating center to the connection of teardrops and the horizontal distance between two centers to evaluate the qualified rate of acetabular cup positions. ResultsCompared with the patients with the same type in 2013-2015 group, the anteversion angle and qualified rate of acetabular cup position significantly decreased in patients with Crowe I (P < 0.05); the horizontal distance significantly increased and qualified rate of acetabular cup position significantly decreased in patients with Crowe II (P < 0.05); and the anteversion angle significantly decreased and the horizontal distance significantly increased in patients with Crowe III/IV (P < 0.05) in 2008-2012 group. But no significant difference was shown in the other indexes (P > 0.05). In all Crowe types, the vertical distance between the true rotating center and the optimal rotating center increased with the degree of acetabular deformity in both 2008-2012 group and 2013-2015 group, showing significant difference (P < 0.05), but no significant difference was found in the other indexes (P > 0.05). ConclusionFor adults with acetabular dysplasia, there are high potential risks for unsatisfactory acetabular cup positions during primary THA. So it is necessary to evaluate acetabular deformities and to sum up operative experience so as to improve the accuracy of cups installation.