Objective To summarize the biomechanical characteristics, diagnosis, and hip arthroscopic treatment of borderline developmental dysplasia of hip (BDDH) with Cam-type femoroacetabular impingement (Cam FAI). Methods The literature on BDDH with Cam FAI at home and abroad in recent years was extensively reviewed and analyzed. Results In patients with BDDH and Cam FAI, the femoral neck anteversion angle and femoral neck shaft angle increase, the pelvis tilts, and the acetabulum rotates, resulting in instability of the hip joint. In order to maintain the stability of the hip joint, the direction of biomechanical action of the hip joint has changed, which further affects the anatomical structures such as the proximal femur and acetabular morphology. BDDH with Cam FAI can be diagnosed clinically by combining lateral center edge angle, anterior center edge angle, and acetabular index. BDDH with Cam FAI can be effectively treated through arthroscopic polishing of the edges of the acetabular proliferative bone, excision of Cam malformations, and minimally invasive repair of the glenoid lip and cartilage of the hip joint. Conclusion Currently, there is no unified standard for the diagnosis and treatment of BDDH with Cam FAI. Minimally invasive treatment of the hip under arthroscopy can achieve good early- and medium-term effectiveness, and has certain advantages in repairing and maintaining the integrity of the glenoid lip and suturing/compression joint capsule. However, the long-term effectiveness needs to be further followed up to determine. The timing of surgery, intraoperative bone edge depth polishing, and joint capsule suturing/compression techniques also need to be further explored.
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 investigate revision reasons and prosthesis selection of Crowe Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). MethodsA clinical data of 14 patients (15 hips) with Crowe Ⅳ DDH, who underwent a revision hip arthroplasty between January 2008 and May 2018, was retrospectively reviewed. There were 1 male (1 hip) and 13 females (14 hips). The age ranged from 27 to 63 years (mean, 45.0 years). There were 7 cases of left hip, 6 cases of right hip, and 1 case of bilateral hips. The prosthetic interfaces of primary THA were metal-on-polyethylene (MOP) in 9 hips, ceramic-on-ceramic (COC) in 4 hips, ceramic-on-polyethylene (COP) in 1 hip, and ceramic-on-metal in 1 hip. The time from primary THA to revision was 3-204 months (mean, 65.0 months). The causes of revision included aseptic loosening in 7 hips, dislocation in 3 hips, periprosthetic joint infection in 2 hips, osteolysis in 1 hip, nonunion of osteotomy in 1 hip, and a small-angle of femoral anteversion in 1 hip. Preoperative Harris score was 54.1±17.8 and the range of motion (ROM) of flexion was (92.7±20.2)°. Preoperative X-ray films showed the acetabular bone defect in 11 hips and osteolysis of femoral side in 4 hips. During the revision, the prostheses with COP and COC interfaces were used in 5 hips and 10 hips, respectively. Both acetabular and femoral revisions were performed in 11 hips and only femoral revision was performed in 4 hips.ResultsThe mean operation time was 3.7 hours (range, 1.5-6.0 hours). The mean intraoperative blood loss was 940.0 mL (range, 200-2 000 mL). All patients were followed up 16-142 months (mean, 73.9 months). Postoperative X-ray films showed no difference in inclination and anteversion between primary THA and revision (P>0.05). The height of rotation center and offset after revision were higher than those after primary THA, and the difference in offset was significant (P<0.05). At last follow-up, the Harris score and ROM of flexion were 85.0±7.3 and (115.0±17.0)°, respectively, which were significantly higher when compared with those before revision (t=8.909, P=0.000; t=4.911, P=0.000). Three hips underwent a re-revision operation. All protheses were fixed well and no radiolucent line, loosening, or subsidence was observed at last follow-up.ConclusionThe most common reason for revision in patients with Crowe Ⅳ DDH after THA was aseptic loosening. Due to high activity demand of this population, the prosthesis with MOP interface should be prevented and the prosthesis with COC interface could be alternative. Metal block, cup-cage, and reinforcement ring were reasonable solutions for reconstruction of acetabulum with severe bone defects and have satisfactory effectiveness. S-ROM prosthesis should be the preferred stem for neither primary THA or revision.
ObjectiveTo assess the effectiveness of two osteotomy methods in total hip arthroplasty (THA) for treating Crowe type ⅠV adult developmental dysplasia of the hip (DDH), trochanteric osteotomy and subtrochanteric osteotomy. MethodsA retrospective analysis was made on the clinical data of 36 patients (43 hips) with Crowe type ⅠV DDH undergoing THA between June 2007 and December 2013. In THA, 19 patients (23 hips) underwent trochanteric osteotomy (group A) and 17 patients (20 hips) underwent subtrochanteric osteotomy (group B). There was no significant difference in age, gender, body mass index, side, preoperative Harris score, and limb length difference between 2 groups (P>0.05). The operation duration, bleeding volume, hospitalization duration, intraoperative and postoperative complications were compared between 2 groups. ResultsThere was no significant difference in operation duration, bleeding volume, and hospitalization days between 2 groups (P>0.05). The rate of intraoperative complication was 21.7% (5/23) in group A and 5.0% (1/20) in group B, showing no significant difference between 2 groups (P>0.05). The rate of postoperative complications was 10.5% (2/19) in group A and 22.2% (4/18) in group B, showing no significant difference between 2 groups (P>0.05). Thirty-one patients (37 hips) were followed up 1-7 years (mean, 3 years), including 16 cases (19 hips) in group A and 15 cases (18 hips) in group B. X-ray films showed good position of the prostheses. The Harris score at last follow-up was significantly increased when compared with preoperative score in 2 groups (P<0.05), but there was no significant difference between 2 groups (P>0.05). The postoperative discrepancy of bilateral lower limbs had no significant difference (t=-1.343, P=0.188). ConclusionTHA with trochanteric osteotomy or subtrochanteric osteotomy both can effectively treat Crowe type ⅠV DDH. THA with subtrochanteric osteotomy has an advantage in correcting lower limb discrepancy.
Objective To summarize the characteristics and biomechanical research progress of common acetabular reconstruction techniques in patients with Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip (DDH) undergoing total hip arthroplasty (THA), and provide references for selecting appropriate acetabular reconstruction techniques for clinical treatment of Crowe type Ⅱ and Ⅲ DDH. Methods The domestic and foreign relevant literature on biomechanics of acetabular reconstruction with Crowe type Ⅱ and Ⅲ DDH was reviewed, and the research progress was summarized.Results At present, there are many acetabular reconstruction techniques in Crowe type Ⅱ and Ⅲ DDH patients undergoing THA, with their own characteristics due to structural and biomechanical differences. The acetabular roof reconstruction technique enables the acetabular cup prosthesis to obtain satisfactory initial stability, increases the acetabular bone reserve, and provides a bone mass basis for the possible secondary revision. The medial protrusio technique (MPT) reduces the stress in the weight-bearing area of the hip joint and the wear of the prosthesis, and increases the service life of the prosthesis. Small acetabulum cup technique enables shallow small acetabulum to match suitable acetabulum cup to obtain ideal cup coverage, but small acetabulum cup also increases the stress per unit area of acetabulum cup, which is not conducive to the long-term effectiveness. The rotation center up-shifting technique increases the initial stability of the cup. Conclusion Currently, there is no detailed standard guidance for the selection of acetabular reconstruction in THA with Crowe type Ⅱ and Ⅲ DDH, and the appropriate acetabular reconstruction technique should be selected according to the different types of DDH.
Objective To summarize the effectiveness of acetabulum reconstruction with autologous femoral head structural bone graft in total hip arthroplasty (THA) for Hartofilakidis type Ⅱ developmental dysplasia of the hip (DDH). Methods A clinical data of 24 patients (27 hips) with Hartofilakidis type Ⅱ DDH, who underwent acetabulum reconstruction with autologous femoral head structural bone graft in primary THA between October 2012 and October 2020, was retrospectively analyzed. There were 3 males and 21 females, with an average age of 40 years (range, 20-58 years). The body mass index was 19.5-35.0 kg/m² with an average of 25.0 kg/m². There were 21 cases of unilateral hip and 3 cases of bilateral hips. The hip Harris score was 51.1±10.0. The leg length discrepancy of unilateral hip patients was (19.90±6.24) mm. The intraoperative blood loss, wound healing, and complications were recorded. The postoperative bone union, coverage rates of acetabular prosthesis and bone graft, and aseptic loosening of the prosthesis were evaluated based on X-ray films, and the improvement of hip function was observed by Harris score. Results The intraoperative blood loss was 50-1000 mL (median, 350 mL). All incisions healed by first intention, and no fracture, hematoma, infection, or other complications occurred. Sciatic nerve injury occurred in 1 case (1 hip) and deep venous thrombosis occurred in 1 case (1 hip). All patients were followed up 15-103 months (median, 40.5 months). At last follow-up, Harris score was 92.6±4.1 and the difference was significant when compared with preoperative value (t=−28.043, P=0.000). No hip prosthesis needed revision. X-ray films showed that the coverage rate of acetabular prosthesis was 91%-100% (mean, 97.8%), and the coverage rate of bone graft was 13%-46% (mean, 23.8%). The healing time of bone graft was 3-6 months (mean, 4.7 months). At last follow-up, all bone grafts completely healed without any signs of collapse. There was no graft resorption, ectopic ossification or osteolysis, or obvious aseptic loosening of the acetabular and femoral prostheses. The leg length discrepancy of unilateral hip patients was (2.86±2.18) mm, and the difference was significant when compared with preoperative value (t=17.028, P=0.000). Conclusion For Hartofilakidis type Ⅱ DDH patients, if the lateral acetabular prosthesis not covered by the host bone exceeds 5 mm in primary THA, autologous femoral head can be used for structural bone grafting, and the short- and mid-term effectiveness are favorable.
Objective To investigate the effects of femoral offset and mechanical axis of the lower extremity on hip after osteotomy for adult developmental dysplasia of the hip (DDH). Methods A clinical data of 62 adult patients with DDH (62 hips), who underwent periacetabular osteotomy combined with femoral osteotomy between January 2016 and May 2019 and met selective criteria, was retrospectively analyzed. There were 6 males and 56 females. The age ranged from 18 to 38 years, with an average of 24.4 years. Body mass index ranged from 15.8 to 31.8 kg/m2, with an average of 21.8 kg/m2. There were 44 cases of Hartofilakidis typeⅠ and 18 cases of typeⅡ. According to the modified Tönnis osteoarthritis staging, 46 cases were stage 0 and 16 cases were stageⅠ. There were 13 cases with pelvic anteversion, 40 cases with normal pelvis, and 9 cases with pelvic retroversion. Intraoperative blood loss, length of hospital stay, and complications were recorded. Postoperative hip function was evaluated by Harris score and International Hip Outcome Tool (iHOT) score. The femoral offset, collo-diaphyseal angle, hip-knee-ankle angle (HKA), knee valus angle, CE (Wiberg central-edge angle), anterior CE angle, and acetabular index angle were measured and the osteotomy healing was observed on X-ray films. Patients were grouped according to postoperative femoral offset (≥48 mm or <48 mm) and HKA [varus group (HKA<177°), normal group (HKA 177°-183°), and valgus group (HKA>183°)]. Harris score and iHOT score were compared between groups. Results Intraoperative blood loss ranged from 200 to 1 550 mL, with an average of 476 mL. The length of hospital stay ranged from 8 to 21 days, with an average of 13.3 days. All incisions healed by first intention. All patients were followed up 2.0-4.5 years, with an average of 2.8 years. At 1 year after operation, the Harris score and iHOT score of the hip joint significantly increased when compared with those before operation (P<0.05); there were significant differences in the femoral offset, collo-diaphyseal angle, HKA, knee valus angle, CE angle, anterior CE angle, and acetabular index angle between pre- and post-operation (P>0.05). According to the modified Tönnis osteoarthritis staging, 38 cases were stage 0 and 24 cases were stageⅠ; and there was no significant difference between pre- and post-operation (χ2=2.362, P=0.124). There were 11 cases with pelvic anteversion, 38 cases with normal pelvis, and 13 cases with pelvic retroversion, showing no significant difference when compared with that before operation (χ2=0.954, P=0.623). The pubic branch osteotomy did not heal in 9 cases, proximal femur osteotomy did not heal in 2 cases, and inferior pubic ramus stress fracture occurred in 5 cases. There were significant differences (P<0.05) in the Harris score and iHOT score between femoral offset≥48 mm group (n=10) and femoral offset<48 mm group (n=52). There was no significant difference (P>0.05) in Harris score and iHOT score between varus group (n=13), normal group (n=40), and valgus group (n=9). Conclusion Periacetabular osteotomy combined with femoral osteotomy can improve the femoral offset and mechanical axis of the lower extremity of patients with DDH, and improve the functional score of the hip. However, excessive increase of femoral offset during femoral osteotomy is not desirable, resulting in low postoperative functional score.
ObjectiveTo investigate the early effectiveness of proximal femur reconstruction combined with total hip arthroplasty (THA) in the treatment of adult Crowe type Ⅳ developmental dysplasia of the hip (DDH).MethodsBetween May 2015 and March 2018, 29 cases (33 hips) suffering from Crowe type Ⅳ DDH were treated with proximal femur reconstruction combined with THA. Of the 29 cases, there were 6 males (7 hips) and 23 females (26 hips), aged from 24 to 74 years with an average age of 44.9 years. The preoperative Harris hip score was 44.0±12.0. Gait abnormalities were found in all of the 33 hips with positive Trendelenburg sign, and the lower limb discrepancy was (3.8±1.6) cm. Preoperative X-ray films and CT both indicated serious anatomical abnormalities, including complete dislocation of the affected hip with significant move-up of the greater trochanter, abnormal development of the femoral neck, abnormal anterversion angle and neck-shaft angle, dysplasia of proximal femur and dysplasia of medullary cavity. The operation time, intraoperative blood loss, transfusion rate, and complications were recorded. The Gruen and DeLee-Charnley zoning methods were used to evaluate the aseptic loosening of the prosthesis on X-ray films. The Harris score was used to evaluate hip function. The lower limb discrepancy was calculated and compared with the preoperative value.ResultsThe operation time ranged from 80 to 240 minutes, with an average of 124.8 minutes. The intraoperative blood loss ranged from 165 to 1 300 mL, with an average of 568.4 mL. Seventeen patients (51.5%) received blood transfusion treatment. All the incisions healed by first intention without infection or deep vein thrombosis. All patients were followed up 19-53 months, with an average of 33 months. One patient had posterior hip dislocation because of falling from the bed at 4 weeks after operation, and was treated with manual reduction and fixation with abduction brace for 4 weeks, and no dislocation occurred during next 12-month follow-up. Two patients developed sciatic nerve palsy of the affected limbs after operation and were treated with mecobalamin, and recovered completely at 12 weeks later. Trendelenburg sign was positive in 3 patients and mild claudication occurred in 4 patients after operation. X-ray films showed that all the osteotomy sites healed at 3-6 months after operation, and no wire fracture was observed during the follow-up. The Harris score was 89.8±2.8 and lower limb discrepancy was (0.6±0.4) cm at last follow-up, both improved significantly (t=–22.917, P=0.000; t=11.958, P=0.000). The prosthesis of femur and acetabulum showed no obvious loosening and displacement, and achieved good bone ingrowth except 2 patients who had local osteolysis in the area of Gruen 1 and 7 around the femoral prosthesis, but no sign of loosening and sinking was observed.ConclusionThe treatment of Crowe Ⅳ DDH with proximal femur reconstruction and THA was satisfactory in the early postoperative period. The reconstruction technique of proximal femur can effectively restore the anatomical structure of proximal femur, which is one of the effective methods to deal with the deformity of proximal femur.
ObjectiveTo investigate the early effectiveness of artificial intelligence (AI) assisted total hip arthroplasty (THA) system (AIHIP) in the treatment of patients with Crowe type Ⅳ developmental dysplasia of the hip (DDH).MethodsThe clinical data of 23 patients with Crowe type Ⅳ DDH who met the selection criteria between May 2019 and December 2020 were retrospectively analyzed. There were 3 males and 20 females, the age ranged from 44 to 74 years, with an average of 52.65 years. The absolute value of the lower limbs discrepancy before operation was (15.17±22.17) mm. The preoperative Harris score was 62.4±7.2. The AIHIP system was used for preoperative planning, and the operations were all performed via conventional posterolateral approach. Thirteen patients with difficulty in reduction during operation underwent subtrochanteric shortening osteotomy (SSOT). The operation time, hospital stay, and adverse events were recorded; Harris score was used to evaluate the function of the affected limb at 1 day before operation and 1 week and 6 months after operation; pelvic anteroposterior X-ray film was taken at 1 day after operation to evaluate the position of the prosthesis. The matching degree of prosthesis was evaluated according to the consistency of intraoperative prosthesis model and preoperative planning.ResultsThe matching degree of acetabular cup model after operation was 16 cases of perfect matching, 4 cases of general matching (1 case of +1, 3 cases of –1), and 3 cases of mismatch (all of them were +2), the coincidence rate was 86.96%. The matching degree of femoral stem model was perfect matching in 22 cases and general matching in 1 case of –1, and the coincidence rate was 100%. One patient had a periprosthesis fracture during operation, and was fixed with a wire cable during operation, and walked with the assistance of walking aid at 6 weeks after operation; the rest of the patients walked with the assistance of walking aid at 1 day after operation. The operation time was 185-315 minutes, with an average of 239.43 minutes; the hospital stay was 8-20 days, with an average of 9.96 days; and the time of disengagement from the walking aid was 2-56 days, with an average of 5.09 days. All patients were followed up 6 months. All incisions healed by first intension, and there was no complication such as infection, dislocation, refracture, and lower extremity deep venous thrombosis; X-ray films at 1 day and 6 months after operation showed that the acetabular and femoral prostheses were firmly fixed and within the safe zone; the absolute value of lower limbs discrepancy at 1 day after operation was (11.96±13.48) mm, which was not significantly decreased compared with that before operation (t=0.582, P=0.564). All osteotomies healed at 6 months after operation. The Harris scores at 1 week and 6 months after operation were 69.5±4.9 and 79.2±5.7 respectively, showing significant differences between pre- and post-operation (P<0.05). At 6 months after operation, the hip function was evaluated according to Harris score, and 13 cases were good, 9 cases were fair, and 1 case was poor.ConclusionAIHIP system-assisted THA (difficult to reposition patients combined with SSOT) for adult Crowe type Ⅳ DDH has high preoperative planning accuracy, easy intraoperative reduction, early postoperative landing, and satisfactory short-term effectiveness.
Objective To review research advances of revision surgery after primary total hip arthroplasty (THA) for patients with Crowe type Ⅳ developmental dysplasia of the hip (DDH). Methods The recent literature on revision surgery after primary THA in patients with Crowe type Ⅳ DDH was reviewed. The reasons for revision surgery were analyzed and the difficulties of revision surgery, the management methods, and the related prosthesis choices were summarized. Results Patients with Crowe type Ⅳ DDH have small anteroposterior diameter of the acetabulum, large variation in acetabular and femoral anteversion angles, severe soft tissue contractures, which make both THA and revision surgery more difficult. There are many reasons for patients undergoing revision surgery after primary THA, mainly due to aseptic loosening of the prosthesis. Therefore, it is necessary to restore anatomical structures in primary THA, as much as possible and reduce the generation of wear particles to avoid postoperative loosening of the prosthesis. Due to the anatomical characteristics of Crowe type Ⅳ DDH, the patients have acetabular and femoral bone defects, and the repair and reconstruction of bone defects become the key to revision surgery. The acetabular side is usually reconstructed with the appropriate acetabular cup or combined metal block, Cage, or custom component depending on the extent of the bone defect, while the femoral side is preferred to the S-ROM prosthesis. In addition, the prosthetic interface should be ceramic-ceramic or ceramic-highly cross-linked polyethylene wherever possible. Conclusion The reasons leading to revision surgery after primary THA in patients with Crowe type Ⅳ DDH and the surgical difficulties have been clarified, and a large number of clinical studies have proposed corresponding revision modalities based on which good early- and mid-term outcomes have been obtained, but further follow-up is needed to clarify the long-term outcomes. With technological advances and the development of new materials, personalized prostheses for these patients are expected to become a reality.