Medial Protrusio Technique in Cementless Total Hip Arthroplasty for Developmental Dysplasia of the Hip: A Prospective 6- to 9-Year Follow-Up of 43 Consecutive Patients

Medium- to long-term clinical efficacy of total hip arthroplasty with structural bone grafting for dysplasia of the hip

BACKGROUND

Patients with dysplasia of the hip (DDH) have different degrees of bone defects above and outside the acetabulum, and anatomically reconstructing the acetabular centre of rotation is difficult in primary total hip arthroplasty (THA).

METHODS

From April 2012 to December 2022, 64 patients (64 hips) with DDH treated with THA with structural bone graft in the superolateral acetabulum were selected. The Oxford hip score(OHS), Barthel index (BI), leg length discrepancy, Wibegr central edge-angle(CE), gluteus medius muscle strength, vertical and horizontal distance of the hip rotation center, coverage rate of the bone graft and complications were used to evaluate the clinical effectiveness of the patients.

RESULTS

All patients were followed up for an average of 7.3±1.9 years. The OHS improved significantly after the operation (P<0.001). The postoperative BI was significantly greater than that before operation (P<0.001). The postoperative leg length discrepancy was significantly lower than that before the operation (P<0.001). Postoperative bedside photography revealed that the height and horizontal distance to the hip rotation center were significantly lower after surgery than before surgery (P<0.001). The postoperative CE was significantly greater than that before surgery (P<0.001). No acetabular component loosening or bone graft resorption was found during the postoperative imaging examination.

CONCLUSIONS

The use of biological acetabular cup combined with structural bone graft in the superolateral acetabulum in THA for DDH can obtain satisfactory medium and long-term clinical and radiological results.

Placement of Standard Sized Acetabular Cup Between True and False Acetabulum in Patients with Crowe III/IV Dysplasia: A Safe Option in THA Without Femoral Osteotomy

Introduction

There is no consensus in literature on the surgical treatment of patients with Crowe type III/IV patients. Each arthroplasty procedure has its own advantages and disadvantages. In this study by placing the acetabular cup between the true and false acetabulum, we aimed to share our experience about criteria of patient selection, surgical technique, and mid-term results of THA (total hip arthroplasty) in which the risk of dislocation was minimized using a standard-sized acetabular cup.

Materials and Methods

We reviewed the clinical and radiographic data of the patients with Crowe type III/IV treated by cementless THA without femoral shortening osteotomy from January 2015 to January 2020. The clinical (Harris hip score, Trendelenburg sign, limb lengths) and radiographic (AP/L hip X-ray, 3D CT) examinations before surgery; 1, 3 months and 1 year after the surgery were evaluated. All postsurgical complications were noted.

Results

Among all, 268 patients met the inclusion criteria. Thirty-two patients (11.9%) were male and 236 (88.1%) were female. Mean age was 46.8 years. Mean follow-up duration was 42.4 (26-57) months. Mean Harris Hip score (HHS) was 49.7 and Trendelenburg sign was positive in all patients preoperatively. In the final evaluation, mean HHS significantly improved to 80.2 (p < 0.005) and none of the patients had Trendelenburg sign. Mean lengthening of the operated leg was 4.3 cm.

Conclusion

Total hip arthroplasty with placement of acetabular cup between true and false acetabulum can be successfully preferred in selected patients with Crowe III/IV dysplasia.

Medial Protrusio Technique Versus Structural Autologous Bone-Grafting Technique in Total Hip Arthroplasty for Crowe Type II to III Hip Dysplasia

BACKGROUND

It is unclear whether acetabular reconstruction techniques have any impact on clinical outcomes. This study aimed to determine (1) whether acetabular reconstruction techniques influenced the position of the acetabular cup and (2) whether clinical outcomes based on the acetabular reconstruction techniques differ in patients undergoing total hip arthroplasty (THA) with Crowe II to III developmental dysplasia of the hip.

METHODS

This was a retrospective analysis of prospectively collected data from 69 patients (74 hips) who were treated with cementless THA using medial protrusio technique (MPT) or structural autologous bone-grafting technique (SABT). There were 39 patients (41 hips) included in the MPT group and 30 patients (33 hips) in the SABT group. Clinical and radiographic outcomes were evaluated.

RESULTS

All patients were followed up for at least 3 years. There were similar results between the 2 groups in terms of blood loss, Harris hip score, leg length discrepancy, cup inclination, cup anteversion, and proportion of cup coverage (P > .05). The operative time was significantly longer in the SABT group compared with the MPT group (P < .001). The postoperative vertical center of rotation was significantly higher in the MPT group compared with the SABT group (P = .001), and postoperative horizontal center of rotation was significantly shallower in the SABT group compared with the MPT group (P < .001).

CONCLUSION

The MPT and SABT provide similar clinical and radiographic outcomes in the management of Crowe II to III developmental dysplasia of the hip by cementless THA. However, the MPT has the advantage of a shorter operative time, whereas the SABT is more conducive to placing the acetabular cup in an anatomic position.

LEVEL OF EVIDENCE

Level III, Therapeutic, Case-Control Study.

Total Hip Arthroplasty in Patients with Crowe III/IV Developmental Dysplasia of the Hip: Acetabular Morphology and Reconstruction Techniques

The severe anatomic deformities render acetabular reconstruction as one of the greatest challenges in total hip arthroplasty (THA) for patients with Crowe III/IV developmental dysplasia of the hip (DDH). Thorough understanding of acetabular morphology and bone defect is the basis of acetabular reconstruction techniques. Researchers have proposed either true acetabulum position reconstruction or high hip center (HHC) position reconstruction. The former can obtain the optimal hip biomechanics, including bulk femoral head autograft, acetabular medial wall displacement osteotomy, and acetabular component medialization, while the latter is relatively easy for hip reduction, as it can avoid neurovascular lesions and obtain more bone coverage; however, it cannot achieve good hip biomechanics. Both techniques have their own advantages and disadvantages. Although there is no consensus on which approach is better, most researchers suggest the true acetabulum position reconstruction. Based on the various acetabular deformities in DDH patients, evaluation of acetabular morphology, bone defect, and bone stock using the 3D image and acetabular component simulation techniques, as well as the soft tissue tension around the hip joint, individualized acetabular reconstruction plans can be formulated and appropriate techniques can be selected to acquire desired clinical outcomes.

Mid-Term Outcomes of Cemented Stem and Subtrochanteric Shortening Derotational Osteotomy in Total Hip Arthroplasty for Crowe IV Developmental Dysplasia

OBJECTIVE

Performing subtrochanteric osteotomy with cemented components in patients with Crowe IV developmental dysplasia of the hip (DDH) is technically challenging and not widely reported. This study aimed to evaluate the mid-term outcomes of cemented stem total hip arthroplasty (THA) with subtrochanteric femoral shortening and transverse derotational osteotomy in patients with Crowe IV DDH.

METHODS

Data collected from patients with Crowe IV DDH who underwent cemented stem THA with subtrochanteric femoral shortening and transverse derotational osteotomy between 2010 and 2018 were retrospectively evaluated. The cemented Lubinus SP II femoral component and the cementless CombiCup acetabular component were used together in all cases. These data, including Harris hip scores, limb length discrepancy (LLD), severity of limp, Trendelenburg test, bone union, length of the resected femur, limb lengthening, level of the osteotomy site, and length bridging the osteotomy site, as well as complications, were analyzed. A paired Student t-test was used to analyze continuous variables, categorical data were compared using Fisher's exact probability test, and correlation analysis was performed using Spearman's rank correlation coefficient.

RESULTS

Among 14 included patients (10 females and four males), the mean age was 60.4 years (range, 47-73). The mean follow-up period was 49.1 months, and no patient was lost to follow-up. The mean Harris hip score improved from 40.7 to 87.7. The mean LLD decreased from 52 to 12.7 mm. The mean length of the excised femoral segment was 38.4 mm, and the mean length of limb lengthening was 27.1 mm. The mean distance between the osteotomy site and the lesser trochanter was 21.1 mm after surgery. The mean length of the femoral stem bridging the osteotomy site was 97.6 mm. Finally, the mean osteotomy union time was 10.6 months. No statistically significant correlation was found between the osteotomy union time and these factors. No neurological deficits were noted. Delayed union was observed in one patient, and postoperative dislocation was observed in two patients. Cement leakage into the osteotomy gap was observed in one patient, however, no revisions were required, and no signs of loosening or migration were observed.

CONCLUSIONS

Cemented stem THA combined with subtrochanteric femoral shortening and transverse derotational osteotomy is safe and effective in treating patients with Crowe IV DDH. Rather than leading to nonunion, cement leakage may negatively affect bone healing.

Revision of a Failed Primary Total Hip Arthroplasty following Excessive Reaming with a Medial Cup Protrusion

Background and Objectives: Atraumatic intrapelvic protrusion of the acetabular component following excessive reaming of the acetabulum with a far medial positioning of the cup is a rare, but serious complication of a total hip arthroplasty (THA). This study analyzes the factors contributing to this uncommon complication and presents the outcome after the revision surgery using the Ganz reinforcement ring combined with a bone graft and plating of the posterior column and/or screws for the anterior column. Materials and Methods: A retrospective case series study with seven patients (four males, mean age 76 ± 10 years (60−86)) that underwent a revision THA within 24 ± 17 days (5−60) after an atraumatic periprosthetic acetabular fracture with a medial cup protrusion was performed. All fractures were reconstructed with a Ganz reinforcement ring and bone graft with a mean follow-up of 1.7 ± 1.7 years (0.5−5). Radiographs were evaluated for the following: (i) cup positioning immediately after the primary THA and the revision surgery, (ii) cup migration in the follow-up, and (iii) fracture healing. Results: The position of the acetabular component as assessed on the postoperative radiographs after the index surgery and before the complete medial cup protrusion showed a cup placement beyond the ilioischial line indicative of a fracture of the medial wall. The revision surgery with the reconstruction of the medial wall with a Ganz reinforcement ring combined with a bone graft restored in the presented cases the center of rotation in the horizontal direction with a statistical significance (p < 0.05). During the follow-up, there was no aseptic loosening with the relevant cup migration or significant change in the position of the acetabular cup at the final follow-up (p > 0.05) after the revision. All seven fractures and bone grafts realized a bone union until the latest follow-up. Conclusions: Following excessive reaming, the acetabular component was placed too far medially and resulted in an intrapelvic cup protrusion. An unstable cup following a fracture of the medial wall was evident on the immediate postoperative radiographs. In the case of the medial wall perforation with an intrapelvic cup protrusion after the primary THA, the reconstruction with a Ganz reinforcement ring was a successful treatment option resulting in the fracture healing and a stable cup positioning. Surgeons should be aware of that rare and probably underreported complication and restore the anatomic center of rotation by treating the defect intraoperatively.

The Clinical and Radiological Outcomes of Subtrochanteric Osteotomy in Crowe Type IV Hip Dysplasia: A Comparison of Three Different Stem Designs

AIMS

The purpose of this study was to determine whether there are differences in clinical and radiographic outcomes among three different stem designs for subtrochanteric osteotomy in Crowe type IV developmental dysplasia of the hip (DDH).

METHODS

A retrospective analysis of prospectively collected data was undertaken from a consecutive series of 37 Crowe type IV DDHs treatment of noncemented total hip arthroplasty with chevron subtrochanteric osteotomy in 30 patients. Patients are divided into three groups, including Ribbed group (using Link Ribbed stem; n = 14), Synergy group (using Synergy stem; n = 9), and Link Classic Uncemented (LCU) group (using LCU stem; n = 14), according to the design of the stem. The clinical and radiographic outcomes were evaluated.

RESULTS

All patients were followed for 36 months. The time of bone union of the LCU stem was significantly longer than that of the Synergy stem (P = 0.02) and the Ribbed stem (P > 0.05); the time of bone union of the Ribbed stem was longer than that of the Synergy stem (P > 0.05). The length of stem in the distal femur of the Ribbed stem (P = 0.000) and the Synergy stem (P = 0.001) is significantly longer than that of the LCU stem. There were three hips with malunion, stem loosening, and varus alignment, which were observed in the LCU stem. None of these were observed in Ribbed and Synergy stems. In total hip arthroplasty with a noncemented stem combined with subtrochanteric femoral osteotomy for Crowe IV DDH, 89.2% hips (33/37) can achieve good and excellent clinical outcomes. There were three hips (1 hip in the Ribbed stem and two in the LCU stem) with fair clinical outcomes and one hip (LCU stem) with poor clinical outcomes.

CONCLUSIONS

Although Ribbed, Synergy, and LCU stems have similar clinical outcomes, the LCU stem has a tendency to a varus position, longer union time, malunion, and stem loosening, when compared with the Ribbed and Synergy stems. We recommend against adoption of the LCU stem for Crowe IV DDH with subtrochanteric femoral osteotomy.

LEVEL OF EVIDENCE

Level III, therapeutic study.

[Effectiveness of structural bone graft in total hip arthroplasty for Hartofilakidis type developmental dysplasia of the hip]

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.

Minimum 10-Year Results of Cementless Ceramic-On-Ceramic Total Hip Arthroplasty Performed With Transverse Subtrochanteric Osteotomy in Crowe Type IV Hips

BACKGROUND

Total hip arthroplasty (THA) performed for developmental dysplasia of the hip is a technically difficult procedure with a high complication rate, especially in the presence of completely dislocated hips. This study aimed to evaluate at least 10 years of follow-up results of cementless, ceramic-on-ceramic (CoC) THA performed with transverse subtrochanteric osteotomy in Crowe type IV hips.

METHODS

We retrospectively reviewed 50 patients' 67 hips that underwent CoC, cementless THA with transverse subtrochanteric osteotomy between 2008 and 2011. Clinical and radiological data of the hips were examined. Clinical results were evaluated using the Harris Hip Score and the Western Ontario and McMaster Universities Osteoarthritis Index.

RESULTS

The mean Harris Hip Score improved from 22.9 ± 9.9 preoperatively to 94.1 ± 8.1 at the final follow-up (P < 0.001). The median Western Ontario and McMaster Universities Osteoarthritis Index score improved from 72 (interquartile range: 17) preoperatively to 2 (interquartile range: 17) postoperatively (P < 0.001). The preoperative mean leg length discrepancy was improved from 4.9 ± 1 cm to 1.5 ± 1 cm in unilateral cases at the last follow-up (P < 0.001). Revision surgery was required because of nonunion in two patients, prosthetic infection in one patient, and aseptic femoral loosening in the other patient. The overall ten-year survival rate was 94% for femoral stems and 98.5% for acetabular components as per Kaplan-Meier survival analysis.

CONCLUSION

Transverse subtrochanteric shortening osteotomy combined with using cementless acetabular and femoral components with a CoC bearing surface promises successful clinical results and high prosthesis survival in the treatment of Crowe IV hips at long-term follow-up.

Controlled fracture of the medial wall versus structural autograft with bulk femoral head to increase cup coverage by host bone for total hip arthroplasty in osteoarthritis secondary to developmental dysplasia of the hip: a retrospective cohort study

Background

Many methods have been proposed to increase cup coverage by host bone during primary total hip arthroplasty (THA) in hip osteoarthritis secondary to developmental dysplasia of the hip (DDH). However, there was no study comparing the results of controlled fracture of the medial wall with a structural autograft with a bulk femoral head.

Methods

Sixty-seven hips classified as Crowe II/III were retrospectively included in this cohort study, which consisted of 33 controlled fractures (group A) and 34 structural autografts (group B). The Harris Hip Scores (HHS) were recorded. The radiological assessments were analyzed. Also, complications are assessed. The paired-sample t test was used for data analysis before and after the operation, while the independent sample T test was used for the comparison between the two groups. The Pearson chi-square test or the Fisher exact test was used to analyze the qualitative comparative parameters. Kaplan-Meier was utilized in the analysis of survivorship with the end points as a revision for any component.

Results

All patients were reconstructed acetabulum at the anatomical location. HHS increased greatly for both groups (p = 0.18). No statistic difference was observed for the two groups in postoperative leg-length discrepancy (0.51 ± 0.29 cm for group A and 0.46 ± 0.39 cm for group B, p = 0.64 ), postoperative height of the hip center (2.25 ± 0.42 cm for group A and 2.09 ± 0.31 cm for group B, p = 0.13), and inclination of the cup (39 ± 4° for group A and 38 ± 3° for group B, p = 0.65 ). The rate of cup coverage for group B (94 ± 2%) was better than for group A (91 ± 5%), (p = .009). The rate of cup protrusio was 48 ± 4% for group A. For both groups, no statistical difference was observed in the cup diameter (p > .05), while group A showed less operation time than group B (p < .001). No complications were observed at the latest follow-up.

Conclusion

Controlled fracture of the medial wall to increase cup coverage by host bone at the anatomical location can act as an alternative technique for DDH Crowe II/III with the advantage of shorter operation time and less technically demanding.

Risk of Dislocation After Total Hip Arthroplasty in Patients with Crowe Type IV Developmental Dysplasia of the Hip

Objective

To investigate whether the risk of dislocation after total hip arthroplasty (THA) in patients with Crowe type IV developmental dysplasia of the hip (DDH) is high and to further identify the risk factors for postoperative dislocation in these patients.

Methods

This retrospective cohort study reviewed Crowe type IV DDH patients undergoing THA between January 2009 and December 2017 in our institution. Each Crowe type IV DDH patient was matched with three Crowe type I, II, or III DDH patients according to gender, side and date of operation. The primary outcome of this study was postoperative dislocation after THA. Occurrence, rate, classification, treatment and outcome of dislocation were documented in detail for all patients. The dislocation rates were compared between Crowe type IV DDH patients and Crowe type I, II, or III DDH patients. Demographic data, implant factors, and surgical factors were compared between the dislocation and no dislocation groups. Multiple logistic regression analysis was used to determine the independent risk factors for dislocation in Crowe type IV hips.

Results

A total of 131 Crowe type IV hips were followed up for a mean of 76.5 ± 28.1 months. Three hundred and ninety‐three Crowe type I, II and III hips, including 261 type I hips, 94 type II hips, and 38 type III hips, were identified as controls and followed up for a mean of 76.4 ± 28.2 months. No significant difference was observed in follow‐up time between two groups (P = 0.804). One or more dislocations occurred in 22 of the 524 dysplasia hips (4.20%). Of the 22 dislocated hips, 20 hips (90.9%) were successfully managed with non‐operative treatment. Two patients (9.1%, one Crowe type I and one Crowe type IV) experienced recurrent dislocation and required revision surgery. Crowe type IV hips had a significantly higher postoperative dislocation rate than type I, II, and III hips (11.45% vs 1.78%, P < 0.001). The use of a 22‐mm femoral head (odds ratio [OR] = 23.55, 95% confidence interval [CI] = 1.901–291.788, P = 0.014), older age (OR = 1.128, 95% CI = 1.037–1.275, P = 0.031), and absence of false acetabulum (OR = 12.425, 95% CI = 1.982–77.879, P = 0.007) were identified as independent risk factors for dislocation in Crowe type IV hips.

Conclusions

Crowe type IV DDH patients were at a high risk of dislocation after THA, and using large femoral heads and improving abductor muscle strength may help decrease the rate of postoperative dislocation in such patients.

Inferomedial Hip Center Decreases Failure Rates in Cementless Total Hip Arthroplasty for Crowe II and III Hip Dysplasia

BACKGROUND

We sought to evaluate the outcomes of cementless acetabular components used in patients with Crowe II and III dysplasia, and to compare outcomes between cups placed within vs outside of an "anatomic" zone. Our specific aims were to (1) plot hip centers in these patients at our institution to characterize "anatomic" vs "nonanatomic" positions, (2) evaluate the association between hip center and radiographic loosening, (3) determine whether hip center was associated with acetabular component revision, and (4) compare patient-reported outcome scores between groups.

METHODS

We retrospectively reviewed 88 primary cementless total hip arthroplasties at a mean follow-up of 10 years (range 2-26 years). Patients were 85% female, with a mean age of 44 years (range 28-61 years) and a body mass index of 27 kg/m² (range 19-42 kg/m²). Medical records and radiographs were reviewed, and a survey was conducted for all patients. Anatomic hip center was defined using the 4-zone system, wherein centers are "anatomic" if they are <1 cm superior and <1 cm lateral to the approximate femoral head center. Cox proportional analyses were used to compare outcomes between groups.

RESULTS

Seventy hips (80%) had an anatomic hip center. Anatomic hips had a lower incidence of radiographic acetabular loosening (0% vs 17%, P = .007) and cup revision (0% vs 28%, P = .0002). There were no differences in Hip Disability and Osteoarthritis Outcome and Joint Replacement Scores (96.2 ± 5 vs 91.9 ± 12, P = .7).

CONCLUSION

The incidence of aseptic loosening and cup revision were lower when hip center was <1 cm superior and 1 cm lateral to the approximate femoral head center.

A simple technique to strengthen the initial and mid-term to long-term stability of the cup during total hip arthroplasty in developmental dysplasia of the hip

Objectives:

To assess the effects of a technique of cup blocking screws combined with impaction bone grafting during total hip arthroplasty (THA) for patients with developmental dysplasia of the hip (DDH).

Methods:

From August 2011 to July 2015, 53 patients (59 hips) with DDH in our hospital were treated with THA using the technique of cup blocking screws combined with impaction particulate bone grafting. These patients were prospectively followed, and the clinical and imaging results were collected.

Results:

Harris hip score (HHS) was raised from 41.24 before surgery to 91.49 at the latest follow-up (p<0.001). Length discrepancy (LLD) was reduced from 28.97 mm before surgery to 6.08 mm after surgery (p<0.001). No loosening of the cup was detected at the last follow-up. The differences were insignificant in cup inclination and rate of cup coverage among the 3 groups of Crowe type II, type III, and type IV DDH (p>0.05).

Conclusion:

The technique of cup blocking screws combined with impaction particulate bone grafting is simple and reliable, and it not only simplifies the attainment of initial stability, but also strengthens the mid-term to long-term stability during THA in DDH.