Long-Term Results of Cementless Total Hip Arthroplasty With Subtrochanteric Shortening Osteotomy in Crowe Type IV Developmental Dysplasia

Total Hip Arthroplasty in Patients Who Have Crowe Type IV Developmental Dysplasia of the Hip: A Systematic Review

BACKGROUND

Developmental dysplasia of the hip (DDH) is one of the principal causes of secondary hip osteoarthritis, giving rise to considerable pain, impaired mobility, and a reduced quality of life. The optimal approach to managing individuals who have Crowe type IV DDH remains controversial. This study aimed to review the existing literature on the application of total hip arthroplasty (THA) as a treatment modality for Crowe type IV DDH, assessing its efficacy in addressing this severe hip deformity.

METHODS

A comprehensive search across the PubMed, Scopus, and Web of Science databases identified relevant studies. Inclusion criteria encompassed investigations reporting outcomes of THA in Crowe type IV DDH patients. Data extraction and quality assessment were performed independently by 2 reviewers. Utilizing R software, the prevalence of THA complications was analyzed through proportion analysis, employing the inverse variance method.

RESULTS

In this systematic review, a total of 74 studies were included, comprising a collective sample size of 2,829 patients (3,356 hips) diagnosed with Crowe type IV DDH. The posterior or posterolateral approach was the most commonly utilized surgical approach, followed by the lateral Hardinge and direct lateral approaches. The majority of studies have employed subtrochanteric osteotomies. Notably, post-THA, leg length discrepancy decreased, Trendelenburg sign resolved, and back pain was reduced. Patient-reported outcome measures like the Harris Hip Score improved significantly. The pooled prevalence rates of major postoperative complications were also assessed, including dislocation (7.2%), revision (8.7%), intraoperative fractures (10.5%), loosening (5.7%), nerve paralysis (5.6%), deep vein thrombosis (3.6%), infection (3.8%), heterotopic ossification grade 2 and above (6.1%), and a complicated patient rate of 11.0%.

CONCLUSIONS

Synthesizing diverse study data, an overview of THAs performance emerges, demonstrating significant enhancements in function, pain reduction, quality of life, and the correction of substantial leg length discrepancy. While THA has shown positive outcomes, instances of complications have been reported. The decision to undergo THA should involve a collaborative assessment between the surgeon and the patient, considering potential benefits and complications.

Cementless Total Hip Arthroplasty With Paavilainen Femoral Shortening Osteotomy Can Provide Good Results at 10 Years in Patients Who Have Crowe IV Developmental Dysplasia of the Hip

BACKGROUND

The aim of this study was to present the clinical and radiologic results of primary total hip arthroplasty (THA) using the femoral shortening osteotomy technique described by Paavilainen in patients who have Crowe IV developmental dysplasia of the hip.

METHODS

We retrospectively analyzed the results of primary THA using the Paavilainen technique in 335 hips. The mean follow-up was 10.2 years. The degree of limp, leg-length discrepancy, and patient satisfaction were assessed. The Oxford Hip Score was used to examine functional outcomes. A number of radiographic parameters were also assessed.

RESULTS

The most common reason for revision surgery was nonunion of the distally advanced greater trochanter. This complication was observed in 22 hips (6.5%). The 10-year survival for acetabular components, it was 97.3%, and for femoral components was 98.7% with aseptic loosening as the end point, and 85.9% with reoperation for any reason as the end point. Patients demonstrated improved functional outcomes. The mean limb lengthening was 27.8 mm. Nonunion was more common if the contact length of the proximal femoral fragment with the lateral surface of the distal femoral fragment was less than 35 mm.

CONCLUSIONS

Cementless primary THA using the femoral shortening osteotomy technique described by Paavilainen in patients who have Crowe IV dysplasia of the hip demonstrates good clinical and radiologic postoperative results. If the contact between the fragments after osteotomy is less than 35 mm, there is a high risk of nonunion, and supplemental fixation may be warranted.

Mid-term to Long-term Outcomes and Complications of Total Hip Arthroplasty in Patients Who Have Crowe IV Developmental Dysplasia of the Hip: A Systematic Review and Meta-Analysis

BACKGROUND

Severe forms of developmental dysplasia of the hip (DDH) in adulthood often lead to total hip arthroplasty (THA). This study aimed to evaluate the mid-term to long-term outcomes of THA in Crowe type IV DDH cases, which represent a technically challenging and complex patient group.

METHODS

PubMed, EMBASE, Web of Science, and Scopus were searched for observational studies and case series with over 100 months of mean follow-up on adult patients who had Crowe type IV DDH treated with THA. A total of 3,710 records were initially identified, leading to the inclusion of 24 studies in the final analysis. These studies were subjected to quality assessment using the National Institutes of Health (NIH) Quality Assessment tool. Various outcomes including revision rates, leg length discrepancy (LLD), Harris Hip Score (HHS), and complications like periprosthetic joint infections (PJI), dislocations, and nerve injuries were analyzed. A random effects model was employed for statistical analysis, with sensitivity analysis and meta-regression applied in cases of high heterogeneity.

RESULTS

The included studies assessed 1,024 hips with a mean follow-up of 11 years, revealing improvements in HHS and reductions in LLD post-THA. However, notable challenges were noted, including a 10.7% rate of intraoperative fractures, a 1.8% PJI rate, and a 5.8% dislocation rate. Osteolysis and aseptic loosening revisions were observed in 9.1 and 8% of cases, respectively. Heterotopic ossification (HO) occurred in 11.1% of patients. Nerve injury was reported in 4.2% of cases. With the use of meta-regression, some factors for observed heterogeneity were identified.

CONCLUSION

Total hip arthroplasty in Crowe type IV DDH patients presents notable challenges, but can lead to substantial long-term improvements in patient-reported outcomes.

Total Hip Arthroplasty Combined with Proximal Femoral Reconstruction Effectively Treats Severe Hip Deformities: A Novel Osteotomy Technique

OBJECTIVE

Total hip arthroplasty (THA) combined with proximal femoral reconstruction is a novel osteotomy technique developed to address severe hip deformities. There is a paucity of robust clinical and radiological evidence regarding the outcomes of this novel osteotomy technique. This study aimed to evaluate the clinical and radiological outcomes of THA combined with proximal femoral reconstruction during the early follow-up.

METHODS

This is a retrospective case series of 63 hips who underwent THA combined with proximal femoral reconstruction at a single institution between January 2020 and July 2023. The mean age of patients was 39.6 ± 12.6 years. The mean follow-up was 25.6 ± 3.8 months. Surgical characteristics and perioperative variables were evaluated to assess the efficacy of this technique. Harris hip score (HHS) was utilized to evaluate hip function. Leg length discrepancy (LLD) was evaluated in X-ray. The incidence of major adverse events including deep vein thrombosis (DVT), osteolysis, nonunion of the osteotomy, intraoperative femoral fracture, and infection was also evaluated. Paired-samples t-test was used to compare preoperative and postoperative HHS and LLD.

RESULTS

The mean operative time was 125.1 min. The mean size of the acetabular components used was 45.2 mm, and the stem size was 7.5. The primary friction interface was ceramic-on-ceramic, accounting for 92.1% of cases. The average length of hospital stay was 8.5 days. The mean cost of treatment was 46,296.0 Yuan. There was a significant improvement in postoperative HHS (p < 0.001) and LLD (p < 0.001) compared to preoperative values. The incidence of deep venous thrombosis was 4.8%; osteolysis rates for the cup and stem were 4.8% and 6.4%, respectively. The non-union and dislocation rates were 1.6% and 3.2%, respectively. There was no incidence of postoperative infection.

CONCLUSION

The novel osteotomy surgical procedure yields reliable and impressive clinical and radiological outcomes, with minimal complications. We advocate for its use in complex primary THA cases involving severe proximal femoral deformities.

Subtrochanteric Shortening Osteotomy Provides Superior Function to Trochanter Slide Osteotomy in THA for Patients With Unilateral Crowe Type IV Dysplasia at a Minimum of 3 Years

BACKGROUND

Performing THA in patients with high-riding developmental dysplasia of the hip (DDH) is associated with serious complications and technical challenges. Various methods of shortening osteotomy are available to facilitate femoral head reduction during THA in patients with high-riding hips; subtrochanteric shortening osteotomy and trochanteric slide osteotomy plus proximal shortening are the most common techniques. However, which approach is superior remains a topic of controversy.

QUESTIONS/PURPOSES

(1) Is there any difference in clinical outcomes (defined as the Harris Hip Score [HHS] and residual limb length discrepancy) at a minimum of 3 years between subtrochanteric shortening osteotomy and trochanteric slide osteotomy in patients with Crowe Type IV DDH who underwent THA? (2) Is there any difference in the risk or type of complications between the two approaches?

METHODS

We performed a retrospective, comparative study of two groups (subtrochanteric shortening osteotomy versus trochanteric slide osteotomy) matched for sex and preoperative HHS at a minimum of 3 years of follow-up. Between 2010 and 2018, we performed 67 THAs in patients with unilateral Crowe Type IV DDH. During that time, we generally used a trochanteric slide osteotomy for THA in all patients with Crowe Type IV hips and performed subtrochanteric shortening osteotomy when a conical stem was not available. A total of 42% (28) had THA with subtrochanteric shortening osteotomy, and 58% (39) had THA with trochanteric slide osteotomy. Of those, 89% (25) and 74% (29), respectively, were accounted for with complete datasets for possible matching at a minimum of 3 years of follow-up. Patients were matched for gender and preoperative HSS (within 10 points), leaving 22 patients in each group (79% of the subtrochanteric shortening osteotomy group and 56% of the trochanteric slide osteotomy group) for evaluation and analysis. Age (42 versus 46 years), gender (female: 73% versus 73%), preoperative HSS (40 versus 40), and preoperative leg length discrepancy (5.9 versus 5.3 cm) were comparable between the two groups (p > 0.05). The trochanteric slide osteotomy group exclusively received Cone Wagner (Zimmer) implants (100%), while Corail (DePuy Synthes) implants (77%) were the most commonly used in the subtrochanteric shortening osteotomy group. HHS at a minimum of 3 years as well as the presence or absence of a limp and Trendelenburg sign, functional leg length discrepancy, nonunion, nerve palsy, and other surgical complications were recorded and compared between the groups based on data drawn from a longitudinally maintained institutional database.

RESULTS

At a mean follow-up of 73 months, improvement in HHS was greater in the subtrochanteric shortening osteotomy group than in the trochanteric slide osteotomy group (48 ± 4 points versus 36 ± 11 points, mean difference 12 points [95% CI 7 to 17 points]; p < 0.001). Although the preoperative leg length discrepancy was similar between the groups, there was a greater postoperative improvement in the subtrochanteric shortening osteotomy group (44 ± 8 mm and 38 ± 8 mm in the subtrochanteric shortening osteotomy and trochanteric slide osteotomy groups, respectively; p = 0.02). The risk of nonunion was higher with a trochanteric slide osteotomy than with a subtrochanteric shortening osteotomy (23% [5 of 22] versus 0% [0 of 22]; p = 0.048). Other complications, including intraoperative periprosthetic fractures, nerve palsy, heterotopic ossification, revision surgery, and dislocation, did not differ between the groups.

CONCLUSION

In patients with Crowe Type IV hips undergoing THA, surgeons might consider subtrochanteric shortening osteotomy rather than trochanteric slide osteotomy to minimize the risk of nonunion and achieve superior hip function. Better correction of leg length discrepancy may also be possible with subtrochanteric shortening osteotomy. The long-term survivorship of hips after these two techniques, as well as the influence of the specific anatomy of the proximal femur on the choice of technique, remain to be explored in future studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Total Hip Arthroplasty With Subtrochanteric Osteotomy for Crowe IV Dysplasia Using an Extensile Direct Anterior Approach: A Surgical Technique

The direct anterior approach (DAA) has been increasing in popularity for primary total hip arthroplasty (THA). Despite previously documented anatomic limitations to its direct distal extension, alternative exposure methods have been described to safely access the femoral diaphysis and facilitate increasingly complex primary and revision THA scenarios. The DAA has several purported advantages compared to alternative approaches (eg, posterior and lateral-based), including its muscle-sparing nature, use of an internervous plane, and preservation of posterior stabilizing structures. Proponents of the DAA cite decreased postoperative pain, quicker recovery times, potentially lower dislocation rates, ease of intraoperative fluoroscopy, and improved implant placement/restoration of leg lengths. The current literature, however, is sparse when considering the use of this approach in the setting of severely dysplastic hips necessitating a concurrent subtrochanteric shortening osteotomy. When utilizing a posterior approach in this population, previous work from Ollivier and colleagues demonstrated high rates of cementless implant osseointegration and significantly improved clinical outcomes at long-term follow-up. Although relatively few reports of addressing this pathology via the DAA currently exist, initial results are promising. This study seeks to provide a detailed description of a surgical technique for performing primary THA and ipsilateral subtrochanteric shortening osteotomy in this patient population utilizing an extensile DAA.

Subtrochanteric Osteotomy in Direct Anterior Approach Total Hip Arthroplasty for Crowe IV Dysplasia-Surgical Technique and Literature Review

For Crowe IV dysplasia, the clinical efficacy and surgical technique of subtrochanteric osteotomy (SO) within the direct anterior approach total hip arthroplasty (DAA-THA) was a subject of debate. This study aimed to describe the surgical technique and clinical outcomes in 11 cases of SO in DAA-THA and to summarize the relevant literature on this topic. Between June 2016 and June 2023, we retrospectively evaluated patients diagnosed with Crowe IV hip dysplasia at our institution. Criteria identified 11 patients who underwent SO during DAA-THA. Comprehensive data encompassing demographic information, radiological data, prosthetic implant type, and surgical intricacies were collected. In addition, an exhaustive review of existing case series literature was undertaken utilizing the PubMed databases. There were no revisions, deaths, dislocations, or infections. One hip (9.09%) had an intraoperative proximal split fracture, two hips (18.2%) had lower limb deep vein thrombosis, and one hip (9.09%) had symptoms of femoral nerve injury. Radiological data showed improved bilateral femoral offset, leg length discrepancy, and anatomical acetabular. During the mean follow-up of 2.18(1.06-2.46) years, patients demonstrated enhanced functional outcomes, with average changes of 25.2 in the Harris hip score and 47 in the WOMAC score. Reviewing the literature, most studies have favored S-ROM prostheses and transverse osteotomy techniques. Intraoperative fractures were notably frequent, with rates peaking at 25%. Nonunion and nerve injury were secondary common complications. SO via DAA-THA may offer satisfactory clinical and radiographic outcomes, but the literature review underscores the need for heightened awareness of intraoperative fracture risk. Proximal detachment of the vastus intermedius plays a pivotal role in SO exposure through the DAA.

Direct Anterior Approach in Total Hip Arthroplasty for Severe Crowe IV Dysplasia: Retrospective Clinical and Radiological Study

Background and Objectives: total hip arthroplasty (THA) for Crowe IV hip dysplasia poses challenges due to severe leg shortening, muscle retraction and bone stock issues, leading to an increased neurological complication, and revision rate. The direct anterior approach (DAA) is used for minimally invasive THA but its role in Crowe IV dysplasia is unclear. This retrospective study examines if DAA effectively restores hip biomechanics in Crowe IV dysplasia patients with <4 cm leg length discrepancy, managing soft tissue and yielding functional improvement, limb length correction, and limited complications. Materials and Methods: 19 patients with unilateral Crowe IV hip osteoarthritis and <4 cm leg length discrepancy undergoing DAA THA were reviewed. Surgery involved gradual soft tissue release, precise acetabular cup positioning, and stem placement without femoral osteotomy. Results: results were evaluated clinically and radiographically, with complications recorded. Follow-up revealed significant Harris Hip Score and limb length discrepancy improvements. Abductor muscle insufficiency was present in 21%. The acetabular component was accurately placed, centralizing the prosthetic joint's rotation. Complications occurred in 16% of cases, including fractures, nerve issues, and infection. DAA in THA showcased positive outcomes for hip function, limb length, and biomechanics in Crowe IV dysplasia. Conclusions: the technique enabled accurate cup positioning and rotation center adjustment. Complications were managed well without implant revisions. DAA is a viable option for Crowe IV dysplasia, restoring hip function, biomechanics, and reducing limb length discrepancy. Larger, longer studies are needed for validation.

Reduction of High Hip Dislocation With a Distraction Nail and Arthroplasty (Preliminary Results of a Novel Technique)

A novel distraction technique is described for total hip arthroplasty in symptomatic high hip dislocation (Crowe IV) combining an intramedullary motorized lengthening nail with a pelvic support plate to gradually stretch hip soft tissues (distalization) and performing total hip arthroplasty with the cup in the primary acetabulum. Twelve patients (15 hips) were identified in a retrospective study via chart review. Medical records and radiographs were reviewed for details of the initial case parameters, surgical details, magnitude of distalization, duration of treatment, outcomes, and complications. Followed by an average of 67.4 mm of distalization, nearly anatomical cup placement, and equal leg length were achieved in all patients. During distalization, pain level was low with acceptable range of motion. One unplanned surgery and no complications with long-term sequelae occurred.

Transverse subtrochanteric shortening osteotomy with double tension-band fixation during THA for Crowe III-IV developmental dysplasia: 12-year outcomes

BACKGROUND

When performing total hip arthroplasty in patients with severe developmental dysplasia, shortening the femur facilitates reduction while also preventing sciatic or crural nerve injury and excessive length of the operated limb. No consensus exists about the optimal type of implant and best internal fixation procedure, two parameters that directly govern the risk of the most common intraoperative and postoperative complications (diaphyseal fractures, dislocation, non-union). To minimise these risks, we developed a technique combining a transverse subtrochanteric shortening osteotomy, a long ovoid-profiled, cementless stem anchored in the metaphysis, and double tension-band wiring for internal fixation. The primary objective of this study was to evaluate the outcomes of this technique with emphasis on (i) complications and femoral implant survival, (ii) clinical outcomes (functional scores and lower-limb length inequality [LLLI]), and time to healing.

HYPOTHESIS

Our technique is associated with low rates of intraoperative and postoperative complications.

MATERIAL AND METHODS

This single-centre retrospective cohort study included patients who underwent THA with a transverse subtrochanteric shortening osteotomy and fixation using double tension-band wiring to treat severe (Crowe III or IV) developmental hip dysplasia. The femoral implant was a long, ovoid, cementless stem fully coated with hydroxyapatite. We collected the intraoperative and postoperative complications, survival, LLLI, functional scores (Harris Hip Score [HHS] and Forgotten Joint Score [FJS]), patient satisfaction, and radiographic outcomes.

RESULTS

The study included 31 hips in 25 patients. Two patients (2/31 hips, 6.5%) were lost to follow-up, leaving 29 hips for the analysis of postoperative outcomes. Mean follow-up was 13.7±4.2 years (range, 5.8-18.3 years). The four intraoperative complications (4/31, 12.9%) consisted fracture of the diaphysis (2/31, 6.5%), fracture of the greater trochanter (1/31, 3.2%), and sciatic nerve injury followed by a full recovery (1/29, 3.4%). The 8 (8/29, 27.5%) postoperative complications consisted of dislocation (2/29, 6.9%), stem subsidence (2/29, 6.9%), and non-union (4/29, 13.8%). Femoral implant survival at last follow-up was 87.1% (95% CI, 76.1-99.7). The mean HHS increased from 39.6±12.0 (range, 14-61) before surgery to 81.7±13.2 (range, 48-100) at last follow-up (p<0.01). The FJS at last follow-up indicated that the joint was forgotten in 14/29 (48.2%) cases and caused only acceptable symptoms in 9/29 (31.0%) of cases. Clinically significant (≥ 1cm) LLLI was present in 8/29 (27.6%) patients postoperatively compared to 19/29 (65.5%) preoperatively. The mean LLLI decreased from 20.8±19.7mm (range, 0-60mm) to 5.0±7.3mm (range, 0-30mm). Mean time to healing was 4.3±2.4 months (range, 2-11 months).

CONCLUSION

Regarding these complex procedures, this technique was associated with low rates of intraoperative fractures and early postoperative complications. However, femoral stem survival was shorter than in earlier studies and the non-union rate was high, despite satisfactory functional and clinical outcomes.

LEVEL OF EVIDENCE IV

Clinical outcomes of proximal femoral reconstruction technique combined with THA in the treatment of high dislocation secondary to septic arthritis: a retrospective single-center study

PURPOSE

The aim of this retrospective study was to examine the clinical outcomes and complications of proximal femur reconstruction (PFR) combined with total hip arthroplasty (THA) in patients with high hip dislocation secondary to septic arthritis (SA).

METHODS

Between September 2016 to September 2021, we performed a series of 15 consecutive PFR combined with THA on patients with high dislocation of the hip secondary to SA, of these,12 hips were reviewed retrospectively, with a mean follow-up of 2.5 years (range, 1.5-6 years). The mean age of the patients at the time of surgery was 52 years (range, 40-70 years).

RESULTS

All patients were followed up. At 1-year postoperative follow-up, the median HHS increased from 32.50 preoperatively to 79.50 postoperatively. The median VAS decreased from 7 before surgery to 2 at 1 year after surgery. The median LLD reduced from 45 mm preoperatively to 8 mm at 1 year after surgery. The mean operative time 125 ± 15 min (range 103-195 min). Mean estimated blood loss was500 ± 105ml (range 450-870 ml). Mean hospital days 9.5 days (range 6-15 days). Two patients developed nerve injuries that improved after nutritional nerve treatment. One patient had recurrent postoperative dislocation and underwent reoperation, with no recurrence dislocation during the follow-up. There were no cases of prosthesis loosening during the follow-up period. One patient developed acute postoperative periprosthetic joint infection (PJI) that was treated with Debridement, Antibiotics and Implant Retention (DAIR) plus anti-infective therapy, with no recurrence during 2 years of follow-up.

CONCLUSION

This study indicates PFR combined with THA shows promise as a technique to manage high hip dislocation secondary to SA, improving early outcomes related to pain, function, and limb length discrepancy.

Titanium modular stems in total hip arthroplasty due to developmental dysplasia: a registry comparison with single-taper implants

INTRODUCTION

The routine use of proximal femoral modularity was discouraged in total hip arthroplasties (THAs). However, titanium dual-taper (DT) implants may provide some advantages over single-taper (ST) stems in cases of complex deformity. A registry study comparing ST and DT stems in dysplasia was designed, aiming to assess: (1) survival rates at long-term; (2) reasons for revision; (3) the profile of failed implants.

METHODS

The arthroplasty registry RIPO was investigated for cementless THAs performed for dysplasia since 2000. ST implants were compared to titanium-on-titanium DT stems. Demographics and implant features were collected. Survival rates and reasons for revision were compared. The profile of DT stem failures in dysplasia was defined.

RESULTS

6429 implants were included in the study, 3642 ST and 2787 DT. The demographic and implant features of the 2 cohorts were not comparable. The DT cohort achieved higher survival rates at long-term (93.9% vs. 91.6%, p = 0.018). DT implants showed a higher rate of implant breakage (0.6%, p = 0.011) and a lower rate of aseptic loosening (p = 0.005). There were no differences in terms of revisions for dislocation. No metallosis occurred. There were more revisions in DT implants in males <65 years, with a 28-mm head size or smaller.

CONCLUSIONS

Modularity did not result in lower survival rates in dysplastic patients and may even reduce the rate of aseptic loosening in comparison to ST stems. The rate of implant breakage is not negligible. Younger males are not good candidates for titanium DT stems.

Three-dimensional femur morphology analysis for the optimal location of subtrochanteric osteotomy with an implanted Wagner cone stem in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip

BACKGROUND

This study aimed to accurately evaluate the matching of proximal and distal femoral segments and fitting of the femur-femoral stem in patients with Crowe type IV developmental dysplasia of the hip (DDH) who have undergone subtrochanteric osteotomy at different locations with an implanted Wagner cone stem to improve the rate of the bone union at the osteotomy site.

METHODS

Three-dimensional femur morphology of 40 patients with Crowe type IV DDH was evaluated at each cross-section to determine the femoral cortical bone area. This study focused on five osteotomy lengths (2.5, 3, 3.5, 4, and 4.5 cm). The overlapped area between the proximal and distal cortical bone segments was defined as the contact area (S, mm²), and the contact area to distal cortical bone area ratio was defined as the coincidence rate (R). Three indicators were used to evaluate the matching and fitting of the osteotomy sites with the implanted Wagner cone stems: (1) higher S and R between the proximal and distal segments; (2) the effective fixation length of the femoral stem at the distal segments being at least 1.5 cm; and (3) osteotomy did not involve the isthmus.

RESULTS

In all groups, S significantly decreased in the two proximal levels above the 0.5 cm level below the lesser trochanter (LT) compared with those below this level. In comparison, at osteotomy lengths from 2.5 to 4 cm, R significantly decreased in the three proximal levels. The optimal osteotomy levels ranged from 1.5 and 2.5 cm below the LT for an appropriately sized stem.

CONCLUSIONS

Subtrochanteric osteotomy at the optimal level not only ensures fitting of the femur-femoral stem but also meets the requirements of a higher S and R to ensure adequate reduction and stabilization at the osteotomy site, which may contribute to the bone union. Although the optimal osteotomy level varies with the size of the femoral stem and the length of the subtrochanteric osteotomy, the optimal osteotomy levels for an appropriately sized Wagner cone femoral stem implantation range from 1.5 to 2.5 cm below the LT.

Postoperative hip center position is associated with gait symmetry in range of axial rotation in dysplasia patients after THA

Background

This study aimed to explore whether pre- or postoperative hip structures or surgical changes significantly influence hip range of motion (ROM) symmetry in patients with hip dysplasia during gait after total hip arthroplasty (THA) and provide possible surgical suggestions.

Methods

Fourteen patients with unilateral hip dysplasia underwent computed tomography before and after surgery to create three-dimensional hip models. Pre- and postoperative acetabular and femoral orientations, hip rotation centers (HRC), and femoral lengths were measured. Bilateral hip ROM during level walking after THA was quantified using dual fluoroscopy. The ROM symmetry in flexion-extension, adduction-abduction, and axial rotation was calculated using the symmetry index (SI). The relationship between SI and the above anatomical parameters and demographic characteristics was tested using Pearson's correlation and linear regression.

Results

The average SI values for flexion-extension, adduction-abduction, and axial rotation during gait were -0.29, -0.30, and -0.10, respectively. Significant correlations were detected mainly in the postoperative HRC position. A distally placed HRC was associated with increased SI values for adduction-abduction (R = -0.47, p = 0.045), while a medially placed HRC was associated with decreased SI values for axial rotation (R = 0.63, p = 0.007). A regression analysis indicated that horizontal HRC positions significantly determined axial rotational symmetry (R² = 0.40, p = 0.015). Normal axial rotation SI values were achieved with HRC between 17 mm medially and 16 mm laterally.

Conclusions

Postoperative HRC position was significantly correlated with gait symmetry in the frontal and transverse planes in patients with unilateral hip dysplasia after THA. Surgical reconstruction of the HRC to between 17 mm medially and 16 mm laterally may contribute to gait symmetry.

Mid-term low back pain improvement after total hip arthroplasty in 306 patients with developmental dysplasia of the hip

BACKGROUND

Low back pain (LBP) from hip and spinal disorders has been one of the main reasons for visiting physicians in patients with developmental dysplasia of the hip (DDH). It is essential to identify the LBP improvement among all grades of DDH patients treated with total hip arthroplasty (THA) at 5-year follow-up.

METHODS

The study included 407 hips of 306 patients (38 males, 268 females) who underwent THA between July 2007 and December 2016. There were 65 hips in Crowe I, 61 hips in Crowe II, 69 hips in Crowe III, and 212 hips in Crowe IV. One hundred and fourteen hips received subtrochanteric shortening. Patients included 101 bilateral THA (BTHA) and 205 unilateral THA (UTHA). The evaluation was performed through Back Pain Function Scale (BPFS), Harris hip score, Visual Analogue Scale (VAS), operative data and radiographic examinations.

RESULTS

The BPFS in patients of unilateral Crowe III and IV relieved significantly more (p < 0.05). However, the BPFS in patients with bilateral symmetry DDH hips relieved significantly less than other groups of DDH hips (p < 0.05). Harris in hips of Crowe II improved significantly more (p < 0.05). The VAS in hips of Crowe II and III improved significantly more (p < 0.05). The unilateral THA surgical time, blood loss, blood transfusion, and osteotomy number and length in Crowe IV were significantly more (p < 0.05).

CONCLUSION

THA is reliable to relieve LBP in DDH patients of unilateral Crowe III and IV; however, in patients with unilateral Crowe I, Crowe II, and bilateral DDH hips, the LBP improvements were limited. This should assist shared decision-making between orthopedic surgeons and patients.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Extra-articular Blocking Technique to Resolve Severe Acetabular Bone Defect in Developmental Dysplasia of the Hip

OBJECTIVE

The reconstruction of acetabular bone defect in developmental dysplasia of the hip (DDH) is a great challenge. Although several successful solutions have been raised, their efficacy and reliability have not been fully substantiated. This work aims to present a simple, economic and effective acetabular reconstructive technique to resolve the massive acetabular bone defect in DDH scenario.

METHODS

This is a case series and observational study investigating the effectiveness and safety of extra-articular blocking technique in patients diagnosed as DDH of Crowe type II-III and Hartofilakidis B. Sixteen consecutive patients indicated for extra-articular blocking and treated with total hip arthroplasty were enrolled in this series from January 2019 to August 2020. The outcome measures included the surgical indicators such as acetabular coverage, prosthesis position, operational time, medical cost, and short-term follow-up indicators such as complications profile, patient-reported functional scales, overall recovery after surgery, and radiographic bone integration and remodeling. Their medical documentation and follow-up records were carefully reviewed with ethical approval.

RESULTS

The mean values of postoperative acetabular component inclination and anteversion were 42.3° ± 2.1° and 16.4° ± 1.8°, with an average acetabular coverage of 92.1%. The mean cost reduction for patients treated with this technique compared with those treated with trabecular metal augmentation was 15.3%. The mean time until walking under full-weight bearing decreased by 3.5 weeks compared with patients treated with autologous bone grafting. Within an average observational period of 18 months, the mean improvements in Harris hip score and WOMAC score were 31 and 22 points, respectively, which were identical to those with bone graft and metal augmentation techniques. No complications such as dislocation, acetabular loosening, periprosthetic joint infection, and limb length discrepancy were recorded. No signs of translucent line formation, third-party reaction, and wear-associated osteolysis were identified.

CONCLUSION

The extra-articular blocking can work simply and effectively to address acetabular bone defect in DDH patients of Crowe II-III and Hartofilakidis B, as evidenced by cost-effectiveness and instant weight-bearing advantages, low failure rate, and early osteointegration and remodeling.

Implant loosening following THA with S-ROM prosthesis and subtrochanteric osteotomy: Three case reports

Prosthesis loosening after THA is a rather common complication. For DDH patients with Crowe IV, the surgical risk and complexity is significant. THA with S-ROM prosthesis combined with subtrochanteric osteotomy is a common treatment. However, loosening of a modular femoral prosthesis (S-rom) is uncommon in THA and has a very low incidence. With modular prostheses distal prosthesis looseness are rarely reported. Non-union osteotomy is a common complication of subtrochanteric osteotomy. We report three patients with Crowe IV DDH who developed prosthesis loosening following THA with an S-ROM prosthesis and subtrochanteric osteotomy. We addressed the management of these patients and prosthesis loosening as likely underlying causes.

Mid-term outcomes after total hip arthroplasty in 106 Crowe II/III hips: different hip center positions

BACKGROUND

Under the obvious acetabular superolateral bone defect of Crowe II/III hips, this study aimed to investigate the difference in surgical technique of different hip center positions from the surgical data and clinical outcomes.

METHODS

From July 2007 to December 2016, 87 patients (106 Crowe II/III hips) consecutively received total hip arthroplasty (THA). The minimum follow-up time was 5 years. The mean limb length discrepancy was 1.97 ± 1.81 cm. Twenty-four hips had surgical histories. The patients were divided into three groups according to the acetabular prosthesis positions, depending on the Crowe classification, respectively, group 1 (Crowe I), group 2 (Crowe II) and group 3 (Crowe III). The surgical data and clinical results were used to evaluate the outcome of different surgical techniques of different hip center positions, including surgical time, blood loss, blood transfusion, number of osteotomy hips, osteotomy length, the distribution of prothesis, postoperative inpatient days, Harris hip scores, Visual Analogue Scale (VAS), Back Pain Function Scale (BPFS) and complications.

RESULTS

The mean follow-up time was 8.93 ± 2.55 years. Nineteen hips performed intraoperative osteotomy. From group 1 to group 3, the mean osteotomy length were 0.53 ± 1.11 cm, 0.05 ± 0.22 cm, and 0.00 ± 0.00 cm, respectively (p = 0.083); the surgical time were 142.57 ± 57.94 min, 118.4 ± 41.22 min, and 120.00 ± 84.85 min, respectively (p = 0.324); the blood loss were 498.21 ± 368.53 mL, 333.33 ± 167.62 mL, and 350.00 ± 212.13 mL, respectively (p = 0.255); the blood transfusion were 288.48 ± 381.68 mL, 128.00 ± 235.17 mL, and 385.00 ± 219.20 mL, respectively (p = 0.199); the postoperative inpatient days were 7.95 ± 4.42 d, 7.47 ± 4.29 d, and 6.50 ± 0.71 d, respectively (p = 0.831). Among the groups, the distribution of acetabular prosthesis, acetabular liner, acetabular prosthesis sizes, femoral head sizes and femoral prothesis distal sizes were not significantly different (p > 0.05). Only the distribution of femoral prosthesis was significantly different (p = 0.046); the Harris, VAS, BPFS, and the distribution of complications were not significantly different (p > 0.05).

CONCLUSIONS

We provided a framework to guide decision-making in Crowe II/III hips for surgeons: the surgical technique of different hip center positions was stable and had good outcomes, but the acetabular prothesis position and femoral prothesis should be determined according to the intraoperative situation.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Total Hip Arthroplasties for Hartofilakidis Type C1 and C2 High Hip Dislocations Demonstrate Similar Survivorship and Clinical Function at Minimum 10-year Follow-up With Cementless Implants

BACKGROUND

This study aimed to determine the differences in survivorship, clinical function, and complications among patients who have Hartofilakidis Type C1 or C2 developmental dysplasia of the hips and underwent total hip arthroplasty (THA) with cementless implants.

METHODS

This retrospective study identified 84 Hartofilakidis Type C hips that underwent THA between 2002 and 2011 with a minimum 10-year follow-up (mean, 13 years, range, 10 to 19 years). Survivorship, latest Harris Hip Scores and satisfaction levels, radiographic outcomes (eg, implant stability, rate and length of subtrochanteric shortening transverse osteotomy, leg-length discrepancy, cup position, and orientation), as well as complications (eg, dislocation, periprosthetic fracture, periprosthetic joint infection) were compared to analyze the differences between Hartofilakidis C1 and C2 hips.

RESULTS

Between C1 and C2 hips, no difference existed in the 15-year cumulative Kaplan-Meier survivorship, with the endpoint defined as any reoperation (93.1 versus 90.8%), aseptic loosening combined with periprosthetic joint infection (93.1 versus 96.2%), or aseptic loosening (94.8 versus 96.2%), latest Harris Hip Score (87.1 versus 86.1%), vertical (6.1 versus 6.0 mm) and horizontal (11.5 versus 10.3 mm) distance to the anatomic center of rotation, postoperative leg length discrepancy (11.2 versus 15.5 mm), dislocation (5.2 versus 11.5%), stem aseptic loosening (6.9 versus 7.7%), periprosthetic fracture (3.4 versus 7.7%), and intraoperative femoral fracture (32.8 versus 23.1%). However, Type C2 hips demonstrated more severe preoperative leg length discrepancy (66.9 versus 42.5 mm) and required a higher percentage of subtrochanteric shortening transverse osteotomies (84.6 versus 36.2%) that were longer (33.7 versus 26.47 mm) than the Type C1 hips.

CONCLUSION

With cementless cups positioned near the anatomic acetabular center and cementless stems combined with subtrochanteric shortening transverse osteotomies, THAs for the Hartofilakidis Type C1 and C2 hips demonstrated similar survivorship, clinical function, and complications.

Direct anterior versus posteriorlateral approachs for clinical outcomes after total hip arthroplasty in the treatment of severe DDH

BACKGROUND

The total hip arthroplasty (THA) has gained popularity in in the treatment of severe developmental dysplasia of the hip (DDH). the posterior lateral approach (PLA) has good clinical efficacy and has been confirmed by the majority clinicians. Nevertheless, controversy exists regarding longer-term benefits of the direct anterior approach (DAA). The objective of this study was to investigate the clinical efficacy and placement of S-ROM prosthesis in the treatment of severe DDH by The total hip arthroplasty (THA) with different surgical approaches.

METHODS

A retrospective analysis was performed on 42 patients with severe DDH admitted to our hospital from August 2015 to February 2022, who were treated with S-ROM prosthesis for total hip arthroplasty and subtrochanteric osteotomy of the femur. They were divided into DAA group and PLA group according to different surgical approaches. Perioperative indicators and imaging data were collected.

RESULTS

The surgery time, intraoperative blood loss, and creatine kinase difference in DAA group and PLA group was without a statistically significant difference (P > 0.05). The postoperative length of hospitalization was shorter in the DAA group than in the PLA group (6.50 ± 3.15 vs 9.18 ± 4.93, P = 0.045). The acetabular abduction angles、the acetabular anteversion angles, the safe area ratio, The difference of femoral eccentricity, and the vertical difference of rotation center in DAA group and PLA group, there was no statistical significance (P > 0.05). Statistically significant differences were detected the horizontal difference of rotation center (P = 0.044).

CONCLUSIONS

Total hip arthroplasty with S-ROM prosthesis is a feasible procedure for severe dysplastic DDH. The clinical efficacy and prosthesis placement parameters of DAA approach are advantage to those of PLA approach.

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.

Total Hip Arthroplasty With Subtrochanteric Osteotomy for Developmental Hip Dysplasia: A Long-term Follow-up Study

Background

Total hip arthroplasty (THA) for developmental hip dysplasia (DDH) often requires a subtrochanteric shortening derotational osteotomy (SDO) to limit leg lengthening, mitigate risk of peripheral nerve palsy, and reduce excessive femoral anteversion. Few studies exist detailing long-term clinical outcomes and survivorship. The aim of this study is to analyze the long-term outcomes and survivorship of an SDO-THA cohort.

Methods

We retrospectively reviewed all patients who underwent cementless THA with femoral osteotomy due to Crowe I-IV DDH between 1991 and 2001. Primary outcome measures included revision surgery for any reason and functional outcome measures using modified Harris Hip scores. Secondary outcome measures included mode of implant failure and radiographic assessment for osteotomy union, polyethylene wear, osteolysis, and implant loosening.

Results

Our review resulted in 24 SDO-THA cases in 20 patients with a mean follow-up of 19 years (range, 8-27 years). Overall survivorship was 67%. All 8 failures were treated with acetabular revision at a mean time to revision of 11 years (range, 1-25 years). Of the failures, there were 5 cases due to polyethylene wear (62.5%), 2 cases due to acetabular loosening (25%), and 1 case due to recurrent instability (12.5%). The mean postoperative modified Harris Hip score was 76 (range, 52-91) with long-term improvement of 43 points maintained (P < .001).

Conclusions

THA with SDO can produce durable long-term outcomes for the patient with DDH. It is important to consider some common reasons for revision, namely polyethylene wear and osteolysis, acetabular loosening, and recurrent acetabular dislocations.

Effect of Hip Joint Center on Multi-body Dynamics and Contact Mechanics of Hip Arthroplasty for Crowe IV Dysplasia

OBJECTIVE

To investigate the hip joint forces, Von Mises stress, contact pressure and micro-motion of hip prosthesis for developmental dysplasia of the hip (DDH) patients under different hip joint centers using musculoskeletal (MSK) multi-body dynamics and finite element analysis.

METHODS

Both MSK multi-body dynamics model and finite element (FE) model were based on CT data of a young female DDH patient with total hip replacement and were developed to study the biomechanics of the S-ROM hip prosthesis. The same offset of hip joint center along all six orientations compared with the standard position was set to predict its effects on both MSK multi-body dynamics and contact mechanics during one gait cycle.

RESULTS

The hip joint forces in the entire walking gait cycle showed two peak values and clear differences between them under different hip joint centers. The hip joint force increased when the hip joint center moved posteriorly (2101 N) and laterally (1969 N) to the anatomical center (1848 N) at the first peak by 13.7% and 6.6%, respectively. The hip joint force increased sharply when the hip center deviated laterally (2115 N) and anteriorly (2407 N), respectively, from the standard position (1742 N) at the second peak. For the sleeve of the S-ROM prosthesis, the maximum Von Mises stress and contact pressure of the sleeve increased if the hip joint center deviated from the anatomical center posteriorly at the first peak. However, the Von Mises stresses and contact pressure increased at anterior and lateral orientations, compared to that of the standard position at the second peak. Small changes were observed for the maximum relative sliding distance along most of the orientations at both peaks except in the lateral and medial orientations, in which an increase of 8.6% and a decrease of 13.6% were observed, respectively.

CONCLUSION

The hip joint center obviously influenced the hip joint forces, stress, contact pressure and micro-motion of the hip implant for this female patient.

[Short-term effectiveness of structural bone graft and total hip arthroplasty through direct anterior approach in lateral decubitus position for Crowe type and developmental dysplasia of the hip]

Objective

To 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.

Conclusion

THA 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.

Clinical and Radiological Outcomes of Revision Total Hip Arthroplasty for Patients with Prior Hartofilakidis Type C Hip Dysplasia

OBJECTIVE

To investigate the clinical and radiological results of revision total hip arthroplasty (THA) for patients with previously diagnosed Hartofilakidis type C hip dysplasia, which is technically challenging and lacks literature.

METHODS

We enrolled 20 patients with previously diagnosed Hartofilakidis type C hip dysplasia who underwent revision THA between November 2008 and July 2015 at our hospital. Patients were followed up for an average of 87 months. Data pertaining to the Harris hip score (HHS), modified Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), general satisfaction, and the level of satisfaction related to 16 hip functions or issues experienced after revision THA were collected. The vertical and horizontal center of rotation (COR) of the hips were measured bilaterally based on preoperative and postoperative anteroposterior radiographs. Categorical variables were analyzed by the chi-square test. Continuous variables were analyzed using the student's t test or non-parametric Wilcoxon Rank Sum test.

RESULTS

There were significant postoperative improvements in the HHS (47.4 ± 31.6 vs 70.1 ± 39.0), modified WOMAC (48.5 ± 27.9 vs 75.7 ± 36.8), and the vertical (45.7 ± 33.7 mm vs 21.6 ± 21.8 mm) and horizontal (41.8 ± 17.0 mm vs 31.4 ± 14.7 mm) offset of the COR after revision THA (P < 0.05). Fifteen (75.0%) patients were satisfied with the procedure. The satisfaction rate for each of the 16 items ranged from 45% to 100%. The top three dissatisfactory items were squatting, getting into/out of cars, and leg-length discrepancy. Postoperatively, dissatisfied patients had a significantly higher visual analogue scale pain score and lower WOMAC pain, HHS pain, WOMAC total, and HHS total scores, a lower satisfaction rate for pain relief, and a higher vertical COR.

CONCLUSION

There is a high rate (25%) of dissatisfaction with the outcome after revision THA for patients with prior Hartofilakidis type C hip dysplasia. The most likely reasons for dissatisfaction were inadequate pain relief and a higher vertical COR measured on radiography.

[Three-dimensional morphological study of the effect of false acetabulum on the femoral structure in Crowe type developmental dysplasia of the hip]

Objective

To 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.

Results

The 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 (C 0 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).

Conclusion

False 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.

Intraoperative two-stage evaluation of muscle contractures in Crowe type IV hips in total hip arthroplasty (a new surgical technique)

BACKGROUND

It is important to maintain soft-tissue balance and prevent muscle contractures after hip reduction during total hip arthroplasty (THA) in patients with Crowe type IV developmental dysplasia of the hip (DDH). To make such hips functional and durable, the techniques to achieve soft-tissue balance were studied to create an algorithm for intraoperative 2-stage evaluation of muscle contractures, specifying the optimal order for contracture release.

METHODS

Between February 2011 and March 2015, we evaluated 64 patients (75 hips) with DDH for muscle contractures as they underwent THA. Following acetabular implantation, femoral osteotomy was applied of various lengths according to limb-length discrepancy. First, the distal part of the femur was prepared by broaching, and the hip was then reduced. The tensor fascia lata, rectus femoris, sartorius, hamstrings, and adductor muscles were evaluated, and any contractures were released. A trial conjoining of the distal and proximal parts of the femur was made, and the hip was reduced again. Finally, the iliopsoas and abductor muscles were evaluated, and contractures were released.

RESULTS

The mean follow-up duration was 4.6 years. Preoperative and postoperative Harris Hip Scores were 52 and 87, respectively. Limb-length discrepancy was mean 4.2 cm preoperatively, and <1 cm postoperatively. All contractures were released according to our newly developed algorithm.

CONCLUSIONS

It is challenging to pinpoint the main muscle causing contractures, because other muscles acting on the hip joint have similar secondary functions. The method we describe here may provide better and more specific restoration of muscle function in a hypoplastic hemipelvis in DDH.

Cementless modular total hip arthroplasty with subtrochanteric transverse shortening osteotomy for high hip dislocations

Background

Performing a total hip arthroplasty for a high hip dislocation is technically demanding and presents several challenges, with appropriate evaluation of the bone morphology of the hip and proper implant selection being critical for successful outcomes.

Objective

The purpose of our study was to evaluate the clinical and radiographic outcomes of cementless modular total hip arthroplasty for the treatment of high hip dislocations with sub-trochanteric transverse shortening osteotomy.

Methods

Sixty-eight hips with a high hip dislocation, were treated using a sub-trochanteric transverse shortening osteotomy and cementless modular total hip arthroplasty, retrospectively reviewed. Hip function was assessed using the Harris hip score, with hip abduction strength evaluated using the Trendelenburg test. Radiographic assessment included the measurement of leg length discrepancy, identification of implant loosening, localization of the hip center, and union at the osteotomy site.

Results

The mean follow-up period was 12.9 (range 5.2–16.8) years. The mean Harris hip score improved from a pre-operative score of 48.6 ± 3.6 to 82.4 ± 4.2 (p < 0.05). The hip was within the true acetabulum in all patients, postoperatively. Osteotomy union was achieved in 67 of the 68 hips (98.5%) in a mean latency of 12.5 ± 0.6 weeks. The mean length of femoral shortening was 66.5 ± 4.5 mm, with a mean pull-down length of the proximal part of 35.5 ± 3.5 mm.

Conclusion

For the treatment of high hip dislocations with satisfactory clinical outcomes, the modular stem offers an adjustable anteversion angle to restore sufficient rotational stability and the transverse osteotomy provides sufficient compression pressure across the osteotomy site to facilitate union.

Trial registration It was a retrospective study and approved by Istanbul Research and Training Hospital institutional Ethics Review Board (772-05/02/2016).

Total joint replacement of the hip and knee in patients with arthrogryposis multiplex congenita: a report of six joints

INTRODUCTION

Arthrogryposis multiplex congenita (AMC) is a rare congenital condition that leads to severe joint contractures and deformities. As painful joint dysplasia and degeneration might develop over time, total joint replacement (TJR) can be a potential treatment option for these patients. The aim of this study is to investigate functional results, implant survivorship and potential complications in patients with AMC who undergo hip or knee arthroplasty.

MATERIALS AND METHODS

We retrospectively identified six TJR in three patients at a single centre performed between 2006 and 2019. The median patient age at surgery was 23 years and the median follow-up period was 69 (IQR 55-99) months. We analysed surgical technique, implant survivorship and complications as well as functional outcome determined by pain reported on the Numerical Rating Scale (NRS), patient-reported outcome scores [Oxford Hip Score (OHS), Harris Hip score (HHS), Oxford Knee Score (OKS)], range of motion and ambulatory status. Depending on data distribution means with ranges and median with interquartile range were compared with the Wilcoxon signed rank test or Student's t test. The level of significance was defined at < 0.05.

RESULTS

In hips, the mean range of motion in flexion/extension (52° vs. 85°, p = 0.014) and in rotation (28° vs. 68°, p = 0.02) as well as mean pain score on the NRS (8.5 vs. 0, p = 0.001), OHS (9 vs. 26, p = 0.031) and HHS (17 vs. 52, p = 0.007) significantly improved. In knees, mean range of motion (55° vs. 93°, p = 0.403), mean pain score on the NRS (0 vs. 7) and the OKS (2 vs. 21) also improved. While the ambulatory status did not change, the patients who were wheelchair dependent reported less problems with transfers to a bed or chair and the patient who ambulated reported an improved walking distance. One total knee arthroplasty (TKA) underwent revision for an acute, late infection 155 months following the initial surgery.

CONCLUSIONS

TJR is a safe procedure in patients with AMC that effectively improves function and reduces pain irrespective of preoperative ambulatory status.

Total Hip Arthroplasty With the Wagner Cone Femoral Stem in Patients With Crowe IV Developmental Dysplasia of the Hip: A Retrospective Study

BACKGROUND

The aim of this study is to assess treatment of Crowe type IV hip dysplasia with the Wagner cone femoral stem combined with transverse subtrochanteric shortening osteotomy and augmenting the osteotomy site using the intercalary segment as a strut autograft.

METHODS

One hundred twenty-seven hips of 91 patients diagnosed with Crowe type IV hip dysplasia and treated with total hip arthroplasty using the Wagner cone stem combined with transverse subtrochanteric shortening osteotomy were retrospectively evaluated by clinical and radiographic outcomes as well as complications.

RESULTS

The mean follow-up was 8.4 years. The Harris Hip Score and the Western Ontario and McMaster University Osteoarthritis Index scores were significantly improved postoperatively (P = .000). Intraoperative femoral cracks were observed in 70 hips (55.1%) and all femurs healed smoothly. Femoral cracks did not have a significant effect on clinical outcomes, except for heterotopic ossifications (P = .032). The probability of 10-year survivorship of the components free of revision for any reasons as end point was 94.5%; when only the femoral components were considered the survivorship was of 96.9%.

CONCLUSION

Transverse subtrochanteric shortening and augmenting the osteotomy site using the intercalary segment of bone resected from the shortened femur with the Wagner cone stem is an effective and reliable technique in the management of total hip arthroplasty in Crowe type IV hip dysplasia. Stable and firm placing of the femoral component which leads to an increased frequency of intraoperative femoral cracks does not have an unfavorable effect on clinical and radiological outcomes.

Effects of additional neck cut of the femur on the range of motion in total hip arthroplasty for hip dislocation: a computer simulation study

BACKGROUND

Subtrochanteric shortening osteotomy (SSO) is commonly performed in total hip arthroplasty (THA) for high hip dislocation. However, this procedure is technically difficult and includes complications. Additional neck cut (ANC) of the femur is a procedure that involves femoral shortening by possibly eliminating the need for SSO in THA for high hip dislocation. Herein, we evaluated the effect and the depth limit of ANC of the femur on the range of motion (ROM) in THA for high hip dislocation.

METHODS

ROM was measured in 26 patients with high hip dislocation using computer software. The stem was deeply positioned at 5-mm intervals from 0 mm to 30 mm (7 groups). The ROM before impingement was measured during flexion, internal rotation (IR) at 90° flexion, external rotation (ER) and abduction. Receiver operator coefficient (ROC) curves for abduction were generated. The cut-off value of ANC where the required ROM was achieved was also determined.

RESULTS

Deeper ANCs increased the ROM values during flexion and IR, but they decreased the ROM values during ER and abduction. The ROM values during ER were also limited in 0-mm ANCs. According to the result of the ROC curve for abduction, 15 mm was considered as the permissible range of ANC.

CONCLUSIONS

In THA for high hip dislocation additional neck cut should be taken into consideration for hips requiring less than 15-mm shortening. For more extended corrections a subtrochanteric shortening osteotomy should be performed.

[A comparative study of three different fixation methods after subtrochanteric shortening osteotomy in total hip arthroplasty for Crowe type Ⅳ developmental dysplasia of the hip]

Objective

To compare the effectiveness of three different fixation methods after subtrochanteric shortening osteotomy (SSO) in total hip arthroplasty (THA) for Crowe type Ⅳ developmental dysplasia of the hip (DDH).

Methods

A clinical data of 63 patients (78 hips) with Crowe type Ⅳ DDH, who underwent THA with SSO between November 2014 and May 2019, was retrospectively analyzed. Among them, 18 patients (20 hips) obtained stability by intramedullary pressure provided by the S-ROM modular prostheses (group A); 22 patients (30 hips) underwent prophylactic binding by stainless steel wire after osteotomy and before stem implantation (group B); 23 patients (28 hips) were fixed with autogenous cortical strut grafts and stainless steel wire or cables (group C). There was no significant difference in gender, age, body mass index, affected limb side, and preoperative Harris score between groups ( P>0.05). The operation time, complications, imaging results, hip functional score of the three groups were recorded and compared.

Results

There was no significant difference in the operation time between groups ( P>0.05). All incisions healed by first intention. All patients were followed up, and the follow-up time was 2.5-4.0 years (mean, 3.1 years) in group A, 1.5-5.5 years (mean, 3.2 years) in group B, and 1.0-5.0 years (mean, 1.6 years) in group C. There was no significant difference in Harris score or Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score between groups at 4 and 12 months after operation ( P>0.05). X-ray films showed that there was no significant difference in osteotomy healing rate at 4, 8, and 12 months after operation and the osteotomy healing time between groups ( P>0.05). There was no complications such as joint dislocation, prosthesis loosening, prosthetic joint infection, or heterotopic ossification during follow-up, except for the distal femoral fracture of 1 hip during operation in group B.

Conclusion

In THA for patients with Crowe type Ⅳ DDH, the stainless steel wire binding alone and autogenous cortical strut grafts combined with stainless steel wire or cable binding can not significantly promote the osteotomy healing compared with femoral prosthesis intramedullary compression fixation. For patients with nonmatched medullary cavity after SSO, it is recommended to apply autogenous cortical strut grafts with wire or cables for additional fixation.

[Long-term effectiveness of total hip arthroplasty for Crowe type developmental dysplasia of the hip]

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.

Long-Term Clinical Outcomes and Survivorship of Total Hip Arthroplasty for Pyogenic Arthritis: A Retrospective Cohort Study of 168 Hips

Objective

The aim of the present study was to evaluate the 10‐year outcomes of cementless total hip arthroplasty (THA) in adult patients with the late sequelae of septic arthritis of the hip.

Methods

We followed 166 consecutive patients (168 hips) who underwent cementless THA between March 2001 and December 2011. There were 79 men and 87 women, with a mean age of 50.4 years (range 21–76 years) at the time of index THA, all of whom had hip osteoarthritis secondary to hip pyogenic infection. The average duration of follow up was 10.6 years (range 6.9–17.2 years). Preoperative and postoperative clinical ratings were evaluated, including the hip dysfunction and osteoarthritis outcome score (HOOS), the Harris hip score (HHS), range of motion, a 100‐point visual analog scale for hip pain, and the severity of limp and limb length discrepancy (LLD). The anteroposterior and lateral radiographs of the hip and full‐length view of the lower extremities were obtained to assess the position of the components, radiolucent lines, osteolysis, loosening of components, and heterotopic ossification. The intraoperative and postoperative complications were also recorded.

Results

The mean HSS and hip pain score were 44.2 points (range 29–66 points) and 42.5 points (range 32–64 points), respectively, before the index surgery and significantly improved to 88.1 points (range 78–96 points) and 15.1 points (range 10–26 points), respectively, at final follow‐up examination. The HOOS and range of motion also improved significantly. The mean limb length discrepancy was reduced from 2.6 to 0.8 cm. The limp at last follow‐up examination was moderate in 3 cases because of hip osteoarthritis in the other limb, slight in 26, and absent in 137. A radiolucent line was observed in 12 hips (7.1%) around the acetabular or femoral components. A progressive radiolucent line around the undersized femoral stem in all zones was seen in 1 hip, resulting in aseptic loosening and breakage of the femoral component. There were 8 cases of intraoperative fracture, 7 cases of dislocation, and 7 cases of transient nerve palsy. Recurrence of infection occurred in 2 hips. Revision surgery was conducted in 2 hips because of isolated loosening of the acetabular cup and the femoral stem, respectively. Kaplan–Meier survival was 97% at 10 years, with revision for any reason with any component as an end‐point.

Conclusion

Improved surgical techniques and development of components with various sizes provided favorable results for cementless THA conducted for late sequelae of sepsis in these young and active patients. Although the incidence of complications was relatively high, the complications were treated successfully.

Cementless total hip arthroplasty for three different degrees of hip involved secondary to ankylosing spondylitis: an analysis of 195 hips

Background

Hip involved secondary to ankylosis spondylitis (AS) had a huge influence on hip function. Cementless total hip arthroplasty (THA) can improve hip function. However, no previous study compared the outcomes of THA for AS patients with three different degrees of hip involvement.

Methods

The 195 hips were retrospectively analyzed and divided into non-ankylosed group (group A, 94 hips), fibrous ankylosed group (group B, 49 hips), and bony ankylosed group (group C, 52 hips). postoperative range of motion (ROM), harris hip scores (HHS), the short-form 12 health survey (SF-12), length of stay (LOS), cost, radiological assessments, and complications were compared.

Results

The follow-up time was (79.4 ± 29.5) months for group A, (80.6 ± 28.9) months for group B, and (79.1 ± 28.9) months for group C (P = 0.966). Group A had the best postoperative hip ROM (P < 0.001), while group A and B can realize better HHS than group C (P < 0.001). The three groups had similar SF-12 postoperatively. For group A, LOS and cost for unilateral procedure were the least than that for group B and C (P = 0.003 and P = 0.001). Similar radiological assessments were achieved for three groups. 1 hip in group A encountered delay union of wound. 1 hip in group C encountered delay union of wound and dislocation and another patient encountered femoral fracture intraoperatively. 12 hips (12.8%) in group A, 6 hips (12.2%) in group B, and 6 hips (11.5%) in group C encountered asymptomatic heterotopic ossification (P = 0.977).

Conclusion

For AS patients with hip involvement, THA can improve hip ROM and function. THA for the non-ankylosed hip can realize the better hip function and postoperative ROM than ankylosed hip.

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.

Staged reconstruction of unilateral neglected hip dislocation through total hip arthroplasty and subsequent intramedullary femoral lengthening

Background and purpose

Total hip arthroplasty (THA) is a successful approach to treat unilateral symptomatic neglected hip dislocation (NHD). However, the extensive leg length discrepancy (LLD) can hereby only be partially corrected. In case of residual LLD of more than 2 cm, subsequent femoral lengthening can be considered.

Patients/material/methods

Retrospective analysis of clinical data and radiographs of five patients (age 38.1 (28–51) years) with unilateral NHD who underwent THA with (n  = 3) or without (n = 2) subtrochanteric shortening osteotomy (SSO) and secondary intramedullary femoral lengthening through a retrograde magnetically-driven lengthening nail (follow-up 18.4 (15–27) months).

Results

LLD was 51.0 (45–60) mm before and 37.0 (30–45) mm after THA. Delayed bone union at one SSO site healed after revision with autologous bone grafting and plate fixation. Subsequent lengthening led to leg length equalisation in all patients. Complete consolidation was documented in all lengthened segments.

Conclusion

Staged reconstruction via THA and secondary femoral lengthening can successfully be used to reconstruct the hip joint and equalise LLD. The specific anatomical conditions have to be taken into consideration when planning treatment, and patients ought to be closely monitored.

Comparison of mid-term clinical results between cementless and cemented femoral stems in total hip arthroplasty with femoral shortening osteotomy for Crowe type IV hips

INTRODUCTION

This report is the first study to compare the clinical outcomes between cementless and cemented femoral prostheses in total hip arthroplasty (THA) with subtrochanteric femoral shortening osteotomy for Crowe type IV hips.

MATERIALS AND METHODS

We identified 26 hips in 20 patients who had undergone cemented (n = 13) or cementless (n = 13) THA with subtrochanteric femoral shortening osteotomy for Crowe type IV hips with a minimum follow-up period of 2 years. The mean follow-up period was 60.8 ± 33.9 months (24-120 months). We compared radiological findings, postoperative clinical recoveries, postoperative complications, and implant survival rates.

RESULTS

In both groups, there were no cases of aseptic loosening for the acetabular and femoral implant. In terms of bone union at the osteotomy site, the mean duration was significantly longer in the cemented group (9.8 ± 4.2 months) than in the cementless group (5.0 ± 1.9 months). The clinical hip score in gait and pain at 3 months postoperatively was significantly higher in the cemented group than in the cementless group, while there were no significant changes at other timepoints between two groups. The number of postoperative complications was not significantly different between the two groups. The implant survival rate was 92% in the cementless group and 100% in the cemented group at 5 years postoperatively (P = 0.31).

CONCLUSIONS

The cemented femoral prosthesis is superior to the cementless femoral prosthesis for early clinical recovery, while the duration required to achieve bone union at the osteotomy site is longer in the cemented femoral prostheses. It is possible for surgeons to perform successful hip reconstructions, regardless of the fixation method used for THA with shortening femoral osteotomy.

Modular prosthesis fracture in a patient with developmental dysplasia of the hip: a case report and literature review

Background

Modular prosthesis fracture, especially distal femoral fracture, is a rare complication of total hip arthroplasty (THA). However, it is catastrophic, and may have a serious impact on the patients. A distal femoral prosthesis fracture in a patient with developmental dysplasia of the hip (DDH) with nonunion at the subtrochanteric osteotomy site has not yet been reported in any literature. This report presents the first such case, with a purpose of analyzing the causes of modular prosthesis fractures and nonunion of the osteotomy area, so as to provide orthopedic surgeons with experience and lessons.

Case presentation

We report the case of a 52-year-old woman with the distal femoral prosthesis fracture after THA and subtrochanteric osteotomy for Crowe type IV DDH. The patient had severe pain in the left thigh and her activities were limited. Plain radiographs revealed fracture of the left distal femoral prosthesis and nonunion in the subtrochanteric osteotomy region of the left femur. After a revision of the THA, the patient’s symptoms were resolved.

Conclusions

A prosthesis fracture combined with nonunion at the subtrochanteric osteotomy site is a rare complication. Modular THA combined with a subtrochanteric osteotomy in the treatment of Crowe type IV DDH should reduce the damage to blood supply and avoid further nonunion of the osteotomy area, which may otherwise lead to modular prosthesis fractures. A detailed preoperative plan and suitable rehabilitation program may help minimize the occurrence of subtrochanteric osteotomy nonunion and reduce complications, including femoral prosthesis fractures, in patients with DDH.

Changes in Distribution of Lower Limb Alignment After Total Hip Arthroplasty for Crowe IV Developmental Dysplasia of the Hip

Purpose

The purpose of this study was to evaluate the distribution of lower limb alignment in Crowe IV developmental dysplasia of the hip (DDH) before and after total hip arthroplasty (THA).

Patients and Methods

We retrospectively included 64 Crowe IV DDH patients (87 hips) who underwent THA between February 2010 and May 2019. Radiographic parameters were measured on full limb length standing anteroposterior radiographs, including hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), anatomical lateral distal femoral angle (aLDFA), and anatomical tibiofemoral angle (aTFA).

Results

HKA improved from 176.54°±3.52° preoperatively to 179.45°±4.31° at the last followup (P<0.001). According to the preoperative HKA, 40 hips were defined as knee valgus alignment. The majority of them were characteristic of a valgus mLDFA and a valgus or neutral mMPTA (35%, 47.5%). After THA, there were still 22 hips defined as knee valgus alignment. More than 50% of them were characteristic of a valgus mLDFA and a neutral mMPTA. Five hips (22.7%) revealed valgus alignment in both mLDFA and mMPTA. Twenty-one hips (24.1%) remained knee valgus alignment before and after surgery. One hip, defined as neutral alignment, preoperatively turned into valgus alignment after surgery.

Conclusion

Both preoperative and postoperative sources of valgus alignment were mainly from the femoral side among Crowe IV DDH patients. THA mainly played a positive role in the reconstruction of lower limb alignment in these patients.

Survival Analysis of Total Hip Arthroplasty for High Hip Dislocation Secondary to Developmental Dysplasia or Septic Arthritis of the Hip

BACKGROUND

This retrospective study was conducted to know clinical and radiographic outcomes, complication rate, and survival of THA in patients with high hip dislocation secondary to developmental dysplasia(DDH) or septic arthritis of the hip(SSH).

METHODS

Between March 2005 and September 2014, there were consecutive series of 53 THAs in patients with a highly dislocated hip secondary to DDH or SSH. Of these, 48 hips (DDH 24 and SSH 24) were reviewed at a mean follow-up of 7.9 years(range, 5.0-14.3 years). The mean age at the time of THA was 39.1 years(range, 18.0-59.0 years).

RESULTS

Intraoperative blood loss, total drainage and blood transfusion amounts, and mean time to greater trochanter union were significantly lower in the DDH group than in the SSH group (P = .001, P = .039 and P = .014, and P = .015, respectively). No significant difference in Kaplan-Meier survivorship was observed between groups (log-rank, P = .343). The survival rates with an endpoint of cup aseptic loosening in cases with a cemented cup at 7.9 and 10 years (68.1% and 60.5%, respectively) were significantly lower than those in cementless cup cases (100%) at the same checkpoints (P = .019)..

CONCLUSION

We found similar clinical outcomes between the DDH and SSH groups. However, due to poor bone quality and a lack of containment, cementless acetabular cups could not be performed in more than 50% of patients. Our experience shows that revision cementless fixation cup was possible due to reconstitution of the acetabulum in cases with failed cemented fixation.

Low Reinfection Rates But a High Rate of Complications in THA for Infection Sequelae in Childhood: A Systematic Review

BACKGROUND

Childhood hip infections can result in serious sequelae during adulthood, including persistent pain, functional limitations, and premature THA. When THA is performed in patients who had hip joint infections during childhood, surgeons surmise these arthroplasties are at an increased risk of complications and incomplete recovery. However, the degree to which this is true is not well characterized and has varied across a large number of small, retrospective studies.

QUESTIONS/PURPOSES

(1) What proportion of THAs performed in patients who had pediatric septic arthritis result in periprosthetic joint infection? (2) What are the Harris hip scores associated with these reconstructions? (3) What proportion of these patients develop complications after THA? (4) What proportion of patients undergo revision after these THAs?

METHODS

For this systematic review, we searched the MEDLINE (PubMed), Scopus, and CINAHL (EbscoHost) electronic databases. We evaluated studies published in English between 1980 and 2020 that had a minimum of 10 patients (with a minimum of 2 years of follow-up) in whom sequelae of septic arthritis of the hip were treated with single-stage THA. We also evaluated studies reporting clinical outcomes by means of the Harris hip score, along with a radiographic assessment of the prosthesis. Updates of previous studies using the same database, case reports, surgical technique reports, systematic reviews, and expert opinions were excluded. No restrictions were applied regarding study design and loss to follow-up. A total of 430 studies were identified through the initial search, and 11 studies were included after applying the inclusion and exclusion criteria. All but two studies, which included a historical control group, were retrospective case series. A total of 691 patients with a mean age of 45 years were involved. A total of 599 patients underwent cementless THAs, 84 patients underwent hybrid THA (cemented stems), and the remaining eight patients received a cemented THA. A total of 287 additional procedures were performed on the acetabulum, including autografting, allografting, and medial wall osteotomies; in three hips, tantalum augments were used. Three hundred thirty-five additional procedures were performed on the femora, including 223 shortening osteotomies and 112 greater trochanter osteotomies. The mean follow-up duration ranged from 5.5 to 15.2 years (minimum follow-up range 2-13 years). To assess the quality of the studies, we used the Methodological Index for Non-randomized Studies and the Assessment of Quality in Lower-limb Arthroplasty, for which a higher score represents a better study quality. The mean Methodological Index for Non-randomized Studies score for case series was 9 of 16 (range 6-12), and 19 and 18 of 24 for the two comparative studies. The mean reporting quality of the Assessment of Quality in Lower Limb Arthroplasty score was 6 of 8 (range 3-8).

RESULTS

Because of loss to follow-up, which was not consistently reported in the source studies, we caution the reader that the estimates provided here likely underestimate the risks of adverse events and overestimate the mean hip scores. The pooled proportion of patients in whom infections developed was 1% (seven of 691 THAs). Considering only studies published in the past 10 years, the proportion was 0.7% (two of 276 THAs). The Harris hip score increased from a mean of 52 ± 6 points before THA to a mean of 88 ± 2 points after THA. The pooled proportion of complications, including sciatic nerve palsy, femoral nerve palsy, intraoperative periprosthetic fracture, deep venous thrombosis, and dislocation, was 11% (76 complications among 691 THAs). The pooled proportion of patients who underwent revision was 8% (53 revisions of any components for any reason among 691 THAs) at a mean follow-up interval of 9.1 ± 3 years.

CONCLUSION

In THAs for sequelae of childhood septic arthritis, reinfections were uncommon, whereas generally, infection rates were slightly higher than those reported for conventional primary THAs. However, the duration of follow-up might have been insufficient to identify all patients in whom infections later developed, and the available data were not adequate to precisely detect the minimum quiescent period to avoid reinfections. Moreover, the studies in this systematic review were retrospective, and selection bias, transfer bias, and assessment bias likely influenced our findings. The general effect of these biases is to cause an underestimation of the harms of the intervention. Complications, especially intraoperative fracture and nerve palsy, were common in patients with the most-severe infections. Further data on this topic are needed, ideally from multicenter or registry studies with even longer follow-up durations.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Clinical evaluation of direct anterior approach total hip arthroplasty for severe developmental dysplasia of the hip

It is challenging to treat developmental dysplasia of the hip (DDH) classified Crowe III-IV using direct anterior approach (DAA) total hip arthroplasty (THA), and very little is known on its outcome. This study aimed to investigate the clinical result in this defined disorder with DAA versus posterolateral approach. Twenty-three consecutive hips with Crowe III-IV DDH who underwent DAA were retrospectively evaluated from 2016 through 2018. Outcomes were primarily assessed by HHS, WOMAC, and SF-12 physical scales. The second evaluations included leg length discrepancy, hip muscle strength, radiographic review, complications, and limp recovery. Results were compared to a control cohort of 50 hips underwent posterolateral THA concurrently within the observational period. At last follow-up (DAA 28.5 months; PLA 39.0 months), the mean increase of the HHS for DAA was 48.2 and 30.3 for PLA (p = 0.003). The improvement in WOMAC score in DAA cohort was 15.89 higher that of the PLA cohort after adjusting preoperative difference [R2 = 0.532, P = 0.000, 95% CI (10.037, 21.735)]. DAA had more rapid recovery of hip abductor strength at 1-month (p = 0.03) and hip flexor strength at 3 months (p = 0.007) compared to PLA. No significant differences were found in the radiographic analysis with the exception of increased acetabular anteversion in the DAA cohort (p = 0.036). Satisfactory improvement in limp, indicated by the percentage of limp graded as none and mild to the total, was much higher in DAA cohort (97.6%), compared to that of PLA cohort (90.0%, p = 0.032). DAA for high-dislocated dysplasia demonstrate a significant improvement in clinical result comparable to posterolateral approach. Improved clinical outcome in terms of increased HHS and WOMAC scores, rapid recovery of hip abductor and flexor strength, and enhanced limp recovery without an increased risk in complications, could be acquired when the surgeons were specialized in this approach.

Functional and radiographical results of asymmetrically reconstructed total hip arthroplasty in patients with bilateral dysplastic arthritic hips with one hip Crowe II-III and the other Crowe IV: a retrospective cohort study

Background

The study aimed to evaluate the functional and radiographical results of asymmetrically reconstructed total hip arthroplasty in patients with bilateral dysplastic arthritic hips with one hip Crowe II–III and the other hip Crowe IV.

Materials and methods

From April 2006 to April 2019, we evaluated 23 patients who had a reconstruction of one Crowe II–III hip with high hip center (HHC) and the other Crowe IV hip at the anatomical position (H group). The radiographic and clinical outcomes were compared with those of a control group of 19 patients with bilateral dysplasia who had one Crowe IV hip and the contralateral hip both reconstructed in the anatomical position (A group). Medical records and radiographs were reviewed, and a complete follow-up was conducted for all patients.

Results

The mean vertical center of rotation (V-COR) and horizontal center of rotation (H-COR) in the H group were 30.6 ± 5.8 mm and 30.0 ± 5.5 mm, respectively. In the A group, the corresponding values were 14.0 ± 4.3 mm and 23.0 ± 2.3 mm, respectively. A significant difference was found in terms of V-COR and H-COR between the two groups, and no significant difference was shown regarding the cup inclination, abductor lever arm (ALA), ALA ratio, and leg length discrepancy (LLD). Three patients of the H group and four patients of the A group exhibited LLD > 10 mm. All seven patients who had LLD > 10 mm underwent the shortening subtrochanteric osteotomy (SSTO) of the Crowe IV hip. Subgroup analysis based on the presence and absence of SSTO showed that the LLD of the SSTO group was greater than that of the non-SSTO group in both groups, but the difference was only statistically significant in the A group. At the last follow-up, the mean Harris Hip Scores significantly improved in the two groups, and there was no revision during the follow-up period. In the H group, four patients presented with a slight limp and three patients with a moderate limp, while it was six patients and one patient in the A group, respectively.

Conclusions

Asymmetrical reconstruction in patients with bilateral dysplastic arthritic hips with one hip Crowe II–III and the other Crowe IV is acceptable and comparable when compared with bilateral anatomical reconstruction.

Level of evidence

III, retrospective observational study.

Trial registration Chinese Clinical Trail Registry. ChiCTR2000033848

Total hip arthroplasty combined with subtrochanteric shortening osteotomy for Crowe type IV hip dysplasia in dwarfism: a case report

Dwarfism is a condition of extreme short stature. Total hip arthroplasty (THA) in patients with dwarfism is a very demanding procedure due to their specific joint deformity and small bone size, which increases the technical difficulty of the THA procedure in such patients with hip dysplasia. This current case report describes a 29-year-old female patient that was admitted due to shortening of the right lower limb, as compared with the contralateral side, which had been present for 18 years. She also complained of pain in the right hip that had been present for 2 months. The hip pain was aggravated by physical exertion, but relieved by rest. She had pituitary dwarfism without mental retardation or delayed sexual development and Crowe type IV dysplasia of the right hip. A THA combined with femoral shortening osteotomy was undertaken, which resolved the pain symptoms and improved her ability to undertake activities of daily living such as walking without pain. Dwarfism with hip dysplasia is a rare but extremely challenging problem that can be successfully treated with THA combined with femoral shortening osteotomy using an S-ROM stem.

Long-Term Outcomes of Total Hip Arthroplasty With Transverse Subtrochanteric Shortening Osteotomy and Modular Stem in Crowe IV Developmental Dysplasia

BACKGROUND

The reconstruction of high dislocation related to developmental dysplasia of the hip (DDH) remains challenging for joint surgeons. The aim of this study is to evaluate the rate of union, the revision rate, functional scores, and complications in patients with Crowe IV DDH treated with total hip arthroplasty, transverse subtrochanteric shortening osteotomy, and modular stem in an average 10-year follow-up.

METHODS

Twenty-eight patients (33 hips) with Crowe IV DDH who were operated on between 2008 and 2013 were followed. All patients underwent uncemented total hip arthroplasty with transverse subtrochanteric shortening osteotomy and anatomical acetabular cup implantation. The mean age was 36.6 years, and the mean follow-up period was 121 months. Clinical and radiological outcomes were evaluated.

RESULTS

The mean Harris Hip Score significantly improved from 47.0 preoperatively to 89.6 postoperatively. The mean limb length discrepancy was significantly reduced from 3.8 to 0.8 cm. The mean osteotomy union time was 6.8 months. At the mean follow-up of 121 months, there were 3 cases of postoperative dislocation, 2 cases of intraoperative fracture, and 1 case of posterior tibial venous thrombosis. No revision occurred, and no signs of component loosening or migration were observed at the last follow-up.

CONCLUSION

Crowe IV DDH patients treated with transverse subtrochanteric shortening osteotomy, modular stem, and anatomic acetabular component insertion can have satisfactory and reliable 10-year clinical outcomes.

Mid-term results of total hip arthroplasty with modified trochanteric osteotomy in Crowe type IV developmental dysplasia of the hip

Background

This study aimed to explore mid-term clinical results of cementless total hip arthroplasty (THA) with modified trochanteric osteotomy in Crowe type IV developmental dysplasia of the hip (DDH).

Methods

Thirteen patients (13 hips) with Crowe type IV DDH who underwent THA with modified trochanteric osteotomy between May 2013 and October 2015 were retrospectively analyzed. The mean follow-up duration was 5.2 years (range, 4.9–6.1 years).

Results

The mean Harris Hip Score (HHS) significantly (p < 0.05) improved from 30.7 (range, 22–38) to 87.5 (range, 83–93). The mean leg length discrepancy (LLD) was 53.4 mm (range, 42.1–68.5 mm) preoperatively. The final LLD was 5.6 mm (range, 2.4–9.1 mm; p < 0.05). The mean leg length after surgery was 47.4 mm (range, 33.6–67.2 mm) and the femur shortening distance was 43.8 mm (range, 31.2–53.4 mm). The average duration of bone union for the greater trochanter (GT) was 2.5 months (range, 1.5–3.6 months). There was no infection, GT non-union, or loosening (septic or aseptic) of the stem or cup in any case.

Conclusions

THA with modified trochanteric osteotomy with a cementless cup is an effective treatment for Crowe type IV DDH. It can rebuild complex biomechanics and biology of hip dysplasia without increasing complications.

Radiographic factors to predict operation time of direct anterior total hip arthroplasty for dysplastic hips

BACKGROUND

This study aimed to identify radiographic factors that could predict surgical difficulty in direct anterior total hip arthroplasty (THA) for dysplastic hips.

PATIENTS AND METHODS

The clinical records of 160 patients (204 hips) who underwent primary THA for the treatment of developmental dysplasia of the hip were retrospectively investigated. All THAs were performed through a direct anterior approach by a single surgeon. A multiple regression analysis was developed to identify the independent predictor of operation time, including variables such as age, sex, height, body mass index (BMI), the use of bone cement, previous hip surgery, and radiographic references, including the pelvic horizontal to vertical ratio, the extent of proximal and horizontal migration of the femoral head, flatness of the femoral head, and the vertical distance between the tips of the greater trochanter and the femoral head.

RESULTS

A multiple regression analysis revealed that as radiographic factors, proximal migration of the femoral head, and lower position of the femoral head related to the greater trochanter were significantly associated with longer operation time. In addition, our results revealed that younger age, male sex, height, high BMI, cement use, and previous hip surgery were also significantly associated with longer operation time.

CONCLUSIONS

Our findings indicate that proximal migration of the femoral head and high-riding greater trochanter are isolated radiographic predictors of the longer operation time of direct anterior THA for dysplastic hips.