Arthroscopy Confers Favorable Clinical Outcomes in Asian Patients with Borderline Developmental Dysplasia of the Hip

Objective

Hip arthroscopy has recently appeared as a successful therapy in treating borderline developmental dysplasia of the hip (BDDH). This study aimed to describe the minimal 2-year follow-up after hip arthroscopy for patients with BDDH in the Asian population and use the combination of lateral center edge angle (LCEA) and alpha angles to detect the appearance of impingement in the BDDH population.

Methods

This retrospective investigation was conducted utilizing information from arthroscopically treated BDDH patients in 2018 and 2019. The following patient-reported outcomes were reported: modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living, International Hip Outcome Tool 12-component form, and Visual Analog Scale. We also considered the clinical data regarding radiological measurements, intraoperative findings, interventions, complications, and subsequent surgical revisions, in the analysis of combination angles in detecting the occurrence of impingement. Patients with asymptomatic contralateral hips from traumatic hip injury (pelvic fracture) served as the control group. A 2:1 propensity score matching was based on age, sex, and BMI. A receiver operating characteristic curve (ROC) was used to identify the thresholds of combination angles and their accuracies.

Results

A total of 77 hips met the inclusion and exclusion requirements. After the follow-up period, most patients showed a considerable improvement in patient-reported outcomes compared to their preoperative values (P < 0.001 for all). The overall rate of complications was 5.2%, whereas the rate of revisions was 3.9%. Increasing preoperative alpha angle age was significantly positively correlated with improving patient-reported outcomes. The combined angle cut-off was determined to be 80.5° (AUC, 0.858; 95% CI: 0.757–0.938; sensitivity (SE), 98.1%; specificity (SP), 74.1%; P < 0.001) for the occurrence of impingement in BDDH population.

Conclusion

Good patient-reported outcomes and low revision rates can be expected in the BDDH population with careful selection of patients in Asian populations. A combination angle >80.5° could be a reliable predictive factor of impingement in BDDH populations.     

Arthroscopic Treatment of Labral Tears in Patients with Borderline Developmental Dysplasia of the Hip: A Retrospective Study with Mean 5.8 Years Follow‐Up

ObjectiveTo retrospectively assess the mid‐term clinical and radiological results of hip arthroscopic treatment of labral tears in patients with borderline developmental dysplasia of the hip (BDDH).MethodsFrom January 2010 and December 2019, data were retrospectively reviewed for all patients who underwent arthroscopic surgery of the hip for the treatment of intra‐articular abnormalities. Only the Patients who had borderline developmental dysplasia (BDDH) were included. All operations were performed by two senior surgeons, the arthroscopic treatment including labral repair, labral debridement, minimal acetabuloplasty, femoroplasty and capsular closure. The evaluation consisted of pain evaluation (visual analog scale [VAS]), the modified Harris hip score (MHHS), range of motion, the radiological evaluation of plain film and MRI analysis of the hip joint. The plain film evaluation included anteroposterior views of the pelvis to assess lateral center‐edge angle (LCEA) and acetabular inclination (AI), frog‐leg lateral views of the hip to assess α angle.ResultsThere were 34 patients (36 hips) ultimately enrolled in this study. The follow‐up duration of the patients were minimal 2 years (average, 69.2 months) postoperatively. The patient group included seven men and 27 women, the mean age at the time of surgery was 30.9 years. The mean BMI was 22.3 kg/m². From the pre‐operative status to the final follow‐up visit, mean mHHS score increased from 64.5 to 92.7, mean VAS score decreased from 6.8 to 1.3. All scores exhibited statistically significant differences (P < 0.001). The mean LCEA decreased from 22.9° to 22.7°, the mean AI decreased from 7.7° to 7.6°. Which all showed no significant differences compared with the final follow‐up to the pre‐operative status (P > 0.05). However, the mean α angle was significantly decreased from 48.3° to 40.1° (P < 0.001). We encountered no significant complications such as infection, deep venous thrombosis, fluid extravasation, or permanent nerve injury. One patient (2.94%) underwent revision periacetabular osteotomies (PAO) because of subluxation of the hip joint with permanent pain after 6 months failed conservative treatment.ConclusionArthroscopic treatment of labral tears in patients with BDDH may provide safe and durable favorable results at midterm follow‐up. The best outcome could be expected in patients with labral repair and closure of the capsule with strict patient selection criteria.     

Outcomes in Patients with Global Pincer Versus Focal Pincer Femoroacetabular Impingement Treated with Hip Arthroscopy: A Retrospective Study with a Minimum 2‐Year Follow‐Up

ObjectiveGlobal pincer is a relatively rare form of pincer deformity and is typically associated with technical challenges during surgery. So far, controversy remains whether patients with global pincer have equivalent surgical outcomes compared to patients with focal pincer. This study compares the clinical outcomes of arthroscopic treatment between patients with global pincer femoroacetabular impingement (FAI) and focal pincer FAI in the Chinese population.MethodsData were retrospectively collected from patients with global and focal pincer FAI who underwent hip arthroscopy with a minimum two‐year follow‐up between April 2016 and December 2018. Radiographic measurements, arthroscopic procedures, preoperative and postoperative patient‐reported outcomes (PROs) including modified Harris hip score (mHHS), hip outcome score‐activities of daily living (HOS‐ADL), international hip outcome tool–12 (iHOT‐12), and visual analogue scale (VAS) scores, rates of revision surgery and conversion to total hip arthroplasty (THA) were recorded. Achievement of minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) was compared for the VAS, mHHS, HOS‐ADL, and iHOT‐12 scores between groups.ResultsThe total of 33 and 167 patients were included in the global and focal group, respectively. There were no intergroup differences in age, gender, body mass index or follow‐up times. Lateral center‐edge angle (LCEA) was reduced in both groups postoperatively. Both groups demonstrated significant improvements in PROs compared with preoperative levels at the final follow‐up. The preoperative scores showed significant differences in terms of mHHS (60.34 vs 62.90, P = 0.031) and HOS‐ADL (61.45 vs 64.74, P = 0.022) scores between two groups, and the improvement of HOS‐ADL score was significantly higher in global group (P = 0.027). However, the postoperative scores, including VAS, mHHS, HOS‐ADL, and iHOT‐12 scores, showed no significant differences between two groups. And there were no significant differences in the rate of meeting the PASS and MCID between groups. One (3.0%) in the global group and six (3.6%) patients in the focal group underwent revision arthroscopy respectively, with no significant difference (P = 0.876). There were no conversions to THA in both groups.ConclusionsArthroscopic management of global pincer FAI can achieve excellent functional scores at minimum 2‐year follow‐up. The outcomes were similar to focal pincer FAI patients with a low rate of secondary procedure.     

Restoring Rotation Center in Total Hip Arthroplasty for Developmental Dysplasia of the Hip with the Assistance of Three Dimensional Printing Technology: A Pilot Study

ObjectiveTo develop a new method to restore hip rotation center exactly and rapidly in total hip arthroplasty (THA) with the assistance of three dimensional (3D) printing technology and evaluate its clinical and radiological outcomes.MethodsFrom March 2014 to July 2018, a total of 17 patients (five hips of four men and 16 hips of 13 women) with end‐stage osteoarthritis secondary to developmental dysplasia of the hip who underwent THA were analyzed and followed up retrospectively. The average age is 58.00 ± 8.12 years (range from 45 to 71 years). Simulated operations were performed on 3D printed hip models for preoperative planning. The morphology of Harris fossa and acetabular notches were recognized and restored to locate the acetabular center. The size of bone defect was measured by the bone wax method. The agreement on the size of acetabular cup and bone defect between simulated operations and actual operations were analyzed. Harris Hip Score (HHS) was used to evaluate the recovery of hip joint function. The vertical distance and horizontal distance of the rotation center on the pelvis plain radiograph were measured, which were used to assess the efficacy of restoring hip rotation center and acetabular cup migration.ResultsThe mean sizes of bone defect in simulated operations and THA were 4.58 ± 2.47 cm² and 4.55 ± 2.57 cm² respectively. There was no significant difference statistically between the sizes of bone defect in simulated operations and the actual sizes of bone defect in THA (t = 0.03, P = 0.97). The sizes of the acetabular cup of simulated operations on 3D print models showed a high rate of coincidence with the actual sizes in the operations (ICC = 0.93). All 17 patients were available for clinical and radiological follow‐up. The average follow‐up time was 18.35 ± 6.86 months (range, 12–36 months. The average HHS of the patients was improved from (38.33 ± 6.07) preoperatively to the last follow‐up (88.61 ± 3.44) postoperatively. The mean vertical and horizontal distances of hip rotation center on the pelvic radiographs were restored to 15.12 ± 1.25 mm and 32.49 ± 2.83 mm respectively. No case presented dislocation or radiological signs of loosening until last follow‐up.ConclusionsThe application of 3D printing technology facilitates orthopedists to recognize the morphology of Harris fossa and acetabular notches, locate the acetabular center and restore the hip rotation center rapidly and accurately.     

Total Hip Arthroplasty or Arthroscopy for Pigmented Villonodular Synovitis of the Hip: A Retrospective Study with 3-Year Follow-Up at Minimum

Objective

Pigment Villonodular synovitis of the hip, a rare pain proliferation of the synovium, was treated successfully with total hip arthroplasty and arthroscopy. Most recent results come from small case series with no study comparing arthroscopy and arthroplasty. In this study, we aimed to show and compare the clinical outcomes of arthroscopy and total hip arthroplasty (THA) in pigment Villonodular synovitis of the hip.

Methods

This was a retrospective clinical trial with data from patients with pigment Villonodular synovitis of the hip between 2010 and 2019. The study included 17 patients in the THA group, and 20 patients in the arthroscopy group. The clinical outcomes were evaluated at 3, 6, and 12 months, at 1 and 2 years, and every 5 years afterward. The clinical efficacy was measured using the Harris hip scores (HHSs) and visual analogue scale (VAS) score.

Results

The mean HHS improved from 45.24 ± 10.36 to 78.94 ± 19.11 in the THA group (t = −6.394, P = 0.000) and 45.30 ± 11.08 to 71.60 ± 19.78 (t = −5.187, P = 0.000) in the arthroscopy group from pre-operation to the final follow-up. There is no significant difference between the two groups (t = 1.051, P = 0.301). The mean VAS improved from 3.65 ± 0.79 to 0.35 ± 0.70 (t = 12.890, P = 0.000) in the THA group and 4.05 ± 0.94 to 1.35 ± 1.79 (t = 5.979, P = 0.001) in the arthroscopy group postoperatively. There is no significant difference between the two groups (t = 1.329, P = 0.193). Recurrence of PVNS was diagnosed in four patients (20%) of the arthroscopy group and they underwent THA after arthroscopy, and the mean interval was 44.25 ± 6.98 months. All patients reached level 5 muscle strength by the final follow-up. All the patients' buckling ranges were over 105 degrees. Their internal and external hip rotation was over 15 degrees. Their hip adduction was over 20 degrees, and abduction over 30 degrees.

Conclusion

Both THA and arthroscopy in the setting of PVNS can improve patients' function and lead to a low rate of local recurrence. By selecting patients well for each approach, one can expect a reasonable result.     

Cost Analysis of Screening Programmes for Developmental Dysplasia of the Hip: A Systematic Review

AimsThe aim of this study was to assess screening costs in developmental dysplasia of the hip (DDH), to provide any clarity on the cost-effectiveness of various hip screening programmes internationally.MethodsA PROSPERO-registered systematic review was performed by examining cost analysis studies of various DDH screening programmes, including those based around clinical examination, selective ultrasound and universal ultrasound. Costs were analysed using narrative synthesis.ResultsThere were 14 studies included in this review. Two studies found that clinical hip screening is advantageous over no screening at all, both in terms of overall cost and favourable outcomes. When considering selective ultrasound imaging versus clinical screening, two studies found it to be more expensive, one found it cheaper and three studies calculated the overall programme costs to be similar. With universal ultrasound, four studies calculated this to be cheaper than clinical or selective ultrasound screening due to a reduced late detection and surgery rate. However, a comparable number of studies concluded that the increased financial costs of universal ultrasound were greater than the reduction in surgical costs. No studies included any long-term data.ConclusionThere is a dearth of information on DDH screening costs, with significant heterogeneity amongst the existing literature. Future research should include the cost analysis of long-term complications of DDH, including the social and psychological impact of early onset arthritis, as well as gender specific ultrasound screening programmes.     

Demographic and Practice Variability Amongst Indian Centres in a Multicentre Prospective Observational Study on Developmental Dysplasia of the Hip

BackgroundSince 2017, five Indian centres have enrolled into the International Hip Dysplasia Registry for prospective collection of data on Developmental Dysplasia of Hip (DDH).AimsTo assess how baseline patient characteristics and initial treatment modalities differ across these five centres.MethodsRegistry data collected over 3 years were analyzed. Children with DDH that had radiograph-based diagnoses were included.ResultsCollectively, there were 234 hips (181 patients), of which 218 had undergone surgery. Overall, median age at presentation was 25.3 months (IQR 16.8–46.0); female/male ratio was 2.6:1 (range 1.46–4.75:1); with 42%, 29%, and 29% unilateral left, bilateral and unilateral right hip dislocations respectively. Most were IHDI grade III and IV dislocations (94%). Closed reduction was performed at all but one centre, at median 15.3 months (IQR 9.6–21.1). Open reduction (OR) as a stand-alone procedure was performed at all centres, at median 20.8 months (IQR 15.4–24.9). Combination of OR with a single osteotomy, femoral (FO) or acetabular (AO), was performed at all centres at median 29.7 months (IQR 22.1–43.5). However, for the same age group, three centres exclusively performed FO, whereas the other two exclusively performed AO. The combination of OR with both FO and AO was used at all centres, at median 53.4 months (IQR 42.1–70.8).ConclusionsThe preliminary findings of this multi-centre study indicate similar patient demographics and diagnoses, but important differences in treatment regimens across the five Indian centres. Comparison of treatment regimens, using the ‘centre’ as a predictive variable, should allow us to identify protocols that give superior outcomes.     

A Comparative Study of Clinical and Radiological Outcomes of Open Reduction Using the Anterior and Medial Approaches for the Management of Developmental Dysplasia of the Hip

BackgroundThe literature is scanty on reports directly comparing the outcomes of anterior open reduction (AOR) and medial open reduction (MOR) in the management of developmental dysplasia of the hip (DDH).Purpose of the StudyTo compare clinical and radiographic outcomes of surgical treatment using either AOR or MOR in children with DDH aged < 24 months and to evaluate the procedure-inherent risks of avascular necrosis of the femoral head (AVN) and need for further corrective surgery (FCS).Methods61 children who underwent surgical treatment for DDH were categorized into two groups: AOR (31 hips of 28 patients) and MOR (39 hips of 33 patients). The mean age was 17 ± 5.85 (range 7–24) months in group AOR and 13 ± 5.31 (range 6–24) months in group MOR. The mean follow-up was 118 ± 41.2 (range 24–192) months and 132 ± 36.7 (range 24–209) months in group AOR and MOR. At the final follow-up, mid- to long-term clinical and radiographic outcomes were assessed. FCS was recorded.ResultsRegarding McKay’s clinical criteria, both groups exhibited similar results (p = 0.761). No significant differences were observed between the groups in both the center–edge–angle (p = 0.112) and the Severin score (p = 0.275). The AVN rate was 32% in the AOR group and 20% in the MOR group (p = 0.264). The FCS rate was 22% in the AOR group and 12% in the MOR group (p = 0.464).ConclusionsThis study showed similar clinical and radiological outcomes with AOR and MOR with no significant relation to AVN and FCS.Level of EvidenceLevel III.     

Examining the Short-Term Natural History of Developmental Dysplasia of the Hip in Infancy: A Systematic Review

BackgroundThis study was an update on the AAOS clinical practice guideline’s analysis of the natural history of developmental dysplasia of the hip (DDH). The objective was to delineate the natural history of clinical instability or radiologic abnormalities of the hip in infants by identifying the proportion of cases that resolved without treatment compared to cases that progressed and/or required treatment.MethodsWe performed a literature search of PUBMED to identify studies which evaluated the natural history of DDH. We used the same search strategy as that utilized in the previous AAOS guidelines, updated to include articles published between September 2013 and May 2021. We assessed the quality of included articles using the Oxford Centre for Evidence-Based Medicine level of evidence and reported study demographics and outcomes using summary statistics.ResultsTwenty-four articles met our eligibility criteria. Most included studies were retrospective (14/24), investigated either the incidence of DDH (8/24) or assessed screening programs (7/24). The most prevalent study population followed were Graf 2A hips (7/24). Most studies were low quality with level of evidence 3 (13/24) or 4 (7/24). Sample sizes ranged from 9 to 3251. Twenty studies reported the number of cases resolved over the follow-up period with a mean rate of 84.3% (95% confidence interval 76.1, 92.6).ConclusionWe found most mild-to-moderate DDH can resolve without treatment in early infancy, especially in physiologically immature (Graf 2A) hips. More high-quality evidence is needed to properly assess the natural history of DDH as only one included study was a randomized trial.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43465-021-00510-6.     

Microfracture of Acetabular Rim After Segmental Labral Resection to Restore the Morphology and Function of Labrum: A Retrospective Study of More than 2 Years Follow‐up

ObjectiveTo report on the clinical outcome of patients undergoing combined arthroscopic treatment of labral resection and microfracture at the rim of acetabulum at a minimum 2‐year follow‐up.MethodsThe retrospective study included 38 patients undergoing hip arthroscopy for irreparable labral injury from 24 February 2014 to 26 February 2018. Thirteen patients were excluded owing to patient refusal of participation and concomitant diseases like synovial chondromatosis and dysplasia hip. The study group consisted of patients undergoing combined arthroscopic labral resection and microfracture at the rim of acetabulum (MICRO Group: 20 patients), arthroscopic labral resection alone (RESEC Group: five patients). Postoperative three‐dimensional (3D) double‐echo steady‐state (DESS) sequence with radial imaging at 3 Tesla were obtained and fluoroscopic image of the involved hip under distraction were used to observe the restoration of vacuum effect. Patient‐reported outcome scores (PROs) including the Harris Hip Score (HHS), Visual Analogue Score (VAS), Hip Outcome Score Activities of Daily Living Subscale (HOS‐ADL), Hip Outcome Score Sport‐Specific Subscale (HOS‐SSS) were collected and compared between two groups.ResultsAll patients were followed up for at least 6 months. The follow‐up time of RESEC group is longer than MICRO group (46.6 months vs 23.9 months, P < 0.05). The 3D DESS imaging demonstrated intermediate signal intensity at the relative area where the labrum resected followed by microfracture at the acetabular rim in MICRO group. Meanwhile, regrowth of labrum‐like tissue was not observed in MRI imaging of the RESEC group. Furthermore, vacuum effect was more apparent in MICRO group compared with RESEC group. All PROs in both groups showed a statistically significant improvement at follow‐up compared with preoperative levels. RESEC group: HHS (73.0 vs 93.8, P < 0.05); HOS‐ADL (51.5 vs 89.1, P < 0.05); HOS‐SSS (47.8 vs 88.3, P < 0.05); VAS (6.4 vs 2.0, P < 0.05). MICRO group: HHS (70.5 vs 91.5, P < 0.05); HOS‐ADL (52.4 vs 87.0, P < 0.05); HOS‐SSS (48.1 vs 86.5, P < 0.05); VAS (6.3 vs 1.6, P < 0.05). One patient of MICRO group had transient neurapraxias of the pudendal nerve that resolved completely by 3 months. There showed no statistically significant difference between groups regarding the preoperative and postoperative PROs.ConclusionCompared to labral resection, combined arthroscopic labral resection and microfracture at the rim of acetabulum is able to fulfill the labral defect area with the potential to restore the seal effect of labrum as an effective and safe option for irreparable segmental labral tears.     

Comparison of Trochanteric Slide and Subtrochanteric Shortening Osteotomy in the Treatment of Severe Hip Dysplasia: Mid-Term Clinical Outcomes of Cementless Total Hip Arthroplasty

BackgroundThe aim of this study is to compare clinical results of Crowe type III-IV developmental dysplasia of the hip (DDH) patients who underwent total hip arthroplasty with either trochanteric slide osteotomy (TSO) or subtrochanteric shortening osteotomy (SSO).MethodsThe patients who underwent cementless total hip arthroplasty with femoral shortening osteotomy due to Crowe type III/IV DDH between 2004 and 2014 and completed at least 5 years of follow-up were retrospectively analyzed. The patients were grouped according to the type of shortening osteotomy as either TSO or SSO. Preoperative and postoperative clinical evaluation included Harris Hip Score, Visual Analogue Scale pain, leg length discrepancy, and the presence of Trendelenburg sign. The clinical outcome measures and complication rates were compared in terms of osteotomy type.ResultsThe TSO group consisted of 34 patients (43 hips) and the SSO group consisted of 40 patients (51 hips). The SSO group (96.1%) had a slightly higher 5-year survival of the implant compared to TSO (93%) without statistical significance (P = .18). No significant difference was detected between the groups in terms of clinical outcomes. Complication rates did not significantly differ between the groups except for the lack of bony union which was significantly higher in TSO (P = .006) but this difference did not transform into clinical significance since 5 of 6 patients who did not have a bony union in the TSO group were symptom-free with a fibrous union.ConclusionTSO and SSO provide similar clinical outcomes at mid-term follow-up in the management of Crowe III-IV DDH by cementless total hip arthroplasty. Both techniques can be used safely depending on the surgeon’s preference.Level of EvidenceLevel III, Therapeutic, Case-control study.     

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

BackgroundThe 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.MethodsOne 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.ResultsThe 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%.ConclusionTransverse 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.     

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

ObjectiveThe 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.MethodsWe 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.ResultsThe 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.ConclusionImproved 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.     

Clinical Outcome of Surgical Hip Dislocation Combined with Impacting Bone Grafts and Implanting Iliac Bone Flaps in the Treatment of Osteonecrosis of the Femoral Head: A Mid‐term Retrospective Study

ObjectiveTo report the medium‐term outcomes of surgical hip dislocation (SHD) combined with impacting bone grafts and implanting iliac bone flaps in the treatment of osteonecrosis of the femoral head (ONFH) and to define the indications for this treatment.MethodsThis was a single‐center retrospective study. In total, 64 patients (70 hips) with ONFH treated from January 2014 to December 2017 were included in this study. There were 51 males and 13 females aged 18–55 years with an average age of 32 years. All patients underwent surgery for SHD combined with impacting bone grafts and implanting iliac bone flaps. Preoperative and postoperative clinical outcomes were assessed. The clinical outcome was assessed using the Harris hip score (HHS) and the conversion rate of total hip arthroplasty (THA). Univariate and multivariate logistic regression analyses were performed to identify risk factors affecting the clinical outcome. Kaplan–Meier (K‐M) analysis was applied to calculate the survival rate of the femoral head.ResultsAt the last follow‐up (60 ± 15.08 months), the HHS was excellent for 41 hips, good for 17 hips, fair for three hips, and poor for nine hips. All nine hips with poor HHS underwent THA, including five in the first 2 years following the index surgery and four between three and 5 years. The conversion rate of total hip arthroplasty was 12.86%. Univariate and multivariate logistic regression analyses showed that the duration of hip pain and JIC classification type were significantly associated with clinical outcomes. Elderly age and advanced ONFH stage tended to lead to worse surgical outcomes. The overall survival rate of JIC classification type C1 and duration of pain ≤6 months was 98.1% and 97.8% at 72 months, respectively, as estimated by the Kaplan–Meier method.ConclusionSurgical hip dislocation combined with impacting bone grafts and implanting iliac bone flaps in the treatment of ONFH had a good mid‐term clinical outcome, especially for patients with retention of the lateral column of the femoral head and hip pain less than 1 year.